Comparison of demographic and clinical characteristics between pulmonary and extra-pulmonary tuberculosis patients in Kiambu County, 2012-2015

Abstract

Background: Tuberculosis (TB) continues to be a public health challenge globally. The most common organ to be involved is the lung although it can affect any organ in the body. The diagnosis of extra-pulmonary TB (EPTB) has faced many challenges mainly due to inadequate expertise to diagnose or lack of equipment for diagnosis.

Objective: To compare the demographic and clinical characteristics between pulmonary and extrapulmonary tuberculosis in Kiambu County

Design: Retrospective cross-sectional study

Setting: Kiambu County, Kenya

Subjects: Tuberculosis patients notified in TIBU surveillance system

Results: Of the 15, 833 patients analyzed, 2,704 (17%) had extra-pulmonary tuberculosis. Male to female ratio was 1:1.7 in PTB and 1:1.3 in EPTB patients. There was declining trend of TB cases notified over the years for both PTB and EPTB. Pleural TB accounted for 38% with TB lymphadenitis accounting for 14% of the EPTB subtypes. TB-HIV co-infection was higher among EPTB (36%) compared to PTB (30%). The treatment success rate was 85% and 86% among PTB and EPTB cases respectively. The mortality was 10% among EPTB and 5% in PTB cases. The 5-14 age category were more likely to developing EPTB compared to PTB (AOR 4.67 95% CI (1.5-13.99). Kabete zone was most affected with EPTB (AOR 2.11(1.19-2.74) while a protective factor was observed among the HIV positive clients (AOR 0.58 (0.43 - 0.78)

Conclusion: There was a general decline in cases for both EPTB and PTB. However, the age category most affected was 5-14 years. The co-infectivity rate was higher among the EPTB patients compared to the PTB patients. High index of suspicion and appropriate diagnostic tools are needed in evaluation particularly in EPTB which will assist in early management of the patients. ART uptake could play a big role in protecting HIV positive clients from getting EPTB.