In March 2012, a 43-year-old woman was referred to our psoriasis outpatient clinic because of the tenderness of the temporomandibular joints and painful swelling of the left thumb, with onset two weeks earlier. In September 2011, the woman had begun treatment with bevacizumab (540
mg every 3 weeks) for an anaplastic oligodendroglioma of the left temporal lobe; when she presented to our clinic, she had already received the 6th infusion of bevacizumab. The tumour had been partially removed at the time of diagnosis in 2001, when she was 33 years old. Before starting bevacizumab therapy, the woman had undergone several types of therapy for oligodendroglioma, such as radiotherapy, temozolomide, and fotemustine, yet with only a partial reduction of the tumour.
The woman had a history of psoriasis, which was first diagnosed when she was 15 years old. As treatment, she underwent different topical therapies (corticosteroids, vitamin D analogues) and systemic therapies (PUVA, cyclosporine). When she presented to our clinic, the psoriasis had completely cleared, without signs of nail involvement.
At the physical examination, the woman presented with severe pain in the temporomandibular joints, which greatly limited her in opening her mouth. A dactylitis of the left thumb was also observed, together with the involvement of the metacarpophalangeal joint of the same finger ().
Dactyltis of the left thumb with the involvement of the metacarpophalangeal joint of the same finger.
At this level a plain radiograph was negative, whereas magnetic resonance showed the fluid distension of the joint capsule associated with the fluid distension of the sheath of the flexor tendons (). Laboratory tests (blood count, ESR, CRP, C3, C4, ANA, rheumatoid factor, gammaglobulins, and urinalysis) were all negative or within the normal range; the only exception was positivity for anticitrullinated protein antibodies (37.8
U/mL; nv: 0–5
U/mL). Based on the clinical and instrumental findings, the woman was diagnosed with inflammatory arthritis, which was classified as “psoriatic” in accordance with CASPAR criteria [5
(a) T2 weighted MRI of the left hand shows a fluid distension of the sheath of the flexor tendons of the thumb. (b) T2 weighted MRI of the left hand shows fluid distension of the joint capsule of the 1st metacarpophalangeal.
Because bevacizumab was the only drug that the woman was taking when she developed PsA, treatment was discontinued, and a course of prednisone (25
mg/day) was started. After 15 days of corticosteroid therapy, the joint symptoms improved and there was a reduction in the dactylitis. Prednisone was tapered off and discontinued after 1 month of therapy, with a complete resolution of the joint pain and persistence of mild dactylitis.