[Trends in parathyroid hormone plasma concentration in critically ill patients: prospective observational study].

OBJECTIVE: Introduction: There is no data in the literature regarding trends in parathormone serum concentration assessment in critically ill patients. The aim: To assess the parathyroid hormone plasma concentrations and kinetics in critically ill patients admitted to the intensive care unit due to multiorgan failure. PATIENTS AND METHODS: Materials and methods: Thirty multiorgan failure (at least circulatory and respiratory failure) patients were included. Patients who met any of the following criteria were excluded: acute liver failure, end stage renal disease, hypercalcemia, parathyroid gland disease, severe vitamin D deficiency, admission from another ICU or readmission, age younger than 18 years, or lack of consent from relatives. We performed the parathyroid hormone plasma measurements in 12-hour time intervals. RESULTS: Results: The initial parathyroid hormone plasma concentration levels in the study group were rather variable and medians exceeded laboratory reference values. Especially in the acute kidney injury subpopulation treated with continuous renal replacement therapy these trends were emphasized. The initial parathyroid hormone plasma concentration levels in this group significantly exceeded laboratory reference values in 80% of patients. After initial spike we observed subsequent drop between second and third measurement. The distribution of plasma levels was rather variable between second and third measurement in this group of patients. CONCLUSION: Conclusions: The parathyroid hormone plasma concentration levels in the critically ill patients are variable. In the acute kidney injury subpopulation treated with continuous renal replacement therapy after initial significant spike we observed subsequent drop between second and third measurement.

Vitamin D kinetics in the acute phase of critical illness: A prospective observational study.

PURPOSE: The objective of this study was to assess the vitamin D kinetics in critically ill patients by performing periodic serum vitamin D measurements in short time intervals in the initial phase of a critical illness. MATERIALS AND METHODS: We performed vitamin D serum measurements: at admission and then in 12-hour time intervals. The minimum number of vitamin D measurements was 4, and the maximum was 8 per patient. RESULTS: A total of 363 patients were evaluated for participation, and 20 met the inclusion criteria. All patients had an initial serum vitamin D level between 10.6 and 39ng/mL. Nineteen patients had vitamin D levels between 10 and 30ng/mL, which means that they had vitamin D insufficiency or deficiency, and only one patient had a normal vitamin D serum plasma level. We observed that the median of the vitamin D level decreases until the fourth measurement then stabilizes around the 4th and 5th measurement and then appears to increase unevenly. The highest drop is at the very beginning. CONCLUSIONS: The vitamin D serum level is changeable in the initial phase of a critical illness. We hypothesize that the serum vitamin D concentration can mirror the severity of illness.