Febrile agglutinin tests are performed concurrently with blood culture for microorganism identification to diagnose the infectious cause of a febrile condition. The test is performed with the use of antigens to specific organisms and their reaction (agglutination) with antibodies in the client's blood serum. Diseases that can be diagnosed using these tests, along with the type of febrile agglutinin test used, are listed in Table 3-11.
The cold agglutinin test is performed to identify cold agglutinins, antibodies that result from Mycoplasma pneumoniae infection. This infection is caused by a nonbacterial agent, but it still manifests a febrile condition. The antibodies cause agglutination of red blood cells at temperature ranges of 35.6 to 46.4°F (2 to 8°C), with a positive titer resulting in those with atypical pneumonia or cold agglutination disorders, depending on the severity of the disease.
| Weil-Felix reaction (Proteus antigen test) | <1:80 |
| Widal's test (O and H antigen tests) | <1:160 |
| Brucella agglutination test (slide agglutination test) | <1:80 |
| Tularemia agglutination test (tube dilution test) | <1:40 |
| M. pneumoniae (cold agglutinin test) | <1:32 |
Nursing Care Before the Procedure
Client preparation is the same as that for any study involving the collection of a peripheral blood sample (see Appendix I).
A venipuncture is performed and the sample collected in a red-topped tube. The sample must be handled gently to avoid hemolysis and transported immediately to the laboratory.
Nursing Care After the Procedure
Care and assessment after the procedure are the same as for any study involving the collection of a peripheral blood sample.