Impetigo neonatorum, also known as bullous impetigo of the newborn, is an acute infectious suppurative skin disease mainly characterized by bullae in newborns, with rapid onset and high contagiousness.


Causes

Pathogenic bacteria are coagulase-positive staphylococcus aureus of bacteriophage group II, mostly type 71.

The source of infection is mainly from medical staff and mothers. In the epidemic of this disease, staphylococcus aureus can be isolated not only in medical personnel, but also in clothes, quilts, air, and dust.


Signs and Symptoms

Impetigo neonatorum often occurs in 4 - 10 days old neonates, with high contagiousness. Skin lesions occur mainly in exposed areas, such as face and hands, as well as in the trunk and limbs. Palms and soles are often not involved. Sometimes lesions also occur in the mucous membrane or fingers, causing purulent onychia or paronychia. Systemic symptoms are not obvious initially. With the progression, patients may present with fever, body temperature up to 39 °C, diarrhea, pneumonia, nephritis, meningitis, and even sepsis, leading to death.

Skin lesions are pinhead sized to pea sized red spots initially, and blisters occur and enlarge rapidly, with inflammatory red halos, with thin fragile wall. Fluid in the bullae turns turbid in 1 – 2 days, or yellow pus occurs in the bottom of blisters. Most bullae are purulent. Bullae are very full initially but loose after gradual expansion. After the rupture of bullae, the flushing smooth erosions are exposed, and then thin scabs are formed. Bullae can occur in the neighboring areas, and wide erosions may occur, resembling pemphigus.


Histopathology

Bullae under the stratum corneum in the epidermis are present. The blister fluid contains many neutrophils and cocci, and spongiosis and many neutrophil infiltrations are visible in the stratum spinosum in the bottom of bullae. Non-specific inflammatory changes are present in the upper dermis.


Diagnosis

On the basis of clinical findings such as purulent bullae in neonates, diagnosis is not difficult.


Treatment

Systemic treatment regimen is early use of antibiotics, such as penicillin, erythromycin, and cephalosporins. Supportive care may be necessary, including blood transfusion or intramuscular gamma globulin.

Topical treatment can be applied with mupirocin ointment, fusidic acid ointment, or 0.5% - 1% neomycin emulsion.