How do you interpret widal test results for typhoid fever?

Answer 1

Widal test is an agglutination test for the detection of agglutinins (antibodies) for H and O antigen for salmonella in patients with enteric fever. Procedure: Serial dilutions of the patients serum is taken from 1:10 to 1:640. To each equal volumes of Salmonella antigens are added. The tubes are incubated overnight and read. Result: The highest dilution of the patients serum in which agglutinations occurs is noted, ex. if the dilution is 1 in 160 then the titer is 169. A single test of O titer of 1:100 or more and of H titer of 1:200 or more is significant. A rising titer of four fold or higher in an interval of 7 - 10 days is more meaningful than one test. Cautionary factors: In endemic areas, low titer of agglutinins is present in the serum of normal persons. Immunisation with TAB vaccine will show high titres of antibodies to S. typhi, S. paratyphi A and B. (in an infection there will be rise in only one type of antibodies) Person who have had past enteric infections or immunisations may develop anamestic reaction during unreleated fever like malaria. There is only a transient rise. Bacterial antigens used may contain fimbrial antigens which give false positive results. Cases treated early with chloramphenicol show poor antibody response. Test maybe positive in carriers

Answer 2

To,Th,Tah,Tbh, upto 1:80.

moreover significance of this test is to check the rising titre.

Answer 3

simple if negative take small dose of Cefoxine based medicines for 1 week to 2 weeks and do not forget to orange or sweet lime juice for the above period..... hahahahahaha

Answer 4

Isolated rise in Widal test reading is of little clinical significance. The rise in titre in two tests, taken apart by one week, in febrile illness points towards typhoid fever.