Question from Tustin, California, USA:

My three year old daughter has a history of immune dysreguation and specific antibody deficiency (pneumococcal). This began at around six months of age. After two years of “unclear” chest x-rays, six months of IVIG treatment did clear them for three months. Since then, in October 2005, she was brought back to the Emergency Room due to lethargy, frequent urination, excessive thirst, dehydration and difficulty breathing. She was diagnosed again with bilateral pneumonia but, this time, was throwing up from what they say was LARGE Ketones, low blood sugar and low carbon dioxide. Ketotic hypoglycemia was diagnosed.

We then were referred to a pediatric endocrinologist at Children’s Hospital of Orange County “CHOC” (a very good team) and they asked us to start monitoring her blood sugar which goes as high as 280 mg/dl [15.6 mmol/L] after eating but low fasting numbers, 72 to 83 mg/dl [4.0 to 4.6 mmol/L] with intermittent lows with symptoms after ingesting sugar. Her range of blood sugar swings from low 70s to 180s (mg/dl) [3.9 to 10.5 mmol/L] a lot. They had us change her diet, which does help with the bigger swings but she still shoots high and low occasionally with symptoms on both ends of the spectrum. She goes as low as 50 mg/dl [2.8 mmol/L].

She has been tested for all diabetic antibodies (GAD and Insulin AB) and they were negative. Her initial metabolic disorder tests are normal also. Her fasting blood insulin level was <2 uIU/ml with a 72 mg/dl blood sugar [4.0 mmol/L]. She also had normal ACTH and Cortisol levels at that time. The pediatric endocrinologist team is wonderful, but admits they are a little "stumped". They recommended we keep her on the diet, continue checking her sugar and check ketones with illness. She is having more metabolic work-up done because they feel her dysregulated blood sugar may have more to do with that. If the ACYL-Carnitine tests come back normal, they have suggested an in-hospital monitored five hour glucose type test measuring glucose, insulin and lactic acid intermittently under close supervision. I am wondering if you have anything else to add that we may be overlooking? She is followed by the hospital's pulmonary, immune deficiency and endocrine clinics and we are all concerned because, despite all treatment efforts, she continues to have cyclic fatigue, stamina issues, illness, yeast infections, and periods of frequent urination (wetting the bed) and excessive thirst. Her little body is tired. (thyroid levels were also normal) What do you think about the low insulin level -- <2 where the laboratory range was 6 to 27 (normal)? This was tested and retested twice. If insulin is low, and blood sugar low, what hormone is compensating for the insulin? I understand most people always have a little insulin in their system.