Pathology of iris in leprosy

Area of Science:

• Ophthalmology
• Pathology
• Infectious Diseases

Background:

• Leprosy, a chronic infectious disease, can affect various organs, including the eye.
• Ocular manifestations in leprosy, such as iridocyclitis, can lead to significant visual impairment.
• Subclinical ocular involvement in leprosy remains underdiagnosed.

Purpose of the Study:

• To investigate the histopathological features of the iris in leprosy patients.
• To identify the presence of acid-fast bacilli (AFB) in iris tissue.
• To correlate histopathological findings with clinical presentation.

Main Methods:

• Light microscopy was used to examine formalin-fixed, paraffin-embedded iris tissue from 20 leprosy patients undergoing cataract surgery.
• Tissue sections were stained with hematoxylin and eosin and modified Fite Faraco's stain for AFB.
• Clinical data, including evidence of iridocyclitis, were reviewed.

Main Results:

• Chronic inflammatory reactions were observed in the iris of 11 patients (55%), with seven showing no clinical signs of iridocyclitis.
• Smooth muscle disruption and destruction were noted in two specimens.
• AFB were detected in the iris tissue of one borderline lepromatous patient with negative skin smears who had completed multidrug therapy (MDT).

Conclusions:

• Histopathology reveals a higher prevalence of silent chronic iridocyclitis in leprosy patients than clinically diagnosed.
• Acid-fast bacilli (AFB) can persist in iris tissue even after completion of MDT.
• Smooth muscle disruption and destruction in the iris, a potential cause of miotic pupil in leprosy, are histopathologically confirmed.