Case description
A 23 year-old man complained of a 6 month history of generalized
pruritus and hyperkeratotic, crusted, fissured and scaly plaques
localized in axillary folds, back, periumbilical skin and flexor surface
of the knees (Figure 1). He also had multiple erythematous papules and
excoriations due to scratching in trunk and extremities. Microscopic
examination of skin scraping revealed multiple mites, confirming the
diagnosis of crusted scabies ( Figure 2). Permethrin and ivermectin were
administered, but during hospitalization day 3 the patient presented
fever (38°) and numerous non follicular pustules over erythematous
plaques on trunk and extremities. A biopsy was performed and findings
were consistent with acute generalized exanthematous pustulosis (AGEP).
Ivermectin was discontinued and permethrin regimen was completed with
satisfactory evolution after 2 weeks (Figure 3 ).
Even though ivermectin is not FDA-approved for this use, in June 2019
the WHO added ivermectin to the 21st WHO Essential Medicines List. AGEP
is not a common adverse effect of ivermectin. As Scabies remains a
public health priority globally, this case highlights the importance of
knowing possible reactions to frequently used medications and of novel
therapeutics that serve as alternatives when it comes to scabies
management.
Conflicts of interest: None declared.