Is Widal test a confirmation of typhoid?
Q: I am a 38 years old male, who had severe weakness, dizziness, breathlessness and chest pain for over period of one month last year. It started with a throat infection. Finally, I underwent Widal test, where my paratyphi B was found to be 1:160 and white blood cell (WBC) count was 3500. Based on this, I was treated for typhoid. But I never had fever in this period. I also underwent ECG and 2D echo cardiogram, which came normal. However, I was diagnosed with GERD. Two months back, I again went for Widal test, where my paratyphi B was found to be 1:20 and white blood cell (WBC) count was 6300. Now, I am again experiencing fatigue and chest pain. Widal test has revealed Typhi O as 1:80 and Typhi H 1:160. WBC came 4300. Is Widal test a confirmation of typhoid? I have no loose motions, fever and do exercise regularly.
A:Widal test is a serological test for typhoid. Blood sample is withdrawn and serum is mixed with the sera containing typhoid antibodies, which has been prepared from patients of typhoid. If there is agglutination reaction, the test is considered positive. It is expressed in titres and a titre of 1:160 or above would be significant. Ideally, the test has to be done for the first time around 5th to 7th day of illness and then repeated after 1-2 weeks to see the rising titres. It is not a 100% confirmatory test for typhoid as the titres maybe high in certain areas depending on the endemicity of typhoid there. Also, we may see a positive test due to past immunisation, previous infection, infection with other gram negative bacteria, malaria etc. The gold standard for diagnosis is isolation of salmonella bacteria by culture from blood/urine or stool. In absence of fever or other symptoms, widal alone would not suffice to diagnose typhoid in your case.