INTRODUCTION:
- Typhoid fever is the result of systemic infection mainly by salmonella typhi found in only humans.
- The disease is clinically characterized by a typical continuous fever for 3 to 4 weeks, relative bradicardia with involvement of lymphoid tissues and considerable constitutional symptoms.
- The term “enteric fever” includes both typhoid ad paratyphoid fevers.
- Typhoid fever is endemic in India.
- Reported data for the year 2013 shows 1.53 million cases and 361 deaths.
- The factors which influence the onset of typhoid fever in man are the infecting dose and virulence of the organism.
- Man is the only known reservoir of infection, viz., cases and carriers.
- The primary source of infection are faeces and urine of cases or carriers, the secondary sources are contaminated water, food, fingers and flies.
- There is no evidence that typhoid bacilli are excreted in sputum or milk.
CAUSES:
- Typhoid fever is contracted by drinking or eating the bacteria in contaminated food or water.
- People with acute illness can contaminate the surrounding water supply through stool, which contains a high concentration of the bacteria.
- About 3%-5% of people become carriers of the bacteria after the acute illness. Others suffer a very mild illness that goes unrecognized.
- These people may become long-term carriers of the bacteria even though they have no symptoms and be the source of new outbreaks of typhoid fever for many years.
SIGNS AND SYMPTOMS:
- High fever
- Diarrhea
- Rose spots
- Aches and pains
- Poor appetite
- Lethargy
MODE OF SPREAD:
- Typhoid fever is transmitted via the faecal- oral route or urine- oral route.
- This may take place directly through soiled hands contaminated with faeces or urine of cases or carriers, or indirectly by the ingestion of contaminated water, milk and/or food or through flies.
INCUBATION PERIOD:
- Usually 10-14 days. But it may be as short as 3 days or as long as 3 weeksdepending upon the dose of the bacilli ingested.
CLINICAL FEATURES:
- FIRST WEEK: malaise, headache, cough and sore throat in prodromal stage. The disease classically presents with step- ladder fashion rise in temperature over 4 to 5 days., accompanied by headache, vague abdominal pain and constipation or pea soup diarrhea.
- SECOND WEEK: between the 7 – 10 days of illness, mild hepatoslenomegaly occurs in majority of the patients. Relative bradycardia may occur and rose spots may be seen.
- THIRD WEEK: the patient will appear in the typhoid state, which is a state of prolonged apaty, toxemia, delirium, disorientation and/or coma. Diarrhea will then become apparent. If left untreated by this time, there is a risk( 5-10%) of intestinal hemorrhage and perforation.
PATHOPHYSIOLOGY:
Ingestion of contaminated food/ water
Carried by white blood cells in the liver, spleen and bone marrow
Multiply and reenter the bloodstream
Bacteria invade the gallbladder, biliary system and the lymphatic tissue of the bowel and multiply in higher number.
Then pass into the intestinal tract and can be identified for diagnosis in cultures from the stool tested in the laboratory.
LAB INVESTIGATIONS:
- Blood culture.
- Specific serologic test:
- Identify salmonella antibodies/ antigens
- Widal test and ELISA.
- Urine and stool culture.
- Marrow culture*: 90% sensitive unless until after the commencement of the antibiotics.
- Punch – biopsy samples of rose spots culture: 63% sensitive.
- Clot culture.
TREATMENT:
- SUPPORTIVE CARE: – maintenance of adequate hydration.
– Appropriate nutrition
- SPECIFIC CARE: – Antibiotics
- Corticosteroids
- Antipyretics
- ANTIBIOTICS like chloramphenicol(200mg,QID), ampicillin(750mg, QID), Co- trimaxazole( 2 tablets/ IV BDS), fluroquinolones like ciprofloxacin(500mg BDS).
- Incase of quinolone resistance – Azithromycin(500mg/ OD) and third generation cephalosporins like ceftriaxone( alternative).
- The treatment should be continued for 14 days.
PREVENTION:
- Regular hand wash.
- Drinking boiled water.
- Cleaning fruits and vegetables before their use.
- Get vaccinated.
RED FLAGS:
Sudden onset severe abdominal pain with garding and rigidity.
PITFALLS:
Other infection peptic ulcer with perforation.
PEARLS:
To avoid outside food intake &contaminated food intake.