Paradoxical heat sensation in uremic polyneuropathy.

Sensory aspects of uremic neuropathy were studied in 36 patients using clinical assessment and quantitative sensory tests (QST). The outstanding abnormality in sensory quality was perception of heat in response to low temperature stimuli. This paradoxical heat sensation was found in the foot in 42% (15) of patients, far beyond the normal prevalence of 10%. Paradoxical sensation was positively related to cold hypoesthesia (P = 0.0004) suggesting disinhibition as a possible mechanism. Paradoxical heat sensation also positively related to creatinine level (P = 0.0012). Pruritus was present in 20 patients (56%), intensity not related to any biochemical or clinical parameter. Signs of sensory polyneuropathy (PNP), based on at least two abnormal parameters in the clinical assessment or QST, were found in 39% of patients (14), of whom 11 had paradoxical heat sensation. Thus, in 4 patients (11%), this sensory aberration preceded other signs for PNP. Paradoxical heat sensation seems to be a common and often early expression of the sensory neuropathy in uremia.