Haematological Changes in Tuberculosis in Kano, Nigeria

Abstract

The potential hazard associated with the concentration processes of sputum for acid fast bacilli (AFB) and lack of culture facilities have made it inevitable for many centers which rely on direct sputum smear microscopy to under-diagnose tuberculosis. This is the situation in Kano metropolis where the prevalence rate may be difficult to determine. The aim of this study is to establish a characteristic haematological pattern which could assist in the differential diagnosis of tuberculosis. Routine haematological analysis was carried out in respect of PCV, Hb, WBC (Total and differential counts), erythrocyte sedimentation rate (ESR) and blood film examination in 290 AFB positive patients who attended the General Outpatients Departments of Infectious Diseases Hospital and Aminu Kano Teaching Hospital Kano, between April 2001 and December 2004. Age- and sex-matched healthy controls were evaluated along with the enrolled patients. The highest prevalence rate of infection 90 (31%) occurred in the age groups (21 – 30 years). In patients with pulmonary tuberculosis, the prevalence of mild anemia, raised ESR, leucocytosis, neutrophilia with toxic granulations, thrombocytosis and occasional stickiness of platelets, and monocytosis was higher (P < 0.05) than in control subjects. Of the 3 patients who were diagnosed to have disseminated tuberculosis, the only female subject showed severe anaemia with pancytopenia, while 12 patients co-infected with HIV had haematological values which were statistically lower (P<0.5) than values for healthy subjects. In conclusion, patients who present with symptoms that are suggestive of tuberculosis should be evaluated for haematological indices that can enhance the accuracy of differential diagnosis.

Keywords: Haematology, tuberculosis, Kano.

Journal of Medical Laboratory Sciences Vol. 14 (2) 2005: pp. 35-39