Shwachman-Diamond syndrome and type 1 diabetes mellitus: more than a chance association?

Shwachman-Diamond syndrome is a rare clinical condition consisting of exocrine pancreatic dysfunction, various degree of pancytopenia, and metaphyseal dysplasia. The majority of Shwachman-Diamond syndrome cases result from mutations in the Shwachman-Bodian-Diamond Syndrome gene. To date, type 1 diabetes mellitus has only been reported in 4 independent cases presenting with Shwachman-Diamond syndrome, 3 of them with molecular confirmation of the diagnosis. We describe 2 unrelated patients with clinical and molecular features typical of Shwachman-Diamond syndrome and type 1 diabetes mellitus. In addition, we report the occurrence rate of type 1 diabetes mellitus in the Italian registry for Shwachman-Diamond syndrome, which is low (3.23%) but increased at least 30-fold over the type 1 diabetes mellitus occurrence rate in the general population. No evidence of a direct correlation between Shwachman-Diamond syndrome and type 1 diabetes mellitus have been reported, therefore the presence of both diseases in the same patient might be a chance association, however we suggest that the defects in immune regulation of Shwachman-Diamond syndrome might play a role in the development of type 1 diabetes mellitus.

IBD and IBD mimicking enterocolitis in children younger than 2 years of age.

Inflammatory bowel disease (IBD) is uncommon in children younger than 2 years of age. The criteria for differentiating IBD from other diseases with similar clinical presentation is unclear. We describe 16 patients who, between 1984 and 2004, received a histological diagnosis of IBD during the first two years of life. Six patients presented with histological Crohn's disease, eight with ulcerative colitis and two with indeterminate colitis. The median age at diagnosis was 125 days (range 1 day to 18 months) and the medium follow up was 89 months (range 65 days to 20 years). The disease appeared to be very severe: four children (25%) underwent total parenteral nutrition (TPN), two received colectomy (12.5%) and three patients died. Many of the patients required an aggressive, multidrug, immunosuppressive approach (azathioprine [AZA], Infliximab, thalidomide, cyclosporine A). One child presented with a hypogammaglobulinaemia without any specific immunodeficiency, while in the other patients, Wiskott-Aldrich syndrome (WAS) (4 cases) and chronic granulomatous disease (CGD) (2 cases) were identified. In 6/16 cases, allergic colitis was first considered; these cases initially underwent cow's milk protein-free diet as the only therapy before IBD was finally diagnosed. In conclusion, early IBD has a severe prognosis and often needs an aggressive therapeutic approach. Furthermore, an improper diagnosis of allergic colitis might cause an important diagnostic delay. Some severe immunodeficiencies, such as WAS and CGD, may represent a problem in terms of differential diagnosis and might be wrongly diagnosed as very early onset IBD.