Hypomagnesaemia in cystic fibrosis patients referred for lung transplant assessment

Abstract

Background Hypomagnesaemia in patients with cystic fibrosis (CF) is underrecognized although the true incidence is unknown. Many patients are asymptomatic, although severe deficiency may be associated with muscle weakness, cramps and tetany. Hypomagnesaemia may be a risk factor for post-transplant complications including convulsions, which may be exacerbated by the use of calcineurin inhibitors. The aims of the present study were to describe serum magnesium levels and to investigate the relationship between magnesium levels and age, and renal function measurements in patients with CF referred to a transplant centre for lung transplant assessment. Methods We reviewed the data of all 106 CF patients referred for transplant assessment from January 1995 to December 2003. Demographic and biochemical data were recorded and the explanatory variables were subjected to univariate analysis and linear regression analysis. Results Mean serum magnesium level was 0.75 mmol/L (range 0.46–1.03, normal range 0.74–1.1). 57% of patients had hypomagnesaemia. Serum magnesium levels were not associated with age, serum creatinine or GFR. Conclusions Hypomagnesaemia is a common finding in patients with CF referred for lung transplant assessment. Serum magnesium levels should be monitored in all CF patients being referred for lung transplant irrespective of the results of other renal function tests.