Methods
Laboratory tests such as complete blood count, biochemistry, and urine
analysis were within normal ranges. A punch biopsy of the knee lesion
was obtained with a differential diagnosis of psoriasis and PRP. The
histopathological study revealed a psoriasiform epidermal hyperplasia
with alternating hyperorthokeratosis and parakeratosis in horizontal and
vertical directions. Additionally, there was hypergranulosis, mild
spongiosis, and moderate superficial perivascular infiltration, which
were more indicative of pytriasis rubra pilaris (PRP) (Figure 2). Based
on clinicopathologic correlation, the patient was diagnosed with type
III juvenile PRP. Treatment with topical corticosteroid and tacrolimus
0.1% ointment was initiated. Unfortunately, the disease was progressive
and there was no response to topical treatment. After discussing
systemic therapy options with the parents, cyclosporine A (CsA) 25 mg
daily (2.5 mg per kg) was initiated, with regular monitoring of blood
pressure and electrolytes.