Tiny Troublemakers-A Comprehensive Approach to Crusted Scabies

Abstract

Background and Clinical Significance: The current paper presents a retrospective case of a 79-year-old female patient admitted to the Dermatology Clinic of Emergency City Hospital in Timisoara, Romania, in January 2022, reporting intense pruritus and burning sensation of the skin exacerbated at night. Case Presentation: The previously mentioned symptoms appeared approximately six months prior, with gradual and continuous progression. Clinical examination revealed widespread hyperkeratosis on diffuse erythematous background across the entire body, accompanied by crusted lesions predominantly on the arms and legs. Laboratory values showed elevated absolute eosinophil count as well as a positive culture swab to Staphylococcus aureus. Two incisional skin biopsies were performed. Microscopic examination in Hematoxylin-Eosin staining revealed thickened stratum corneum with numerous oval-shaped mites with exoskeleton and striations and moderate perivascular lympho-eosinophilic infiltrate in the superficial dermis, leading to a positive diagnosis of crusted scabies. Following etiological treatment, the patient's evolution was undulating and on the 10th day of hospitalization presented marked dyspnea, followed by cardiorespiratory arrest, leading to the patient's death. Conclusions: The patient's outcome could be explained by a Th2-mediated allergic response to Sarcoptes scabiei allergens, in addition to the presence of Staphylococcus aureus on the damaged skin, as dysbiosis can further support an uncontrolled Th2 reaction, leading to anaphylaxis.

Keywords: anaphylaxis; crusted scabies; hypereosinophilia; scabies.

Figure 1

Clinical presentation: (a) Hyperkeratosis with dry crusts on arms, hands and legs; (b) erythematous rash causing intense pruritus; (c,d) nail involvement (onychogryphosis).

Figure 2

Microscopic examination on Hematoxylin–Eosin-stained slides: (a) Sarcoptes scabiei mite in stratum corneum, ob. 10×; (b) intracorneal mites, eggshells, and fecal deposits (scybala), ob. 10×; (c,d): oval shaped mites of 0.2 mm length and exoskeleton with striations, ob. 40×.