Progression of PTH Resistance in Autosomal Dominant Pseudohypoparathyroidism Type Ib Due to Maternal STX16 Deletions.

Context: Maternally inherited STX16 deletions that cause loss of methylation at GNAS exon A/B and thereby reduce Gsα expression are the most frequent cause of autosomal dominant pseudohypoparathyroidism type Ib (AD-PHP1B). Early identification of these disease-causing variants in the children of affected and unaffected female carriers would prompt treatment with calcium and calcitriol once parathyroid hormone (PTH) levels increase, thereby preventing hypocalcemia and associated complications.

Objective: This study aimed to determine when PTH and calcium abnormalities develop after birth if a STX16 deletion is inherited maternally.

Early-Onset Obesity: Unrecognized First Evidence for GNAS Mutations and Methylation Changes.

Context: Early-onset obesity, characteristic for disorders affecting the leptin-melanocortin pathway, is also observed in pseudohypoparathyroidism type 1A (PHP1A), a disorder caused by maternal GNAS mutations that disrupt expression or function of the stimulatory G protein α-subunit (Gsα). Mutations and/or epigenetic abnormalities at the same genetic locus are also the cause of pseudohypoparathyroidism type 1B (PHP1B). However, although equivalent biochemical and radiographic findings can be encountered in these related disorders caused by GNAS abnormalities, they are considered distinct clinical entities.

Multiple phenotypes in phosphoglucomutase 1 deficiency.

Background: Congenital disorders of glycosylation are genetic syndromes that result in impaired glycoprotein production. We evaluated patients who had a novel recessive disorder of glycosylation, with a range of clinical manifestations that included hepatopathy, bifid uvula, malignant hyperthermia, hypogonadotropic hypogonadism, growth retardation, hypoglycemia, myopathy, dilated cardiomyopathy, and cardiac arrest.

Methods: Homozygosity mapping followed by whole-exome sequencing was used to identify a mutation in the gene for phosphoglucomutase 1 (PGM1) in two siblings.

Clinical and laboratory findings in four patients with the non-progressive hepatic form of type IV glycogen storage disease.

The classic clinical presentation for type IV glycogen storage disease (branching enzyme deficiency, GSD IV) is hepatosplenomegaly with failure to thrive occurring in the first 18 months of life, followed by progressive liver failure and death by age 5 years. Although there have been two patients without apparent liver progression previously reported, no long-term follow-up clinical data have been available. We present here the clinical spectrum of the non-progressive liver form of GSD IV in four patients, and long-term follow-up of the oldest identified patients (ages 13 and 20 years).

Spontaneous pneumomediastinum in a patient with diabetic ketoacidosis: a potentially hidden complication.

A pediatric patient with diabetic ketoacidosis (DKA) was found to have a pneumomediastinum and a small pneumothorax. Because some of the signs and symptoms of pneumomediastinum may be confused with those of the patient's primary disease process, this complication may be present more frequently than has been previously described.