Extra-pulmonary tuberculosis in Uyo, South - South, Nigeria

Abstract

Background: Tuberculosis is a disease of the poor, affecting the pulmonary and extra-pulmonary organs.

Objectives: To assess the frequency and morphologic pattern of extra-pulmonary tuberculosis as well as determining the occurrence of other acid fast organisms from extra-pulmonary tissue biopsies using common routine and special stains.

Methods: A review of all the clinical and pathological records and slides of histopathologically diagnosed extra -pulmonary tuberculosis was undertaken.

Results: Extra-pulmonary tissue samples with tuberculosis (n=52) constituting 1.46% of a total number of samples received during the years under review. Male to female ratio was 1.1:1. Modal age group was 21-30 years. Mean age was 28.3 years. Thirty seven (71.1 %) cases occurred in patients aged under 30 years while the remaining 15 (28.9%) cases occurred in the patients aged above 30 years. Lymph node was the most preponderant extra-pulmonary tuberculosis site, constituting 30 (57.7%) cases with the axillary lymph node being the most common site in 18 (60.0%) cases. Neither tubercle bacilli nor other acid fast bacilli including Nocardia, and Cryptosporidium was demonstrated in the extra-pulmonary tissue biopsies.

Conclusion: Conventional ZN has limitations in diagnosis of extra-pulmonary tuberculosis. More sensitive and specific methods including fluorescent methods, polymerase chain reaction (PCR) and immunohistochemistry are suggested before reporting the negative results.

Keywords: Acid fast bacilli, extra-pulmonary tuberculosis, biopsy specimens