Question from Laguna, Philippines:

My four-year-old son was hospitalized due to vomiting, abdominal pain/distention and low grade fever occurring 24 hours prior to admission. At first, intestinal obstruction was entertained. But x-rays and ultrasound failed to show mechanical obstruction, only ileus with bowels grossly distended. On urinalysis, however, they found ketones +2. Ketones were also in his serum. Capillary blood glucose (CBG) was 160 mg/dl [8.9 mmol/L]. No acidosis on arterial blood gas. Juvenile diabetes mellitus was entertained, with impending diabetic ketoacidosis (DKA). Insulin drip was started. In the 10 days he stayed in the hospital, his CBG was always below 120 mg/dl [6.7 mmol/L], dipping to as low as 35 mg/dl [2.0 mmol/L) when insulin was shifted to subcutaneous. He was on NPO (nothing by mouth) for seven days for bowel rest, so aside from the TPN (total parenteral nutrition), D10, I.V. push, was given to increase his blood sugar. Feeding was gradually resumed three days prior to discharge.

On discharge, the instruction was to give 8 units of Humulin N before breakfast and 4 units before dinner, but to withhold for CBG values below 80 mg/dl [4.5 mmol/L]. It has been 10 days since discharge, but I haven’t given any insulin shots since his sugars were always in the 70s and 80s mg/dl [3.9 to 4.9 mmol/L], with him eating like he always did but only without the sweet foods. He is back to his usual activities. He has no history of major illnesses nor hospitalization. He experienced no sudden weight loss. Prior to hospitalization, he never showed any symptoms like polyuria, polyphagia, polydipsia. Even upon discharge, no such symptoms were noted. Could he have been misdiagnosed? His appetite was off two days prior to admission. Could the starvation and the dehydration have caused the ketones to appear in his urine and serum? Could it have been just gastroenteritis with resulting ileus? Or, was there really underlying diabetes mellitus hence the rapid deterioration of his gastrointestinal infection? Or, was it DKA already hence the abdominal pain and vomiting? Can you say it is DKA if the ABG showed normal pH??