Protein Creatinine Ratio (Urine) Test

Plasma proteins are essential for the survival of all living things. The kidneys, which are two organs located near the lower back, filter the blood, remove waste products and expel them from the body through urine. When the kidneys are functioning well, the proteins after filtration are reabsorbed and returned to the bloodstream.

Creatinine is a result of muscle metabolism that forms at a steady rate in the urine. The protein creatinine ratio is obtained after doing both a urine creatinine and a random urine protein test. The results come accurate after the 24-hour urine protein test.

A random urine protein creatinine ratio is sometimes replaced with a 24-hour urine protein sample. Preserving all of the urine for 24 hours is challenging for adults and impossible for infants and children.

If the kidneys are damaged or impaired due to other factors, they lose their ability to filter. Damaged kidneys allow detectable amounts of protein to leak into the urine. The presence of albumin in the urine can be detected using a dipstick test.

Urine protein creatinine ratio test measures protein and creatinine levels in the urine sample. Normal protein excretion in the urine is less than 150 mg per day, while albumin excretion is less than 30 mg per day. This test estimates the amount of protein you excrete in your urine per day and does not require collecting a 24-hour sample of your urine for testing.

Infections, stress, pregnancy, nutrition, cold exposure and intense exercise can cause temporary elevations in levels. Protein and creatinine in the urine for an extended time may indicate renal damage. Abnormal protein creatinine ratio in the urine due to underlying condition requires more testing to discover the cause.

Urine protein tests come in a variety of forms, including:

• As part of a urinalysis, a semi-quantitative protein dipstick can be conducted on a random urine sample.
• A 24-hour urine sample's protein content is tested and reported for the amount of protein released per 24 hours.
• The amount of protein and creatinine in a random urine sample as the urine protein to creatinine ratio (UPCR).

The liver produces a protein called albumin. This protein accounts for around 50% to 60% of the protein in the blood. Albumin is a critical component in detecting a probable kidney illness. The amount of albumin in the urine increases as kidney damage develops.

Proteinuria or protein in the urine is a common symptom of chronic conditions like diabetes and hypertension.

Increasing levels of protein in the urine indicate worsening kidney impairment. When it comes to early kidney injury, there are generally no indications or symptoms. Fluid build-up (oedema), shortness of breath, nausea and exhaustion may develop as kidney failure continues and protein loss is significant. Proteinuria can also be due to excessive protein synthesis, as observed in multiple myeloma, lymphoma and amyloidosis.

In persons with diabetes or hypertension, the albumin in the urine (albuminuria) is a sensitive sign of kidney damage. Patients with these diseases should get urine checked for protein creatinine ratio rather than total urine protein regularly, especially in a country like India. In India, three in every ten people have hypertension. Further, hypertension is responsible for nearly 17.5% of all deaths in India.

A urine sample is taken for the protein creatinine ratio. The doctor may ask to collect an early morning or collect 24-hour urine sample. In some cases, the physician might ask to collect midstream urine samples for appropriate evaluation.

Kidney disease, Acute renal failure, Preeclampsia, Nephrotic syndrome, Nephritic syndrome

The protein creatinine ratio reports reveal the normal or abnormal values of protein and creatinine present in the urine sample.

Protein creatinine ratio tests are advised by the doctor as:

• As part of a standard examination of kidney function.
• As a follow-up to a previous positive protein creatinine ratio.
• When it is essential to monitor kidney damage in a patient with renal disease.
• To see if a kidney function is improving as a result of the recommended treatment.

The doctor recommends the protein creatinine chart in the following conditions:

• In those with uncontrolled sugar levels in diabetes mellitus.
• In those with uncontrolled hypertension.
• In those with symptoms of acute kidney damage.
• In heart diseases like ischaemic heart disease, chronic heart failure, peripheral vascular disease or cerebrovascular disease.
• In those with structural renal tract disorders like recurrent renal stones.
• In those with symptoms of prostate hypertrophy.
• In those with the multisystem disorder with renal involvement, like systemic lupus erythematosus.
• In those with a family history of renal disorders or hereditary kidney diseases.
• In those with haematuria.
• In monitoring people on certain drugs like penicillamine.

The frequency of repeating your protein creatinine ratio reports depends upon the doctor's advice and the state of the disease.

• If the protein creatinine ratio reports are within the normal range, the test is repeated annually in those with kidney disease.
• The protein to creatinine ratio needs repetition every three months in people with acute renal injury. The repetition helps to ensure the healing process. The protein creatinine ratio results help the doctor to understand whether kidneys are functioning well.
• Similarly, the protein creatinine ratio chart needs repetition frequently in those with risk of kidney damage to assess the prognosis of the disease.

Before the Test

The Protein Creatinine Ratio urine test doesn't generally require fasting. But if specific instructions given by your healthcare provider regarding food, drink, or medication restrictions pertaining to another blood test scheduled for the same time, kindly follow them. Before the test, you will be provided with a sample collection kit. Usually the first urine of the morning is collected as a sample. If the test doesn't require morning urine, you should drink water for a few hours before the test.

During the test

If you are doing the sample collection at home, here are the steps generally involved:

• Clean your genital area thoroughly before the test to avoid contamination of the sample.
• Wash your hands and unseal the collection kit.
• Start urinating, and once you are midstream,  collect the urine in the container. Avoiding the initial and final parts of the stream are advisable.
• Securely cap the container without touching the inside.
• Wash your hands again.
• Label the collection jar with your details if not pre-labeled.

After the Test

• Store the collection jar with the sample in a cool and dry place away from sunlight which can degrade the sample.
• Hand the sample over to the healthcare professional sent by your online test provider.

The protein creatinine ratio values give an idea about proteins and creatinine eliminated through urine. These are the two parameters included in the protein creatinine ratio chart.

The urine creatinine ratio includes:

• Normal or elevated levels of protein in the urine sample.
• Normal or increased levels of creatinine in the urine sample.

The normal range of protein creatinine may differ slightly between laboratories. Some lab tests use different measurements. Discuss the significance of the test result with the doctor.

The protein creatinine ratio reports can get altered by muscle mass, animal protein intake, increased activity or the use of certain drugs.

The normal values and reference ranges of the test may vary from lab to lab. Please refer to the ranges mentioned in the report and consult a doctor to understand the interpretation of lab reports.

Protein creatinine ratio values slightly differ in various laboratories and based on methods used for testing.

• Protein creatinine ratio in the normal range indicates a person is healthy and kidney functions are normal.
• Increased levels of protein creatinine ratio mean excess of protein and creatinine leaking in the urine.

High protein creatinine values could be due to:

• Urinary tract infection
• Lupus
• Preeclampsia in pregnant women
• Hypertension
• Multiple myeloma
• Amyloidosis
• Bladder cancer
• Congestive heart failure
• Diabetes
• Therapies toxic to kidneys
• Heavy metal syndrome
• Goodpasture syndrome
• Myeloma
• Lymphoma
• Amyloidosis

Increased levels of protein creatinine ratio mean either the person is:

• On dialysis

People with kidney failure need regular dialysis. Dialysis functions like an artificial kidney and purifies the blood. In those with dialysis due to kidney damage, the protein creatinine ratio in urine samples might increase. Consulting the doctor to plan a diet and treatment could help in minimising protein creatinine ratio values.

• Needs dialysis

An increase in protein creatinine ratio values might be due to underlying kidney diseases. Which means the kidneys are not functioning well. In conditions with severe elevation in protein creatinine ratio values, the doctor might suggest undergoing dialysis.