HomeHealth articleskidney disordersWhat Is Renal Glycosuria?

Renal Glycosuria - Pathology, Types, Symptoms, Diagnosis, and Treatment

Verified dataVerified data
0

4 min read

Share

Renal glycosuria is a condition characterized by the excessive and abnormal excretion of sugar in the urine. To know more, read the following content.

Medically reviewed by

Dr. Manzoor Ahmad Parry

Published At November 23, 2022
Reviewed AtNovember 23, 2022

Introduction:

The term glycosuria indicates the presence of simple sugars such as glucose, fructose, galactose, lactose, etc., in the urine. Kidneys play an important role in filtering the blood through which the excess sugars, if present in the blood, will be eliminated through the urine. The renal tubules play an important role in reabsorbing the sugars as well as excreting them if they are in excess amounts. But in cases of diseases or disorders affecting the kidney, especially the tubules, it would affect normal functioning resulting in excessive excretion of sugar in the urine despite normal or low blood sugar levels. Renal glycosuria is one of the rare conditions.

What Is Renal Glycosuria?

Renal glycosuria is a rare condition that is characterized by the excessive excretion of sugar in the urine. Renal glycosuria can occur even though the blood glucose levels are normal or lower than the normal range.

What Are the Other Terminologies Used to Define Renal Glycosuria?

The other synonyms of renal glycosuria include:

  • Benign glycosuria.

  • Nondiabetic glycosuria.

  • Renal glucosuria.

  • Primary renal glycosuria.

  • Familial renal glycosuria.

What Is the Epidemiology of Renal Glycosuria?

It is estimated that it occurs in about 1 in 33,000 individuals among the general population. It does not show any gender discrimination affecting males and females equally. It is suggested to be more prevalent in conditions such as starvation and pregnancy. It can be inherited as both autosomal dominant and autosomal recessive inheritance patterns.

What Is the Difference Between Physiologic And Pathologic Glycosuria?

  • Physiologic Glycosuria: It is a transient condition that is characterized by the excretion of sugar in the urine that occurs when a person consumes an excessive amount of carbohydrates. The presence of a small amount of glucose up to 0. 25 mg/ml in the random fresh urine is considered normal as it can occur due to overconsumption of carbohydrates or other physiological conditions.

  • Pathologic Glycosuria: It is characterized by the excessive excretion of sugar in the urine due to improper kidney function or other mechanisms that are involved in normal glucose metabolism and excretion. The diagnosis of pathologic glycosuria is made when there is more than 0. 25 mg/ml of glucose in the random fresh urine.

What Is the Pathophysiology of Renal Glycosuria?

  • Kidneys play an important role in glucose reabsorption and excretion. The glomerulus filters the glucose present in the blood, which is then reabsorbed by the renal tubules. Usually, the renal tubules of the properly functioning kidneys would reabsorb almost all the glucose filtered by the glomeruli leaving less than 25 mg/dl of glucose in the urine. This capacity of the renal tubules to reabsorb the glucose filtered by the glomeruli and prevent its excretion in the urine is called the renal threshold.

  • When the amount of glucose filtered by the glomeruli exceeds the amount of glucose reabsorbed by the tubules, violating the renal threshold, the excessive unabsorbed glucose would be eliminated in the urine. This may occur due to two reasons, either due to the increased plasma sugar levels which occur in patients with diabetes mellitus or when the reabsorbing capacity of the renal tubules is affected due to any disease conditions affecting the kidneys.

What Is Transport Maximum for Glucose (TmG)?

TmG is the maximum capacity or point at which the increase in the concentration of glucose would not result in its excretion in the urine. If this capacity or point is crossed, the glucose will be excreted in the urine. In healthy adults and children, this value ranges from 260 to 350 mg/minute.

What Are the Types of Renal Glycosuria?

There are three subtypes of renal glycosuria; they are as follows:

  • Renal Glycosuria, Type A - Is characterized by a low renal threshold and reduced TmG.

  • Renal Glycosuria, Type B - Is characterized by a low renal threshold and normal TmG.

  • Renal Glycosuria, Type 0- Is characterized by the complete absence of renal tubular reabsorption.

What Is the Etiology of Renal Glycosuria?

The causes of renal glycosuria include:

  • Membrane Transport Disorders - These are usually inherited disorders affecting the transport of glucose across the cell membrane. These disorders commonly occur due to harmful genetic mutations affecting the membrane transport of glucose. In this condition, the body starts to recognize the low levels of glucose as normal and begins to excrete the glucose in the urine; hence the normal renal threshold is reduced to low levels.

  • SLC5A2 Gene Mutation - The renal sodium-glucose cotransporter gene is responsible for mediating the activity of sodium-glucose cotransporters SGLT1 and SGLT2. These are the membrane proteins that mediate the reabsorption of glucose from the proximal convoluted tubules of the kidney. Genetic mutations in the SLC5A2 gene would result in loss of function of the SGLT1 and SGLT2, resulting in impaired reabsorption of glucose by the renal tubules.

What Are the Signs And Symptoms of Renal Glycosuria?

The majority of cases of renal glycosuria do not produce any apparent symptoms; only a few cases present with symptoms, and they are as follows:

  • Polyuria (increased urine output).

  • Polydipsia (excessive thirst).

  • Enuresis (involuntary urination).

  • Mild delays in growth and development during puberty.

  • Dehydration (loss of excess body fluid).

How Is Renal Glycosuria Diagnosed?

  • History: A thorough history of the symptoms should be collected from the patient as it provides a major clue in the diagnosis of the condition.

  • Urinalysis:

    • Urine Sugar Estimation - This would indicate the presence of excessive sugar in the urine to values more than 25 mg/dl.

  • Blood Test:

    • Blood Sugar Levels - This would indicate normal or low blood sugar levels.

  • Genetic Testing:

    • SLC5A2 Genetic Studies - This would indicate the mutation in the SLC5A2 gene.

How Is Renal Glycosuria Treated?

  • There is no specific treatment for renal glycosuria as it does not produce any life-threatening issues.

  • The patients are advised to undergo routine urine tests to estimate their urine sugar levels and blood sugar levels.

  • The patients should be advised to check for diseases such as diabetes mellitus, which is one of the major reasons for glycosuria, and hypoglycemics should be prescribed to prevent further complications.

  • Genetic counseling - The affected person, as well as the family members, should be properly educated about the benign nature of the condition, and they should be reassured, as it would provide big mental support.

Conclusion:

Renal glycosuria is a rare disorder that is inherited as an autosomal dominant or recessive pattern. This condition is marked by the excessive excretion of simple sugars in the urine. The genetic mutations in the SLC5A2 gene play an important role in the etiology of this condition. The prognosis of this condition is good as it runs a benign course. The health care providers advise the patient to undergo routine urine and blood tests to keep the condition in check and also to rule out other complications.

Frequently Asked Questions

1.

Is Renal Glycosuria Considered a Serious Condition?

Renal glycosuria can be serious if it is a sign of an underlying condition such as diabetes, kidney disease, or hormonal imbalance. The seriousness depends on the underlying cause and the severity of the condition. It is important to seek medical evaluation if glycosuria is persistent.

2.

What Is the Diagnostic Process for Detecting Renal Glycosuria?

Renal glycosuria is diagnosed by testing the glucose level in a urine sample. A simple urine test can measure the amount of glucose in the urine and determine if levels are higher than normal, indicating glycosuria. Further evaluation, including blood tests, may be needed to determine the condition's underlying cause.

3.

Is It Possible to Cure Glycosuria?

The cure for glycosuria depends on the underlying cause. It may resolve independently if the glycosuria is caused by a temporary condition such as stress, diet, or hormonal changes. If the glycosuria results from a more serious underlying condition such as diabetes or kidney disease, treatment may be necessary to manage the condition and reduce glycosuria. Treatment may include medication, lifestyle changes, and monitoring of glucose levels. It is essential to seek medical evaluation to determine the cause of glycosuria and the appropriate course of treatment.

4.

Can Renal Glycosuria Be Reversed?

The reversibility of renal glycosuria depends on addressing the underlying cause. It may resolve independently if the glycosuria is attributed to temporary factors like stress, dietary changes, or hormonal fluctuations. However, if the glycosuria is linked to conditions such as diabetes or kidney disease, appropriate treatment may be required to manage the condition and reduce glycosuria. Treatment approaches may involve medications, lifestyle adjustments, and regular monitoring of glucose levels. 

5.

Does Glucose indicate a Kidney Infection in the Urine?

Glucose in the urine alone is not a definitive indicator of a kidney infection. A kidney infection, also known as pyelonephritis, is caused by bacteria and is characterized by symptoms such as fever, pain in the side or back, and cloudy or strong-smelling urine. The presence of glucose in the urine may indicate high blood sugar levels and can be a sign of diabetes or renal glycosuria. However, other tests must confirm a kidney infection, including a urinary tract infection (UTI) test. 

6.

What Is the Typical Glucose Level in the Urine for Those With Renal Glycosuria?

The normal range for glucose levels in the urine is 0 to 140 mg/dL. If the glucose levels in the urine are higher than normal, it may indicate glycosuria. However, it is important to note that elevated glucose levels in the urine can also signify other conditions, such as diabetes or kidney disease. A diagnosis of glycosuria can only be made after a thorough evaluation by a healthcare professional.

7.

Which Type of Diabetes Is Associated With Glycosuria?

Type 2 diabetes can cause glycosuria. In diabetes, high blood sugar levels can result in excess glucose excreted in the urine. This can cause glycosuria. In some cases, people with type 2 diabetes may not produce enough insulin, or their bodies may not effectively use insulin, leading to elevated blood sugar levels and glycosuria. It is important to seek medical evaluation if one has persistent glycosuria, as it may indicate an underlying condition such as diabetes.

8.

What Is the Significance of a 1+ Glucose Level in the Urine?

A urine test result of 1+ glucose means a small amount of glucose is present in the urine. This result is considered trace or low positive. Although it is not unusual to find small amounts of glucose in the urine due to factors like consuming a high-carbohydrate meal or experiencing stress, sustained or elevated glucose levels in the urine can indicate glycosuria. This condition may signal underlying health issues like diabetes or kidney disease.

9.

Can One Have Glycosuria Without Diabetes?

Yes, one can have glycosuria without diabetes. A range of conditions, such as hormonal imbalances, specific medications, and kidney disease, can contribute to glycosuria, characterized by glucose in the urine. While diabetes is a common cause of glycosuria, it is not the only cause. 

10.

What Steps Can One Take To Decrease the Levels of Glycosuria?

The approach to reducing glycosuria depends on the underlying cause. Here are some general measures that may help:
- Maintaining Healthy Blood Sugar Levels: If glycosuria is caused by diabetes, maintaining healthy blood sugar levels through proper diet, exercise, and medication can help reduce glucosuria.
- Healthy Diet: Eating a balanced diet low in sugar and carbohydrates can help regulate blood sugar levels and reduce glycosuria.
- Staying Hydrated: Hydrating adequately by consuming ample amounts of water can assist in eliminating excess glucose from the body and diminish the occurrence of glycosuria.
- Avoiding Triggers: Glycosuria can be triggered by specific foods, medications, and stress. Identifying and actively avoiding these triggers can be beneficial in minimizing glucosuria.

11.

Is Glucose in the Urine a Temporary Condition?

Yes, glucose in the urine can be temporary. Several factors can cause temporary glucose in the urine, including high-carbohydrate meals, stress, dehydration, and certain medications. In numerous instances, transient glucose in the urine tends to subside once the root cause is resolved. Nevertheless, if glucose in the urine persists or is accompanied by additional symptoms, it could signify an underlying condition like diabetes or kidney disease, and medical evaluation is recommended.

12.

What Is the Outcome of Glucose Present in the Urine?

A positive result for glucose in the urine means glucose is present at higher levels than usual. Elevated glucose levels in the urine can serve as an indication of various conditions, including:
- Diabetes: High blood sugar levels can cause excess glucose to be excreted in the urine, leading to glycosuria.
- Kidney Disease: Kidney disease can impair the ability of the kidneys to reabsorb glucose, leading to glucose in the urine.
- Hormonal Imbalances: Certain hormonal imbalances, such as those associated with pregnancy, can cause glucose in the urine.
- Certain Medications: Some medications, such as diuretics, can cause glucose in the urine.

13.

Is Glycosuria Considered Abnormal in All Cases?

When present in small quantities, glucose in the urine does not necessarily indicate an abnormal condition. It can be attributed to factors such as consuming a high-carbohydrate meal or experiencing stress. However, persistent or elevated glucose levels in the urine can indicate an underlying condition, such as diabetes or kidney disease, and is considered abnormal. 

14.

Is Glycosuria Responsible for Causing Urinary Tract Infections (UTIs)?

Glycosuria, or glucose in the urine, does not directly cause urinary tract infections (UTIs). However, glycosuria can increase the risk of UTIs by providing a source of food for bacteria that can cause diseases. Uncontrolled diabetes can create a conducive environment for bacterial growth that cause urinary tract infections (UTIs) due to high glucose levels in the urine.

15.

What Is the Typical Color of Urine in Individuals With Diabetes?

Diabetic urine can vary in color, depending on the glucose level in the urine. In people with uncontrolled diabetes, high levels of glucose in the urine can cause the urine to appear sweet or fruity-smelling and can change the color of the urine to a darker, amber color. This is because glucose in the urine can increase the concentration of glucose and other substances in the urine, which can cause a change in color. In some cases, glucose in the urine can also cause the urine to appear cloudy. 
Dr. Manzoor Ahmad Parry
Dr. Manzoor Ahmad Parry

Nephrology

Tags:

renal glycosuriakidney disorders
Community Banner Mobile
By subscribing, I agree to iCliniq's Terms & Privacy Policy.

Source Article ArrowMost popular articles

Do you have a question on

kidney disorders

Ask a doctor online

*guaranteed answer within 4 hours

Disclaimer: No content published on this website is intended to be a substitute for professional medical diagnosis, advice or treatment by a trained physician. Seek advice from your physician or other qualified healthcare providers with questions you may have regarding your symptoms and medical condition for a complete medical diagnosis. Do not delay or disregard seeking professional medical advice because of something you have read on this website. Read our Editorial Process to know how we create content for health articles and queries.

This website uses cookies to ensure you get the best experience on our website. iCliniq privacy policy