Impetigo

Common and contagious, particularly amongst children.

Strep., Staph. or combination.


Bullous or non-bullous forms

Self-limiting, but may last weeks or months.

Post-strep. g.nephritis may following acute infection, but usually resolves completely without Rx

Rheumatic fever has not been reported.

Serology not routine, but:

- ASO titre doesn't increase; 

- anti-DNase B increases to high levels => best indicator of Strep. impetigo

Bullous

- usually due to Staph. epidermolytic toxin

- lesions can heal with hyperpigmentation on black skin

- regional lymphadenopathy uncommon

Non-bullous

- satellite lesions beyond periphery are common

- regional lymphadenopathy common

Recurrent impetigo is usually caused by Staph. aureus

--> Rx Bactroban ung to nares bd for 5 days

Rx

- Bactroban ung 2% = as safe and effective as oral erythromycin

- Isolate children until Rx commenced

- penicillin - Diclox

- cephalosporin - Keflex

- macrolide - EES

- often require 10-day course (5-day minimum)

- erythromycin less effective
- consider hot-washing bed linen and clothing that will tolerate this