First Case of H Syndrome in Northern Morocco: Clinical Features and Literature Overview

H syndrome is a rare multisystem genodermatosis with an autosomal recessive inheritance, characterized by cutaneous hyperpigmentation, hypertrichosis, hepatosplenomegaly, hearing loss, heart anomalies, hypogonadism, short stature, hyperglycemia, hallux valgus and flexion contractures of fingers and toes. To date, 161 cases have been reported worldwide with limited data from North Africa. Herein, we report the case of a 17-year-old Moroccan girl diagnosed with H syndrome on the basis of clinical features and molecular testing. Clinical examination revealed dysmorphic features with insulin-dependent diabetes, sensorineural hearing loss, short stature, and progressive hyperpigmented indurated skin lesions with hypertrichosis predominantly affecting the thighs and genital region, associated with flexion contractures of the fingers and toes. Genetic testing identified a homozygous pathogenic splice-site variant c.300+1G>C in the SLC29A3 gene, previously reported to be associated with H syndrome. This is the first report of this mutation from northern Morocco, highlighting regional prevalence, phenotypic variability and the challenges faced in diagnosis due to high cost and limited access to molecular testing.