Anal Tuberculosis: Diagnostic Challenges and Ambiguities with Crohn's Disease: A case report

Abstract Tuberculosis is an infectious disease caused by mycobacteria within the tuberculosis complex. Anal tuberculosis is a rare and often underdiagnosed form of extrapulmonary tuberculosis, accounting for approximately 1% of cases.
 We present a case of anal tuberculosis in a 40-year-old male with Crohn's disease, who developed anoperineal lesions. The patient was undergoing combination therapy, including an immunosuppressant (azathioprine) and an anti-TNF agent (infliximab). Due to the persistence of symptoms, a GeneXpert test was performed on an anal fistula to detect acid-fast bacilli, yielding a positive result.
 Infection in the anorectal region can occur through ingestion of sputum containing the bacilli, direct inoculation via anal skin fissures, or, more rarely, hematogenous dissemination.
 Ziehl-Neelsen staining for acid-fast bacilli is not always definitive. Histological examination plays a key role in identifying epithelioid giant-cell granulomas and caseous necrosis. Culturing the bacteria on specialized media can take 2 to 3 months, a delay that is incompatible with the urgent need for treatment. Therefore, the GeneXpert MTB/RIF assay is preferred for its high sensitivity, specificity, speed, and ease of use.
The diagnosis of tuberculosis is often complex and relies on a combination of clinical, radiological, histological, and biological evidence, as well as a positive response to antituberculous therapy. Email addresses aminaachraibi@gmail.com, sofiafellah96@gmail.com, keddaif@gmail.com, doae.arjoudane@gmail.com, Mr_bennani@outlook.com, najoua1497.bn@gmail.com, hamza.goura@um5s.net.ma, benlahlouyassine@gmail.com benaissaelmostafa2@gmail.com, mariamachadli@gmail.com