Background: Clinical response means a response to drug intake that can be detected and appreciated by a change in signs and symptoms caused by the disease for which the drug, or whatever kind of therapy, is being taken. There is no single study that addresses the clinical response of tuberculosis patients in Ethiopia. The main objective of this study was to assess time to clinical response, the incidence density for clinical response and determinants of clinical response of tuberculosis patients in the intensive phase of treatment.

Methods and materials: Prospective cohort study design was implemented. The target population for this study was all tuberculosis patients following the directly observed therapy.

Initially baseline data was collected during the start of DOTS. Longitudinal data collections were collected start after 7 days of base line data collection. Then every 7 days update data was collected from each pulmonary and extra pulmonary tuberculosis patients.    Kaplan Meier curve was used to estimate time to clinical response. Incidence density using person days was used to estimate incidence of clinical response. Cox proportional hazard model was used to identify the predictors of clinical responses.

Results: A total of 1608 tuberculosis patients were included giving for the response rate of 99.5 %. The mean age of the respondents was 24.5 years [standard deviation (SD) 14.34 years]. The incidence density for clinical response was 1429/38529 person days. One forth of tuberculosis patients show clinical response at day 14, 21% of tuberculosis patients show clinical response at day 21 and 75% of tuberculosis patients show clinical response at day 31.  Predictors of clinical response for tuberculosis patients includes: age (AHR 1.007 [95% CI 1.003-1.011]), type of tuberculosis  (AOR 2.3[95 % CI 2.04 - 2.59]),  Previous history of tuberculosis ( AHR 0.18[ 95% CI 0.11-0 .30]), Intestinal parasitic infection ( AOR 0.22[95% CI 0.19-0.26]), hemoglobin ( AOR 2.35 [95% CI 2.18-2.54]), weight gain  (AOR 1.11 [95% CI 1.05-1.17]),Micronutrient supplementation (AOR 9.71 [ 95% CI 8.28-11.38]), male sex ( AOR 0.87 [95% CI 0.79-0.97]).

Conclusion and recommendation: The clinical responses for extra-pulmonary tuberculosis patients were slower than pulmonary tuberculosis. Deworming and micronutrient supplementation should be considered as additional treatment strategy for tuberculosis patients.

Key words: survival, clinical response, tuberculosis