HUPRA Syndrome: A Comprehensive Review Introduction HUPRA syndrome (Hyperuricemia, Pulmonary hypertension, Renal failure in infancy, and Alkalosis) is an ultrarare autosomal recessive mitochondrial disease first described in 2011. The condition is characterized by a distinctive constellation of clinical features that reflect severe mitochondrial dysfunction affecting multiple organ systems. With fewer than ten cases reported worldwide …
HPRT1 Partial Deficiency (Kelley-Seegmiller Syndrome): A Comprehensive Review Introduction HPRT1 partial deficiency, commonly known as Kelley-Seegmiller syndrome, is a rare, X-linked recessive disorder of purine metabolism caused by decreased activity of the hypoxanthine-guanine phosphoribosyltransferase (HPRT) enzyme. Unlike complete HPRT deficiency (Lesch-Nyhan syndrome), this disorder presents primarily with hyperuricemia and gout, with little or no neurological …
HPRT Complete Deficiency: A Comprehensive Medical Review Introduction HPRT complete deficiency, also known as Lesch-Nyhan syndrome (LNS), is a rare X-linked recessive inborn error of purine metabolism caused by the virtual absence or severe deficiency of hypoxanthine-guanine phosphoribosyltransferase (HPRT) enzyme activity. According to trusted medical organizations including the National Organization for Rare Disorders (NORD), the …
HOPP Syndrome: A Comprehensive Medical Review Introduction HOPP syndrome, standing for Hypotrichosis, Osteolysis, Periodontitis, and Palmoplantar keratoderma syndrome, is an extremely rare ectodermal dysplasia syndrome first described by Van Steensel and colleagues in 2002. According to trusted medical organizations including Orphanet, the National Organization for Rare Disorders (NORD), and the European Reference Networks, this condition …
HIBCH Deficiency: A Comprehensive Review Introduction 3-Hydroxyisobutyryl-CoA hydrolase (HIBCH) deficiency (OMIM #250620) is an extremely rare autosomal recessive inborn error of valine catabolism that leads to severe neurological manifestations and mitochondrial dysfunction. First described in 1982, this devastating condition has been reported in fewer than 100 patients worldwide, with most cases presenting in early infancy …
HGSNAT Deficiency: A Comprehensive Medical Review Introduction HGSNAT deficiency, also known as mucopolysaccharidosis type IIIC (MPS IIIC) or Sanfilippo syndrome type C, is a rare autosomal recessive lysosomal storage disorder caused by deficiency of the enzyme heparan-α-glucosaminide N-acetyltransferase (HGSNAT). According to trusted medical organizations including the National Institutes of Health (NIH), Orphanet, and the National …
HEM Dysplasia: A Comprehensive Medical Review Introduction HEM dysplasia, also known as Greenberg dysplasia or Hydrops-Ectopic calcification-Moth-eaten skeletal dysplasia, is an extremely rare autosomal recessive skeletal disorder first described by Greenberg and colleagues in 1988. According to trusted medical organizations including Orphanet, the National Organization for Rare Disorders (NORD), and the National Institutes of Health …