Objective: To determine the prevalence and most common etiologies of scalp scaling in infants and prepubertal children and the specificity of head and neck lymphadenopathy for the diagnosis of tinea capitis associated with scalp scaling.
Design/methods: A cross-sectional study of 300 children, 200 from an urban general pediatric practice and 100 from 2 urban pediatric dermatology practices, was conducted. Half of the subjects were <2 years old, and half were 2 to 10 years old. Demographic data, medical history, and clinical data noting the presence of scalp scaling and other scalp signs and symptoms, as well as adenopathy of the head and neck, were collected.
Results: Scalp scaling was seen in 66 (22%) children. There was an insignificantly higher prevalence of scalp scaling in those <2 years old compared with the 2- to 10-year-old group. In those <2 years old with scalp scaling, the most common diagnoses were seborrheic dermatitis (thick, adherent, greasy scale predominantly in the frontal and/or vertex areas of the scalp) and atopic dermatitis/eczema. Among those 2 to 10 years old with scalp scaling, the most common diagnoses were nonspecific (fine, white) scaling, seborrheic dermatitis, and atopic dermatitis/eczema. Nine (3%) patients were culture-positive for a dermatophyte, all of whom were black, and grew Trichophyton tonsurans. More than half (52.7%) of all patients had head and neck adenopathy. The presence of posterior nodes was significantly associated with atopic dermatitis/eczema and marginally associated with a positive dermatophyte culture. The presence of scalp scaling plus posterior adenopathy was significantly associated with seborrheic dermatitis and a positive dermatophyte culture in the entire study population and with atopic dermatitis in the pediatric dermatology clinics.
Conclusions: Scalp scaling was common in children 0 to 10 years old. Infantile-type seborrheic dermatitis was noted in both age groups: it was 3 times as likely in children <2 years old (18%) than in those 2 to 10 years old (6%). Contrary to traditional teaching, seborrheic dermatitis can be found in preadolescent children. Atopic dermatitis/eczema was associated with scalp scaling in both age groups. Head and neck adenopathy was very common and nonspecific for any 1 diagnosis. Posterior adenopathy with concurrent scalp scaling was significantly associated with seborrheic dermatitis, a positive dermatophyte culture, and atopic dermatitis. In this nonselected pediatric population, scalp scaling with adenopathy was not associated exclusively with tinea capitis.