December 14, 2000
Complications
Question from Los Angeles, California, USA:
My 11 year old son has had type 1 diabetes for the past year and a half. His doctor is the author of a book. My son’s HbA1c was 6%, and he maintains sugars of 80-110 mg/dl [4.4-6.1 mmol/L] most of the time, except sometimes at bedtime or in the morning.
I have been told that children, especially in the early stages of diabetes, do not have gastroparesis, but a study (R and R interval) done by the doctor showed that my son has an abnormal profile that could indicate gastroparesis. Also, my son has the classic pattern of blood sugar associated with gastroparesis.
Here are two examples. His glucose was 90 mg/dl [5 mmol/L] before dinner. I gave him his regular insulin (about 3.5 units) and his usual dinner, except he ate chicken (chicken and meat are harder to digest). After one hour, his sugar was 35 mg/dl [1.9 mmol/L]. We used glucose to correct it to 90 mg/dl [5 mmol/L]. An hour later, it was 50 mg/dl [2.8 mmol/L]. We used more glucose to correct it again. An hour later it was 60 mg/dl [3.3 mmol/L]. Again, we used a precise amount of glucose (1 gram raises his sugar 10 points, so that a 4 gram tablet will raise him 40 points). His morning glucose was 204 mg/dl [11.3 mmol/L] with no snack and his usual dose of U at bedtime. We assume that the food simply wouldn’t leave his stomach so that his sugar kept going low until the middle of the night or early morning when it finally emptied, and there was no insulin present to “cover” the food. Thus the “unexplainable” high in the morning.
Another example was last night. His pre-dinner glucose was 80 mg/dl [4.4 mmol/L]. I gave him his usual insulin and meal. By bedtime, his sugar was 328 mg/dl [18.2 mmol/L]. We hypothesize that his stomach emptied four hours after dinner when his insulin had almost finished working. We use pretty similar meals and insulin, and we cannot figure out why there would be such a difference. The only answer we have is that he took his Propulsid [a prescription medication for gastroparesis] very late, and it did not have time to work. His doctor recommends Propulsid before dinner. When he takes the Propulsid 30-45 minutes before dinner, his profile is better. (By the way, we rarely have these issues at after breakfast or lunch, but occasionally we do.)
Do you have any other children with similar issues of gastroparesis? I have read many of your question/answers that talk about unexplained glucose readings in the morning. Could any of these highs be due to slow digestion?
Answer:
It would be a mistake to comment too emphatically on your son’s story without knowing a great deal more of his clinical history, his insulin type and dose, etc. However, I do think that there could be another explanation for what you describe in the evenings. His blood sugar control seems to have been excellent which is the important thing. However, since Propulsid (cisapride) has now been withdrawn from the market (Cleve.Clin.J.Med. 67:471,2000), except for special cases, It is perhaps worth checking with your son’s physician as to whether or not your son had an antibody test at the time of diagnosis to determine if he has type 1A or autoimmune diabetes or type 1B in which some 50% of cases can manage with little or no insulin after a few months. It would also seem to be important to check how sure the diagnosis of gastroparesis is because it is very rare at this stage in diabetes in someone with such excellent control. I am not familiar with the ‘R & R interval’ having usually relied on some radiological procedure.
However, It did seem to me also that your son could be on a significantly low dose of insulin. With only 3.5 units of Regular insulin, he seems to have had significantly low blood sugars for at least two hours after the evening meal. The subsequent rebound to 204 mg/dl (11.3 mmol) could have been from counterregulatory hormones. The second episode is a little harder to explain, but again, with a delay in giving the cisapride, he might have had an even lower dip in his blood sugars, and, in consequence, an even higher rebound. Such responses would be as much, if not more, consistent with type 1B diabetes in the phase of waning insulin need as with a rather unlikely gastroparesis.
Under these circumstances, you might perhaps consider getting a second opinion from a recognised pediatric diabetes care team.
DOB