Severe Keratoderma Blenorrhagicum simulating Psoriasis in reactive Arthritis: A case report

ABSTRACT

Introduction@#Severe keratoderma blenorrhagicum (KB) is a rare cutaneous manifestation of reactive arthritis (ReA) which can be indistinguishable from psoriasis, making the diagnosis challenging. This is a case of reactive arthritis in a 33-year-old female presenting with disabling, painful oligoarthritis which was accompanied by generalized pustular and scaly rashes simulating psoriasis.@*Case@#A 33-year-old female, Filipino, single with no known co-morbidities presented with disabling, painful oligoarthritis which was accompanied by generalized pustular and scaly rashes of two weeks duration. Her symptoms were preceded a few days earlier with a transient episode of conjunctivitis. She also reported having recently received treatment for “urinary tract infection”. There were generalized hyperkeratotic papules with areas of desquamation overlying erythematous skin involving the scalp, hairline, trunk, and extremities including palms and soles, with onycholysis on all digits. The right wrist and both ankles were warm, swollen and tender, with dactylitis involving most toes. Dermatology consult concurred with the diagnosis of keratoderma blenorrhagicum associated with reactive arthritis, over psoriasis or psoriatic arthritis, and she was started on prednisone 60 mg/day; methotrexate (MTX) 20 mg/week and folic acid were added a week later. With dramatic resolution of both skin and joint involvement, prednisone was tapered to 10 mg/day over the next three weeks and MTX was maintained at 15 mg/week, with no rebound nor recurrence of symptoms.@*Conclusion@#Severe KB is a rare cutaneous manifestation of ReA which can be indistinguishable from psoriasis. The acute onset of symptoms, recent history of eye inflammation and genitourinary tract infection strongly favored ReA over psoriasis. A further hallmark of KB is the presence of sterile pustules on the palms and soles. Histologically, KB has more numerous pustules and massive hyperkeratosis compared to psoriasis. Moreover, the dramatic response to systemic steroids, without rebound nor recurrence upon steroid taper or discontinuation favors KB over psoriasis.