Wednesday, August 24, 2016
Very puzzling - Type 1 seems to be producing
I know this is a long shot for several reasons among which is I`m sure you are very busy. All I`m looking for is your opinion. Should you respond I will be forever grateful. I also understand that for "medical advice" you would actually need to meet and observe the patient. That`s why I am just looking for a very informal opinion.
My wife is 29 and has Type 1 Diabetes since she was 5. She has typically been on Lantus and Humalog. In the last month she was not formally diagnosed with, but was thought to have had, swine flu. After she got through that she was admitted to the hospital with blood glucose of 26 (mmol/L) and moderate ketones. After IV rehydration she was fine and sent home that night. Since then she has been experiencing frequent episodes of hypoglycemia, with two of them manifesting in seizures. Through working with the Diabetes Education Centre and wearing a Continuous Glucose Monitoring sensor, she was told to reduce her insulin intake. After about 1 1/2 weeks of reducing and working with insulin levels she is off all insulin. She is at the point where if she takes any insulin at all it pushes her into these extreme lows. Aside from the CGM sensor she had in we have monitored her blood glucose with a standard lab calibrated glucometer.
I will give two examples of what we`ve been seeing. Just the other day we went out for supper and we both had desert. About 45 min. after the meal she was about 18.6 mmol/L. After about 90min of sitting on the couch and watching tv it was down to 6.1 mmol/L. Last night before bed she tested at 11.0. Upon awaking at 6:45am she was 24.0 and went back to bed. At 10:30am she was 7.0. For most of the day her blood glucose falls in the 4.0-8.0 mmol/L range except for obviously after a meal high in carbs. The doctors and all the nurses at the Diabetes Education Centre are baffled. We are awaiting her appointment with a Diabetes specialist. From everyone`s reactions, I am assuming this kind of thing does not happen all the time. (at this time we are still awaiting the results of the typical C-Peptide tests)
The story suggests either a marked reduction in insulin requirements and either some insulin production by her own body or, if she got really dehydrated with the flu, conceivably some mobilization of some insulin that was injected in the past and not well absorbed from previous injections (the extent to which that is possible is going to be some what controversial and depends very much on the time elapsed from last insulin administration). Some may raise the question whether this means she has an insulin producing tumor and I suppose that needs to be ruled out but it is extremely unlikely. The thing that is relatively new that needs to be considered (and is more likely than an insulin-producing tumor)is whether or not her diabetes truly fits the definition of type 1 or whether she could have a relatively rare form that presents at a young age (like type 1) but is really due to a different cause, e.g. a genetic form with a mutation in the structure or secretion regulation of the insulin gene. It is key that c-peptide be evaluated in relation to the blood sugar and quite possibly in response to a stimulus to insulin secretion.
Robert M Cohen, MD
Professor of Clinical Medicine
College of Medicine
University of Cincinnati