[Difficult diagnosis in a 17-year-old patient: Type 1 diabetes? Type 2 diabetes? Or "double diabetes"?].
MEDICAL HISTORY AND CLINICAL FINDINGS: We report on a 17-year-old boy with elevated blood glucose levels, elevated liver enzymes and obesity (BMI 32.3 kg/m2). Clinical examination showed acanthosis nigricans and a vitiligo. The rest of the physical examination was without pathological findings.


METHODS
The HbA1c value was 8.6 % (71 mmol/mol), and postprandial C-peptide showed a maximum level of 1.3 nmol/l. The type 1 diabetes-associated autoantibodies against protein tyrosine phosphatase IA-2 and zinc-transporter-8 were positive, while autoantibodies to glutamic acid decarboxylase and insulin were negative. There was no ketonuria. Ultrasound showed steatohepatitis.


METHODS
Under therapy with metformin up to 2×1 g, blood glucose levels and liver enzymes normalized after a few weeks. After two months, the HbA1c value was 6.0 % (42.1 mmol/mol), and a weight loss of 5 kg was recorded.


CONCLUSIONS
In obese adolescent patients with diabetes, a clear classification right from the beginning is not always possible. Characteristic findings of type 1 and type 2 diabetes may be present simultaneously. In the presented patient, monotherapy with metformin was sufficient in the first year. Close monitoring is essential to detect the transition to insulin dependence in time.
Kinderklinik München Schwabing - Klinik und Poliklinik für Kinder- und Jugendmedizin, Klinikum Schwabing, StKM GmbH und Klinikum rechts der Isar (AöR) der Technischen Universität München, München.
K
K
Warncke
Kinderklinik München Schwabing - Klinik und Poliklinik für Kinder- und Jugendmedizin, Klinikum Schwabing, StKM GmbH und Klinikum rechts der Isar (AöR) der Technischen Universität München, München.
I
I
Engelsberger
D000293:Adolescent; D001323:Autoantibodies / Q000097:blood; D001786:Blood Glucose / Q000378:metabolism; D002096:C-Peptide / Q000097:blood; D027682:Cation Transport Proteins / Q000276:immunology; D015897:Comorbidity; D003922:Diabetes Mellitus, Type 1 / Q000097:blood* / Q000175:diagnosis*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000175:diagnosis* / Q000188:drug therapy; D003937:Diagnosis, Differential; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use; D008297:Male; D008687:Metformin / Q000627:therapeutic use; D063766:Pediatric Obesity / Q000097:blood / Q000150:complications; D054635:Receptor-Like Protein Tyrosine Phosphatases, Class 8 / Q000276:immunology; D000075703:Zinc Transporter 8
D001323:Autoantibodies; D001786:Blood Glucose; D002096:C-Peptide; D027682:Cation Transport Proteins; D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents; D008687:Metformin; D054635:Receptor-Like Protein Tyrosine Phosphatases, Class 8; D000075703:Zinc Transporter 8; C492522:SLC30A8 protein, human; C517652:hemoglobin A1c protein, human