Methylmalonic Acid

Label Mnemonic:	MMAUR
Epic code:	LAB3601
Downtime form:	Doctor/Provider Orders - Pathology Core and Specialty Care Nursery

Commercial Mailout Laboratory
6240-8 RCP
356-8593

Specimen(s):

Urine (24 hr or random) More information

Specimen Instructions:

Refrigerate during collection in plastic container.

Collection Medium:

Urine - 24 hour/timed plastic urine container

Minimum:

Preferred Minimum:  4 mL urine from a well-mixed 24-hour or random
                    urine collection; refrigerated during collection/
                    submission to laboratory.

Rejection Criteria:

Room temperature specimens.

Delivery Instructions:

Submit refrigerated specimen to laboratory as soon as possible after collection period is completed.

Turn Around Time:

1-5 days upon receipt at reference laboratory.

Reference Range:

Components                    Reference Interval
Methylmalonic Acid, Urine    0.0-3.6 mmol/mol CRT

Creatinine (24-hour)        Male                        Female
                    3-8 yrs:  140-700  mg/d     3-8 yrs:  140-700  mg/d
                    9-12 yrs: 300-1300 mg/d     9-12 yrs: 300-1300 mg/d
                   13-17 yrs: 500-2300 mg/d    13-17 yrs: 400-1600 mg/d
                   18-50 yrs: 1000-2500mg/d    18-50 yrs: 700-1600 mg/d
                   51-80 yrs: 800-2100 mg/d    51-80 yrs: 500-1400 mg/d
                   81 yrs+:   600-2000 mg/d    81 yrs+:   400-1300 mg/d

Interpretive Data:

Elevated urinary methylmalonic acid is an early and sensitive indicator of vitamin B12 (cobalamin) deficiency. This test can also be used to monitor patients with methylmalonic aciduria. Diagnosis of methylmalonic aciduria requires an organic acid panel and appropriate clinical history.

Methodology:

Quantitative High Performance Liquid Chromatography-Tandem Mass Spectrometry

CPT Code:

83921

See Additional Information:
Urine Tests Requiring Preservatives, Refrigeration or Special Containers