Hyderabad doctors warn Widal test may cause typhoid misdiagnosis amid viral fever surge
Doctors in Hyderabad are warning against the routine use of Widal tests amid a surge in viral fevers, saying the test can produce misleading results. They caution that unnecessary testing and treatment may cause anxiety and encourage indiscriminate antibiotic use.
Hyderabad: Walk into almost any clinic with a fever, and chances are you will leave with a lab report declaring you positive for typhoid.
As cases of viral fevers surge during the ongoing season, doctors warn patients that they are being routinely misdiagnosed due to a heavy reliance on Widal test, an antiquated 130-year-old diagnostic tool that is frequently setting off false alarms.
Typhoid is endemic in Hyderabad, and a majority of people already carry immunity in their blood. When ordinary viral fevers hit, the Widal test gets confused and flashes positive, fueling a wave of unnecessary panic and the indiscriminate use of heavy broad-spectrum antibiotics.
While the Widal test has its limitations, there is no denying the fact that a large number of care givers also indulge in prescribing this unnecessary test. There is also a problem of unqualified individuals (quacks) at neighborhood clinics and outskirts, who frequently order such diagnostics to vulnerable patients.
“Before prescribing a Widal test, experienced physicians do a lot of background work in understanding the source of infection, which is contaminated drinking water. We have come across a number of instances where quacks blindly prescribe Widal tests, which invariably come as false positives,” says senior pediatrician from Hyderabad, Dr Madapa Karuna.
Dr. Musa Khan, Superintendent of the Fever Hospital, highlights another major flaw in how commercial diagnostic centers and even care givers handle the test is failing to account for regional baseline immunity.
“There is no denying the fact that the Widal test gives false positives a lot and need to be prescribed carefully. We usually opt for cell culture for confirmation of typhoid. Widal tests also tend to differ from area to area and a reading normal in Banjara Hills will not hold the same in Nallakunta,” he says.
Since typhoid bacteria is abundant in vulnerable municipal water systems, a large percentage of healthy people do have antibodies. A lab applying a standard cutoff without taking into account the local antibodies level can turn healthy citizens into instant patients, doctors added.
Dr. Khan also pointed out that doctors do not have the luxury to wait for days for cell culture results to arrive, if a patient walks-in with high temperature. “People should also keep in mind that conducting such tests takes time, like days, and usually doctors do not take chances of waiting for the results. They prescribe medicines covering a bouquet of ailments so that the patient immediately gets relief”.
