Loss of urinary voiding sensation due to herpes zoster

A case of sacral herpes zoster infection in a 56-year-old man with the complication of loss of urinary voiding sensation is presented. He had typical herpes zoster eruption on the left S2 dermatome, hypalgesia of the S1-S4 dermatomes, and absence of urinary voiding sensation. There was no other urinary symptom at the first medical examination. Urinary complications associated with herpes zoster are uncommon, but two types, acute cystitis and acute retention, have been recognized. No cases of loss of urinary voiding sensation due to herpes zoster have been reported. In this case, hypalgesia of the sacral dermatomes was mild compared to the marked loss of urethral sensation. This inconsistency is explained by the hypothesis that the number of urethral fibers is very small as compared to that of cutaneous fibers, therefore, urethral sensation would be more severely disturbed than cutaneous sensation.