Key Points in Diagnosing Typhoid

Typhoid Fever is an acute infection or disease which is systemic arising from Salmonella Typhi or Paratyphi. The disease is known to man only and affects a great number of population worldwide especially in the developing countries.

The manifestation of the signs and symptoms of typhoid fever are very similar to quite a number of other infectious diseases and that makes typhoid a true diagnostic challenge. Among the classical clinical presentation of typhoid include fever, malaise, diffuse abdominal pain and constipation.

The diagnostic difficulty of typhoid makes clinicians to sometimes mistake typhoid for another similarly presenting infection and leave the typhoid untreated in the patient. An untreated typhoid may quickly progress to delirium (typhoid psychosis), intestinal haemorrhage, bowel perforation and death within one month of onset. Survivors may be left with long term or permanent neuropsychiatric complications. Understanding the classical clinical features of typhoid can help in its quick diagnosis and treatment which can prevent the occurrence of such serious complications.

Quick Facts About Typhoid Fever 


  • Typhoid Fever affects only human beings.
  • The route of transmission is feco-oral (from infected faeces to the mouth) through several media.
  • There are two species of Salmonella which cause the disease : Salmonella Typhi and Salmonella Paratyphi (A, B and C).
  • High fever (fluctuating on temperature chart) is a common clinical presentation of typhoid which usually rises in the afternoon.
  • Prompt and appropriate antibiotic therapy renders typhoid fever a short-term febrile illness requiring a median of 6 days treatment.
  • Untreated typhoid is a life threatening illness of several weeks duration in the hospital and long-term morbidity often involving the central nervous system.
  • Most documented cases of typhoid involve school-age children and young adults. It is however thought to actually affect very young children and infant more which are mostly unrecognised undocumented.
  • Typhoid Fever has no racial predilection. It affects people of all races all around the world.
  • Typhoid seems to slightly be more prevalent in males than females.
  • Typhoid prevention is possible by vaccination, better environmental sanitation and personal hygiene.



The course of untreated typhoid fever is divided into four distinct stages, each lasting for about one week. Over the course of these stages, the patient becomes exhausted and emaciated.

week 1 (First Stage) 

In the first week, the body temperature rises slowly and fever fluctuations are seen with relative bradycardia (Faget sign), malaise, headache, and cough. A bloody nose (epistaxis) is seen in 25% of cases and abdominal pains may also be present at this stage.

Lab investigations will show a decrease in the number of circulating white blood cells (leucopenia), and eosinophils (eosinopenia) and relative lymphocytosis. Blood cultures are positive for Salmonella typhi and paratyphi at this stage but widal test is usually negative in this first week.

Week 2 (Second Stage) 

In the second week of infection, the person often feels too tired to get up with a high fever of around 40 degrees Celsius and bradycardia. Delirium or typhoid psychosis is frequent in this stage, although often calm but can sometimes be agitated. This delirium is what gives typhoid the nick name of nervous fever. Rose spots also begin to appear on the lower chest and abdomen in about 35% of patients (especially light skinned patients). The abdomen is distended and painful in the right lower quadrant. Diarrhoea (in children) or constipation (in adults) may be present and there is liver and spleen enlargement (hepatosplenomegaly) and tenderness.

Lab investigations during the second week of infection will show elevated liver enzymes (transaminases) and widal test is strongly positive in both O and H titres. Blood culture of Salmonella may still be positive at this stage.

Week 3 (Third Stage) 

In the third week of untreated typhoid infection, a number of complications may occur which can include

  • Intestinal haemorrhage which is due to bleeding in the congested payer’s patches of small intestines.
  • Intestinal perforation in the distal ileum which is very fatal.
  • Encephalitis.
  • Respiratory diseases like pneumonia and acute bronchitis.
  • Neuropsychiatric symptoms.
  • Metastatic abscesses, cholecystitis, endocarditis and osteitis.
  • Dehydration which can lead to the patient becoming delirious (typhoid state).
  • Bleeding tendency due to low platelets levels.

Week 4 (Fourth Stage) 

During the fourth week, the fever begins to subside and patient may begin to recover although there may be a recurrence of the signs and symptoms again. Most patients will then become chronic carriers of typhoid and can cause infection of other individuals through unhygienic practices.