ARUP's Laboratory Test Directory

0050779: Diphtheria, Tetanus, and H. Influenzae b Antibodies, IgG

Test Mnemonic: DTH
Methodology: Multi-Analyte Fluorescent Detection

Performed: Mon, Wed, Fri

Reported: 1-4 days

Specimen Required:  
Collect: One 4 mL SST.

Transport: 1.5 mL serum at 2-8°C. (Min: 0.7 mL)  Submit specimen in an ARUP Standard Transport Tube.

Pediatric Collection/Transport: 0.45 mL serum at 2-8°C.

Remarks: Acute and convalescent specimens must be labeled as such; parallel testing is preferred and convalescent specimens must be received within 30 days from receipt of the acute specimens. PLEASE CLEARLY MARK SPECIMENS "PRE-VACCINE" OR "POST-VACCINE" SO THAT SPECIMENS WILL BE SAVED AND TESTED SIMULTANEOUSLY.

Unacceptable Conditions: Plasma and other body fluids.  Severely lipemic, contaminated, or hemolyzed specimens.

Stability: After separation from cells: Ambient: 2 days; Refrigerated: 2 weeks; Frozen: 1 year (avoid repeated freeze/thaw cycles)

Reference Interval:
Diphtheria and tetanus:
Antibody concentration of  > 0.1 IU/mL is usually considered protective for diphtheria or tetanus.

Haemophilus influenzae type B:
< 1.0 µg/mL = Antibody concentration not protective.
> 1.0 µg/mL = Antibody to H. influenzae type B detected.  Suggestive of protection.

Interpretive Data:
Responder status is determined according to the ratio of a one-month, post-vaccination sample to pre-vaccination concentration of IgG antibodies as follows:

Diphtheria and tetanus:
1.  If the post-vaccination concentration is less than 1.0 IU/mL, the patient is considered a nonresponder.
2.  If the post-vaccination concentration is greater than or equal to 1.0 IU/mL, a patient with a ratio of less than 1.5 is a nonresponder, and a ratio of 1.5 to less than 3.0 is a weak responder, and a ratio of 3.0 or greater is a good responder.
3.  If the pre-vaccination concentration is greater than 1.0 IU/mL, it may be difficult to assess the response based on a ratio alone.  A post-vaccination concentration above 2.5 IU in this case is usually adequate.

Haemophilus influenza B:
1.  If the post-vaccination concentration is < 3.0 µg/mL, the patient is considered to be a nonresponder.
2.  If the post-vaccination concentration is 3.0 µg/mL, a patient with a ratio of 4 is a good responder, a ratio of 2-4 is weak responder, and a ratio of < 2 is considered a nonresponder.



CPT Code(s):
86317 Diphtheria; 86317 Tetanus; 86317 H. influenzae