Type 1 diabetes is a chronic progressive autoimmune disorder with complex, polygenic susceptibility. Environmental factors which are poorly defined also contribute to the pathogenesis. This disease is characterized by lymphocyte infiltration into the islets of Langerhans in the pancreas, leading to inflammation and selective destruction of the insulin-producing beta cells resulting in hyperglycemia.

The latest incarnation of polymerase chain reaction, Digital PCR, takes three decades of development in enzyme chemistry and assay design and applies them with formidable precision and sensitivity.

Hemoglobin A1C is one of the analytes most commonly measured in clinical laboratories in patients with diabetes mellitus. Physicians use Hemoglobin A1C to monitor long-term glycemic control, adjust therapy, and predict complications of diabetes. It was recently added as a criterion for diagnosis of diabetes.

Although standardization of barcodes and label formats has lowered the number of mislabeled specimens in clinical laboratories, it remains a potential source of pre-analytical error. Published error rates of mislabeled specimens range up to as high as just over 1 percent.

On the cover this month: Activated platelets. These irregularly shaped blood

components are vital for the normal clotting process. However, platelets also play

a role in blood clot formation on arterial stents or on ruptured atherosclerotic

plaques, leading to blockage of blood flow and tissue ischemia. For some patients,

antiplatelet agents must be used to prevent arterial thrombosis. During therapy,

platelet function tests are used to monitor response. Newer approaches to

monitoring coagulation, such as viscoelastic coagulation testing, are being

introduced. Controversy exists surrounding the tests for monitoring response to

antiplatelet therapy or for guiding transfusion decisions in critically ill patients.

This issue of Clinical Chemistry contains a Q&A in which 4 experts discuss how

they define aspirin and clopidogrel response, what platelet function tests are used

at their institutions, the role of the laboratory in guiding antiplatelet therapy, and

what tests they believe have the greatest potential to predict the risk of bleeding

during invasive procedures.

Gestational diabetes mellitus is often defined as any degree of glucose intolerance during pregnancy. Fetal complications and adverse outcomes for both the fetus and the mother are important concerns in gestational diabetes.

Acute kidney injury is an important health problem. Patients who develop acute kidney injury have increased in-hospital mortality, and if they do survive, they still suffer long-term increased morbidity and mortality. For that reason there has been great interest in the development of biomarkers that could identify kidney injury in its earliest stages, at a time when interventions might be more successful.

In March of 2013, the ACMG, The American College of Medical Genetics and Genomics, issued a clinical laboratory guideline for the reporting of incidental findings observed through exome and genome sequencing, including the ethical implications of reporting these incidental findings.

The discovery phase of proteomics is essential for the identification of suitable markers for exploration and validation of promising new clinical tests. But can researchers be certain if what they believe they are measuring is in fact what they are actually measuring?

This is the February 2014 issue of Clinical Chemistry, Volume 60, Issue 2.