Anaphylactic shock due to intra‐articular injection of diclofenac etalhyaluronate sodium: A case report

BACKGROUND: Anaphylactic shock of diclofenac etalhyaluronate agent can be prolonged and recurrent. However, its reports are rare, and consequently, its method of management remains to be established. CASE PRESENTATION: A 65‐year‐old woman received an intra‐articular injection of diclofenac and hyaluronate. After 20 min, systemic urticaria and severe hypotension developed after walking. After an intramuscular adrenaline injection, she was transferred to our hospital. Despite administration of continuous noradrenaline and adrenaline, hypotension persisted. Seven hours after the joint injection, 25 mL of knee joint fluid was aspirated under ultrasound guidance. Mobilization was performed 24 h after joint injection. However, urticaria rapidly spread after standing. At 45 and 46 h after joint injection, we confirmed that no symptoms, including urticaria, recurred after walking. CONCLUSION: Anaphylactic shock due to intra‐articular injection of diclofenac etalhyaluronate is prolonged and requires extended observation. Aspiration of joint fluid may be one of the treatment options.