Diagnostic Approach to Skin Eruptions in Children

Clinical Evaluation

The American Academy of Pediatrics recommends that the history should specify the age of onset of lesions (before 6 months suggests mastocytosis or congenital atopic dermatitis) 1
The distribution of lesions (flexural areas for atopic eczema, trunk and extremities for mastocytosis) is an essential clinical element to identify, as suggested by the British Medical Journal 2, 1
The presence of pruritus and scratching (a mandatory criterion for atopic eczema) should be assessed, according to the British Medical Journal 2, 3
Family history of atopy (asthma, hay fever) is a crucial factor to consider, as recommended by the British Medical Journal 2, 3
The British Medical Journal suggests that triggers (temperature changes for mastocytosis, irritants for eczema) should be identified 1, 4
Systemic symptoms (fever, flushing, diarrhea) should be evaluated, as recommended by the American Journal of Clinical Dermatology 1

The British Medical Journal proposes that the diagnostic criteria for atopic dermatitis (eczema) include pruritus plus at least three of the following: involvement of flexural areas, personal or family history of atopy, dry skin, and visible eczema 2, 3, 4
The American Journal of Clinical Dermatology recommends that the sign of Darier (urtication on rubbing, positive in 89-94% of mastocytoses) should be assessed 1, 5

The American Journal of Clinical Dermatology describes three main forms of cutaneous mastocytosis in children: urticaria pigmentosa (65%), mastocytomas (10-35%), and diffuse cutaneous mastocytosis (1-3%) 1, 5
The American Journal of Clinical Dermatology suggests that investigations for mastocytosis should include physical examination with the sign of Darier, serum tryptase, complete blood count, and skin biopsy with immunostaining for tryptase and KIT 1

The British Medical Journal recommends that the presence of secondary infection signs (crusts, discharge, erosions) should be identified 2, 6
The Praxis Medical Insights suggests that acyclovir is indicated for eczema herpeticum, and empirical antibiotics (cephalexin or flucloxacillin) may be added to cover secondary bacterial infection 6

The British Medical Journal warns against missing a herpetic infection, which requires a Tzanck smear and urgent antiviral treatment 2, 6
The American Journal of Clinical Dermatology advises against underestimating neonatal pustules, which always require investigation to exclude infectious disease 1
The American Journal of Clinical Dermatology recommends recognizing the deterioration of eczema, which suggests secondary infection requiring bacterial and viral cultures 2, 4