Abstract:

Alpha-interferon (α-IFN) therapy has been a cornerstone in the treatment of chronic viral hepatitis, particularly hepatitis B and C. While effective, its association with various ophthalmologic side effects has raised concerns among clinicians. This review aims to systematically examine the nature, incidence, risk factors, and management strategies of eye-related complications during α-IFN therapy. Through an analysis of prospective studies, case reports, and clinical trials, we highlight the spectrum of ocular manifestations, ranging from asymptomatic retinal changes to severe neurovisual impairments. Factors such as hypertension, advanced age, and the use of pegylated interferon are identified as significant risk determinants. Early detection through regular ophthalmologic monitoring is emphasized, with recommendations for dose adjustments or discontinuation in symptomatic cases. This review underscores the importance of vigilance in the ophthalmologic assessment of patients undergoing α-IFN therapy to mitigate potential visual complications.

 

Introduction:

Alpha-interferon (α-IFN) has been extensively utilized in the management of chronic viral hepatitis, notably hepatitis B and C. Its antiviral, antiproliferative, and immunomodulatory properties contribute to its therapeutic efficacy. However, the systemic administration of α-IFN is not without adverse effects, particularly concerning the ocular system. Ophthalmologic complications associated with α-IFN therapy can range from mild, asymptomatic retinal changes to severe visual disturbances, potentially impacting patient quality of life. Understanding the spectrum of these ocular side effects, their underlying mechanisms and the associated risk factors is crucial for optimizing patient management and preserving visual function.

 

Discussion:

  1. Spectrum of Ophthalmologic Side Effects:

The ocular manifestations of α-IFN therapy encompass a broad range of conditions:

  • Retinopathy: The most frequently reported ocular complication, characterized by cotton wool spots, retinal hemorrhages, and microaneurysms. These changes are often asymptomatic and reversible upon discontinuation of therapyNeurovisual Impairments: Patients may experience alterations in visual evoked potentials, visual field defects, and contrast sensitivity. These subclinical changes can progress to symptomatic neurovisual disturbances if not monitored appropriately.
  • Glaucoma: Elevated intraocular pressure leading to optic nerve damage has been observed, particularly in patients with predisposing factors such as hypertension. In some cases, glaucoma symptoms improved upon cessation of α-IFN therapy. Anterior Ischemic Optic Neuropathy: A rare but serious complication resulting in sudden, painless vision loss, often associated with systemic vascular risk factors.
  • Other Manifestations: Includes trichomegaly (increased length of eyelashes), conjunctivitis, dry eye, and photophobia. These are generally less severe but can affect patient comfort and adherence to therapy. 2. Risk Factors:

Several factors have been identified that increase the likelihood of developing ocular complications during α-IFN therapy: Hypertension: A significant risk factor for the development of retinopathy and glaucoma.

  • Advanced Age: Patients over 45 years are at higher risk for retinal changesUse of Pegylated Interferon: The sustained-release formulation has been associated with a higher incidence of retinal abnormalities compared to standard α-IFN. Diabetes Mellitus: Although not conclusively proven, diabetic patients may have an increased risk of ocular complications
  1. Mechanisms of Ocular Toxicity:

The exact pathophysiological mechanisms underlying α-IFN-induced ocular toxicity remain under investigation. Proposed mechanisms include:

  • Vascular Endothelial Growth Factor (VEGF) Modulation: α-IFN may influence VEGF expression, leading to vascular changes in the retina.
  • Immune-Mediated Inflammation: Alterations in immune response may result in inflammatory changes affecting ocular structures.
  • Direct Toxic Effects: Direct cytotoxic effects of α-IFN on retinal cells have been suggested.
  1. Management Strategies:

Early detection through regular ophthalmologic evaluations is paramount. Recommended strategies include:

  • Baseline and Periodic Fundoscopic Examinations: To identify early retinal changes.
  • Monitoring of Visual Function: Assessment of visual acuity, visual fields, and contrast sensitivity.
  • Management of Systemic Risk Factors: Control of hypertension, diabetes, and other vascular risk factors.
  • Dose Adjustment or Discontinuation: In cases of symptomatic ocular complications, modifying the α-IFN dosage or discontinuing therapy may be necessary.
  1. Prognosis:

Most ocular side effects are reversible upon cessation of α-IFN therapy. However, severe complications such as ischemic optic neuropathy may result in permanent visual impairment. Therefore, proactive monitoring and timely intervention are crucial to prevent lasting damage.

Methodology:

This comprehensive review synthesizes data from a range of sources, including:

  • Prospective Studies: Randomized controlled trials and cohort studies assessing ocular outcomes in patients undergoing α-IFN therapy.

References

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