What is the treatment for nasal myiasis?

Treatment of Nasal Myiasis

The most effective treatment for nasal myiasis is a combination of nasal irrigation with ivermectin solution followed by manual removal of larvae under endoscopic guidance, supplemented with oral ivermectin when necessary.

Clinical Presentation and Diagnosis

Nasal myiasis is a parasitic infestation of the nasal cavities by fly larvae (maggots), commonly seen in tropical regions. Key clinical features include:

• Nasal obstruction
• Purulent rhinorrhea
• Facial pain or pressure
• Epistaxis
• Sensation of movement within the nasal cavity
• Visible larvae on examination

Risk Factors

Several conditions predispose patients to nasal myiasis:

• Atrophic rhinitis (most common predisposing factor) 1
• Impaired consciousness 2
• Poor hygiene
• Facial trauma or wounds
• Immunocompromised status
• Nasal or facial sequelae of conditions like leprosy 3
• Lack of protective reflexes (sneezing, coughing)

Treatment Algorithm

First-Line Treatment

1. Nasal Irrigation with Ivermectin Solution

   • Highly effective for expulsion of larvae 4
   • Patients may self-expulse numerous larvae within minutes of irrigation
   • Technique: Irrigate nasal cavities with ivermectin solution under medical supervision

2. Endoscopic Removal

   • Superior to manual extraction 5
   • Allows visualization of larvae in deep and inaccessible areas
   • Reduces number of required treatment sessions
   • Enables complete eradication before irreparable tissue damage occurs

3. Systemic Treatment

   • Oral ivermectin for cases with extensive infestation 4, 3
   • Appropriate antibiotics if secondary bacterial infection is present

Alternative/Adjunctive Treatments

• Traditional method: Packing the nose with chloroform and turpentine (1:4) mixture followed by manual removal of dead larvae 1
• Continuous nasal hygiene with saline irrigation to prevent reinfestation
• Topical antibiotics for secondary infections

Management of Complications

Larvae can cause extensive erosion of:

• Nasal tissues
• Facial structures
• Intracranial structures (in severe cases)

Potential complications include:

• Meningitis
• Orbital invasion
• Extensive tissue necrosis
• Death (rare)

Prevention of Recurrence

1. Treat Underlying Conditions

   • Management of atrophic rhinitis
   • Regular nasal hygiene with saline irrigation
   • Treatment of predisposing factors

2. Environmental Control

   • Proper isolation of affected patients in hospital settings 2
   • Prevention of fly exposure
   • Improved hygiene practices

Special Considerations

In patients with severe nasal sequelae (as seen in leprosy), long-term follow-up is essential as recurrence may occur even after successful initial treatment 3.

Pitfalls to Avoid

1. Incomplete removal of larvae leading to continued tissue destruction
2. Failure to identify and treat deep-seated larvae in paranasal sinuses
3. Neglecting treatment of underlying predisposing conditions
4. Inadequate follow-up, especially in high-risk patients

The combination of ivermectin irrigation and endoscopic removal represents the most modern and effective approach to treating this potentially serious condition, with significantly better outcomes than traditional manual extraction methods alone.