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| A B C D E F G H I J K L M N O P Q R S T U V W X Y Z # |
Albumin, Random Urine with creatinine
Test CodeCPT Codes
82043, 82570
Preferred Specimen
Minimum Volume
Other Acceptable Specimens
Instructions
Note: Exercise within 24 hours, infection, fever, congestive heart failure, marked hyperglycemia, and marked hypertension may elevate urinary albumin excretion over baseline values.
Transport Temperature
Specimen Stability
Refrigerated: 7 days
Frozen: 28 days
Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Methodology
Turbidimetric
Setup Schedule
Reference Range
| Albumin, Urine | Not established |
| Albumin/Creat Ratio, Random Urine | <30 mcg/mg creat |
Creatinine, Random Urine
| ≤6 Months | 2-28 mg/dL | |
| 7-11 Months | 2-31 mg/dL | |
| 1-2 Years | 2-110 mg/dL | |
| 3-8 Years | 2-130 mg/dL | |
| 9-12 Years | 2-160 mg/dL | |
| >12 Years Male | 20-320 mg/dL | |
| >12 Years Female | 20-275 mg/dL | |
Clinical Significance
This test is used to detect albuminuria by measuring albumin and creatine concentrations in a random (spot) urine sample and calculating the albumin-creatinine ratio (ACR). This test is useful for assessing kidney damage, especially at an early stage, and informing management and prognosis of chronic kidney disease (CKD) [1].
Albuminuria, as a marker of kidney damage, provides a more specific and sensitive measurement of glomerular permeability than does proteinuria. An ACR measured from a spot urine sample acquired in the early morning is preferred for initial evaluation of albuminuria. This test can also be used to confirm a positive reagent strip urinalysis result. A moderately increased ACR (≥30 mg/g) for more than 3 months is diagnostic of CKD. The severity of albuminuria is also used for staging and prognosis of CKD [1,2].
Albuminuria generally appears before the reduction of glomerular filtration rate in people with diabetic glomerulosclerosis but may appear later in people with hypertensive nephrosclerosis. Albuminuria is independently associated with an increased risk of cardiovascular events and mortality. In individuals with diabetes and/or hypertension, early identification of albuminuria that prompts blood pressure and glycemic control may subsequently reduce the risk of cardiovascular events and CKD progressing to end-stage renal disease. Referral to specialist kidney care services is recommended in individuals with a consistent finding of severely increased ACR (≥300 mg/g) [1-4].
Factors that affect urinary ACR include menstrual blood contamination, symptomatic urinary tract infections, exercise, upright posture (orthostatic proteinuria), and other conditions that increase vascular permeability (eg, septicemia). Given the pathological and physiological causes of transient albuminuria, repeating ACR tests twice with early morning urine samples in the next 2 months is recommended. ACR from a timed urine sample can provide a more accurate estimate of albuminuria [1].
The results of this test should be interpreted in the context of pertinent clinical and family history and physical examination findings.
References
1. Kidney Disease: Improving Global Outcomes (KDIGO) CKD Work Group. KDIGO 2012 clinical practice guideline for the evaluation and management of chronic kidney disease. Kidney Int Suppl. 2013;3(1):1-150.
2. Inker LA, et al. Am J Kidney Dis. 2014;63(5):713-735.
3. American Diabetes Association. Standards of medical care in diabetes-2020. Diabetes Care. 2020;43(suppl 1):S135-S151.
4. Shin JI, et al. Hypertension. 2021;78(4):1042-1052.
