Ritonavir-Induced Intraocular Pressure Elevation After Descemet's Stripping Endothelial Keratoplasty

This case report aims to highlight a rare but clinically significant complication of elevated intraocular pressure (IOP) after 4 years of Descemet's Stripping Endothelial Keratoplasty (DSAEK) and following the initiation of the antiretroviral medication Ritonavir. The report emphasizes the importance of considering systemic medications in the differential diagnosis of postoperative ophthalmic complications, particularly in patients with complex medical histories. It also provides guidance on the management of such cases and underscores the need for multidisciplinary collaboration to optimize patient outcomes.

The case occurred in Aristotle University of Thessaloniki, IInd Ophthalmology Department. The patient underwent DSAEKfor Fuchs' Endothelial Dystrophy 4 years prior to the even and was using topical Dexamethasone on alternate days. The patient was a 55-year-old male with a long-standing history of well-controlled HIV on antiretroviral therapy (ART) that was recently started on Ritonavir to improve pill burden and compliance. 

A 55-year-old male with Fuchs' Endothelial Dystrophy and a history of well-controlled HIV on ART was under annual review 4 years following uncomplicated DSAEK. Postoperatively, the patient was prescribed topical corticosteroids (G Dexamethasone), which he continued to use on alternate days for rejection prevention. The patient presented with elevated IOP (28 mmHg) and microcystic corneal edema. Initially, this was suspected to be a graft rejection episode, prompting the initiation of a high-dose topical steroid regimen. However, the IOP continued to rise, reaching 40 mmHg, and the corneal edema worsened.

Careful history-taking revealed that the patient had recently started Ritonavir, a protease inhibitor, as part of his ART regimen. Ritonavir was identified as a potential contributor to the elevated IOP, given its known systemic effects on intraocular pressure. The topical steroids were discontinued, and IOP-lowering medications (e.g., topical timolol and oral acetazolamide - temporarilly) were initiated. Additionally, the patient's HIV regimen was modified to exclude Ritonavir. Over the following three months, the IOP gradually normalized, and the corneal edema resolved without further complications.

1. Medication History is Critical: This case underscores the importance of obtaining a thorough medication history, including antiretroviral therapy, when evaluating postoperative complications. Ritonavir, a protease inhibitor, can contribute to elevated IOP, particularly when combined with topical corticosteroids.

2. Avoid Misdiagnosis: Elevated IOP and corneal edema following DSAEK can mimic graft rejection. Clinicians should carefully consider systemic medications as a potential cause before escalating steroid therapy.

3. Multidisciplinary Collaboration is Key: Collaboration with infectious disease specialists is essential to optimize ART regimens and minimize ocular complications in patients with complex medical histories.