Small Intestinal Bacterial Overgrowth in Subclinical Hypothyroidism of Pregnant Women

OBJECTIVE

To evaluate the small intestinal bacterial overgrowth (SIBO) of subclinical hypothyroidism of pregnant women, and explore their possible relevance.

METHODS

In total, 224 pregnant women with subclinical hypothyroidism during pregnancy (study group) and 196 pregnant women whose thyroid function was normal (control group) were enrolled in this study. Lactulose-based hydrogen and methane breath test was performed to evaluate the growth of intestinal bacteria. The serum-free thyroid hormone (FT4), thyroid-stimulating hormone (TSH), thyroid peroxidase antibody (TPOAb), body mass index (BMI) and gastrointestinal symptoms were detected and recorded.

RESULTS

The positive rates of SIBO were 56.7% and 31.6% in study group and control group, respectively. The levels of C response protein (CRP), abdominal distension and constipation in study group were higher than those in the control group. The risk of abdominal distension and constipation in SIBO-positive pregnant women were higher than that in SIBO-negative pregnant women, and the BMI of SIBO-positive patients in the two groups was lower than that of SIBO-negative patients in each group. In addition, the TPOAb-positive rate and TSH levels were higher but the FT4 level was lower in SIBO-positive patients compared to SIBO-negative patients in study group.

CONCLUSION

The occurrence of subclinical hypothyroidism is related to SIBO, and the excessive growth of small intestinal bacteria may affect gastrointestinal symptoms.

CLINICAL TRIAL

http://www.chictr.org.cn/index.aspx, identifier ChiCTR1900026326.

Plasma Lipid Profile and Intestinal Microflora in Pregnancy Women With Hypothyroidism and Their Correlation With Pregnancy Outcomes

OBJECTIVE

To investigate the lipid profiles and intestinal microflora in pregnant patients with hypothyroidism and their correlation with pregnancy outcomes.

METHODS

In total, 27 pregnant women with hypothyroidism (study case) and 28 normal pregnant women (control group) were enrolled in this study. The lipid profiles and intestinal microflora in the two groups were compared using untargeted liquid chromatography-mass spectrometry (LC-MS) and 16S rRNA amplicon sequencing, respectively. The association among the differential metabolites, intestinal microflora, serological indicators and pregnancy outcomes was further analyzed.

RESULTS

Patients in study case had higher C-reactive protein (CRP) levels (P = 0.025) and lower birth weight (P=0.005) than the control group. A total of 42 differential lipid metabolites and 7 enrichment KEGG pathways were obtained between the two groups (VIP ≥ 1, P < 0.05). Ten lipid metabolites can be used as characteristic metabolites of study case, including phosphatidylcholine (PC), phosphatidylethanolamine (PE) and sphingomyelin (SM). The richness and diversity of intestinal microflora in study case were lower than those in the control group (P>0.05). LEfSe analysis revealed that patients in study case had higher abundance of Prevotella and Haemophilus and lower abundance of Blautia than the control group (P < 0.05). Blautia was positively correlated with SM and negatively correlated with PC and PE; the CRP level and Prevotella were positively correlated; the neonatal weight and PC level were negatively correlated (P < 0.05).

CONCLUSION

The lipid profile and intestinal microflora of pregnant women with hypothyroidism significantly differed from those of normal pregnant women and were associated with adverse pregnancy outcomes. The interaction between lipid metabolism and intestinal microflora may be a potential target for further studies investigating the pathogenesis of hypothyroidism during pregnancy.

Oral and intestinal microbial features in pregnant women with hypothyroidism and their correlations with pregnancy outcomes

The purpose of this study was to explore the characteristics of oral and intestinal microbiota of pregnant women with hypothyroidism during pregnancy, and to find the correlations between the changes of flora and pregnancy outcome of pregnant women with hypothyroidism during pregnancy. In this study, oral and intestinal microbial composition was surveyed by using the 16S rRNA sequencing approach in 61 pregnant women (30 with hypothyroidism and 31 normal controls). Sequentially, we validated the differential microbial features by using the quantitative real-time PCR (qPCR) approach in 10 randomly selected pregnant women (5 with hypothyroidism and 5 normal controls). Furthermore, general clinical data and serological indices were added to the analysis to examine the links between oral and intestinal microbiota and pregnancy outcomes. The 16S rRNA results showed that the relative abundances of Gammaproteobacteria were higher in pregnant women in the hypothyroidism group than in those in the control group, whereas the levels of Firmicutes were higher in the control group than in the hypothyroidism group. The serum C-reactive protein level, the weight gain during pregnancy, and the incidence of fetal distress were higher in the hypothyroidism group than in the control group. The QPCR results also showed the same changes of the intestinal microbiota in the two groups. There were significant differences in the oral and intestinal microbiota between pregnant women with hypothyroidism and normal pregnant women. The changes of microbiota is one of the factors influencing the occurrence and development of hypothyroidism during pregnancy.

The Role of Serum Procalcitonin in Predicting Bacterial Sepsis in Patients With Hypothyroidism

CONTEXT

Serum levels of procalcitonin (PCT), a protein produced by the thyroid C cells under physiologic conditions, are high during sepsis.

OBJECTIVE

To assess the test performance of serum PCT in predicting bacterial sepsis and septic shock in patients with hypothyroidism compared with those who have euthyroidism.

DESIGN AND METHODS

This retrospective study evaluated patients with no history of thyroid dysfunction (euthyroid), primary hypothyroidism [medical hypothyroidism (MH)], and postsurgical hypothyroidism from total thyroidectomy (TT) identified from a prospectively maintained database who had PCT testing from 2005 to 2018. Quick Sequential Organ Failure Assessment score ≥ 2 or positive bacterial cultures identified bacterial sepsis, and a mean arterial pressure less than 65 mm Hg or a vasopressor requirement defined septic shock. Sensitivity and specificity of PCT for evaluation of bacterial sepsis and septic shock were measured.

RESULTS

We identified 217 euthyroid patients, 197 patients with MH, and 84 patients with TT. Bacterial sepsis was found in 98 (45.2%), 92 (46.7%), and 36 (42.9%) of these patients, respectively (P > 0.05). Septic shock was identified in 13 (6.0%), 13 (6.6%), and 5 (6.0%) patients (P > 0.05), respectively. With use of a PCT cutoff of 0.5 µg/L for bacterial sepsis, the sensitivity was 59%, 61%, and 53% (P > 0.05) and specificity was 81%, 77%, and 81% (P > 0.05) for the diagnosis of bacterial sepsis in euthyroid, MH, and TT patients, respectively. With use of a PCT cutoff of 2.0 µg/L for septic shock, the sensitivity was 46%, 62%, and 63% (P > 0.05) and specificity was 86%, 82%, and 91% (P > 0.05) for the diagnosis of septic shock in these patients, respectively.

CONCLUSIONS

Despite the thyroidal origin of PCT, hypothyroidism did not affect the diagnostic performance of serum PCT levels in predicting bacterial sepsis or septic shock.

Fungal infection in a post-renal transplant patient with Diaporthe

Post-renal transplant fungal infections continue to be a major cause of mortality and morbidity. Universally reported fungi are Candida, especially Candida albicans, Cryptococcus, Aspergillus, Trichophyton rubrum and Pityriasis versicolor. Here, we report a case of infection caused by a rare fungus Diaporthe. It is an endophyte reported as plant pathogens and infrequently in humans and mammals. The patient was a renal transplant recipient on immunosuppressant. He had hypothyroidism and diagnosed with permanent pacemaker due to a complete heart block. The patient was treated with itraconazole (200 mg) successfully.

Is hypothyroidism rare in multidrug resistance tuberculosis patients on treatment? A systematic review and meta-analysis

BACKGROUND

Hypothyroidism is one of the adverse drug reactions that associated with Multidrug Resistant Tuberculosis (MDR-TB) medications. Extremely variable magnitude of hypothyroidism in MDR-TB patients has been reported from different parts of the world. However, there is no evidence that tried to estimate the pooled prevalence of hypothyroidism to confirm the rareness of hypothyroidism in MDR-TB patients on treatment. Therefore, we did a systematic review and meta-analysis to estimate the prevalence of hypothyroidism in MDR-TB patients on treatment, and to summarize the demographic and clinical characteristics of the patients.

METHODS

We conducted a systematic review and meta-analysis on studies reported around the world on the prevalence of hypothyroidism in MDR-TB patients on treatment. We searched electronic databases: PubMed/Medline, EMBASE, CINAHL, Science Direct, Academic Search Complete and Google scholar for English language articles without limiting publication year. We also reviewed the bibliographies of relevant studies and conducted an electronic search for relevant conference abstracts. Eligible studies were cross-sectional and cohort studies that included at least five participants. We used a random-effects model to estimate the pooled prevalence of hypothyroidism. The registration number of this review study protocol is CRD42018109237.

RESULTS

We included 30 studies and pooled data on a total of 6,241 MDR-TB patients. The crude prevalence of hypothyroidism was extremely heterogeneous. The pooled prevalence of hypothyroidism in MDR-TB patients on treatment was 17.0% (95% CI: 13.0-20.0). Ethionamide and para-aminosalicylic acid (PAS) were the most frequently reported drugs that associated with the occurrence of hypothyroidism.

CONCLUSION

This review revealed that hypothyroidism is not a rare adverse drug reaction in MDR-TB patients on treatment. Ethionamide and PAS were the most frequently reported drugs that associated with the occurrence of hypothyroidism. Screening of hypothyroidism in MDR-TB patients on treatment is important while targeting patients on Ethionamide and PAS based treatment regimen.

Tablet and oral liquid L-thyroxine formulation in the treatment of naïve hypothyroid patients with Helicobacter pylori infection

To compare the clinical efficacy of tablet and oral liquid L-thyroxine (LT4) formulation in naïve hypothyroid subjects with Helicobacter pylori infection. Forty-seven adult naïve hypothyroid subjects with dyspeptic symptoms were investigated with upper endoscopy and divided into: 28 patients with Helicobacter pylori infection (Group A); 15 patients without gastric alterations (group B); 4 patients with autoimmune gastritis were excluded from the study. Subjects were randomly treated with a same dose of LT4 tablet (TAB) or oral liquid formulation (SOL), for 9 months on group A and 6 months on group B. Helicobacter pylori infection was eradicated after 3 months of LT4 treatment. On group A, after 3 months (before Helicobacter pylori eradication), subjects treated with SOL showed a greater thyroid-stimulating hormone reduction (ΔTSH_3-0: TAB = -4.1 ± 4.6 mU/L; SOL = -7.7 ± 2.5 mU/L; p = 0.029) and a greater homogeneity in the thyroid-stimulating hormone values (TSH_3mo: TAB = 5.7 ± 4.9 mU/L; SOL = 4.1 ± 2.0 mU/L; p = 0.025), compared to LT4 tablet. At 9 months (after 6 months of Helicobacter pylori eradication) mean thyroid-stimulating hormone values were lower in subjects treated with LT4 tablet (TSH_9mo: TAB = 1.8 ± 1.2 mU/L; SOL = 3.2 ± 1.7 mU/L; p = 0.006). On group B no difference were observed, at each time point, in the mean thyroid-stimulating hormone values and thyroid-stimulating hormone variations between two LT4 formulations. LT4 liquid formulation may produce a better clinical response compared to the tablet formulation in hypothyroid subjects with Helicobacter pylori infection.

Infection by Cag A positive strains of Helicobacter pylori is associated with autoimmune thyroid disease in Iranian patients

BACKGROUND

Infectious agents have been suspected as a triggering factor for development of autoimmune thyroid disease (ATD). Some reports from Western countries have suggested association between Helicobacter pylori (HP) infection and ATD.

OBJECTIVE

To investigate the association of ATD with Cag A seropositivity in a population with high rate and early age of onset of HP infection.

METHODS

IgG anti HP and anti Cag A antibodies were measured in 88 patients with ATD and compared with results of 112 healthy individuals.

RESULTS

The rate of infection with HP was not significantly different in patient and control groups, but there was significant association between ATD and infection with Cag A strains (p<0.005). This association was significant for both hypothyroidism (p<0.005) and Graves' disease (p<0.02). Cag A antibody level correlated with titers of thyroid auto antibodies (p<0.001).

CONCLUSION

In a population with high rate and early age of onset of HP infection, only infection with Cag A positive strains is associated with ATD, and this may be due to immune cross-reactivity.

Association between hypothyroidism and small intestinal bacterial overgrowth

OBJECTIVES

Small intestinal bacterial overgrowth is defined as an abnormally high bacterial population level in the small intestine. Intestinal motor dysfunction associated with hypothyroidism could predispose to bacterial overgrowth. Luminal bacteria could modulate gastrointestinal symptoms and interfere with levothyroxine absorption. The aims of the present study were to assess the prevalence and clinical pattern of bacterial overgrowth in patients with a history of overt hypothyroidism and the effects of bacterial overgrowth decontamination on thyroid hormone levels.

METHODS

A total of 50 consecutive patients with a history of overt hypothyroidism due to autoimmune thyroiditis was enrolled. Diagnosis of bacterial overgrowth was based on positivity to a hydrogen glucose breath test. Bacterial overgrowth positive patients were treated with 1,200 mg rifaximin each day for a week. A glucose breath test, gastrointestinal symptoms, and thyroid hormone plasma levels were reassessed 1 month after treatment.

RESULTS

A total of 27 patients with a history of hypothyroidism demonstrated a positive result to the breath test (27 of 50, 54%), compared with two in the control group (two of 40, 5%). The difference was statistically significant (P < 0.001). Abdominal discomfort, flatulence, and bloating were significantly more prevalent in the bacterial overgrowth positive group. These symptoms significantly improved after antibiotic decontamination. Thyroid hormone plasma levels were not significantly affected by successful bacterial overgrowth decontamination.

CONCLUSIONS

The history of overt hypothyroidism is associated with bacterial overgrowth development. Excess bacteria could influence clinical gastrointestinal manifestations. Bacterial overgrowth decontamination is associated with improved gastrointestinal symptoms. However, fermenting carbohydrate luminal bacteria do not interfere with thyroid hormone levels.

Toll-like receptor-MyD88 and Fc receptor pathways of mast cells mediate the thyroid dysfunctions observed during nonthyroidal illness

Bacterial infections and other pathologic conditions induce complex dysfunctions of the hypothalamic-pituitary-thyroid axis, collectively known as nonthyroidal illness (NTI). To explore the pathogenesis of bacterial NTI, we injected Mycobacterium tuberculosis extracts or Escherichia coli LPS in mice lacking key components of the Toll-like receptor or crystallizable fragment (Fc) receptor pathways. In wild-type mice, the bacterial components induced a hypothyroidism characterized by elements of both hypothalamic and thyroidal dysfunction. This NTI hypothyroidism did not develop in mice lacking the MyD88 adaptor or in those with a reduced number of mast cells. The hypothyroid responsiveness to LPS, however, was restored upon reconstitution with mast cells derived from the bone marrow of wild-type donors. In addition to bacterial components, whole immunoglobulins induced NTI hypothyroidism in wild-type mice, but not in those lacking activating Fc receptors or mast cells. The study demonstrates a link between Toll-like and Fc receptor signaling and thyroid gland function, uncovering a role of mast cells in murine NTI.

Bacterial Pituitary Abscess: an Unusual Cause of Panhypopituitarism

OBJECTIVE

To describe a case of primary bacterial pituitary abscess manifesting as hypopituitarism.

METHODS

We present the case history, hormonal and bacteriologic data, and findings on imaging studies in a 34-year-old man.

RESULTS

The patient had an 8-month history of intermittent fever, headache, nausea, vomiting, and weight loss. Because a computed tomographic scan of the head showed a cystic sellar mass with ring enhancement, he was referred to our medical center. On physical examination, he showed signs of meningeal irritation and had mild hypotension. Hormonal evaluation revealed evidence of hypocortisolism, hypothyroidism, and hypogonadism. Three weeks after treatment with antibiotics and hormonal replacement, he underwent transsphenoidal surgical exploration and evacuation of purulent material from the sella. On culture, this specimen grew coagulase-negative staphylococci and Propionibacterium granulosum. Nine months later, dynamic testing showed persistent central hypocortisolism, hypothyroidism, and hypogonadism.

CONCLUSION

Bacterial pituitary abscess is rare but manifests similar to other pituitary masses with headaches, visual field defects, and hormonal disturbances. For the correct preoperative diagnosis of this condition, the physician must have a high index of suspicion, and the characteristic ring enhancement must be present on imaging studies.

Thyroid function in patients with mycetoma

Thyroid function was assessed in seventy two patients with various types of mycetoma. There was no evidence of clinical or biochemical thyroid dysfunction in these patients. The symptoms encountered in some of the mycetoma patients mimic those of hypothyroidism should be attributed to other factors possibly mental depression and apathy.

Case report: hypothyroidism due to pneumocystis carinii thyroiditis in a patient with acquired immunodeficiency syndrome

Pneumocystis carinii is the most common cause of opportunistic pulmonary infection in AIDS patients and disseminated disease is being recognized with increasing frequency. We describe a patient with cavitary pulmonary disease, lymphadenopathy, thyroiditis, and associated hypothyroidism, all a result of P. carinii. The organism was easily demonstrated in a fine-needle aspirate specimen of the thyroid. This is the second reported case of clinically apparent Pneumocystis thyroiditis and the first reported case of hypothyroidism due to an opportunistic infection in a patient with AIDS. Clinicians should be aware of this entity and request a Grocott-Gomori methenamine-silver nitrate stain of appropriate cytology specimens to make the diagnosis.

Rapid induction of hypothyroidism by an avian leukosis virus

Infection of 10-day chicken embryos with an avian leukosis virus, RAV-7, resulted in hypothyroidism within 3 weeks posthatching. Histological examination of the thyroids from infected chickens showed an extensive infiltration of lymphoblastoid cells by 7 days posthatching. Areas resembling germinal centers were present in the thyroids of infected chickens by 3 weeks posthatching. Examination of circulating thyroid and pancreas hormones showed a significant reduction in T3 and T4 levels and a trend toward higher insulin levels after 16 days posthatching. T4 supplementation of RAV-7-infected chickens alleviated some aspects of the disease syndrome but did not abrogate all symptoms. Marked involution of both bursa and thymus glands was noted. RAV-7 had an RNA genome of 8.2 kilobases and a polypeptide composition characteristic of an avian leukosis virus. The hypothyroidism followed a dose response to RAV-7 infection.