Editors

AlexanderSalava

Impetigo and other Pyoderma

Impetigo spreads easily in the family, day-care centre and school.
Remember the possibility of post-infectious glomerulonephritis in streptococcal impetigo.

Children are most commonly affected.
Streptococcal infection typically makes crusts or small ulcerations; staphylococcal infection tends to make blisters (pictures 1 2).
"Pemphigus neonatorum" (picture 3) in infants is actually impetigo. The infection is caused by Staphylococcus aureus phage type II.
The crusts usually appear in the surroundings of the nostrils (picture 4), on the chin (picture 5), and generally on the face (pictures 6 7).
Thick crusts are characteristic.

Primary herpes simplex infection may resemble impetigo.
Ringworm (tinea corporis)
If impetigo tends to recur in the scalp and neck consider the possibility of head lice.

Staphylococcus aureus
Group A beta-haemolytic streptococci (picture 8)
Eczema (picture 9) may predispose the skin to impetigo.
The infection usually spreads by autoinoculation.
Recurrences are often caused by bacteria remaining in the nostrils from where they are re-spread by fingering of the nose.

Treatment is started on the basis of the clinical presentation.
If the disease is confined to a small area the treatment consists of soaking the crusts so that they are detached, and applying an antimicrobial ointment (fusidic acid Interventions for Impetigo or a combination of neomycin and bacitracin).
If the disease is more widespread (> 6 cm² ) use a systemic antimicrobial effective against S. aureus, primarily cephalexin Systemic Antibiotics in the Treatment of Impetigo in Children or flucloxacillin 750-1 000 mg 3 times daily. Duration of treatment is usually 7-10 days. Patients with cephalosporin allergy can be treated with clindamycin.
If the patient has eczema a topical preparation containing a glucocorticoid and an antimicrobial agent should be used together with systemic antimicrobials until the skin is intact.
Do not forget further treatment of the eczema.
The most common reasons for poor response to treatment
- The diagnosis is incorrect. The patient has scabies, lice, or ringworm.
- The crusts have not been soaked and removed. The bacteria can survive under crusts.
- The underlying eczema has not been treated.
- The nostrils serve as reservoir for bacteria (apply neomycin-bacitracin or fusidic acid ointment into the nostrils. Mupirocin should not be used for this disease as its use should be limited to the eradication of methicillin-resistant Staphylococcus aureus).