The sclera is the outer coating of the eyeball — commonly called the “white of the eye.”
It consists of tough fibrous connective tissue that envelops the eyeball and frames the cornea. The sclera supports the eye’s shape and shields it from minor injuries.
When clinicians describe an anicteric sclera, they mean the white of the eye remains white — there’s no yellow tint and it looks normal.
By contrast, an icteric sclera refers to a yellowed white of the eye. That yellowing most often signals jaundice, which can stem from multiple causes.
Both sclerae and scleras are acceptable plural forms of sclera.
Read on as we outline the differences between anicteric and icteric sclera and review signs that warrant medical attention.
Normal, healthy sclera
When a clinician gently pulls down your lower eyelids and asks you to gaze upward, they’re usually inspecting the sclera and conjunctiva. The conjunctiva is the thin membrane covering the front of the eye and lining the inside of the eyelids.
In a healthy eye, the conjunctiva is translucent and the sclera is white. An anicteric sclera indicates that the white part of the eye lacks yellow discoloration and appears healthy.
Possible reasons for an icteric sclera
You’ve likely experienced red or bloodshot eyes at times from irritation, allergies, or sleep deprivation. Those are common and usually harmless.
An icteric sclera, however, is uncommon and suggests an underlying issue. The most frequent culprit is jaundice.
Jaundice
Jaundice is a condition in which the skin and the whites of the eyes take on a yellow hue. It’s very rare for only one eye to display icterus.
Jaundice results from excessive bilirubin. Bilirubin is a yellow-orange substance generated as the body breaks down old red blood cells.
The liver normally processes bilirubin so it can be eliminated in the stool.
If the body produces too much bilirubin or the liver cannot process it effectively, bilirubin accumulates and causes the skin and eyes to appear yellow.
Other signs of jaundice might include:
- dark urine
- fever
- itchiness
- pale stools
- nausea
- abdominal pain
- weight loss
Newborns may develop jaundice because they lack sufficient levels of certain liver enzymes. Other causes of jaundice include:
- bile duct obstruction
- hematologic disorders
- cancers of the gallbladder or pancreas
- specific kinds of anemia
- cirrhosis
- excessive alcohol use
- gallstones
- hepatitis or other liver infections
- genetic conditions such as Crigler-Najjar, Dubin-Johnson, and Gilbert syndromes
- pancreatitis
- certain medications
For further context about how jaundice may present in different populations, you may find useful information on jaundice in black people.
Pinguecula
If you notice a raised, yellowish patch on the white of your eye, it might be a pinguecula. These tend to appear on the area nearest the nose.
Unlike jaundice, which affects the whites of both eyes, a pinguecula typically involves only a small localized portion of one eye.
Other symptoms can include:
- redness
- irritation
- a sensation of something in the eye
Pingueculae develop on the conjunctiva rather than the sclera. They arise from abnormal deposits of protein and fat, possibly related to chronic irritation or prolonged ultraviolet light exposure.
When to seek medical care
The sclerae should normally look white. If they appear yellow, it’s more than a cosmetic issue and won’t resolve on its own.
If you have red spots or what seems to be a pinguecula, consult an eye specialist.
If both eyes are becoming yellow, that’s likely a sign of jaundice — contact a clinician promptly.
Treatment for jaundice depends on the underlying cause.
Medical emergencyJaundice can be caused by severe, potentially life-threatening conditions. Call your healthcare provider or go to the nearest emergency department if you suspect jaundice.
Key points
An anicteric sclera indicates the white of the eye appears white and healthy. An icteric sclera means the white of the eye is yellowed, usually signaling jaundice.
Many different conditions can lead to jaundice, including disorders of the liver, pancreas, or gallbladder.
If your eyes are turning yellow, arrange to see a healthcare professional as soon as possible.
Leave a Reply
You must be logged in to post a comment.