Triple metal-hypersensitivity in the patient with knee prosthesis: a rare case

Case presentation A 70-years old healthy male patient presented in our clinic with a recurrent swelling, redness and limitation of movement of his right knee. Clinical examination and laboratory findings showed no evidence of bacterial infection of the joint. The patient had no other complaints. According to the clinical history the patient received titanium prosthesis of the right knee in 2009. One year later he developed swelling, redness and limitation of movement of this joint. The patient reported also about a skin patch test that was performed and was positive for titanium. However there is no documentation available. In 2011 the prosthesis of the right knee was replaced by a CoCrMo/FeCrNiMnMoNbN/UHMWPE knee prosthesis due to persistent signs and symptoms. During the initial period of 6 months the patient reported to be free of complaints, but after this period he developed symptoms again. A CT-Scan of the right knee was unremarkable. The new skin patch test was positive for cobalt(II)chlorid (CoCl2) and potassium dichromate (K2Cr2O7). Five months later the skin patch test was repeated, but no reaction to CoCl2 or K2Cr2O7 was seen. The diagnosis remained questionable.