The Psoriasis Scalp Severity Index (PSSI) can be used to evaluate and monitor a patient with scalp psoriasis. It is a modification of the Psoriasis Activity and Severity Index (PASI) scoring system.
Parameters:
(1) type of change (erythema, induation, scaling)
(2) severity of psoriatic changes
(3) percent of scalp area involved by the change
Change in Psoriasis |
Code |
erythema |
E |
infiltration, induation |
I |
desquamation, scaling |
D |
Severity of Change |
Points |
absent |
0 |
mild |
1 |
moderate |
2 |
moderate to severe |
3 |
severe |
4 |
Portion of Scalp Affected |
Points |
1 - 10% |
1 |
10 – 29% |
2 |
30 – 49% |
3 |
50 – 69% |
4 |
70 – 89% |
5 |
90 - 100% |
6 |
PSSI =
= ((points for percent of scalp area with erythema) * (points for erythema severity)) + ((points for percent of scalp area with induration) * (points for induration severity)) + ((points for percent of scalp area with scaling) * (points for scaling severity))
Interpretation:
• minimum score = 0
• maximum score = 72
• The higher the score the more severe the scalp psoriasis.
Purpose: To evaluate a patient with scalp psoriasis using the Psoriasis Scalp Severity Index (PSSI).
Specialty: Dermatology, Immunology/Rheumatology
Objective: severity, prognosis, stage
ICD-10: L40,