Tuberculous Peritonitis

Tuberculous peritonitis is infection of the peritoneum by Mycobacterium tuberculosis from reactivation of latent foci, lymph node rupture, intestinal disease or the fallopian tubes, and is common in HIV and cirrhosis. Forms: wet (ascitic), dry (adhesive) and fibrotic.

• Risk factors: HIV, cirrhosis, diabetes, renal failure on peritoneal dialysis, immunosuppression, alcohol, malnutrition.
• Women in the third and fourth decades are commonly affected.

Abdominal distension, pain, ascites, fever, weight loss, night sweats, anorexia; doughy abdomen and palpable omental masses.

• Features of intestinal obstruction in fibrotic disease; menstrual disturbance or infertility when pelvic organs are involved.
• Differential diagnosis: cirrhotic ascites, peritoneal carcinomatosis, ovarian cancer, lymphoma, Crohn disease, heart failure, nephrotic syndrome, pancreatic ascites, spontaneous bacterial peritonitis, fungal peritonitis, hepatic schistosomiasis, abdominal lymphoma.
• Complications: intestinal obstruction, fistula, abdominal abscess, perforation, malnutrition, hepatic decompensation, relapse.

Combine ascitic fluid analysis with imaging and tissue.

• Ascitic fluid: exudate (protein over 25 g/L, serum ascites albumin gradient under 11 g/L in non cirrhotic patients), lymphocyte predominance (over 70 percent), adenosine deaminase over 39 U/L; Xpert MTB/RIF Ultra and culture of large volumes (low yield); cytology to exclude malignancy.
• Ultrasound and CT abdomen (omental thickening, mesenteric nodes, peritoneal enhancement, loculated ascites); chest radiograph and sputum Xpert.
• Laparoscopy with peritoneal biopsy (miliary nodules, adhesions, caseating granuloma) gives definitive diagnosis; CA 125 may be raised but does not separate tuberculosis from cancer.
• HIV test, CD4, liver function.

Six months of antituberculous therapy; avoid unnecessary surgery.

• Supportive: nutrition (high protein, energy), paracentesis for tense ascites, correction of electrolytes, analgesia, nutritional supplements, management of cirrhosis if present.
• Pharmacological: 2 months of isoniazid, rifampicin, pyrazinamide and ethambutol followed by 4 months of isoniazid and rifampicin (daily doses isoniazid 5 mg/kg, rifampicin 10 mg/kg, pyrazinamide 25 mg/kg, ethambutol 15 mg/kg), with pyridoxine 25 to 50 mg daily; extend in cirrhosis or slow response. Steroids are not routine. Antiretroviral therapy within 2 weeks if CD4 under 50, otherwise by 8 weeks; dolutegravir 50 mg twice daily with rifampicin. Diuretics (spironolactone 100 mg daily with furosemide 40 mg daily) only in cirrhosis or portal hypertension.
• Procedures: diagnostic or therapeutic paracentesis; laparoscopic or ultrasound guided biopsy; laparotomy only for obstruction not resolving, perforation or abscess.
• Special groups: cirrhosis, hepatotoxicity risk, use a regimen with fewer hepatotoxic drugs and monitor liver tests weekly at the start; pregnancy, first line regimen with pyridoxine; peritoneal dialysis patients, specialist management; HIV, watch for paradoxical reactions.
• Red flags: acute abdomen, obstruction, perforation, fever with hypotension, rising ascites despite treatment, jaundice on therapy, suspicion of malignancy.
• Follow-up: clinical and weight review monthly; ultrasound at 2 and 6 months; liver tests at 2 and 4 weeks and as needed.