Typhoid Fever in Children

Typhoid fever is an acute generalized infection of the reticuloendothelial, intestinal lymphoid tissue and gall bladder caused  by salmonella typhi.

Epidemiology

As per the WHO estimates, there were 20 million cases of Typhoid fever globally with 20 lakh deaths in the year 2000. Among them Asia and Africa account for 70.80% of cases.

Reservoir  

Humans are the sole reservoir of salmonella typhi 3.5% of patient become chronic carriers after a clinical or sub clinical infection with typhoid and is because persistence of typhoid bacilli in gall bladder and biliary tract middle aged females are most likely to become carriers. It is rare to develop a carrier state befor the age of 20 years.

Incubation period

The usual incubation period is 10 to 14 days but it may very from 3 to 60 days.

Causative Agent

Salmonella Typhi, a gram negative beacilli which are motile, non acid fast, non capsulated and non sporing flagellate, facultative anerobes.

Host

Human beings are the only known host at percent that are susceptible to salmonella typhi infection. The peak incidence is in 5 to 15 years of age but cases have been reported frequently in infant and toddlers especially in developing countries.

Mode of Transmission

Typhoid is food and water borne disease. House flies are notorious of spreading the infection via food, over crowding, poor personal hygiene, poverty, open defecation and parasitic infestation are important predisposing factor in neonates, the infection are transmitted vertically from mother.

Clinical Presentation

Typhoid  Fever exhibits a wide range of clinical severity like malaise, decrease appetite and body ache, constipation in older children and adult where as  diarrhea may occou in younger children . A coated tongue tender abdomen, anemia, hepato splenomegaly are invariably present menigismus, delirium, stupor and convulsion may occur.

Complications

The commonest Complications related to the Gastro Intistinal  tract and paralytic ileus with abdominal distension is the most frequent manifestation 10 to 20 % of patient have occult blood in stool 0.5 to 3% patients may develop intestinal perforation, followed by peritonitis. DIC,HUS, Hepatitis, glomerulonephiritis, splenic and liver abscess, nephritic syndrome, endocarditic corneal ulcer, vitreous hemorrhage.

Laboratory diagnosis

• Hematological:  anemia may be present. Total leucocyte count may be normal or leucopaenia is seen in 20 to 25% cases. Relative lymphopenia may be seen. Thrombocytopenia may occur in 10 to 15% cases.
• Biochemical: Serum bilirubin ,SGOT and SGPT may be elevated mildly in infant and younger children. Prothrombin time and APTT are also mildly prolonged.

Culture:
Blood culture is the main way of diagnosis. Bone marrow aspiration culture is the gold standard for definitive diagnosis particularly for patient who have already received antibiotics, have 1 mg history of illness like P.U.O and negative blood culture.
Stool culture: Stool culture are positive in 30% cases but during 2^nd and week
Urine Culture: Not recommended because of poor sensitivity.

Serological Test:

Widel test: this is the most widely used  serological test that major measures agglutinating antibody levels against ‘O’ and ‘H’ antigen.

Management:

Prompt management of typhoid can reduce the morbidity and mortality to a great extent 90% of cases can be safely treated on a domicailliry basis.

Commonly used antibiotics are:

1.     Cefixime

2.     Inj. Ceftrixone

3.     Ciprofloxacin, Ofloxacin

4.     Azithromycin

5.     Imipenam

Duration of treatment:

Most of the children become afebrile within 7 days of treatment but treatment should be continued for at least 14 days.

Treatment of carrier:

Cholecystitis requires cholecystectomy

Prevention:

1.     To provide safe drinking water

2.     To maintain personal hygiene

3.     Vaccines

4.     Health education