Specimen Collection

Sample stability : _{(source: Roche UIBC package insert)}

• 4 days at 15-25 ^o C
• 7 days at 2-8 ^o C

4.5 mL PST Blood (Preferred)

0.5 mL Paediatric Micro-PST Blood (Preferred)

5 mL Adult Heparin Blood

4 mL Adult Plain Blood

3.5 mL SST Blood

0.5 mL Paediatric Microsample Blood

0.5 mL Paediatric Micro-heparin Blood
Reference Intervals

Units: umol/L

Reference ranges:

0 - 2 months	29 - 54
2 mths - 1 year	36 - 75
1 - 3 years	38 - 76
3 - 10 years	40 - 78
10 - 18 years	50 - 81
Adult	45 - 75

Uncertainty of Measurement: 20%

This test is routinely performed on all requests for serum iron, subject to sufficient specimen being available. The total iron binding capacity is the sum of the measured unbound iron binding capacity (not reported) and the serum iron (which is bound).

Equivalent transferrin concentration:

TIBC (umol/L) / 22 = transferrin (g/L)

Transferrin (g/L) x 22 = TIBC (umol/L)

Turnaround Time: Within 3 hours
Diagnostic Use and Interpretation

Transferrin accounts for over 95% of the iron-binding capacity of plasma. For clinical purposes TIBC is equivalent to measuring transferrin.

It is usually performed in conjunction with serum iron measurement, with iron saturation being calculated from these results.

TIBC is increased in iron deficiency, pregnancy, oral contraceptive use, and acute hepatitis.

TIBC is decreased in anaemia of chronic disease, chronic infections, haemochromatosis or iron overload from any cause, cirrhosis, protein deficiency and acute liver disease.

Recent intravenous iron infusion (such as ferric carboxymaltose) increases the measured iron binding capacity of a sample. While not a laboratory error, it is not reflective of the patient's iron stores/handling and may be clinically misleading. The half-life of ferric carboxymaltose is about 12hrs, however given the large iron load with a single dose it would not be recommended to repeat iron studies for at least 10 days without clear indication.

Caution: measurement of TIBC is unreliable in acute iron toxicity and desferrioxamine treatment.

See also:

• Ferritin
• Iron - serum/plasma
• Iron Saturation
• Soluble Transferrin Receptors
• Iron - Liver
• Haemoglobinopathy Screen
• Thalassaemia - Molecular Studies
• Haemochromatosis - Molecular Studies

Reference(s):

1. Geisser P. and Burckhardt S., The pharmacokinetics and pharmacodynamics of iron preparations . Pharmaceutics. 2011, 3, 12-33.

Contact Information

Emails to chemicalpathologist@adhb.govt.nz will receive priority attention from the on-call chemical pathologist.

If the query concerns a specific patient please include the NHI number in your email.

If email is not a suitable option, please contact the on-call chemical pathologist via Lablink (Auckland City Hospital ext. 22000 or 09-3078995).

Individual chemical pathologists may be contacted but will not be available at all times.

After-hours : contact Lablink (Auckland City Hospital ext. 22000 or 09-3078995) or hospital operator for on duty staff after hours.

Dr Samarina Musaad (Clinical Lead) : SamarinaM@adhb.govt.nz ext. 22402

Dr Cam Kyle: CampbellK@adhb.govt.nz ext 22052

Dr Weldon Chiu: WeldonC@adhb.govt.nz ext. 23427

Dr Campbell Heron: CHeron@adhb.govt.nz ext. 23427

Dr Sakunthala Jayasinghe: Sakunthala@adhb.govt.nz ext. 23427

Last updated at 15:26:00 06/01/2025