Classical scabies is a cutaneous disease characterized by an intense, pruritic rash. The scabies mite, Sarcoptes scabiei, localizes to skin-fold areas of the body. Crusted scabies is a manifestation of the disease, more common in immunocompromised individuals, and has been observed following systemic therapeutic medications that weaken the immune system. The disease leads to uncontrolled mite proliferation in the skin, characterized by areas of plaques with a parakeratotic crust. Crusted scabies is rare, with limited cases reported in the literature and, consequently, often associated with a delayed diagnosis and worsening of the condition. This case report discusses a 70-year-old male presenting with a two-year history of a pruritic rash on the neck, trunk, arms, and legs, which later progressed to hyperkeratotic plaques and was diagnosed as crusted scabies. This case underscores the importance of a thorough physical examination and a broad differential diagnosis, and consideration of scabies, especially in pruritic rashes unresponsive to various therapies.
Hassevoort et al. (Thu,) studied this question.