Case Presentation: 54-year-old female with history of anemia and fibroids presented with progressive dyspnea, generalized weakness, weight loss, and worsening abdominal pain and distention. Four months prior, patient presented similarly and was diagnosed with peritoneal carcinomatosis with an unclear primary. A positive Quantiferon TB was also noted on that admission. She emigrated from Jamaica in 2012, received BCG vaccine at the age of five, had no known TB exposure but did work as a school nurse previously.Labs were notable for Hemoglobin 9.3, protein-albumin gap of 6.1, and corrected calcium of 13.0. ANA, ANCA, HIV, HPV, hepatitis, serum and urine immunofixations were all negative. Pulmonary TB was ruled out with three negative sputum AFB samples. CT Chest, abdomen and pelvis revealed increased retroperitoneal adenopathy, peritoneal metastatic disease with omental caking, and small abdominopelvic ascites. IR guided biopsy of a retroperitoneal lymph node showed lymphoid tissue with granulomas with non-diagnostic flow cytometry for both samples. Omental mass biopsy revealed non-necrotizing and rare necrotizing granulomata. AFB and GMS stains were negative for microorganisms. Sheets of highly atypical cells with enlarged nuclei, pale, delicate cytoplasm in the background of abundant sheets of reactive mesothelial cells and chronic inflammation were seen on cytology smears. Diagnostic paracentesis was exudative with PMNs>250 cells/mm3, therefore, completed five days of IV ceftriaxone for presumed SBP although peritoneal culture was negative. Ascitic fluid analysis preliminary was negative for AFB and malignant cells but noted lymphocytic predominance with serum-ascites albumin gradient <1.1. Post hospital discharge, ascitic fluid came back positive for mycobacterium tuberculosis after nearly three weeks of incubation. Patient was started on RIPE therapy for 2 months, followed by 4 months with rifampin and INH with vitamin B6 to complete treatment.
Discussion: The diagnosis of peritoneal tuberculosis is often delayed and even misdiagnosed due to its insidious nature, nonspecific biological markers, long incubation times for cultures and the absence of characteristic radiographic signs. The gold standard for diagnosis is growth of mycobacterium tuberculosis from ascitic fluid or peritoneal biopsy. Diagnostic delays and delayed initiation of treatment can lead to high morbidity and mortality rates. In this case, nearly five months elapsed since the first positive Quantiferon test to the confirmed diagnosis of peritoneal TB but luckily, the patient made a full recovery.
Conclusions: The diagnosis of extrapulmonary forms of TB especially for the peritoneal type requires a high clinical suspicion. Patients presenting with abdominal pain, weight loss, fever, and lymphocytic dominant ascites with serum-ascites albumin gradient < 1.1 g/L, peritoneal TB should be considered in the differential diagnosis.