Background: Kallmann syndrome (KS) is a rare clinical entity, characterized by the association of hipogonadotropic hypogonadism and hypo/anosmia, with an estimated prevalence of 1:8000 in males and 1:40 000 in females.
Method: Retrospective study of cases of KS diagnosed in paediatric age. Genetic analysis was performed by PCR and DNA sequencing of KAL1, FGFR1, GNRHR, GNRH1, PROK2, PROKR2, KISS1R, TAC3, TACR3, and FGF8 genes.
Results: Total of seven cases, 6 (85%) males. Median age at diagnosis was 16.15 years. All were referred to a tertiary Paediatric Endocrinology Outpatient Hospital due to pubertal delay, except case 6 (diagnosis made by genetic study after his brothers diagnosis). Results are summarized in Table 1. All patients, except case 6, are treated with sex hormones.
|Decimal age at diagnosis||16.15||17.9||15.77||16.52||17.09||10.83||13.6|
|Presentation||Primary amenorrhoea||Pubertal delay||Pubertal delay||Pubertal delay||Pubertal delay||Screening||Pubertal delay short stature|
|Family history||Constitutional delay of puberty||None||None||None||None||Brother: KS||None|
|Basal LH and FSH||Low||Low||Low||Low||Low||Low|
|MRI olfactive bulbs||Absent||Absent||Hypoplasia||Absent||Absent||Absent|
|Genetic analysis||Without mutation||KAL1 deletion of exon 1, c.67_92del26, p.Leu23fsX54||FGFR1 missense mutation (p.S96C)||Without mutation||KAL1 whole gene deletion||KAL1 whole gene deletion||FGFR1 frameshift mutation (p.V460SfsX3)|
|Other malformations||Bilateral deafness||Bilateral cryptorchidism, renal agenesis||Bilateral cryptorchidism, right deafness||Cleft lip||Renal agenesis||Bilateral cryptorchidism||None|
Conclusion: The diagnosis of KS is mainly done during adolescence or adulthood because of incomplete or absent pubertal development. The sensitivity of molecular testing is only about 30%, however we identified mutations in 71% of our patients. Despite the availability of genetic testing the diagnosis is still mainly based on clinical findings. So the authors emphasize that it is essential take into account the associated malformations that may coexist in KS as well as assessment of the olfaction, often undervalued by patients.
20 - 22 Sep 2014
European Society for Paediatric Endocrinology