[Acute phase response and serum magnesium levels among hospitalized patients]

The acute phase response (APR) is characterized by proteolysis with decreased body cell mass, hyperglycemia, body water retention and renal dysfunction, which we hypothesised could affect magnesium serum levels. The aim of this study was to compare serum magnesium levels among hospitalized patients with or without APR.

All serum magnesium results (n = 527) corresponding to a six-months period were searched at University Hospital mainframe. Relevant laboratorial and clinical details were also registered. All cases of diabetes mellitus, chronic renal insufficiency, or serum creatinine > 1.5 mg/dl were excluded. APR was defined by the presence of fever plus severe trauma or infection plus leukopenia or leukocytosis.

From a total of 214 patients, sixty-nine (32.2%) met the criteria for APR positivity (APR [symbol: see text]). Groups were paired for age, color, gender, diuretic use and edema presence. Hypomagnesemia was registered among 72% of cases, without statistical difference (p = 0.06) among APR [symbol: see text] and APR theta patients (63.8 vs 75.9%). Serum magnesium levels (median; range) were higher among APR [symbol: see text] cases, when compared to APR theta ones: 1.75; 1-3 vs 1.6; 0.9-2.9 m/dl, the same occurring with glycemia (115; 49-236 vs 99; 61-191 mg/dl) and serum creatinine (mean +/- SD): 0.8840 +/- 306 vs 0.803 +/- 0.257 mg/dl. Hypermagnesemia was more common among APR [symbol: see text] cases: 8.7 vs 2.1%.

Our results suggest that higher magnesium serum levels seen in APR [symbol: see text] patients may be attributed to subclinical renal ischemia and possibly to increased glucose serum levels.