Aminoglycosides lower serum magnesium concentrations in patients with cystic fibrosis: a retrospective study

Magnesium in cystic fibrosis--Systematic review of the literature

BACKGROUND

The metabolism of sodium, potassium, and chloride and the acid-base balance are sometimes altered in cystic fibrosis. Textbooks and reviews only marginally address the homeostasis of magnesium in cystic fibrosis.

METHODS

We performed a search of the Medical Subject Headings terms (cystic fibrosis OR mucoviscidosis) AND (magnesium OR hypomagnes[a]emia) in the US National Library of Medicine and Excerpta Medica databases.

RESULTS

We identified 25 reports dealing with magnesium and cystic fibrosis. The results of the review may be summarized as follows. First, hypomagnesemia affects more than half of the cystic fibrosis patients with advanced disease; second, magnesemia, which is normally age-independent, relevantly decreases with age in cystic fibrosis; third, aminoglycoside antimicrobials frequently induce both acute and chronic renal magnesium-wasting; fourth, sweat magnesium concentration was normal in cystic fibrosis patients; fifth, limited data suggest the existence of an impaired intestinal magnesium balance. Finally, stimulating observations suggest that magnesium supplements might achieve an improvement in respiratory muscle strength and mucolytic activity of both recombinant and endogenous deoxyribonuclease.

CONCLUSIONS

The first comprehensive review of the literature confirms that, despite being one of the most prevalent minerals in the body, the importance of magnesium in cystic fibrosis is largely overlooked. In these patients, hypomagnesemia should be sought once a year. Furthermore, the potential of supplementation with this cation deserves more attention.

Side effects of aminoglycosides on the kidney, ear and balance in cystic fibrosis

Aminoglycoside antibiotics are a central component of the treatment of pulmonary exacerbations of cystic fibrosis (CF) and slow the decline in lung function which ultimately causes the death of most patients. The prognosis of CF has improved, and thus side effects of treatments have become increasingly important. Observational studies suggest that the morbidity from side effects of aminoglycosides is disturbingly common, and that aggressive treatment may lead to more side effects. This review of the current literature on side effects of aminoglycosides considers the pathophysiological mechanisms, epidemiology and risk factors, investigation of side effects and preventative strategies. Treatments which have shown early promise are identified and areas of future research are discussed.