Lowered ultraviolet minimal erythema dose in hemiplegia.

In view of recent reports of increased tanning in hemiplegic limbs, we have investigated ultraviolet (u.v.) minimal erythema dose (MED) in hemiplegia using the bilateral comparison technique. Seven of 10 patients had a lower MED in the hemiplegic arm compared to the normal side, the mean reduction being 16% (range 0-33%, P = 0.003). No patients had a higher MED in the hemiplegic arm. We review the literature regarding other non-neurological features of hemiplegia, in particular asymmetry of temperature, oedema, and finger clubbing, and we propose a vasomotor or trophic aetiology for these findings.