Dermatology Index of Disease Severity (DIDS)

 

Diseases included:

(1) psoriasis

(2) dermatitis

 

If more than one skin condition is present, each should be assessed separately.

 

Body Surface Area (BSA) Involvement

 

Body Region	Percent of BSA
palm	about 1%
face alone	5%
head and neck	10%
both arms	20%
entire trunk (chest, abdomen, back), excluding buttocks	30%
both legs including buttocks	40%

 

Guidelines:

(1) active disease dispersed over a region should be mentally compressed into a single confluent area of involvement; a widely dispersed disease may actually involve only a small percent of body surface area

(2) only inflammatory disease active at the current visit should be evaluated

(3) areas of post-inflammatory hyperpigmentation or scarring are not included

 

Functional Limitations

 

Performance of activities of daily living or functioning is the second component of staging in the DIDS.

(1) related to the active cutaneous disease as observed today

(2) does not utilize historical restrictions

(3) does not include restriction due to associated processes such as arthritis

 

moderate functional limitation:

(1) clearly reduced or great difficulty in activities

(2) does not require either mechanical or human assistance to perform task

 

severe functional limitation:

(1) unable to perform task without human or mechanical assistance

 

Staging

Functional Impairment	Body Surface Involveed	Disease	Stage
none	none	none	0
none	<= 5%	limited	I
none	5.1 to 19.9%	mild	II
mild to moderate	20 to 90%	moderate	III
severe	> 90%	severe	IV

 

Functional Impairment involves functional limitation secondary to hand, foot or mucous membrane involvement.

(1) moderate: no external mechanical and/or human assistance is required

(2) severe: external mechanical and/or human assistance is required,