Adverse Pregnancy Outcomes Among Women with Human Immunodeficiency Virus Taking Isoniazid Preventive Therapy During the First Trimester.

BACKGROUND: Isoniazid preventive therapy (IPT) is recommended for tuberculosis prevention yet data on the safety of first-trimester pregnancy exposure are limited. METHODS: Planned secondary analysis in a TB prevention trial of adverse pregnancy outcomes among participants assigned to 9-month IPT who became pregnant during (IPT-exposed) or after (unexposed) IPT. Regression models compared binary outcomes of a composite adverse outcome (any non-live birth, excluding induced abortion); preterm delivery <37 weeks; and low birth weight <2500 g) among exposure groups. Models were adjusted for latent TB infection, maternal age, CD4 count, and antiretroviral therapy (ART). RESULTS: In total, 128 participants had a known pregnancy outcome; 39 IPT-exposed and 89 unexposed. At pregnancy outcome, ART use was lower in IPT-exposed (79%) than unexposed women (98%). Overall, 29 pregnancies ended in a composite adverse outcome (25 spontaneous abortions, 2 stillbirths and 2 ectopic pregnancies), 15 preterm deliveries, and 10 infants with low birth weight. IPT was associated with the composite adverse outcome adjusting for covariates at enrollment (adjusted relative risk [aRR] 1.98; 95% confidence interval [CI] 1.15, 3.41), but the effect was attenuated when adjusted for covariates at pregnancy outcome (aRR 1.47; 95% CI .84, 2.55); IPT was not associated with preterm delivery (relative risk [RR] 0.87; 95% CI .32-2.42) or low birth weight (RR 1.01; 95% CI .29, 3.56). CONCLUSIONS: First-trimester IPT exposure was associated with nearly two-fold increased risk of fetal demise, mostly spontaneous abortion, though the association was attenuated when adjusted for covariates proximal to pregnancy outcome including ART use. Further study is needed to inform TB prevention guidelines.

Efficacy and safety of rifampicin-based triple therapy for non-puerperal mastitis: A single-arm, open-label, prospective clinical trial.

OBJECTIVES: To assess the efficacy and safety of rifampicin-based triple therapy (rifampicin, isoniazid, and ethambutol) for treating NPM. METHODS: This single-center, single-arm, prospective clinical trial was conducted at the Second Hospital of Shandong University (Jinan, China). Patients with pathologically diagnosed granulomatous lobular mastitis and periductal mastitis received triple drugs, i.e., rifampicin (450 mg/day), isoniazid (300 mg/day), and ethambutol (15 mg/kg/day), until complete response or the investigator decided to discontinue treatment. The primary endpoint was the complete response rate (CRR) assessed by the investigator. The secondary endpoints included the overall remission rate (ORR), recurrence rate (RR), and safety. RESULTS: A total of 218 patients were enrolled in the study between January 1, 2013 and October 31, 2020. With a median follow-up time of 48 months, the CRR and the ORR were 78.44% and 94.04%, respectively. While 13 patients (5.96%) demonstrated no response and 19 relapsed (8.72%). Adverse events (AEs) were not common. The most common AEs during treatment were liver dysfunction (1.83%), gastrointestinal reactions (1.83%), fatigue (1.83%), erythema (1.38%), and menstrual disorders (0.92%). CONCLUSION: Rifampicin, isoniazid, and ethambutol demonstrated promising response rates with acceptable safety profiles in patients with NPM. Further confirmatory trial is warranted in the future. TRIAL REGISTRATION: The study was approved by the Ethics Committee of the Second Hospital of Shandong University and retrospectively registered at the China Clinical Trial Registration Center (registration number: ChiCTR2100049591).

The Effect of Bergenin on Isonicotinic Acid Hydrazide and Rifampicin-Induced Liver Injury Revealed by RNA Sequencing.

Bergenin (BER), a natural component of polyphenols, has a variety of pharmacological activities, especially in improving drug metabolism, reducing cholestasis, anti-oxidative stress and inhibiting inflammatory responses. The aim of this study was to investigate the effects of BER on liver injury induced by isonicotinic acid hydrazide (INH) and rifampicin (RIF) in mice. The mice model of liver injury was established with INH (100 mg/kg)+RIF (100 mg/kg), and then different doses of BER were used to intervene. The pathological morphology and biochemical indicators of mice were detected. Meanwhile, RNA sequencing was performed to screen the differentially expressed genes and signaling pathways. Finally, critical differentially expressed genes were verified by qRT-PCR and Western blot. RNA sequencing results showed that 707 genes were significantly changed in the INH+RIF group compared with the Control group, and 496 genes were significantly changed after the BER intervention. These differentially expressed genes were mainly enriched in the drug metabolism, bile acid metabolism, Nrf2 pathway and TLR4 pathway. The validation results of qRT-PCR and Western blot were consistent with the RNA sequencing. Therefore, BER alleviated INH+RIF-induced liver injury in mice. The mechanism of BER improving INH+RIF-induced liver injury was related to regulating drug metabolism enzymes, bile acid metabolism, Nrf2 pathway and TLR4 pathway.

Screening for Latent Tuberculosis Infection in Adults: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force.

Importance: Latent tuberculosis infection (LTBI) can progress to active tuberculosis disease, causing morbidity and mortality. Objective: To review the evidence on benefits and harms of screening for and treatment of LTBI in adults to inform the US Preventive Services Task Force (USPSTF). Data Sources: PubMed/MEDLINE, Cochrane Library, and trial registries through December 3, 2021; references; experts; literature surveillance through January 20, 2023. Study Selection: English-language studies of LTBI screening, LTBI treatment, or accuracy of the tuberculin skin test (TST) or interferon-gamma release assays (IGRAs). Studies of LTBI screening and treatment for public health surveillance or disease management were excluded. Data Extraction and Synthesis: Dual review of abstracts, full-text articles, and study quality; qualitative synthesis of findings; meta-analyses conducted when a sufficient number of similar studies were available. Main Outcomes and Measures: Screening test accuracy; development of active tuberculosis disease, transmission, quality of life, mortality, and harms. Results: A total of 113 publications were included (112 studies; N = 69 009). No studies directly evaluated the benefits and harms of screening. Pooled estimates for sensitivity of the TST were 0.80 (95% CI, 0.74-0.87) at the 5-mm induration threshold, 0.81 (95% CI, 0.76-0.87) at the 10-mm threshold, and 0.60 (95% CI, 0.46-0.74) at the 15-mm threshold. Pooled estimates for sensitivity of IGRA tests ranged from 0.81 (95% CI, 0.79-0.84) to 0.90 (95% CI, 0.87-0.92). Pooled estimates for specificity of screening tests ranged from 0.95 to 0.99. For treatment of LTBI, a large (n = 27 830), good-quality randomized clinical trial found a relative risk (RR) for progression to active tuberculosis at 5 years of 0.35 (95% CI, 0.24-0.52) for 24 weeks of isoniazid compared with placebo (number needed to treat, 112) and an increase in hepatotoxicity (RR, 4.59 [95% CI, 2.03-10.39]; number needed to harm, 279). A previously published meta-analysis reported that multiple regimens were efficacious compared with placebo or no treatment. Meta-analysis found greater risk for hepatotoxicity with isoniazid than with rifampin (pooled RR, 4.22 [95% CI, 2.21-8.06]; n = 7339). Conclusions and Relevance: No studies directly evaluated the benefits and harms of screening for LTBI compared with no screening. TST and IGRAs were moderately sensitive and highly specific. Treatment of LTBI with recommended regimens reduced the risk of progression to active tuberculosis. Isoniazid was associated with higher rates of hepatotoxicity than placebo or rifampin.

Influence of NAT2 Genotype and Maturation on Isoniazid Exposure in Low-Birth-Weight and Preterm Infants With or Without Human Immunodeficiency Virus (HIV) Exposure.

BACKGROUND: Isoniazid (INH) metabolism depends on the N-acetyl transferase 2 (NAT2) enzyme, whose maturation process remains unknown in low birth weight (LBW) and preterm infants. We aimed to assess INH exposure and safety in infants receiving oral tuberculosis prevention. METHODS: This population pharmacokinetics (PK) analysis used INH and N-acetyl-isoniazid (ACL) concentrations in infants (BW ≤ 4 kg), including preterm, with follow-up for 6 months. PK parameters were described using nonlinear mixed effects modeling. Simulations were performed to assess INH exposure and optimal dosing regimens, using 2 targets: Cmax at 3-6 mg/L and area under the curve (AUC) ≥ 10.52 mg h/L. RESULTS: We included 57 infants (79% preterm, 84% LBW) in the PK analysis, with a median (range) gestational age of 34 (28.7-39.4) weeks. At the time of sampling, postnatal age was 2.3 (0.2-7.3) months and weight (WT) was 3.7 (0.9-9.3) kg. NAT2 genotype was available in 43 (75.4%) patients (10 slow, 26 intermediate, and 7 fast metabolizers). Ninety percent of NAT2 maturation was attained by 4.4 post-natal months. WT, postmenstrual age, and NAT2 genotype significantly influenced INH exposure, with a 5-fold difference in AUC between slow and fast metabolizers for the same dose. INH appeared safe across the broad range of exposure for 61 infants included in the safety analysis. CONCLUSIONS: In LBW/preterm infants, INH dosing needs frequent adjustment to account for growth and maturation. Pharmacogenetics-based dosing regimens is the most powerful approach to deliver safe and equalized exposures for all infants, because NAT2 genotype highly impacts INH pharmacokinetic variability.

Association between 9-month isoniazid prophylaxis of latent tuberculosis and severe hepatitis in patients treated with TNF inhibitors.

To investigate associations between isoniazid for latent tuberculosis and risk of severe hepatitis, affecting patients with rheumatoid arthritis or ankylosing spondylitis whose treatment includes tumor necrosis factor inhibitors. Our self-controlled case series study analyzed Taiwan's National Health Insurance Database from 2003 to 2015 to identify RA or AS patients, aged ≥ 20 years, receiving TNF inhibitors and a 9-month single isoniazid treatment. The outcome of interest was hospitalization due to severe hepatitis. We defined risk periods by isoniazid exposure (days): 1-28, 29-56, 57-84, 85-168, 169-252, and 253-280. To compare risk of severe hepatitis in exposed and non-exposed periods, we performed conditional Poisson regressions to generate incidence rate ratios (IRR) and 95% confidence intervals, with adjustment of patients' baseline covariates including age, sex, HBV, HCV and related medication. Of 54,267 RA patients and 137,889 AS patients identified between 2000 and 2015, 11,221 (20.7%) RA and 4,208 (3.1%) AS patients underwent TNFi therapy, with 722 (5%) receiving isoniazid for latent tuberculosis. We identified 31 incident cases (4.3%) of hospitalization due to severe hepatitis. Of these hospitalization events, 5 occurred in the exposed periods, 25 occurred in the INH unexposed periods, and 1 occurred in the pre-exposure period. Compared with non-exposure, the risk of severe hepatitis was higher in exposed periods (incidence rate ratio [IRR]: 5.1, 95% CI: 1.57-16.55), especially 57-84 days (IRR: 17.29, 95% CI: 3.11-96.25) and 85-168 days (IRR:10.55, 95% CI: 1.90-58.51). The INH related fatal hepatotoxicity was not identified in our study. Our findings suggest an association between risk of severe hepatitis and exposure to isoniazid in patients with RA or AS under TNFi therapy, particularly within the exposed period 57-168 days. A close monitoring of liver function is mandatory to minimize the risk, especially within the first 6 months after initiation of 9 months isoniazid.

Prevalence of latent tuberculosis in patients with hematological neoplasms in a cancer referral hospital in Mexico City.

OBJECTIVE: To determine the prevalence of Latent Tuberculosis in patients with hematological neoplasms at the Instituto Nacional de Cancerología in Mexico City using the Tuberculin skin test (TST). METHODS: This retrospective study included all patients with a recent diagnosis of hematological neoplasms who were admitted for treatment from 2017 to 2018 and who were screened for latent tuberculosis with the TST. The prevalence of latent tuberculosis in this group, tolerance and therapeutic adherence in treated patients are described. RESULTS: The files of 446 patients with hematological malignancy who had a TST were reviewed. The prevalence of latent tuberculosis was 31.2% (n = 139). Ninety-three patients received isoniazid, 15.1% had some adverse reactions, but only 4 (4.3%) had to discontinue treatment. Two patients with latent tuberculosis under treatment with Isoniazid reactivated tuberculosis infection. CONCLUSIONS: The prevalence in our study was within the range of other similar Mexican populations. Isoniazid treatment had an adequate tolerance and adherence. Longer follow-up could offer more information on the risk of reactivation in both groups.

Tuberculosis despite latent infection screening and treatment in patients receiving TNF inhibitor therapy.

INTRODUCTION: Although latent tuberculosis infection (LTBI) treatment is given before anti-tumor necrosis factor (TNF) treatment, tuberculosis (TB) still develops in these patients and the risk factors are not well known. Besides, there is little data on the safety of isoniazid (INH) treatment in this group of patients. This study aimed to determine the risk factors for the development of tuberculosis and the safety of LTBI in such patients. METHODS: All patients (n=665) given anti-TNF in a single center were included in this study. Complete data were obtained from the records of 389 patients. RESULTS: Seven patients (1.1%) were diagnosed with TB. There was no significant difference in age, gender, smoking rate, comorbidities, leukocyte counts, hemoglobin, creatinine, AST, ALT, protein levels, and tuberculin reaction between patients with and without TB. Of 389 patients, 289 (76%) had received INH prophylaxis, including 43 tuberculin-negative patients. Thirty patients had anti-TNF use prior to INH prophylaxis. None of these patients had TB in the follow-up period. Seven patients who developed TB had completed LTBI treatment, including one patient who was tuberculin-negative. The time from the completion of INH treatment to the diagnosis of TB was 6-61 months. None had any history of contact with TB during this period. INH treatment was associated with hepatotoxicity in 49 patients (17%); all resolved without any need to stop INH. CONCLUSION: Patients on anti-TNF treatment had a high rate of TB despite INH prophylaxis, but no risk factor for TB development was identified. Mild hepatotoxicity frequently developed during LTBI treatment. Key Points • Tuberculosis still develops in patients treated with tumor necrosis factor (TNF)-inhibitors despite prior screening and treatment for latent tuberculosis infection (LTBI). • In this cohort, all patients in whom tuberculosis developed had been treated for LTBI and all but one were initially tuberculin-positive. No risk factors have been identified. • The current policy of treating tuberculin-positive patients with a 9-month INH regimen does not seem to be fully effective in preventing tuberculosis.

Ameliorative potential of Adhatoda vasica against anti-tubercular drugs induced hepatic impairments in female Wistar rats in relation to oxidative stress and xeno-metabolism.

ETHNOPHARMACOLOGICAL RELEVANCE: Adhatoda vasica Nees is widely used herb of indigenous system to treat various ailments especially upper respiratory tract infections. Not only, anti-tubercular efficacy of crude extract and phytoconstituents of A. vasica has been documented but its hepatoprotective role against various drugs mediated hepatic alterations in different animal models has also been observed. BACKGROUND AND PURPOSE: Isoniazid, rifampicin and pyrazinamide (H-R-Z) are anti-tubercular drugs normally prescribed by health professionals for the treatment of tuberculosis, however along with their medical effectiveness these drugs also exhibit hepatotoxicity among TB patients. Unexpectedly, substantial toxicological data on the metabolism of anti-TB drugs are available but the mystery behind these xenobiotics is too complex and partly implicit. In this study, we further explored the hepatotoxic effects of these xeno-metabolic products and their amelioration by Adhatoda vasica Nees by elucidating its mechanistic action. METHODS: We generated a hepatotoxic rodent model by oral administration of H, R and Z (30.85, 61.7 and 132.65 mg/kg body weight) drugs for 25 days in Wistar rats. Additionally, to achieve hepatoprotection two different doses of Adhatoda vasica Nees ethanolic leaf extract (200 and 300 mg/kg body weight) were used along with H-R-Z dosage, orally and once daily for 25 days and tried to ascertain their mechanistic action. For this, initially phytoconstituents of the extract were evaluated followed by extract standardization using RP-HPLC and FTIR methods. Furthermore, antioxidant activity of the extract was analyzed by DPPH assay. Finally, different treated groups were analyzed for hepatic oxidative stress markers, antioxidant markers, histopathological changes and gene expression study including CYP2E1, CYP7A1, NAT, NR1I2 and UGT1A1 genes involved in phase I and phase II xeno-metabolism. RESULTS: Estimated content of vasicine in RP-HPLC method and free-radical scavenging activity in DPPH assay was found to be 134.519 ± 0.00269µg/10mg of leaf extract and 47.81 µg/mL respectively. In H-R-Z treated group, a significant increase in the levels of thiobarbituric acid, significant reduction in the levels of GSH, and enzymatic markers and marked changes in hepatic histological architecture were observed. In addition, there was significance up-regulation of CYP7A and NAT genes, down-regulation of CYP2E1 gene and insignificant expression levels of NR1I2 and UGT1A1 genes were observed in H-R-Z group. Conversely, high dose of A. vasica extract effectively diminished these alterations by declining oxidative stress and boosting of antioxidant levels. In addition, it acted as bi-functional inducer of both phase I (CYP2E1) and phase II (NAT and UGT1A1) enzyme systems. CONCLUSION: Hence, we concluded that anti-TB drugs exposure has potential to generate reactive metabolites that eventually cause hepatotoxicity by altering oxidant-antioxidant levels and their own metabolism. This study not only emphasized on xeno-metabolism mediated hepatic alterations but also explore the benefit of A. vasica on these toxic insults.

Pellagra a review exploring causes and mechanisms, including isoniazid-induced pellagra.

Pellagra is a clinical syndrome caused by a deficiency of niacin (nicotinic acid) and/or its precursor tryptophan. The cardinal manifestations are 4 D's: dermatitis, diarrhoea, dementia and in worst case death. Increased use of isoniazid prophylaxis along with antiretroviral therapy in countries where latent tuberculosis is common has been associated with increased presentations with pellagra.

Safety and Efficacy of Rifampin or Isoniazid Among People With Mycobacterium tuberculosis Infection and Living With Human Immunodeficiency Virus or Other Health Conditions: Post Hoc Analysis of 2 Randomized Trials.

BACKGROUND: The safety and efficacy of rifampin among people living with human immunodeficiency virus (PLHIV) or other health conditions is uncertain. We assessed completion, safety, and efficacy of 4 months of rifampin vs 9 months of isoniazid among PLHIV or other health conditions. METHODS: We conducted post hoc analysis of 2 randomized trials that included 6859 adult participants with Mycobacterium tuberculosis infection. Participants were randomized 1:1 to 10 mg/kg/d rifampin or 5 mg/kg/d isoniazid. We report completion, drug-related adverse events (AE), and active tuberculosis incidence among people living with HIV; with renal failure or receiving immunosuppressants; using drugs or with hepatitis; with diabetes mellitus; consuming >1 alcoholic drink per week or current/former smokers; and with no health condition. RESULTS: Overall, 270 (3.9%) people were living with HIV (135 receiving antiretroviral therapy), 2012 (29.3%) had another health condition, and 4577 (66.8%) had no condition. Rifampin was more often or similarly completed to isoniazid in all populations. AEs were less common with rifampin than isoniazid among PLHIV (risk difference, -2.1%; 95% confidence interval [CI], -5.9 to 1.6). This was consistent for others except people with renal failure or on immunosuppressants (2.1%; 95% CI, -7.2 to 11.3). Tuberculosis incidence was similar among people receiving rifampin or isoniazid. Among participants receiving rifampin living with HIV, incidence was comparable to those with no health condition (rate difference, 4.1 per 1000 person-years; 95% CI, -6.4 to 14.7). CONCLUSIONS: Rifampin appears to be safe and as effective as isoniazid across many populations with health conditions, including HIV. CLINICAL TRIALS REGISTRATION: NCT00170209; NCT00931736.

Ethambutol Induced Lichenoid Drug Eruption: A Case Report.

BACKGROUND: A rare type of cutaneous adverse drug reaction (CADR), lichenoid drug eruption (LDE), can be associated with ethambutol. CASE REPORT: A 60-year-old woman with spinal tuberculosis received multiple anti-TB medications and developed rashes after 3 months of the treatments. A skin biopsy from the posterior auricular area confirmed lichenoid dermatitis, and the Naranjo causality assessment indicated ethambutol as a probable cause of LDE in the patient. The rashes slowly improved after discontinuation of ethambutol. Unfortunately, the residual of brown hyperpigmentation on the body still persisted for over 16 months. CONCLUSION: The medications were reduced to isoniazid 300 mg/day and rifampicin 450 mg /day as planned for another 3 months. This case report points out the essentials of early recognition of ethambutol LDE by health care professionals.

Lipid peroxidation aggravates anti-tuberculosis drug-induced liver injury: Evidence of ferroptosis induction.

Anti-tuberculosis drug-induced liver injury (ATB-DILI) is a common adverse reaction of anti-tuberculosis drug treatment. Studies have shown that isoniazid (INH) and rifampicin (RFP) are mainly metabolized in the liver and a large amount of intracellular glutathione is used up during the metabolism of these drugs, resulting in lipid peroxidation and hepatocyte death. Ferroptosis is a novel form of programmed cell death caused by iron-ion-dependent lipid peroxidation. In this study, we explored lipid peroxidation and ferroptosis during ATB-DILI. Morphology of ferroptosis was discovered in ATB-DILI mouse livers by transmission electron microscopy. Flow cytometry was used to assess the molecular markers of lipid peroxidation and ferroptosis including reactive oxygen species, lipid peroxidation, and cellular iron content. Glutathione peroxidase 4 (GPX4) was depleted, while acyl-CoA synthetase long chain family member 4 (ACSL4) was overexpressed in the ATB-DILI tissues. And glutathione supplementation significantly reduced the level of lipid peroxidation and the risk of liver damage. Retrospective study of tuberculosis patients who underwent INH and RFP treatment also revealed an association between the intake of glutathione and a negative ATB-DILI rate. In addition, iron supplementation enhanced the degree of lipid peroxidation and liver injury induced by INH and RFP in vivo and clinical retrospective study. Taken together, these results indicate that lipid peroxidation and evidence suggestive of ferroptosis occurs during ATB-DILI, and glutathione replenishment prevents this process while iron supplementation augmenting this effect.

Isoniazid-induced gynaecomastia: report of a paediatric case and review of literature.

BACKGROUND: Gynaecomastia is a fairly common condition in puberty but is rare in prepubertal boys. While it is necessary to exclude possible endocrinopathay in prepubertal gynaecomastia, medication is an important and potentially reversible cause to consider in new onset gynaecomastia. Isoniazid-induced gynaecomastia has been reported in adult males, but none was reported in the paediatric population and general paediatricians may not be aware of this uncommon side effect. CASE PRESENTATION: We hereby report a 11-year-old prepubertal boy who developed gynaecomastia while taking anti-tuberculosis drugs. Investigations excluded endocrinopathies. Gynaecomastia subsided 8 weeks after stopping isoniazid. CONCLUSION: This case is the first paediatric case report describing the association of gynaecomastia with isoniazid use. It is important for general paediatricians to recognize this entity, as prompt diagnosis and cessation of the offending drug can lead to resolution of the problem.

Complication of Mycobacterium tuberculosis treatment: Isoniazid-induced pneumonitis.

Prolonged therapy with isoniazid is used for the treatment of pulmonary tuberculosis. Drug-induced lupus erythematosus is a rare, adverse event associated with isoniazid use and can complicate treatment, especially if it is associated with pneumonitis. The diagnosis is made by clinical suspicion, elevated serum titers of anti-nuclear antibody and anti-histone antibody, and new ground-glass opacities on chest tomography. Bronchoscopy with bronchoalveolar lavage and transbronchial biopsy of affected areas of the lung is useful to increase diagnostic accuracy and differentiate between drug-induced pneumonitis, concomitant infection, or other inflammatory processes. Treatment includes systemic corticosteroids and cessation of isoniazid therapy.

Chest roentgenography is complementary to interferon-gamma release assay in latent tuberculosis infection screening of rheumatic patients.

BACKGROUND: A study of latent tuberculosis infection (LTBI) burden by chest roentgenography (CXR) with reference to interferon-gamma release assay (IGRA) is still lacking in rheumatic patients of an intermediate tuberculosis burden area. METHODS: We retrospectively reviewed clinical data of patients with rheumatoid arthritis (RA), ankylosing spondylitis (AS), or psoriatic arthritis (PsA) receiving LTBI screening for biologics from Jan 2013 to April 2014. RESULTS: A total of 238 rheumatic patients who underwent LTBI screening were included in this study, of whom 46 (19.3%) had positive IGRA tests, 178 (74.8%) had negative results, and 14 (5.9%) had indeterminate results. Radiological findings suggesting healed tuberculosis (CXR-old-TB) were found in 18.1% of all patients, 23.9% in the IGRA -positive patients vs 16.9% in the IGRA-negative patients (OR 1.55 95% CI: 0.71-3.39, p = 0.27). Forty (40/46, 87.0%) IGRA-positive patients received isoniazid prophylaxis and 77.5% of them finished treatment. Six patients developed adverse effects of isoniazid treatment, resulting in an overall number needed to harm (NNH) of 6.7 (40/6). IGRA-non-positive patients with old TB-suggestive CXR comprised 13.4% (32/238) of all our rheumatic patients, and one of them developed pulmonary tuberculosis within one year after screening. CONCLUSIONS: LTBI disease burden in rheumatic patients is substantial according to the estimation of CXR and IGRA screening. Correlation between CXR and IGRA is not significant in rheumatic patients, which implies their complementary roles. IGRA-non-positive patients with old TB-suggestive CXR comprise a significant portion in rheumatic patients and merit cautious follow-up by rheumatologists, tuberculosis specialists, and pulmonologists.

[Lichenoid drug eruption with antituberculosis drugs associated with an anonychia]. / Toxidermie lichénoïde aux antituberculeux associée à une anonychie.

INTRODUCTION: Lichenoid cutaneous reactions to antituberculosis drugs are rare. Herein we report a new case. PATIENTS AND METHODS: A 41-year-old patient was seen for a profuse and pruriginous rash occurring 2 weeks after administration of rifampicin and isoniazid for pulmonary tuberculosis. Dermatological examination revealed polymorphic erythemato-squamous plaques with lichenoid, psoriatic and eczematous features, associated with cheilitis, erosions on the cheeks and diffuse onychodystrophy. The skin biopsy confirmed a lichenoid reaction. The pharmacovigilance investigation incriminated isoniazid and rifampicin. The patient was treated with topical corticosteroids and UVB phototherapy. The outcome involved complete regression of the eruption but with secondary anonychia. DISCUSSION: Antituberculosis drugs including isoniazid and rifampicin are known to induce lichenoid reactions. It is difficult to distinguish the results from lichen planus. The clinical polymorphism of the rash as well as the patient's drug intake militate in favour of a diagnosis of lichenoid reaction. Widespread ungual involvement, which is extremely rare, warranted early management in order to avert irreversible anonychia.

Influence of isoniazid on T lymphocytes, cytokines, and macrophages in rats

T lymphocytes, cytokines, and macrophages play important roles in the clearance of Mycobacterium tuberculosis (Mtb) by the immune system. This study aimed to investigate the effects of isoniazid on the functions of both innate and adaptive immune cells. Healthy rats were randomly divided into experimental and control groups. Each group was randomly divided into three subgroups and named according to the duration of drug feeding, 1, 3, and 3 months followed by drug withdrawal for 1 month. The experimental groups were fed with isoniazid (12 mg/mL) and the control groups with normal saline. The percentage of CD4+ and CD8+T lymphocytes, level of interleukin (IL)-12 and interferon (IFN)-γ, and function of macrophages were determined at these three time points. Isoniazid significantly increased the percentage of CD4+T lymphocytes and the CD4+/CD8+T lymphocyte cell ratio (P < 0.05). It transiently (<1 month) enhanced the functions of rat macrophages significantly (P < 0.05). In summary, isoniazid could increase the percentage of CD4+T lymphocytes, CD4+/CD8+T lymphocyte cell ratio, and enhance macrophage function in healthy rats