Dear Doctor,

I went to a clinic and was diagnosed with typhoid. But on visiting a bigger hospital, several tests revealed that my kidney was just working hard to get rid of toxins, hence the cause of the stomach pain I used to feel. I am now taking medication to heal the pain, what is the cause of the difference in diagnosis, Isabella.

Dear Isabella,

Besides the abdominal pain, what other symptoms did you mention onconsulting the clinic?

Typhoid is an infection of the intestines caused by coliform bacteria called salmonella typhi. The mode of entry is through fecal-oral route. On contacting typhoid it simply means, that in one way or the other, you ate food contaminated with fecal matter. Naturally, these micro organisms are passed in stool of an infected person. Such infections also result from poor cleanliness of food during cooking or serving. Poor hand hygiene when eating food is also another source of contamination. On contracting typhoid, the sickness manifests as high persistent fever with abdominal pain, nausea, vomiting, and enlarged spleen, but may not be limited to these symptoms.

Survival chances may be high but in severe cases, one can die due to intestinal perforation.

There are subclinical cases, where a person can be infected with low dose of germs, remains healthy, yet passes the microbe in stool thus infecting other susceptible people. The test commonly used over decades for diagnosing typhoid has been the Widal test where a positive result shows high antibody reaction towards antigens of the microbe. One of these 3 antigens (O) only suggests recent infection by salmonella typhi. However, accuracy of this test is higher when sample is taken after 10 days of fever. This test also generates false positive results hence no longer considered specific for diagnosis of typhoid.

Blood culture is the definitive test for diagnosis of typhoid. Here a sample of blood is inoculated in a culture medium such as MacConkey agar where microbes

become objectively visible, if the fever is as a result of typhoid. Accuracy of culture can also be improved when samples are taken before taking any antibiotics that is the reason why medics always discourage auto medication before diagnosis. In the likely event that it is not typhoid, abdominal pain can be a result of simple indigestion, constipation, or any other infection like by protozoa, worms. Some times being allergic to some food substances can also manifest as abdominal pain. Ultimately, the difference in tests or diagnosis could be due to wrong timing of test done or false positive results.

Dr Rachna Pande  is a specialist in internal medicine at Ruhengeri Hospital