Varying clinical presentations at onset of type 1 diabetes mellitus in children - epidemiological evidence for different subtypes of the disease?

: Objective: On the basis of 2121 case observations between 1987 and 1997, we describe the clinical and laboratory characteristics of diabetes mellitus type 1 at its onset. Our objective is to analyze whether clinical presentation follows a uniform pattern or whether there is evidence for different subtypes. Research design and methods: Thirty‐one pediatric hospitals and one diabetes center in Baden‐Wuerttemberg (BW), Germany, participated in this study. The hospital records of 2121 children below 15 yr of age were examined retrospectively. Statistical analysis was done after logarithmic transformation into a normal distribution. Results: The average duration of symptoms was found to be 15.2 d (95% CI (Confidence Intervals) = 14.3–16.1) ranging between 2.0 and 180 d (95% central range). The most frequent symptoms were polyuria and polydipsia; 7.2% presented with altered level of consciousness. The mean blood glucose value was 407.9 mg/dL (95% CI = 400.0–416.0), corresponding to 23.3 mmol/L (95% CI = 22.8–23.8). The median pH value was 7.35 (95% CI = 7.34–7.36), and the median base excess was −5 mmol/L (95% CI =−5 to −4). The younger patients had a shorter duration of symptoms and suffered most frequently from ketoacidosis. Conclusions: Although the symptoms of diabetes at its onset follow a uniform pattern, the clinical presentation and duration of symptoms indicate that there may be various forms of type 1 diabetes.