Proinsulin

Clinical Use

Use

Proinsulin is synthesized in the pancreatic beta cells as a precursor to insulin. Elevated levels of proinsulin are associated with various conditions, such as benign or malignant β-cell tumors of the pancreas, endocrine pancreatic tumors associated with multiple endocrine neoplasia type 1 (MEN-1), and impaired glucose tolerance. High levels can also be a risk factor for developing non-insulin-dependent diabetes mellitus (NIDDM). Elevated proinsulin levels can be observed in patients with chronic renal failure, cirrhosis, or hyperthyroidism.

Special Instructions

Not provided.

Limitations

Proinsulin concentrations are typically low, making it important to handle specimens properly to avoid degradation. Nonfrozen specimens, nonserum specimens, gross hemolysis, and gross lipemia can cause rejection. The turnaround time may be longer if additional confirmatory or reflex tests are required. Testing schedules can vary which may affect the time to release results.

Test Details

Methodology

Immunoassay (EIA)

Biomarkers

Proinsulin

Protein

Proinsulin

Concentration / Level • Quantitative (Continuous) (e.g., copies/mL, % expression)

LOINC Codes

Order Codes

27882-0 - Proinsulin SerPl-sCnc

Result Codes

27882-0 - Proinsulin SerPl-sCnc

Result Turnaround Time

3-5 days

Specimen

Serum

Volume

0.6 mL

Minimum Volume

0.4 mL

Container

Red-top tube or gel-barrier tube

Collection Instructions

Transfer the serum into a Labcorp PP transpak frozen purple tube with screw cap (Labcorp No. 49482). Freeze immediately and maintain frozen until tested. To avoid delays in turnaround time when requesting multiple tests on frozen samples, please submit separate frozen specimens for each test requested.