Chronic pancreatitis and pancreatic pseudocyst with adult-onset type II citrullinemia.

Citrin deficiency, which is caused by a mutation of SCL25A13, can manifest in older children as failure to thrive and dyslipidemia caused by citrin deficiency (FTTDCD) and in adults as recurrent hyperammonemia with neuropsychiatric symptoms in adult-onset type II citrullinemia (CTLN2). FTTDCD and CTLN2 are known to complicate hypertriglyceridemia and chronic pancreatitis. Here we report, for the first time, the case of a patient with chronic pancreatitis and pancreatic pseudocyst with CTLN2 who was treated using endoscopic ultrasound-guided cyst drainage (EUS-CD). A 33-year-old woman with down syndrome presented to our hospital with complaints of fever, abdominal distention, and biliary vomiting for the previous 2 weeks. Owing to her difficulties in communication, although she had been taking a nutritionally balanced diet regardless of her preference, chronic pancreatitis and pancreatic stones had already been observed at the time of CTLN2 diagnosis at the age of 30 years. Three years later, a merged pancreatic pseudocyst was detected, and EUS-CD was successfully performed. A high-fat diet therapy for FTTDCD and CTLN2 may have caused the development of the pancreatic pseudocyst combined with chronic pancreatitis in this case. Pancreatic pseudocysts associated with FTTDCD or CTLN2 can be treated in a similar manner to those resulting from other causes.