All About Diptheria

Causative Agent

  • The disease is caused by Corynebacterium diphtheriae.
  • They are normal symbionts in the throat, skin, and conjunctiva.
  • The other types of corynebacterium are C.ulcerans, C.minutissimum, and C.tenuis.

Resistance

  • The bacteria are destroyed by heat and antiseptics.
  • They are also resistant to light, freezing.

Pathogenicity

The common site of infection is the respiratory tract(fauces, larynx) occasionally occurs in conjunctival, genitovulval, vaginal, and skin. Faucial diphtheria is the common type.

Pathology

  • After infection, bacteria multiply on the mucous membrane or skin abrasion and start producing toxins. Hence this disease is called Toxemia. These toxins cause the destruction of epithelium and superficial inflammatory response. It causes three types of diseases:
  • Malignant or hypertoxic: Edema of the neck causes the Bull neck which causes circulatory failure and death of the patients.
  • Septic: In this type ulcers and cellulitis are seen.
  • Hemorrhagic: In this condition, bleeding is observed from the pseudomembrane edge.

Complications

  • Asphyxia: Tracheostomy may be done in emergency conditions.
  • Acute circulatory failure
  • Myocarditis
  • Postdiphtheritic paralysis
  • Septic: Pneumonia is seen in this condition.
  • Relapse.

Epidemiology

  • In endemic areas, it is a disease of childhood uncommon below 1st year and in peaks at 5.
  • It occurs in the respiratory tract, in the wounds, or in the skin of the infected person or carriers.
  • Transmission occurs by saliva droplets dissemination from cases or carriers, direct contact.
  • In healthy people, the strains of bacteria persist for life in nasopharyngeal or cutaneous regions.

Treatment

  • The antitoxin is given (but not for cutaneous diphtheria) to neutralize the circulating toxin. The recommended dosage is 20,000-1,00,000 units.
  • Penicillin or Erythromycin is the antibiotics that should be taken for 14 days.
  • Erythromycin is given for the treatment of carriers.
  • Complete bed rest and supportive therapy and treatment of complications.

Diet

  • The patient should take utmost care about their diets.
  • Fluid, semi-solid and soft foods should be taken.
  • Fluids include milk, fruit juices.
  • Alcohol, spicy, and oil foods are avoided.
  • Drink plenty of water.

Summary

  • The disease is caused by Corynebacterium diphtheriae.
  • They are normal symbionts in the throat, skin, and conjunctiva.
  • The bacteria are destroyed by heat and antiseptics.
  • The common site of infection is the respiratory tract(fauces, larynx) occasionally occurs in conjunctival, genitovulval, vaginal, and skin.
  • It causes three types of diseases:
  • Malignant or hypertoxic
  • Septic
  • Hemorrhagic
  • Asphyxia, Acute circulatory failure, Myocarditis, Postdiphtheritic paralysis, Relapse are the complications seen.
  • In endemic areas, it is a disease of childhood uncommon below 1st year and peaks at 5.
  • It occurs in the respiratory tract, in the wounds, or in the skin of the infected person or carriers.
  • Transmission occurs by saliva droplets dissemination from cases or carriers, direct contact.
  • Penicillin or Erythromycin is the antibiotics that should be taken for 14 days.
  • Fluid, semi-solid and soft foods should be taken.
  • Alcohol, spicy, and oil foods are avoided.
  • Drink plenty of water.