Clinical Characteristics and Genetic Causes of Infantile Exocrine Pancreatic Insufficiency in Chinese Patients: Study From a Tertiary Care Center.

OBJECTIVE: Infantile exocrine pancreatic insufficiency is a rare disease. We examined phenotypes and performed genetic sequencing in children with this disorder. METHODS: We enrolled 4 infants with exocrine pancreatic insufficiency. Patients were characterized by phenotypes and radiologic findings. Genetic sequencing was performed. RESULTS: Average age of disease onset was 2 months. Average (standard deviation [SD]) age at diagnosis was 11.9 (7.0) months. Patients presented with chronic steatorrhea and failure to thrive. Two had mild zinc deficiency. Imaging showed pancreatic lipomatosis and metaphyseal dysplasia among all patients. For these patients with similar phenotypes, genetic sequencing revealed that 2 patients had novel UBR1 mutations (c.[3043_3046delAAAG; c.3848 + 6T > C] and c.[1850-2A > T;c.4290T > G], reference sequence NM_174916), and another 2 patients had homozygous SBDS c.258 + 2T > C mutation and SBDS c.[258 + 2T > C;c.428C > T] mutations (reference sequence NM_016038.2). All patients received pancreatic enzyme replacement therapy. CONCLUSIONS: Here we described 4 patients with infantile exocrine pancreatic insufficiency confirmed by laboratory tests and imaging. Whole-exome sequencing and Sanger sequencing showed that 2 patients had Johanson-Blizzard syndrome and 2 patients had Shwachman-Diamond syndrome. Genetic sequencing should be applied for definite diagnosis among these patients.

Racial Differences in the Clinical Profile, Causes, and Outcome of Chronic Pancreatitis.

OBJECTIVES: Racial differences in susceptibility and progression of pancreatitis have been reported in epidemiologic studies using administrative or retrospective data. There has been little study, however, on the clinical profile, causes, and outcome of chronic pancreatitis (CP) in black patients. METHODS: We analyzed data on black patients with CP prospectively enrolled in the multicenter North American Pancreatitis Studies from 26 US centers during the years 2000-2014. CP was defined by definitive evidence on imaging studies or histology. Information on demographics, etiology, risk factors, disease phenotype, treatment, and perceived effectiveness was obtained from responses to detailed questionnaires completed by both patients and physicians. RESULTS: Of the 1,159 patients enrolled, 248 (21%) were black. When compared with whites, blacks were significantly more likely to be male (60.9 vs. 53%), ever (88.2 vs. 71.8%), or current smokers (64.2 vs. 45.9%), or have a physician-defined alcohol etiology (77 vs. 41.9%). There was no overall difference in the duration of CP although for alcoholic CP, blacks had a longer duration of disease (8.6 vs. 6.97 years; P=0.02). Blacks were also significantly more likely to have advanced changes on pancreatic morphology (calcifications (63.3 vs. 55.2%), atrophy (43.2 vs. 34.6%), pancreatic ductal stricture or dilatation (72.6 vs. 65.5%) or common bile duct stricture (18.6 vs. 8.2%)) and function (endocrine insufficiency 39.9 vs. 30.2%). Moreover, the prevalence of any (94.7 vs. 83%), constant (62.6 vs. 51%), and severe (78.4 vs. 65.8%) pain and disability (35.1 vs. 21.4%) were significantly higher in blacks. Observed differences were in part related to variances in etiology and duration of disease. No differences in medical or endoscopic treatments were seen between races although prior cholecystectomy (31.1 vs. 19%) was more common in white patients. CONCLUSIONS: Differences were observed between blacks and whites in the underlying cause, morphologic expression, and pain characteristics of CP, which in part are explained by the underlying risk factor(s) with alcohol and tobacco being much more frequent in black patients as well as disease duration.

Clinical Phenotypes and Genotypic Spectrum of Cystic Fibrosis in Chinese Children.

OBJECTIVES: To characterize the clinical phenotypes and genotypic spectrum of cystic fibrosis (CF) in Chinese children. STUDY DESIGN: We recruited and characterized the phenotypes of 21 Chinese children with CF. All 27 exons and their flanking sequences of the CF transmembrane conductance regulator gene were amplified and sequenced to define the genotypes. RESULTS: Bronchiectasis (95.2%) and sinusitis (76.2%) were the most common clinical presentations among our patients. By contrast, pancreatic insufficiency was rare (14.3%). The predominant organism found in the airways was Pseudomonas aeruginosa (66.7%). There were obvious reductions of forced expiratory volume in the first second (mean ± SD: 71.8% ± 17.2% predicted) and forced expiratory flows at 75% of exhaled vital capacity (33.7% ± 20.4% predicted) in children with CF. Overall, we identified 22 different mutations, including 12 missense, 5 nonsense, 2 frameshift, 1 in-frame insertion, 1 splice site, and 1 3'untranslated region mutation. Of these, 7 were novel observations (W216X[780G→A], 1092insA, Q359X, D567Y, 2623-126T→C, 3439delA and 4575+110C→G), and the most common types were L88X and I556V. One de novo mutation (1092insA) was also revealed. Except for N1303K and R334W, none of them were present in the common Caucasian CF transmembrane conductance regulator mutation-screening panels. CONCLUSIONS: There was a 5.7-year delay between the first clinical presentation and the eventual CF diagnosis, suggesting that CF may be underdiagnosed in China. The clinical phenotypes and genotypic spectrum are different from that observed in Caucasians.