{Reference Type}: Journal Article
{Title}: Juvenile polyposis syndrome in children: The impact of SMAD4 and BMPR1A mutations on clinical phenotype and polyp burden.
{Author}: Cohen S;Yerushalmy-Feler A;Rojas I;Phen C;Rudnick DA;Flahive CB;Erdman SH;Magen-Rimon R;Copova I;Attard T;Latchford A;Hyer W;
{Journal}: J Pediatr Gastroenterol Nutr
{Volume}: 79
{Issue}: 1
{Year}: 2024 Jul 27
{Factor}: 3.288
{DOI}: 10.1002/jpn3.12257
{Abstract}: <B>OBJECTIVE: </B>A constitutional disease-causing variant (DCV) in the SMAD4 or BMPR1A genes is present in 40%-60% of patients with juvenile polyposis syndrome (JPS). The aim of this study was to characterize the clinical course and polyp burden in children with DCV-positive JPS compared to DCV-negative JPS.<BR><B>METHODS: </B>Demographic, clinical, genetic, and endoscopic data of children with JPS were compiled from eight international centers in the ESPHGAN/NASPGHAN polyposis working group.<BR><B>RESULTS: </B>A total of 124 children with JPS were included: 69 (56%) DCV-negative and 55 (44%) DCV-positive (53% SMAD4 and 47% BMPR1A) with a median (interquartile range) follow-up of 4 (2.8-6.4) years. DCV-positive children were diagnosed at an older age compared to DCV-negative children [12 (8-15.7) years vs. 5 (4-7) years, respectively, p < 0.001], had a higher frequency of family history of polyposis syndromes (50.9% vs. 1.4%, p < 0.001), experienced a greater frequency of extraintestinal manifestations (27.3% vs. 5.8%, p < 0.001), and underwent more gastrointestinal surgeries (16.4% vs. 1.4%, p = 0.002). The incidence rate ratio for the development of new colonic polyps was 6.15 (95% confidence interval 3.93-9.63, p < 0.001) in the DCV-positive group compared to the DCV-negative group, with an average of 12.2 versus 2 new polyps for every year of follow-up. There was no difference in the burden of polyps between patients with SMAD4 and BMPR1A mutations.<BR><B>CONCLUSIONS: </B>This largest international cohort of pediatric JPS revealed that DCV-positive and DCV-negative children exhibit distinct clinical phenotype. These findings suggest a potential need of differentiated surveillance strategies based upon mutation status.