Fructosamine

What is a Fructosamine Test?

A fructosamine test, also known as a serum fructosamine test, is a blood test that measures the fructosamine level in a person's bloodstream. Fructosamine is a compound formed when glucose (sugar) in the blood attaches to proteins, primarily albumin, and reflects a person's average blood sugar control over the past 2-3 weeks. This test is instrumental in monitoring and managing diabetes.

The fructosamine test is an alternative or complementary method to the more common hemoglobin A1c (HbA1c) test for assessing long-term blood sugar control. While HbA1c reflects blood sugar levels over 2-3 months, fructosamine offers a shorter-term view of blood glucose control. 

It is often used when immediate or frequent monitoring is necessary, such as during pregnancy, rapid changes in medication, or when there are concerns about recent blood sugar fluctuations.

To perform the fructosamine test, a blood sample is collected from a patient and sent to a laboratory for analysis. The results are reported in micromoles per liter (umol/L) and indicate the average blood sugar levels during the preceding weeks. High fructosamine levels suggest poor blood sugar control, whereas lower levels indicate better management.

This test is valuable for individuals with diabetes and their healthcare providers because it helps tailor treatment plans and medication adjustments, leading to more effective diabetes management. It can also be beneficial for pregnant women with gestational diabetes, people with type 1 diabetes, or those experiencing frequent blood sugar fluctuations. 

However, it's important to note that the fructosamine test is not a stand-alone diagnostic tool. It should be used with other tests and clinical evaluations to provide a comprehensive understanding of blood sugar control.

How Does it Work?

1. Sample Collection

A healthcare professional will collect a blood sample from the patient, typically by drawing blood from a vein in the arm. This sample should be collected in a special tube containing a glycolytic inhibitor to prevent the breakdown of glucose.

2. Laboratory Analysis

The blood sample is sent to a clinical laboratory for analysis.

In the lab, the serum or plasma is separated from the blood and mixed with a reagent containing nitroblue tetrazolium (NBT) and potassium hydroxide (KOH).

3. Formation of Fructosamine

The NBT/KOH reagent reacts with the fructosamine in the serum or plasma.

Fructosamine is a compound formed when glucose molecules attach to serum proteins, primarily albumin.

4. Color Development

As a result of the reaction, a color change occurs, typically from blue to brown.

5. Measurement of Absorbance

The color change is quantified by measuring the absorbance of light at a specific wavelength using a spectrophotometer.

6. Calculation of Fructosamine Level

The degree of color change is directly proportional to the concentration of fructosamine in the sample. The laboratory then calculates the fructosamine level in micromoles per liter (umol/L) based on the absorbance measurements.

7. Reporting Results

The results are reported to the healthcare provider, who can interpret the fructosamine level and use it to assess the patient's average blood sugar control over the previous 2-3 weeks.

The fructosamine test is a quantitative measure of glycemic control but is not a replacement for other diabetes monitoring tools, such as hemoglobin A1c (HbA1c) or daily glucose monitoring. It is often used with these tests to provide a comprehensive view of a patient's diabetes management.

Patients should consult with their healthcare provider to understand the significance of their fructosamine test results and make informed decisions regarding their diabetes treatment plan.

When Would You Use This Test?

The fructosamine test, or the serum fructosamine test, is a valuable tool for healthcare practitioners, particularly those involved in diabetes management, to assess and monitor a patient's blood sugar control. Here are key scenarios and situations in which this test is appropriately used:

Diabetes Management

Diabetes healthcare providers frequently use the fructosamine test to evaluate the effectiveness of a patient's diabetes treatment plan. It is beneficial when assessing short-term blood sugar control, making it a valuable complement to the hemoglobin A1c (HbA1c) test, which reflects long-term control.

Pregnancy and Gestational Diabetes

During pregnancy, monitoring blood sugar levels is crucial for the health of both the mother and the developing fetus. The fructosamine test is often used in conjunction with other glucose tests to assess glycemic control in pregnant women, including those with gestational diabetes.

Medication Adjustments

When a healthcare provider needs to make rapid medication adjustments, such as insulin dosing changes, the fructosamine test can provide a quick assessment of recent blood sugar control.

Frequent Blood Sugar Fluctuations

Patients experiencing frequent blood sugar fluctuations may benefit from this test as it offers a more immediate view of their glycemic control. It helps identify trends and patterns that might need to be evident in HbA1c results.

Patient Compliance and Lifestyle Changes

For patients who have recently made changes to their diabetes management plan, lifestyle, or medication regimen, the fructosamine test can help assess the impact of these changes quickly.

Individualized Patient Care

The fructosamine test is a valuable resource for tailoring diabetes management plans to individual patients, considering their specific needs and circumstances.

What do the Results Mean?

Fructosamine test results provide valuable insights into a patient's average blood sugar control over the previous 2-3 weeks, making them a crucial tool in diabetes management. 

The results are typically reported in micromoles per liter (umol/L) and can vary depending on several factors, including the individual's specific circumstances and treatment plan. Here's what common fructosamine test results typically mean:

Normal Range (Typically 200-285 umol/L)

Within this range, it suggests that the patient's blood sugar control over the past 2-3 weeks is well-maintained. It indicates that their diabetes management plan, including medication, diet, and lifestyle, effectively keeps blood sugar levels within target ranges.

High Fructosamine Levels (>285 umol/L)

Elevated fructosamine levels may indicate poor blood sugar control. This could result from missed doses of diabetes medications, inadequate diet management, insufficient physical activity, or illness.

Low Fructosamine Levels (<200 umol/L)

Very low fructosamine levels may suggest a risk of hypoglycemia or overly aggressive diabetes treatment. It could be indicative of frequent and severe episodes of low blood sugar, which may require treatment adjustments to prevent dangerous hypoglycemic episodes.

It's important to note that while the fructosamine test provides a valuable snapshot of short-term blood sugar control, it should not be the sole basis for medical decisions. Healthcare providers should consider fructosamine results in conjunction with other tests and clinical assessments, such as hemoglobin A1c (HbA1c) and daily glucose monitoring, to get a comprehensive view of a patient's diabetes management.

Fructosamine results require individualized interpretation based on age, health, and diabetes type. Healthcare providers should collaborate with patients to adjust medications and lifestyles for optimal blood sugar control.

Research & Evidence

The Fructosamine Test, also known as the serum fructosamine test, emerged in response to the limitations of the Hemoglobin A1c (HbA1c) test, which reflects blood sugar control over a 2-3 month period. Clinicians recognized the need for a test that could provide insights into shorter-term glycemic control.

In the early 1980s, researchers began investigating the measurement of fructosamine, a compound formed when glucose molecules attach to serum proteins, primarily albumin. This led to the development of a laboratory test to quantify fructosamine levels.

Clinical studies were conducted to assess the reliability and clinical significance of fructosamine measurements. These studies aimed to establish a correlation between fructosamine levels and shorter-term blood sugar control, typically over 2-3 weeks.

It provided evidence that the Fructosamine Test was a valuable resource for healthcare providers, particularly in scenarios requiring immediate or frequent monitoring of blood sugar control. It was especially useful during pregnancy when adjusting medications and for patients with fluctuating glucose levels.

Clinical guidelines and recommendations have been developed, advocating its use in specific clinical scenarios. It has become an integral part of diabetes care, helping healthcare providers tailor treatment plans and make medication adjustments based on recent glycemic control.

References

• HealthMatters.io LLC. (n.d.). Fructosamine | Healthmatters.io. https://healthmatters.io/understand-blood-test-results/fructosamine
• Novkovic, B. (2021, January 19). Fructosamine Test: High & Low Levels + Normal Range. SelfDecode Labs. https://labs.selfdecode.com/blog/fructosamine/
• Onlinects, & Onlinects. (2019, December 27). FRUCTOSAMINE TESTING ?? canine - Glencoe Animal Hospital. Glencoe Animal Hospital - Glencoe Animal Hospital. https://glencoeanimalhospital.com/fructosamine-testing-canine/
• Saroj, G., & Saroj, G. (2023, January 5). Fructosamine Test: Purpose, HbA1c Difference & Collection [2023]. Bookmerilab. https://bookmerilab.com/tests/blood-tests/fructosamine-test/
• Sobel, D. O., & Abbassi, V. (1991). Use of fructosamine test in diabetic children. Diabetes Care, 14(7), 578??583. https://doi.org/10.2337/diacare.14.7.578