Pyemotes ventricosus Dermatitis: A Case Report and an Extensive Review of Outbreaks and Clinical Cases

(1) Background: Pyemotes ventricosus dermatitis, caused by free-living mites, could be difficult to diagnose since bites are painless and ectoparasites are not visible. We present an unpublished clinical case that occurred in Italy and an extensive review of clinical cases and outbreaks of Pyemotes species. (2) Methods: Case reports and outbreaks of Pyemotes spp. were searched for on Pubmed and Embase. Epidemiological and clinical data were analysed with descriptive statistics. (3) Results: In total, we found 40 case reports and 21 outbreaks to be considered in this review. The majority of cases involved young females, occurred in summer and were observed in Europe. Dermatitis was the most common clinical manifestation. Diagnosis was mainly based on risk factors. Treatment was based on topical steroids and antihistamine drugs. Regarding outbreaks, contact with grain or feed and exposure with infested furniture were the main risk factors. The mean number of involved patients were 69, with symptoms most commonly ending within a week. (4) Conclusions: Pyemotes ventricosus dermatitis is underreported, especially in countries like Africa and Central and South-America, since disease is self-limiting and comet sign is reported in a quarter of cases. The reduction in use of pesticides in agriculture could lead to an increased exposure to Pyemotes spp. in the future.