Determining Serum Zinc and Magnesium Levels in Hemodialysis Patients Could be Helpful for Clinicians.

Trace element determination is requested rarely for critically ill patients in Iran, due to the underestimation of the trace element determination by Iranian physicians. The aim was to compare the levels of Zn and Mg in a group of hemodialysis patients and normal individuals. This study shows that trace element determination is helpful for management of hemodialysis patients. Fifty-three hemodialysis patients and 51 control individuals were randomly analyzed for Zn and Mg serum levels. Comparison of before or after dialysis and with normal individuals was done and receiver operating characteristics (ROC) curves were plotted to evaluate the analytical sensitivity and specificity of Zn and Mg determination. Confidence interval for all statistical methods was 95 %. Zinc serum levels were decreased after hemodialysis insignificantly ( P  = 0.201) but Mg levels were decreased significantly ( P  = 0.000). Both Zn and Mg levels, before and after hemodialysis were meaningfully lower than normal controls ( P  < 0.05). ROC analysis showed that the area under the curve was high for Zn levels both before and after hemodialysis but it was high for Mg only before hemodialysis. Current study shows that serum Zn and Mg measurements can have clinical importance. Both before and after hemodialysis, serum Zn = 297.5 µg/L and Mg = 2.295 µg/L are proposed as cut-off values with about 90 % specificity, for monitoring of these two element in hemodialysis patients. It is suggested that clinicians consider the measurement of these trace elements for hemodialysis patients routinely or periodically as clinical chemistry tests.