Background: Sarcoidosis is a diffuse granulomatosis predominately with mediastino-pulmonary localization. A wide range of extrathoracic localizations can also be seen like the central nervous system, eyes and skin.
Case Report: A 62-year-old female patient was admitted to hospital with diffuse abdominal pain. As it followed from her medical history, she had received a laparotomy for abdominal pain of unknown etiology four years before. Histopathological examination of extracted lymph nodes had shown a granulamatous reaction, and the patient had been given anti-tuberculosis therapy. The patient had received no benefit from this therapy and continued
to have epigastric pain and lose weight. We evaluated the patient by endoscopy, colonoscopy, and imaging studies, in addition to ultrasound, Doppler ultrasound, computed tomography, and magnetic resonance
imaging. These studies showed a retroperitoneal mass. The evaluation of endoscopic biopsy samples revealed the presence of granulomas in the gastric mucosa. The patient had another laparotomy, and peritoneal and
lymph node sampling was performed. The histopathological examination of these materials revealed granulomatous reaction with Schauman and Astroid bodies and without caseification necrosis, suggesting the diagnosis
of peritoneal sarcoidosis. Pulmonary examination by computed tomography showed grade 1 pulmonary sarcoidosis, however, no other organ involvement could be detected. The patient was put on prednisone (40
mg/daily) and azathioprine (100 mg/daily). This therapy was gradually changed to prednisone 10 mg/daily alone in the third month, after peritoneal involvement and abdominal lymph nodes were resolved and the patient
was asymptomatic. The patient has been on follow-up for 12 months and is still asymptomatic.
Conclusion: Patients with non-specific abdominal pain and no diagnosis should be evaluated for peritoneal sarcoidosis. Sarcoidosis should be kept in mind in the differential diagnosis of peritoneal nodules, exudative ascites
and abdominal lymphadenopathies. If the diagnosis is once established by histology, the disease must be treated by oral steroids.

Keywords: sarcoidosis, peritoneal, lymph node, Ascites