DIPHTHERIA
INTRODUCTION:
✓ First described in 5th century BC by Hippocrates.
✓ It is an acute infectious disease, either an upper respiratory tract infection or
a cutaneous infection.
✓ Usually occurs in spring or in winter months.
✓ Primarily a disease of childhood populations younger than 12 years.
✓ Susceptible to the disease at the age of 6 – 12 months.
✓ Advent of diphtheria vaccination – dramatic decline in pediatric population.
✓ Shifted to the adolescent and adult population, ages 40 years & older.
ETIOLOGY:
✓ Aerobic, non-motile, gram-positive, non-sporing, non-encapsulated bacteria,
Corynebacterium diphtheriae.
✓ It has 4 biotypes: mitis, intermedius, belfanti & gravis.
✓ Chinese letter configuration: Albert’s staining.
PATHOPHYSIOLOGY:
✓ Susceptible group: who aren’t completely immunized or have low antitoxin
antibody levels – exposed to a carrier or diseased individual.
✓ Carrier: whose cultures are positive for the diphtheria species – no signs and
symptoms.
✓ Communicable for 2 – 6 weeks without treatment.
✓ Risk factors – overcrowding, poor health, substandard living conditions,
incomplete immunization & immunocompromised states.
✓ Human carriers – main reservoir.
✓ Transmission:
• Via respiratory droplets, nasopharyngeal secretions.
• Cutaneous disease – contact with the wound exudates.
✓ Mechanism:
Adheres to mucosal epithelial cells – exotoxin released by
endosomes
Localized inflammatory reaction.
INTRODUCTION:
✓ First described in 5th century BC by Hippocrates.
✓ It is an acute infectious disease, either an upper respiratory tract infection or
a cutaneous infection.
✓ Usually occurs in spring or in winter months.
✓ Primarily a disease of childhood populations younger than 12 years.
✓ Susceptible to the disease at the age of 6 – 12 months.
✓ Advent of diphtheria vaccination – dramatic decline in pediatric population.
✓ Shifted to the adolescent and adult population, ages 40 years & older.
ETIOLOGY:
✓ Aerobic, non-motile, gram-positive, non-sporing, non-encapsulated bacteria,
Corynebacterium diphtheriae.
✓ It has 4 biotypes: mitis, intermedius, belfanti & gravis.
✓ Chinese letter configuration: Albert’s staining.
PATHOPHYSIOLOGY:
✓ Susceptible group: who aren’t completely immunized or have low antitoxin
antibody levels – exposed to a carrier or diseased individual.
✓ Carrier: whose cultures are positive for the diphtheria species – no signs and
symptoms.
✓ Communicable for 2 – 6 weeks without treatment.
✓ Risk factors – overcrowding, poor health, substandard living conditions,
incomplete immunization & immunocompromised states.
✓ Human carriers – main reservoir.
✓ Transmission:
• Via respiratory droplets, nasopharyngeal secretions.
• Cutaneous disease – contact with the wound exudates.
✓ Mechanism:
Adheres to mucosal epithelial cells – exotoxin released by
endosomes
Localized inflammatory reaction.
