Delay in Diagnosis of Diabetes Mellitus Due to Inaccurate Use of Hemoglobin A1C Levels

Article Figures & Data

Table 1.

Diabetes Mellitus Diagnostic Criteria⁵

Fasting plasma glucose of ≥126 mg/dL

Classic symptoms of diabetes (polyuria, polydipsia, and weight loss) plus random plasma glucose of ≥200 mg/dL

Two-hour plasma glucose of ≥200 mg/dL during an oral glucose tolerance test using WHO parameters, using a 75-g glucose load

Table 2.

Historical Values from Laboratory Examinations for Mrs. J

Date	Fasting Plasma Glucose (mg/dL)	Hemoglobin A_1C	Hemoglobin (g/dL)	Hematocrit
Feb 1999	119	0.45
Aug 1999	82	0.38	9.6	0.275
Dec 2000		0.41	12.4	0.351
Apr 2001	137	0.41	11.8	0.343
Mar 2002	136	0.46	10.9	0.296
Apr 2003	192	0.50	10.3	0.296
Apr 2004	170	0.44	11.4	0.330
Mar 2005	187	0.48	10.6	0.297