Dermatitis as a presenting sign of cystic fibrosis.

BACKGROUND: 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. OBSERVATIONS: 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. CONCLUSIONS: 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.

Effect of pancreatic enzyme supplements on iron absorption.

Iron deficiency has been reported in one third of patients with cystic fibrosis. There are data that suggest that iron absorption is increased with exocrine pancreatic deficiency and that administration of pancreatic enzymes may impair oral iron absorption. We compared oral iron absorption over a 3-hour period in the presence and absence of exogenous pancreatic enzymes in 13 stable young-adult patients with cystic fibrosis and 9 age-matched control patients. Although none of the patients with cystic fibrosis had a hemoglobin level less than 119 g/L, serum ferritin levels were less than 25 micrograms/L in 5 of the 13 patients, and the mean corpuscular volume was significantly lower in the patient group (86.1 +/- 2.7 vs 90.9 +/- 5 fL). Baseline mean serum iron levels were higher in controls (18.9 +/- 5.9 mumol/L) than in patients (11.9 +/- 6.3 mumol/L). There was no difference in iron absorption in the absence of exogenous pancreatic enzymes. Significant impairment of iron absorption was detected in both patients with cystic fibrosis and controls after administration of a preparation of pancreatic enzymes. There was an inverse relationship between iron stores, as measured by serum ferritin, and iron absorption. These findings suggest that long-term consumption of pancreatic enzymes by patients with cystic fibrosis may contribute to iron deficiency.

Nifedipine inhibits hypoxic pulmonary vasoconstriction during rest and exercise in patients with cystic fibrosis and cor pulmonale.

Nifedipine has recently been reported to reduce pulmonary artery pressure and pulmonary vascular resistance during rest and exercise in adult patients with hypoxic pulmonary hypertension from chronic obstructive pulmonary disease. To determine whether nifedipine reduces pulmonary vascular resistance in patients with cor pulmonale from cystic fibrosis (CF), we studied 2 patients with severe CF lung disease during rest and exercise while breathing room air or receiving low-flow oxygen therapy. Nifedipine markedly lowered pulmonary vascular resistance and improved cardiac index and pulmonary pressure-flow relationships during all treatment conditions. Nifedipine did not substantially change arterial PO2, except for a slight decrease during exercise while receiving low-flow oxygen. Nifedipine, however, markedly increased oxygen delivery during rest and exercise. Both patients noted improved exercise tolerance with chronic nifedipine therapy. Nifedipine may be a useful adjuvant to supplemental oxygen in the treatment of patients with CF and cor pulmonale.