Widal test
Noun: A serological blood test used to aid in the diagnosis of typhoid fever and other infections caused by Salmonella bacteria. The test detects the presence of agglutinating antibodies against the O (somatic) and H (flagellar) antigens of Salmonella typhi and Salmonella paratyphi.
The term is used as a singular noun to refer to the specific diagnostic procedure. It is often preceded by the definite or indefinite article (e.g., the Widal test, a Widal test).
- The doctor ordered a Widal test to confirm the suspected case of typhoid fever.
- The Widal test results showed a significant rise in antibody titers, supporting the diagnosis.
- In many laboratories, the Widal test has been supplemented or replaced by more specific methods.
- To perform/conduct/run a Widal test: This describes the action of carrying out the test.
- The laboratory technician will perform a Widal test on the serum sample.
- Widal test positive/negative/result: These are common collocations describing the outcome.
- A single Widal test positive result must be interpreted with caution due to possible cross-reactivity.
- Widal reaction: A synonymous term often used interchangeably with "Widal test," though it can specifically refer to the observed agglutination reaction.
- Typhoid serology: A broader category of diagnostic tests that includes the Widal test.
- Febrile agglutinins test: A similar, more general term for tests detecting antibodies that cause clumping (agglutination) in response to fever-causing bacteria, which includes the Widal test.
- Typhoid agglutination test
- Febrile agglutinins test (in the specific context of typhoid/paratyphoid fever)
The Widal test is named after Georges-Fernand Widal, the French physician who introduced it. Its primary clinical application is for the diagnosis of enteric fever (typhoid and paratyphoid). A key diagnostic principle is testing paired serum samples (acute and convalescent) to demonstrate a fourfold rise in antibody titer, which is more indicative of active infection than a single test result.
- a test for detecting typhoid fever and other salmonella infections