Controversies on how diabetes is diagnosed.
OBJECTIVE
To evaluate the controversial aspects of diabetes diagnosis.


RESULTS
Within the past 2 years, revised guidelines for the diagnosis of diabetes have been issued which endorse the use of the hemoglobin A1C as a diagnostic test, in addition to the previously recommended tests. Updated diagnostic criteria for gestational diabetes were also published in the same period. Recent publications on the current role of oral glucose tolerance tests and diagnosis of diabetes in the acutely ill are sparse. There are new recommendations regarding the use of genetic testing and antibody testing in establishing the cause of diabetes.


CONCLUSIONS
The inclusion of A1C as a diagnostic test has many advantages including reproducibility of the test and convenience, but there are situations where the test is unreliable and it misses many individuals who would have been diagnosed by plasma glucose testing. The diagnostic threshold of 6.5% for the A1C remains controversial. There is still no consensus on the best approach to diagnose gestational diabetes. The role of the oral glucose tolerance test seems to be diminishing. Diagnosis of diabetes in acute illness is aided by A1C testing. Genetic and autoantibody testing in specific situations offer diagnostic and therapeutic utility.
University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA. samir.malkani@umassmemorial.org
Samir
S
Malkani
Taniya
T
DeSilva
D001786:Blood Glucose / Q000378:metabolism*; D003920:Diabetes Mellitus / Q000097:blood* / Q000175:diagnosis* / Q000453:epidemiology; D016640:Diabetes, Gestational / Q000097:blood / Q000175:diagnosis; D005260:Female; D005820:Genetic Testing; D005951:Glucose Tolerance Test; D006442:Glycated Hemoglobin / Q000378:metabolism*; D017408:Guidelines as Topic; D006801:Humans; D008297:Male; D011236:Prediabetic State / Q000097:blood / Q000175:diagnosis* / Q000453:epidemiology; D011247:Pregnancy; D015203:Reproducibility of Results
D001786:Blood Glucose; D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human