Metabolic alkalosis with hypoelectrolytemia in infants with cystic fibrosis

BACKGROUND: Infants with cystic fibrosis (CF) can develop episodes of hyponatremic hypochloremic dehydration with metabolic alkalosis when they sweat excessively, which is not caused by sweating in normal infants. We investigated the incidence of the metabolic alkalosis with hypoelectrolytemia in CF infants, the possible risk factors for its occurrence and the importance of the manifestation in the diagnosis of CF. METHODS: In order to evaluate the incidence and the risk factors for the development of this sweat-related metabolic disorder in CF, we reviewed the records of all children diagnosed as having CF before the age of 12 months in a 10-year period. Data analysis included medical history data, clinical features, biochemical parameters (blood pH, serum bicarbonate, sodium, chloride and potassium levels), sweat chloride test values, as well as genetic analysis data. RESULTS: The prevalence of metabolic alkalosis in association with low serum electrolyte concentrations (hyponatremia, hypochloremia, and hypokalemia) in infant CF population in our region was 16.5%. We found no season predilection in its occurrence. Early infant age, breast-feeding, delayed CF diagnosis, heat exhaustion and the presence of severe CF transmembrane conductance regulator mutations are predisposed factors for the development of metabolic alkalosis with hypoelectrolytemia. CONCLUSIONS: The results from our study suggest that metabolic alkalosis with hypoelectrolytemia is a relatively common manifestation of CF in infancy. The possibility of CF should be seriously considered in any infant with this metabolic disorder.     

Protein–energy malnutrition as the first manifestation of cystic fibrosis in infancy

Background:  The protein–energy malnutrition (PEM) that is characterized by hypoproteinemia, edema, and anemia has been reported in 5–13% of infants with cystic fibrosis (CF). Due to the surprising higher incidence of PEM as the first presenting manifestation of CF in Macedonia, the aim of the present study was to evaluate the possible risk factors in its development.
Methods:  Clinical and laboratory profiles (hemoglobin, red blood cell count, total serum protein, serum albumin and liver enzyme levels) and genotype data were analyzed in 115 newly diagnosed infants with CF, during the period 1990–2006.
Results:  PEM manifested in 39 CF infants (33%), usually within the first 5 months of life and in breast-fed infants. Mean hemoglobin, red blood cell count, total serum protein and serum albumin values in the PEM subgroup were, respectively, 76.0 g/L, 2.4 × 10¹²/L, 38.0 g/L and 16.6 g/L. Clinically significant liver involvement was found in 22 patients (56.4%) with PEM. Concerning the molecular basis of CF in these patients, PEM was always associated with ▵F508 , G542X , N1303K and other severe mutations.
Conclusion:  PEM is a common manifestation of CF in infancy. Early infant age, breast-feeding, impaired liver function and the presence of severe cystic fibrosis transmembrane conductance regulator mutations are predisposing factors for the development of PEM.