Guillain–Barré syndrome is associated with ixekizumab in a patient with pustular psoriasis

Dear Editor, We report a case of Guillain–Barré syndrome (GBS) following IL-17A inhibitor ixekizumab in a pustular psoriasis patient. A 29-year-old male patient suffered from generalized desquamative rash for 7 years and was treated with topical carboplatin ointment and a ‘hormone-containing ointment’ (unclear). Forty-two days before administration, the patient experienced an increase in systemic erythema and was diagnosed with pustular psoriasis. He received ixekizumab 160 mg subcutaneous injection without topical ointments. One week later, the pustular psoriasis was markedly improved. However, after 10 days of ixekizumab, the patient developed weakness in both lower extremities, making it difficult for him to walk without assistance. The patient experienced worsening of weakness and muscle pain in the lower extremities, with radicular back pain in the following 2 weeks. He denied receiving any recent vaccines or experiencing antecedent infections in the past 2 months. Physical examination revealed a body temperature of 36.6°C, pulse rate of 121/min, moon-shaped face, central obesity and subcutaneous purple striae on the abdomen and thigh. In addition, diffuse desquamative erythema was observed throughout his body (Fig. 1). The muscle tension of the extremities was normal, muscle strength of both upper extremities was grade 5, muscle strength of both lower extremities was grade 3, pain sensation was reduced below spinal level T4 and tendon reflexes of both lower extremities were reduced.