Etoricoxib-induced immune hemolytic anemia: first case presenting acute kidney failure.

BACKGROUND: Etoricoxib is a selective inhibitor of cyclooxygenase 2 used mainly to treat osteoarticular pain. Here, we report the case of a patient who developed acute kidney failure and immune hemolytic anemia after the use of etoricoxib. STUDY DESIGN AND METHODS: An 83-year-old female patient developed immune hemolytic anemia and acute kidney failure after treatment with etoricoxib for articular pain. Given the acute kidney failure, she required five hemodialysis sessions. She was discharged after 17 days. The case of immune hemolytic anemia and kidney failure was fully resolved. RESULTS: The direct antiglobulin test was not only positive for IgG but also for C3b and C3d, showing a very intense reactivity (++++). The eluate's reactivity was weaker (++) and showed no defined specificity. The investigation of unexpected antibodies in the serum of the patient showed a reactivity pattern similar to the eluate's: weak reactivity without specificity. The serum of the patient was compared to urine and plasma samples of two groups of volunteers. The indirect antiglobulin test showed only a very strong reactivity with the urine samples of the volunteers who had received etoricoxib. DISCUSSION: Considering that positive eluate is not the typical serologic profile of drug-induced immune hemolytic anemia, developing in-house techniques to show the causal link between them may be of interest to guide the treatment and avoid the empirical use of drugs. CONCLUSION: Etoricoxib must be considered as a possible cause of acute kidney failure in cases of immune hemolytic anemia.

Etoricoxib decreases subchondral bone mass and attenuates biomechanical properties at the early stage of osteoarthritis in a mouse model.

Etoricoxib, a selective Cyclooxygenase-2 (COX-2) inhibitor, is commonly used in osteoarthritis (OA) for pain relief, however, little is known about the effects on subchondral bone. In the current study, OA was induced via destabilization of the medial meniscus (DMM) in C57BL/6 mice. Two days after surgery, mice were treated with different concentrations of Etoricoxib. Four weeks after treatment, micro computed tomography (Micro-CT) analysis, histological analysis, atomic force microscopy (AFM) analysis, and scanning electron microscopy (SEM) were performed to evaluate OA progression. We demonstrated that Etoricoxib inhibited osteophyte formation in the subchondral bone. However, it also reduced the bone volume fraction (BV/TV), lowered trabecular thickness (Tb.Th), and more microfractures and pores were observed in the subchondral bone. Moreover, Etoricoxib reduced the elastic modulus of subchondral bone. Exposure to Etoricoxib further increased the empty/total osteocyte ratio of the subchondral bone. Etoricoxib did not show significant improvement in articular cartilage destruction and synovial inflammation in early OA. Together, our observations suggested that although Etoricoxib can relieve OA-induced pain and inhibit osteophyte formation in the subchondral bone, it can also change the microstructures and biomechanical properties of subchondral bone, promote subchondral bone loss, and reduce subchondral bone quality in early OA mice.