Objective: To measure the impact on patient adherence to directly observed ambulatory tuberculosis treatment substituting an all-oral treatment regimen for a regimen containing streptomycin.
Methods: The expected and observed attendance of patients during the intensive phase of anti-tuberculosis treatment was measured daily at two out-patient clinics in Dar es Salaam. During the observation period, treatment was changed from a regimen containing streptomycin to an all-oral regimen, and attendance proportions were compared for the three periods during which patients always, sometimes or never received streptomycin during the intensive phase of treatment.
Results: In Kinondoni, an average of 98 patients was expected every day, in Ilala 127. No significant difference was observed in attendance in Kinondoni between periods when patients always (median attendance 95.9%) and never (median 95.7%) received streptomycin injections as part of their intensive phase treatment for tuberculosis. In Ilala, no difference was noted in attendance between the period in which patients received streptomycin for at least part of their treatment (median 91.3%) and the period when ethambutol had fully replaced streptomycin (median 91.8%).
Conclusions: In these two districts of Dar es Salaam, patient adherence to a completely oral treatment regimen was indistinguishable from that to a streptomycin-containing regimen. Given the potential of iatrogenic transmission of HIV and the advantages in reduced staff time and drug costs, the results clearly justify the replacement of streptomycin with ethambutol in Tanzania for new patients receiving an ambulatory rifampicin-containing regimen.
PIP: In a comparative study conducted among outpatients at tuberculosis clinics in the Ilala and Kinondoni districts of Dar es Salaam, no difference in patient compliance was recorded between streptomycin injection and an all-oral treatment regimen. An all-oral regimen was considered desirable because of concerns about injection-related human immunodeficiency virus (HIV) transmission, the high cost of streptomycin, and the staff time involved in providing injections; on the other hand, it was unclear whether patients would accept a change to oral ethambutol. In Kinondoni District, where an average of 127 tuberculosis patients are expected daily, 95.9% of the expected patients attended in the initial phase when streptomycin was still given, 97.1% in the transition period, and 95.7% once the oral regimen had been fully implemented. In Ilala, where there was no baseline survey due to nonavailability of streptomycin, attendance was 91.8% of expected when the oral regimen was put into place. Encouraged by these findings, Tanzania's national tuberculosis control program has replaced streptomycin injection with oral ethambutol administration. It is speculated that the shorter clinic waiting times involved in this regimen have helped to maintain a high level of attendance. In this culture, at least, oral regimens do not appear to be perceived as less effective or important than injections.