MedGen

Barth syndrome is characterized in affected males by cardiomyopathy, neutropenia, skeletal myopathy, prepubertal growth delay, and distinctive facial gestalt (most evident in infancy); not all features may be present in a given affected male. Cardiomyopathy, which is almost always present before age five years, is typically dilated cardiomyopathy with or without endocardial fibroelastosis or left ventricular noncompaction; hypertrophic cardiomyopathy can also occur. Heart failure is a significant cause of morbidity and mortality; risk of arrhythmia and sudden death is increased. Neutropenia is most often associated with mouth ulcers, pneumonia, and sepsis. The nonprogressive myopathy predominantly affects the proximal muscles, and results in early motor delays. Prepubertal growth delay is followed by a postpubertal growth spurt with remarkable "catch-up" growth. Heterozygous females who have a normal karyotype are asymptomatic and have normal biochemical studies. [from GeneReviews]

ELANE-related neutropenia includes congenital neutropenia and cyclic neutropenia, both of which are primary hematologic disorders characterized by recurrent fever, skin and oropharyngeal inflammation (i.e., mouth ulcers, gingivitis, sinusitis, and pharyngitis), and cervical adenopathy. Infectious complications are generally more severe in congenital neutropenia than in cyclic neutropenia. In congenital neutropenia, omphalitis immediately after birth may be the first sign; in untreated children diarrhea, pneumonia, and deep abscesses in the liver, lungs, and subcutaneous tissues are common in the first year of life. After 15 years with granulocyte colony-stimulating factor treatment, the risk of developing myelodysplasia (MDS) or acute myelogenous leukemia (AML) is approximately 15%-25%. Cyclic neutropenia is usually diagnosed within the first year of life based on approximately three-week intervals of fever and oral ulcerations and regular oscillations of blood cell counts. Cellulitis, especially perianal cellulitis, is common during neutropenic periods. Between neutropenic periods, affected individuals are generally healthy. Symptoms improve in adulthood. Cyclic neutropenia is not associated with risk of malignancy or conversion to leukemia. [from GeneReviews]

Glycogenosis due to glucose-6-phosphatase deficiency (G6P) type b, or glycogen storage disease (GSD) type 1b, is a type of glycogenosis due to G6P deficiency (see this term). [from ORDO]