Relationship of the Manifestations of Tuberculosis to CD4 Cell Counts in Patients with HIV Infection

Objectives: To study the various clinical and radiological manifestations of tuberculosis, AFB status, tuberculin reactivity in HIV positive patients and its relationship with the CD4 cell counts. Methods: Symptomatic patients with confirmed serodiagnosis of HIV infection were screened for pulmonary tuberculosis (PTB) as well as for extra-pulmonary tuberculosis (EPTB), diagnosis of tuberculosis was made using different modalities.Tuberculin testing and CD4 cell counts were also determined. Results: Seven hundred and seventy two patients with HIV infection were included in the study. Eighty seven patients (11.3%) were diagnosed with concurrent active tuberculosis. Pulmonary tuberculosis only was seen in 28 of the 87 (32.2%) patients. Forty two patients (48.3%) had only extra-pulmonary tuberculosis, whereas 17 (19.5%) had both pulmonary as well as extra pulmonary tuberculosis. Commonest form of EPTB in our study was tubercular lymphadenopathy, detected in 19 (21.8%) patients. On tuberculin testing, out of total 87 patients, 33 (37.9%) had induration ≥ 5 mm (sensitivity 37.93%) while 23 (26.4%) developed induration ≥10 mm (sensitivity 26.43%). Chest X-ray of 42 (48.3%) of HIV-TB patients showed tubercular findings. In patients with CD4 count < 200 cells/μl, fourteen patients (66.7%) had atypical findings while 7 (33.4%) patients had typical radiographic picture. AFB smear-negativity and culture-positivity in PTB was more common with decrease in CD4cell count. Conclusions: The lack of rapid and accurate TB diagnostic tools and the lack of a standardized symptom and sign-based screening strategy has posed a challenge to the accurate and prompt diagnosis of tuberculosis in HIV infected patients. Available information, experience, and data have to be used to develop a simple and standardized TB screening strategy for use in settings with a high prevalence of HIV infection.