From the Guidelines
Guttate psoriasis should be treated with narrow-band UVB phototherapy, which has been shown to be more effective than broadband UVB in achieving clearance and remission, with a remission rate of 38% after 1 year, as compared to 5% with broadband UVB 1.
Diagnosis and Treatment
Guttate psoriasis is a skin condition characterized by small, drop-shaped, scaly lesions that typically appear suddenly on the trunk and limbs. It often develops following a streptococcal throat infection, particularly in children and young adults.
Treatment Options
- Topical corticosteroids such as triamcinolone 0.1% or betamethasone 0.05% applied twice daily to affected areas for 2-4 weeks may be used for mild cases.
- For more widespread cases, narrow-band UVB phototherapy administered 2-3 times weekly for 6-8 weeks is effective in achieving clearance and remission 1.
- If a streptococcal infection is confirmed, a course of antibiotics like penicillin V 500mg four times daily for 10 days or azithromycin 500mg on day one followed by 250mg daily for 4 days may be prescribed.
Important Considerations
- Keeping the skin moisturized with emollients and avoiding triggers like stress, skin injury, and certain medications can help prevent flares.
- Most cases of guttate psoriasis resolve within a few weeks to months, though some patients may develop chronic plaque psoriasis later.
- The condition results from an abnormal immune response that accelerates skin cell turnover, causing the characteristic scaly patches when T-cells mistakenly attack healthy skin cells.
Monitoring and Precautions
- Regular full skin examination to monitor signs of photoaging, pigmentation, and cutaneous malignancies is necessary for patients undergoing phototherapy 1.
- Laboratory monitoring, including complete blood count, hepatic transaminases, and creatinine, should be performed at least 4 days after dosing to avoid making dosage adjustments based on transient elevations of hepatic transaminases 1.
From the FDA Drug Label
Psoriasis: Methotrexate is indicated in the symptomatic control of severe, recalcitrant, disabling psoriasis that is not adequately responsive to other forms of therapy, but only when the diagnosis has been established, as by a biopsy and/or after dermatologic consultation The diagnosis of guttate psoriasis is not explicitly mentioned in the provided drug labels.
- The treatment for severe, recalcitrant, disabling psoriasis (which may include guttate psoriasis) is methotrexate 2 or topical corticosteroids such as triamcinolone acetonide 3.
- However, it is crucial to establish the diagnosis through a biopsy and/or dermatologic consultation before initiating treatment with methotrexate.
From the Research
Diagnosis of Guttate Psoriasis
- Guttate psoriasis is characterized by scattered "drop-like" papules and plaques, accounting for up to a quarter of psoriasis cases 4
- It typically presents with an abrupt onset of numerous, small, scattered, tear-drop-shaped, scaly, erythematous, pruritic papules and plaques 5
- Sites of predilection include the trunk and proximal extremities 5
- There may be a history of preceding streptococcal infection 5, 6
- Koebner phenomenon is characteristic 5
Treatment of Guttate Psoriasis
- Topical corticosteroids and calcipotriol creams have the most evidence for efficacy as first-line therapy 4
- Phototherapy, particularly narrowband ultraviolet B (UVB), has the most robust evidence and is recommended as first-line therapy for moderate-to-severe guttate psoriasis 4, 7
- Systemic therapies, including traditional immunosuppressants, retinoids, and biologics, may be considered for patients with moderate-to-severe guttate psoriasis who fail to respond to phototherapy and topical therapies 4, 5
- Antibiotics may be recommended as supportive therapy if applicable 4
- Treatment options also include vitamin D analogues, calcineurin inhibitors, anthralin, coal tar, and tazarotene 5