Essential fatty acids in infantile seborrheic dermatitis.

BACKGROUND

In infantile seborrheic dermatitis (ISD) several different pathogenetic mechanisms have been proposed.

OBJECTIVE

The purpose of the study was to investigate the importance of essential fatty acids (EFAs) and their metabolites in the origin of ISD.

METHODS

The serum EFA patterns of 30 children with ISD, 1 to 6 months of age, were studied for 2 to 5 months. Blood samples were obtained at the time of diagnosis and after spontaneous recovery. Control samples were taken from age-matched healthy children.

RESULTS

In children with active dermatitis levels of EFA 18:1w9 were increased and levels of 18:2w6 were decreased, whereas 20:4w6 levels remained normal. The rare fatty acid 20:2w6 was found in significant amounts in 20 patients, but at only barely detectable levels in the controls. All deviant values but the levels of 20:2w6 were normal at the time of recovery. Breast milk samples were obtained at the time of diagnosis from the patients' mothers and from a control group consisting of healthy nursing mothers. The EFA patterns were identical. The differences in EFA pattern between children with ISD and those free of skin disease were significant. The normalization of the deviation in ISD paralleled the recovery at any age it occurred.

CONCLUSION

The laboratory findings suggest a transient impaired function of the enzyme delta-6-desaturase. The altered EFA pattern in ISD may be important in the pathogenesis of the disease.