Presentations

Abstract

Introduction:

Chronic pancreatitis (CP) can result from episodes of an acute pancreatitis of any cause. The syndrome of chronic pancreatitis results from exposure to risk factors (genetic and environmental). Cystic Fibrosis (CF) is one of the genetic disorders caused by CF transmembrane conductance regulator gene (CFTR) mutation which can lead to chronic pancreatitis in 15-20 percent of cases.

Case description:

A 20 year old male with a past medical history of asthma, gastroparesis and eosinophilic esophagitis was admitted with recurrent episodes of acute pancreatitis. He denied using tobacco, alcohol or illicit drugs. His first episode 6 months ago was of unclear etiology. MRI MRCP showed evidence of acute pancreatitis without evidence of necrosis, abscess ,cholelithiasis or presence of annular pancreas or pancreas divisum. Anti nuclear antibodies and IGG4 subtypes were negative. Since this episode, the patient has had multiple attacks of symptomatic pancreatitis, some of which were complicated by pancreatic necrosis.

Related to diagnostic uncertainty a 6 gene panel for chronic pancreatitis was sent to Invitae Genetics which revealed heterozygous pathogenic mutations (p.Phe508del and p.Met952IIe). CT of the chest and sinuses showed no pathology and a sweat chloride was negative (20mmol/L). The patient was subsequently referred to a cystic fibrosis clinic where it is anticipated Trikafta (elexacaftor/tezacaftor/ivacaftor) will be prescribed.

Discussion:

The classic or typical form of CF is diagnosed if a patient demonstrates clinical disease in one or more organ systems and has elevated sweat chloride (≥60 mmol/L). Patients with CFTR mutations and chronic pancreatitis who do not fit the diagnostic criteria for CF often can be categorized as having either "nonclassic CF" or "CFTR-related disease. These patients are more likely to present later in childhood or adulthood and to have unusual CFTR mutations, which may not be included in the standard CF screening panel. They may still be diagnosed with CF if they meet the genetic criteria for the diagnosis, including two copies of a disease-causing mutation in the CFTR gene on each parental allele. Our patient falls under this category by having only one organ system involved (gastrointestinal) and having a negative sweat chloride test. However he did have 2 mutations in CFTR gene which is consistent with atypical CF diagnosis.

Conclusion:

On rare occasions pancreatitis may be the initial presenting symptom of CF even in the absence of any other organs involved particularly lungs. It is reasonable to perform a genetic testing for CFTR gene mutation in this patient population to initiate an early treatment and to prevent the devastating sequelae of chronic pancreatitis.