Overview
Insulin Deficiency Creates the Clinical Pattern
Type 1 diabetes is caused by autoimmune destruction of pancreatic beta cells.
Type 1 diabetes is caused by autoimmune destruction of pancreatic beta cells. The child therefore has an absolute insulin deficiency: glucose may be abundant in the bloodstream, but it cannot enter insulin-dependent cells effectively for use or storage. The resulting pattern is logical. Rising glucose exceeds the kidney’s ability to reabsorb it, so glucose pulls water into the urine. Polyuria, nocturia or new enuresis, polydipsia, dehydration, and fatigue follow. Because the body cannot use glucose normally, it breaks down fat and muscle, producing weight loss despite hunger. Without enough insulin, fat breakdown also produces ketones. Ketones are acids. Their accumulation causes diabetic ketoacidosis (DKA), which can progress from abdominal pain and vomiting to deep, rapid Kussmaul respirations, altered consciousness, shock, and cerebral edema. A child with type 1 diabetes needs insulin every day, including during illness and reduced oral intake. Food intake may fall during a viral illness, but stopping basal insulin allows unchecked ketone production and can rapidly precipitate DKA.
