Mechanisms and causes of hypomagnesemia.

PURPOSE OF REVIEW: Identification of the mechanisms of magnesium absorption and reabsorption has markedly enhanced our understanding of the causes of hypomagnesemia. RECENT FINDINGS: New gastrointestinal and renal causes of hypomagnesemia have been recently documented. SUMMARY: The recognition of new mechanisms and causes of magnesium absorption and reabsorption should enhance the ability to monitor patients at risk for hypomagnesemia and improve our ability to mitigate the serious symptoms associated with this disorder.

Commentary: CME and its role in the academic medical center: increasing integration, adding value.

Continuing medical education (CME), as it is currently structured, funded, and institutionalized, plays a marginal role in the academic medical center (AMC). In contrast, several models of more effective, integrated CME exist, and these enable the AMC to better achieve its potential in education, research, and health care delivery. Examples of such models are presented, emphasizing quality and performance improvement; regional, national, and public outreach; faculty and staff development; and research and scholarly activity. Although there are many reasons to maintain the status quo of CME programs, there are offsetting forces for change to be found in accreditation processes, movements toward maintenance of certification and licensure, and the need for the AMC to achieve higher quality standards. These models may offer a view of the potential of academic CME to be a major vehicle for the effective integration in quality, regional, and faculty development arenas, and as a scholarly and outcomes-oriented pursuit. Sitting at the right table and sufficiently integrated, CME holds real potential to help the AMC meet its multiple goals and missions.

Pseudohyperphosphatemia in a hyperphosphatemic hemodialysis patient.

Hyperphosphatemia is a predictable consequence of end-stage renal disease. Pseudohyperphosphatemia is a spurious elevation of serum phosphate in samples containing a substance that interferes with the laboratory assay for phosphate. The most common cause is a paraprotein in disorders such as Waldenström's macroglobulinemia and multiple myeloma. We report here a case of pseudohyperphosphatemia in a hyperphosphatemic patient with end-stage renal disease on long-term hemodialysis caused by a saline solution containing phosphorus used to dilute the patient's serum sample in the clinical chemistry laboratory. Investigations showed that the phosphorus most likely was introduced at the time of saline manufacture. Pseudohyperphosphatemia resulting from the manufacture and distribution of saline-containing phosphorus could be a cause of abnormally high serum phosphate measurements in hyperphosphatemic dialysis patients whose serum samples must be diluted in the laboratory. Such spuriously elevated results can lead to inappropriate changes in medications and subject patients to additional hemodialysis treatments.