Kidney disease can cause visible changes in the eyes. As kidney function declines, fluid can accumulate in the body and cause swelling or puffiness around the eyes. Some specific eye changes that can occur with kidney disease include:
Dark Circles Under the Eyes
Dark circles under the eyes are a common early sign of kidney disease. This happens due to an accumulation of waste products and excessive fluid (edema) under the thin skin below the eyes. The skin can take on a dark bluish-gray color due to the buildup of waste products. Dark under eye circles are often most noticeable upon waking up in the morning.
Puffy Eyes/Eyelids
Another early sign of kidney problems is puffy or swollen eyes. This occurs because the kidneys are not able to effectively remove excess fluid from the body. The puffiness is due to a build up of fluid in the delicate tissues around the eyes. The swelling can cause the eyelids to appear puffy or swollen. In some cases, the puffiness may be more pronounced in the morning.
Drooping Eyelids
Some kidney disease patients develop a drooping of their upper eyelid, which doctors call ptosis. When the kidneys aren’t working well, an excessive build up of toxins in the blood can cause inflammation or damage to the muscles that control eyelid opening and closure. This can make the eyelid appear heavy and start to droop.
Dry, Itchy Eyes
Many kidney disease patients experience dry eyes and eye irritation. This happens because the kidneys are not able to maintain the right balance of fluid in the body. Insufficient tear production can result in dry, gritty, itchy eyes. Some patients describe having a “sandy” feeling in their eyes. Severely dry eyes are prone to infections.
Pale Conjunctiva
The conjunctiva is the thin, transparent tissue that covers the whites of the eyes. In advanced kidney failure, the conjunctiva can become pale, giving the whites of the eyes a washed-out, pale look. This paleness occurs due to anemia, which is a low red blood cell count. Severe anemia is common in late-stage kidney disease.
Retinal Changes
The retina is the light-sensitive tissue at the back of the eye. Different types of lesions, bleeding, and other abnormalities can occur in the retinas of patients with chronic kidney disease. These retinal changes are often seen during an eye exam. Common retinal findings include:
- Hemorrhages – bleeding in the retina
- Exudates – lipid or protein deposits that look like pale yellow spots
- Macular edema – swelling or thickening of the macula (central retina)
These retinal changes can sometimes affect vision if the macula or central vision is involved. The retinal abnormalities are caused by a combination of high blood pressure, fluid overload, and other impairments of kidney function.
Lens Changes
The lens of the eye can also be affected by long-standing kidney disease. Some patients develop a clouding of the clear lens called a cataract. Cataracts cause blurry vision, glare sensitivity, and other vision problems that get worse over time. Cataracts tend to form at an earlier age in kidney failure patients compared to the general public. The cataracts are usually caused by an accumulation of waste products in the lens.
Optic Nerve Damage
The optic nerve carries vision signals from the eye to the brain. Swelling of the optic nerve (optic disc edema) can occur in patients with sudden kidney failure. In chronic kidney disease, the optic nerve is often atrophied, meaning it has gradually worn away. This nerve damage leads to vision loss.
Corneal Abnormalities
The cornea is the clear front surface of the eye. Kidney patients can develop edema and swelling of the cornea or have abnormal corneal deposits. These abnormalities are seen on slit lamp examination of the eye. If the swelling becomes severe, it can affect vision and cause sensitivity to light.
Glaucoma
Glaucoma refers to an increase in pressure inside the eye, which damages the optic nerve over time. Kidney failure patients are at increased risk for glaucoma because of their fluid imbalance. The excess fluid can cause a dangerous buildup of eye pressure. Glaucoma causes gradual vision loss and needs to be treated to prevent blindness.
Uremic Frost
In severe kidney failure, a buildup of urea in the tears can cause a frosty-white deposit on the skin around the eyes. These deposits are called uremic frost. The urea in tears crystallizes and leaves a white crusty deposit around the eyes, especially at the inner corners. Uremic frost can also form on the eyebrows and beard.
Table Summarizing Eye Changes in Kidney Disease
| Eye Change | Description |
|---|---|
| Dark circles under eyes | Bluish discoloration under eyes caused by waste buildup and fluid retention. |
| Puffy eyelids | Swollen eyelids from fluid retention in the eye area. |
| Drooping eyelids | Eyelid muscles weaken and cause drooping. |
| Dry, irritated eyes | Insufficient tear production leading to dryness and irritation. |
| Pale conjunctiva | Anemia causes paleness of the whites of the eyes. |
| Retinal changes | Hemorrhages, exudates, and other lesions in the retina. |
| Cataracts | Clouding and opacification of the eye lens. |
| Optic nerve damage | Swelling or atrophy of the optic nerve fibers. |
| Corneal abnormalities | Swelling, edema, and deposits on the cornea. |
| Glaucoma | Increased pressure inside the eye. |
| Uremic frost | Crystallization of urea from tears causing a white crust on the skin around eyes. |
What Causes These Eye Changes?
The eyes are directly impacted by kidney dysfunction in multiple ways:
- Fluid imbalance – Excess fluid accumulates in the soft tissues around the eyes.
- Waste buildup – Toxins that are not filtered by the kidneys deposit in the eyes.
- Anemia – Kidney failure reduces red blood cell production causing anemia.
- High blood pressure – Uncontrolled hypertension is damaging to the small vessels and nerves of the eyes.
- Inflammation – Kidney disease provokes inflammation which can affect delicate eye tissues.
- Hormone imbalance – The kidneys regulate hormones that can impact eye health when imbalanced.
These complex changes in body physiology directly impact the health and appearance of the eyes in kidney disease patients.
Can Vision Be Affected?
Yes, many of the ocular changes caused by kidney disease can affect vision and eye health. Some of the key ways kidney problems impact vision include:
- Retinal bleeding or detachment – This can cause spots, floaters, or blind areas in the visual field.
- Macular edema – Swelling in the macula damages central vision making activities like reading difficult.
- Cataracts – Gradual visual blurring and loss of contrast sensitivity.
- Optic nerve damage – Irreversible loss of peripheral vision or tunnel vision.
- Glaucoma – Pressure damage causes gradual loss of side vision.
- Corneal swelling – Extreme swelling distorts vision.
Sudden or rapid vision changes in a kidney patient require urgent medical evaluation to determine the cause and prevent permanent damage.
Are the Eye Changes Reversible?
Some eye changes may be reversible if kidney function improves. For example:
- Puffiness and dark circles can resolve as fluid balance is restored.
- Dry eyes may improve with kidney function and hormonal regulation.
- Anemia can be treated with supplements and medications to restore the conjunctiva.
- Cataracts can be surgically removed to restore vision.
However, some eye damage can be permanent if the kidney disease has been long-standing. Examples of potentially irreversible damage include:
- Atrophied optic nerves cannot be restored.
- Retinal bleeding, detachment and macular scarring can lead to uncorrectable vision loss.
- Glaucomatous optic nerve damage cannot be reversed.
The degree to which eye abnormalities will resolve depends on the duration and severity of kidney dysfunction. That’s why it’s crucial to monitor vision and get regular eye exams in kidney disease patients. Catching problems early provides the best chance of preserving vision.
Can Dialysis Help Eye Problems?
Yes, dialysis can help improve some eye abnormalities by filtering waste products from the blood and restoring fluid balance. Benefits of dialysis include:
- Removing toxins that deposit in the eyes.
- Correcting anemia to return blood oxygen levels to normal.
- Reducing blood pressure which protects the tiny eye vessels.
- Balancing fluid levels and reducing puffy eyes.
That being said, dialysis cannot reverse damage that has already occurred in the eyes. But it can certainly help stabilize vision and prevent further deterioration in many cases.
Table Comparing Eye Changes Before and After Dialysis
| Eye Change | Before Dialysis | After Dialysis |
|---|---|---|
| Dark circles | Severe | Mild to moderate improvement |
| Puffy eyelids | Marked swelling | Reduced swelling |
| Conjunctival paleness | Very pale conjunctiva | Some improvement in color |
| Cataracts | Rapid worsening | Slowed progression |
| Retinal changes | New hemorrhages | Stabilized |
| Optic nerve edema | Moderate to severe | Slightly reduced swelling |
Will a Kidney Transplant Fix the Eye Problems?
A successful kidney transplant can stabilize and sometimes even reverse damage to the eyes caused by kidney disease. With a functioning donor kidney, many aspects of eye health improve including:
- Fluid balance regulation prevents puffy and dry eyes.
- Waste toxin removal prevents deposits in the eyes.
- Anemia is corrected allowing pink, healthy conjunctiva.
- Improved blood pressure benefits the retinal blood vessels.
- Inflammation reduction helps stabilize glaucoma and other conditions.
A kidney transplant before end-stage renal disease gives the best chance of recovering eye health and vision. But even patients with long-standing kidney failure may see stabilization and some reversal of ocular changes after transplantation.
Key Points
- Kidney disease affects many structures in the eye including the eyelids, conjunctiva, retina, lens, optic nerve and cornea.
- Some of the most common visible changes are dark circles under the eyes, puffy eyelids, pale conjunctiva, and corneal swelling.
- Inside the eye, kidney disease causes damage to the retina, optic nerve and other structures that can impair vision.
- Sudden vision changes in a person with kidney failure require prompt medical attention to prevent permanent visual loss.
- Treatments like dialysis and kidney transplant can stabilize and sometimes reverse eye changes from chronic kidney disease.
Conclusion
Kidney disease has a multidimensional impact on ocular health and appearance. Fluid imbalance, waste buildup, anemia, hypertension and inflammation associated with malfunctioning kidneys result in visible changes to the eyes. Dark circles, puffiness and conjunctival pallor are some of the earliest outward signs of kidney dysfunction. Inside the eyes, worsening damage can occur in the retinas, lens, optic nerves and other structures – impairing vision and eye health. While some changes may be reversible if caught early, others can lead to permanent blindness if left unchecked. That’s why regular eye exams and urgent evaluation of any vision changes are so important in this vulnerable patient population. With diligent monitoring and proper treatment, further damage can often be prevented.