Unilateral anterior uveitis complicating zoledronic acid therapy in breast cancer

We report the first case of severe unilateral anterior uveitis in a patient with breast cancer and an intraocular lens. Following zoledronic acid infusion, the patient developed severe and dramatic right eye pain with decreased visual acuity within 24 hours and was found to have a fibrinous anterior uveitis of moderate severity The patient was treated with topical prednisone and atropine eyedrops and recovered slowly over several months.Internists, oncologists, endocrinologists, and ophtalmologists should be aware of uveitis as a possible complication of zoledronic acid therapy. Patients should be instructed to report immediately to their physicians and treatment with topical prednisone and atropine eyedrops should be instituted immediately at the onset of symptoms. This report documents anterior uveitis as a complication of zoledronic acid therapy. This reaction could be an idiosyncratic one but further research may shed more light on the etiology.Bisphosphonates are very widely used the the treatment of metastatic bone disease and osteoporosis. They are structurally analogues to pyrophosphates. They inhibit hydroxyapatite crystal development and dissolution by affecting the ionic makeup of the hydration layer that surrounds the crystals in suspension [1]. They also inhibit osteoclasts. They are very commonly used for osteoporosis and for cancer patients with metastatic bone disease. The most commonly used bisphophonates are etidronate, clodronate, pamidronate, alendronate and more recently zoledronic acid. Zoledronic acid is generally very well tolerated. General side effects of bisphosphonates include transient low-grade fever, fatigue, arthralgia or myalgia, nausea, increased bone pain, fluctuations in serum ion levels (calcium, magnesium, and phosphorus), and occasional elevations in serum creatinine [2].Severe anterior uveitis has been reported with alendronate [3-5] and pamidronate [6-8]. One recent case report described uveitis as a complication of zoledroni