OBJECTIVETo explore the mechanism of erectile dysfunction (ED) with testosterone deficiency and discuss the feasibility of long-term testosterone replacement therapy (TRT) by observing a case of ED with testosterone deficiency treated by TRT for 65 months.

METHODSWe treated an ED patient with testosterone deficiency by TST for 65 months, and evaluated the therapeutic effects by analyzing his IIEF-5 score, dynamic changes in testosterone, PSA, hemoglobin and red blood cell count, and adverse events.

RESULTSThe patient was a 46-year-old man, with an IIEF-5 score of 7, baseline serum total testosterone (TT) of 2.79 ng/ml, and no response to phosphodiesterases-5 inhibitors (PDE5i). He was diagnosed with late-onset hypogonadism (LOH) and treated by TRT: testosterone undecanoate at 80 mg bid po for the first 2 weeks and then at 40 mg bid po. Two months after medication, the TT level was increased to normal (3.45 ng/ml), and physical fitness and anxiety symptoms were markedly improved, with no significant improvement in sexual function. Then we administered PDE5i on demand in addition, which elevated his IIEF-5 score to > 21. The combined medication of TRT and on-demand PDE5i lasted for 45 months followed by TRT alone for another 18 months. The patient was restored to normal penile erection and sexual satisfaction, with the IIEF-5 score remaining at > 21. Regular follow-up revealed no significant abnormalities in the testosterone level, PSA, and routine blood tests.

CONCLUSIONTRT enhances the effect of PDE5i in the treatment of androgen deficiency-induced ED, and long-term TRT is safe and effective for androgen deficiency.