Adult-onset reversible idiopathic hypogonadotropic hypogonadism in male adult carrying a WDR11 missense mutation

Idiopathic hypogonadotropic hypogonadism (IHH) occurs mostly in childhood or adolescence and very rarely in adulthood. It is characterised by delayed onset of secondary sexual characteristics. Many genetic abnormalities have been reported in congenital IHH cases, but rarely in adult-onset IHH cases. IHH requires lifelong hormone replacement therapy; however, a few reports suggest the reversibility of this condition. In this case, after having his first child, a man in his 20s was diagnosed with gynecomastia followed by IHH. He improved with gonadotropin-releasing hormone replacement therapy and had two more children. The treatment was discontinued after 4 years, but the improvement was sustained. He had a heterozygous missense variant in WDR11 (c.2390G>A; p.Arg797His), which may play a role in adult-onset IHH reversal. Accumulation of such cases can contribute to our understanding of the pathogenesis and genetic component of IHH.