Pseudothrombophlebitis complicating childhood lyme arthritis.

Calf pseudothrombophlebitis is defined as the acute onset of nontraumatic, nonthrombotic painful swelling of the calf after knee synovitis. The name underscores the clinical similarities between this condition and "true" femoral/popliteal thrombophlebitis pointed out by Baker more than a century ago. A variety of arthritic conditions of the knee, primarily chronic, can be complicated by calf pseudothrombophlebitis. Pseudothrombophlebitis as a complication of Lyme arthritis has been mentioned in clinical reviews of the disease, but to our knowledge, no documented cases of such association were published. Furthermore, pseudothrombophlebitis in the setting of Lyme disease is particularly challenging, both from the diagnostic and therapeutic points of view.Herein, we describe three children who developed pseudothrombophlebitis as a presenting feature of Lyme disease. One of the patients is described in detail, and the clinical findings on the whole group are summarized.