Radiographic findings and patterns in multidrug-resistant tuberculosis.

Multidrug-resistant tuberculosis (MDR TB) is prevalent in urban areas with large HIV-positive populations. We retrospectively evaluated the chest radiographs of MDR TB patients at presentation and compared them to patients with drug-sensitive tuberculosis (DS TB). Although the overall radiographic findings and patterns of MDR TB and DS TB were similar, there were significant differences among the MDR TB patients depending on how MDR TB was acquired. Patients who developed MDR TB during an outbreak showed noncavitary consolidations, pleural effusions, and a primary radiographic pattern (70%). On the other hand, patients who acquired MDR TB due to noncompliance with antituberculous therapy often had cavitary consolidations (50%) and generally demonstrated a postprimary radiographic pattern. Cavitation occurred equally in patients with MDR TB who are HIV positive regardless of CD4 cell count. Chest radiographic findings and patterns in MDR TB are most accurately interpreted in conjunction with clinical history, specifically prior TB treatment. Nevertheless, approximately one-third of patients did not show the "expected" radiographic pattern.