To study clinical manifestation of peripheral neuropathy in patients with erectile dysfunction (ED) and testosterone deficiency (TD).

Testosterone is a sex hormone that plays critical roles in maintaining normal sexual function, bone mass, fat distribution, muscle mass and strength, and the production of sperm. Testosterone also plays neurotrophic roles in the central and peripheral nervous systems. TD may relate to impotence and decrease in libido in men. Frequently, patients with ED are referred to Neurology for evaluation for the possibly concomitant peripheral neuropathy (PN). However, literature on TD-induced PN is sparse.

We retrospectively reviewed the charts from our neuromuscular clinic database from January 1, 2016 to August 30, 2018 to identify patients with ED with TD and PN. Females or subjects who had a normal testosterone plasma level were excluded. Data were obtained including clinical presentations, comorbidities, body mass index, neurological examinations, and laboratory findings.

Thirteen patients (age: 56.8±13.0 years, mean ± SD; BMI: 30.2±9.6 kg/m²) were included. Their averaged testosterone-total plasma level was 205.6±81.9 (range: 34-336; normal: 348-1199 ng/dL). The presenting symptoms were numbness (10/13), tingling (9/13), pain (7/13). Abnormal neurologic examination showed stocking-glove pattern of sensory deficit (5/13), ambulatory difficulty (2/13), allodynia (1/13), foot drop (1/13), hypo- (8/13) and hyper- (3/13) tendon reflexes. Laboratory findings showed abnormally increased FSH (1/7) and estrogen (1/3) but normal other endocrine surveys including brain images. Vitamin D deficiency (7/8), elevated plasma homocysteine level (6/6), diabetes (4/7) and abnormal liver functions (1/6) were noted. Detailed results will be presented.

Clinical manifestation of PN in patients with ED in TD appears to be mild and the pattern of the PN is likely to be predominantly of paresthesia with abnormal plasma levels of Vitamin D and homocysteine and preexisting diabetes.  Recognition of its features of TD related-PN may help effectively manage the patients.