Epidemiology and Outcomes of Previously Treated Tuberculosis Patients at the Korle-Bu Teaching Hospital Chest Clinic in Accra, Ghana: A 6-Year Retrospective Review

Abstract

Background. Previously treated tuberculosis (TB) patients have a higher risk of drug resistance disease which may adversely affect treatment outcome. TB retreatment patients (RTP) include those deemed to be cured and present with recurrent TB (relapsed), or remained smear positive at the end of the fifth month of therapy (failed) or were lost to follow up (defaulted) during their initial treatment. Based on WHO guidelines, RTP have for many years been given a standardized five-drug Category II regimen (2SHRZE/1HRZE/5HRE). However, with increasing rates of resistance reported particularly to streptomycin, this regimen may be inadequate. This is the first study to review treatment outcomes of RTP in Ghana. Methods. A retrospective review of all patients with smear/culture-positive previously treated TB diagnosed between January 2010 and July 2015 at Korle-Bu Teaching Hospital Chest Clinic in Accra, Ghana. Descriptive statistics were used to summarize RTP characteristics and outcomes. Results. Two hundred sixteen smear/culture-positive RTP were identified, of which 75% were male and 18% were HIV positive. DST was available in 47 (21.8%) of RTP. MDR was identified in 19.1% of those with available DST, with streptomycin resistance seen in 21.3% and ethambutol resistance in 25.5%. Resistance was highest to isoniazid (48.9% in cultured retreatment patients, but 88.9% resistance seen the failed group). 86.3% of RTP were treated with the unmodified category 2. Mean length of therapy, regardless of treatment outcome was 6.9 months. Treatment success was achieved in 58.8% of RTP overall, with 6.5% failure and 14.8% all-cause mortality prior to the end of the prescribed treatment course. Relapse was documented in 10.9% of patients. The treatment success rate was 60.2%, 58.1% and 56.0% among RTP with relapse, initial treatment failure and defaulters, respectively. Conclusion(s) The overall treatment success rate of Category II regimen among RTP treated at a tertiary hospital clinic in Ghana was poor irrespective of disease classification. This is especially concerning given the high rates of first line drug resistance seen among those who had DST. There is an urgent need for the use of DST testing among all RTP at diagnosis in order to target therapy and improve outcomes.