Endocrine Abstracts

Introduction: Hypogonadotropic hypogonadism (HH) is a heterogenous disease caused by mutations in several genes. Based on the presence of hyposmia/anosmia it is distinguished into Kallmann syndrome and isolated HH. The prevalence of other developmental anomalies is not well established.

Methods: We studied patients with HH (29 males, 3 females, mean age 41.5), 9 with familial and 23 sporadic HH (29 congenital, 3 adult-onset), by physical examination, smell test (BSIT Sensonics), audiometry, renal ultrasound, and magnetic resonance imaging of the olfactory structures.

Results: Based on the smell test, patients were classified as normosmic (n=19, 59.4%) and hypo/anosmic (n=13, 40.6%). Hypoplasy/agenesis of olfactory bulbs was found in 38% of patients (8/21), (80% hypo/anosmic, 8.3% normosmic, P< 0.05, X²-test). Remarkably, olfactory structures were normal in 2 anosmic patients, while 1 normosmic patient presented a monolateral hypoplastic bulb. 9 of 22 patients (40.9%) presented neurosensorial hearing loss of various degrees (36.3% hypo/anosmic, 41.6% normosmic, P=NS). Renal ultrasound revealed 28.1% of cases with renal anomalies (30.7% hypo/anosmic, 26.3% normosmic, P=NS). At least one midline defects was found in 48.3% of patients (58.3% hypo/anosmic, 42.1% normosmic, P=NS): 13/31 abnormal palate (41.6% hypo/anosmic, 42.1% normosmic, P=NS), 6/31 agenesis of one or more teeth (25% hypo/anosmic, 15.7% normosmic, P=NS), 2/31 pectus excavatum (8.3% hypo/anosmic, 5.2% normosmic, P=NS), 2/31 bimanual synkinesis (8.3% hypo/anosmic, 5.2% normosmic, P=NS), 2/31 iris coloboma and absent nasal cartilage (15.3% hypo/anosmic, 0% normosmic, P=NS). Anamnestically 4/26 patients reported cryptorchidism (30% hypo/anosmic, 6.2% normosmic, P=NS).

Conclusions: Hypo-anosmia is significantly related to anatomical anomalies of the olfactory bulbs/tracts but the prevalence of other developmental anomalies, especially hearing loss, is high both in HH and Kallmann syndrome and independent of the presence of anosmia/hyposmia. From the clinical standpoint Kallmann syndrome and isolated HH should be considered as the same complex, developmental disease.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.