Background : Adult-onset idiopathic hypogonadotrophic hypogonadism is a rare condition. This is a less well characterized group includes men who have no recognizable central nervous system abnormality nor other identifiable cause. They generally demonstrate age-appropriate puberty and normal secondary sexual characteristic. This is different from classic isolated gonatrophin-releasing hormone deficiency which typically presents with absent or delayed puberty.
Objectives : We report a case of adult-onset idiopathic hypogonadotrophic hypogonadism.
Methods: A 20-year-old man was referred to Endocrinology Outpatient Department for further investigation of 6-month-history of lethargy and low libido. He had no significant past medical history and was on no regular medications. He denied taking anabolic steroid. He had normal sensation of smell. He was born prematurely at a month earlier with no complication and achieved normal developmental milestone. He attained normal puberty and normal secondary sexual characteristic. He had no siblings. Family history was unremarkable. Physical examination showed BMI of 26 kg/m2and normal testicular examination ( 25mls bilaterally). Investigations revealed hypogonatrophic hypogonadism with LH of <2 IU/L, FSH of 3IU/L and testosterone of 2.7 nmol/L. He had otherwise normal anterior pituitary hormone secretions. Iron studies were normal A MRI of pituitary did not elicit any abnormality. Semen analysis revealed azoospermia.
Results: Based on the findings, a diagnosis of adult-onset idiopathic hypogonadism was made.
Conclusion : This is a rare condition only reported in few studies. The recognition of adult-onset hypogonadotropic hypogonadism in men is critical as it is a potentially treatable form of male infertility.