Association between FokI polymorphism in vitamin D receptor gene and susceptibility to spinal tuberculosis in Chinese Han population

Prevalence of Vitamin D Receptor Gees Polymorphisms in People with Pulmonary Tuberculosis: A Systematic Review and Meta-Analysis

Background

Polymorphisms in the vitamin D receptor (VDR) play an effective role in the susceptibility of pulmonary tuberculosis (TB). Given the importance of this polymorphism and its association with pulmonary TB, this study aimed to investigate the prevalence of VDR polymorphisms in people with pulmonary TB.

Methods

The search process was performed from 2009 to 2023 according to PRISMA (Preferred reporting items for systematic reviews and meta-analyses). The strengthening of the reporting of observational studies in epidemiology (STROBE) checklist was used to qualify the articles. The data was entered into STATA version 14 software, then the fixed effects model and the random effects model, effect size (ES), and Q test (P < 0.10) were used for data analysis at a confidence interval level (CI) of 95%. Two-sided statistical tests were considered with α=0.05.

Results

In this research, 28 articles were analyzed. Polymorphisms showed a significant relationship with susceptibility to pulmonary TB (P = 0.000), and significant heterogeneity (P = 0.000) was seen between polymorphisms. FokI (95% CI: 0.39-0.46, P = 0.000, ES = 43%), ApaI (95% CI: 0.31-0.48, P = 0.000, ES = 39%) and BsmI (95% CI: 0.24-0.50, P = 0.000, ES = 37%) showed the most frequent gene polymorphisms after TaqI (95% CI: 0.34-0.77, P = 0.000, ES = 56%).

Conclusion

ApaI, BsmI, FokI, and TaqI polymorphisms were found in patients suffering from pulmonary TB. Polymorphisms related to the TaqI gene were the most frequent. Controlling and prescribing vitamin D may be needed in these patients.

The Evolution of Diagnostic Techniques in the Paleopathology of Tuberculosis: A Scoping Review

Tuberculosis (TB) is an ancient chronic infectious disease that remains a global health concern. In human remains, the most common and characteristic clinical signs are the skeletal modifications involving the spine, such as in Pott's disease. Diagnosing TB in ancient human remains is challenging. Therefore, in this systematic review, the authors investigated the studies assessing molecular diagnosis of Pott's disease in ancient human remains with the intention to survey the literature, map the evidence, and identify gaps and future perspectives on TB in paleopathology. Our systematic review offers a full contextualization of the history of Pott's disease in ancient times. Our search strategy was performed between August 2022 and March 2023. The authors initially identified 340 records, and 74 studies were finally included and assessed for qualitative analysis. Due to non-specific clinical signs associated with TB, how best to diagnose tuberculosis in human remains still represents a central point. Nevertheless, ancient DNA (aDNA) analysis, lipid biomarkers, and spoligotyping might be extremely useful tools in the study of TB in human remains. Moreover, we propose the extraction and study of immune response genes involved in innate and adaptive immunity versus Mycobacterium spp. as an innovative and vastly overlooked approach in TB paleopathology. Complementary methodologies should be integrated to provide the best approach to the study of TB in human remains.

Pathogenesis, Diagnostic Challenges, and Risk Factors of Pott's Disease

Tuberculosis (TB) prevalence is increasing in developed nations and continuing to cause significant mortality in low- and middle-income countries. As a result of the uptick in cases, there also exists an increased prevalence of extrapulmonary TB. TB is caused by Mycobacterium tuberculosis (M. tb). When M. tb disseminates to the vertebral column, it is called Pott's disease or spinal TB. The frequency, symptoms, and severity of the disease range by the location of the spine and the region of the affected vertebrae. While the current literature shows that timely diagnosis is crucial to reduce the morbidity and mortality from Pott's disease, there is a lack of specific clinical diagnostic criteria for Pott's disease, and the symptoms may be very non-specific. Studies have shown that novel molecular diagnostic methods are effective and timely choices. Research has implicated the risk factors for the susceptibility and severity of Pott's disease, such as HIV and immunosuppression, poverty, and malnutrition. Based on the current literature available, our group aims to summarize the pathogenesis, clinical features, diagnostic challenges, as well as the known risk factors for Pott's disease within this literature review.

FokI polymorphism of the vitamin D receptor (VDR) gene and susceptibility to tuberculosis: Evidence through a meta-analysis

BACKGROUND

Tuberculosis is one of the top ten causes of deaths worldwide. The deficiency of vitamin D was reported to be associated with the increased susceptibility of tuberculosis. Various previous reports were published to check the association of FokI polymorphism of the vitamin D receptor gene with tuberculosis risk. But their results were inconsistent so, we performed a meta-analysis to know the exact relation of the two.

METHODS

Different databases were screened up to November 2020 with the keywords "Vitamin D receptor", "VDR", and "FokI", along with "Tuberculosis" and "TB" to find the suitable articles. All the statistical analyses were performed by the Open Meta-Analyst program and all p-values were two-tailed with a significance level of 0.05.

RESULTS

No statistically significant association was observed in the allele contrast model (OR_fvs.F = 1.11, 95%CI = 0.99-1.24, p = 0.05, I² = 73.46%), in the dominant model (OR_ff+Ffvs.FF = 1.11, 95%CI = 0.96-1.28, p = 0.14, I² = 71.39%), and in the co-dominant model (OR_Ffvs.FF = 1.05, 95%CI = 0.92-1.21, p = 0.41, I² = 65.97%). However, a significant association was found in the homozygote model (OR_ffvs.FF = 1.32, 95%CI = 1.03-1.69, p = 0.02, I² = 67.02%) and in the recessive model (OR_{FF+Ff vs.ff} = 1.26, 95%CI = 1.03-1.54, p = 0.02, I² = 58.01%). Further analysis was performed on the bases of the ethnicity. In Asian population a significant association was found in the homozygote model (OR_ffvs.FF = 1.57, 95%CI = 1.12-2.21, p = 0.008, I² = 70.37%) and in the recessive model (OR_{FF+Ff vs.ff} = 1.43, 95%CI = 1.08-1.89, p = 0.01, I² = 63.13%).

CONCLUSION

In conclusion, a significant association of FokI with tuberculosis susceptibility was found in the overall analysis and in the Asian population.

Investigation of genetic susceptibility to Mycobacterium tuberculosis (VDR and IL10 genes) in a population with a high level of substructure in the Brazilian Amazon region

OBJECTIVES

Tuberculosis (TB) is an infectious and contagious disease that has been very influential in human history and presents high rates of mortality. The objective of this study was to investigate the association of VDR, IL10, and SLC11A1 gene polymorphisms with susceptibility to the presence of Mycobacterium tuberculosis infection.

METHODS

A total of 135 patients with confirmed TB and 141 healthy individuals were included in the analysis. Blood samples were collected for DNA extraction. Genotyping of the polymorphisms in the VDR and IL10 genes was performed by real-time PCR, and genotyping of the polymorphisms in the SLC11A1 gene by conventional PCR, followed by visualization in polyacrylamide gel. The genomic ancestry was obtained using an autosomal panel with 48 insertion/deletion ancestry-informative markers.

RESULTS

Polymorphisms TaqI (TT, p=0.004), FokI (CC and CC+CT, p=0.012 and p=0.003, respectively), and BsmI (GG, p=0.008) in the VDR gene, as well as A-592C (GC+AG, p=0.001) in the IL10 gene, were significantly associated with susceptibility to TB In addition, high production of VDR combined with low production of IL10 showed protection for the TB group (p=0.035).

CONCLUSIONS

The VDR polymorphisms may confer an increased risk and the IL10 haplotype may be a protection factor for the presence of M. tuberculosis infection in the Brazilian population.

Association between Polymorphisms of Vitamin D Receptor and Lung Cancer Susceptibility: Evidence from an Updated Meta-analysis

Purpose: The aim of this meta-analysis was to investigate polymorphism of Bsm1, Apal, Taq1 and Cdx-2 in vitamin D receptor (VDR) associations in relation to lung cancer (LC) susceptibility.

Methods: 9 literatures were recruited into this meta-analysis from PubMed, PMC, Embase, Web of Science, Cochrane library and CNKI. STATA version 15.1 was used for statistical tests. The heterogeneity was tested using I² statistics. According to the value of I², the random-effect model (REM) or fixed-effect model (FEM) was selected to combine data from studies, respectively. Potential publication bias was evaluated by Egger's test. Sensitivity analysis was also performed to evaluate the stability and reliability in results.

Results: Decreased susceptibility of LC was found in all genetic models contrast in Bsm1 gene of VDR (a vs. A: OR = 0.62, 95 % CI = 0.44-0.87; aa vs. AA: OR = 0.76, 95 % CI = 0.60-0.96; Aa vs. AA: OR = 0.59, 95 % CI = 0.39-0.88; aa vs. AA+Aa: OR = 0.80, 95 % CI = 0.64-0.99; Aa+aa vs. AA: OR = 0.57, 95 % CI = 0.37-0.86). The similar results were also found in partial genetic models of Taq1 (a vs. A: OR = 0.88, 95 % CI = 0.79-0.98; aa vs. AA+Aa: OR = 0.84, 95 % CI = 0.73-0.98) and Cdx-2 (Aa vs. AA: OR = 0.80, 95 % CI = 0.66-0.98; Aa+aa vs. AA: OR = 0.79, 95 % CI = 0.65-0.96). Likewise, significant correlation between Bsm1, Taq1 polymorphism and LC risk was detected among Asians. Cdx-2 polymorphism was considered as a protective factor in Caucasians, whereas no association of Apal polymorphism with LC risk was observed in Asians and Caucasians for all genetic models.

Conclusion: The results of this meta-analysis suggested that Bsm1, Taq1 and Cdx-2 polymorphism may contribute to lung cancer susceptibility, more studies need be conducted to confirm in the future.

Associations between vitamin D receptor genetic variants and tuberculosis: a meta-analysis

We performed a meta-analysis to evaluate potential associations between vitamin D receptor (VDR) genetic variants and tuberculosis (TB). Systematic literature research was conducted in PubMed, Web of Science, and Embase. We calculated odds ratios (ORs) and 95% confidence intervals (CIs) to estimate strength of associations in all possible genetic models, and P values ≤ 0.05 were considered to be statistically significant. In total, 42 studies were enrolled for analyses. Pooled overall analyses suggested that VDR rs1544410 (dominant model: P = 0.02; allele model: P = 0.03) and rs731236 (dominant model: P = 0.04; recessive model: P = 0.02; allele model: P = 0.01) variants were significantly associated with TB. Further subgroup analyses by ethnicity revealed that rs1544410 (dominant and allele models) and rs731236 (dominant, recessive, and allele models) variants were both significantly associated with TB in South Asians. When we stratified data by type of disease, positive results were detected for rs7975232 variant in EPTB (dominant, recessive, over-dominant, and allele models) subgroup, and for rs2228570 variant in PTB (dominant, recessive, and allele models) and EPTB (dominant, recessive, over-dominant, and allele models) subgroups. Our meta-analysis supported that rs7975232, rs1544410, rs2228570, and rs731236 variants might serve as genetic biomarkers of certain types of TB.

Vitamin D receptor gene (FokI, TaqI, BsmI, and ApaI) polymorphisms in children with urinary tract infection

BACKGROUND

Little is known about the genetic background of urinary tract infection (UTI) in children.

METHODS

In this study, vitamin D receptor (VDR) gene polymorphisms were compared between 60 children with UTI (case group) and 60 healthy children (control group). DNA extraction, polymerase chain reaction, and the restriction fragment length polymorphism methods were used to perform the genetic analysis.

RESULTS

There was a significant difference between the case and control groups for VDR gene, ApaI and Bsml, polymorphisms (P < 0.05). The frequency of VDR Bb, bb, Aa, and aa genotypes, and the b and a alleles in the case group was significantly higher than that in the control group (P < 0.05). A significant difference was also found between lower UTI and acute pyelonephritis groups for the VDR Apal and Bsml genotypes (P < 0.05). There was no significant difference between children with first UTI and those with more than one UTI for VDR gene polymorphisms (P > 0.05).

CONCLUSION

This study showed that there is a significant relationship between VDR gene, Apal and Bsml, polymorphisms and UTI in children. The results indicate that these polymorphisms may play a role in pathogenesis of UTI.

Identification of HLA-DQA1 as a Susceptibility Gene for Spinal Tuberculosis by Exome Sequencing

Background

Spinal tuberculosis (STB) is the main cause of bone and joint tuberculosis. This study aimed to screen and analyze the susceptibility genes for STB using whole-exome sequencing (WES).

Material/Methods

All exon regions of peripheral blood DNA from 6 STB patients were captured and sequenced using WES and the sequencing data were analyzed by modern bioinformatics methods to identify disease-causing mutations. Sanger sequencing was then used to validate the mutation sites in normal controls (207) and STB patients (193). The mRNA expression of the mutant gene and the serum levels of IL-6 and TNF-α were detected using qPCR or ELISA assay, respectively.

Results

A nonsynonymous single-nucleotide polymorphism (SNP) in the gene HLA-DQA1 (rs796778515, c.592delCinsG, CAG to GAG, p.Q198E) was identified and further validated by Sanger sequencing. The percentage of the 3 genotypes C/C, C/G and G/G in STB patients and normal controls were 37.3%, 32.1%, and 30.6% and 47.8%, 33.8%, and 18.4%, respectively. Furthermore, the C>G mutation was significantly associated with the occurrence of STB. In addition, the levels of HLA-DQA1 mRNA were significantly lower in blood cells from STB patients compared with normal controls, while the serum levels of IL-6 and TNF-α were significantly higher.

Conclusions

The C>G mutation in the HLA-DQA1 gene was associated with the occurrence of STB. This variation may result in the decreased level of HLA-DQA1 mRNA and increased serum levels of IL-6 and TNF-α, which finally led the STB susceptibility.

Spinal tuberculosis: review of current management

Tuberculosis (TB) remains endemic in many parts of the developing world and is increasingly seen in the developed world due to migration. A total of 1.3 million people die annually from the disease. Spinal TB is the most common musculoskeletal manifestation, affecting about 1 to 2% of all cases of TB. The coexistence of HIV, which is endemic in some regions, adds to the burden and the complexity of management. This review discusses the epidemiology, clinical presentation, diagnosis, impact of HIV and both the medical and surgical options in the management of spinal TB. Cite this article: Bone Joint J 2018;100-B:425-31.

Regulation of Immune Function by Vitamin D and Its Use in Diseases of Immunity

Evidence exists for a role for vitamin D and its active metabolites in modulating immune functions. In animal models, vitamin D deficiency is associated with a higher risk for autoimmunity in genetically predisposed subjects and increases in susceptibility to infections. In addition, high-dose vitamin D can improve immune health, prevent autoimmunity, and improve defense against infections. In humans, evidence exists on associations between vitamin D deficiency and impaired immune function, leading to autoimmunity in genetically predisposed people and increased risk for infections; data on therapeutic immune effects of vitamin D supplementation when vitamin D levels are already sufficient are lacking.

Association between Vitamin D receptor (Cdx2, Fok1, Bsm1, Apa1, Bgl1, Taq1, and Poly (A)) gene polymorphism and breast cancer: A systematic review and meta-analysis

The purpose of this systemic review and meta-analysis was to examine the relationship between VDR gene polymorphisms and breast cancer. Literature was searched through PubMed database, Google scholar, and the web of knowledge from December 2015 to January 2017 and consists of 34 studies (26,372 cases and 32,883 controls). All statistical measures were done using STATA version 11.2. The heterogeneity among studies was tested using I² statistics. Mantel-Haenszel method and DerSimonian-Laird method were used to combine data from studies using both random-effect model and fixed-effect model, respectively. Potential publication bias was evaluated by Egger's test. Sensitivity analysis was also performed to evaluate the quality and consistency in results. The results of this meta-analysis revealed that VDR gene polymorphisms (Bsm1 bb vs BB; SOR = 1.18, 95% CI = 1.054-1.322, Apa1 aa vs AA; SOR = 1.18, 95% CI = 0.87-1.59, Poly (A) LL vs SS; SOR = 1.41, 95% CI = 1.06-1.88, Fok1 ff + Ff vs FF; SOR = 1.25, 95% CI = 0.896-1.759, Apa1 aa+Aa vs AA; SOR = 1.13, 95% CI = 0.95-1.35, Poly (A) LL + LS vs SS; SOR = 1.19, 95% CI = 1.00-1.43, Poly (A) L vs S; SOR = 1.18, 95% CI = 1.03-1.35) are associated with the breast cancer. Cdx2, Bgl1, and Taq1 do not show association with breast cancer. Thus, the finding of this meta-analysis concluded that VDR Bsm1, Apa1, Fok1, and Poly (A) gene polymorphisms may be susceptible for breast cancer development.

Genetic analysis of the Vitamin D receptor start codon polymorphism (FokI) in cervical vertebra and lumbar spine pathologies: a meta-analysis

BACKGROUND

Vitamin D receptor (VDR) FokI polymorphism has been reported to influence the risk of spinal diseases. However, several studies suggest inconsistent results. Therefore, we performed this analysis to reveal the accurate relationship between VDR FokI polymorphism and spinal diseases.

MATERIALS AND METHODS

8 articles accord with the strict inclusion and exclusion criteria. 1116 cases and 1263 controls are entered into this analysis. The pooled odds ratios (ORs) and 95% confidence intervals (CI) are calculated to evaluate the association between VDR gene polymorphism and spinal diseases.

RESULT

The results suggest that allele F is a risk factor for spinal diseases and the difference is significant (F vs. f: OR = 1.151, 95% CI, 1.020-1.300). For the genotype analysis of VDR FokI, no statistical differences exist in the models of heterozygote comparison (Ff vs. ff), homozygote comparison (FF vs. ff) and dominant model (FF + Ff vs. ff) (p > 0.05). However, in recessive model (FF vs. Ff + ff), there is a significant association between VDR polymorphism and spinal diseases (OR = 1.209, 95% CI, 1.017-1.436). In subgroup analysis, the results show that allele F is a risk factor for spinal diseases in each estimation. In hospital-based subgroup, the significant differences exist in FF vs. ff and FF vs. Ff + FF models. In degenerative spine diseases group, the results are consistent with that of overall studies.

CONCLUSIONS

According to results of this meta-analysis, allele F is associated with the increased risk of spinal diseases. FF genotype may contribute to the susceptibility of spinal diseases. Therefore, VDR FokI polymorphism is related with spinal diseases.

Association of IFNG gene polymorphisms with pulmonary tuberculosis but not with spinal tuberculosis in a Chinese Han population

Spinal tuberculosis (STB) is an extrapulmonary form of tuberculosis (TB) caused by Mycobacterium tuberculosis (Mtb), which accounts for around 2% of all TB cases and can lead to spine degeneration. It is widely accepted that host genetic factors participate in the pathogenesis of active TB, but the factors controlling which TB form will manifest after Mtb infection remain unknown. We hypothesized that a genetic difference may exist between the development of STB and pulmonary tuberculosis (PTB). Here, three single nucleotide polymorphisms (SNPs) in the IFNG gene (rs2069718), IRGM gene (rs10065172), and MBL2 gene (rs11003125) were genotyped among 183 PTB patients, 177 STB patients, and 360 healthy controls from the Chinese Han population. We found that rs2069718 genotypes were significantly associated with PTB (TT, p = 0.007; CT, p = 0.008) but not STB, and the TT genotype (p = 0.046) of rs2069718 were less common in PTB than in STB. In contrast, neither PTB nor STB were found to be associated with rs10065172 and rs11003125. Overall, we found a difference in the rs2069718 genetic distribution between the STB and PTB patients in a Chinese Han population. The rs2069718 TT genotype was associated with a protective role in PTB but not STB development during active Mtb infection.

[Association of vitamin D receptor gene polymorphisms with susceptibility to bone and joint tuberculosis in Chinese Han population]

OBJECTIVE

To investigate the association between vitamin D receptor (VDR) gene Apa I polymorphism and the susceptibility to bone and joint tuberculosis in Chinese Han population.

METHODS

Between May, 2015 and June, 2016, 100 patients with bone and joint tuberculosis and 100 healthy volunteers were recruited concomitantly in Heyuan Hospital of Traditional Chinese Medicine. Vitamin D receptor gene Apa I polymorphisms in these subjects were analyzed using SNaPshot.

RESULT

The genotype frequencies of Apa I-AA, Apa I-Aa and Apa I-aa were 51%, 41%, and 8% in the case group and 33%, 55%, and 12% in the control group, respectively, showing significant differences between the two groups (P<0.05). The genotype of Apa I-AA was significantly higher in the case group with an odds ratio (OR) of 2.073 (95% CI: 1.142-3.763).

CONCLUSION

The Apa I polymorphisms of the VDR gene are associated with the susceptibility to bone and joint tuberculosis in Chinese Han population, and individuals with a Apa I-AA genotype are at greater risks to develop bone and joint tuberculosis.

Single nucleotide polymorphisms in the vitamin D pathway associating with circulating concentrations of vitamin D metabolites and non-skeletal health outcomes: Review of genetic association studies

Polymorphisms in genes encoding proteins involved in vitamin D metabolism and transport are recognised to influence vitamin D status. Syntheses of genetic association studies linking these variants to non-skeletal health outcomes are lacking. We therefore conducted a literature review to identify reports of statistically significant associations between single nucleotide polymorphisms (SNP) in 11 vitamin D pathway genes (DHCR7, CYP2R1, CYP3A4, CYP27A1, DBP, LRP2, CUB, CYP27B1, CYP24A1, VDR and RXRA) and non-bone health outcomes and circulating levels of 25-hydroxyvitamin D (25[OH]D and 1,25-dihydroxyvitamin D (1,25[OH]₂D). A total of 120 genetic association studies reported positive associations, of which 44 investigated determinants of circulating 25(OH)D and/or 1,25(OH)₂D concentrations, and 76 investigated determinants of non-skeletal health outcomes. Statistically significant associations were reported for a total of 55 SNP in the 11 genes investigated. There was limited overlap between genetic determinants of vitamin D status and those associated with non-skeletal health outcomes: polymorphisms in DBP, CYP2R1 and DHCR7 were the most frequent to be reported to associate with circulating concentrations of 25(OH)D, while polymorphisms in VDR were most commonly reported to associate with non-skeletal health outcomes, among which infectious and autoimmune diseases were the most represented.

The Role of Host Genetics (and Genomics) in Tuberculosis

Familial risk of tuberculosis (TB) has been recognized for centuries. Largely through studies of mono- and dizygotic twin concordance rates, studies of families with Mendelian susceptibility to mycobacterial disease, and candidate gene studies performed in the 20th century, it was recognized that susceptibility to TB disease has a substantial host genetic component. Limitations in candidate gene studies and early linkage studies made the robust identification of specific loci associated with disease challenging, and few loci have been convincingly associated across multiple populations. Genome-wide and transcriptome-wide association studies, based on microarray (commonly known as genechip) technologies, conducted in the past decade have helped shed some light on pathogenesis but only a handful of new pathways have been identified. This apparent paradox, of high heritability but few replicable associations, has spurred a new wave of collaborative global studies. This review aims to comprehensively review the heritability of TB, critically review the host genetic and transcriptomic correlates of disease, and highlight current studies and future prospects in the study of host genomics in TB. An implicit goal of elucidating host genetic correlates of susceptibility to Mycobacterium tuberculosis infection or TB disease is to identify pathophysiological features amenable to translation to new preventive, diagnostic, or therapeutic interventions. The translation of genomic insights into new clinical tools is therefore also discussed.

Vitamin D receptor gene FokI polymorphisms and tuberculosis susceptibility: a meta-analysis

INTRODUCTION

The association between FokI polymorphism of vitamin D receptor (VDR) and tuberculosis (TB) susceptibility has been investigated previously; however, the results were inconsistent and conflicting. In the present study, a meta-analysis was performed to assess the relationship between VDR FokI gene polymorphism and the risk of TB.

MATERIAL AND METHODS

Databases including PubMed and Embase were searched for genetic association studies of FokI polymorphism of vitamin D receptor (VDR) and TB. Data were extracted by two independent authors and the pooled odds ratio (OR) with 95% confidence interval (CI) was calculated to assess the strength of the association between VDR FokI gene polymorphism and TB risk. Meta-regression and subgroup analyses were performed to identify the source of heterogeneity.

RESULTS

Thirty-four studies with a total of 5669 cases and 6525 controls were reviewed in the present meta-analysis. A statistically significant correlation was found between VDR FokI gene polymorphism and increased TB risk in two comparison models: the homozygote model (ff vs. FF: OR = 1.37, 95% CI: 1.17-1.60; P_{heterogeneity} = 0.001) and the recessive model (ff vs. Ff + FF: OR = 1.32, 95% CI: 1.14-1.52; P_{heterogeneity} = 0.006). Meta-regression found no source contributing to heterogeneity. However, sub-group analyses revealed that there was a statistically increased TB risk in the East and Southeast Asian population.

CONCLUSIONS

Synthesis of the available studies suggests that homozygosity for the FokI polymorphism of the VDR gene might be associated with an increased TB risk, especially in the East and Southeast Asian population. Additional well-designed, larger-scale epidemiological studies among different ethnicities are needed.

25-Hydroxy Vitamin D, Vitamin D Receptor and Toll-like Receptor 2 Polymorphisms in Spinal Tuberculosis: A Case-Control Study

Vitamin D deficiency and vitamin D receptor (VDR) gene abnormalities confer susceptibility to tuberculosis. Toll-like receptors (TLRs), such asTLR-2, are also important mediators of inflammatory response against Mycobacterium tuberculosis. We evaluated serum vitamin D, and VDR and TLR-2 gene polymorphisms in patients with spinal tuberculosis.This study comprised of 3 groups: spinal tuberculosis, pulmonary tuberculosis, and controls (each with 106 subjects). Enzyme-linked immunosorbent assay was used to measure vitamin D levels, and polymerase chain reaction-sequencing method was used to analyze VDR and TLR-2 gene polymorphisms. Patients were followed up for 6 months.Vitamin D deficiency was significantly more prevalent in patients with spinal tuberculosis (P < 0.001) and pulmonary tuberculosis (P = 0.011), versus controls. The heterozygous and mutant genotypes of VDR TaqI gene were significantly associated with spinal tuberculosis (P < 0.001; odds ratio [OR] 4.74 [2.45-9.18]) and pulmonary tuberculosis (P < 0.001; OR 3.52 [1.80-6.88]) when compared with controls. The heterozygous and mutant variants of VDR ApaI gene were significantly more common in patients with spinal tuberculosis in comparison with patients with pulmonary tuberculosis (P < 0.001; OR 2.90 [1.65-5.10]) and controls (P < 0.001; OR 6.56 [3.41-12.61]). We did not observe any significantly different results for TLR-2 gene polymorphisms. Vitamin D deficiency, VDR, and TLR-2 polymorphisms did not affect the 6-month disability.Vitamin D deficiency and VDR gene polymorphisms are significantly more prevalent in people with pulmonary and spinal tuberculosis. They may, in isolation or collectively, confer susceptibility to pulmonary and spinal tuberculosis.

Vitamin D Receptor Gene FokI Polymorphism Contributes to Increasing the Risk of Tuberculosis: An Update Meta-Analysis

The association between vitamin D receptor (VDR) FokI polymorphism and tuberculosis (TB) risk remains a matter of debate. Potential selection bias exists in most studies using HIV-positive TB patients.An update meta-analysis was carried out to derive a more reliable assessment of the association between FokI polymorphisms and TB risk, especially in HIV-negative TB patients. All major databases from inception to June 2015 were searched for all publications that studied the association between FokI polymorphism and TB risk. The odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) were calculated according to the frequencies of genotypes.In total, 32 studies with 4894 cases and 5319 controls were included in this meta-analysis. In the overall analysis, the estimated OR was 1.34 (95% CI=1.091-1.646, P = 0.005) in the best genetic model (recessive model, ff vs fF+FF) with moderate heterogeneity (I = 32.2%, P = 0.043). In the subgroup analysis stratified by HIV status, significant associations were found only in the HIV-negative TB group (OR = 1.60, 95% CI = 1.180-2.077, P = 0.002; I = 29.5%, and P = 0.141 for heterogeneity). In the subgroup analysis stratified by ethnicity, significant associations were found in the Asian group (OR = 1.65, 95% CI = 1.205-2.261, P = 0.002; I = 43.9%, and P = 0.024 for heterogeneity), but not in the Caucasian group (OR = 1.09, 95% CI = 0.762-1.547, P = 0.649; I = 0.0%, and P = 0.740 for heterogeneity) and African group (OR = 0.99, 95% CI = 0.726-1.341, P = 0.934; I = 43.9%, and P = 0.024 for heterogeneity).This meta-analysis confirms that VDR FokI polymorphism contributes to the risk of TB, especially in HIV-negative TB patients and in the Asian group. Further studies are required to clarify the role of the FokI polymorphism in HIV-positive TB and in other ethnic groups.

Vitamin D Receptor Gene FOKI Polymorphism Contributes to Increasing the Risk of HIV-Negative Tuberculosis: Evidence from a Meta-Analysis

Background

Vitamin D receptor (VDR) gene FokI polymorphism have been studied in relation to tuberculosis (TB) in many populations and provided inconsistent results. In this study, we carried out a meta-analysis to derive a more reliable assessment on FokI polymorphism and the risk of HIV-negative TB.

Methods

The Embase, PubMed, and Cochrane Library databases were used to undertake a comprehensive systematic literature review of all current published VDR gene FOKI association studies aimed at the risk of TB up to June 30, 2015. Odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) were used to measure the strength of the models.

Results

A total of 14 studies (1,668 cases and 1,893 controls) were retrieved in the meta-analysis. The pooled OR was 1.60 (95% = 1.28–1.97, P<0.001; I² = 29.5%, and P = 0.141 for heterogeneity) in the best genetic model (recessive model: ff vs. fF+FF). In the subgroup analysis by ethnicities, a significantly increased risk was found in the Asian group (OR = 1.82, 95% CI = 1.42–2.33, P<0.001; I² = 31.0%, and P = 0.150 for heterogeneity) in the recessive model. Similarly, significant associations were also found in the polymerase chain reaction-restriction fragment length polymorphism group, high-quality studies, and the population based or hospital based groups. Moderate heterogeneity was found in this study.

Conclusion

Our results suggested that VDR FokI polymorphism contributes to increasing the risk of TB in HIV-negative individuals, especially in the Asian region. Further studies on this topic in other races are expected to be conducted in future.

Mycobacterium avium Complex Osteomyelitis in Persons With Human Immunodeficiency Virus: Case Series and Literature Review

In persons with advanced immunosuppression, Mycobacterium avium complex (MAC) typically causes disseminated disease with systemic symptoms. We report 2 cases in which MAC caused localized osteomyelitis in human immunodeficiency virus (HIV)-infected individuals on antiretroviral therapy with rising CD4 counts. We summarize 17 additional cases of HIV-associated MAC osteomyelitis from the literature and compare CD4 count at presentation for vertebral cases versus nonvertebral cases, which reveals a significantly higher CD4 at presentation for vertebral cases (median 251 cells/µL vs 50 cells/µL; P = .043; Mann-Whitney U test). The literature review demonstrates that the majority of cases of MAC osteomyelitis, especially vertebral, occurs in individuals with CD4 counts that have increased to above 100 cells/µL on antiretroviral therapy. Among HIV-infected individuals with osteomyelitis, MAC should be considered a possible etiology, particularly in the setting of immune reconstitution.

Association between vitamin D receptor polymorphisms and haplotypes with pulmonary tuberculosis

The vitamin D receptor (VDR) is an important factor in activating immune response in different infectious diseases. The aim of the present study was to investigate the association between the VDR gene polymorphisms and pulmonary tuberculosis (PTB). The case control study was performed on 120 PTB patients and 131 healthy controls. Genetic analysis was performed by polymerase chain reaction and the restriction fragment length polymorphism method. The VDR Fok1 Ff genotype was associated with TB and the risk of PTB was two times higher in individuals with the Ff genotype. A higher frequency of f allele was observed in PTB patients and therefore, the f allele may be a risk factor for PTB susceptibility. There were no associations between the Taq1 and Bsm1 polymorphisms and PTB. In addition, haplotype analysis showed that the f-T-B and f-t-b haplotypes (Fok1, Taq1 and Bsm1) may have the potential to increase PTB susceptibility. In conclusion, the Ff genotype and f allele of the VDR Fok1 polymorphism were associated with PTB susceptibility. In addition, the f-T-B and f-t-b haplotypes may be the susceptible haplotypes for PTB.

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.

Vitamin D receptor gene polymorphisms on the risk of tuberculosis, a meta-analysis of 29 case-control studies

The relationship of four potentially functional polymorphisms of the vitamin D receptor (VDR) gene, ApaI, BsmI, FokI and TaqI , with tuberculosis susceptibility were considered. The aim of this meta-analysis was to explore the association between the four polymorphisms and tuberculosis risk in different ethnic backgrounds. Eligible case-control studies that were catalogued before April 1^st 2013 were enrolled, and the heterogeneity between the studies was evaluated using a χ² based Q-test. Fixed and random effect models were built to evaluate the association of the four polymorphisms with the risk of tuberculosis, and the association between the four polymorphisms and tuberculosis was expressed as the odds ratio (OR) and 95% confidence interval (CI). Finally, twenty nine qualified studies were enrolled for this meta-analysis that included 6179 tuberculosis cases and 6585 healthy controls. The variant homozygote genotype of the FokI polymorphism was associated with a significantly increased risk of tuberculosis when compared to the heterozygote and wild type homozygote genotypes in the Chinese population (ff vs. Ff+FF: OR_recessive=1.97, 95%CI: 1.32-2.93, P_bonferroni=0.0032; heterogeneity test: χ²=0.24, P=0.62). For European subjects, the homozygote and heterozygote genotypes of the BsmI polymorphism were associated with a significantly decreased risk of tuberculosis when compared to the wild type homozygote (bb+Bb vs. BB: OR_dominant=0.41, 95%CI, 0.22-0.76, P_bonferroni=0.02; heterogeneity test: χ²=2.59, P=0.11). Based on the above results, we conclude that variants of the VDR gene that are homozygous for the FokI polymorphism might be more susceptible to tuberculosis in Chinese. Furthermore, larger sample studies are warranted to confirm the protective effects of BsmI variants on tuberculosis in the Europeans.

Monocyte chemoattractant protein-1 in spinal tuberculosis: -362G/C genetic variant and protein levels in Chinese patients

The objective of the study is to explore the possible association of the monocyte chemoattractant protein (MCP)-1-362G/C genetic polymorphism and plasma levels of MCP-1 in patients with spinal tuberculosis (TB). The MCP-1-362G/C (rs2857656) polymorphism and blood levels of MCP-1 in patients with spinal TB and healthy subjects were evaluated and compared. Three hundred thirty-two patients and 336 healthy subjects were genotyped using polymerase chain reaction and Sanger DNA sequencing technology. MCP-1 plasma levels were measured by a solid-phase enzyme-linked immunosorbent assay. When comparisons were made between patients and controls, the frequency of the MCP-1-362*C minor allele (55.4% versus 47.5%, P = 0.004, odds ratio [OR] = 1.376, 95% confidence interval [CI]: 1.109-1.706) and the carriers of the MCP-1-362*C allele (80.7% versus 71.4%, P = 0.005, OR = 1. 657, 95% CI: 1.167-2.403) were over-represented in patients. The mean MCP-1 plasma level in spinal TB patients was significantly higher than in controls (154.44 ± 68.81 pg/mL versus 36.69 ± 21.71 pg/mL, t = -5.85, P < 0.001). The patients with the CC genotype had the highest MCP-1 level (150.63 ± 73.89 pg/mL), followed by those with the GC genotype (108.63 ± 52.09 pg/mL, t = 2.351, P = 0.022) and GG (91.29 ± 54.31 pg/mL, t = 3.091, P = 0.003) homozygotes. We report the association of the -362G/C genetic polymorphism and increased plasma levels of MCP-1 in patients with spinal TB and nominate the -362*C minor allele as a risk factor for spinal TB in the Chinese population.

Forked osteotomy arthroplasty for elbow tuberculosis: six years of follow-up

BACKGROUND

Elbow tuberculosis (TB) is not rare in China. Most patients are diagnosed when it is at an advanced stage and with bony ankylosis complications. For a developing country, such as China, it is important for there to be safe and cost-effective procedures.

MATERIALS AND METHODS

A retrospective study was designed to assess the effects of improved forked excision arthroplasty for treating elbow TB. There were 20 patients (average age, 48.45 years). For all patients, the preoperative diagnosis was elbow TB at an advanced stage. All patients underwent forked excision arthroplasty. Patients were evaluated preoperatively and postoperatively with the Mayo's elbow performance score (MEPS). Mean follow-up was at 74.4 months.

RESULTS

At the last follow-up, the mean postoperative MEPS was 83.7 compared with the preoperative MEPS of 20.25. Results of Mayo's elbow performance index were excellent in seven patients, good in 12 and fair in one, and none were poor. The range of elbow motion also improved significantly.

CONCLUSION

This study of forked elbow excision arthroplasty has shown promising results for treating elbow TB. Most patients had ideal postoperative outcomes and exhibited painless elbow joints, with satisfactory functional recovery at medium-term follow-up. Further studies with longer follow-up are warranted.

LEVEL OF EVIDENCE

III.

How important is vitamin D in preventing infections?

Interaction with the immune system is one of the most recently established nonclassic effects of vitamin D (VitD). For many years, this was considered to be limited to granulomatous diseases in which synthesis of active 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) or calcitriol is known to be increased. However, recent reports have supported a role for 1,25(OH)2D3 in promoting normal function of the innate and adaptive immune systems. Crucially, these effects seem to be mediated not only by the endocrine function of circulating calcitriol but also via paracrine (i.e., refers to effects to adjacent or nearby cells) and/or intracrine activity (i.e., refers to a hormone acting inside a cell) of 1,25(OH)2D3 from its precursor 25(OH)D3, the main circulating metabolite of VitD. The ability of this vitamin to influence human immune responsiveness seems to be highly dependent on the 25(OH)D3 status of individuals and may lead to aberrant response to infection or even to autoimmunity in those who are lacking VitD. The potential health significance of this has been underlined by increasing awareness of impaired status in populations across the globe. This review will examine the current understanding of how VitD status may modulate the responsiveness of the human immune system. Furthermore, we discuss how it may play a role in host resistance to common pathogens and how effective is its supplementation for treatment or prevention of infectious diseases in humans.

Immunomodulation by vitamin D: implications for TB

TB remains a major cause of mortality throughout the world. Low vitamin D status has been linked to increased risk of TB and other immune disorders. These observations suggest a role for vitamin D as a modulator of normal human immune function. This article will detail the cellular and molecular mechanisms by which vitamin D regulates the immune system and how vitamin D insufficiency may lead to immune dysregulation. The importance of vitamin D bioavailability as a mechanism for defining the immunomodulatory actions of vitamin D and its impact on TB will also be discussed. The overall aim will be to provide a fresh perspective on the potential benefits of vitamin D supplementation in the prevention and treatment of TB.

An update on vitamin D and human immunity

In the last 5 years, there has been a remarkable change in our understanding of the health benefits of vitamin D. The classical actions of vitamin D as a determinant of mineral metabolism and rachitic bone disease have been expanded to include a broader role in skeletal homoeostasis and prevalent bone disorders such as osteoporosis. However, it is the nonskeletal function of vitamin D that has attracted most attention. Although pluripotent responses to vitamin D have been recognized for many years, our new perspective on nonclassical vitamin D function stems from two more recent concepts. The first is that impaired, vitamin D status is common to many populations across the globe. This has prompted studies to explore the health impact of suboptimal circulating levels of vitamin D, with association studies linking vitamin D 'insufficiency' to several chronic health problems including autoimmune and cardiovascular disease, hypertension and common cancers. In support of a broader role for vitamin D in human health, studies in vitro and using animal models have highlighted immunomodulatory and anticancer effects of vitamin D that appear to depend on localized activation of vitamin D. The conclusion from these reports is that many nonclassical actions of vitamin D are independent of conventional vitamin D endocrinology and are therefore more sensitive to variations in vitamin D status. The current review summarizes these developments, with specific reference to the newly identified effects of vitamin D on the immune system, but also highlights the challenges in translating these observations to clinical practice.

Spinal tuberculosis: a review

Spinal tuberculosis is a destructive form of tuberculosis. It accounts for approximately half of all cases of musculoskeletal tuberculosis. Spinal tuberculosis is more common in children and young adults. The incidence of spinal tuberculosis is increasing in developed nations. Genetic susceptibility to spinal tuberculosis has recently been demonstrated. Characteristically, there is destruction of the intervertebral disk space and the adjacent vertebral bodies, collapse of the spinal elements, and anterior wedging leading to kyphosis and gibbus formation. The thoracic region of vertebral column is most frequently affected. Formation of a 'cold' abscess around the lesion is another characteristic feature. The incidence of multi-level noncontiguous vertebral tuberculosis occurs more frequently than previously recognized. Common clinical manifestations include constitutional symptoms, back pain, spinal tenderness, paraplegia, and spinal deformities. For the diagnosis of spinal tuberculosis magnetic resonance imaging is more sensitive imaging technique than x-ray and more specific than computed tomography. Magnetic resonance imaging frequently demonstrates involvement of the vertebral bodies on either side of the disk, disk destruction, cold abscess, vertebral collapse, and presence of vertebral column deformities. Neuroimaging-guided needle biopsy from the affected site in the center of the vertebral body is the gold standard technique for early histopathological diagnosis. Antituberculous treatment remains the cornerstone of treatment. Surgery may be required in selected cases, e.g. large abscess formation, severe kyphosis, an evolving neurological deficit, or lack of response to medical treatment. With early diagnosis and early treatment, prognosis is generally good.