A unique combination of Generalised Pustular Psoriasis (GPP), Acrodermatitis Continua of Hallopeau (ACH), and psoriatic arthritis (both axial and peripheral) in a young male – a case-based review of literature

Abstract Background The simultaneous occurrence of generalised pustular psoriasis (GPP), acrodermatitis continua of Hallopeau (ACH), and Psoriatic arthritis (PsA) in the same patient is infrequently documented in the literature. However, diagnosis of PsA, especially axial PsA, is often missed in everyday clinical practice. Case A 21-year-old male presented with a generalised scaly, pus-filled rash affecting his face, chest, back, and upper and lower limbs. He also reported experiencing inflammatory polyarthritis in his toes and fingers for the past month, along with right-sided lower back pain during this same period. Additionally, he had a history of intermittent pustular rashes on his nails over the past year, worsening during this episode. Examination revealed a generalised pustular psoriasis rash, with a Psoriasis Area Severity Index (PASI) score of 38.5. There was also evidence of nail psoriasis with (ACH) and a nail psoriasis severity index (NAPSI) of 48/80. His Disease Activity Index for Psoriatic Arthritis (DAPSA) score was recorded at 34. He also had hepatitis and neutrophilic leukocytosis. Following the initiation of therapy with Adalimumab and methotrexate, he experienced significant improvement in both cutaneous and musculoskeletal symptoms, and his systemic features related to hepatitis were also resolved. Conclusion This case underscores that axial PsA can be a hidden component of severe pustular psoriasis and highlights the critical need for a multidisciplinary approach.