Endocrine Abstracts

Background: Hypophosphatemia is of relevant clinical importance, especially in its severe form. Hypophosphatemia occurs when serum phosphate levels are below 0.84 mmol/l. It can be divided into a mild form (serum phosphate between 0.5 and 0.83 mmol/l), a moderate form (serum phosphate between 0.3 and 0.5 mmol/l) and a severe form (serum phosphate <0.3 mmol/l). Approximately 2.2 to 3.1% of hospitalized patients not requiring intensive care are affected (Brunelli et al., 2007). There are multiple causes such as chronic alcohol consumption, parenteral nutrition or sepsis. However, it has been observed that a mostly mild form of hypophosphatemia often occurs in routine laboratory controls. Aim of the study was to assess the frequency of subtypes of hypophosphatemia and to identify their causes.

Methods: In a retrospective analysis between March 2014 and March 2016, laboratory values from a total of n=34103 patients were collected and statistically evaluated. The parameters tested were phosphate, calcium, alkaline phosphatase, creatinine and albumin.

Results: A very high prevalence of hypophosphatemia (23.9%) was demonstrated. The mild form is by far the most common, while the severe form is, as expected, rare. In numbers: the mild form of hypophosphatemia occured in 21.3% (n=7920) of all patients, the moderate form in 2.1% (n=705) and the severe form in 0.5% (n=165) of patients. The further results were obtained using correlation matrixes. According to initial findings, hypophosphatemia may not occur when creatinine levels are elevated. In the severe form hypophosphatemia can be associated with hypocalcemia.