Relation between vitamin D status and nonalcoholic fatty liver disease in children.

OBJECTIVES: In adults, vitamin D deficiency is common in patients with nonalcoholic fatty liver disease (NAFLD) and has been associated with the severity of histology. There are known differences between adult and pediatric NAFLD, with little data regarding the relation between vitamin D and pediatric NAFLD. The aim of the present study was to examine the relation between vitamin D levels and NAFLD in children. METHODS: Clinical and histological data were used from children ages 2 to 18 years with biopsy-proven NAFLD enrolled in the Nonalcoholic Steatohepatitis Clinical Research Network studies. 25(OH) vitamin D levels were measured from serum. Data examined included demographics, anthropometrics, laboratory markers, and liver histology. Data were analyzed using 3 categories of vitamin D level: deficient (≤ 20 ng/mL), insufficient (21-29 ng/mL), and sufficient (≥ 30 ng/mL). RESULTS: A total of 102 children were studied. There was a high prevalence (80/102, 78%) of vitamin D deficiency or insufficiency; however, there were no significant associations between vitamin D level and the histological characteristics or severity of NAFLD. Significantly higher levels of triglycerides were found in those with vitamin D deficiency (P = 0.004), but there was no association with other features of the metabolic syndrome. CONCLUSIONS: There is a high prevalence of vitamin D deficiency and insufficiency in children with biopsy-proven NAFLD; however, no association was found between vitamin D deficiency and the severity of disease on biopsies. This differs from adult NAFLD studies in which vitamin D deficiency correlates with histological severity, suggesting differences in the risk factors for or consequences of pediatric NAFLD.

Rituximab as therapy for the recurrence of bile salt export pump deficiency after liver transplantation.

Progressive familial intrahepatic cholestasis type 2 (PFIC2) results from recessive mutations in the adenosine triphosphate-binding cassette B11 gene, which encodes for bile salt export pump (BSEP). Liver transplantation (LT) is offered to PFIC2 patients with end-stage liver disease. Reports have described recurrent cholestasis in PFIC2 patients after transplantation, and this has been associated with immunoglobulin G antibodies to BSEP. High-titer anti-BSEP antibodies appear to correlate with episodes of cholestatic graft dysfunction. There is no established paradigm for treating antibody-mediated posttransplant BSEP disease. It appears to be refractory to changes in immunosuppressant medications that would typically be effective in treating allograft rejection. Taking what is known about its pathophysiology, we designed a treatment consisting of rituximab, a chimeric monoclonal anti-CD20 antibody, in combination with intravenous immunoglobulin and plasmapheresis. Using this approach, we report the successful management of 2 patients with antibody-mediated recurrence of PFIC2 after LT.