Diabetes mellitus type 2 (DM 2) was till recently considered a disease of adult age. The pandemie of obesity in the U5A in the nineties caused that in some American centres DM 2 accounts for as much as one quarter of netyly diagnosed diabetcs in the group of 10 -17-year-olds. 5imilar reports come from some other countries. The majority of patients are asymptomatic, some cases are however manifested by osmotic symptoms, rarely by ketoacidosis. Differentiation of DM 2 from DM 1 may be difficult in children. For DM 2 obesity is typical, and a family-history of DM 2, laboratory and clinical manifestations of insulin resistance, possibly negative islet antibodies. In some patients at first insulin treatment may be necessary, then it is however better to change to metformin treatment which facilitates weight reduction when the patients are on a strict reducing diet. During the last year authors diagnosed DM 2 in two adolescent patients - a 16-year-old girl with a body weight of 103 kg and BMI 35 kg/mZ with an accidental finding of glycosuria and hyperglycaemia of 19 mmol/1, and a 15-year-old boy with a body weight of 170 kg and BMI of 58 kg/mZ with a diabetic oGTT curve. In both there were clinically striking foci of acanthosis nigricans, and high insulin secretion was proved. Both were treated by metformin and a reducing diet. The favourable effect of treatment depended on cooperation and weight losses. DM 2 is a new phenomenon in child diabetology. Due to the advancing worldwide pandemie of obesity it may develop roto a serious health issue as the patients have a high risk of early development of chronic complications of diabetes.

        Key words: diabetes mellitus type 2, children, obesity, insulin resistance, oral antidiabetics