This 16-year-old boy, from a village in Fars Province, Southern Iran, developed left paraumblical (sometimes epigastric)abdominal pain with moderate intensity about five months prior to admission. The pain subsided after three months. However, 20 days later, the patient developed right-sided shoulder and chest pain accompanied with dyspnea. The patient's severe shoulder pain was mismanaged by a physician who considered it musculoskeletal pain. The patient then referred to Nemazee Hospital, the main hospital of southern Iran. His chest X-ray showed massive right-sided pleural effusion and thoracentesis revealed a dark red bloody effusion with: amylase: 8840 U/L (serum amylase: 3318 U/L), protein: 2.5 mg/dL (serum albumin: 4.1 mg/dL), lactate dehydrogenase (LDH): 227 U/L (serum LDH: 335 U/L), cell count: 590000 cells/mm3 with 2500 WBC/mm3 which has 73% segment, 2% lymphocyte and 6% mesothelial cell. Acid fast staining ofpleural fluid was negative three times. The results of pleural biopsy and pleural fluid culture for Tuberculosis were negative as well.
Important peripheral blood laboratory values were as follows: hemoglobin: 9.2 g/dL; white blood cell count: 7700/mm3; platelet count: 421000/mm3; mean corpuscular volume: 63.3 fl; mean corpuscular hemoglobin: 18.7  g; fasting blood sugar: 96 mg/dL; lactate dehydrogenase:335 U/L (nl: 120-230 U/L); serum glutamic-oxaloacetic transferase (SGOT):40 U/L; serum glutamic-pyruvic transaminase (SGPT): 15 U/L; alkaline phosphatase: 119 U/L; total bilirubin: 0.4 mg/dL; direct bilirubin: 0.2 mg/dL; prothrombin time: 13_ (control: 13_); partial thromboplastin time: 50_ (control: 35-45_); total calcium: 9.2 mg/dL; albumin: 4.1 mg/dL; triglyceride: 89 mg/dL (nl: 60-160 mg/dL); erythrocyte sedimentation rate (Westergen): 18 mm/hr; serum C-reactive protein: 12 mg/L (nl: <8 mg/L); serum fibrinogen: 215 mg/dL (nl: 200-400 mg/dL); fibrin split products: 9  g/mL (nl: <10  g/mL). Pleural fluid cytology (three times) and bronchial washing cytology were also negative. Due to markedly elevated serum and pleural fluid amylase abdominal CT scan was done 2 days after insertion of chest tube at the 8th day of hospitalization. The imaging showed a cystic structure measuring about 5 x 2 cm in the head of pancreas, highly suggestive of a pancreatic pseudocyst (Fig. 1). Also, abdominal ultrasonography revealed a small septated cystic structure in the head of the pancreas which was edematous and suggestive of pseudocyst of acute pancreatitis. Hepatobiliary tract and gall bladder were devoid of any gall bladder lesions, including stones. The patient had no history of drug and alcohol intake or abdominal trauma. His sweat chloride concentration was 21 meq/L.
Chest tube was inserted for three weeks, during this period the clinical symptoms such as dyspnea and chest pain improved but not completely. Thedaily drain output was about 1500 cc at the first day of chest tube insertion but it decreased gradually. After this period of conservative therapy another abdominal CT scan showed a mass measuring 3 4 cm in the head of pancreas with possibility of pseudocyst. No evidence of pancreatic duct dilatation or common bile duct dilatation was seen. Therefore external psendocyst drainage was done with mushroom insertion. Mushroom was removed after one week when no drainage was seen. Finally the patient was discharged after 40 days of hospitalization. The cause of pancreatitis could not be identified.