Mycobacterial Disease in Ophthalmology
Introduction: Mycobacterial diseases are caused by bacteria belonging to the genus Mycobacterium, with several species known to affect the eyes. These infections can lead to a wide spectrum of ocular manifestations, ranging from anterior segment inflammations to posterior segment involvement.
Types of Mycobacterial Diseases:
- Tuberculosis (TB) Uveitis:
- Clinical Features:
- TB uveitis encompasses a spectrum of inflammatory conditions affecting the uveal tract, including anterior uveitis, intermediate uveitis, and posterior uveitis.
- Patients may present with granulomatous anterior chamber reaction, iris nodules, vitritis, and choroidal tubercles.
- Diagnosis and Management:
- Diagnosis involves a combination of clinical findings, tuberculin skin testing, interferon-gamma release assays, chest imaging, and aqueous or vitreous sampling for Mycobacterium tuberculosis PCR.
- Treatment typically consists of systemic anti-tubercular therapy combined with corticosteroids to control inflammation.
- Clinical Features:
- Atypical Mycobacterial Keratitis:
- Clinical Features:
- Atypical mycobacterial keratitis, often caused by species like Mycobacterium chelonae and Mycobacterium abscessus, presents as a chronic, indolent corneal infection.
- Patients may develop corneal infiltrates, epithelial defects, and stromal thinning, leading to vision loss if left untreated.
- Diagnosis and Management:
- Diagnosis relies on corneal scrapings for acid-fast bacilli staining, culture, and molecular techniques.
- Treatment involves prolonged antimicrobial therapy with agents like clarithromycin, amikacin, and fluoroquinolones, often in combination with surgical debridement.
- Clinical Features:
Conclusion: Mycobacterial diseases pose diagnostic and therapeutic challenges in ophthalmology due to their diverse clinical presentations and variable treatment responses. Early recognition, accurate diagnosis, and timely initiation of targeted antimicrobial therapy are crucial in managing these infections and preventing sight-threatening complications.
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