Test ID: TTIG
Tetanus Toxoid IgG Antibody Assay, Serum
Useful For
Suggests clinical disorders or settings where the test may be helpful
Assessment of an antibody response to tetanus toxoid vaccine
May be used to aid diagnosis of immunodeficiency
Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Tetanus is a nervous system disease characterized by severe muscle spasms caused by the toxin tetanospasmin that is produced by Clostridium tetani organisms. The disease is preventable by vaccination with tetanus toxoid (formaldehyde-treated tetanospasmin). Tetanus toxoid is an excellent immunogen; it stimulates development of antitetanus toxoid antibodies.
Subsequent to vaccination, a patient's immunological response may be assessed by determining the presence of tetanus toxoid antibody levels in the serum. An absence of antibody formation postvaccination may relate to immune deficiency disorders, either congenital, acquired, or iatrogenic due to immunosuppressive drugs.
Reference Values
Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
The minimum level of protective antibody in the normal population is between 0.01 and 0.15 IU/mL. The majority of vaccinated individuals should demonstrate protective levels of antibody >0.15 IU/mL.
Interpretation
Provides information to assist in interpretation of the test results
Results > or =0.16 IU/mL suggest a vaccine response.
Some cases of tetanus, usually mild, occasionally have been observed in patients who have a measurable serum level of 0.01 to 1.0 IU/mL.
Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
This test should not be used to diagnose tetanus infection. The diagnosis of tetanus is by clinical observation. A positive wound culture for the agent of tetanus, Clostridium tetani, may support, but does not confirm, the diagnosis. Toxin assays for tetanospasmin may be useful, but are only available in a few laboratories.
The results obtained from this assay are not diagnostic proof of lack of protection/protection against tetanus, or the presence/absence of immunodeficiency.
Supportive Data
Several studies were performed to determine minimum protective levels of tetanus toxoid antibody. The results suggest that minimal protective levels range from 0.01 IU/mL to 0.15 IU/mL, depending on the study. The largest of these studies conducted in the United States involved a sample population of 10,618 individuals, ranging from age 6 upwards. Overall, 69.7% had levels of >0.15 IU/mL: the rate decreased from 87.7% in 6 to 11 year olds to 27.8% in those 70 years of age and older. At Mayo, 100 normal donor sera were tested. Of these, 98% had antibody levels of >0.15 IU/mL, and 100% had levels of >0.01 IU/mL.
Clinical Reference
Provides recommendations for further in-depth reading of a clinical nature
1. Bleck TP: Clostridium tetani (tetanus). In Principals and Practice of Infectious Disease. 5th edition. Edited by GL Mandell, JE Bennett, R Dolin. Churchill Livingstone, Philadelphia, 2000, pp 2537-2543
2. Gergen PJ, McQuillan GM, Kiely M, et al: A population-based serologic survey of immunity to tetanus in the United States. N Engl J Med 1995;332:761-766
3. Bjorkholm B, Wahl M, Granstrom M, Hagberg L: Immune status and booster effects of low doses of tetanus toxoid in Swedish medical personnel. Scand J Infect Dis 1994;26:471-475
4. Ramsay ME, Corbel MJ, Redhead K, et al: Persistence of antibody after accelerated immunization with diptheria/tetanus/pertussis vaccine. Br Med J 1991;302:1489-1491
5. Rubin RL, Tang FL, Chan EK, et al: IgG subclasses of autoantibodies in systemic lupus erythematosus. Sjogren's syndrome, and drug-induced autoimmunitiy. J Immunol 1986;137:2522-2527
6. Simonsen O, Bentzon MW, Heron I: ELISA for the routine determination of antitoxic immunity to tetanus. J Biol Stand 1986;14:231-239


