Alternative name: (Also known as functional antibodies)

The terms “Functional or Specific antibodies” refer to tests for the measurement of IgG antibody levels to Tetanus/Haemophilus influenzae b and Pneumococcal polysaccharide used in order to define the efficiency of the the antibody response in immunocompromised individuals.Measurement of specific antibody production (spontaneous and post immunisation) is useful in the assessment of patients with suspected immune (immunoglobulin) deficiency (hereditary or acquired).

The pneumococcal antibody test is of limited use in testing for specific immunisation status since the new vaccines contain very different serotypes.

Indication: Investigating humoral immune deficiency associated with (SPUR) severe, protracted, recurrent unusual or recurrent infection – particularly URTI, LRTI. Also response to vaccination in immuno- compromised e.g splenectomy, patients. A widely misused test – not to be used as general test of vaccination and certainly not as a test of infection.
Interpretation: Tetanus toxoid – a test of immunolgical memory upon vaccination.
Pneumococcal polysaccharide (Pneumovax) – a test of responses to polyscacharide antigens
Haemnophilusb (protein polysaccharide) – used as a test of response to protein vaccine. Vaccination history must be known

  • If responses are poor repeat vaccination and reevaluate.
  • Never use live vaccines suspect patients.
Sample: Serum Separator Tube (SST)
Assay details: ELISA
Restrictions: Referred test
Reference range: Haemophilus b: <0.1ug/ml
Pneumococcal polysaccharide (Pneumovax): <10ug/ml
Tetanus toxoid: <0.01ug/ml
Assay range notes: Equivocal
Hib: 0.1-1.0ug/ml
PCP: 10-30ug/ml
Tet: 0.01-0.15ug/ml
Hib: > 1.0ug/mlPCP: > 30ug/mlTet: > 0.15ug/ml
Turnaround time: 28 Days
Analysing laboratory: North Cumbria