Hillary Elwood1,2,3, Ryan S Berry1, Jerad M Gardner4,5, Sara C Shalin4,5. 1. Department of Pathology, University of New Mexico School of Medicine, Albuquerque, NM, 87125, USA. 2. Department of Dermatology, University of New Mexico School of Medicine, Albuquerque, NM, 87125, USA. 3. Pathology Associates of Albuquerque, Albuquerque, NM, 87125, USA. 4. Department of Pathology, University of Arkansas for Medical Sciences, Little Rock, AR, 72205, USA. 5. Department of Dermatology, University of Arkansas for Medical Sciences, Little Rock, AR, 72205, USA.
Abstract
BACKGROUND: Cutaneous infection with the mite Sarcoptes scabiei var. hominis is associated with epidermal and dermal changes. After noting superficial fibrin thrombi in two biopsies with scabies mites, we comprehensively reviewed the histopathologic findings in scabietic infections to determine the frequency of this finding. METHODS: Twenty five biopsies of scabies infection were retrieved from the archives of our institution; only cases containing scabietic mite parts or scybala were included. The microscopic features were documented. RESULTS: Nearly half (40%) of the cases showed fibrin thrombi within vessels of the superficial dermis. Other frequent findings included dermal eosinophils (88% of cases), epidermal spongiosis (76% of cases), lymphocyte atypia (64%), a superficial and deep infiltrate (52% of cases), dermal neutrophils (52%) and endothelial cell swelling (52%). Half of the cases contained polarizable mite elements. Less commonly encountered features included extravasated erythrocytes (44%), dermal edema (32%), pink 'pigtails'(28%), intraepidermal pustules (24%), plasma cells (20%) and vasculitis (4%). CONCLUSIONS: The pathologic characteristics of scabietic infection are wide-ranging. Spongiosis, superficial and deep inflammation, and dermal eosinophils and neutrophils are seen in the majority of cases. Superficial fibrin thrombi are not uncommon in scabietic infection, and may provide a helpful diagnostic clue when mites are not visible on initial sections.
BACKGROUND:Cutaneous infection with the mite Sarcoptes scabiei var. hominis is associated with epidermal and dermal changes. After noting superficial fibrin thrombi in two biopsies with scabies mites, we comprehensively reviewed the histopathologic findings in scabietic infections to determine the frequency of this finding. METHODS: Twenty five biopsies of scabies infection were retrieved from the archives of our institution; only cases containing scabietic mite parts or scybala were included. The microscopic features were documented. RESULTS: Nearly half (40%) of the cases showed fibrin thrombi within vessels of the superficial dermis. Other frequent findings included dermal eosinophils (88% of cases), epidermal spongiosis (76% of cases), lymphocyte atypia (64%), a superficial and deep infiltrate (52% of cases), dermal neutrophils (52%) and endothelial cell swelling (52%). Half of the cases contained polarizable mite elements. Less commonly encountered features included extravasated erythrocytes (44%), dermal edema (32%), pink 'pigtails'(28%), intraepidermal pustules (24%), plasma cells (20%) and vasculitis (4%). CONCLUSIONS: The pathologic characteristics of scabietic infection are wide-ranging. Spongiosis, superficial and deep inflammation, and dermal eosinophils and neutrophils are seen in the majority of cases. Superficial fibrin thrombi are not uncommon in scabietic infection, and may provide a helpful diagnostic clue when mites are not visible on initial sections.
Authors: Deepani D Fernando; Simone L Reynolds; Gunter Hartel; Bernard Cribier; Nicolas Ortonne; Malcolm K Jones; Katja Fischer Journal: PLoS Negl Trop Dis Date: 2021-01-06