Coefficient of Fat Absorption to Measure the Efficacy of Pancreatic Enzyme Replacement Therapy in People With Cystic Fibrosis

Abstract

Objectives: We sought data on the validity, reliability, responsiveness, and feasibility of the coefficient of fat absorption (CFA) as a measure of pancreatic enzyme replacement therapy (PERT) efficacy in people with cystic fibrosis (pwCF) and reviewed the literature for alternative measures. Methods:We searched PubMed for the Medical Subject Heading cystic fibrosis and the key words cystic fibrosis, fat absorption, CFA, and fecal fat imbalance; historical articles; and citations in bibliographies. Results:The lower the CFA, the greater its variability; thus, it is less variable in healthy individuals who have higher CFA than pwCF. In addition, the test-retest values for CFA are more variable in pwCF than the general population. There is no correlation between CFA and body mass index or PERT dose but CFA is related to gastrointestinal signs and symptoms. Research-quality CFA studies are expensive, time consuming, and odious to pwCF and research staff. Sparse stool tests, breath tests, and blood tests of fat absorption have been studied as potential alternatives to CFA to measure PERT efficacy.Conclusions: Based on the evidence, we conclude that CFA as a measure of the efficacy of PERT is more of a "coal standard" than a gold standard; developing suitable alternatives should be a priority.

Fat malabsorption in pancreatic cancer: Pathophysiology and management

“…These regimens have high risks of gastrointestinal toxicities, including nausea, vomiting, and diarrhea, which often T A B L E 1 Available assessments to diagnose EPI, including the rationale and limitations for use. 8 result in impaired oral intake in the absence of aggressive symptom control and targeted nutrition therapies. 23 It is critical to maintain nutrition intake during neoadjuvant therapy because the ultimate goal is to successfully undergo surgical resection, and malnutrition may present a barrier to surgery.…”

“…20,52,53 Alternatively, PERT may be dosed according to g of dietary fat intake (500-4000 UL per gram of dietary fat) or body weight (500-2500 UL per kilogram of body weight per meal). 8,54 However, it should be noted that these adjusted dosing strategies have primarily been studied and employed in children with cystic fibrosis. Nevertheless, the concept of using an individualized approach is reasonable because dietary patterns vary widely between individuals and may change over time (eg, during chemotherapy treatments).…”

“…Most guidelines advise starting PERT at a dose of at least 50,000 units of lipase (UL) per meal and 25,000 UL with snacks, which may be further adjusted based on symptoms, laboratory parameters, and anthropometric measures 20,52,53 . Alternatively, PERT may be dosed according to g of dietary fat intake (500–4000 UL per gram of dietary fat) or body weight (500–2500 UL per kilogram of body weight per meal) 8,54 . However, it should be noted that these adjusted dosing strategies have primarily been studied and employed in children with cystic fibrosis.…”

Fat malabsorption in short bowel syndrome: A review of pathophysiology and management

“…Diagnostic tests for fat malabsorption are primarily based on those in the cystic fibrosis (CF) and chronic pancreatitis literature for evaluation of pancreatic enzyme insufficiency. 55 As fat malabsorption, by definition, results in increased fecal fat content, measurement of fecal fat is often the initial step. The Sudan stain is an inexpensive, easy, and reasonably sensitive qualitative test of fat malabsorption (Table 4).…”

“…Fat malabsorption may be suspected clinically in the SBS patient with steatorrhea, weight loss, failure to thrive, fat‐soluble vitamin deficiencies, or EFAD. Diagnostic tests for fat malabsorption are primarily based on those in the cystic fibrosis (CF) and chronic pancreatitis literature for evaluation of pancreatic enzyme insufficiency 55 . As fat malabsorption, by definition, results in increased fecal fat content, measurement of fecal fat is often the initial step.…”