Scabies and nocturnal pruritus: preliminary observations in a group of African migrants

Introduction: Pruritus of scabies is due to a type IV T cell-mediated reaction to the mite's saliva, eggs, excrements and other products released by the mite during its life cycle. Movements of the mite also induce pruritus. According to the literature, scabies pruritus has higher frequency and intensity at night. Methodology: In this short communication we present the results of a survey on nocturnal pruritus in a group of African migrants with scabies. A questionnaire was given to 36 patients: “Is your pruritus more severe at night?” and “Do you wake up from the sleep because of pruritus?”. Results: The answer to the first question was “yes” in 13/18 patients (72.2%) visited from October 2018 to February 2019, and in 6/18 patients (33.3%) visited from May to September 2019. The answer to the second question was “yes” in 11/18 patients (61.1%) of the first group and in 5/18 patients (27.7%) of the second group. Conclusions: It is possible that nocturnal pruritus in scabies is due to the temperature of the skin surface: when it is high, because of the use of pajamas, heavy sheets and blankets (from October to February), pruritus increases; when the skin's temperature is low, as in the summertime, when people usually sleeps without blankets, with light sheets and pajamas or not having a stitch on, pruritus is less frequent and severe. These conclusions must be confirmed by studies based on larger groups of patients.