Antitubercular Drugs

Which antitubercular drug is contraindicated in patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency due to risk of hemolytic anemia?

A 38-year-old man with newly diagnosed pulmonary tuberculosis is started on standard first-line therapy. He develops jaundice on day 15 of treatment. Which antitubercular drug is BEST distinguished from the others as the primary culprit based on its hepatotoxicity mechanism?

A 32-year-old man with newly diagnosed pulmonary tuberculosis is started on standard four-drug therapy (HRZE). After 2 weeks of treatment, he develops acute onset jaundice, dark urine, and right upper quadrant tenderness. Liver function tests show ALT 320 U/L, AST 380 U/L, total bilirubin 4.2 mg/dL, and alkaline phosphatase 95 U/L. Hepatitis A, B, and C serology are negative. What is the most appropriate next step in management?

Which feature BEST distinguishes isoniazid-induced peripheral neuropathy from rifampicin-induced drug interactions in tuberculosis treatment?

A 32-year-old woman from rural Maharashtra presents with a 3-month history of productive cough, fever, and weight loss. Chest X-ray shows cavitary lesions in the right upper lobe. Sputum smear microscopy is positive for acid-fast bacilli. She is started on standard first-line antitubercular therapy (RIPE: rifampicin, isoniazid, pyrazinamide, ethambutol). After 2 weeks of therapy, she develops acute-onset red discoloration of urine and tears, along with mild jaundice. Liver function tests show: AST 120 U/L, ALT 95 U/L, total bilirubin 2.8 mg/dL. Which drug is most likely responsible for these adverse effects?