I. Clinical Features of Diphtheria
1. Clinical manifestations
- Inflammation of the throat, nose, and larynx
- Red throat, painful swallowing
- Bluish skin, fatigue, swelling of lymph nodes under the jaw causing neck swelling
- Presence of grayish or whitish pseudomembrane tightly adhered to the inflamed tissue, which may bleed when removed.
2. Transmission mechanism
- Incubation period: 2 weeks
- Direct or indirect transmission via respiratory droplets
- Contact with contaminated items such as toys or objects with secretions from infected individuals
3. Dangerous complications
- Myocarditis, with a poor prognosis and high mortality rate
- Neurological complications leading to paralysis of the eye muscles, facial muscles, or respiratory muscles
- Conjunctivitis
- Respiratory failure due to airway obstruction, particularly in children, especially infants
II. Treatment Approaches for Diphtheria
1. Antitoxin therapy with Diphtheria Antitoxin Serum (DAS):
DAS is prepared from horse serum and contains proteins foreign to the human body. Before administration, it must be tested on the conjunctiva or injected into the skin. Epinephrine should be readily available to counteract any allergic reactions. Due to current lower purity of DAS, it is often administered intramuscularly or subcutaneously.
Dosage of antitoxin depends on the clinical severity and the time elapsed since onset of symptoms:
- Localized skin lesions: 20,000 - 40,000 units
- Nasopharyngeal diphtheria < 48 hours: 20,000 - 40,000 units
- Pharyngeal and laryngeal diphtheria: 40,000 - 60,000 units
- Disseminated disease > 72 hours from diagnosis: 80,000 - 100,000 units
- Malignant diphtheria with "bull neck" appearance: 80,000 - 100,000 units
2. Antibiotic therapy to eradicate bacteria:
Antibiotics cannot substitute antitoxin therapy but are crucial to halt further toxin production:
Only Penicillin and Erythromycin are recommended:
- Erythromycin orally at 40 - 50 mg/kg/day, maximum 2 g/day.
- Penicillin G intramuscularly or intravenously at 100,000 - 150,000 units/kg/day divided into 4 doses, or Procaine Penicillin intramuscularly at 25,000 - 50,000 units/kg/day divided into 2 doses.
- Treatment duration: 14 days.
Supportive therapy:
- Bed rest, electrolyte solution, airway management, and Prednisone. Prednisolone is contraindicated if the patient exhibits myocarditis complications.
- Immunization is essential post-recovery, as half of the cases do not develop immunity against diphtheria and remain at risk of reinfection.
III. Prevention Measures for Diphtheria
The most effective preventive method is vaccination. Diphtheria vaccination is part of national immunization programs:
- 1st dose: At 2 months of age
- 2nd dose: 1 month after the first dose
- 3rd dose: 1 month after the second dose
- 4th dose: At 18 months of age