Liver
Albumin
Albumin is the most abundant protein in blood plasma and is synthesised solely by the liver, where it maintains plasma oncotic pressure and transports hormones, calcium, drugs and other molecules. At the point of care it is measured within liver and comprehensive metabolic panels to give a rapid snapshot of hepatic synthetic function and overall protein status.
Why it is measured
Albumin reflects the liver's synthetic capacity and is also shaped by nutrition, inflammation and fluid balance, so a low result can be associated with chronic liver disease, protein loss or acute illness. Having it available at the bedside supports earlier clinical conversations without waiting for the central laboratory.
| Typical range | Approximately 35 to 50 g/L (3.5 to 5.0 g/dL) in adults. Ranges vary by method: bromocresol green (BCG) assays tend to read slightly higher than bromocresol purple (BCP), so always interpret against the analyser's own quoted reference interval. |
|---|---|
| Sample | Whole blood, serum or plasma; a fingerstick or small venous sample of roughly 70 to 100 microlitres is loaded onto the analyser's reagent disc or cartridge. |
| Turnaround | Around 7 to 15 minutes from sample loading to printed result on most bench-top POCT chemistry analysers, varying by instrument and panel selected. |
Point of care devices that report it
- Abbott Piccolo Xpress (Comprehensive Metabolic Panel and Liver Panel Plus reagent discs)
- Seamaty SD1 / SMT-120 dry-chemistry analyser (liver function panel, ALB)
- Samsung LABGEO PT10 (Hepatic Panel cartridge)
Questions, answered
Why might albumin be low if there is no known liver disease?
Albumin can fall for reasons other than reduced liver synthesis. It behaves as a negative acute-phase protein, so it commonly drops during infection or inflammation, and it can also be lowered by poor nutrition, protein loss through the kidneys or gut, and dilution from intravenous fluids. This is general educational information rather than a diagnosis, and results should be reviewed by a clinician alongside the full clinical picture.
Do point-of-care albumin results match the central laboratory?
POCT chemistry analysers generally correlate well with laboratory methods, but small differences arise from the dye-binding chemistry used (BCG versus BCP) and from calibration. For monitoring, it is good practice to follow trends on the same platform and to confirm unexpected or clinically important results with the central laboratory.
Can sampling technique or hydration affect the albumin reading?
Albumin is relatively stable and is not greatly affected by fasting, but a prolonged tourniquet, upright posture and dehydration can raise the apparent concentration, while over-hydration can lower it. Following the analyser's instructions for sample type, volume and handling helps keep results reliable.