Endocrine Abstracts

Introduction: Bardet-Biedl syndrome (BBS) is a rare autosomal recessive genetic disorder involving hypogonadism manifested by cryptorchidism, micropenis and/or delayed puberty

Observation: We report the case of a 13 year old child, who was consulted for obesity and whose physical examination showed major signs of SBB: global obesity, polydactyly, learning difficulties and visual disorders. Genital examination revealed a 1 cm genital tubercle with a single orifice and two genital swelling without palpable gonads. Biological investigations revealed hypogonadotropic hypogonadism, corticotropic insufficiency, low AMH with a non-stimulable HCG test and a 46XY male karyotype. Pelvic MRI did not show any gonads or internal genitalia but noted ectopy and malrotation of the right kidney. The diagnosis of a testicular regression syndrome is very likely in this case. At the fundus photography: presence of bilateral retinal dystrophy with high myopia. At the hypothalamohypophyseal level: a strong pituitary hypoplasia was objectified.

Discussion: BBS is a rare autosomal recessive multisystem ciliopathy. The incidence of BBS is 1 in 150,000–160,000 in Europe and North America. BBS is caused by a dysfunction of the gene coding for proteins that are implicated in the function of the primary cilia and in important signaling pathways. The core features of the syndrome include retinal degeneration, obesity, polydactyly, cognitive impairment, renal anomalies and urogenital malformations. To date, pathogenic variants in 26 genes have been shown to be involved in the molecular basis of this rare ciliopathy. To our knowledge, only one study conducted on 11 children with BBS found among them 7 cases of pituitary abnormalities, 4 of which showed hypoplasia. While no association with a testicular regression syndrome has been described. This makes our patient the first described association of these 3 pathologies.