Association between vitamin D deficiency and tuberculosis in a Korean population

Association of variant vitamin statuses and tuberculosis development: a systematic review and meta-analysis

BACKGROUND

Several studies have suggested an association between vitamin deficiency and the development of tuberculosis; however, the precise impact remains unclear. This study aimed to elucidate the relationship between distinct vitamin statuses and the occurrence of tuberculosis.

MATERIALS AND METHODS

Retrieval was conducted using several databases without language restrictions to capture the eligible studies on tuberculosis and vitamin status. Pooled odds ratios (ORs), relative risks (RRs), and hazard ratios (HRs) were used with 95% confidence intervals (CIs) to clarify the relationship between the different vitamin statuses (A, B, D, and E) and the occurrence of tuberculosis. Subgroup analysis, sensitivity analysis, meta-regression analysis, and Galbraith plot were performed to determine sources of heterogeneity. Potential publication biases were detected using Begg's test, Egger's test, and the trim-and-fill test.

RESULTS

We identified 10,266 original records from our database searches, and 69 eligible studies were considered in this study. The random-effect model showed that people with tuberculosis may exhibit vitamin A deficiency (OR = 10.66, 95%CI: 2.61-43.63, p = .001), while limited cohort studies showed that vitamin A supplementation may reduce tuberculosis occurrence. Additionally, vitamin D deficiency was identified as a risk factor for tuberculosis development (RR = 1.69, 95%CI: 1.06-2.67, p = .026), and people with tuberculosis generally had lower vitamin D levels (OR = 2.19, 95%CI: 1.76-2.73, p < .001) compared to other groups. No publication bias was detected.

CONCLUSIONS

This meta-analysis indicated that people with tuberculosis exhibited low levels of vitamins A and D, while vitamin D deficiency was identified as a risk factor for tuberculosis. More randomized controlled interventions at the community levels should be recommended to determine the association between specific vitamin supplementation and tuberculosis onset.

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.

Exploring and exploiting the host cell autophagy during Mycobacterium tuberculosis infection

Tuberculosis, caused by Mycobacterium tuberculosis, is a fatal infectious disease that prevails to be the second leading cause of death from a single infectious agent despite the availability of multiple drugs for treatment. The current treatment regimen involves the combination of several drugs for 6 months that remain ineffective in completely eradicating the infection because of several drawbacks, such as the long duration of treatment and the side effects of drugs causing non-adherence of patients to the treatment regimen. Autophagy is an intracellular degradative process that eliminates pathogens at the early stages of infection. Mycobacterium tuberculosis's unique autophagy-blocking capability makes it challenging to eliminate compared to usual pathogens. The present review discusses recent advances in autophagy-inhibiting factors and mechanisms that could be exploited to identify autophagy-inducing chemotherapeutics that could be used as adjunctive therapy with the existing first-line anti-TB agent to shorten the duration of therapy and enhance cure rates from multidrug-resistant tuberculosis (MDR-TB) and extreme drug-resistant tuberculosis (XDR-TB).

Estimating the tuberculosis incidence using a SARIMAX-NNARX hybrid model by integrating meteorological factors in Qinghai Province, China

Tuberculosis (TB) is recognized as being a major public health concern owing to its increase in Qinghai, China. In this study, we aimed to estimate the long-term effects of meteorological variables on TB incidence and construct an advanced hybrid model with seasonal autoregressive integrated moving average (SARIMA) and a neural network nonlinear autoregression (SARIMAX-NNARX) by integrating meteorological factors and evaluating the model fitting and prediction effect. During 2005-2017, TB experienced an upward trend with obvious periodic and seasonal characteristics, peaking in spring and winter. The results showed that TB incidence was positively correlated with average relative humidity (ARH) with a 2-month lag (β = 1.889, p = 0.003), but negatively correlated with average atmospheric pressure (AAP) with a 1-month lag (β =  - 1.633, p = 0.012), average temperature (AT) with a 2-month lag (β =  - 0.093, p = 0.027), and average wind speed (AWS) with a 0-month lag (β =  - 13.221, p = 0.033), respectively. The SARIMA (3,1,0)(1,1,1)_12, SARIMAX(3,1,0)(1,1,1)₁₂, and SARIMAX(3,1,0)(1,1,1)₁₂-NNARX(15,3) were considered preferred models based on the evaluation criteria. Of them, the SARIMAX-NNARX technique had smaller error values than the SARIMA and SARIMAX models in both fitting and forecasting aspects. The sensitivity analysis also revealed the robustness of the mixture forecasting model. Therefore, the SARIMAX-NNARX model by integrating meteorological variables can be used as an accurate method for forecasting the epidemic trends which would be great importance for TB prevention and control in the coming periods in Qinghai.

Vitamin D deficiency in dengue fever patients' coinfected with H. pylori in Pakistan. A case-control study

Introduction

Dengue fever is a vector-borne disease with an estimate of 390 million persons getting the infection each year with a significant public health impact. It has been reported DENV patients with vitamin D deficiency led to severe form of dengue infection; while H. pylori coinfection alters vitamin D receptors leading to vitamin D deficiency. We hypothesize that DENV patient's having low vitamin D along with H. pylori coinfection could have worsen dengue severity as well as vitamin D deficiency. In this case-control study, we compared (I) the vitamin D deficiency in dengue fever cases with or without H. pylori coinfection, and (II) negative dengue fever as a control with or without H. pylori coinfection. We have also assessed the correlation between vitamin D levels and its effect on warning signs of the dengue fever. Further, we have investigated whether coinfection with H. pylori has any effect on warning signs in the dengue fever patients and the vitamin D deficiency in all serotypes of the dengue virus infected patients.

Methods

In this case control study the association of the vitamin D levels with age, gender and H. pylori coinfection in dengue fever hospitalized patients was assessed using chi-square and multivariate logistic regression analysis.

Results

Four hundred dengue fever patients with H. pylori coinfection were compared with 400 dengue negative controls with H. pylori coinfection. The mean age was 29.96 ± 10.5 and 29.88 ± 10.7 years among cases and controls, respectively. Most dengue fever patients with H. pylori coinfection were deficient in vitamin D compared with negative dengue controls with H. pylori coinfection. In multivariate logistic regression, the dengue cases with H. pylori coinfection were.056 times (95% CI: 0.024, 0.128, P = 0.000) more likely to have vitamin D "deficiency', while compared with the cases who did not have H. pylori coinfection.

Conclusion

The present study proposes that vitamin D deficiency in dengue fever patients coinfected with H. pylori is much higher than the dengue fever negative controls coinfected with H. pylori. As hypothesized the DENV patient with H. pylori coinfection has vitamin D deficiency as well as increased dengue severity.

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.

It Takes a Village: The Multifaceted Immune Response to Mycobacterium tuberculosis Infection and Vaccine-Induced Immunity

Despite co-evolving with humans for centuries and being intensely studied for decades, the immune correlates of protection against Mycobacterium tuberculosis (Mtb) have yet to be fully defined. This lapse in understanding is a major lag in the pipeline for evaluating and advancing efficacious vaccine candidates. While CD4+ T helper 1 (TH1) pro-inflammatory responses have a significant role in controlling Mtb infection, the historically narrow focus on this cell population may have eclipsed the characterization of other requisite arms of the immune system. Over the last decade, the tuberculosis (TB) research community has intentionally and intensely increased the breadth of investigation of other immune players. Here, we review mechanistic preclinical studies as well as clinical anecdotes that suggest the degree to which different cell types, such as NK cells, CD8+ T cells, γ δ T cells, and B cells, influence infection or disease prevention. Additionally, we categorically outline the observed role each major cell type plays in vaccine-induced immunity, including Mycobacterium bovis bacillus Calmette-Guérin (BCG). Novel vaccine candidates advancing through either the preclinical or clinical pipeline leverage different platforms (e.g., protein + adjuvant, vector-based, nucleic acid-based) to purposefully elicit complex immune responses, and we review those design rationales and results to date. The better we as a community understand the essential composition, magnitude, timing, and trafficking of immune responses against Mtb, the closer we are to reducing the severe disease burden and toll on human health inflicted by TB globally.

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.

The Relationship Between Vitamin D and Infections Including COVID-19: Any Hopes?

Vitamin D is proposed to have a potential role in the pathogenicity, clinical presentation, prognosis, complications, and treatment of several diseases. In addition to its well-known role in calcium metabolism, vitamin D regulates both innate and adaptive immunity, and subsequently modulates the antiviral and antibacterial inflammatory immune responses. In view of the emerging coronavirus disease 2019 (COVID-19) pandemic, searching for potential therapeutic and protective strategies is of urgent interest, and vitamin D is one of the promising agents in this field. In this review, we present data from literature that supports the promising role of vitamin D in treatment and/or prevention of several infections including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This review summarizes vitamin D metabolism and its role in inflammation, thrombosis and immune regulation. It also reviews, in short, the role of vitamin D and the impact of its deficiency in several infections namely tuberculosis, influenza, human immunodeficiency virus (HIV), and SARS-CoV-2. Considering the roles of vitamin D on immune modulation, controlling of thrombosis, and attacking several microorganisms, the current review will elaborate on the association between these salient roles of vitamin D and the pathogenicity of various infectious agents including COVID-19. Consequently, the comprehensive finding of the current review shows a possible significant impact of vitamin D supplement as a hope in preventing, treating, and/or improving the progression of certain infections, specifically during the worldwide attempts to fight against the COVID-19 pandemic and minimize the severity of health complications encountered accordingly. In addition, avoiding a status of vitamin D deficiency to obtain its positive effects on the immune system and its protective mechanism during infections will be a general benefit overall.

Oxaliplatin-associated sarcoid-like reaction masquerading as recurrent colon cancer

A 54-year-old man with stage IV B metastatic colorectal cancer with liver and peritoneal metastasis was treated with cytoreductive surgery (extended left colectomy, right partial hepatectomy, resection of right diaphragm nodule) and perioperative oxaliplatin-based chemotherapy. The patient was cancer-free for 6 months, at which point a surveillance positron emission tomography-CT scan showed metabolically active hepatosplenic lesions and mediastinal and bilateral hilar lymph nodes. An endobronchial ultrasound bronchoscopy-guided fine needle aspiration of the mediastinal and hilar lymph nodes revealed non-necrotising granulomas. The workup was negative for bacterial, fungal or mycobacterial infection, cancer or autoimmune disease. Carcinoembryonic antigen and COLVERA (a circulating tumour DNA liquid biopsy test for the detection of recurrent colon cancer) tests were negative. Subsequently the rare diagnosis of a sarcoidosis-like reaction from oxaliplatin-based chemotherapy was made. Repeat imaging after 3 months showed resolution of the hepatosplenic lesions and lymphadenopathy, alike.

Association of vitamin D levels and risk of latent tuberculosis in the hemodialysis population

BACKGROUND

Vitamin D is essential in the host defense against tuberculosis (TB). Suboptimal vitamin D status is common in the hemodialysis population. Hemodialysis patients have an increased risk compared to the general population latent tuberculosis infection (LTBI). However, the association between vitamin D deficiency and LTBI in this population remains unclear.

MATERIALS AND METHODS

We conducted a cross-sectional study between March and May 2017. Interferon-gamma release assay (IGRA) through QuantiFERON-TB Gold In-Tube was used to assess LTBI. Plasma 25-hydroxycholecalciferol (25-OHD) levels were measured by Elecsys Vitamin D Total assay. Suboptimal vitamin D levels included vitamin D insufficiency 20-29 ng/mg and vitamin D deficiency <20 ng/mL. Predictors for LTBI were analyzed.

RESULTS

A total of 287 participants were enrolled. The suboptimal vitamin D level was 31.4% (90/287), which including the vitamin D deficiency was 13.9% (40/287). A total of 49.1% (141/287) people received nutritional vitamin D supplementation. The prevalence of IGRA positivity in this study was 25.1% (72/287). There was no significant difference in vitamin D concentrations or the proportion of vitamin D supplementation among the IGRA-positive and IGRA-negative groups (p = 0.789 and 0.496, respectively). In multivariate analysis, age >65 years old (odds ratio (OR), 1.89; 95% CI, 1.08-3.31; p = 0.026) and TB history (OR, 3.51; 95% CI, 1.38-8.91; p = 0.008) were independent predictors of IGRA positivity.

CONCLUSION

This is the first study to report that vitamin D deficiency was not associated with IGRA positivity in a hemodialysis population. Aging and TB history were both independent predictors for LTBI.

Spatial distribution of tuberculosis and its association with meteorological factors in mainland China

BACKGROUND

The incidence of tuberculosis (TB) remains high worldwide. Current strategies will not eradicate TB by 2035; instead, by 2182 is more likely. Therefore, it is urgent that new risk factors be identified.

METHODS

An ecological study was conducted in 340 prefectures in China from 2005 to 2015. The spatial distribution of TB incidence was shown by clustering and hotspot analysis. The relationship between the distribution patterns and six meteorological factors was evaluated by the geographically weighted regression (GWR) model.

RESULTS

During the 11 years of the study period, TB incidence was persistently low in the east and high in the west. Local coefficients from the GWR model showed a positive correlation between TB incidence and yearly average rainfall (AR) but a negative correlation with other meteorological factors. Average relative humidity (ARH) was negatively correlated with the incidence of TB in all prefectures (p < 0.05).

CONCLUSION

Meteorological factors may play an important role in the prevention and control of TB.

Levels of vitamin D-associated cytokines distinguish between active and latent tuberculosis following a tuberculosis outbreak

BACKGROUND

Vitamin D levels are associated with the extent of mycobactericidal activity. Interleukin (IL)-15 and IL-32 play roles in the vitamin D-mediated tuberculosis (TB) defense mechanism. Vitamin D induces IL-1β, which plays an important role in terms of resistance to TB. We evaluated whether the levels of vitamin D-related cytokines distinguished between those with active TB and latent TB infection (LTBI).

METHODS

In total, 50 TB-infected patients (25 with active TB and 25 with LTBI following a TB outbreak in a high school) were enrolled. Plasma 25-hydroxyvitamin D (25[OH]D), IL-15, IL-32, and IL-1β levels were measured via enzyme-linked immunosorbent assays. Mycobacterium tuberculosis-specific antigen-induced and unstimulated cytokine levels were measured in the supernatants of the QuantiFERON TB Gold-In-Tube (QFT-GIT) assay.

RESULTS

Plasma 25(OH)D and plasma IL-15 levels were lower in patients with active TB than in LTBI subjects (25(OH)D: 16.64 ng/mL vs. 21.6 ng/mL, P = 0.031; IL-15: 148.9 pg/mL vs. 189.8 pg/mL, P = 0.013). Plasma 25(OH)D levels correlated with the plasma levels of IL-15 and IL-1β in TB-infected patients. In addition, the plasma 25(OH)D levels correlated positively with the level of unstimulated IL-15 (IL-15nil) and negatively with that of TB antigen-stimulated IL-32 (IL-32TB) in QFT-GIT supernatants. Although the IL-15nil and IL-15TB levels were higher in LTBI subjects than patients with active TB, the IL-32nil and IL-32TB levels were higher in the latter patients. A combination of the IL-15nil and IL-32TB levels accurately predicted 91.3% of active TB patients and latent subjects, with an area under the curve of 0.964.

CONCLUSIONS

Our preliminary data showed that the levels of the vitamin D-related cytokines IL-15 and IL-32 differed between active TB patients and LTBI subjects. This result might be used as a basic data for developing biomarkers distinguishing between active TB and LTBI.

Assessment of Vitamin Status in Patients with Nontuberculous Mycobacterial Pulmonary Disease: Potential Role of Vitamin A as a Risk Factor

As microbiological diagnostic techniques improve and the frequency of nontuberculous mycobacterial pulmonary disease (NTM-PD) infection increases worldwide, NTM-PD is becoming increasingly important to clinicians and researchers. Vitamin activity has been associated with the host immune response in tuberculosis; however, such information is very limited in NTM-PD. We performed a case-control study in 150 patients with NTM-PD and 150 healthy controls to investigate serum vitamin status. We measured concentrations of vitamins A, D, and E along with homocysteine and methylmalonic acid (MMA) as indicators of vitamin B₁₂ deficiency, using high-performance liquid chromatography (HPLC) or HPLC-tandem mass spectrometry. The serum concentrations of vitamins A and E were significantly lower in patients with NTM-PD than in healthy controls (1.5 vs. 2.1 µmol/L, p < 0.01 for vitamin A; and 27.3 vs. 33.1 µmol/L, p < 0.01 for vitamin E). In contrast, the serum concentrations of vitamin D and homocysteine were not significantly different between the two groups. Vitamin A deficiency (< 1.05 µmol/L) was significantly more prevalent in patients with NTM-PD than in healthy controls (p < 0.01) and was associated with an 11-fold increase in risk of NTM-PD. Multiple vitamin deficiencies were only observed in patients with NTM-PD (7.3% of all NTM-PD patients). Positive correlations were observed among vitamins (vitamins A and D; r = 0.200, p < 0.05; vitamins D and E, r = 0.238, p < 0.05; vitamins A and E, r = 0.352, p < 0.05). Serum vitamin status, demographic variables, and biochemical indicators were not associated with treatment outcomes. Vitamin A deficiency was strongly associated with patients with NTM-PD. Our study suggests that altered vitamin status is associated with mycobacterial disease. Future well-designed prospective studies with large patient cohorts addressing these issues are needed to clarify the significance of vitamins in NTM-PD.

Vitamin D in malaria: more hypotheses than clues

Vitamin D is a secosteroid hormone regulating calcium and phosphate metabolism, immune response and brain development. Low blood 25(OH)D levels have been reported in patients affected by infectious diseases caused by parasites, including malaria. Despite the high effectiveness of antimalarials, malaria is burdened with high morbidity and mortality, and the search for additional therapies is rapidly growing. Furthermore, available preventive measures have proved to be barely effective so far. Finding new prevention and therapy tools is a matter of urgency. Studies on animal models and humans have hypothesized some mechanisms by which the hormone can influence malaria pathogenesis, and the role of Vitamin D supplementation in preventing and treating this disease has been suggested. Few studies on the association between Vitamin D and malaria are available and disagreeing results have been reported. Studies in humans reporting an association between low 25(OH)D circulating levels and Malaria have a small sample size and observational study-set. Randomized controlled trials are needed in order to understand if Vitamin D administration might play a role in preventing and treating malaria.

25-Hydroxyvitamin D concentrations in dogs with naturally acquired blastomycosis

Background

Hypovitaminosis D is common in humans with tuberculosis, and adequate serum 25‐hydroxyvitamin D [25(OH)D] concentrations may improve response to therapy. The pathomechanism of Blastomyces dermatitidis is similar to that of Mycobacterium tuberculosis, but the 25(OH)D status of dogs with blastomycosis has not been investigated.

Objectives

To determine if dogs with blastomycosis have lower 25(OH)D concentrations compared with healthy controls and to explore the prognostic value of 25(OH)D concentrations in blastomycosis.

Animals

35 control dogs (16 client‐owned, healthy dogs and 19 healthy, random‐source hound mixes) and 22 dogs with blastomycosis.

Methods

Prospective study. Serum concentrations of 25(OH)D, parathyroid hormone (PTH), ionized calcium were measured, and biochemistry and hematology profiles were performed. The 25‐hydroxyvitamin D concentrations were compared between groups, and factors associated with 25(OH)D variation were investigated in dogs with blastomycosis. Dogs with blastomycosis were followed for up to 5 years after discharge and factors associated with survival were investigated.

Results

Dogs with blastomycosis had significantly lower concentrations of 25(OH)D and PTH and higher concentrations of ionized calcium than did control dogs. In dogs with blastomycosis, 25(OH)D concentrations were independently associated with neutrophil count, pCO₂, and with bone and skin involvement. The 25‐hydroxyvitamin D concentration was not associated with survival in dogs with blastomycosis, whereas lactate concentrations; bone, skin, and lymph node involvement; number of affected sites; and, presence of respiratory signs were associated with survival.

Conclusions and Clinical Importance

Dogs with blastomycosis had lower 25(OH)D concentrations than did healthy controls. Despite no impact on survival, investigating the effect of 25(OH)D supplementation on recovery is warranted.

Vitamin D supplementation as a control program against latent tuberculosis infection in Korean high school students

The prevalence of latnet Mycobacterium tuberculosis infection (LTBI) in the first-grade high school students in South Korea was 2.1%, which was the lowest level at congregated settings in 2017. For LTBI cases refusing anti-tuberculosis (TB) medication or having poor compliance, additional support should be considered. Eight systematic reviews concluded that vitamin D (VD) deficiency is a risk factor for TB. While three of four South Korean adolescents were VD deficiency, VD supplementation could be a practical remedy to protect LTBI students of refusing anti-TB medication or having poor compliance.

Serum vitamin D level and vitamin D receptor genotypes may be associated with tuberculosis clinical characteristics: A case-control study

Vitamin D is associated with the susceptibility of tuberculosis and might have an adjunctive effect on anti-tuberculosis treatment. This study aims to investigate the association of vitamin D deficiency and vitamin D receptor (VDR) gene polymorphisms with susceptibility and severity to multidrug-resistant tuberculosis (MDR-TB) in comparison with drug-sensitive tuberculosis (DS-TB) and health controls in China.A total of 180 patients with pulmonary TB (128 DS-TB, 52 MDR-TB) and 59 healthy controls were enrolled into 3 groups. Vitamin D levels and VDR genotypes at FokI, BsmI, ApaI, and TaqI sites of all the participants and clinical characteristics of patients with TB were measured and collected.Statistical analysis revealed that vitamin D levels were lower in both TB groups. Patients with TB with bilateral lesions and patients with MDR-TB with extrapulmonary TB had lower vitamin D levels. The frequencies of ff genotype and f allele were higher in both TB groups. Patients with Ff genotype and ff genotype had lower proportion of extrapulmonary TB. Patients with ff genotype had higher proportion of retreatment. Male patients with ff genotype had higher proportion of cavity formation. Patients with DS-TB with AA genotype had higher proportion of cavity formation.Our findings demonstrate that vitamin D deficiency and ff genotype may be the risk factors of TB in Chinese population. In addition, patients with TB with lower level of vitamin D may have a greater risk of bilateral lesions and extrapulmonary TB. VDR genotypes may be associated with TB clinical characteristics.

Serum vitamin D levels and risk of prevalent tuberculosis, incident tuberculosis and tuberculin skin test conversion among prisoners

Poor vitamin D status has been associated with tuberculosis (TB); whether poor status is cause or consequence of disease is uncertain. We conducted a case-control study and two nested case-control studies to determine whether vitamin D levels were associated with active TB, tuberculin skin test (TST) conversion, and risk of progression to the active TB in prisoners in Brazil. In multivariable conditional logistic regression, subnormal vitamin D levels (OR, 3.77; 95% CI, 1.04–13.64) were more likely in prisoners with active TB. In contrast, vitamin D was not found to be a risk factor for either TST conversion (OR, 2.49; 95% CI, 0.64–9.66) or progression to active disease (OR, 0.59; 95% CI, 0.13–2.62). Black race (OR, 11.52; 95% CI, 2.01–63.36), less than 4 years of schooling (OR, 2.70; 95% CI, 0.90–8.16), cigarette smoking (OR, 0.23; 95% CI, 0.06–0.79) were identified as risk factors for TST conversion. Risk of progression to active TB was found to be associated with cigarette smoking (OR, 7.42; 95% CI, 1.23–44.70). Our findings in the prison population show that poor vitamin D status is more common in individuals with active TB, but is not a risk factor for acquisition of latent TB or progression to active TB.

Prevalence of diabetes mellitus in newly diagnosed pulmonary tuberculosis in Beira, Mozambique

Introduction

Data regarding the association between diabetes mellitus (DM) and tuberculosis (TB) in Africa are scarce. DM screening among TB patients in Mozambique was carried out.

Methods

The study was implemented from January to August 2016 in three Urban Health Centers in Beira, Mozambique and recruited adult (>18 years) patients newly diagnosed with pulmonary TB.

Results

Three hundred and one patients were enrolled (67.4%, males mean age 31.7(SD 11 years). Diabetes was diagnosed in only 3 patients (1%) and impaired glucose tolerance (IGT) in an additional 6 subjects (2%).

Conclusion

A lower than expected prevalence of DM was observed, which could be explained by the lack of traditional risk factors for DM (overweight, age over 45 years, hypertension and smoking) in Mozambique.

Vitamin D and Infectious Diseases: Simple Bystander or Contributing Factor?

Vitamin D (VD) is a fat-soluble steroid essential for life in higher animals. It is technically a pro-hormone present in few food types and produced endogenously in the skin by a photochemical reaction. In recent decades, several studies have suggested that VD contributes to diverse processes extending far beyond mineral homeostasis. The machinery for VD production and its receptor have been reported in multiple tissues, where they have a pivotal role in modulating the immune system. Similarly, vitamin D deficiency (VDD) has been in the spotlight as a major global public healthcare burden. VDD is highly prevalent throughout different regions of the world, including tropical and subtropical countries. Moreover, VDD may affect host immunity leading to an increased incidence and severity of several infectious diseases. In this review, we discuss new insights on VD physiology as well as the relationship between VD status and various infectious diseases such as tuberculosis, respiratory tract infections, human immunodeficiency virus, fungal infections and sepsis. Finally, we critically review the latest evidence on VD monitoring and supplementation in the setting of infectious diseases.

Vitamin D deficiency is associated with increased risk of bacterial infections after kidney transplantation

BACKGROUND/AIMS

There may be an association between vitamin D levels and allograft outcomes in kidney transplant recipients (KTRs). However, few studies have been conducted to determine the association between vitamin D levels and post-transplant infections. This study investigated the impact of vitamin D deficiency on the risk of infection after kidney transplantation.

METHODS

We measured 25-hydroxyvitamin D (25(OH)D) levels prior to kidney transplantation. Vitamin D deficiency was defined as a serum 25(OH)D level < 20 ng/mL. We examined the incidence of various post-transplant infections during follow-up period. We used Cox proportional hazards regression analysis to determine factors associated with increased risk of post-transplant infections during the follow-up period.

RESULTS

A total of 164 KTRs were followed up for a mean of 24.8 ± 10.7 months. Among them, 135 patients (82.3%) had vitamin D deficiency. Patients with vitamin D deficiency had a significantly higher incidence of urinary tract infection (p = 0.027) and any bacterial infection (p = 0.010) compared to those without vitamin D deficiency. Vitamin D deficiency was not significantly associated with incidence of viral or fungal infections. Cox proportional hazards regression analysis revealed that vitamin D deficiency (hazard ratio, 11.07; 95% confidence interval, 1.46 to 84.03; p = 0.020) was independent risk factor for post-transplant bacterial infections.

CONCLUSIONS

Pre-transplant vitamin D deficiency was a significant risk factor for bacterial infections after kidney transplantation. Further studies are needed on possible benefits of vitamin D supplementation for preventing post-transplant bacterial infection.

Severe hypovitaminosis D in active tuberculosis patients and its predictors

BACKGROUND & AIMS

Tuberculosis (TB) patients have a significant vitamin D deficiency (VDD) endemic, which may be closely related to the onset and progress of the disease. The comorbidity of diabetes (DM) and TB has posed an increasing challenge in recent years. However, the influence of DM on TB and the possible mechanism are still uncertain. We carried out this study to identify the nutritional status of vitamin D (VD) in TB patients in a northern city in China (latitude 36° N) and investigate the possible predictors of severe vitamin D deficiency (SVDD).

METHODS

A cross-sectional study including 461 active TB patients (192 with and 269 without DM) were randomly selected from Qingdao Chest Hospital from June 2015 to August 2016. We measured serum 25 hydroxyvitamin D [25(OH)D], and investigated the association between sociodemographic, dietary intake, DM, body mass index (BMI), severity of initial TB signs and symptoms (TB score) and VD status. Multivariate logistic regression analysis was used to define the possible predictors of SVDD.

RESULTS

The median serum 25(OH)D concentration was 8.50 ng/mL. Of the 461 TB patients included, 383 (83.1%) had VDD [25(OH)D < 20 ng/mL], and 217 (47.1%) had SVDD [25(OH)D < 8 ng/mL]. The variables associated with serum 25(OH)D concentrations were DM, outdoor activity level, TB score and BMI (p < 0.05). Patients with severe TB score had nearly 5 fold higher risk of having SVDD compared with those in mild subgroup [OR (95% CI) = 4.919 (2.644-9.150), p < 0.001]. Low outdoor activity level also increased the odds of SVDD, while DM and high fish consumption showed protect effects.

CONCLUSIONS

Severe hypovitaminosis D is prevalent in active TB patients, and the main predictors of SVDD were severe TB score, low outdoor activity, inadequate fish consumption. Lowered serum 25(OH)D may be associated with increased risk of TB in DM.

Association of high serum vitamin D concentrations with active pulmonary TB in an HIV co-endemic setting, Harare, Zimbabwe

Background

There is paucity data on the association of vitamin D deficiency (VDD) and active tuberculosis (TB) in southern Africa where the human immunodeficiency virus (HIV) is co-endemic. We examined the association of serum vitamin D concentrations with active pulmonary tuberculosis (PTB) in HIV-infected (n = 284) and uninfected (n = 267) Black Zimbabweans, in Harare, Zimbabwe.

Methods

We conducted a cross-sectional study of 551 participants comprising 145 HIV⁺/PTB ⁺, 139 HIV⁺/PTB⁻, 134 HIV⁻/PTB⁺ and 133 HIV⁻/PTB⁻. PTB status was confirmed using sputum by culture, or smear microscopy, or GeneXpert MTB/RIF. Serum 25-hydroxyvitamin D (25(OH)D) concentrations were measured using a competitive chemiluminescent immunoassay prior to commencement of anti-TB treatment.

Results

In all four groups, the median vitamin D concentrations were above the 20 ng/ml cut off for VDD. However, the median vitamin D concentrations in all the four groups were below the cut off for vitamin D sufficiency ≥30 ng/ml. The median vitamin D concentrations were significantly higher in PTB⁺ cases; 24.2 ng/ml (IQR: 18.8–32.0) compared to PTB⁻ controls 20.9 ng/ml (IQR: 17.1–26.9), p < 0.0001 regardless of HIV status. The HIV⁺/PTB⁺ group had the highest median vitamin D concentration (25.3 (IQR: 18.0–33.7 ng/ml) whilst the HIV⁺/PTB⁻ group had the lowest; 20.4 ng/ml (IQR: 14.6–26.9), p = 0.0003. Vitamin D concentration <30 ng/ml was associated with 43% lower odds of being PTB⁺ OR 0.57 (95% CI 0.35–0.89).

Conclusions

Our results are not in agreement with the generally accepted hypothesis that VDD is associated with active PTB. To the contrary our results showed an association of higher vitamin D concentrations with active TB irrespective of HIV status. Although findings from the available pool of case control studies remain inconsistent, the results from the current study provide further rationale for larger-scale, prospectively designed studies to evaluate whether sufficient vitamin D concentrations do indeed precede the development of active PTB in our setting.

Recommendations for Optimizing Tuberculosis Treatment: Therapeutic Drug Monitoring, Pharmacogenetics, and Nutritional Status Considerations

Although tuberculosis is largely a curable disease, it remains a major cause of morbidity and mortality worldwide. Although the standard 6-month treatment regimen is highly effective for drug-susceptible tuberculosis, the use of multiple drugs over long periods of time can cause frequent adverse drug reactions. In addition, some patients with drug-susceptible tuberculosis do not respond adequately to treatment and develop treatment failure and drug resistance. Response to tuberculosis treatment could be affected by multiple factors associated with the host-pathogen interaction including genetic factors and the nutritional status of the host. These factors should be considered for effective tuberculosis control. Therefore, therapeutic drug monitoring (TDM), which is individualized drug dosing guided by serum drug concentrations during treatment, and pharmacogenetics-based personalized dosing guidelines of anti-tuberculosis drugs could reduce the incidence of adverse drug reactions and increase the likelihood of successful treatment outcomes. Moreover, assessment and management of comorbid conditions including nutritional status could improve anti-tuberculosis treatment response.

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

BACKGROUND AND AIM

To conduct meta-analyses of all published studies on various aspects of association between vitamin D and tuberculosis (TB).

METHODS

PubMed and Web of Knowledge were searched for all properly controlled studies on vitamin D and TB. Pooled odds ratio, mean difference or standardized mean difference, and its corresponding 95% confidence interval were calculated with the Cochrane Review Manager 5.3.

RESULTS

A significantly lower vitamin D level was found in TB patients vs controls; vitamin D deficiency (VDD) was associated with an increased risk of TB, although such an association was lacking in the African population and in the human immunodeficiency virus-infected African population. A significantly lower vitamin D level was found in human immunodeficiency virus-TB-coinfected African patients receiving antiretroviral treatment who developed TB-associated immune reconstitution inflammatory syndrome vs those who did not develop TB-associated immune reconstitution inflammatory syndrome. VDD was associated with an increased risk of developing active TB in those subjects with latent TB infection and with an increased risk of tuberculin skin test conversion/TB infection conversion, and the trend toward a lower vitamin D level in active TB patients vs latent TB infection subjects did not reach statistical significance, indicating that VDD was more likely a risk factor than a consequence of TB. This concept was further strengthened by our result that anti-TB treatment did not affect vitamin D level in TB patients receiving the treatment.

CONCLUSION

Our analyses revealed an association between vitamin D and TB. VDD is more likely a risk factor for TB than its consequence. More studies are needed to determine whether vitamin D supplementation is beneficial to TB prevention and treatment.

Evaluation of vitamin status in patients with pulmonary tuberculosis

OBJECTIVE

Vitamins are known to be associated with immunity and nutrition. Moreover, vitamin deficiency can affect host immunity to various infectious diseases, including tuberculosis. Although patients with tuberculosis often have vitamin D deficiency, little is known about the levels of other vitamins. Here, we aimed to investigate the status of vitamins A, B₁₂, D, and E in patients with tuberculosis. We also aimed to investigate the clinical and laboratory variables related to vitamin status in patients with tuberculosis.

METHODS

We performed a case-control study to investigate the serum vitamin concentrations in 152 patients with tuberculosis and 137 control subjects. The concentrations of vitamin A, vitamin D, vitamin E, homocysteine, and methylmalonic acid were measured using high-performance liquid chromatography (HPLC) or HPLC-tandem mass spectrometry. Patient demographic data and other biochemical parameters were also analyzed.

RESULTS

The serum concentrations of vitamins A, D, and E were significantly lower in patients with tuberculosis than in control subjects (1.4 vs. 2.0 μmol/L, P < 0.001; 10.6 vs. 19.3 ng/mL, P < 0.001; and 22.8 vs. 30.6 μmol/L, P < 0.001, respectively). In contrast, the methylmalonic acid levels were higher in patients with tuberculosis (134.9 vs. 110.8 nmol/L, P < 0.001). The prevalences of vitamin deficiencies were significantly higher in patients with tuberculosis. Moreover, multiple vitamin deficiencies were only observed in patients with tuberculosis (22.4% of all patients with tuberculosis vs. 0% of all control subjects). Positive correlations among vitamin A, D, and E concentrations were observed (vitamins A and D, r = 0.395; vitamins D and E, r = 0.342; and vitamins A and E, r = 0.427, P < 0.001). Body mass index, total cholesterol, low-density lipoprotein, iron, and total iron-binding capacity all showed positive correlations with vitamin A, D, and E concentrations.

CONCLUSIONS

Vitamin deficiencies are common in patients with tuberculosis. Further research investigating the clinical importance of vitamin and nutritional status in patients with tuberculosis is needed.

Tuberculosis and diabetes: current state and future perspectives

This review outlines the association between tuberculosis and diabetes, focusing on epidemiology, physiopathology, clinical aspects, diagnosis and treatment, and evaluates future perspectives, with particular attention to developing countries.

Frequency of hypovitaminosis D and its associated risk factors in newly diagnosed pulmonary tuberculosis patients

Objective:

To find out the frequency of hypovitaminosis D and its associated risk factors in newly diagnosed pulmonary tuberculosis patients prior to administration of standard anti tuberculosis therapy.

Methods:

This cross-sectional study was carried out in Ojha Institute of Chest Diseases-DUHS. After approval from BASR and following written informed consent eighty newly diagnosed, as per WHO criteria, tuberculosis patients were enrolled. Prior to the initiation of anti tuberculosis therapy, the serum vitamin D level was determined by 25-OH Vitamin D kit using the chemiluminescent immunoassay (CLIA) method. A cut off value of >30 ng/mL of serum vitamin D was taken as normal whereas a range between 10-30 ng/mL and <10 ng/mL were considered insufficient and deficient respectively. Frequency of socio-demographic associated risk factors of hypovitaminosis D was also determined.

Results:

Out of eighty newly diagnosed tuberculosis patients 33 (41.25%) were males and 47(58.75%) were females with their ages ranging from 18-50 years. 54 patients (26 male and 28 female patients) were smokers. BMI of all the patients was found to be less than the normal ranges. Hypovitaminosis was present in all the cases. Vitamin D insufficiency was found in 49 participants (20 male and 29 female) whereas 31 patients (13 male and 18 female) were found to be vitamin D deficient.

Conclusion:

Prevalence of serum vitamin D level derangement is very high in newly diagnosed patients with pulmonary tuberculosis in our local setting which necessitates administration of adjuvant vitamin D along with standard anti tuberculosis therapy.

Elevated serum 25-hydroxy (OH) vitamin D levels are associated with risk of TB progression in Gambian adults

Background

Vitamin D is essential in the host defence against tuberculosis (TB) as an immune modulator. The aim of this study was to determine the level of 25-hydroxyvitamin D (25 (OH) D) from adult TB index cases before and after treatment and their exposed household contacts (HHC) in The Gambia.

Methods

Serum from adult index TB cases and their TB-exposed household contacts (HHC) was analysed for 25(OH) D and Vitamin D binding protein (VDBP) concentrations. Tuberculin skin test (TST) status was used as a measure of Mycobacterium tuberculosis (Mtb) infectivity in the HHC. In addition, HHC who later progressed to active TB (incident cases) were assessed alongside non-progressors to determine the influence of 25 (OH) D levels on TB risk.

Results

Eighty-three TB cases, 46 TST+ and 52 TST− HHC were analysed. Generally levels of 25(OH) D were considered insufficient in all subjects. However, median levels of 25(OH) D and VDBP were significantly higher in TB cases compared to both TST+ and TST− HHC at recruitment and were significantly reduced after TB therapy (p < 0.0001 for all). In addition, levels of serum 25(OH) D at recruitment were significantly higher in TB progressors compared to non-progressors (median (IQR): 25.0(20.8–29.2) in progressors and 20.3 (16.3–24.6) ng/ml in non-progressors; p = 0.007).

Conclusion

In The Gambia, an equatorial country, 25(OH) D levels are higher in serum of TB progressors and those with active disease compared to latently infected and uninfected subjects. These results contrast to findings in non-equatorial countries.

Calcitriol inhibits bleomycin-induced early pulmonary inflammatory response and epithelial-mesenchymal transition in mice

Early pulmonary inflammation and epithelial-mesenchymal transition (EMT) play important roles during lung fibrosis. Increasing evidence demonstrates that calcitriol, the active form of vitamin D3, has anti-inflammatory activities. The aim of this study was to investigate the effects of calcitriol on bleomycin (BLM)-induced early pulmonary inflammation and subsequent EMT. Mice were intratracheally injected with BLM (3.0mg/kg). In three calcitriol+BLM groups, mice were intraperitoneal (i.p.) injected with different doses of calcitriol (0.2, 1.0 or 5.0 μg/kg) daily, beginning at 48 h before BLM injection. Twenty-four hours, seven and fourteen days after BLM injection, pulmonary inflammation and EMT were evaluated. As expected, BLM-induced infiltration of inflammatory cells in the lungs was attenuated by calcitriol. BLM-induced pulmonary inflammatory cytokines were repressed by calcitriol. Moreover, BLM-induced nuclear translocation of nuclear factor kappa B (NF-κB) p65 was blocked by calcitriol. In addition, BLM-induced phosphorylation of pulmonary p38 MAPK and protein kinase B (Akt) was inhibited by calcitriol. Further analysis showed that BLM-induced α-smooth muscle actin (α-SMA), a marker for EMT in the lungs, was significantly attenuated by calcitriol. BLM-induced transforming growth factor-beta 1 (TGF-β1) up-regulation and Smad phosphorylation were attenuated by calcitriol. In conclusion, calcitriol inhibits BLM-induced early pulmonary inflammation and subsequent EMT.

Vitamin D Status in South Korean Military Personnel with Acute Eosinophilic Pneumonia: A Pilot Study

Background

A relationship between low vitamin D levels and the development or outcomes of respiratory diseases has been identified. However, there is no data on the vitamin D status in patients with acute eosinophilic pneumonia (AEP). We evaluated the vitamin D status in patients with AEP among South Korean military personnel.

Methods

We prospectively compared the serum levels of total 25-hydroxyvitamin D [25(OH)D], 25(OH)D3, and 25(OH)D2 among patients with AEP, pulmonary tuberculosis (PTB), and community-acquired pneumonia (CAP).

Results

In total, 65 patients with respiratory diseases, including AEP (n=24), PTB (n=19), and CAP (n=22), were identified. Of the 24 patients with AEP, 2 (8%) had deficient total 25(OH)D levels (<10 ng/mL), 17 (71%) had insufficient total 25(OH)D levels (≥10 to <30 ng/mL), and only 5 (21%) had sufficient total 25(OH)D levels (≥30 to <100 ng/mL). The difference in the total 25(OH)D levels among patients with AEP, PTB, and CAP was not statistically significant (p=0.230). The median levels of total 25(OH)D, 25(OH)D3, and 25(OH)D2 were 22.84, 22.84, and 0.00 ng/mL, respectively, and no differences in the 25(OH)D level were present among patients with AEP, PTB, and CAP with the exception of the total 25(OH)D level between patients with AEP and PTB (p=0.042).

Conclusion

We have shown that low vitamin D levels are frequently found in patients with AEP and are comparable with those in patients with PTB and CAP.

A serum vitamin D level <25nmol/l pose high tuberculosis risk: a meta-analysis

Background

Low serum Vitamin D is considered to be associated with tuberculosis while the “dangerous” level was not clear. The aim of this study was to identify the association between tuberculosis and serum Vitamin D levels via synthesis of available evidence.

Methods

A search of EMBASE, Medline, ISI Web of knowledge, and Pubmed was conducted. The number of subjects of tuberculosis and no-tuberculosis groups in four Vitamin D range. Meta-analyses were performed and presented by odds ratios (ORs) and corresponding 95% confidence intervals (CIs).

Results

A total of 15 studies involving 1440 cases and 2558 controls were included. A significantly increased risk of tuberculosis was found in two ranges: ≤ 12.5 nmol/L: pooled OR = 4.556, 95% CI = 2.200-9.435; 13-25 nmol/L: pooled OR = 3.797, 95% CI = 1.935-7.405. No statistically significant risk of tuberculosis was found in the range of 26–50 nmol/L (pooled OR = 1.561, 95% CI =0.997-2.442). In range 51–75 nmol/L, no positive association was found (pooled OR =1.160, 95% CI = 0.708-1.900).

Conclusions

This study found that a serum Vitamin D level ≤ 25 nmol/L was significantly associated with an increased risk of tuberculosis while the range of 51–75 nmol/L was not. The range 26-50nmol/L posed potential high tuberculosis risk. Future large-scale, well-designed studies are needed to verify these results.

Vitamin D deficiency is an independent risk factor for urinary tract infections after renal transplants

Vitamin D deficiency is frequently found in patients with renal transplants (RTxs). Because vitamin D plays indispensable roles in the immune system, there may be an association between vitamin D deficiency and infection in these patients, but this has not been fully elucidated. Therefore, this study investigated the impact of pre-RTx vitamin D deficiency on urinary tract infection (UTI) development after RTx.We measured 25-hydroxyvitamin D3 (25(OH)D3) levels in 410 patients 2 weeks before they underwent RTx. Vitamin D deficiency was defined as 25(OH)D3 <10 ng/mL. The primary outcome was UTI occurrence after RTx. Cox proportional hazard analysis determined whether vitamin D deficiency was independently associated with UTI.The mean 25(OH)D3 level was 12.8 ± 6.9 ng/mL, and 171 patients (41.7%) were vitamin D deficient. During a median follow-up duration of 7.3 years, the UTI incidence was significantly higher in vitamin D-deficient patients (52 patients, 30.4%) compared with vitamin D-nondeficient patients (40 patients, 16.7%) (P = 0.001). Moreover, multivariate Cox proportional hazard analysis showed that vitamin D deficiency was an independent predictor of UTI after RTx (hazard ratio 1.81, 95% confidence interval 1.11-2.97, P = 0.02).Vitamin D deficiency was an independent risk factor for UTI after RTx; hence, determining 25(OH)D3 levels might help to predict infectious complications after RTx.

Vitamin D Status, Receptor Gene Polymorphisms, and Supplementation on Tuberculosis: A Systematic Review of Case-Control Studies and Randomized Controlled Trials

OBJECTIVE

To investigate the impacts of vitamin D status, supplementation and vitamin D receptor (VDR) gene polymorphisms on tuberculosis (TB).

METHODS

We conducted a systematic review of published studies pertaining to case-control and randomized-control trials from 2002 to 2014 using the PubMed database.

RESULTS AND CONCLUSION

Individuals with TB have lower vitamin D status than healthy individuals. Some VDR gene polymorphisms are associated with increased susceptibility to TB while others may not. Supplementation with vitamin D leads to improved clinical outcomes. However, further studies with a larger patient population and different ethnicities are needed to confirm these effects.

Cell death and autophagy in tuberculosis

Mycobacterium tuberculosis has succeeded in infecting one-third of the human race though inhibition or evasion of innate and adaptive immunity. The pathogen is a facultative intracellular parasite that uses the niche provided by mononuclear phagocytes for its advantage. Complex interactions determine whether the bacillus will or will not be delivered to acidified lysosomes, whether the host phagocyte will survive infection or die, and whether the timing and mode of cell death works to the advantage of the host or the pathogen. Here we discuss cell death and autophagy in TB. These fundamental processes of cell biology feature in all aspects of TB pathogenesis and may be exploited to the treatment or prevention of TB disease.