When the serum vitamin B12 level is borderline low, an elevated methylmalonic acid (MMA) level can be used to confirm a vitamin B12 deficiency.
Metformin may lead to a vitamin B12 level.
Tag: lab test
Diabetes type 1 – diagnosis
Positive Anti GAD and Low C peptide at the time of diagnosis is consistent with type 1 DM.
False negative or normal BNP
- Obesity
- Heart failure meds
- Pure right heart failure
D dimer
A negative D-dimer assay has a high negative predictive value for DVT, so the diagnosis can be ruled out in a patient who has a low pretest probability and a negative D-dimer result.
A negative D-dimer assay does not rule out DVT in a patient with a moderate to high pretest probability (SOR C).