Diphtheria

Question 1

Diphtheria

Answer 1

Acute toxin-mediated disease caused by Corynebacterium diphtheria,
Gram-positive aerobic bacillus.

Question 2

Pathogenesis

Answer 2

the major virulence factor of C. diphtheria is an exotoxin

encoded on a lysogenized bacteriophage

Question 3

Local and systemic effects of diphtheria

Answer 3

1. Local effects: 
• Membrane formation in throat. 
2. Systemic effects
• Myocarditis 
• Neuropathy

Question 4

Transmission

Answer 4

from person to person, usually through respiratory droplets, like from coughing or sneezing

Question 5

Clinical manifestations

Answer 5

symptoms usually start 2 to 5 days after becoming infected. The main
symptoms of diphtheria are:
• typically involves pharynx and tonsils, leathery adherent
membrane, which can cause respiratory obstruction
THICK GREY MEMBRANE
• a high temperature (fever) of 38C or above
• feeling sick
• sore throat
• headache
• swollen glands in your neck BULLNECK APPEARANCE
• difficulty breathing and swallowing

Bull throat neck + sore throat = SUSPECT

Question 6

Diagnosis

Answer 6

1. clinical diagnosis: signs and symptoms predicting
   diphtheria 2. laboratory diagnosis: isolation of C. diphtheriae by culture and positive Elek Test - or- PCR for tox gene

Question 7

Management (Patients with respiratory diphtheria)

Answer 7

1. Hospitalization, close monitoring and respiratory isolation
2. Antitoxin should be given as soon as the diagnosis is
   seriously suspected 3. Antibiotic treatment with erythromycin 4. Patients should be immunized during the recovery
   phase..why? (the infection does not always induce adequate antibody respond against toxin).

Question 8

Prevention

Answer 8

• Routine childhood vaccination (+ adult boosters)
• Close contacts should also receive antibiotics
• If the diphtheria immunizations of a close contact are not up-
to-date, a diphtheria toxoid booster, appropriate for age, should be given.