Diagnosis and treatment of bullous pemphigoid that developed twice after total knee replacement arthroplasty: a case report

Background Total knee replacement arthroplasty (TKA) is frequently performed in South Korea. Simple swelling-associated blistering around the periphery of the operative wound is a well-known adverse effect. However, in rare cases, the blisters are bullous pemphigoid (BP). Case presentation A 75-year-old male presented with knee pain that had not improved despite 5 years of medication. We performed TKA of the left knee, placing a Stryker posteriorly stabilized prosthesis. Three days later, blisters developed near the buttocks and thighs and, on day 10 after surgery, around the operative site. A skin biopsy revealed BP. Commencing on day 14 after surgery, prednisolone 10 mg was administered twice daily. The symptoms improved by 3 weeks after surgery and were healed at 4 months. After 1 year, we performed TKA of the right knee. On day 2 after surgery, as formerly, blisters developed on the buttocks and an immediate biopsy revealed BP. Commencing on day 3 after surgery, prednisolone 10 mg was administered twice daily. On day 10 after surgery, the blisters on the buttocks had improved and no blisters were observed at the surgical site. All symptoms had resolved by 2.5 months after surgery. Conclusions After TKA surgery, generalized BP may develop, diagnosed via skin biopsy. A quick diagnosis is important because early treatment can prevent symptom progression and shorten treatment.