October 10, 2004
Hypoglycemia
Question from Sharon Springs, New York, USA:
My six year old son recently had a fasting blood test. The results were 84 mg/dl [4.7 mmol/L] and considered normal. I am not sure if I should ask for further testing.
My concerns are that, after he eats, he often becomes anxious, excited and irritable. We also see behaviors about two to three hours after a meal, which may include anger and/or excessive laughing. During these times, if we provide him with crackers or other foods he seems to improve. Other symptoms/concerns include an increase in these behaviors if the foods that he eats are sandwiches, corn flakes, juice boxes, strawberries, or carrots. He has eczema, has increased his drinking, but not urination, has complained about headaches and tingling in his finger, has “pains” in his extremities after consuming foods high in corn derivatives, has cramps in his feet, has had surgery to repair hydronephrosis (kidneys function at about 60 to 70%) and has what I think is a significant family history for diabetes. His grandfather and three great-grandmothers had type 2 and two great uncles had type 1. Two aunts had gestational diabetes.
My son has always been at the 50th percentile on the growth chart. His diet is limited due to food allergies to milk, eggs and tree nuts. I have always thought he had an intolerance to corn due to the increase in behaviors and eczema when he eats foods that contain corn, but now I am wondering if he has hypoglycemia – reactive or fructose related? He eats a significant amount of pasta and fruits and we have noticed that when he eats more protein, he is better for a longer period of time. Would the fasting test be enough to determine a hypoglycemia diagnosis or should I pressure the doctor to do further testing since my concern has to do with following eating?
Answer:
I agree that the symptoms are consistent with hypoglycemia. But they are not SPECIFIC for hypoglycemia. You should continue to discuss matters with your pediatrician.
The way to establish whether any symptoms are glucose related is to test the glucose during the symptoms. Logical, huh? You can screen for this using a small glucose meter that patients with diabetes use. If the screening does suggest hypoglycemia, your pediatrician or, after a referral to a pediatric endocrinologist, should want to then try to determine the cause of the hypoglycemia. This would typically involve a series of blood tests and might involve a hospitalization whereby glucose levels are serially measured to various times during a supervised prolonged fast and in relation to meals. An oral glucose tolerance test (OGTT) , done correctly, might also be helpful, but often is not.
A normal fasting glucose does not exclude your child’s symptoms being due to hypoglycemia.
Finally, assuming no serious metabolic disturbance as a cause of recurrent hypoglycemia, often the easiest first line treatment is to change the dietary patterns to avoid (read virtually eliminate) “simple” sugars and add more protein and “complex” carbohydrates. But, I would not advise you to do this without proper input and assessment by your pediatric healthcare team.
DS
