Interferences in laboratory tests: diagnostic criteria for diabetes mellitus and major hypoglycemic agents

Abstract

Diabetes mellitus (DM) is among the most significant chronic conditions of health. Current diagnostic criteria for DM suggest the following laboratory tests: fasting plasma glucose, glycated or glycosylated hemoglobin, oral glucose tolerance test, fructosamine, insulin, C-peptide, glucagon. This laboratory tests may present drug interferences, which are physiological or analytical. It was possible identify 30 drugs or group of drugs that have evidences of interfering in the major diagnostic tests of DM according reviewed literature. It is important to note that virtually in its entirety these drugs interfere in the blood glucose levels, and 81.5% of these contribute to increase these values. These drugs include OTCs (over-the-counter drugs), as paracetamol and acetylsalicylic acid, and steroidal anti-inflammatory, as dexamethasone and prednisolone, extensively used in the drug therapy. Likewise, drugs used for treatment of diabetic patients included in the RENAME as NPH insulin (neutral protamine Hagedorn), regular human insulin, glibenclamide, glicazide and metformin hydrochloride may interfere in the laboratory tests. Early diagnosis and appropriate treatment are needed in order to prevent major damage for patients presenting this under-diagnosed complex disease. In this context, drug interferences are significant findings in the laboratory tests that evaluate DM and should be acknowledged by involved healthcare professionals.