Unusual patterns of tuberculosis on cross-sectional imaging: a pictorial review

Abstract

Background: Tuberculosis is routinely encountered on imaging throughout the world. Radiologists are usually familiar with the common patterns of tuberculosis on cross-sectional imaging. However, tuberculosis frequently presents with unfamiliar imaging patterns and/or uncommon anatomic sites which still pose a diagnostic challenge. Discussion: Rapid improvements in the management of acquired immunodeficiency syndrome patients leading to increased survival as well as advances in chemotherapy and immunosuppressive medication have complicated the presentation of tuberculosis by increasing the probability of unconventional sites and patterns of involvement in tuberculosis leading to unfamiliar imaging appearances. In this review, we describe these unfamiliar imaging patterns of tuberculosis and provide a diagnostic protocol for arriving at the right diagnosis and differentiating these from other pathologies with similar imaging appearances. These are described through case-based illustrations of unusual patterns and anatomic locations of tuberculosis. Conclusions: It is important for radiologists to be aware of such unusual imaging patterns of tuberculosis in order to facilitate early and accurate diagnosis for appropriate patient management in the face of changing patient demographics and pathological profile of tuberculosis in the current era of scientific advancements.