A36.1 Nasopharyngeal diphtheria

Name of the Condition

• Nasopharyngeal diphtheria

Summary

Nasopharyngeal diphtheria is a localized form of diphtheria affecting the nasopharynx. It is caused by Corynebacterium diphtheriae and is characterized by the formation of a thick, adherent pseudomembrane in the nasal passages or pharynx. The infection may also produce a potent exotoxin that can lead to systemic complications, even if the primary site is limited to the nasopharynx.

Causes

Nasopharyngeal diphtheria is caused by infection with Corynebacterium diphtheriae, a gram-positive bacterium. The disease spreads through respiratory droplets or direct contact with an infected person’s respiratory secretions. The exotoxin produced by the bacteria is responsible for tissue damage and potential systemic effects.

Risk Factors

• Lack of vaccination or incomplete immunization against diphtheria.
• Close contact with an infected individual.
• Poor hygiene or crowded living conditions.
• Travel to regions with low vaccination coverage.

Symptoms

• Nasal discharge (often bloody or foul-smelling).
• Nasal obstruction or stuffiness.
• Sore throat and difficulty swallowing.
• Fever and chills.
• Swollen cervical lymph nodes (bull neck appearance).
• Thick, grayish-white pseudomembrane in the nasal passages or pharynx.
• Hoarseness or muffled voice.

Diagnosis

Diagnosis involves clinical assessment of symptoms, particularly the presence of the characteristic pseudomembrane. Laboratory tests, including throat or nasal swab cultures, confirm the presence of Corynebacterium diphtheriae. Toxin detection may also be performed to assess the risk of systemic complications.

Treatment Options

• Administration of diphtheria antitoxin to neutralize circulating toxin.
• Antibiotics (e.g., penicillin or erythromycin) to eradicate the bacterial infection.
• Supportive care, including airway management if obstruction occurs.
• Isolation to prevent spread to others.

Prognosis and Follow-Up

With prompt treatment, the prognosis for nasopharyngeal diphtheria is generally good, though complications can occur. Follow-up includes monitoring for signs of systemic toxin effects and ensuring completion of antibiotic therapy. Vaccination status should be assessed and updated if necessary.

Complications

• Airway obstruction due to membrane formation.
• Myocarditis (inflammation of the heart muscle) from toxin effects.
• Neurological complications, such as paralysis.
• Secondary bacterial infections.

Lifestyle & Prevention

• Ensure up-to-date diphtheria vaccination (DTaP, Tdap, or Td).
• Practice good hygiene, including handwashing.
• Avoid close contact with infected individuals.
• Seek medical care promptly if exposure is suspected.

When to Seek Professional Help

Seek immediate medical attention if you experience severe nasal discharge, difficulty breathing, high fever, or signs of airway obstruction. Early treatment is critical to prevent complications.

Tips for Medical Coders

When coding for nasopharyngeal diphtheria (A36.1), ensure documentation supports the specific anatomical site (nasopharynx) and confirms the presence of Corynebacterium diphtheriae or its toxin. Note any associated complications or treatment interventions, as these may impact coding specificity. Verify vaccination status and exposure history if available, as these details support clinical context.