Intestinal obstruction following antituberculosis therapy in a patient with pancreatic carcinoma and pulmonary tuberculosis: a case report.

INTRODUCTION: Intestinal obstruction is a common complication in patients with advanced malignancies, often attributed to the disease itself or as a side effect of opioid analgesics used for pain management. However, the occurrence of intestinal obstruction following antituberculosis therapy is rare. CASE PRESENTATION: We report a unique case of a 58-year-old Asian male diagnosed with stage IV pancreatic carcinoma and pulmonary tuberculosis. The patient was initiated on a regimen of ethambutol hydrochloride, pyrazinamide, rifampicin, and isoniazid tablets (II) for tuberculosis, alongside morphine for the management of severe cancer-related pain. Subsequently, he developed symptoms indicative of intestinal obstruction. Despite discontinuation of morphine, the patient's symptoms persisted until he autonomously ceased all medications, leading to a rapid improvement in his condition. This unexpected resolution highlighted the antituberculosis drugs as the probable cause of his intestinal obstruction. CONCLUSIONS: This case underscores the importance of considering antituberculosis drugs as a potential cause of intestinal obstruction, especially in patients who do not respond to conventional management strategies for drug-induced gastrointestinal side effects. It also emphasizes the need for heightened vigilance and monitoring when prescribing these medications to patients with advanced malignancies, to promptly identify and address rare but significant side effects.

Differential distribution of NAT2 polymorphisms and NAT2 acetylator phenotypes among indigenous populations of the Brazilian Amazon.

OBJECTIVES: We report, for the first time, the distribution of four no-function NAT2 single nucleotide polymorphisms and inferred NAT2 acetylator phenotypes in three indigenous groups (Munduruku, Paiter-Suruí, and Yanomami), living in reservation areas in the Brazilian Amazon. METHODS: Two hundred and seventy-six participants from three indigenous groups (92 for each group) were included and genotyped for four NAT2 polymorphisms (rs1801279, rs1801280, rs1799930, and rs1799931) by the TaqMan system. Minor Allele Frequency (MAF) was determined and NAT2 acetylator phenotypes were inferred. RESULTS: NAT2 rs1801279G>A was absent in all cohorts; rs1799930G>A was absent in Yanomami and rare (MAF 0.016) in Munduruku and Paiter-Suruí; MAF of rs1801280T>C ranged five-fold (0.092-0.433), and MAF of rs1799931G>A varied between 0.179 and 0.283, among the three groups. The distribution of NAT2 phenotypes differed significantly across cohorts; the prevalence of the slow acetylator phenotype ranged from 16.3% in Yanomami to 33.3% in Munduruku to 48.9% in Paiter-Suruí. This three-fold range of variation is of major clinical relevance because the NAT2 slow phenotype is associated with higher risk of hepatotoxicity with antituberculosis chemotherapy and high incidence rates of tuberculosis and burden of latent infection among Munduruku, Paiter-Surui, and Yanomami peoples. According to the frequency of the NAT2 slow acetylator phenotype, the estimated number of individuals needed to be genotyped to prevent one additional event of hepatotoxicity range from 31 (Munduruku) to 39 (Paiter-Surui) and to 67 (Yanomami). CONCLUSION: The rs1801279 polymorphism was not found in any of the cohorts, while the MAF of the other polymorphisms showed significant variation between the cohorts. The difference in the prevalence of the NAT2 slow acetylator phenotype, which is linked to isoniazid-induced hepatotoxicity, was observed in the different study cohorts.

Diagnosis, prevention and risk-management of drug-induced liver injury due to medications used to treat mycobacterium tuberculosis.

INTRODUCTION: Many of the first line medications for the treatment of active and latent M. tuberculosis are hepatoxic and cause a spectrum of anti-tuberculosis drug induced liver injury (ATLI), including acute liver failure (ALF). Despite advances in recognition of and prevention of ATLI, isoniazid remains one of the leading causes of DILI as well as drug-induced ALF. AREAS COVERED: A literature search of the incidence, risk factors, current societal guidelines, monitoring, and prophylactic medication usage in ATLI was performed using PubMed and institutional websites. Relevant articles from 1972 to 2024 were included in this review. EXPERT OPINION: Current societal guidelines regarding ATLI monitoring are mixed, but many recommend liver enzyme testing of high-risk populations. We recommend liver test monitoring for all patients on multi-drug therapy as well as those on isoniazid therapy. Precision medicine practices, such as N-acetyltransferase-2 polymorphism genotyping, are thought to be beneficial in reducing the incidence of ATLI in high-risk populations. However, broader implementation is currently cost prohibitive. Hepatoprotective drugs are not currently recommended, although we do recognize their potential. In patients who develop ATLI but require ongoing anti-TB treatment, strategies to restart the same or less hepatotoxic regimens are currently being followed.

Characteristics of isoniazid-induced psychosis: a systematic review of case reports and case series.

PURPOSE: Isoniazid, a first-line antitubercular drug, is associated with nervous system adverse drug reactions such as seizures, peripheral neuropathy, and psychosis. This systematic review of case reports and case series aimed to characterize the demographic, social, and clinical factors associated with isoniazid-induced psychosis in patients with active tuberculosis (TB) and those who received isoniazid for latent TB infection (LTBI). METHODS: We comprehensively searched the Embase, PubMed, and Scopus databases to identify relevant studies published between the date of inception of the database and June 2024. RESULTS: A total of 28 studies, including 21 case reports and 7 case series involved 37 patients who developed isoniazid-induced psychosis. A higher frequency of isoniazid-induced psychosis was observed during the first 2 months of treatment, with a relatively early onset observed among patients aged 18 years or less. Delusions and/or hallucinations are the common symptoms of isoniazid-induced psychosis. Psychomotor disturbances, disorganized speech or formal thought disorder, disorganized or abnormal behaviour, and neuropsychiatric symptoms (sleep disturbances, hostility or aggression, confusion, affective symptoms, anxiety symptoms, and cognitive difficulties) were the other symptoms observed in the included studies. More than 80% of cases rechallenged with isoniazid resulted in the recurrence of psychotic symptoms. CONCLUSION: Patients with TB and LTBI should be assessed for psychotic and neuropsychiatric symptoms during isoniazid therapy, mainly in the first 2 months. Further research is required to understand the impact of underlying risk factors, such as genetic predisposition and isoniazid pharmacokinetics, as well as the clinical utility and dosage recommendations of pyridoxine for managing isoniazid-induced psychosis.

Precision Medicine Strategies to Improve Isoniazid Therapy in Patients with Tuberculosis.

Due to interindividual variability in drug metabolism and pharmacokinetics, traditional isoniazid fixed-dose regimens may lead to suboptimal or toxic isoniazid concentrations in the plasma of patients with tuberculosis, contributing to adverse drug reactions, therapeutic failure, or the development of drug resistance. Achieving precision therapy for isoniazid requires a multifaceted approach that could integrate various clinical and genomic factors to tailor the isoniazid dose to individual patient characteristics. This includes leveraging molecular diagnostics to perform the comprehensive profiling of host pharmacogenomics to determine how it affects isoniazid metabolism, such as its metabolism by N-acetyltransferase 2 (NAT2), and studying drug-resistant mutations in the Mycobacterium tuberculosis genome for enabling targeted therapy selection. Several other molecular signatures identified from the host pharmacogenomics as well as other omics-based approaches such as gut microbiome, epigenomic, proteomic, metabolomic, and lipidomic approaches have provided mechanistic explanations for isoniazid pharmacokinetic variability and/or adverse drug reactions and thereby may facilitate precision therapy of isoniazid, though further validations in larger and diverse populations with tuberculosis are required for clinical applications. Therapeutic drug monitoring and population pharmacokinetic approaches allow for the adjustment of isoniazid dosages based on patient-specific pharmacokinetic profiles, optimizing drug exposure while minimizing toxicity and the risk of resistance. Current evidence has shown that with the integration of the host pharmacogenomics-particularly NAT2 and Mycobacterium tuberculosis genomics data along with isoniazid pharmacokinetic concentrations in the blood and patient factors such as anthropometric measurements, comorbidities, and type and timing of food administered-precision therapy approaches in isoniazid therapy can be tailored to the specific characteristics of both the host and the pathogen for improving tuberculosis treatment outcomes.

A Case of Scrofuloderma in a Patient on JAK Inhibitor Treatment for Rheumatoid Arthritis.

A 78-year-old woman with rheumatoid arthritis, who was started on baricitinib five or six months earlier, was referred to our hospital due to a subcutaneous abscess in her right axilla. Contrast-enhanced chest, abdomen, and pelvis computed tomography showed subcutaneous abscesses in her right axilla and lymphadenopathy with calcification. Cultures from the subcutaneous abscess and skin biopsy specimens were positive for Mycobacterium tuberculosis. These findings led to the diagnosis of scrofuloderma associated with tuberculous lymphadenitis. She was started on an antitubercular regimen of isoniazid, rifampicin, pyrazinamide, and ethambutol as the initial phase treatment (first 2 months), followed by isoniazid and rifampicin for 4 months (total 6 months). After 6 months of antitubercular treatment, the abscesses and lymphadenitis disappeared. Although cases of tuberculosis during JAK inhibitor treatment are rare, they are serious adverse events that require caution.

One-month daily and three-month weekly rifapentine plus isoniazid are comparable in completion rate and safety for latent tuberculosis infection in non-HIV Population: a randomized controlled trial.

OBJECTIVES: The weekly rifapentine plus isoniazid for 3 months (3HP) improves completion rate of latent tuberculosis infection treatment, but flu-like symptoms are common. The novel 1HP regimen, involving daily rifapentine plus isoniazid for 28 days, has demonstrated low toxicity in HIV-infected populations. We aimed to investigate whether 1HP has a lower incidence rate of systemic drug reaction (SDR) compared with 3HP during treatment in non-HIV populations. METHODS: This randomized, multicentre trial compared the completion rate and risks of SDRs of 1HP and 3HP in aged ≥13 years non-HIV subjects with latent tuberculosis infection between September 2019 and September 2023 (ClinicalTrials.gov: NCT04094012). We also investigated associations between SDRs and plasma levels of drugs and their metabolites. RESULTS: A total of 251 and 239 individuals were randomly assigned to 1HP and 3HP groups, respectively, with completion rates of 82.9% (208/251) and 84.5% (202/239), respectively. Among them, 12.7% (32/251) and 10.9% (26/239) of 1HP and 3HP groups experienced SDRs, respectively (p 0.522), predominantly urticaria in 1HP group (59.4% [19/32]) and flu-like syndrome in 3HP group (80.8% [21/26]). Among participants experiencing SDRs, 43.8% (14/32) and 34.6% (9/26) in 1HP and 3HP groups, respectively, completed treatment (p 0.470). Cutaneous reactions were more common in 1HP than 3HP group (32.7% [82/251] vs. 13.0% [31/239], p < 0.001). In 1HP group, urticaria was associated with a higher plasma desacetyl-rifapentine level (ug/mL) at both 2 (median [interquartile range]: 36.06 [17.46-50.79] vs. 22.94 [14.67-31.65], p 0.018) and 6 hours (26.13 [15.80-53.06] vs. 29.83 [18.13-34.01], p 0.047) after dosing. DISCUSSION: In non-HIV population, the incidence rate of SDR under 1HP is not lower than 3HP. Notably, urticaria, rather than flu-like syndrome, was the predominant SDR associated 1HP. The findings of this study underscore the feasibility of 1HP regimen in non-HIV populations with a high-completion rate exceeding 80%.

Efficacy and tolerability of a 4-month ofloxacin-containing regimen compared to a 6-month regimen in the treatment of patients with superficial lymph node tuberculosis: a randomized trial.

BACKGROUND: Tuberculosis (TB) lymphadenitis is the most common form of extra-pulmonary TB, and the treatment duration is six months. This non-inferiority based randomized clinical trial in South India evaluated the efficacy and safety of a four-month ofloxacin containing regimen in tuberculosis lymphadenitis (TBL) patients. METHODS: New, adult, HIV-negative, microbiologically and or histopathologically confirmed superficial lymph node TB patients were randomized to either four-month oflaxacin containing test regimen [ofloxacin (O), isoniazid (H), rifampicin (R), pyrazinamide (Z) -2RHZO daily/ 2RHO thrice-weekly] or a six-month thrice-weekly control regimen (2HRZ, ethambutol/4RH). The treatment was directly observed. Clinical progress was monitored monthly during and up to 12 months post-treatment, and thereafter every three months up to 24 months. The primary outcome was determined by response at the end of treatment and TB recurrence during the 24 months post-treatment. RESULTS: Of the 302 patients randomized, 298 (98.7%) were eligible for modified intention-to-treat (ITT) analysis and 294 (97%) for per-protocol (PP) analysis. The TB recurrence-free favourable response in the PP analysis was 94.0% (95% CI: 90.1-97.8) and 94.5% (95% CI: 90.8-98.2) in the test and control regimen respectively, while in the ITT analysis, it was 92.7% and 93.2%. The TB recurrence-free favourable response in the test regimen was non-inferior to the control regimen 0.5% (95% CI: -4.8-5.9) in the PP analysis based on the 6% non-inferiority margin. Treatment was modified for drug toxicity in two patients in the test regimen, while one patient had a paradoxical reaction. CONCLUSION: The 4-month ofloxacin containing regimen was found to be non-inferior and as safe as the 6-month thrice-weekly control regimen.

[Efficacy and safety of first-line anti-tuberculosis drugs combined with Linezolid for the treatment of pediatric tuberculous meningitis in real-word practice].

Objective: To evaluate the efficacy and safety of first-line anti-tuberculosis (TB) drugs combined with linezolid in treatment of children with tuberculous meningitis (TBM). Methods: A retrospective cohort study design was performed. Eight-nine Children diagnosed as TBM during January 1st 2016 and December 31st 2023 in Department of Infectious Disease, Children's Hospital of Chongqing Medical University were enrolled in the study. According to different treatment regimens, children were divided into a group of first-line anti-tuberculous drugs (isoniazid, rifampicin, pyrazinamide, ethambutol (HRZE)) and a group of HRZE and linezolid combination (HRZEL). The efficacy and safety of the 2 regimens were compared and the relationship between linezolid drug concentration and adverse reactions were analyzed. Comparisons between groups were performed using χ2 test and Mann-Whitney U test. Results: The 89 children with TBM included 53 males and 36 females with an onset age of 4.6 (1.4, 9.6) years. There were 27 cases in the HZREL group and 62 cases in the HRZE group. Before treatment, positive rate of interferon-gamma release assays (IGRA) in HRZEL group was lower than that in HRZE group (64% (16/25) vs.92% (55/60), χ2=9.82, P<0.05), but protein level of cerebrospinal fluid (CSF) was higher than that in HRZE group (1.2 (1.0, 2.0) vs.0.8 (0.4,1.4) g/L, Z=0.32, P<0.05). By the end of the intensive phase, there were no significant differences of rates of CSF improvement and etiology negativity between HRZEL group and HRZE group (both P>0.05).The 44 TBM children with high CSF protein (>1 g/L) included 25 males and 19 females with an onset age of 6.7 (3.0, 11.8) years. There were 21 cases in the HZREL group and 23 cases in the HRZE group accordingly. Before treatment, there were no significant differences of positive rate of IGRA test and CSF protein level between the 2 groups (62% (13/21) vs. 87% (20/23), 1.7 (1.1, 2.2) vs. 1.5 (1.2, 1.9) g/L, χ2=3.67, Z=0.23, both P>0.05). There were no significant differences in CSF indicators, etiology negativity or imaging remission between the two groups by the end of intensive phase (all P>0.05). Higher frequencies of granulocytopenia, gastrointestinal symptoms as well as withdrawal or change of drugs were found in HRZEL group when compared to those in HRZE group (44% (12/27) vs. 19% (12/62), 7% (2/27) vs. 0, 33% (9/27) vs. 3% (2/62), χ2=6.01, 4.70, 15.74, all P<0.05). Conclusions: The efficacy of HRZEL regimen is similar to conventional HRZE regimen in children with TBM, but with higher adverse effect. Prudentially evaluating the pros and cons of linezolid in the usage of drug-susceptible TB and carefully monitoring of linezolid associated adverse effects is suggested.

Study of adverse drug reactions during the treatment of drug resistant tuberculosis.

BACKGROUND: Pharmacovigilance entails monitoring of patients for timely detection of ADR and reporting them so that more information about drug safety can be obtained. This may help in the future for dose modification or alteration of regimen. In NTEP, ADSm (Active Drug Safety monitoring) is part of pharmacovigilance. In this study we shall be studying ADRs to Anti TB drugs in DRTB. METHODOLOGY: This study is observational, retrospective and record based, of patients admitted from 2021 to 2023 in the DOTS ward of Respiratory Medicine Department of a tertiary care hospital in Goa. Data such as age, sex, regimen, date of AKT initiation and adverse effects documented has been noted and compiled. RESULTS: ADRs have been tabulated in the form of tables. Statistical analysis is done to find out the commonest ADR, time when they are likely to occur, which age and gender are most likely affected and if there are any other associated risk factors for ADRs. CONCLUSION: This study will enable in future to better monitor patients with regard to particular adverse drug reaction, patient safety and if needed to alter the regimen as early as possible.

The Unusual Adverse Effects of Antituberculosis Therapy in Kidney Patients.

BACKGROUND: Chronic kidney disease (CKD) patients are at a high risk of tuberculosis (TB), with a relative risk of developing active TB of 10%-25%. Similarly, glomerular disease increases the risk of TB due to diminished glomerular filtration rate, proteinuria, and immunosuppression use. Further, the first-line anti-TB drugs are associated with acute kidney injury (AKI) even in patients with normal kidney functions. METHODS: We retrospectively identified 10 patients hospitalized with unusual adverse effects of antituberculosis therapy (ATT) from 2013 to 2022. RESULTS: We found three cases of AKI caused by rifampicin: acute interstitial nephritis, crescentic glomerulonephritis, and heme pigment-induced acute tubular necrosis. We observed rifampicin-induced accelerated hypertension and thrombocytopenia in two patients on maintenance hemodialysis. Isoniazid caused pancreatitis and cerebellitis in two CKD patients, respectively. In a CKD patient, we detected acute gout secondary to pyrazinamide-induced reduced uric acid excretion. We also observed cases of drug rash with eosinophilia and systemic symptoms and hypercalcemia due to immune reconstitution inflammatory syndrome in patients with glomerular disease on ATT. Immediate discontinuation of the offending drug, along with specific and supportive management, led to a recovery in all cases. CONCLUSION: The adverse effects of ATT may be unusually severe and varied in kidney patients due to decreased renal elimination. Early recognition of these adverse effects and timely discontinuation of the offending drug is essential to limit morbidity and mortality.

Isoniazid-induced pancreatitis: A systematic review.

BACKGROUND: Isoniazid-induced pancreatitis is a potentially serious adverse drug reaction, however, the frequency of its occurrence is unknown. We conducted a systematic review to explore this adverse drug reaction comprehensively. METHODS: We performed an advanced search in PubMed, Web of Science, Scopus, Ovid, and Embase for studies that reported isoniazid-induced pancreatitis. From the extracted data of eligible cases, we performed a descriptive analysis and a methodological risk of bias assessment using a standardized tool. RESULTS: We included 16 case reports from eight countries comprising 16 patients in our systematic review. Most of the isoniazid-induced pancreatitis cases were extrapulmonary tuberculosis cases. We found the mean age across all case reports was 36.7 years. In all the cases, discontinuation of isoniazid resulted in the resolution of pancreatitis. CONCLUSIONS: We found the latency period for isoniazid-induced pancreatitis to be ranged from 12 to 45 days after initiation of isoniazid therapy. A low threshold for screening of pancreatitis by measuring pancreatic enzymes in patients on isoniazid presenting with acute abdominal pain is recommended. This would facilitate an early diagnosis and discontinuation of isoniazid, thus reducing the severity of pancreatitis and preventing the complications of pancreatitis.

Efficacy and safety of intrathecal dexamethasone combined with isoniazid in the treatment of tuberculous meningitis: a meta-analysis.

BACKGROUND: The treatment regimen for tuberculous meningitis (TBM) remains unclear and requires optimization. There are some reports on successful adjunct intrathecal dexamethasone and isoniazid (IDI) treatment strategies for TBM, however, there is equivocal evidence on their efficacy and safety. METHODS: A comprehensive search of English and Chinese databases was conducted from inception to February 2024. A meta-analysis was performed on randomized controlled trials (RCTs) estimating the effects of adjunct IDI on conventional anti-TB (C anti-TB) treatments or C anti-TB alone. Efficacy, adverse reaction rate, cerebrospinal fluid (CSF) leukocytes, and CSF protein were used as primary outcome indicators. CSF glucose, CSF chlorides, CSF pressure, recovery time for laboratory indicators and recovery time for clinical symptoms were used as secondary outcome indicators. RESULTS: A total of 17 studies involving 1360 (IDI group vs. C anti-TB group: 392 vs. 372; higher-dose IDI group vs. lower-dose IDI group: 319 vs. 277) patients were included in our analysis. Efficacy was significantly higher (RR 1.3, 95% CI 1.2-1.4, P < 0.001) and adverse reaction rate was significantly lower in the IDI groups (RR 0.59, 95% CI 0.37-0.92, P = 0.021). Furthermore, CSF leukocytes (WMD - 29.33, 95% CI [- 40.64 to-18.02], P < 0.001) and CSF protein (WMD - 0.79, 95%CI [-0.96 to-0.61], P < 0.001) were significantly lower in the IDI groups. Recovery time indicators were all shorter in the IDI groups, fever (SMD - 2.45, 95% CI [-3.55 to-1.35], P < 0.001), coma (SMD-3.75, 95% CI [-4.33 to-3.17], P < 0.001), and headache (SMD  - 3.06, 95% CI [- 4.05 to-2.07], P < 0.001), respectively. Higher-dose IDI was more effective than lower-dose IDI (RR 1.23, 95% CI 1.14-1.33, P < 0.001), with no significant difference in adverse reaction rate between the two (RR 0.82, 95%CI 0.43-1.56, P = 0.544). CONCLUSION: Adjunct IDI with C anti-TB can enhance therapeutic outcomes and reduce adverse reaction rate in adult TBM patients, with higher-dose IDI showing superior efficacy. These findings highlight the potential of IDI as an adjunctive therapy in TBM management. However, more high-quality RCTs from more regions should be conducted to support our results. TRIAL REGISTRATION: Retrospectively registered in PROSPERO  https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023388860 .

Efficacy, safety, and pharmacokinetics of isoniazid affected by NAT2 polymorphisms in patients with tuberculosis: A systematic review.

N-acetyltransferase 2 (NAT2) genetic polymorphisms might alter isoniazid metabolism leading to toxicity. We reviewed the impact of NAT2 genotype status on the pharmacokinetics, efficacy, and safety of isoniazid, a treatment for tuberculosis (TB). A systematic search for research articles published in Scopus, PubMed, and Embase until August 31, 2023, was conducted without filters or limits on the following search terms and Boolean operators: "isoniazid" AND "NAT2." Studies were selected if NAT2 phenotypes with pharmacokinetics or efficacy or safety of isoniazid in patients with TB were reported. Patient characteristics, NAT2 status, isoniazid pharmacokinetic parameters, early treatment failure, and the prevalence of drug-induced liver injury were extracted. If the data were given as a median, these values were standardized to the mean. Forty-one pharmacokinetics and 53 safety studies were included, but only one efficacy study was identified. The average maximum concentrations of isoniazid were expressed as supratherapeutic concentrations in adults (7.16 ± 4.85 µg/mL) and children (6.43 ± 3.87 µg/mL) in slow acetylators. The mean prevalence of drug-induced liver injury was 36.23 ± 19.84 in slow acetylators, which was significantly different from the intermediate (19.49 ± 18.20) and rapid (20.47 ± 20.68) acetylators. Subgroup analysis by continent showed that the highest mean drug-induced liver injury prevalence was in Asian slow acetylators (42.83 ± 27.61). The incidence of early treatment failure was decreased by genotype-guided isoniazid dosing in one study. Traditional weight-based dosing of isoniazid in most children and adults yielded therapeutic isoniazid levels (except for slow acetylators). Drug-induced liver injury was more commonly observed in slow acetylators. Genotype-guided dosing may prevent early treatment failure.

Drug-Induced Liver Injury in Pregnancy: The U.S. Drug-Induced Liver Injury Network Experience.

There are limited data on the causative agents and characteristics of drug-induced liver injury in pregnant individuals. Data from patients with drug-induced liver injury enrolled in the ongoing multicenter Drug-Induced Liver Injury Network between 2004 and 2022 and occurring during pregnancy or 6 months postpartum were reviewed and compared with cases of drug-induced liver injury in nonpregnant women of childbearing age. Among 325 individuals of childbearing age in the Drug-Induced Liver Injury Network, 16 cases of drug-induced liver injury (5%) occurred during pregnancy or postpartum. Compared with drug-induced liver injury in nonpregnant women, pregnancy-related drug-induced liver injury was more severe ( P <.05). One elective termination and three miscarriages were documented; there were no maternal deaths. We recommend that isoniazid for latent tuberculosis be deferred to the postpartum period whenever feasible and that ß-blockers or calcium channel blockers rather than methyldopa be used for hypertension management during pregnancy.

Pharmacogenetic variability of tuberculosis biomarkers in native and mestizo Peruvian populations.

In Peru, 29 292 people were diagnosed with tuberculosis in 2022. Although tuberculosis treatments are effective, 3.4%-13% are associated with significant adverse drug reactions, with drug-induced liver injury (DILI) considered the most predominant. Among the first-line antituberculosis drugs, isoniazid is the main drug responsible for the appearance of DILI. In liver, isoniazid (INH) is metabolized by N-acetyltransferase-2 (NAT2) and cytochrome P450 2E1 (CYP2E1). Limited information exists on genetic risk factors associated with the presence of DILI to antituberculosis drugs in Latin America, and even less is known about these factors in the native and mestizo Peruvian population. The aim of this study was to determine the prevalence of NAT2 and CYP2E1 genotypes in native and mestizo population. An analytical cross-sectional analysis was performed using genetic data from mestizo population in Lima and native participants from south of Peru. NAT2 metabolizer was determined as fast, intermediate and slow, and CYP2E1 genotypes were classified as c1/c1, c1/c2 and c2/c2, from molecular tests and bioinformatic analyses. Of the 472 participants, 36 and 6 NAT2 haplotypes were identified in the mestizo and native population, respectively. In mestizo population, the most frequent NAT2*5B and NAT2*7B haplotypes were associated with DILI risk; while in natives, NAT2*5G and NAT2*13A haplotypes were associated with decreased risk of DILI. For CYP2E1, c1/c1 and c1/c2 genotypes are the most frequent in natives and mestizos, respectively. The linkage disequilibrium of NAT2 single nucleotide polymorphisms (SNPs) was estimated, detecting a block between all SNPs natives. In addition, a block between rs1801280 and rs1799929 for NAT2 was detected in mestizos. Despite the limitations of a secondary study, it was possible to report associations between NAT2 and CYP2E alleles with Peruvian native and mestizo by prevalence ratios. The results of this study will help the development of new therapeutic strategies for a Tuberculosis efficient control between populations.

Topical isoniazid as a novel treatment for melasma: A randomized, double-blind, vehicle-controlled clinical trial.

INTRODUCTION: Melasma is a chronic hyperpigmentation disorder, and its treatment poses a challenge to dermatologists due to its chronicity and resistance to conventional therapies. Oral isoniazid is used for the treatment of tuberculosis. One of us had previously showed that topical isoniazid exerts a strong depigmenting action in animal models. In this clinical trial, we assessed the therapeutic effect of topical isoniazid on melasma. METHODS: Twenty female patients suffering from epidermal melasma were enrolled and divided equally into two groups. The treatment group received topical isoniazid 10%, and the control group received the cold cream vehicle as the placebo. All participants were advised to avoid sunlight and used SPF 50 sunscreen. Patients applied topical agents once daily at night for 3 months. The melanin and erythema indices were measured by colorimetric evaluations at baseline and after 4, 8, and 12 weeks of treatment. At these time points, the (mMASI) score was also determined, as was the subjective evaluation through Melasma Quality of Life Scale (MELASQOL) scores. Blood tests were performed to evaluate CBC and the liver enzymes. RESULTS: All patients completed the 12-week study. In the treatment group, a significant decrease in melanin index from 63.77 ± 6.27 at baseline to 55.92 ± 5.79 was recorded (p = 0.001). Very minimal clinical changes were also seen in the control group and melanin index was decreased from 62.65 ± 2.23 to 61.25 ± 2.34 (p = 0.004). Clinically significant differences were observed in the rate of changes between both groups. These findings indicate that topical isoniazid has significant depigmenting effects compared to the placebo (p = 0.001). The erythema index remained unchanged in both groups. In the treatment group, the mMASI score was 5.63 ± 3.28 at baseline and 2.13 ± 1.71 at the last follow-up, significantly reduced compared to the control group (p = 0.002). The MELASQOL score indicated a significant improvement in the quality of life in the treatment group. CONCLUSION: This clinical trial shows for the first time that topical isoniazid is effective in treating melasma. Further clinical trials are necessary to confirm the efficacy and tolerability of topical isoniazid in comparison with other skin-depigmenting compounds.

Isoniazid use, effectiveness, and safety for treatment of latent tuberculosis infection: a systematic review.

BACKGROUND: The treatment strategy for latent tuberculosis infection is to reduce the number of tuberculosis cases and consequently reduce the transmission of pathogenic bacteria. This study aimed to determine the safety, effectiveness, and adherence of isoniazid use for latent tuberculosis infection treatment. METHODS: To identify studies on isoniazid use for latent tuberculosis infection, five electronic databases were searched. The methods and results are presented in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. RESULTS: Most studies (53) used isoniazid for 9 months. The prevalence of use and adherence to treatment varied considerably (18% to 100%), and were evaluated by participant completion of isoniazid treatment for latent tuberculosis infection. The adverse events most frequently reported were hepatotoxicity, gastric intolerance, and neuropathy; the rates of occurrence ranged from < 1% to 48%. In the studies that evaluated the effectiveness of isoniazid for latent tuberculosis infection, the rate varied from 0 to 19.7% for patients who did not have active tuberculosis after the follow-up period. CONCLUSIONS: The importance of maintaining follow up for patients using isoniazid should be emphasized due to the risk of developing adverse events. Despite the treatment challenges, the rates of patients who used isoniazid and developed active tuberculosis during the follow-up period were low. We believe that isoniazid continues to contribute to tuberculosis control worldwide, and better care strategies are required.