Children on chronic PN are at risk for developing iodine deficiency and resultant hypothyroidism; hence, these children should be screened for these outcomes. Further studies are needed to define the temporal onset of iodine deficiency and timing to thyroid dysfunction related to PN.

Cholestatic liver disease has long been associated with childhood rickets, secondary to impaired absorption of fat-soluble vitamin D. Elevated serum levels of fibroblast growth factor 23 (FGF23), secondary to genetic defects or tumor-induced osteomalacia, causes hypophosphatemic rickets in childhood. We present 2 infants with end-stage liver disease due to biliary atresia (BA) who developed hypophosphatemia with renal phosphate wasting. Serum FGF23 levels were elevated more than 8 times the upper limit of normal, and the older infant showed radiographic evidence of rickets. Both infants required large supplements of phosphate in addition to calcitriol. Following liver transplantation, FGF23 normalized in both patients and phosphate and calcitriol supplementation were discontinued. Immunohistochemistry revealed ectopic overexpression of FGF23 by hepatocytes in the BA liver. These observations highlight a unique cause of hypophosphatemic rickets in childhood and suggest the need for further investigation into the relationship between BA and other cholestatic disorders, and bone metabolism.

Background & Aims: Liver disease in children with Turner Syndrome (TS) is poorly understood relative to associated growth, cardiac and reproductive complications. This study sought to better characterize hepatic abnormalities in a large national cohort of youth with TS.Methods: Using electronic health record data from PEDSnet institutions, 2145 females with TS were matched to 8580 females without TS on eight demographic variables. Outcomes included liver enzymes (AST and ALT) stratified as normal, 1-2 times above the upper limit of normal (ULN), 2-3 times ULN and >3 times ULN, as well as specific liver disease diagnoses.Results: Fifty-eight percent of youth with TS had elevated liver enzymes. Patients with TS had higher odds of enzymes 1-2 times ULN (

Context Diabetes and cardiovascular diseases are common among men with Klinefelter syndrome (KS) and contribute to higher morbidity and mortality. Objective To determine if cardiometabolic-related diagnoses are more prevalent among youth with KS compared to matched controls in a large population-based cohort. Design Secondary data analysis from electronic health records Setting Six pediatric institutions in the United States (PEDSnet) Patients All youth with KS in the database (n=1,080) and 4,497 youth without KS matched for sex, age (mean 13 years at last encounter), year of birth, race, ethnicity, insurance, site, and duration of care (mean 7 years). Main outcome measures Prevalence of five cardiometabolic-related outcomes including overweight/obesity, dyslipidemia, dysglycemia, hypertension, and liver dysfunction Results The odds of overweight/obesity (OR 1.6 (95%CI 1.4-1.8)), dyslipidemia (3.0 (2.2-3.9)), and liver dysfunction (2.0 (1.6-2.5)) were all higher in KS compared to controls. Adjusting for covariates (obesity, testosterone treatment, and antipsychotic use) attenuated the effect of KS on these outcomes, however boys with KS still had 45% greater odds of overweight/obesity (CI 1.2-1.7) and 70% greater odds of liver dysfunction (1.3-2.2) compared to controls, and both dyslipidemia (1.6 (1.1-2.4)) and dysglycemia (1.8 (1.1-3.2)) were higher in KS but of borderline statistical significance when accounting for multiple comparisons. The odds of hypertension were not different between groups. Conclusions This large, population-based cohort of youth with KS had a higher odds of most cardiometabolic-related diagnoses compared to matched controls.

We characterize karyotypic and phenotypic features of a cohort of patients with Turner syndrome (TS) and lymphedema (LD). Medical records from two large TS specialized pediatric clinics were reviewed retrospectively. Seventy-one patients with TS and history of LD were identified, mean age 15.9 ± 7.71 years. Reported LD onset was in infancy in 72% of patients, with 56% (40/71) reporting LD present at birth. LD affected hands in 29% of patients, feet in 57%, and both hands and feet in 25%. 46% reported LD was a current problem, with 11% stating it was present but not a problem. 73% (52/71) of children in this cohort had the 45,X karyotype. The remainder had mosaic/complex karyotypes. 55% of children had congenital heart disease and 10% had renal anomalies. 76% were on growth hormone treatment, 52% had a history of estrogen replacement. Lymphedema is a frequently under-documented comorbidity in Turner syndrome, with limited data currently available. Analysis of a larger cohort comparing patients with TS with and without LD is underway including the role of growth hormone and estrogen replacement in LD. Given that new therapies are being developed for LD in other genetic conditions, a better understanding of LD in Turner syndrome is important for management considerations. Presentation: Monday, June 13, 2022 12:30 p.m. - 2:30 p.m.