View
2.593
Download
1
Category
Tags:
Preview:
DESCRIPTION
Citation preview
TYPHOID FEVER
Definition of Typhoid fever
Acute enteric infectious disease
caused by Salmonella typhi (S.Typhi).
prolonged fever, Relative bradycardia,
apathetic facial expressions, roseola,
splenomegaly, hepatomegaly, leukopenia.
intestinal perforation, intestinal
hemorrhage
Etiology
Serotype: D group of Salmonella
Gram-negative rod non-spore flagella Culture characteristics
Antigens: located in the cell
capsule
H (flagellar antigen).
O (Somatic or cell wall antigen).
Vi (polysaccharide virulence)
“widel test”
A schematic diagram of a single A schematic diagram of a single Salmonella typhi Salmonella typhi cell showing the locations of the H (flagellar), 0 cell showing the locations of the H (flagellar), 0 (somatic), and Vi (K envelope) antigens.(somatic), and Vi (K envelope) antigens.
Endotoxin
A variety of plasmids
Resistance: Live 2-3 weeks in
water. 1-2 months in stool. Die
out quickly in summer
Resistance to drying and
cooling
Epidemiology
continues to be a global health problem
areas with a high incidence include Asia, Africa and Latin America
affects about 6000000 people with more than 600000 deaths a year. 80% in Asia .
sporadic occur usually, sometimes have epidemic outbreaks.
Transmission
fecal-oral route
close contact with patients or
carriers
contaminated water and food
flies and cockroaches.
Susceptibility and immunity
all people equally susceptible to infection
acquired immunity can keep longer, reinfection are rare
immunity is not associated with antibody level of “H”, “O”and “VI”.
No cross immunity between typhoid and paratyphoid
All seasons, usually in summer and autumn.
Most cases in school-age children and young adults.
both sexes equally susceptible
Major findings in lower ileum
Hyperplasia stage(1st week): swelling lymphoid tissue and
proliferation of macrophages. Necrosis stage(2nd week): necrosis of swelling lymph nodes or
solitary follicles. Ulceration stage(3rd week): shedding of necrosis tissue and
formation of ulcer ----- intestinal hemorrhage, perforation .
Stage of healing (from 4th week): healing of ulcer, no cicatrices and
Clinical manifestations
Incubation period: 3 ~ 60 days(7 ~ 14).
The initial period (early stage) First week. Insidious onset. Fever up to 39~400C in 5~7 days chills 、 ailment 、 tired 、 sore
throat 、 cough ,abdominal discomfort and constipation et al.
The fastigium stage
second and third weeks. Sustained high fever 、 partly remittent
fever or irregular fever. Last 10 ~ 14 days.
Gastro-intestinal symptoms: anorexia 、 abdominal distension or pain 、diarrhea or constipation
Neuropsychiatric manifestations: confusion 、 blunt respond even delirium and coma or meningism
Circulation system:
relative bradycardia or dicrotic pulse.
splenomegaly 、 hepatomegaly
toxic hepatitis.
roseola :30%, maculopapular rash
a faint pale color, slightly raised
round or lenticular, fade on pressure
2-4 mm in diameter, less than 10 in number
on the trunk, disappear in 2-3 days.
fatal complications:
intestinal hemorrhage
intestinal perforation severe toxemia
Diagnosis
Epidemiology data
Typical symptoms and signs
Laboratory findings.
TREATMENT
General treatment
isolation and rest
good nursing care and supportive treatment
close observation T,P,R,BP,abdominal condition and stool .
suitable diet include easy digested food or half-liquid food.drink more water
intravenous injection to maintain water and acid-base and electrolyte balance
Symptomatic treatment:
for high fever: physical measures firstly
antipyretic drugs such as aspirin should
be administrated with caution
delirium,coma or shock,2-4mg
dexamethasone in addition to antibiotics
reduces mortality.
Etiologic and special treatment
1.Quinolones:
first choice
it’s highly against S.typhi
penetrate well into macrophages,and achieve
high concentrations in the bowel and bile lumens
Norfloxacin (0.1 ~ 0.2 tid ~ qid/10 ~ 14 days).
Ofloxacin (0.2 tid 10 ~ 14days).
ciprofloxacin (0.25 tid)
caution: not in children and pregnant
2.Chloramphenicol:
For cases without multiresistant S.typhi.
Children in dose of 50 ~ 60mg/kg/per day.
adult 1.5 ~ 2g/day. tid.
Unable to take oral medication, the same dosage
given introvenously
after defervescence reduced to a half. complete a
10 ~ 14 day course.
But ,drug resistance, a high relapse rate,bone
marrow toxicity.
3.Cephalosporines: Only third generation effective
Cefoperazone and Ceftazidime.
2 ~ 4g/day .10~14 days.
4.Treatment of complication. Intestinal bleeding:
bed rest, stop diet,close observation T,P,R,BP.
intravenous saline and blood transfusion,and attention to acid-base balances.
sometimes,operative.
Perforation:
early diagnosis.
stop diet.
decrease down the stomach pressure.
intravenous injection to maintain
electrolyte and acid-base balances.
use of antibiotics.
sometimes operative.
Toxic myocarditis:
bed rest, cardiac muscle protection drugs,
dexamethasone, digoxin.
5.Chronic carrier: Ofloxacin 0.2 bid or ciprofloxacin 0.5 bid, 4 ~ 6
weeks. Ampicillin 3 ~ 6g/day tid plus probenecid 1 ~
1.5g/day. 4 ~ 6 weeks. TMP+SMZ
2 tabs. Bid. 1 ~ 3 months. Cholecystitis may require cholecystectomy.
Recommended