Hidrotic Ectodermal Dysplasia (Clouston Syndrome): A Comprehensive Review Introduction Hidrotic ectodermal dysplasia (HED), also known as Clouston syndrome or hidrotic ectodermal dysplasia type 2 (HED2), is a rare autosomal dominant genodermatosis characterized by a distinctive triad of clinical findings: partial-to-complete alopecia, nail dystrophy, and palmoplantar hyperkeratosis. Unlike the more common hypohidrotic ectodermal dysplasia (HED), which …
Heterotaxy Syndrome (Situs Ambiguous): A Comprehensive Review Key Takeaway Heterotaxy syndrome is a spectrum of laterality (left–right) defects in which thoracic and abdominal organs are abnormally arranged, typically with complex congenital heart disease and splenic anomalies (asplenia or polysplenia). Early recognition, multidisciplinary management, and lifelong follow‑up are essential because morbidity and mortality are driven by …
Hemitruncus Arteriosus: A Comprehensive Review Introduction Hemitruncus arteriosus, also known as anomalous origin of one pulmonary artery from the aorta (AOPA), is a rare congenital cardiovascular malformation in which one branch pulmonary artery (either right or left) arises anomalously from the ascending aorta while the other pulmonary artery maintains its normal origin from the main …
Hemi 3 Syndrome: A Comprehensive Review Introduction Hemi 3 syndrome is an extremely rare congenital neurodevelopmental disorder characterized by a distinctive constellation of four cardinal features: hemihypertrophy (overgrowth of one side of the body), hemihypaesthesia (decreased sensation on the affected side), hemiareflexia (absent reflexes on the affected side), and scoliosis. First described by Nudleman, Andermann, …
Heller Syndrome (Childhood Disintegrative Disorder): A Comprehensive Review Introduction Childhood Disintegrative Disorder (CDD), also known as Heller syndrome or dementia infantilis, is an extremely rare neurodevelopmental disorder characterized by a period of apparently normal development for at least two years, followed by a profound and often irreversible regression in language, social, and adaptive functioning. Originally …
Heiner Syndrome: A Comprehensive Review Introduction Heiner syndrome (HS), also known as cow’s milk-induced pulmonary hemosiderosis or milk-induced pulmonary disease, is a rare non-IgE-mediated food hypersensitivity disorder that primarily affects infants and young children. First described by Dr. Douglas C. Heiner in 1962, the syndrome is characterized by chronic respiratory symptoms, pulmonary infiltrates on chest …
Hecht-Beals Syndrome: A Comprehensive Review Introduction Hecht-Beals syndrome, also known as congenital contractural arachnodactyly (CCA), represents a rare autosomal dominant connective tissue disorder that was first described by Beals and Hecht in 1971. The syndrome is characterized by a distinctive constellation of clinical features including multiple joint contractures, arachnodactyly (long, slender fingers and toes), kyphoscoliosis, …