Radiological Patterns of Abdominal Tuberculosis With Microbiological Confirmation: A Multi-Modal Prospective Analysis

This study primarily aimed to evaluate the association between radiological patterns of abdominal tuberculosis (TB) and microbiological positivity using acid-fast bacillus (AFB) smear microscopy, cartridge-based nucleic acid amplification tests (CBNAATs), and polymerase chain reaction (PCR). Secondary objectives included describing the radiological manifestations of abdominal TB and comparing the microbiological diagnostic yields of these techniques.

A prospective study was conducted in patients with suspected abdominal TB who underwent cross-sectional imaging, including ultrasonography (USG), computed tomography (CT), or magnetic resonance imaging (MRI), along with microbiological testing. Radiological patterns were categorized based on the site of involvement, and imaging findings were correlated with results from PCR, CBNAAT, and AFB smear examinations.

A total of 126 patients with suspected abdominal TB were included. Bowel involvement was the most common radiological finding (112/126, 88.9%), followed by peritoneal involvement (88/126, 69.8%) and lymph node involvement (81/126, 64.3%). PCR demonstrated the highest microbiological positivity (98/126, 77.8%), followed by the CBNAAT (82/126, 65.1%) and AFB smear microscopy (44/126, 34.9%). Multi-compartment disease was significantly associated with higher microbiological positivity for PCR (42/46, 91.3% vs. 56/80, 70.0%; p=0.0109) and CBNAAT (37/46, 80.4% vs. 45/80, 56.3%; p=0.0108), whereas AFB smear positivity did not differ significantly between the groups (21/46, 45.7% vs. 23/80, 28.8%; p=0.085).

Radiological assessment demonstrates characteristic patterns of abdominal TB that are significantly associated with microbiological positivity, particularly in patients with multi-compartment involvement. However, microbiological confirmation remains essential for establishing the diagnosis. Molecular diagnostic methods such as PCR and CBNAATs showed higher microbiological yields than conventional AFB smear. An integrated approach combining radiological assessment with microbiological testing may facilitate earlier diagnosis and appropriate clinical management.