Il laboratorio nello screening del diabete gestazionale
Laboratory screening of gestational diabetes
AUTORI
1Medicina di laboratorio, AULSS 8 Berica, Vicenza
2Laboratorio di Patologia Clinica, A.S.S.T Valcamonica
ABSTRACT
Laboratory screening of gestational diabetes
Gestational diabetes mellitus (GDM) is defined by glucose intolerance first documented during pregnancy. The oral glucose tolerance test (OGTT) is currently the gold standard for the diagnosis of gestational diabetes mellitus, but many variables can affect its reproducibility and accuracy. An important source of pre-analytical variation affecting the glucose values is the type of tube employed for blood collection. Experts recommend immediately separation of the plasma from the cells by centrifugation, or to place the sample tube in an ice-water slurry and separate the plasma from the cells within 30 minutes from blood drawing. Being this approach impractical in daily practice, the use of a blood collection tube containing effective glycolysis inhibitors is a good alternative to avoid the decrease of plasma glucose concentration after blood drawing. Considering that the GDM diagnosis is based on cut off values, the use of tubes for blood collection that limit the in vitro glycolysis, could lead to an increase of the GDM prevalence. The impact of the increase is potentially of clinical significance: it is therefore fundamental that clinicians are aware of the main causes of preanalytical variability and how these variables can affect the patients’ outcome. A strict collaboration between the clinical laboratories and clinicians should therefore be started and maintained.
