Table 5.
Conditions that can falsely increase or decrease HgbA1c values
| Falsely low HgbA1c | Falsely high HgbA1c |
|---|---|
| 1. Hemoglobinopathies | 1. Hemoglobinopathies |
| Hgb S | fetal hemoglobin |
| Hgb D | Hgb Stanleyville II |
| Hgb GRAZ | Hgb OSU-Christiansborg |
| Hgb TAKAMATSU | Hgb Raleigh |
| Hgb G-SZUHU | Hgb D |
| Hgb ETOBICOKE | Hgb K-Woolwich |
| Hgb O Padova | 2. Carbamylated hemoglobin |
| methemoglobinemia | 3. Anemia |
| 2. Hemolysis | Iron deficiency |
| 3. Medications | Vitamin B12 deficiency |
| Dapsone | Folate deficiency |
| Methylene blue | |
| Phenacetin | |
| Benzene derivatives | |
| Vitamin C excess | |
| 4. Chronic lymphocytic leukemia | |
| 5. Nitrates | |
| 6. Hereditary spherocytosis | |
| 7. Hemodialysis | |
| 8. Venesection | |
| 9. Post blood transfusion |
Hgb indicates hemoglobin.