Oxalate serum test

 An oxalate serum test is primarily ordered in the following conditions:

• When primary hyperoxaluria (high oxalates levels in urine) is suspected to be the cause of chronic kidney disease. 
• Absence of oxalates in urine - this usually occurs due to impaired kidney function in the later stage
• To check for the efficiency of dialysis in renal failure and hyperoxaluria patients 
• For maintaining blood oxalate levels below supersaturation, i.e., 25-30 mcmol/L (micromoles per litre).

Your healthcare practitioner may request this test if he/she observes signs and symptoms of a kidney stone such as: 

• Cloudy or foul-smelling urine
• Pain on urination
• Pink, red or brown urine
• Frequent urination
• Fever and chills, in case of urinary infection
• Urinating in small quantities
• Severe pain in the lower back, sides and below the ribs
• Pain radiating to the lower abdomen and groin
• Nausea and vomiting

This test also helps doctors to check the effectiveness of a low oxalate diet.

Fasting for at least 12 hours is necessary before this test. Inform your healthcare practitioner if you are taking any prescribed, non-prescribed or illicit drugs. Also, let him/her know if you have an inflammatory bowel disorder or have undergone an intestinal or colon surgery. 

Avoid spinach, peanuts, tomatoes, chocolate and vitamin C rich foods before the test.

A blood sample is required for this test. Your healthcare practitioner or nurse will withdraw the required amount of blood from a vein in your arm and send it to the laboratory for testing.

This procedure takes only a few minutes. You may experience mild pain or bruising at the site of the injection, but these symptoms fade away soon. If the bruising or discomfort persists, please inform your doctor.

Normal results:

Normally, oxalate level in the serum is less than 1.6 mcmol/L. This indicates that an individual is at low risk of having a kidney stone.

Abnormal results:

Oxalate serum levels above 1.6 mcmol/L are considered to be abnormal. This generally indicates that a person is at a high risk of developing a kidney stone. Other conditions which can cause abnormal oxalate levels are:

• Acute ethylene glycol poisoning 
• Mild metabolic hyperoxaluria: This can be due to high dietary intake of oxalate or vitamin C
• Enteric hyperoxaluria: Enteric hyperoxaluria is a condition in which a person has high oxalate levels in urine with very low urinary calcium. It can be due to inflammatory bowel disease, bowel resection, jejunoileal bypass or malabsorption
• Primary hyperoxaluria: This is a rare inherited disorder which causes overproduction of oxalate in the body.

Disclaimer: All results must be clinically correlated with the patient’s complaints to make a complete and accurate diagnosis. The above information is provided from a purely educational point of view and is in no way a substitute for medical advice by a qualified doctor.