(BMJ)—A 5-yo girl had fever, coryza, and multiple skin lesions x1 day, w/ abdominal pain and 1 episode of vomiting. Exam: low BP; multiple petechial and purpura-like lesions on limbs and face. Labs: anemia, low platelets, high CRP, renal failure, and coagulopathy. What is the dx?
Immune thrombocytopenic purpura
Henoch-Schonlein purpura
Purpura fulminans
Thrombotic thrombocytopenic purpura
Hemolytic-uremic syndrome
You are correct. Purpura fulminans is a rapidly progressive thrombotic disorder that manifests w/ disseminated intravascular coagulation, intravascular thrombosis, and hemorrhagic infarction of the skin, usually caused by Neisseria meningitidis infxn. Early manifestations can be confused w/ simple traumatic wounds or w/ other purpuric lesions, such as Henoch-Schonlein purpura, thrombotic thrombocytopenic purpura, or immune thrombocytopenic purpura. A definite dx can be established based on the rapid sequential changes. Mortality rate is high (10%-50%). This pt received prompt supportive care, blood transfusion, broad-spectrum abx, and continuous venovenous hemofiltration. She had an uneventful recovery. The necrotic skin lesions healed, and no skin grafting was required.

BMJ 2017;357:j2530

(BMJ)—A 75-yo male nursing home resident w/ hx of spinal cord injury presented w/ an itchy rash x4mo. Exam: crust and hyperkeratosis on bilateral hands and feet, w/ web space involvement. Excoriated red papules on trunk, axillae, and glans penis. Fungal scraping was negative. What is the dx?
Tinea corporis
Crusted scabies
Lichen planus
Darier disease
Eczema
You are correct. Scabies is a common ectoparasitic infestation that occurs in residents of nursing homes, day care centers, and hospitals. The crusted variant tends to affect immunocompromised and debilitated pts, who present w/ a high mite load (tens of thousands), and is extremely infectious. This pt was treated w/ permethrin 5% solution to his entire body, including web spaces, for 12h on 2-3 consecutive nights and repeated 1wk later. Close contacts in the pt’s nursing home were also treated. The pt was completely eradicated of dz after 2 cycles of tx. Oral ivermectin was not required.

BMJ 2017;357:j2912