Bullous pemphigoid complicated with macroamylasemia: a case report

High amylase level is a typical sign of acute pancreatitis. However， it can also be found in other diseases. In the article， a case of persistent elevation of amylase level for over 1 year was reported. A 66-year-old male patient suffered from bullous pemphigoid complicated with diabetes mellitus for 3 years. After bullous pemphigoid treatment 8 months ago， he presented with elevated amylase level ranging from 556 to 1106 U/L， serum lipase level between 62 U/L and 73 U/L and urine amylase level between 553 U/L and 1162 U/L， respectively. The renal amylase clearance rate /creatinine clearance ratio was 0.8% （<1%）. The patient had no gastrointestinal discomforts. Abdominal color Doppler ultrasound （color ultrasound） and enhanced CT scan revealed that the pancreas was normal. Color ultrasound showed no abnormality in the thyroid and salivary gland. The possibility of salivary gland disease was excluded by stomatologist consultation. The patient was diagnosed with macroamylasemia. The patient reported no discomfort during the 8-month follow-up. The serum amylase level was gradually decreased but still higher than the normal range. This case suggested macroamylasemia should be considered when a patient present with persistent elevation of amylase level， without dynamic changes， gastrointestinal symptoms or elevated serum lipase level