B73.01 Onchocerciasis with endophthalmitis

Name of the Condition

• Onchocerciasis with endophthalmitis

Summary

Onchocerciasis with endophthalmitis is a parasitic infection caused by Onchocerca volvulus that involves inflammation of the inner eye structures (endophthalmitis). The condition results from the migration of microfilariae to ocular tissues, leading to inflammatory responses and potential vision-threatening complications. Chronic infection may progress to severe visual impairment or blindness, particularly in endemic regions where vector exposure is common.

Causes

Onchocerciasis with endophthalmitis is caused by the filarial worm Onchocerca volvulus, transmitted through the bite of infected blackflies (Simulium species). The larvae mature into adult worms in subcutaneous tissue, producing microfilariae that migrate to ocular structures. Inflammatory responses to these microfilariae drive the development of endophthalmitis and related symptoms.

Risk Factors

• Residence in or travel to areas with endemic Simulium blackfly populations.
• Prolonged outdoor exposure near fast-flowing rivers or streams.
• Lack of access to vector control or mass drug administration programs.
• Immunological factors influencing susceptibility to ocular involvement.

Symptoms

• Eye pain or discomfort.
• Visual disturbances, including blurriness or reduced acuity.
• Photophobia (sensitivity to light).
• Conjunctival inflammation or corneal opacity.
• Potential progression to severe vision loss.

Diagnosis

Diagnosis involves clinical evaluation of ocular symptoms, history of exposure to endemic areas, and laboratory testing. Microscopic examination of skin snips or ocular samples may detect microfilariae. Imaging studies, such as ultrasound or optical coherence tomography, can assess intraocular inflammation. Serological tests or PCR may confirm Onchocerca volvulus infection.

Treatment Options

Treatment typically includes antiparasitic medications, such as ivermectin, to target the microfilariae. Corticosteroids or anti-inflammatory agents may be used to manage ocular inflammation. In severe cases, surgical intervention may be necessary to address complications like cataracts or retinal detachment.

Prognosis and Follow-Up

Prognosis depends on the severity of ocular involvement and timeliness of treatment. Early intervention can prevent progression to blindness, but chronic infection may lead to permanent vision loss. Regular follow-up with an ophthalmologist is recommended to monitor for recurrence or complications.

Complications

• Permanent vision loss or blindness.
• Retinal detachment.
• Cataracts.
• Chronic ocular inflammation.
• Secondary infections.

Lifestyle & Prevention

• Avoid outdoor activities near fast-flowing rivers or streams in endemic areas.
• Use insect repellent and protective clothing to reduce blackfly bites.
• Participate in mass drug administration programs in endemic regions.
• Seek prompt medical care for ocular symptoms after potential exposure.

When to Seek Professional Help

Consult a healthcare provider if you experience persistent eye pain, vision changes, or exposure to endemic areas. Immediate evaluation is necessary for sudden vision loss or severe ocular discomfort.

Tips for Medical Coders

Use code B73.01 for onchocerciasis with endophthalmitis. Document the presence of intraocular inflammation and confirm the parasitic etiology. Ensure clinical details support the specific ocular manifestation to justify code assignment.