A new variant in the ZCCHC8 gene: diverse clinical phenotypes and expression in the lung.

Introduction: Pulmonary fibrosis is a severe disease which can be familial. A genetic cause can only be found in ∼40% of families. Searching for shared novel genetic variants may aid the discovery of new genetic causes of disease. Methods: Whole-exome sequencing was performed in 152 unrelated patients with a suspected genetic cause of pulmonary fibrosis from the St Antonius interstitial lung disease biobank. Variants of interest were selected by filtering for novel, potentially deleterious variants that were present in at least three unrelated pulmonary fibrosis patients. Results: The novel c.586G>A p.(E196K) variant in the ZCCHC8 gene was observed in three unrelated patients: two familial patients and one sporadic patient, who was later genealogically linked to one of the families. The variant was identified in nine additional relatives with pulmonary fibrosis and other telomere-related phenotypes, such as pulmonary arterial venous malformations, emphysema, myelodysplastic syndrome, acute myeloid leukaemia and dyskeratosis congenita. One family showed incomplete segregation, with absence of the variant in one pulmonary fibrosis patient who carried a PARN variant. The majority of ZCCHC8 variant carriers showed short telomeres in blood. ZCCHC8 protein was located in different lung cell types, including alveolar type 2 (AT2) pneumocytes, the culprit cells in pulmonary fibrosis. AT2 cells showed telomere shortening and increased DNA damage, which was comparable to patients with sporadic pulmonary fibrosis and those with pulmonary fibrosis carrying a telomere-related gene variant, respectively. Discussion: The ZCCHC8 c.586G>A variant confirms the involvement of ZCCHC8 in pulmonary fibrosis and short-telomere syndromes and underlines the importance of including the ZCCHC8 gene in diagnostic gene panels for these diseases.

Disease phenotype at diagnosis in pediatric Crohn's disease: 5-year analyses of the EUROKIDS Registry.

BACKGROUND: It has been speculated that pediatric Crohn's disease (CD) is a distinct disease entity, with probably different disease subtypes. We therefore aimed to accurately phenotype newly diagnosed pediatric CD by using the pediatric modification of the Montreal classification, the Paris classification. METHODS: Information was collected from the EUROKIDS registry, a prospective, web-based registry of new-onset pediatric IBD patients in 17 European countries and Israel. When a complete diagnostic workup was performed (ileocolonoscopy, upper gastrointestinal [GI] endoscopy, small bowel imaging), CD patients were evaluated for ileocolonic disease extent, esophagogastroduodenal involvement, and jejunal/proximal ileal involvement. Disease behavior and the occurrence of granulomas were also analyzed. RESULTS: In all, 582 pediatric CD patients could be classified according to the Paris classification. Isolated terminal ileal disease (± limited cecal disease) was seen at presentation in 16%, isolated colonic disease in 27%, ileocolonic disease in 53%, and isolated upper GI disease in 4% of patients. In total, 30% had esophagogastroduodenal involvement and 24% jejunal/proximal ileal disease. Patients with L2 disease were less likely to have esophagogastroduodenal involvement or stricturing disease than patients with L1 or L3 disease. Terminal ileal disease and stricturing disease behavior were more common in children diagnosed after 10 years of age than in younger patients. Granulomas were identified in 43% of patients. CONCLUSIONS: Accurate phenotyping is essential in pediatric CD, as this affects the management of individual patients. Disease phenotypes differ according to age at disease onset. The Paris classification is a useful tool to capture the variety of phenotypic characteristics of pediatric CD.

Atypical disease phenotypes in pediatric ulcerative colitis: 5-year analyses of the EUROKIDS Registry.

BACKGROUND: Definitive diagnosis of pediatric ulcerative colitis (UC) may be particularly challenging since isolated colitis with overlapping features is common in pediatric Crohn's disease (CD), while atypical phenotypes of UC are not uncommon. The Paris classification allows more accurate phenotyping of atypical inflammatory bowel disease (IBD) patients. Our aim was to identify the prevalence of atypical disease patterns in new-onset pediatric UC using the Paris classification. METHODS: Information was collected from the EUROKIDS Registry, an inception cohort of untreated pediatric IBD patients undergoing evaluation at diagnosis. Patients with IBD-unclassified were excluded. Patients with isolated Crohn's colitis served as a control group. RESULTS: Data from 898 pediatric patients (643 UC, 255 CD colitis) were included. Extensive or pancolitis was present in 77% of UC patients and macroscopic rectal sparing in 5%. Rectal sparing was inversely associated with age (mean age with rectal sparing 9.9 years vs. 11.8 without; P = 0.02). Upper gastrointestinal (UGI) involvement occurred in 4% of patients. Erosions in the stomach were present in 3.1% of children, but frank ulcerations in 0.4%; 0.8% of children had erosions or ulcerations limited to the esophagus or duodenum. The corresponding UGI involvement in Crohn's colitis was 22%. A cecal patch occurred in 2% of patients. CONCLUSIONS: Extensive disease and rectal sparing are age-dependent phenotypes in pediatric UC. Rectal sparing, cecal patch, backwash ileitis, and gastric erosions are not uncommon at diagnosis, while gastric ulcerations and erosions in the duodenum or esophagus are. Recognition of atypical phenotypes in pediatric-onset UC is crucial to prevent misclassification of IBD.

Diagnostic workup of paediatric patients with inflammatory bowel disease in Europe: results of a 5-year audit of the EUROKIDS registry.

OBJECTIVE: In 2005, the Inflammatory Bowel Disease (IBD) Working Group of the European Society for Pediatric Gastroenterology, Hepatology, and Nutrition published consensus guidelines on the diagnostic workup of paediatric IBD, the Porto criteria. According to these guidelines, children suspected of having IBD should undergo an oesophagogastroduodenoscopy (OGD), ileocolonoscopy, and (except in cases of definitive ulcerative colitis) adequate imaging of the small bowel. To audit and evaluate the diagnostic workup of paediatric patients with IBD in Europe, the Working Group created EUROKIDS, a prospective, Web-based registry of newly diagnosed paediatric patients with IBD. METHODS: Patients with IBD (ages 0-18 years) were registered in 44 centres in 18 countries. Data on diagnostic workup were analysed according to the year of diagnosis, type of IBD, and centre size. Diagnostic yield of OGD and ileal intubation were evaluated. RESULTS: Between 2004 and 2009, 2087 newly diagnosed patients were correctly registered. Both OGD and ileocolonoscopy had been performed in 64% of all of the patients and increased significantly from year 1 (52 %) to 5 (71%, P  <  0.001). Small-bowel follow-through use decreased during the years (year 1 n = 213, year 5 n = 108; P < 0.001), whereas magnetic resonance imaging use increased (year 1 n  = 25, year 5 n  = 171; P < 0.001). Patients diagnosed as having Crohn disease (CD, 59%) and ulcerative colitis (58%) were more likely to have had a complete diagnostic workup than patients diagnosed as having IBD unclassified (45%). In CD, the diagnostic yield of OGD was 7.5% and the yield of ileal intubation was 13%. CONCLUSIONS: The quality of diagnostic workup in paediatric patients with IBD increased steadily between 2004 and 2009. Small-bowel imaging by magnetic resonance imaging superseded the use of small-bowel follow-through. OGD and ileal intubation contributed to a definitive diagnosis of CD.

Antitumor necrosis factor treatment for pediatric inflammatory bowel disease.

Infliximab, adalimumab, and certolizumab are monoclonal antibodies against tumor necrosis factor-α (TNFα), a proinflammatory cytokine with an increased expression in the inflamed tissues of inflammatory bowel disease (IBD) patients. Currently, infliximab is the only anti-TNF drug that has been approved for use in refractory pediatric Crohn's disease (CD). Nevertheless, adalimumab and certolizumab have been used off-label to treat refractory pediatric IBD. Over the past 10 years, anti-TNF treatment has been of great benefit to many pediatric IBD patients, but their use is not without risks (infections, autoimmune diseases, malignancies). Despite the growing experience with these drugs in children with IBD, optimal treatment strategies still need to be determined. The purpose of this review is to summarize the current knowledge on the use of anti-TNF drugs in pediatric IBD and to discuss the yet-unsolved issues.