Dermatitis as a presenting sign of cystic fibrosis

Three percent to 13% of patients with cystic fibrosis present with protein-energy malnutrition that is characterized by hypoproteinemia, edema, and anemia and is associated with high morbidity and mortality. Cutaneous manifestations of malnutrition are rare in patients with cystic fibrosis and have been attributed to deficiencies of protein, zinc, and essential fatty acids.

We describe five patients who presented with failure to thrive, hypoproteinemia, edema, and a cutaneous eruption before the onset of pulmonary symptoms and before the diagnosis of cystic fibrosis was made. The rash had a predilection for the extremities (lower > upper), perineum, and periorificial surfaces. In most cases, erythematous, scaling papules developed by 4 months of age and progressed within 1 to 3 months to extensive, desquamating plaques. Alopecia was variable, and mucous membrane or nail involvement was not observed. The rash was associated with malnutrition and resolved in all survivors within 10 days of providing pancreatic enzyme and nutritional supplementation. The pathogenesis of the rash is unclear, but it appears to stem from deficiencies of zinc, protein, and essential fatty acids and may be mediated by alterations in prostaglandin metabolism.

Cystic fibrosis should be included in the differential diagnosis of the red, scaly infant, particularly when failure to thrive, hypoproteinemia, and edema are also present. Recognition of rash as a sign of cystic fibrosis complicated by protein-energy malnutrition will allow earlier diagnosis and treatment of these patients and may improve their outcome.