Tuberculous versus malignant peritoneal effusion: a diagnostic dilemma when both conditions coexist

Differential diagnosis between tuberculous peritonitis and peritonitis carcinomatosis is often extremely difficult as they share common clinical and radiologic findings like ascitis, adnexal masses and elevated CA 125 levels in women. The diagnostic dilemma is further confounded when the two conditions co-exist. Overwhelming clinical features of tuberculosis may at times mask the co-existent malignant pathology leading to its underdiagnosis by the clinicians, thereby impacting the further management of the patient. We present a case of an elderly woman who presented with abdominal distension and weight loss. Her CA 125 level was raised to 529 U/ml. Imaging studies revealed adnexal masses and ascitis. Ovarian malignancy was highly suspected but histology of endometrial biopsy showed tuberculosis. Anti-tubercular treatment was administered and the patient showed mild initial improvement but worsening of clinical and biochemical parameters occurred later due to co-existent malignancy for which no treatment was given. This case highlights the importance of a co-ordinated team work between the physician, radiologist and the pathologist. It also emphasizes the need for careful, correct and detailed analysis and interpretation of the biochemical and pathological test results to reach to a correct diagnosis.