Ocular adverse events in drug sensitive TB patients on daily fixed dose combination anti-TB drugs: A record review study from Kerala, India

Abstract

BACKGROUND:Government of India's Revised National TB Control Programme (RNTCP) has begun implementing daily fixed dose combination (FDC) anti-TB treatment regimen for drug sensitive TB patients in which ethambutol is given for six months. Prolonged ethambutol use is known to cause ocular adverse drug events (ADE). OBJECTIVES:To assess the magnitude of ocular ADEs in adult drug sensitive TB patients initiated on daily FDCs and to describe the demographic and clinical profile of patients with ocular ADEs. METHODS:We conducted a retrospective cohort study involving review of RNTCP records of all adult (age >14 years) drug sensitive TB patients initiated on daily FDCs between1st January 2018 and 31st July 2018 in Thiruvananthapuram district, Kerala State, India. RESULTS:714 patients were initiated on daily FDCs during the study period. It was unknown whether all patients had undergone assessment for ocular ADEs. However, of these 714 patients, 8 patients (1.1%) were documented to have had ocular ADEs. Seven of these 8 patients had received ethambutol more than 15 mg/kg body weight and had developed ocular symptoms (decreased/blurring of vision) 3 months after TB treatment initiation. Ethambutol was stopped in all these 8 patients. In 5 patients it was recorded that ocular ADEs had resolved following stoppage of ethambutol and in the remaining it was unknown. CONCLUSION:The study confirms the occurrence of ocular ADEs among drug sensitive TB patients on daily FDCs and recommends strengthening of systems for assessing, documenting and managing ocular ADE.