My two-year-old was diagnosed with type 1 a little over a year ago. For over a day, she has had extreme lows with no changes in her diet, insulin intake, exercise, etc. She has not been exhibiting any signs of illness– no ketones, fever, cough, etc. She has not had any short acting insulin all day but is eating normally and still under 150 mg/dl [8.3 mmol/L]. My diabetes team seems to think she is getting sick or is going through a growth spurt. I am not convinced. What else could be causing these lows? Her two last A1cs were 9.1 in August and 8.6. She gets two injections of Lantus, 1.5 units in the morning and 1 unit in the evening. However, we have backed off on the evening dose to 0.5 unit for one week.

It sounds like you have done a nice job trying to find contributing factors to your daughter’s “lows.” Your letter also indicates that your daughter now receives only long-acting Lantus without any other short- or rapid- acting insulins.

I also doubt the “growth spurt” explanation, as insulin requirements often INCREASE with increasing size. What has her weight and length done since she was last seen?

Also, I would advise that you look for patterns: just one day of lower glucoses does not help establish any persistence or pattern to glucose values.

So, let’s first review the basics of basics: blood glucose maintenance hinges primarily on three things: insulin levels, calorie (food) intake, and calorie utilization (activity, mostly). If your daughter now seems more sensitive to insulin with lower glucoses while receiving the same (or even lower) doses of Lantus insulin, then attention next needs to focus on her calorie intake and use.

Presuming that she is eating at least as much as she was before you noted any persistent trend of lower glucose values, then I would be concerned whether she is absorbing the nutrients well from her intestinal system. In my experience, it is fairly common for “out-of-nowhere” low glucoses to be followed some days later by a diarrheal illness. This may be what your own diabetes team meant when they voiced concern that she might be getting sick. In addition, there is an illness called celiac disease, an autoimmune inflammation of the intestine, which occurs in nearly 10% of type 1 patients, that also could interfere with calorie absorption. Age two is somewhat young for celiac disease to develop but your team will likely screen for that if these lower glucose values and increased insulin sensitivity issues persist.

What about increased calorie utilization? If she were systemically ill (for example an illness with a fever or other infection), she might be using glucose more rapidly. Obviously, if she were more active with a new children’s activity or group, that could also lead to lower glucoses — and those lower values might not manifest until several hours later.

Another aspect of glucose control relates to the body’s other systems, including hormonal systems, that influence blood glucose levels. Examples (not a complete list) include growth hormone, cortisol, epinephrine (adrenaline), thyroid hormone, and many others. In addition to celiac disease, cortisol (also from the adrenal glands) and thyroid issues also have higher incidence rates in patients with type 1 diabetes. These conditions are commonly screened for periodically in type 1 patients and your team will screen for them, if they haven’t already, and will likely screen sooner if the lower glucose values persist.

But, having written all the above, I want to clarify that the glucose value of “under 150 mg/dl [8.3 mmol/L]” doesn’t sound low to me at all – even for a child this age. A NORMAL glucose (diabetic or not) is about 60 to 100 mg/dl [3.3 to 5.6 mmol/L], and most clinicians do not get concerned until the glucose value is less than about 50 mg/dl [2.8 mmol/L]. On the other hand, we often give our patients/families “target glucose ranges” and perhaps your diabetes team has been targeting a high range of about 150 to 200 mg/dl [8.3 to 11.1 mmol/L]. That would be an UPPER LIMIT – probably not to be the constant goal. So, talk to your diabetes team for clarification of what they are targeting for your daughter’s glucose values: what would be too low or too high (on a recurring basis) that they would want to make adjustments?

Finally, be certain that you have a working glucagon emergency kit and that you are familiar with it’s use for treating SIGNIFICANT lows. Your daughter should also have a diabetes medical identification that she wears around a wrist or ankle (I wouldn’t advise a necklace in this age group).

Good luck and let us know what you learn.

DS