Now accepting Telehealth appointments. Schedule a virtual visit.

Hydroxychloroquine induced retinal toxicity

Chloroquine (CQ) and hydroxychloroquine (Plaquenil) (HCQ) have been used for many years, initially for the treatment of malaria but now more commonly for the treatment of inflammatory diseases such as rheumatoid arthritis and lupus . It is now considered for new disease applications in diabetes, heart disease and adjunct cancer therapies.

Ocular manifestations of hydroxychloroquine include corneal verticillata and retinal toxicity. Verticillata are cornea deposits of salts within the corneal epithelium.  This condition does not cause symptoms and is reversible with cessation of the medication. The finding of corneal verticillata bares no correlation with retinal toxicity and is not an indication to stop the medication . The hallmark of hydroxychloroquine toxicity is bilateral pigmentary retinopathy . Patients with early retinal findings are often asymptomatic despite having subtle paracentral scotomas. Later in the disease, patients can develop a bilateral bull's eye maculopathy, characterized by a ring of retinal pigment epithelium (RPE) depigmentation in the macula, sparing the fovea, which is often accompanied by paracentral and central scotomas . End stage hydroxychloroquine toxicity leads to widespread RPE and retinal atrophy with a loss of central vision, peripheral vision, and night vision.

The most important risk for toxicity is excessive daily dose by weight . Dosage >5.0mg/kg increases the risk of toxicity. Duration of use is also a critical risk factor. HCQ is cleared by the kidneys and thus renal disease increases the risk of toxicity. Tamoxifen (used in breast cancer treatment) increases the risk of toxicity approximately 5 fold. 

All patients should have a baseline Eye examination within the first year of initiating HCQ or CQ therapy with thorough risk factor assessment and fundus examination of the macula to rule out underlying disease. Baseline VFs and OCT are also recommended. Annual Exams are recommended as well.

Author
Paddy Kalish OD, JD and B.Arch

You Might Also Enjoy...

ANEURYSM

An aneurysm is a bulging, weakened area in the wall of a blood vessel resulting in an abnormal widening or ballooning greater than 50% of the vessel's normal diameter (width). An aneurysm may occur in any blood vessel, but is most often seen in an artery.

NITRIC OXIDE and Health

Nitric oxide (NO) is one of the critical components of the vasculature, regulating key signaling pathways in health. In macro-vessels, NO functions to suppress cell inflammation as well as adhesion.

SEPSIS

Sepsis is a serious condition in which the body responds negatively to an infection. The infection fighting processes turn on the body, causing the organs to work malfunction. Sepsis may progress to septic shock.

MERKEL CELL Carcinoma(MCC)

Merkel cell carcinoma is a rare type of skin cancer that usually appears as a flesh-colored or bluish-red nodule, often on the Face, Eyelid, Head or Neck.

Sciatica

Sciatica refers to pain, weakness, numbness, or tingling in the leg. It is caused by injury to or by pressure on the sciatic nerve. Sciatica is a symptom of a medical problem. It is not a medical condition by itself.

HEART FAILURE

HEART FAILURE is a condition in which the heart loses efficiency, leading to a chronic mismatch between the body’s need for oxygen and what it actually gets. There is chronic difficulty breathing, uncomfortable swelling in the arms or legs (or anywhere).