Reference values for blood count laboratory tests in the Brazilian adult population, National Health Survey

Valproic acid intoxication - The importance of toxicological analysis and correct management: A case report

Introduction

Valproic acid (VPA) is an anticonvulsant widely used in treating epilepsy which can occur cases of poisoning in overdose situations.

Case description

A 15-year-old girl purposely ingested about 100 drug tablets according to family members. Gastric lavage with activated charcoal was performed at home using a nasogastric tube and patient just was taken to the hospital around 10 h after drug ingestion, arriving in shock state. All laboratorial parameters were altered together a suspect of aspiration pneumonia with the presence of gross perihilar infiltrated in the right lung. Immunoassay screening test did not detect any substance; LC-UV detected quetiapine (> 150 ng/mL) while GC-MS determined 977.96 µg/mL of valproic acid in the patient's plasma, confirming valproic acid intoxication. Appropriate life support was performed in the patient during hospitalization; however, she died two days later, reaching her suicide.

Conclusions

Prognosis could be favorable if the patient was taken immediately to hospital emergency, considering the complexity of managing poisoning. Patient´s anamnesis must be carefully analyzed by the healthcare professional to avoid false conclusions and toxicological analysis is extremely important to clarify suspected poisoning.

Hematological parameters' reference intervals in apparently healthy individuals in Saudi Arabia: a systematic review and meta-analysis

Background

The study aimed to perform a systematic review/meta-analysis of observational studies conducted in Saudi Arabia to identify the patterns of reported hematological parameters' reference intervals (RIs).

Methods

The literature search was performed using PubMed and Google Scholar. Observational studies that reported hematological parameters measured under normal physiological conditions in apparently healthy individuals were included. Studies conducted on non-healthy individuals and/or on pregnant women; those related to basic science, methodology, physiology, and non-physiological state; and those conducted on patients having co-morbidities were excluded. Studies on the pediatric population were also excluded from the meta-analysis. The methodological quality was assessed using standard critical appraisal instruments from the Joanna Briggs Institute (JBI) Critical Appraisal Checklist. R software was used to run the random-effects models. The results were reported as weighted mean differences and 95% confidence intervals. The complete blood count (CBC) parameter means were compared by sex using an independent samples t-test.

Results

In total, 12 studies were included in the systematic review from all regions-Central (n = 5), Western (n = 5), Southern (n = 1), and Northern (n = 1). A total of eight (66%) studies focused on adults, and four (33.3%) studies reported a sample of adolescents/children. In addition, seven studies were not included in the meta-analysis for the following reasons: three studies reported only white blood cell (WBC) parameters, two studies had only abstracts available, and two studies involved newborns. High heterogeneity was demonstrated for all hematological parameters: red blood cell (RBC), hemoglobin (Hb), or mean corpuscular hemoglobin concentration (MCHC) (I2 = 100%); mean corpuscular hemoglobin (MCH) or hematocrit (HCT) (I2 = 99%); platelet (PLT) or mean corpuscular volume (MCV) (I2 = 98%); and WBC (I2 = 90%). The RBC (p = 0.009) and Hb (p = 0.0006) values were higher in the male participants. The PLT (p = <0.0001) values were higher in female participants. The remaining hematological parameters' RIs were not statistically significant.

Conclusion

The findings indicated some differences in the hematological parameters' RIs reported across Saudi Arabia. We recommend establishing hematological parameters' RIs based on the Saudi Arabian population to determine when to refer a patient with abnormal counts and to identify when to request further diagnostic work-up.

Reference intervals of hematological parameters in the Chilean adult population and the Mapuche ethnic group

Objectives

Reference intervals (RI) are an essential tool to support clinical decisions. These may have intra- and inter-individual variations associated with genetic differences and environmental factors. Given that Chile is a multiethnic territory, studying these variables is even more relevant. The purpose of this study was to establish RI for various hematological parameters in the Chilean population and the Mapuche ethnic group.

Methods

A sample of 356 adult individuals (aged 18-65 years), of which 146 belonged to the Mapuche ethnic group, was selected using the indirect a posteriori method from the database of the UC Temuco Clinical Laboratory. The analysis was conducted by sex and ethnicity. The Tukey fences method was employed to detect outliers, and the RIs were established through the non-parametric method recommended by the IFCC.

Results

The median age for the overall sample of the general population was 35 years (female) and 36 years (male). Differences (p<0.05) were found by sex in parameters dependent on hemoglobin and platelets counts. In the analysis by ethnicity, the parameters of RBC, HGB and HCT presented significant differences (p<0.0001).

Conclusions

This study shows that hematological RI vary according to sex and ethnicity, which must be considered in a multiethnic population. This understanding enhances our comprehension of the individual characteristics of each person and facilitates more accurate clinical interpretation.

Intervalos de referencia de parámetros hematológicos en población chilena adulta y en la etnia mapuche

Objetivos

Los intervalos de referencia (IR) son una herramienta esencial para apoyar la toma de decisiones clínicas. Estos pueden presentar variaciones intra e interindividuales asociadas a diferencias genéticas y factores medioambientales. Dado que la población de Chile está compuesta por múltiples grupos étnicos, estas variables adquieren aún mayor relevancia. El objetivo del presente estudio es establecer IR para diferentes parámetros hematológicos en la población chilena y la etnia mapuche.

Métodos

Se seleccionó una muestra de 356 adultos (entre 18 y 65 años), de los cuales 146 pertenecían a la etnia mapuche, utilizando el método indirecto a posteriori a partir de la base de datos del laboratorio clínico UC Temuco. El análisis se realizó considerando el sexo y la etnia. Los valores atípicos se detectaron mediante la prueba de Tukey, mientras que los IR se establecieron aplicando el método no paramétrico recomendado por la IFCC.

Resultados

La mediana de edad de la muestra global de la población general fue de 35 años en mujeres y 36 años en hombres. Se observaron diferencias estadísticamente significativas (p<0,05) por sexo en los parámetros dependientes de la hemoglobina y del recuento de plaquetas. En el análisis por etnicidad, se observaron diferencias significativas en el recuento de glóbulos rojos, hemoglobina y hematocrito (p<0,0001).

Conclusiones

Este estudio demuestra que los intervalos de referencia hematológicos varían según el sexo y la etnicidad, lo cual debería ser considerado en una población multiétnica. Este hallazgo contribuye a un mejor conocimiento de las características individuales de cada persona, facilitando una interpretación clínica más precisa.

A single dose of cajuína does not improve leukocyte count, lipid peroxidation, and physical performance in runners: a randomized, crossover, double‑blind, placebo study

PURPOSE

To investigate the effects of a single dose of cajuína juice physical performance, leukocyte counts, and oxidative stress markers following a 10-km time trial in male runners.

METHODS

A total of nine recreationally trained male runners (32 ± 9.2 years; 70.9 ± 8.1 kg, 1.71 ± 0.06 m, 3.9 ± 1.9 training sessions per week) were randomly assigned to receive either cajuína juice (containing approximately one gram of vitamin C) or a placebo (a similar drink containing 0 mg of vitamin C) two hours before exercise, with a one-week washout period between interventions. Blood samples were collected immediately before ingestion and post-exercise. Leukocyte counts, as well as malondialdehyde (MDA), uric acid, and albumin concentrations, were analyzed from the samples.

RESULTS

Physical performance was not affected by cajuína intake (p > 0.05). Although a time effect (p = 0.01) was observed for MDA concentrations, no condition (p = 0.47) or interaction effects (p = 0.84) were revealed. Additionally, there were no effects of condition, time, and interaction for albumin (p = 0.83, p = 0.37, and p = 0.16, respectively) and uric acid (p = 0.64, p = 0.19, and p = 0.55, respectively) concentrations. No significant or positive changes in leukocyte counts were observed (p > 0.05).

CONCLUSION

The single-dose intake of cajuína (Anacardium occidentale L.) does not improve leukocyte count, lipid peroxidation, or physical performance in recreationally trained male runners subjected to a 10-km time trial.

TRIAL REGISTRATION

The study was registered in the Brazilian Clinical Trials Registry (REBEC) under the following registration number: RBR-3cb6qtz. The study was prospectively registered on November 17, 2023.

Long-Term Environmental Methylmercury Exposure Is Associated with Peripheral Neuropathy and Cognitive Impairment among an Amazon Indigenous Population

Widespread contamination of the Amazon basin with mercury has been reported to occur since at least the mid-80s due to heavy gold mining activity. Although initial studies have indicated that this may lead to deleterious neurological consequences to the indigenous populations living in the region, further research is needed to better characterize the neurological burden of such long-term exposure. With this aim, a cross-sectional exploratory study has been conducted with the Yanomami indigenous population residing in a northern Amazon region. All participants underwent a structured interview; detailed neurological examination, including assessment for cognitive, motor, coordination, and sensory functions; and laboratorial testing for serum hemoglobin, blood glucose, and methylmercury levels in hair samples. This study enrolled 154 individuals of 30.9 ± 16.8 years of age, of which 56.1% were female. Mean methylmercury levels in hair were 3.9 ± 1.7 µg/g. Methylmercury levels in hair > 6.0 µg/g were found in 10.3%. Among participants with hair methylmercury levels ≥ 6.0 μg/g, the prevalences of peripheral neuropathy and reduced cognitive performance were, respectively, 78.8% (95%CI 15-177%, p = 0.010) and 95.9% (95%CI 16-230.8%, p = 0.012) higher than those of individuals with lower levels. These results suggest that chronic mercury exposure may lead to significant and potentially irreversible neurotoxicity to Yanomami population living in the northern Amazon basin.

Before Direct-Acting Antivirals for Hepatitis C Virus: Evaluation of Core Protein R70Q and L/C91M Substitutions in Chronically Infected Brazilian Patients Unresponsive to IFN and/or RBV

Although chronic hepatitis C has been effectively treated with direct-acting antivirals (DAAs), the use of conventional therapy with peg-interferon (Peg-IFN) or (predominantly) ribavirin (RBV), remains widespread. R70Q/H and L/C91M amino acid substitutions in the hepatitis C virus (HCV) core protein may modulate responses to IFN and/or RBV, and are associated with cirrhosis, hepatocellular carcinoma (HCC), insulin resistance, and liver steatosis. We evaluated the R70Q/H and L/C91M substitutions, clinical and epidemiological profiles, and risk factors of Brazilian patients chronically infected with HCV subgenotypes 1a and 1b (HCV-GT1a and HCV-GT1b) unresponsive to IFN and/or RBV therapy. Sequencing and pyrosequencing analyses and sociodemographic and clinical predictive variables were used to assess the relationship between R70Q/H and L/C91M substitutions. Leukocyte counts, ALT levels, and ALT/AST ratios were significantly reduced in treated individuals, but more of these patients had advanced fibrosis and cirrhosis. L91M was more prevalent (19.7%), occurring only in HCV-GT1b, followed by R70Q/P (11.5%) and R70P (1.4%). R70Q/P exhibited higher mean AST, ALT, and GGT values, whereas L91M showed higher mean GGT values. Pyrosequencing of the L91M position revealed mutant subpopulations in 43.75% of samples.

Changes in renal function increase the need for advanced ventilatory support and increase the risk of mortality in critically ill patients with COVID-19

In addition to respiratory failure, another important outcome presented by patients hospitalized with coronavirus disease 2019 (COVID-19) is renal failure, which is related to increased severity of infection and a greater risk of mortality. Severity is often represented by the need for respiratory and/or life support, which can range from oxygen therapy to invasive mechanical ventilation. This study aimed to determine the association between the degree of renal and inflammatory impairment in patients with the need for advanced respiratory support and mortality. Included in the present study were 79 critically ill patients with COVID-19 on different days, who required a nasal cannula and/or orotracheal intubation. Data from laboratory tests, arterial blood gases and information on their clinical evolution were collected. The results obtained showed that the biochemical markers of renal function, as well as the inflammatory markers and the partial pressure of carbon dioxide, were significantly increased in patients who succumbed to the infection. Similarly, these markers were higher amongst patients who required increased respiratory assistance.

Mercury Exposure in Munduruku Indigenous Communities from Brazilian Amazon: Methodological Background and an Overview of the Principal Results

The Amazonian indigenous peoples depend on natural resources to live, but human activities' growing impacts threaten their health and livelihoods. Our objectives were to present the principal results of an integrated and multidisciplinary analysis of the health parameters and assess the mercury (Hg) exposure levels in indigenous populations in the Brazilian Amazon. We carried out a cross-sectional study based on a census of three Munduruku indigenous villages (Sawré Muybu, Poxo Muybu, and Sawré Aboy), located in the Sawré Muybu Indigenous Land, between 29 October and 9 November 2019. The investigation included: (i) sociodemographic characterization of the participants; (ii) health assessment; (iii) genetic polymorphism analysis; (iv) hair mercury determination; and (v) fish mercury determination. We used the logistic regression model with conditional Prevalence Ratio (PR), with the respective 95% confidence intervals (CI95%) to explore factors associated with mercury exposure levels ≥6.0 µg/g. A total of 200 participants were interviewed. Mercury levels (197 hair samples) ranged from 1.4 to 23.9 μg/g, with significant differences between the villages (Kruskal-Wallis test: 19.9; p-value < 0.001). On average, the general prevalence of Hg exposure ≥ 6.0 µg/g was 57.9%. For participants ≥12 years old, the Hg exposure ≥6.0 µg/g showed associated with no regular income (PR: 1.3; CI95%: 1.0-1.8), high blood pressure (PR: 1.6; CI95%: 1.3-2.1) and was more prominent in Sawré Aboy village (PR: 1.8; CI95%: 1.3-2.3). For women of childbearing age, the Hg exposure ≥6.0 µg/g was associated with high blood pressure (PR: 1.9; CI95%: 1.2-2.3), with pregnancy (PR: 1.5; CI95%: 1.0-2.1) and was more prominent among residents in Poxo Muybu (PR: 1.9; CI95%: 1.0-3.4) and Sawré Aboy (PR: 2.5; CI95%: 1.4-4.4) villages. Our findings suggest that chronic mercury exposure causes harmful effects to the studied indigenous communities, especially considering vulnerable groups of the population, such as women of childbearing age. Lastly, we propose to stop the illegal mining in these areas and develop a risk management plan that aims to ensure the health, livelihoods, and human rights of the indigenous people from Amazon Basin.

Previous History of American Tegumentary Leishmaniasis Alters Susceptibility and Immune Response Against Schistosoma mansoni Infection in Humans

Schistosomiasis and Leishmaniasis are chronic parasitic diseases with high prevalence in some tropical regions and, due to their wide distribution, a risk of co-infections is present in some areas. Nevertheless, the impact of this interaction on human populations is still poorly understood. Thus, the current study evaluated the effect of previous American Tegumentary Leishmaniasis (ATL) on the susceptibility and immune response to Schistosoma mansoni infection in residents from a rural community in Northern of Minas Gerais state, Brazil, an area endemic for both parasitic infections. The participants answered a socioeconomic questionnaire and provided stool and blood samples for parasitological and immunological evaluations. Stool samples were examined by a combination of parasitological techniques to identify helminth infections, especially S. mansoni eggs. Blood samples were used for hemograms and to measure the serum levels of cytokines and chemokines. Reports on previous ATL were obtained through interviews, clinical evaluation forms, and medical records. S. mansoni infection was the most prevalent parasitic infection in the study population (46%), and the majority of the infected individuals had a very low parasite burden. In the same population, 93 individuals (36.2%) reported previous ATL, and the prevalence of S. mansoni infection among these individuals was significantly higher than among individuals with no ATL history. A multiple logistic regression model revealed that S. mansoni infection was positively associated with higher levels of CCL3 and CCL17, and a higher frequency of IL-17 responders. Moreover, this model demonstrated that individuals with an ATL history had a 2-fold higher probability to be infected with S. mansoni (OR = 2.0; 95% CI 1.04–3.68). Among S. mansoni-infected individuals, the logistic regression demonstrated that a previous ATL history was negatively associated with the frequency of IL-17 responders and CXCL10 higher responders, but positively associated with higher IL-27 responders. Altogether, our data suggest that previous ATL may alter the susceptibility and the immune response in S. mansoni-infected individuals, which may likely affect the outcome of schistosomiasis and the severity of the disease in humans.

Detection of Common Deletional of α-Thalassemia 3.7 Kb from Metropolitan Region of Manaus, Amazonas, Brazil

Background

Alpha Thalassemia (α-thal) is a heterogeneous group of hereditary alterations caused by deletions that affect alpha regulatory genes, and the 3.7Kb deletion is the most frequent worldwide. The prevalence ranges from 20% and 35% in Brazil, depending mainly on race, predominant in Afro-descendants.

Purpose

The aim was to determine α-thal -^α3.7Kb and -^α4.2Kb deletions, estimating their frequency in individuals from six regions of Amazonas State.

Methods

Volunteers age between 18-59 years old of both genders participated in the study. Blood was collected from March 2014 to September 2017 at the health centers of each participant city. α-thal^3.7Kb was performed by GAP-PCR, while α-thal^4.2Kb by Multiplex-PCR. The total samples collected from each city were: Manaus (capital), 356 (19.7%); Iranduba 232 (12.8%); Manacapuru, 287 (15.9%); Presidente Figueiredo, 370 (20.5%); Itacoatiara, 301 (16.6%); and Coari, 263 (14.5%).

Results

The average age among males was 35.3±14.8, while for females, it was 36.7±14.9 years old. Microcytosis (MCV <80fL) was found in 158 individuals (8,46%) and α-thal diagnosed in 143 individuals (7.9%), and all of these individuals carried the ^3.7Kb deletion 5.95% in heterozygous and 1.95% in homozygous. α-thal^4.2kb was not found in any volunteer. The association analyses to the α-thal^3.7kb genotypes were statistically significant for all hematological parameters (p<.001), except serum iron and serum ferritin analyses.

Conclusion

This study highlights α-thal 3.7kb deletion as an important public health problem, especially in a population not yet characterized about this disease. Thus, epidemiological studies using molecular tools become relevant in regions where the disease is underestimated, contributing to a better understanding of thalassemia incidence and iron deficiency anemias incidence of the participating cities. We reinforce that future molecular studies in North Region from Brazil can be utilized to describe other genetic anemias as structural hemoglobinopathies that have already proven to be highly prevalent in Brazil.

Review of full blood count reference interval using a large cohort of first-time plasmapheresis blood donors

Full blood counts (FBC) are routinely performed on blood donors donating by apheresis. Australian Red Cross Lifeblood (Lifeblood) historically set FBC reference intervals (RIs) in alignment with standards of the Royal College of Pathologists of Australasia (RCPA). Recommendations now advise that RIs be developed locally to represent the population. This study analysed new blood donors' FBC results to inform a review of the current Lifeblood RIs. Retrospective analysis of routine laboratory data for first-time direct to plasmapheresis donations from 1 July 2018 to 30 June 2019 was conducted (n=15,710). FBC were performed using DxH 800 Haematology analysers. The 2.5% and 97.5% percentiles were compared with the current RIs and clinically significant variation informed adjustment. White blood cell and platelet parameters remained in alignment with RCPA reference intervals. The haemoglobin (Hb) RI for female donors reduced from 115-165 g/L to 113-147 g/L. For male donors, the upper limit for Hb required reduction from 185 g/L to 165 g/L. Red blood cell (RBC) counts and haematocrit (HCT) levels were lowered in this derivation from blood donors. Appropriate RIs allow for both the early detection of disease and avoid unnecessary investigation of otherwise healthy people. FBC analysis from current blood donors indicated changes were required to the RIs. The adjusted lower RBC and HCT values reduces the proportion of donors considered to have abnormal findings. The lower Hb limits will remain at 115 g/L in females and 125 g/L in males to align with regulatory requirements for blood donation.