Carbohydrate Metabolism

All relevant functional tests are explained with a detailed presentation of indications, contraindications, side effects, test preparation, framework conditions, specific instructions for the actual test execution, and the interpretation of test results. Specific normal ranges and cut-off values are always provided, even for special situations (gender, age, BMI, puberty phases, cycle phases, acute illnesses, medications, etc.). A special feature is the emphasis on test preparation, execution, and interpretation, as well as the interdisciplinary nature. The oral glucose tolerance tests (OGTT) offer numerous indications, threshold values, and differ regarding the compartment used for blood sampling. This chapter provides clarity for each individual OGTT, including, for example, tests during pregnancy. Additionally, the diagnostics of insulinoma and acromegaly, as well as the endocrine pancreatic function tests, are covered. The role of C-peptide and intact proinsulin is presented. The altered units and measurement methods of the HbA1c value in its new role as a diagnostic criterion for diabetes mellitus are explained in detail. The specific therapy target parameters are also explained.