Renal disease, neuromuscular disorders, and urinary tract obstructions can cause low creatinine in children. However, creatinine levels may vary depending on a person’s age, gender, and health status. Usually, men have higher creatinine levels than women, and children have lower levels than adults (1) (2).
Creatinine is a waste product produced in the body during muscle metabolism. It is transported in the blood to the kidneys and eliminated from the body. Urine tests and blood tests help determine the amount of creatinine in the body.
Read this post to know the causes, symptoms, diagnosis, and treatment of low creatinine in children.
Causes Of Low Creatinine Level In Children
The normal blood creatinine level in children between three and 18 years is 0.5 to 1.0 milligrams per deciliter (mg/dL), and for children below three years, it is 0.3 to 0.7 mg/dL (1).
- Low muscle mass (occurs due to malnutrition, inadequate physical activity, neuromuscular diseases, etc.)
- Liver failure
- Insufficient protein in the diet (generally due to a strict vegetarian diet)
- Excessive weight loss
- Impaired renal functioniXA condition when the kidneys are unable to eliminate waste and maintain fluid balance
Furthermore, the creatinine clearance (urine creatine) level may drop due to the following causes (6):
- Kidney disease
- Blocked urinary tract
- Heart failure
Symptoms Of Low Creatinine Level In Children
- Poor posture, fatigue, and loss of muscle strength for low muscle mass
- Liver enlargement, itching, fatigue, and jaundice for chronic liver disease
- Being underweight or overweight, poor growth, lethargy, and tooth decay from poor nutrition
Diagnosis Of Low Creatinine Level In Children
Under typical conditions, it is advisable to assess creatinine levels on an annual basis (10). Two types of tests help diagnose the creatinine levels in children:
- Serum creatinine level: The blood creatinine level is measured through a blood test. If the level is lower than normal, it may indicate problems with the muscles, nerves leading to the muscles, liver, or nutrition (11).
- Creatinine clearance: This test indicates how well the kidneys remove creatinine from the blood and accurately detects kidney function issues. Creatinine clearance involves testing a blood and urine sample collected over 24 hours. The time of urine collection is an important factor for accurate diagnosis.
- Refrain from eating overnight
- Avoid meat for 24 hours
- Drink plenty of fluid for urine collection
Since low creatinine levels generally indicate muscle loss, further assessments such as a muscle biopsyiXA minor surgical procedure where a sample of tissue from a specific muscle is removed to diagnose muscle-related conditions , blood tests, and an electromyogramiXA device for capturing the electrical activity of skeletal muscles can determine the reason (13).
Treatment Of Low Creatinine In Children
Your child’s healthcare provider may advise treatments based on the causes.
- If a child has liver problems, medications, lifestyle changes, and surgery help treat the condition (14).
- In case of loss in muscle mass, medications, physical therapy, surgery, support of a walker and walking machines, and nutritional counseling are suggested (13). Physical activity is recommended for increasing the body’s serum creatinine level (15).
- If the creatinine level is low due to malnutrition, having a balanced diet by adding fruits and vegetables, meat, fish, eggs, starchy food, and dairy products will help control the condition (16).
- Creatine supplements may be given; however, such supplements have not yet been determined safe for children under 18 years. A study in 2012 found that 62 out of 1103 middle and high school students in the US used creatine supplements, but as their safety is still questionable, intake may lead to further problems (17).
High Creatinine Levels: Causes And Symptoms
- Chronic kidney disease
- Muscle disease
- Blocked urinary system
- Excess protein in the diet
- Overactive thyroid
- Congestive heart failure (the heart works harder than normal to pump blood)
- Pediatric medicines
High levels of serum creatinine may indicate renal disease without noticeable symptoms in the beginning. However, as the disease progresses, it produces these symptoms (4) (12):
- Less urine
- Dark urine
- Swollen feet, face, and eyes
- Loss of appetite
Frequently Asked Questions
1. What level of creatinine indicates kidney failure in a child?
Normal creatinine levels for each child can vary depending on their body size. So, the creatinine levels indicating renal failure can also vary in children. Pediatric nephrology specialists (kidney specialists) assess the creatinine levels with child size to establish the diagnosis. For example, if the normal creatinine level for a child with a specific size is 0.5, the child’s kidneys are in 100 percent working condition. Kidney function can be half for the same child if the creatinine level rises to one. If the creatine is between one and two, kidney function would be only 25% (18).
2. Does drinking water help creatinine levels?
Drinking enough water can reduce creatinine levels. But, this will not improve kidney function. That means drinking water only gives you low creatinine levels on tests and does not make a difference in existing kidney problems such as kidney damage or kidney injury. Excess water intake can also be harmful as low water intake (19).
3. How often should a child’s creatinine levels be monitored?
There is no ideal time to monitor creatinine levels. However, you may do your child’s blood and urine test routinely every year. In this way, it is believed that any early signs of illness may be effectively diagnosed.
Low creatinine in children may occur due to several reasons. It is not considered a disease on its own but usually indicates an underlying health condition such as thyroid, diabetes, low muscle mass, or issues related to kidney health. Therefore, parents should immediately consult their child’s pediatrician if they notice symptoms related to these conditions. The treatment process for low creatinine levels will be based on the diagnosis. It is advised that children should follow the treatment procedure diligently to speed up their recovery.
Infographic: More About Creatine Supplements
The use of creatine supplements in children has not been thoroughly studied. However, these supplements are promising in providing benefits to children with low creatinine levels and improving athletic performance. The infographic below summarizes the benefits and safety of such supplements.
- Impaired renal function can cause a drop in serum (blood) and urine creatinine levels.
- Fatigue, loss of muscle strength, poor development, lethargy, tooth decay, etc., are signs of low creatinine levels in children.
- Urinalysis and creatinine blood tests can diagnose its levels at an early stage.
- Even if there are no symptoms at first, high serum creatinine levels can indicate renal issues.
- Creatinine (Blood).
- Urine Test: Creatinine.
- Should we pay more attention to low creatinine levels?
- Here’s How To Check If Your Kidneys Are Working Fine.
- Marlies Ostermann et al.;(2016); The two sides of creatinine: both as bad as each other?
- Creatinine and Creatinine Clearance.
- Low muscle tone.
- Liver Disease.
- Nutrition – school-age to adolescence.
- Creatinine and eGFR – Measuring Kidney Function; United States Department of Veterans Affairs
- Creatinine blood test.
- Creatinine Clearance Test.
- Muscular Dystrophy.
- Liver Failure in Children.
- Alessandra Calábria Baxmann et al.; (2008); Influence of Muscle Mass and Physical Activity on Serum and Urinary Creatinine and Serum Cystatin C.
- Robert Cooper et al.; (2012); Creatine supplementation with specific view to exercise/sports performance: an update.
- How Kidneys Work.
- My serum creatinine level is 1.17. Will drinking more water lower it?.