Pustular Psoriasis Diagnosis and Management
Histopathological Features
- Pustular psoriasis is characterized by large collections of neutrophils in the stratum corneum that are clinically apparent as pustules on an erythematous background 2
- Histologically, these pustules are sterile and represent a severe inflammatory response with neutrophilic infiltration 2, 3
- The condition may occur with or without evidence of classic plaque-type disease, indicating distinct pathophysiological mechanisms 2
Clinical Presentation and Diagnosis
- Pustular psoriasis presents in two main forms: Generalized pustular psoriasis (GPP or von Zumbusch variant) - an uncommon, severe form accompanied by fever and systemic toxicity, and Localized pustular psoriasis - typically affecting palms and soles 2
- Laboratory investigations are rarely helpful for diagnosis, which remains primarily clinical 4
- Skin biopsy may be necessary to confirm the diagnosis in atypical presentations 1
Management Protocol
Generalized Pustular Psoriasis (GPP)
- The American Academy of Dermatology recommends spesolimab (anti-IL-36 receptor monoclonal antibody) as first-line therapy for generalized pustular psoriasis 1
- Acitretin is an alternative systemic option, effective at a dose of 0.1-1 mg/kg/day, but is contraindicated in pregnancy 5
- Cyclosporine and methotrexate are also alternative systemic options for rapid control in severe cases 5
- Biologics, such as ustekinumab, may be effective for moderate-to-severe cases 1
Localized Pustular Psoriasis
- Topical corticosteroids, such as moderately potent topical corticosteroids (grade III), are recommended for symptom relief 5
- Topical coal tar and dithranol may provide some benefit 5
- PUVA (psoralens plus ultraviolet A) is considered a first-line systemic treatment with least toxicity 5
Monitoring and Follow-up
- Regular clinical review is essential for all patients on treatment, with regular blood tests, liver function tests, and serum creatinine monitoring depending on the agent used 5, 6
- Monitor for complications, including secondary infections, metabolic abnormalities, and systemic inflammation 4