Microsporidial keratoconjunctivitis may mimic allergy

Molecular testing identified Encephalitozoon hellem in a 9-year-old orthokeratology lens wearer after conventional treatment failed.

By
Andrea Surnit
September 16, 2026
4 min

MDSpire News

Background

Microsporidial keratoconjunctivitis is a rare condition that can mimic allergic conjunctivitis, leading to misdiagnosis and inappropriate treatment. Understanding its clinical presentation and risk factors is crucial for timely diagnosis and management, particularly in patients who wear contact lenses.

Data Highlights

No numerical or trial data provided in the source material.

Key Findings

A 9-year-old female patient presented with bilateral eye symptoms initially diagnosed as allergic conjunctivitis.
Conventional treatment with antiallergic eye drops was ineffective, prompting further investigation.
In vivo confocal microscopy and anterior segment optical coherence tomography revealed significant corneal changes.
Metagenomic next-generation sequencing confirmed the diagnosis of microsporidial keratoconjunctivitis caused by Encephalitozoon hellem.
The patient showed significant improvement with targeted therapy, including chlorhexidine and levofloxacin eye drops.
Prolonged orthokeratology lens wear and exposure to pet parrots were identified as potential risk factors.

Clinical Implications

Clinicians should consider microsporidial keratoconjunctivitis in patients with persistent keratoconjunctivitis that does not respond to standard allergy treatments.