Vitamin D deficiency and the risk of tuberculosis: a meta-analysis

The effects of meteorological factors and air pollutants on the incidence of tuberculosis in people living with HIV/AIDS in subtropical Guangxi, China

BACKGROUND

Previous studies have shown the association between tuberculosis (TB) and meteorological factors/air pollutants. However, little information is available for people living with HIV/AIDS (PLWHA), who are highly susceptible to TB.

METHOD

Data regarding TB cases in PLWHA from 2014 to2020 were collected from the HIV antiviral therapy cohort in Guangxi, China. Meteorological and air pollutants data for the same period were obtained from the China Meteorological Science Data Sharing Service Network and Department of Ecology and Environment of Guangxi. A distribution lag non-linear model (DLNM) was used to evaluate the effects of meteorological factors and air pollutant exposure on the risk of TB in PLWHA.

RESULTS

A total of 2087 new or re-active TB cases were collected, which had a significant seasonal and periodic distribution. Compared with the median values, the maximum cumulative relative risk (RR) for TB in PLWHA was 0.663 (95% confidence interval [CI]: 0.507-0.866, lag 4 weeks) for a 5-unit increase in temperature, and 1.478 (95% CI: 1.116-1.957, lag 4 weeks) for a 2-unit increase in precipitation. However, neither wind speed nor PM10 had a significant cumulative lag effect. Extreme analysis demonstrated that the hot effect (RR = 0.638, 95%CI: 0.425-0.958, lag 4 weeks), the rainy effect (RR = 0.285, 95%CI: 0.135-0.599, lag 4 weeks), and the rainless effect (RR = 0.552, 95%CI: 0.322-0.947, lag 4 weeks) reduced the risk of TB. Furthermore, in the CD4(+) T cells < 200 cells/µL subgroup, temperature, precipitation, and PM10 had a significant hysteretic effect on TB incidence, while temperature and precipitation had a significant cumulative lag effect. However, these effects were not observed in the CD4(+) T cells ≥ 200 cells/µL subgroup.

CONCLUSION

For PLWHA in subtropical Guangxi, temperature and precipitation had a significant cumulative effect on TB incidence among PLWHA, while air pollutants had little effect. Moreover, the influence of meteorological factors on the incidence of TB also depends on the immune status of PLWHA.

Revisiting the association between vitamin D deficiency and active tuberculosis: A prospective case-control study in Taiwan

BACKGROUND

To revisit the association between vitamin D deficiency (VDD, defined as serum 25(OH)D < 20 ng/ml) and incident active tuberculosis (TB), after two potentially underpowered randomized trials showed statistically non-significant 13%-22% decrease in TB incidence in vitamin D supplementation groups.

METHODS

We prospectively conducted an age/sex-matched case-control study that accounting for body-mass index (BMI), smoking, and other confounding factors to examine the association between VDD and active TB among non-HIV people in Taiwan (latitude 24°N), a high-income society which continues to have moderate TB burden.

RESULTS

We enrolled 62 people with incident active TB and 248 people in control group. The TB case patients had a significantly higher proportion of VDD compared to the control group (51.6% vs 29.8%, p = 0.001). The 25(OH)D level was also significantly lower in TB patients compared to control group (21.25 ± 8.93 ng/ml vs 24.45 ± 8.36 ng/ml, p = 0.008). In multivariable analysis, VDD (adjusted odds ratio [aOR]: 3.03, p = 0.002), lower BMI (aOR: 0.81, p < 0.001), liver cirrhosis (aOR: 8.99, p = 0.042), and smoking (aOR: 4.52, p = 0.001) were independent risk factors for incident active TB.

CONCLUSIONS

VDD is an independent risk factor for incident active TB. Future randomized trials examining the effect of vitamin D supplementation on TB incidence should focus on people with a low BMI or other risk factors to maximize the statistical power.

Association of vitamin D with HIV infected individuals, TB infected individuals, and HIV-TB co-infected individuals: a systematic review and meta-analysis

Background

Vitamin D deficiency (VDD) is a worldwide disease. VDD is also associated with an increased risk of HIV-related comorbidities and mortality, and patients have a tendency to develop active tuberculosis compared to those with latent tuberculosis infection. Vitamin D supplementation may modulate HIV replication, improve TB inflammation and reduce progression of HIV-TB co-infection.

Methods

We meta-analyzed individual participant data from cohort studies, cross-sectional study, and RCTs of vitamin D in HIV group, TB group, and HIV-TB group. The primary outcomes were differences in vitamin D level and VDD prevalence between three groups, the secondary outcomes were CD4 count, HIV viral load, time to sputum smear conversion, time to culture conversion, relapse, morality, and TB score.

Results

For vitamin D levels, the overall mean difference (MD) between HIV group and TB group was -0.21 (95% CI, -20.80-20.38; p = 0.9, I2 = 84%), HIV group and HIV-TB group was 0.87 (95% CI, -11.45-13.20; p = 0.89, I2 = 87%), and TB group and HIV-TB group was 1.17 (95% CI, -5.21-7.55; p = 0.72, I2 = 85%). For vitamin D deficiency prevalence, the overall odds ratio (OR) for HIV group versus TB group was 1.23 (95% CI, 0.46-3.31; p = 0.68; I2 = 70%), HIV group versus HIV-TB group was 1.53 (95% CI, 1.03-2.29; p = 0.04; I2 = 0%), and TB group versus HIV-TB group was 0.85 (95% CI, 0.61-1.20; p = 0.36; I2 = 22%). In HIV-TB group, the overall OR for vitamin D group versus placebo group was 0.78 (95% CI, 0.34-1.67; p = 0.52; I2 = 60%).

Conclusion

Our findings indicated that there were no variations in vitamin D levels between three groups. The prevalence of vitamin D deficiency was higher in the HIV-TB group than in the HIV group. Additionally, the administration of vitamin D supplements did not have obvious impact on CD4 count and viral load. Likewise, vitamin D had no effect on time to sputum smear conversion, time to culture conversion, relapse, 12-month morality, and TB score.

Mechanistic Insight into the role of Vitamin D and Zinc in Modulating Immunity Against COVID-19: A View from an Immunological Standpoint

The pathophysiology of coronavirus disease-19 (COVID-19) is characterized by worsened inflammation because of weakened immunity, causing the infiltration of immune cells, followed by necrosis. Consequently, these pathophysiological changes may lead to a life-threatening decline in perfusion due to hyperplasia of the lungs, instigating severe pneumonia, and causing fatalities. Additionally, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can cause mortality due to viral septic shock, resulting from unrestrained and backfiring immune reactions to the pathogen. Sepsis can cause premature organ failure in COVID-19 patients, as well. Notably, vitamin D and its derivatives and minerals, such as zinc and magnesium, have been reported to improve the immune system against respiratory illnesses. This comprehensive review aims to provide updated mechanistic details of vitamin D and zinc as immunomodulators. Additionally, this review also focuses on their role in respiratory illnesses, while specifically delineating the plausibility of employing them as a preventive and therapeutic agent against current and future pandemics from an immunological perspective. Furthermore, this comprehensive review will attract the attention of health professionals, nutritionists, pharmaceuticals, and scientific communities, as it encourages the use of such micronutrients for therapeutic purposes, as well as promoting their health benefits for a healthy lifestyle and wellbeing.

Association between vitamin D and knee osteoarthritis in Indian population: A systematic review and meta-analysis

Background

Vitamin D deficiency (VDD) has been implicated in knee osteoarthritis (KOA) development and progression. Prevalence of hypovitaminosis D and osteoporosis in KOA is widely reported in Indian population. However, there is no attempt to critically evaluate the outcome of these studies. We aimed a systematic review of these studies.

Methods

Pubmed, Google Scholar and Web of Science last updated March 2023, were searched. We reviewed eligible studies on the association between KOA and vitamin D levels in Indian and Asian population for comparison. The mean difference (MD) of vitamin D levels and odds ratio (OR) of vitamin D status were calculated. Data were interpreted by RevMan 5.4 software. The risk of bias was assessed using the Cochrane Risk of Bias tool.

Results

A total of 15 studies that involved 1503 KOA cases and 1609 controls were included. There was significantly reduced level of vitamin D in KOA (MD -8.68 ng/mL, 95%CI -12.21 to -5.15; P = <0.00001, I2 = 82 %) in Indian population. Similarly, in other Asian population significantly reduced vitamin D levels in KOA (MD 18.36 ng/mL, 95%CI -34.72 to -2.00; P = <0.00001, I2 = 100 %) was observed in KOA. VDD was found to be positively correlated with an increased risk of KOA.

Conclusion

Early diagnosis and management of VDD may provide the opportunity to delay the ongoing degenerative process of KOA and this study indicates the importance of screening VDD even in sunlight rich regions.

The association of vitamin D and digestive system cancers: a comprehensive Mendelian randomization study

BACKGROUND

Hitherto, the association of vitamin D intake and digestive system cancers occurrence still causes disputation among the researchers. This study aimed to investigate the genetic relation between vitamin D ingestion and digestive system cancers (which are esophageal, gastric, hepatic, pancreatic, and colorectal cancers) by a two-sample Mendelian randomization (MR) analysis, using datasets derived from IEU OpenGWAS database.

METHODS

This study is based on a genome-wide association study (GWAS) for vitamin D and digestive system cancers, with a sample amount ranging from 218,792 to 496,946 European ancestry individuals. The study first investigated the causal relationship between vitamin D and each digestive system cancers using inverse-variance weighting (IVW), weighted medians, and MR-Egger regression and then used meta-analysis to summarize the IVW results for the different cancers. We also performed additional sensitivity tests to assess the validity of the results.

RESULTS

In this study, we screened out 117 SNPs as potential instrumental variables for 25(OH)D and identified 101 fixed SNPs as instrumental variables for digestive system cancers. The results of the IVW failed to reveal any causal relationship between the genetically predisposed vitamin D level and the risk of digestive system cancers (esophageal cancer p = 0.400, OR = 1.397, 95% CI 0.642-3.040; gastric cancer p = 0.796, OR = 0.939, 95% CI 0.585-1.510; hepatic cancer p = 0.347, OR = 1.445, 95% CI 0.671-3.109; pancreatic cancer p = 0.905, OR = 0.969, 95% CI 0.581-1.618; colorectal cancer p = 0.127, OR = 0.0.841, 95% CI 0.673-1.051). The pooled ORs (odds ratio) are 0.918 (95% CI 0.770-1.097, p = 0.348).

CONCLUSION

There is no causal relationship between vitamin D and the occurrence of digestive system cancers. The risk of digestive system cancers cannot be alleviated by merely increasing vitamin D intake.

In Vivo Regulation of Signal Transduction Pathways by Vitamin D Stabilizes Homeostasis of Human Immune Cells and Counteracts Molecular Stress

Vitamin D3 is a pre-hormone that regulates hundreds of target genes and dozens of physiological functions, including calcium homeostasis and the activity of the immune system, via its metabolite 1,25-dihydroxyvitamin D3, which is a high-affinity ligand for the transcription factor vitamin D receptor. In this study, we took advantage of data from the VitDHiD vitamin D3 intervention trial (25 healthy individuals) indicating that 442 protein-coding genes were significantly (false discovery rate < 0.05) up- or downregulated in peripheral blood mononuclear cells one day after taking a vitamin D3 bolus. Since more than half of the encoded proteins had "signaling" assigned as a primary biological function, we evaluated their involvement in signal transduction cascades included in the KEGG (Kyoto Encyclopedia of Genes and Genomes) database and found 88 of the vitamin D targets contributing to 16 different pathways. Eight of the pathways show an approximately even contribution of up- and downregulated genes, suggesting that the actions of vitamin D stabilize homeostasis of the physiological processes driven by the respective signaling cascades. Interestingly, vitamin D target genes involved in the signaling pathways of hypoxia-inducible factor 1 (HIF1), tumor necrosis factor (TNF), mitogen-activated protein kinases (MAPKs) and nuclear factor κB (NFκB) are primarily downregulated. This supports the observation that the physiological role of vitamin D in healthy individuals is to tone down certain processes rather than activate them. In conclusion, under in vivo conditions, vitamin D either alleviates the homeostasis of immune cells in healthy individuals or counteracts molecular responses to oxygen deprivation (HIF1), microbe infection (TNF), growth stimulation (MAPKs) and inflammation (NFκB).

Intervention Approaches in Studying the Response to Vitamin D3 Supplementation

Vitamin D intervention studies are designed to evaluate the impact of the micronutrient vitamin D3 on health and disease. The appropriate design of studies is essential for their quality, successful execution, and interpretation. Randomized controlled trials (RCTs) are considered the "gold standard" for intervention studies. However, the most recent large-scale (up to 25,000 participants), long-term RCTs involving vitamin D3 did not provide any statistically significant primary results. This may be because they are designed similarly to RCTs of a therapeutic drug but not of a nutritional compound and that only a limited set of parameters per individual were determined. We propose an alternative concept using the segregation of study participants into different groups of responsiveness to vitamin D3 supplementation and in parallel measuring a larger set of genome-wide parameters over multiple time points. This is in accordance with recently developed mechanistic modeling approaches that do not require a large number of study participants, as in the case of statistical modeling of the results of a RCT. Our experience is based on the vitamin D intervention trials VitDmet, VitDbol, and VitDHiD, which allowed us to distinguish the study participants into high, mid, and low vitamin D responders. In particular, investigating the vulnerable group of low vitamin D responders will provide future studies with more conclusive results both on the clinical and molecular benefits of vitamin D3 supplementation. In conclusion, our approach suggests a paradigm shift towards detailed investigations of transcriptome and epigenome-wide parameters of a limited set of individuals, who, due to a longitudinal design, can act as their own controls.

Impact of micro- and macronutrient status on the incidence of tuberculosis: An examination of an African cohort initiating antiretroviral therapy

Macronutrient and micronutrient deficiencies are associated with tuberculosis (TB) incidence. However, evidence is limited on the impact of micronutrient (vitamins and minerals) supplementation among underweight individuals. We conducted a secondary data analysis of a randomised controlled trial of lipid nutritional supplements with and without high-dose vitamin and mineral supplementation (LNS-VM vs LNS) for underweight (Body Mass Index [BMI] <18.5 kg/m2) adults with human immunodeficiency virus (HIV) initiating antiretroviral therapy (ART) in Tanzania and Zambia (2011-2013). Incident TB disease diagnoses were extracted from trial records. We used multivariable Cox regression to estimate hazard ratios (HR) for the impact of receiving LNS-VM on TB incidence, and the dose-response relationship between baseline BMI and TB incidence. Overall, 263 (17%) of 1506 participants developed TB disease. After adjusting for age, sex, CD4 count, haemoglobin, and C-reactive protein, receiving LNS-VM was not associated with TB incidence (aHR [95%CI] = 0.93 [0.72-1.20]; p = 0.57) compared to LNS alone. There was strong evidence for an association between lower BMI and incident TB (aHR [95%CI]: 16-16.9kg/m2 = 1.15 [0.82-1.62] and <16kg/m2 = 1.70 [1.26-2.30] compared to 17-18.5kg/m2; linear trend p<0.01). There was strong evidence that the rate of developing TB was lower after initiating ART (p<0.01). In conclusion, the addition of micronutrient supplementation to LNS was not associated with lower TB incidence in this underweight ART-naive population.

Long-term in vivo vitamin D3 supplementation modulates bovine IL-1 and chemokine responses

Vitamin D deficiency at birth, followed by prolonged insufficiency in early life may predispose bovine calves to infection and disease. However, the effects of vitamin D levels on innate immunity are unclear due to the lack of long-term supplementation trials in vivo and reliable approaches for reproducibly assessing immune function. Here, a standardized whole blood immunophenotyping assay was used to compare innate immune responses to infection relevant ligands (LPS, Pam3CSK4 and R848) between Holstein-Friesian calves supplemented with vitamin D (n = 12) from birth until 7 months of age and control calves (n = 10) raised on an industry standard diet. Transcriptomic analysis in unstimulated whole blood cells revealed increased expression of type I interferons and chemokines in vitamin D supplemented calves, while IL-1 and inflammasome gene expression was decreased. In response to stimulation with the bacterial ligand LPS, supplemented calves had significantly increased expression of CASP1, CX3CR1, CAT, whereas STAT1 was decreased. Stimulation with the bacterial ligand Pam3CSK4 revealed increased expression of IL1A, IL1B and CAT genes; and decreased C5AR1 expression. In response to the viral ligand R848, STAT1 and S100A8 expression was significantly decreased. An increased IL-1 and inflammasome gene expression signature in vitamin D supplemented calves in response to LPS and Pam3CSK4 was also found, with ELISA confirming increased IL-1β protein production. In contrast, a decreased chemokine gene expression signature was found in response to R848 in supplemented animals, with decreased IL-8 protein expression exhibited in response to all PAMPs also found. These results demonstrated expression of several cytokine, chemokine and inflammasome genes were impacted by vitamin D supplementation in the first 7 months of life, with IL-8 expression particularly responsive to vitamin D. Overall, vitamin D supplementation induced differential innate immune responses of blood immune cells that could have important implications for disease susceptibility in cattle.

Serum Vitamin D Levels in Pediatric Tuberculosis Patients in a Tertiary Care Center in India: A Case-Control Study

Background Mycobacterium is certainly one individual organism contributing to the most deaths of children among the world's lower- and medium-income nations. According to earlier studies, vitamin D insufficiency is one of the risk factors. We undertook this study since very few case-control studies are present. This study aimed to evaluate the role of vitamin D in tuberculosis (TB). Methods This case-control study was carried out in a tertiary care center at Niloufer Hospital over a period of one year and five months. The sample size was 140. SPSS (Statistical Package for the Social Sciences) Version 19 (IBM Corp., Armonk, NY) was used for statistical analysis. Two-tailed p-values and odds ratios were obtained. The chi-square test was applied to differentiate between two categorical variables. For means, the Student t-test was applied. We usually take baseline investigations before starting ATT (anti-TB treatment) with the blood sample we tested for vitamin D levels. Results With p-values of 0.767 and 0.866, the age and sex distributions in the cases and controls were comparable. Rural and urban area distribution and malnutrition distribution were not similar in both groups, with a p-value of 0.001. The mean vitamin D level in cases was 10.4, while controls it was 22.8, and this difference is statistically significant (p = 0.001). Conclusion Vitamin D deficiency is more common in children with TB than in normal children. In addition, a severe form of vitamin D deficiency (less than 10 ng/mL) was higher among children with TB. Clinicians should be aware of associated malnutrition and low socioeconomic status as risk factors for severe vitamin D deficiencies among them.

Association of circulating serum free bioavailable and total vitamin D with cathelicidin levels among active TB patients and household contacts

The free hormone hypothesis postulates that the estimation of free circulating 25 (OH)D may be a better marker of vitamin D status and is of clinical importance compared to total vitamin D fraction. The unbound fraction is involved in biological activities since it is able to penetrate into the cell. Studies have shown that cathelicidin/LL-37 inhibits the growth of Mycobacterium tuberculosis in a vitamin D-dependent manner and therefore adequate vitamin D is required for its expression. The study aimed to determine the association between serum bioavailable and total vitamin D with LL-37 levels in ATB patients, LTBI, and individuals with no TB infection. This was a cross-sectional study in which bioavailable vitamin D and LL-37 levels were measured using competitive ELISA kits and total vitamin D was measured using electrochemilumiscence and consequently determined their association. The mean (SD) bioavailable vitamin D levels of the study participants were 3.8 ng/mL (2.6) and the median (IQR) of LL-37 levels were 320 ng/mL (160, 550 ng/mL). The mean (SD) of total vitamin D levels was 19.0 ng/mL (8.3) ng/mL. Similar weak correlations were observed between the bioavailable and total vitamin D with LL-37 levels, therefore, deviating from our hypothesis.

Long term dietary vitamin D3 supplementation impacts both microbicidal and inflammatory responses to ex-vivo Mycobacterium bovis BCG challenge in dairy calves

Vitamin D deficiency (VDD) is associated with enhanced susceptibility to multiple respiratory diseases in humans, including tuberculosis. However, the consequences of VDD for disease susceptibility in calves are unknown. Previously we developed a model to drive divergent circulating 25OHD concentrations in cattle, where animals were supplemented with vitamin D₃ (vit D₃) from birth to 7 months of age. Calves in the control group (Ctl) received a diet containing a standard vit D₃ concentration, whereas the vit D group (VitD) received a diet with the highest vit D₃ concentration allowed under EU guidelines. Here, we assessed the microbicidal activity and immunoregulatory effect of divergent 25OHD circulating levels to Mycobacterium bovis BCG challenge ex-vivo. Blood samples from Ctl and VitD calves were taken at 1-, 3- and 7-months of age. 25OHD concentrations were significantly different at 7 months (but not at 1 or 3 months) with animals from the VitD group having higher serum levels. Differences in microbicidal activity followed the same pattern, with no significant differences observed at 1 and 3 months, but at 7 months a significant increase in the percentage of bacteria killed was detected. Furthermore, analysis of the reactive oxygen species (ROS) and nitric oxide (NO) in serum showed a higher production of ROS and NO in VitD-supplemented calves. In contrast, serum concentrations of IL-1β and IL-8 were significantly lower. A similar anti-inflammatory profile was observed after gene expression analysis, with a significant downregulation of a cluster of genes including IL1B, IL1R1, CXCL1, CXCL2, CXCL5, MMP9 and COX2 and an upregulation of CXCR1, CX3CR1 and NCF1, in VitD calves after BCG challenge relative to Ctl animals. Collectively, these results suggest that dietary vit D₃ boosts antimicrobial and innate immune responses and thereby could improve host anti-mycobacterial immunity.

Vitamin D: A master example of nutrigenomics

Nutrigenomics attempts to characterize and integrate the relation between dietary molecules and gene expression on a genome-wide level. One of the biologically active nutritional compounds is vitamin D₃, which activates via its metabolite 1α,25-dihydroxyvitamin D₃ (1,25(OH)₂D₃) the nuclear receptor VDR (vitamin D receptor). Vitamin D₃ can be synthesized endogenously in our skin, but since we spend long times indoors and often live at higher latitudes where for many winter months UV-B radiation is too low, it became a true vitamin. The ligand-inducible transcription factor VDR is expressed in the majority of human tissues and cell types, where it modulates the epigenome at thousands of genomic sites. In a tissue-specific fashion this results in the up- and downregulation of primary vitamin D target genes, some of which are involved in attenuating oxidative stress. Vitamin D affects a wide range of physiological functions including the control of metabolism, bone formation and immunity. In this review, we will discuss how the epigenome- and transcriptome-wide effects of 1,25(OH)₂D₃ and its receptor VDR serve as a master example in nutrigenomics. In this context, we will outline the basis of a mechanistic understanding for personalized nutrition with vitamin D₃.

Vitamin D, Menopausal Health and COVID-19: Critical Appraisal of Current Data

Inconsistency exists across studies conducted in postmenopausal women regarding the effect of vitamin D deficiency (VDD) and supplementation on several aspects of menopausal health, such as fractures, vasomotor symptomatology, cardiovascular disease (CVD), cancer and infections, including coronavirus disease 2019 (COVID-19). The aim of this review is to critically summarize the evidence provided by observational studies and randomized controlled trials (RCTs) of vitamin D supplementation in postmenopausal women with VDD. Observational studies have found that VDD is associated with an increased risk of falls and fractures after the menopause. VDD also has a negative effect on menopausal symptomatology. VDD, especially its severe form, is associated with an increased risk of CVD risk factors and CVD events. VDD is associated with increased risk and mortality from several cancer types and risk of infections. The evidence from RCTs regarding the effect of vitamin D supplementation on falls, fractures, menopausal symptoms, cardiovascular disease, cancer and infections is not robust. Thus, skeletal health may benefit only when vitamin D is co-administered with calcium, especially in those ≥70 years old and with severe VDD. There is no evidence of a favorable effect on menopausal symptoms or risk of CVD or cancer, except for a modest reduction in cancer-related mortality. Inconsistency still exists regarding its effect on infection risk, disease severity and mortality due to COVID-19.

Vitamin D3 alters macrophage phenotype and endosomal trafficking markers in dairy cattle naturally infected with Mycobacterium avium subsp. paratuberculosis

Macrophages are important host defense cells in ruminant paratuberculosis (Johne’s Disease; JD), a chronic enteritis caused by Mycobacterium avium subsp. paratuberculosis (MAP). Classical macrophage functions of pathogen trafficking, degradation, and antigen presentation are interrupted in mycobacterial infection. Immunologic stimulation by 25-hydroxyvitamin D₃ (25(OH)D₃) and 1,25-dihydroxyvitamin D₃ (1,25(OH)₂D₃) enhances bovine macrophage function. The present study aimed to investigate the role of vitamin D₃ on macrophage phenotype and endosomal trafficking of MAP in monocyte-derived macrophages (MDMs) cultured from JD-, JD+ subclinical, and JD+ clinically infected cattle. MDMs were pre-treated 100 ng/ml 25(OH)D₃ or 4 ng/ml 1,25(OH)₂D₃ and incubated 24 hrs with MAP at 10:1 multiplicity of infection (MOI). In vitro MAP infection upregulated pro-inflammatory (M1) CD80 and downregulated resolution/repair (M2) CD163. Vitamin D₃ generally decreased CD80 and increased CD163 expression. Furthermore, early endosomal marker Rab5 was upregulated 140× across all stages of paratuberculosis infection following in vitro MAP infection; however, Rab5 was reduced in MAP-activated MDMs from JD+ subclinical and JD+ clinical cows compared to healthy controls. Rab7 expression decreased in control and clinical cows following MDM infection with MAP. Both forms of vitamin D₃ reduced Rab5 expression in infected MDMs from JD- control cows, while 1,25(OH)₂D₃ decreased Rab7 expression in JD- and JD+ subclinical animals regardless of MAP infection in vitro. Vitamin D₃ promoted phagocytosis in MDMs from JD- and JD+ clinical cows treated with either vitamin D₃ analog. Results from this study show exogenous vitamin D₃ influences macrophage M1/M2 polarization and Rab GTPase expression within MDM culture.

The Problem of Vitamin D Scarcity: Cultural and Genetic Solutions by Indigenous Arctic and Tropical Peoples

Vitamin D metabolism differs among human populations because our species has adapted to different natural and cultural environments. Two environments are particularly difficult for the production of vitamin D by the skin: the Arctic, where the skin receives little solar UVB over the year; and the Tropics, where the skin is highly melanized and blocks UVB. In both cases, natural selection has favored the survival of those individuals who use vitamin D more efficiently or have some kind of workaround that ensures sufficient uptake of calcium and other essential minerals from food passing through the intestines. Vitamin D scarcity has either cultural or genetic solutions. Cultural solutions include consumption of meat in a raw or boiled state and extended breastfeeding of children. Genetic solutions include higher uptake of calcium from the intestines, higher rate of conversion of vitamin D to its most active form, stronger binding of vitamin D to carrier proteins in the bloodstream, and greater use of alternative metabolic pathways for calcium uptake. Because their bodies use vitamin D more sparingly, indigenous Arctic and Tropical peoples can be misdiagnosed with vitamin D deficiency and wrongly prescribed dietary supplements that may push their vitamin D level over the threshold of toxicity.

High prevalence of vitamin D insufficiency among South Asian pregnant women: a systematic review and meta-analysis

Insufficiency of vitamin D, during pregnancy, is a common cause of various pregnancy-related complications. Despite such insufficiency being frequently reported among South Asian pregnant women, the absence of systematic review and meta-analysis renders the true extent of this problem being poorly characterised. In this systematic review, three main databases (PubMed, Scopus and Google Scholar) were searched for original studies. We included original studies published between 1January 2001 to 31 December 2019, conducted on pregnant women who lived in South Asian countries and reported the prevalence of vitamin D insufficiency among the study participants. Twenty studies with a total of 7804 participants from four South Asian countries finally met our selection criteria. Overall pooled prevalence of insufficiency was 65 % (95 % CI: 51 %, 78 %) with a significant heterogeneity (I² = 99·37 %; P = 0·00). The average level of vitamin D ranged from 9 ng/ml to 24·86 ng/ml with a weighted mean of 16·37 ng/ml (weighted standard deviation 7·13 ng/ml). The highest prevalence of insufficiency was found in Pakistan (76 %) followed by India (67 %), Bangladesh (64 %) and Nepal (14 %). Results obtained in this study suggest that vitamin D insufficiency is highly prevalent among South Asian pregnant women. Being the first systematic review in this region, findings from this study will help the future studies and strengthen the evidence for policymakers to develop effective mitigation strategies.

The Crosstalk between Vitamin D and Pediatric Digestive Disorders

Vitamin D is a cyclopentane polyhydrophenanthrene compound involved mainly in bone health and calcium metabolism but also autophagy, modulation of the gut microbiota, cell proliferation, immune functions and intestinal barrier integrity. The sources of vitamin D include sunlight, diet and vitamin D supplements. Vitamin D3, the most effective vitamin D isoform is produced in the human epidermis as a result of sunlight exposure. Vitamin D undergoes two hydroxylation reactions in the liver and kidney to reach its active form, 1,25-dihydroxyvitamin D. Recent studies highlighted a complex spectrum of roles regarding the wellbeing of the gastrointestinal tract. Based on its antimicrobial effect, it was recently indicated that vitamin D supplementation in addition to standard eradication therapy might enhance H. pylori eradication rates. Moreover, it was suggested that low levels of vitamin D might also be involved in the acquisition of H. pylori infection. In terms of celiac disease, the negative effects of vitamin D deficiency might begin even during intrauterine life in the setting of maternal deficiency. Moreover, vitamin D is strongly related to the integrity of the gut barrier, which represents the core of the pathophysiology of celiac disease onset, in addition to being correlated with the histological findings of disease severity. The relationship between vitamin D and cystic fibrosis is supported by the involvement of this micronutrient in preserving lung function by clearing airway inflammation and preventing pathogen airway colonization. Moreover, this micronutrient might exert anticatabolic effects in CF patients. Inflammatory bowel disease patients also experience major benefits if they have a sufficient level of circulating vitamin D, proving its involvement in both induction and remission in these patients. The findings regarding the relationship between vitamin D, food allergies, diarrhea and constipation remain controversial, but vitamin D levels should be monitored in these patients in order to avoid hypo- and hypervitaminosis. Further studies are required to fill the remaining gaps in term of the complex impact of vitamin D on gastrointestinal homeostasis.

Case-control study of vitamin D status and adult multidrug-resistant pulmonary TB

BACKGROUND: India has the highest prevalence of multidrug-resistant TB (MDR-TB) globally. Vitamin D deficiency is potentially an important risk factor for MDR-TB.METHODS: We conducted a case-control study of 90 newly diagnosed adult MDR-TB cases, 180 household controls and 82 non-household controls in Mumbai, India. Serum 25-hydroxyvitamin D (25(OH)D), anthropometry, clinical status and history, dietary data and sociodemographic data were collected from each participant. Interferon-gamma release assay (IGRA) was also performed in controls to assess latent TB. Multivariable regression was performed to estimate associations between 25(OH)D vs. case status and IGRA positivity.RESULTS: Mean participant age was 33.8 ± 12.0 years; 72.8% had 25(OH)D <20 ng/ml. Mean 25(OH)D was significantly (P < 0.05) lower in cases (12.5 ± 7.9) than both household (17.5 ± 11.2) and non-household controls (16.4 ± 9.1). In multivariable models, 25(OH)D concentration was inversely associated with MDR-TB case status among cases and household controls (OR 0.95 per 1 ng/ml, 95% CI 0.92-0.99; P = 0.015), and among cases and non-household controls (OR 0.94 per 1 ng/ml, 95% CI 0.89-1.00; P = 0.033); 53.6% of controls were IGRA-positive. 25(OH)D status was not associated with IGRA positivity.CONCLUSION: Vitamin D status was independently associated with MDR-TB case status. Research should evaluate the effectiveness of vitamin D supplementation in prevention and adjunctive treatment of MDR-TB.

Vitamin D in the Context of Evolution

For at least 1.2 billion years, eukaryotes have been able to synthesize sterols and, therefore, can produce vitamin D when exposed to UV-B. Vitamin D endocrinology was established some 550 million years ago in animals, when the high-affinity nuclear receptor VDR (vitamin D receptor), transport proteins and enzymes for vitamin D metabolism evolved. This enabled vitamin D to regulate, via its target genes, physiological process, the first of which were detoxification and energy metabolism. In this way, vitamin D was enabled to modulate the energy-consuming processes of the innate immune system in its fight against microbes. In the evolving adaptive immune system, vitamin D started to act as a negative regulator of growth, which prevents overboarding reactions of T cells in the context of autoimmune diseases. When, some 400 million years ago, species left the ocean and were exposed to gravitation, vitamin D endocrinology took over the additional role as a major regulator of calcium homeostasis, being important for a stable skeleton. Homo sapiens evolved approximately 300,000 years ago in East Africa and had adapted vitamin D endocrinology to the intensive exposure of the equatorial sun. However, when some 75,000 years ago, when anatomically modern humans started to populate all continents, they also reached regions with seasonally low or no UV-B, i.e., and under these conditions vitamin D became a vitamin.

Gene-Regulatory Potential of 25-Hydroxyvitamin D3 and D2

Human peripheral blood mononuclear cells (PBMCs) represent a highly responsive primary tissue that is composed of innate and adaptive immune cells. In this study, we compared modulation of the transcriptome of PBMCs by the vitamin D metabolites 25-hydroxyvitamin D₃ (25(OH)D₃), 25(OH)D₂ and 1α,25-dihydroxyvitamin D₃ (1,25(OH)₂D₃). Saturating concentrations of 1,25(OH)₂D₃, 25(OH)D₃ and 25(OH)D₂ resulted after 24 h stimulation in a comparable number and identity of target genes, but below 250 nM 25(OH)D₃ and 25(OH)D₂ were largely insufficient to affect the transcriptome. The average EC₅₀ values of 206 common target genes were 322 nM for 25(OH)D₃ and 295 nM for 25(OH)D₂ being some 600-fold higher than 0.48 nM for 1,25(OH)₂D₃. The type of target gene, such as primary/secondary, direct/indirect or up-/down-regulated, had no significant effect on vitamin D metabolite sensitivity, but individual genes could be classified into high, mid and lower responders. Since the 1α-hydroxylase CYP27B1 is very low expressed in PBMCs and early (4 and 8 h) transcriptome responses to 25(OH)D₃ and 25(OH)D₂ were as prominent as to 1,25(OH)₂D₃, both vitamin D metabolites may directly control gene expression. In conclusion, at supra-physiological concentrations 25(OH)D₃ and 25(OH)D₂ are equally potent in modulating the transcriptome of PBMCs possibly by directly activating the vitamin D receptor.

No smoke without fire: the impact of cigarette smoking on the immune control of tuberculosis

Cigarette smoke (CS) exposure is a key risk factor for both active and latent tuberculosis (TB). It is associated with delayed diagnosis, more severe disease progression, unfavourable treatment outcomes and relapse after treatment. Critically, CS exposure is common in heavily populated areas with a high burden of TB, such as China, India and the Russian Federation. It is therefore prudent to evaluate interventions for TB while taking into account the immunological impacts of CS exposure. This review is a mechanistic examination of how CS exposure impairs innate barrier defences, as well as alveolar macrophage, neutrophil, dendritic cell and T-cell functions, in the context of TB infection and disease.

Vitamin D receptor gene polymorphism and vitamin D supplementation on clinical/ treatment outcome in tuberculosis: current and future perspectives

INTRODUCTION

Tuberculosis (TB) is a transnational public health concern, which requires more precise treatment strategies than the existing approaches. Vitamin D modulates the inflammatory and immune response to the disease. Robust evidence shows that vitamin D deficiency and its receptor gene polymorphism influence the susceptibility to TB and the outcome of the anti-tubercular treatment (ATT). However, in the different populations, these findings were inconsistent and even contradictory.

AREAS COVERED

The current review focuses on the association between vitamin D receptor (VDR) gene polymorphism with the risk of development of TB disease and response to the ATT. Additionally, it reviews various systematic reviews and meta-analyses on the impact of vitamin D supplements on both clinical and treatment outcomes in TB patients.

EXPERT OPINION

Although the majority of the findings rule out the benefits of the supplementation, sufficient evidence is available to warrant larger epidemiological research that should be aimed to generate possible interaction among the VDR polymorphism, vitamin D status, and the outcome in TB. We conclude that establishing such an association in different ethnic populations will help design nutrigenomics- or pharmacogenomics-based vitamin D supplementation to develop a personalized medicine approach to flatten the curve of TB disease.

Associating the blood vitamin A, C, D and E status with tuberculosis: a systematic review and meta-analysis of observational studies

Vitamins may play an important role in preventing tuberculosis. The purpose of this work is to associate the vitamin A, C, D and E status with tuberculosis through a systematic review and meta-analysis of observational studies. Web of Science, Pubmed and Scopus were searched from the earliest date of the database to May 2021. The standardized mean differences (SMDs) of blood vitamin concentrations and odds ratios (ORs) of vitamin deficiency between the tuberculosis patients and the control subjects were used as the main effect sizes. The effect sizes were pooled by a random-effects model using the Stata software (Version 11). The vitamin A concentration was significantly lower in the tuberculosis group than in the control group [SMD (95% CI): -0.96 (-1.31, -0.61), p < 0.01]. Only two case-control studies reported the vitamin C concentrations in the tuberculosis group versus the control group, and the difference was not significant. The blood vitamin D concentration was significantly lower in the tuberculosis group than in the control group [SMD (95% CI): -0.53 (-0.75, -0.32), p < 0.01]. Consistently, the number of people with vitamin D deficiency was significantly higher in the tuberculosis group [OR (95% CI): 2.29 (1.55, 3.37), p < 0.01]. The vitamin E concentration was significantly lower in the tuberculosis group than in the control group [SMD (95% CI): -0.34 (-0.61, -0.08), p = 0.01]. The current meta-analysis suggested a negative association between the vitamin A, D and E status and tuberculosis, and the association between the vitamin C status and tuberculosis was inconclusive due to the limited studies available.

Impact of Vitamin D in Prophylaxis and Treatment in Tuberculosis Patients

Vitamin D plays a crucial role in many infectious diseases, such as tuberculosis (TB), that remains one of the world’s top infectious killers with 1.5 million deaths from TB in 2021. Vitamin D suppresses the replication of Mycobacterium tuberculosis in vitro and showed a promising role in TB management as a result of its connection with oxidative balance. Our review encourages the possible in vivo benefit of a joint administration with other vitamins, such as vitamin A, which share a known antimycobacterial action with vitamin D. However, considering the low incidence of side effects even at high dosages and its low cost, it would be advisable to assess vitamin D level both in patients with active TB and high-risk groups and administer it, at least to reach sufficiency levels.

Hypovitaminosis D among newly diagnosed pulmonary TB patients and their household contacts in Uganda

An estimated one billion people globally live with hypovitaminosis D. Studies have indicated that vitamin D deficiency is a risk factor for active tuberculosis (TB) disease. The aim of this study was to determine the association between vitamin D deficiency and TB status among patients with active TB, latent TB infection (LTBI) and those without TB infection. In a cross-sectional study of active TB patients, LTBI, QuantiFERON GOLD testpositive and (QFN⁺TST⁺) household contact and controls QuantiFERON GOLD testnegative (QFN⁻TST⁻) samples vitamin D levels were compared. Vitamin D status was determined by measurement of total vitamin D levels with 56 samples of active TB patients, 17 with LTBI, and 22 without TB infection using electrochemiluminescence. The median interquartile range (IQR) age of the study participants was 28 (20–35) years, and the majority (63%) were females. The median (IQR) vitamin D levels were 18 ng/ml (14–24). All groups had vitamin D hypovitaminosis with significantly lower levels among active TB patients (17 ng/ml, 13, 2) than among LTBI individuals (23 ng/ml 16–29) and those without TB infection (22 ng/ml, 17–28).

High burden of hypovitaminosis D among the children and adolescents in South Asia: a systematic review and meta-analysis

Background

Vitamin D is vital for the growth and development of children. While deficiency and/or insufficiency of vitamin D among South Asian children are frequently reported in the literature, the lack of a meta-analysis has left its true extent poorly characterized. In this study, we aimed to conduct a systematic review and perform meta-analyses of the prevalence of hypovitaminosis D among the children of the South Asian countries.

Methods

Two major electronic search engines (PubMed and Scopus) and one database (Google scholar) were used; original studies, conducted among South Asian children and adolescents and published between 1 January 2001 and 31 December 2019. A random-effect meta-analysis was also performed to calculate the pooled prevalence of hypovitaminosis D followed by subgroup analyses for countries and age groups.

Results

After applying inclusion and exclusion criteria, a total of 41 studies with a total population size of 18,233 were finally selected. The overall prevalence of hypovitaminosis D was 61% [95% CI: 46% to 71%] with highly significant heterogeneity (I² = 99.72%; p < 0.0001). The average level of serum vitamin D ranged from 5 ng/mL to 34 ng/mL, with a weighted mean of 19.15 ng/mL (weighted standard deviation 11.59 ng/mL). Country-wise analysis showed that hypovitaminosis D in Afghanistan was the highest [96.2%; 95% CI: 91% to 99%], followed by Pakistan [94%; 95% CI: 90% to 96%], India [64%; 95% CI: 46% to 79%], Bangladesh [35.48%; 95% CI: 32% to 39%], Nepal [35%; 95% CI: 1% to 83%], and Sri Lanka [25%; 95% CI: 16% to 36%]. Age group analyses revealed that hypovitaminosis D was most prevalent among neonates [85%; 95% CI: 76% to 91%], followed by school-going children [57%; 95% CI: 33% to 80%], and preschool children [55%; 95% CI: 35% to 75%].

Conclusion

This study generates quantitative evidence and specific extent of hypovitaminosis D in the South Asian countries as a public health concern. Being the first systematic review for this region, results from this study will create awareness and will facilitate adopting mitigation strategies by the policymakers and the governments to address this problem.

Supplementary Information

The online version contains supplementary material available at 10.1186/s41043-022-00287-w.

Effects of repeated infections with non-typeable Haemophilus influenzae on lung in vitamin D deficient and smoking mice

Background

In chronic obstructive pulmonary disease (COPD), exacerbations cause acute inflammatory flare-ups and increase the risk for hospitalization and mortality. Exacerbations are common in all disease stages and are often caused by bacterial infections e.g., non-typeable Heamophilus influenzae (NTHi). Accumulating evidence also associates vitamin D deficiency with the severity of COPD and exacerbation frequency. However, it is still unclear whether vitamin D deficiency when combined with cigarette smoking would worsen and prolong exacerbations caused by repeated infections with the same bacterial strain.

Methods

Vitamin D sufficient (VDS) and deficient (VDD) mice were exposed to nose-only cigarette smoke (CS) for 14 weeks and oropharyngeally instilled with NTHi at week 6, 10 and 14. Three days after the last instillation, mice were assessed for lung function, tissue remodeling, inflammation and immunity. The impact of VDD and CS on inflammatory cells and immunoglobulin (Ig) production was also assessed in non-infected animals while serum Ig production against NTHi and dsDNA was measured in COPD patients before and 1 year after supplementation with Vitamin D3.

Results

VDD enhanced NTHi eradication, independently of CS and complete eradication was reflected by decreased anti-NTHi Ig’s within the lung. In addition, VDD led to an increase in total lung capacity (TLC), lung compliance (Cchord), MMP12/TIMP1 ratio with a rise in serum Ig titers and anti-dsDNA Ig’s. Interestingly, in non-infected animals, VDD exacerbated the CS-induced anti-NTHi Ig’s, anti-dsDNA Ig’s and inflammatory cells within the lung. In COPD patients, serum Ig production was not affected by vitamin D status but anti-NTHi IgG increased after vitamin D3 supplementation in patients who were Vitamin D insufficient before treatment.

Conclusion

During repeated infections, VDD facilitated NTHi eradication and resolution of local lung inflammation through production of anti-NTHi Ig, independently of CS whilst it also promoted autoantibodies. In COPD patients, vitamin D supplementation could be protective against NTHi infections in vitamin D insufficient patients. Future research is needed to decipher the determinants of dual effects of VDD on adaptive immunity.

Trail registration

ClinicalTrials, NCT00666367. Registered 23 April 2008, https://www.clinicaltrials.gov/ct2/show/study/NCT00666367.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-022-01962-6.

Effects of Vitamin D supplementation on resolution of fever and cough in children with pulmonary tuberculosis: A randomized double-blind controlled trial in Indonesia

Background

Various studies in adults have shown a strong association between vitamin D and tuberculosis (TB), both in terms of vitamin D status and the benefits of vitamin D in managing TB. Studies on vitamin D and its relationship with childhood TB still lack in Indonesia as a country with the second-highest TB incidence globally. This study evaluated the effect of vitamin D supplementation on resolution of cough and fever in Indonesian children with pulmonary TB.

Methods

We conducted a randomized controlled trial of vitamin D supplementation in children with pulmonary TB and vitamin D insufficiency. Patients were randomly allocated with 1:1 ratio to receive either 1000 IU vitamin D or placebo daily after starting standard TB treatment. The primary outcome in this study was the resolution of fever and cough symptoms reviewed weekly after starting the treatment until the symptoms are resolved. The secondary outcome in this study was 25-hydroxyvitamin D serum level and nutritional status which was reviewed at the end of the trial. Intention to treat analyses were applied. Differences in clinical outcomes between two groups were calculated using Mann-Whitney U test or χ² test, where appropriate.

Findings

A total of 84 patients met the inclusion criteria, aged 6 to 18 years old, newly diagnosed with pulmonary TB and vitamin D insufficiency. Eighty patients (95,2%) completed the six months follow-up. Faster resolution of fever, cough, improved malnutrition status, and higher vitamin D level were found in the intervention group compared to the placebo group (all P < 0.001).

Conclusions

Vitamin D is beneficial in improving fever and cough resolution, and improving nutritional status in children with pulmonary TB and vitamin D insufficiency. Determination of adequate supplementation levels of more than 1000 IU requires further research to achieve normal vitamin D levels during the duration of treatment for pulmonary TB in children.

Trial registration

ClinicalTrials.gov (NCT05073965).

Vitamin D and the risk of latent tuberculosis infection: a systematic review and meta-analysis

Objective

Latent tuberculosis infection (LTBI) may be a risk of developing tuberculosis (TB) and thus a health hazard. The aim of this meta-analysis is to explore the association between vitamin D and LTBI.

Methods

Databases including PubMed, Embase, Scopus, and ProQuest were electronically searched to identify observational or interventional studies that reported the association between vitamin D and LTBI. The retrieval time is limited from inception to 30 September 2021. Two reviewers independently screened literature, extracted data, and assessed risk bias of included studies. Meta-analysis was performed by using STATA 12.0 software.

Results

A total of 5 studies involving 2 case–control studies and 3 cohort studies were included. The meta-analysis result showed that the risk of LTBI among individuals was not associated with high vitamin D level (OR 0.51, 95% CI 0.05–5.65, P = 0.58). The result from cohort studies also suggested that relatively high vitamin D level was not a protective factor for LTBI (RR = 0.56, 95%CI 0.19–1.67, P = 0.300).

Conclusions

Our meta-analysis suggested that serum vitamin D levels were not associated with incidence of LTBI, and relatively high serum vitamin D level was not a protective factor for LTBI. Further RCTs are needed to verify whether sufficient vitamin D levels and vitamin D supplementation reduces the risk of LTBI.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-022-01830-5.

25-Hydroxyvitamin D levels among 2-year-old children: findings from the Japan environment and Children's study (JECS)

Background

The study aim was to obtain epidemiological data on vitamin D levels for the pediatric population in Japan. We assessed the prevalence of vitamin D deficiency and insufficiency in 2-year-old Japanese children using data from a large ongoing birth cohort study.

Methods

Data for analysis was obtained from the Japan Environment and Children’s Study (JECS) and a Sub-Cohort Study (SCS) of JECS. We evaluated the children’s serum 25(OH) D levels by 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentiles, and the rates of vitamin D deficiency or insufficiency. We also presented a weighted prevalence rate for vitamin D deficiency or insufficiency among all children in JECS.

Results

After excluding children with missing 25(OH)D2 or 25(OH)D3 data, we analyzed 4655 remaining children, of whom 24.7% (95% CI, 23.5–26.0%) had vitamin D deficiency (< 20 ng/mL), and 51.3% (95% CI, 49.8–52.7%) were at risk of vitamin D insufficiency (20–30 ng/mL). The estimated prevalence of vitamin D deficiency and insufficiency among all children in JECS were 25.4% (95% CI, 24.1–26.7%) and 50.9% (95% CI, 49.4–52.4%). Vitamin D deficiency was found in 22.9% of boys and 26.5% of girls. Median serum 25(OH) D concentrations were lower among participants measured during winter and spring than among those measured in summer and autumn. The highest rate of vitamin D deficiency was observed in Hokkaido, the northernmost prefecture of Japan.

Conclusion

We analyzed data on serum 25(OH) D levels from a birth cohort study and found that vitamin D deficiency and insufficiency are very common among 2-year-old Japanese children. Sex, season, and latitude affect serum 25(OH) D concentrations.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-021-03005-3.

Transcriptome-Wide Profile of 25-Hydroxyvitamin D3 in Primary Immune Cells from Human Peripheral Blood

Vitamin D₃ is an essential micronutrient mediating pleiotropic effects in multiple tissues and cell types via its metabolite 1α,25-dihydroxyvitamin D₃ (1,25(OH)₂D₃), which activates the transcription factor vitamin D receptor. In this study, we used peripheral blood mononuclear cells (PBMCs) obtained from five healthy adults and investigated transcriptome-wide, whether the precursor of 1,25(OH)₂D₃, 25-hydroxyvitamin D₃ (25(OH)D₃), has gene regulatory potential on its own. Applying thresholds of >2 in fold change of gene expression and <0.05 as a false discovery rate, in this ex vivo approach the maximal physiological concentration of 25(OH)D₃ (250 nM (nmol/L)) none of the study participants had a significant effect on their PBMC transcriptome. In contrast, 1000 and 10,000 nM 25(OH)D₃ regulated 398 and 477 genes, respectively, which is comparable to the 625 genes responding to 10 nM 1,25(OH)₂D₃. The majority of these genes displayed specificity to the tested individuals, but not to the vitamin D metabolite. Interestingly, the genes MYLIP (myosin regulatory light chain interacting protein) and ABCG1 (ATP binding cassette subfamily G member 1) showed to be specific targets of 10,000 nM 25(OH)D₃. In conclusion, 100- and 1000-fold higher 25(OH)D₃ concentrations than the reference 10 nM 1,25(OH)₂D₃ are able to affect the transcriptome of PBMCs with a profile comparable to that of 1,25(OH)₂D₃.

Potential Role of Vitamins A, B, C, D and E in TB Treatment and Prevention: A Narrative Review

(1) Background: Tuberculosis (TB) is one of the world's top infectious killers, in fact every year 10 million people fall ill with TB and 1.5 million people die from TB. Vitamins have an important role in vital functions, due to their anti-oxidant, pro-oxidant, anti-inflammatory effects and to metabolic functions. The aim of this review is to discuss and summarize the evidence and still open questions regarding vitamin supplementation as a prophylactic measure in those who are at high risk of Mycobacterium tuberculosis (MTB) infection and active TB; (2) Methods: We conducted a search on PubMed, Scopus, Google Scholar, EMBASE, Cochrane Library and WHO websites starting from March 1950 to September 2021, in order to identify articles discussing the role of Vitamins A, B, C, D and E and Tuberculosis; (3) Results: Supplementation with multiple micronutrients (including zinc) rather than vitamin A alone may be more beneficial in TB. The WHO recommend Pyridoxine (vitamin B6) when high-dose isoniazid is administered. High concentrations of vitamin C sterilize drug-susceptible, MDR and extensively drug-resistant MTB cultures and prevent the emergence of drug persisters; Vitamin D suppresses the replication of mycobacterium in vitro while VE showed a promising role in TB management as a result of its connection with oxidative balance; (4) Conclusions: Our review suggests and encourages the use of vitamins in TB patients. In fact, their use may improve outcomes by helping both nutritionally and by interacting directly and/or indirectly with MTB. Several and more comprehensive trials are needed to reinforce these suggestions.

High prevalence of vitamin D deficiency among the South Asian adults: a systematic review and meta-analysis

Background

Vitamin-D deficiency is linked to a wide range of chronic and infectious diseases. Body of literature suggested that the prevalence of this deficiency can have geographical variation. Although vitamin D deficiency is frequently reported in the South Asian population, the scarcity of systematic reviews and meta-analysis means the true extent of the disease and the underlying factors causing it are poorly characterized.

Methods

A systematic search was performed using two databases (PubMed and Scopus) and one search engine (Google Scholar) for original studies on the South Asian population (published from January 1, 2001, to December 31, 2019). Following the search, a random effect meta-analysis was performed to calculate population-level weighted average, the pooled prevalence of deficiency, and heterogeneity of vitamin D among different countries and genders; in addition to South Asia as a whole.

Results

Our study, based on our selection criteria was narrowed down to a total of 44,717 participants; which spanned over 65 studies from five South Asian countries. Overall, the pooled prevalence of deficiency was 68% [95% CI: 64 to 72%] with significant heterogeneity (I² = 98%; p = 0.00). The average level of vitamin D ranged from 4.7 to 32 ng/mL, with a weighted mean of 19.15 ng/mL (weighted standard deviation 11.59 ng/mL). The highest prevalence of vitamin D deficiency was found in Pakistan (73%;95% CI: 63 to 83%) followed by Bangladesh (67%; 95% CI: 50 to 83%), India (67%; 95% CI: 61 to 73%), Nepal (57%; 95% CI: 53 to 60%) and Sri Lanka (48%; 95% CI: 41 to 55%), respectively. This finding indicated a high degree of heterogeneity among the population. (I² = 98.76%), Furthermore, a gender-wise analysis suggested that in South Asia, the prevalence of vitamin D deficiency was higher in females than males.

Conclusion

Our findings reveal highly prevalent and variable vitamin D deficiency among the adults of different South Asian countries. Findings from this review would be helpful to generate hypotheses and explore the factors affecting the inter-country variability, alongside strengthening evidence for governments to prioritize mitigation strategies in this region.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-11888-1.

ROLE OF VITAMIN D SUPPLEMENTATION IN THE PREVENTION OF INFECTION AND SEVERE COURSE IN COVID-19: TESTING THE HYPOTHESIS

The coronavirus disease 2019 (COVID-19) pandemic has disrupted the normal activities of various settings, including clinics, laboratories, and libraries. As the world deals with the fast-mutating causative virus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), apart from the search for the best vaccine candidate, efforts towards repurposing existing molecules to save lives must continue. Considerable interest has centered around the implications of vitamin D deficiency and its supplementation on the outcomes in patients with COVID-19. We hypothesize that vitamin D supplementation has the potential to confer protection against SARS-CoV-2 infection and a severe COVID-19 course. Various animal, human observational as well as interventional studies have shown a protective role of vitamin D in COVID-19. More robustly designed studies where vitamin D is supplemented prophylactically and administered to those already infected are needed to determine the precise contribution of this supplementation in preventing SARS-CoV-2 infection and modifying the course of COVID-19.

A scoping review on climate change and tuberculosis

Climate change is a global public health challenge. The changes in climatic factors affect the pattern and burden of tuberculosis, which is a worldwide public health problem affecting low and middle-income countries. However, the evidence related to the impact of climate change on tuberculosis is few and far between. This study is a scoping review following a five-stage version of Arksey and O'Malley's method. We searched the literature using the keywords and their combination in Google scholar, and PubMed. Climate change affects tuberculosis through diverse pathways: changes in climatic factors like temperature, humidity, and precipitation influence host response through alterations in vitamin D distribution, ultraviolet radiation, malnutrition, and other risk factors. The rise in extreme climatic events induces population displacement resulting in a greater number of vulnerable and risk populations of tuberculosis. It creates a conducive environment of tuberculosis transmission and development of active tuberculosis and disrupts tuberculosis diagnosis and treatment services. Therefore, it stands to reasons that climate change affects tuberculosis, particularly in highly vulnerable countries and areas. However, further studies and novel methodologies are required to address such a complex relationship and better understand the occurrence of tuberculosis attributable to climate change.

Influence of adding vitamin D3 to standard clarithromycin-based triple therapy on the eradication rates of Helicobacter pylori infection

BACKGROUND AND STUDY AIMS

The successful eradication rates with standard clarithromycin-based triple therapy are declining concerning the high antibiotic resistance rate and adverse drug reactions. This study aims to evaluate the effect of adding 1,25-hydroxyvitamin D3 on the eradication rates of the standard clarithromycin-based triple therapy for Helicobacter pylori infection.

PATIENTS AND METHODS

This is a randomized prospective comparative study of 150 patients diagnosed with H. pylori gastritis using magnifying narrow-band imaging endoscopy and supported by a stool antigen test. Patients were divided into two groups: group A (n = 75) treated with amoxicillin, clarithromycin, and esomeprazole for 2 weeks; group B (n = 75) treated with 1,25-hydroxyvitamin D3 for 1 month plus amoxicillin, clarithromycin, and esomeprazole for 2 weeks. The H. pylori eradication rates were assessed using stool antigen test conducted 4 weeks after the end of therapy. Furthermore, the H. pylori eradication rates were assessed with per-protocol (PP) and intention-to-treat (ITT) analyses.

RESULTS

The current results showed that H. pylori eradication was achieved in 46 of 62 (74.19%) and 46 of 75 (61.33%) patients via PP and ITT analyses, respectively, in group A. However, eradication was achieved in 60 of 68 (88.23%) and 60 of 75 (80%) patients via PP and ITT analyses, respectively, in group B. Therefore, the H. pylori eradication rates in the group where vitamin D3 was added to the clarithromycin-based triple therapy were significantly higher than in the other groups (p = 0.012 and p = 0.029 in ITT and PP analyses, respectively).

CONCLUSIONS

Adding vitamin D3 to the standard clarithromycin-based triple therapy could provide an additional advantage to achieve significantly higher eradication rates for H. pylori infection.

Association of Vitamin D Deficiency With Pulmonary Tuberculosis: A Systematic Review and Meta-Analysis

Pulmonary tuberculosis, caused by Mycobacterium tuberculosis, is a significant public health issue, especially in developing countries, affecting millions of people every year. Despite the development of many antitubercular antibiotics and increased awareness of preventive methods, it is still a major cause of mortality worldwide. Vitamin D, a micronutrient known to have a major role in bone and calcium metabolism, has also shown its immunomodulatory effects to suppress mycobacterial growth. We conducted a systematic review and meta-analysis of the available evidence to explore the association between vitamin D levels and tuberculosis. We performed a systematic search for articles from inception to May 2021 in multiple databases. We included 26 studies in our qualitative synthesis and 12 studies in meta-analysis or quantitative synthesis. In our meta-analysis, we used a random-effect model to calculate the odds ratio (OR) of vitamin D deficiency in tuberculosis patients compared to the healthy controls. On pooled analysis, we found that the odds of the participants having vitamin D deficiency was 3.23 times more in tuberculosis patients compared to the healthy group (OR=3.23, CI = 1.91-5.45, p<0.0001). Thus, we concluded that there is an association between low levels of vitamin D and tuberculosis infections. We suggest conducting long-term prospective cohort studies in tuberculosis endemic countries to better understand the causal relationship between vitamin D deficiency and tuberculosis.

Impact of vitamin D status and cathelicidin antimicrobial peptide on adults with active pulmonary TB globally: A systematic review and meta-analysis

BACKGROUND

Tuberculosis remains a global threat and a public health problem that has eluded attempts to eradicate it. Low vitamin D levels have been identified as a risk factor for tuberculosis infection and disease. The human cathelicidin LL-37 has both antimicrobial and immunomodulatory properties and is dependent on vitamin D status. This systematic review attempts to compare vitamin D andLL-37 levels among adult pulmonary tuberculosis patients to non-pulmonary TB individuals between 16-75 years globally and to determine the association between vitamin D and cathelicidin and any contributing factor among the two study groups.

METHODS/DESIGN

We performed a search, through PubMed, HINARI, Google Scholar, EBSCOhost, and databases. A narrative synthesis through evaluation of vitamin D and LL-37 levels, the association of vitamin D and LL-37, and other variables in individual primary studies were performed. A random-effect model was performed and weighted means were pooled at a 95% confidence interval. This protocol is registered under the International Prospective Register of Systematic Reviews (PROSPERO), registration number CRD42019127232.

RESULTS

Of the 2507 articles selected12 studies were eligible for the systematic review and of these only nine were included in the meta-analysis for vitamin D levels and six for LL-37 levels. Eight studies were performed in Asia, three in Europe, and only one study in Africa. The mean age of the participants was 37.3±9.9 yrs. We found low vitamin D and high cathelicidin levels among the tuberculosis patients compared to non-tuberculosis individuals to non-tuberculosis. A significant difference was observed in both vitamin D and LL-37 levels among tuberculosis patients and non-tuberculosis individuals (p = < 0.001).

CONCLUSION

This study demonstrated that active pulmonary tuberculosis disease is associated with hypovitaminosis D and elevated circulatory cathelicidin levels with low local LL-37 expression. This confirms that vitamin D status has a protective role against tuberculosis disease.

Reasons to avoid vitamin D deficiency during COVID-19 pandemic

The effects of vitamin D on the musculoskeletal system are well established. Its deficiency causes osteomalacia, secondary hyperparathyroidism, and an increased risk for fractures and falls. However, clinical and experimental evidence points to extra-skeletal actions of vitamin D, including on immune and respiratory systems. Thus, during this COVID-19 pandemic, a possible deleterious role of vitamin D deficiency has been questioned. This paper aims to present a brief review of the literature and discuss, based on evidence, the role of vitamin D in the lung function and in the prevention of respiratory infections. Relevant articles were searched in the databases MEDLINE/PubMed and SciELO/LILACS. The mechanisms of vitamin D action in the immune system response will be discussed. Clinical data from systematic reviews and meta-analyses show benefits in the prevention of respiratory infections and improvement of pulmonary function when vitamin D-deficient patients are supplemented. At the time of writing this paper, no published data on vitamin D supplementation for patients with COVID-19 have been found. Vitamin D supplementation is recommended during this period of social isolation to avoid any deficiency, especially in the context of bone outcomes, aiming to achieve normal values of 25(OH)D. The prevention of respiratory infections and improvement of pulmonary function are additional benefits observed when vitamin D deficiency is treated. Thus far, any protective effect of vitamin D specifically against severe COVID-19 remains unclear. We also emphasize avoiding bolus or extremely high doses of vitamin D, which can increase the risk of intoxication without evidence of benefits.

The relationship between seasonality, latitude and tuberculosis notifications in Pakistan

Background

Pakistan ranks amongst the top 20 highest burden tuberculosis (TB) countries in the world. Approximately 369,548 cases of TB (all forms) were notified in 2018, with an estimated incidence of 265 per 100,000 people per year. In other settings, TB has been shown to demonstrate seasonal variation, with higher incidence in the spring/summer months and lower incidence in the autumn/winter; the amplitude of seasonal variation has also been reported to be higher with increasing distance from the equator.

Methods

Notifications of newly-diagnosed pulmonary and extrapulmonary TB cases were obtained for 139 districts in Pakistan from 2011 to 2017. Data were provided by the Pakistan National TB Control Programme, Islamabad, Pakistan. Statistical analyses were performed to determine whether there was seasonal variation in TB notifications in Pakistan; whether the amplitude of seasonal variation in TB notifications varied according to latitude; whether the amplitude of seasonal variation of TB in Pakistan differed between extrapulmonary TB vs. pulmonary TB. To assess the quarterly seasonality of TB, we used the X-13-ARIMA-SEATS seasonal adjustment programme from the United States Census Bureau. The mean difference and corresponding 95% confidence intervals of seasonal amplitudes between different latitudes and clinical phenotype of TB were estimated using linear regression.

Results

TB notifications were highest in quarter 2, and lowest in quarter 4. The mean amplitude of seasonal variation was 25.5% (95% CI 25.0 to 25.9%). The mean seasonal amplitude of TB notifications from latitude 24.5°N- < 26.5°N was 29.5% (95% CI 29.3 to 29.7%) whilst the mean seasonal amplitude of TB notifications from latitude 34.5°N - < 36.5°N was 21.7% (95% CI 19.6 to 23.9%). The mean seasonal amplitude of TB notifications across Pakistan between latitudes 24.5°N to 36.5°N reached statistically significant difference (p < 0.001). The amplitude of seasonal variation was greater for extrapulmonary TB (mean seasonal amplitude: 32.6, 95% CI 21.4 to 21.8%) vs. smear positive pulmonary TB mean seasonal amplitude: 21.6, 95% CI 32.1 to 33.1%), p < 0.001.

Conclusion

TB notifications in Pakistan exhibit seasonal variation with a peak in quarter 2 (April–June) and trough in quarter 4 (October–December). The amplitude of seasonality decreases with increasing latitude, and is more pronounced for extrapulmonary than for pulmonary TB.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-05899-x.

Serum vitamin D receptor and High Mobility Group Box-1 (HMGB1) levels in HIV-infected patients with different immunodeficiency status: A cross-sectional study

Background

HIV-AIDS patients typically have hypovitaminosis D. Vitamin D is a key mediator in inflammatory and infectious diseases, which VDR mediates its biological effect. High-mobility group box 1 protein (HMGB1) modulates HIV-1 replication in vitro. Vitamin D played a role in inhibiting HMGB1 secretion in the animal study.

Objectives

This study aimed to examine differences and correlation of vitamin D receptor and HMGB1 protein levels in HIV patients with mild and severe immunodeficiency and healthy control participants.

Methods

This study using a cross-sectional design conducted at Volunteer Counseling and Testing (VCT) Clinic in Mataram, West Nusa Tenggara, Indonesia, from January to June 2020. Three groups of study participants were classified as HIV patients with severe immune deficiency (SID), HIV patients with mild immune deficiency (MID), and healthy controls (HC).

Results

Mean level of vitamin D receptor in SID HIV group was 25.89 ± 3.95 ng/ml, lower than those in MID-HIV group; 33.72 ± 1.69 ng/ml and in HC group; 50.65 ± 3.64 ng/ml. Mean levels of HMGB1 protein in the SID HIV group were 3119.81 ± 292.38 pg/ml higher than those in the MID HIV group 1553.55 ± 231.08 pg/ml and HC 680.82 ± 365.51 pg/ml. There was a significant and strong negative correlation (r = −0.932) between vitamin D receptor and HMGB1 levels (p < 0.01).

Conclusions

Strong negative correlation between VDR and HMGB1 in different immunodeficiency statuses suggesting an important role of vitamin D in inflammation control in HIV infection. However, it needs to be confirmed in a further prospective study.

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Study was conducted in developing area in West Nusa Tenggara, Indonesia.

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This study consists of 3 groups with different immune status.

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This was the first study that correlates VDR and HMGB1 in HIV-infected patients.

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Strong correlation suggests association of VDR and HMGB1with HIV infection.

Host-directed therapy to combat mycobacterial infections

Upon infection, mycobacteria, such as Mycobacterium tuberculosis (Mtb) and nontuberculous mycobacteria (NTM), are recognized by host innate immune cells, triggering a series of intracellular processes that promote mycobacterial killing. Mycobacteria, however, have developed multiple counter‐strategies to persist and survive inside host cells. By manipulating host effector mechanisms, including phagosome maturation, vacuolar escape, autophagy, antigen presentation, and metabolic pathways, pathogenic mycobacteria are able to establish long‐lasting infection. Counteracting these mycobacteria‐induced host modifying mechanisms can be accomplished by host‐directed therapeutic (HDT) strategies. HDTs offer several major advantages compared to conventional antibiotics: (a) HDTs can be effective against both drug‐resistant and drug‐susceptible bacteria, as well as potentially dormant mycobacteria; (b) HDTs are less likely to induce bacterial drug resistance; and (c) HDTs could synergize with, or shorten antibiotic treatment by targeting different pathways. In this review, we will explore host‐pathogen interactions that have been identified for Mtb for which potential HDTs impacting both innate and adaptive immunity are available, and outline those worthy of future research. We will also discuss possibilities to target NTM infection by HDT, although current knowledge regarding host‐pathogen interactions for NTM is limited compared to Mtb. Finally, we speculate that combinatorial HDT strategies can potentially synergize to achieve optimal mycobacterial host immune control.

Perspective: Vitamin D deficiency and COVID-19 severity - plausibly linked by latitude, ethnicity, impacts on cytokines, ACE2 and thrombosis

BACKGROUND

SARS-CoV-2 coronavirus infection ranges from asymptomatic through to fatal COVID-19 characterized by a 'cytokine storm' and lung failure. Vitamin D deficiency has been postulated as a determinant of severity.

OBJECTIVES

To review the evidence relevant to vitamin D and COVID-19.

METHODS

Narrative review.

RESULTS

Regression modelling shows that more northerly countries in the Northern Hemisphere are currently (May 2020) showing relatively high COVID-19 mortality, with an estimated 4.4% increase in mortality for each 1 degree latitude north of 28 degrees North (P = 0.031) after adjustment for age of population. This supports a role for ultraviolet B acting via vitamin D synthesis. Factors associated with worse COVID-19 prognosis include old age, ethnicity, male sex, obesity, diabetes and hypertension and these also associate with deficiency of vitamin D or its response. Vitamin D deficiency is also linked to severity of childhood respiratory illness. Experimentally, vitamin D increases the ratio of angiotensin-converting enzyme 2 (ACE2) to ACE, thus increasing angiotensin II hydrolysis and reducing subsequent inflammatory cytokine response to pathogens and lung injury.

CONCLUSIONS

Substantial evidence supports a link between vitamin D deficiency and COVID-19 severity but it is all indirect. Community-based placebo-controlled trials of vitamin D supplementation may be difficult. Further evidence could come from study of COVID-19 outcomes in large cohorts with information on prescribing data for vitamin D supplementation or assay of serum unbound 25(OH) vitamin D levels. Meanwhile, vitamin D supplementation should be strongly advised for people likely to be deficient.

The Assessment of Vitamin D Serum Level in Patients With Pulmonary and Extra-Pulmonary Tuberculosis in Karaj, Iran, During 2017-2018

Background: It is important to determine the type of tuberculosis and its related factors in order for effectively treating a disease and reducing its side effects in the society. Objective: This study aimed to determine vitamin D level in patients with pulmonary and extra-pulmonary tuberculosis in Karaj, Iran in 2017-2018. Materials and Methods: In this observational study, 102 patients suffering from pulmonary and extra-pulmonary tuberculosis disease were availably selected in Karaj, Iran in 2017-2018. They were examined and, then, their vitamin D level were assessed and compared according to the type of tuberculosis. Results: The study results showed that vitamin D level was normal in 39.2% of the case study population, but it was abnormal in 60.8% of it (18.6% deficiency and 42.2% insufficiency). Vitamin D deficiency was 15.8% in pulmonary tuberculosis patients and it was 22.2% in extra-pulmonary tuberculosis ones, showing no significant difference (P>0.05) statistically. Conclusion: According to the obtained results, hypovitaminosis-D was detected in more than half of the patients with pulmonary and extra pulmonary tuberculosis, which was not associated with the type of tuberculosis. Seemingly, the patients needed the same amount of – or even more – food, medical supplements, sports, and sunlight compared to healthy people.

Adaptation and co-adaptation of skin pigmentation and vitamin D genes in native Americans

We carried out an exhaustive review regarding human skin color variation and how much it may be related to vitamin D metabolism and other photosensitive molecules. We discuss evolutionary contexts that modulate this variability and hypotheses postulated to explain them; for example, a small amount of melanin in the skin facilitates vitamin D production, making it advantageous to have fair skin in an environment with little radiation incidence. In contrast, more melanin protects folate from degradation in an environment with a high incidence of radiation. Some Native American populations have a skin color at odds with what would be expected for the amount of radiation in the environment in which they live, a finding challenging the so-called "vitamin D-folate hypothesis." Since food is also a source of vitamin D, dietary habits should also be considered. Here we argue that a gene network approach provides tools to explain this phenomenon since it indicates potential alleles co-evolving in a compensatory way. We identified alleles of the vitamin D metabolism and pigmentation pathways segregated together, but in different proportions, in agriculturalists and hunter-gatherers. Finally, we highlight how an evolutionary approach can be useful to understand current topics of medical interest.

Common and personal target genes of the micronutrient vitamin D in primary immune cells from human peripheral blood

Vitamin D is essential for the function of the immune system. In this study, we treated peripheral blood mononuclear cells (PBMCs) of healthy adults with the biologically active form of vitamin D₃, 1α,25-dihydroxyvitamin D₃ (1,25(OH)₂D₃) using two different approaches: single repeats with PBMCs obtained from a cohort of 12 individuals and personalized analysis based on triplicates of five study participants. This identified 877 (cohort approach) and 3951 (personalized approach) genes that significantly (p < 0.05) changed their expression 24 h after 1,25(OH)₂D₃ stimulation. From these, 333 and 1232 were classified as supertargets, a third of which were identified as novel. Individuals differed largely in their vitamin D response not only by the magnitude of expression change but also by their personal selection of (super)target genes. Functional analysis of the target genes suggested the overarching role of vitamin D in the regulation of metabolism, proliferation and differentiation, but in particular in the control of functions mediated by the innate and adaptive immune system, such as responses to infectious diseases and chronic inflammatory disorders. In conclusion, immune cells are an important target of vitamin D and common genes may serve as biomarkers for personal responses to the micronutrient.

The association between vitamin D deficiency and extrapulmonary tuberculosis: Case-control study

Tuberculosis remains a public health issue worldwide. Identifying its risk factors, such as vitamin D deficiency, is mandatory so as to target the preventive strategies. We aimed to study the association between vitamin D deficiency and extrapulmonary tuberculosis. We conducted a case-control study including all cases of extrapulmonary tuberculosis hospitalized in the infectious diseases department over a two-year period from April 2017 until April 2019. We included 45 cases of extrapulmonary tuberculosis and 45 controls matched by gender and age. Vitamin D deficiency was significantly more frequent among cases (80% vs 37.7%; p < 0.001), with an odds ratio (OR) of 6.5 (IC95% = 2.5-16). The mean levels of vitamin D were significantly lower among cases (11.9 ± 8.8 vs 22.3 ± 11 ng/mL; p < 0.001). In the multivariate analysis, we found that vitamin D deficiency was an independent predictor of extrapulmonary tuberculosis (OR = 6.13; p < 0.001). The cutoff value of vitamin D predictor of extrapulmonary tuberculosis was 18.5 ng/mL which was associated with a sensitivity of 80% and a specificity of 62%. Our study provides strong evidence that vitamin D deficiency was an independent predictor of extrapulmonary tuberculosis. More studies are needed in order to evaluate the potential preventive role of vitamin D and the benefit of possible supplementation.