In a case of bilateral recurrent haemorrhagic pleural effusion due to asymptomatic pancreatitis the diagnosis was suggested by the presence of amylase in the pleural fluid when other possible causes had been excluded. Abdominal computed tomography and laparotomy confirmed the diagnosis. No communications could be seen between the peritoneal and pleural space at laparotomy.Pleural effusion is an uncommon complication of pancreatitis. It is often left sided and associated with acute pancreatitis."2 Development of massive and recurrent haemorrhagic pleural effusion on one side followed by effusion on the opposite side after a relatively symptom free interval in a patient with no clinical evidence of pancreatic disease must be very rare.3Case report A 38 year old man, a hospital store keeper in the army, presented with cough and dyspnoea of seven days' duration on accustomed exertion. The findings from clinical and radiological examination were consistent with a massive left sided pleural effusion (figure). The patient denied any past illness except for a vague abdominal pain nine months earlier, which had lasted for 12 hours. Pleural fluid was port wine colour and contained 72 g/l protein, 3-3 mmol/l glucose, (blood glucose 5-4 mmol/l), cells 0-4 x 109/l (mostly lymphocytes), red blood cells 10-8 x 109/1. No malignant cells or acid fast organisms were seen on smears and cultures were sterile. Bronchoscopy and bronchoalveolar lavage studies were noncontributory. Pleural biopsy showed normal pleura.Malignant causes having been reasonably excluded and because tuberculosis is an extremely common cause of pleural effusion in India, the patient was treated with a short term chemotherapeutic regimen of isoniazid, rifampicin, pyrazinamide, and streptomycin for two months followed by isoniazid and rifampicin daily for seven months. Prednisolone 1 mg/kg was given initially with reduction of the dose within four weeks. Accepted 15 June 1989 The pleural effusion continued to accumulate and 4 5 litres of fluid were aspirated on four occasions over the next three weeks. Thoracic computed tomography showed no pulmonary, pleural, or mediastinal lesion except for the pleural effusion. As the patient was becoming dyspnoeic a left thoracotomy was done; this showed slight thickening of the parietal pleura over the upper lobe. A pleura biopsy specimen showed no specific abnormality. An abrasive pleurodesis was carried out and he remained symptom free for the next 12 weeks.A similar massive haemorrhagic pleural effusion was then found on the right side (figure). Three litres of fluid were removed in four sessions. As all common causes had been reasonably excluded the amylase activity of the pleural fluid was measured and found to be very high at 48 900 Somogyi units/l. Blood amylase activity was normal (120 Somogyi U/1). Computed tomography of the abdomen showed an enlarged head of the pancreas containing cystic lesions; no calcification was seen. Abdominal ultrasound did not show gallstones. As the pleural fluid continued t...