Pulmonary Tuberculosis in HIV Infection : The Relationship of the Radiographic Appearance to CD4 T-Lymphocytes Count

Abstract

Pulmonary tuberculosis (TB) in the AIDS population has a variable chest radiographic presentation. The association between the chest radiographic presentation of pulmonary TB and CD4 T-lymphocyte count in the HIV-infected patient was investigated in order to provide an empirical approach for early diagnosis, treatment, and isolation of these patients. A retrospective analysis of chest radiographs, CD4 T-lymphocyte counts, and clinical history of 80 patients from Hospital Kota Bharu, was performed. All patients were HIV-seropositive and had culture and /or cytology-proven pulmonary tuberculosis. Radiographs were evaluated for the presence of atypical or typical patterns of pulmonary TB. Thirteen (16.2%) patients had typical postprimary pattern, where opacities were distributed at the upper zones, with or without cavitation. Sixty-seven (83.8%) patients had atypical patterns, consisting of normal chest radiograph, middle and/or lower zones parenchymal opacities, mediastinal lymphadenopathy, pleural effusion and miliary TB. Of these, 18 (22.5%) patients demonstrated normal chest radiographs, 36 (45%) patients showed parenchymal opacities at the middle and/or lower zones of the lungs, 30 (37.5%) had mediastinal lymphadenopathy, 18 (22.5%) revealed pleural effusion and 6 (7.5%) presented with miliary TB. Sixty-two (77.5%) patients had CD4 T-lymphocytes count less than 200 cells/ul. Of these patients, only 1 (1.6%) had typical pattern. Eighteen (22.5%) patients had CD4 T-lymphocyte count more than 200 cells/ul, where 12 (66.7%) of them showed typical pattern. Patients with CD4 T-lymphocytes count of less than 200 cells/ul, were more likely to produce normal chest radiographs, middle and /or lower zones parenchymal opacities and mediastinal lymphadenopathy. The mean CD4 T-lymphocytes count were also found significantly lower. AIDS patients with pulmonary TB can present with both typical and atypical chest radiograph patterns. An AIDS patient who had CD4 T-lymphocytes count less than 200 cells/ul were more likely to present with atypical radiographic appearance of pulmonary TB. They required appropriate treatment and isolation until the diagnosis of pulmonary TB was confirmed.

Keywords: AIDS; Atypical patterns; CD4 T-lymphocytes count; Chest radiograph; HIV infection; Pulmonary tuberculosis.