Contributed by Lananh Nguyen, MD and Jeffrey Kant, MD, PhD
CLINICAL QUESTION
What benefit is there to perform additional MTHFR 1298A>C variant analysis as requested by clinician?
CHIEF COMPLAINT
A 61 year old female with a recent venous thrombosis and a wild-type MTHFR 677 genotype.
PAST MEDICAL HISTORY
Chronic lymphoblastic leukemia/Small lymphocytic lymphoma; Coronary artery disease, status post coronary artery bypass grafting; Carotid stenosis, status post endarterectomy; Neurogenic bladder, status post surgery; Cervical spondylosis, status post anterior cervical diskectomy and fusion; Malignant melanoma, status post excision, remote; Depression; Gastroesophageal reflux.
Social history: Tobacco
Family history: Coronary artery disease; Hypertension; Negative for clotting disorders; Negative for pregnancy loss.
Labs: No homocysteine, folate, or magnesium levels recorded. No reports of any genetic test results, such as Factor V Leiden or prothrombin, except MTHFR 677. Mutation analysis for MTHFR (677C>T) is NOT detected. Note: Laboratory has policy to send out for 1298A>C analysis only when 677T>C result is heterozygous.