DOES LITHIUM-CARBONATE AFFECT THE ION-TRANSPORT ABNORMALITY IN CYSTIC-FIBROSIS

Lithium is known to affect several aspects of cellular regulation which may be related to ion channel function in epithelial cells. To determine whether the ion transport abnormality in cystic fibrosis (CF) is affected by lithium with resultant changes in clinical status, 36 CF patients, 12–37 years old, were enrolled in a 14 week, double‐blind, placebo‐controlled trial. Eighteen patients were randomly assigned to receive lithium carbonate for 10 weeks. At the end of therapy their average serum lithium concentration was 0.56 ± 0.06 mmol (SEM) per liter. Their sweat chloride concentration fell from 92.1 ± 4.8 mmol per liter to 87.4 ± 4.0 mmol per liter after 10 weeks of therapy (P = 0.07) and rose to 94.4 ± 3.5 mmol per liter 4 weeks after end of therapy (P < 0.001 compared to results at end of therapy). Their forced vital capacity (FVC) fell from 72 ± 5.3% of predicted to 66 ± 5.1% of predicted after 4 weeks of therapy (P < 0.01), and their forced expiratory volume in one second (FEV1) fell from 56 ± 5.5% of predicted to 51 ± 5.5% of predicted after 4 weeks of therapy (P < 0.01). In a non‐blind assessment, performed 19 weeks after the end of therapy, their FVC and FEV1 had risen and were not significantly different from baseline. Sweat chloride, FVC, and FEV1 remained unchanged in the placebo group throughout the period of study. We conclude that in patients with CF lithium affects the function of the lungs and sweat glands, two organ systems in which the CF epithelial cell defect is well recognized. Several mechanisms could account for these lithium effects. Since pulmonary function deteriorated during short‐term lithium administration, lithium as used in this study has no therapeutic value in CF and pulmonary function must be closely monitored when lithium is used for manic‐depressive disease in patients with CF. Pediatr Pulmonol 1990; 8:82‐88. Copyright © 1990 Wiley‐Liss, Inc., A Wiley Company