Endocrine Abstracts

Introduction: Intracranial Idiopathic Hypertension (IIH) is a rare complication of testosterone therapy. It is usually benign, but may result and permanent blindness. Its diagnosis is based on a high CSF (> 25 cm H₂O) pressure, in the absence of specific causes. The androgen receptor is expressed in the human choroid plexus, and may enhance the activity of Na+/K+-ATPase, and therefore CSF secretion.

Methods: Review of the patient’s clinical record.

Results: A 24-year old female-to-male transsexual patient had been treated for 4 years with 60 mg of testosterone gel daily, using a dispenser which supplied 20 mg/pulse. He was satisfied with the treatment, his secondary male sexual characters were well developed, his hormonal levels and hematocrit were adequate and he had not suffered any adverse effects except mild acne. The availability of the testosterone dispenser was interrupted and the patient was changed to a different testosterone gel formulation but due to a dispensation error the total daily dose of testosterone was increased to 200 mg. After 2 months the patient was admitted in the Neurology Ward for the workup of an excruciating holocranial headache, poorly responding to common analgesics, which severely limited his daily activities. Tinnitus or visual disturbances were not reported. An intracranial tumor was suspected but the cranial CT scan and MNR were negative and funduscopy did not show significant oedema. Two lumbar punctures revealed CSF pressures on 36 and 29 cm H2O, but otherwise were normal. Total plasma testosterone levels were above the measurable range (> 34.6 ng/ml, normal 2.8 - 10.7 ng/ml) and hematocrit was mildly elevated (52.7%). Testosterone was withdrawn and acetazolamide 500 mg BID was prescribed for a week. The patient was asymptomatic at discharge. One month after the discharge, transdermal testosterone was reinstated, with a daily dose of 50 mg, with no adverse effects, recovery of the target hormonal levels and normal hematocrit.

Conclusions: IIH is a rare complication of testosterone therapy, which we had not previously found in our extensive experience with testosterone treated transsexual patients. In our patient it was related to accidental overdosing, but it has occasionally been reported with standard treatment. It is a potentially severe complication, which may impair the patient’s daily activities and in the worst case scenario cause permanent blindness. The risk of IIH must be considered in male transexual patients but only very rarely may result in a contraindication for gender-affirming therapy.