Bitot’s spots are defined as triangular, white or foamy gray lesions appearing on the conjunctiva at the lateral margin of the cornea. They vary in appearance from a few bubbles to a frothy white coating and are a clinical sign of vitamin A deficiency.

Pathophysiology

• Vitamin A is essential for maintaining healthy epithelial tissues and visual pigments (rhodopsin) in the retina.

• Deficiency leads to keratinization of the conjunctival epithelium, producing the foamy or triangular lesions observed as Bitot’s spots.

• Chronic deficiency may progress to xerophthalmia, night blindness, corneal ulceration, and potentially blindness if untreated.

Examination Technique

• Patient positioning: Seated or supine with eyes open and looking straight ahead.

• Inspection:

  1. Examine the temporal (lateral) conjunctiva of both eyes.

  2. Identify white, triangular, or foamy patches on the bulbar conjunctiva.

  3. Assess for dryness, conjunctival thickening, or other ocular surface changes.

• Interpretation:

  • The presence of triangular foamy lesions on the lateral conjunctiva is highly suggestive of vitamin A deficiency.

  • Often accompanied by xerosis of the conjunctiva and cornea.

Clinical utility

• Early marker of vitamin A deficiency: Bitot’s spots appear before severe ocular damage occurs.

• Indicator for nutritional assessment: Triggers evaluation of dietary intake, malabsorption, or systemic illness.

• Monitoring response to supplementation: Spots may regress after adequate vitamin A therapy.

Differential Diagnosis

Management

• Vitamin A supplementation: Oral or intramuscular high-dose vitamin A therapy according to WHO guidelines.

• Dietary intervention: Increase intake of vitamin A-rich foods such as liver, dairy, eggs, and yellow/orange vegetables.

• Monitoring: Regular follow-up to assess regression of Bitot’s spots and improvement in vision.

• Address underlying causes: Treat malabsorption syndromes or chronic illnesses that contribute to deficiency.

Pediatric considerations

• Children are particularly vulnerable to vitamin A deficiency due to higher nutritional requirements.

• Bitot’s spots in children may be accompanied by night blindness or growth retardation.

• Early detection and supplementation can prevent irreversible blindness.

Geriatric considerations

• Older adults may develop Bitot’s spots due to malnutrition, chronic illness, or fat malabsorption.

• Consider multivitamin supplementation and dietary counseling in at-risk populations.

Limitations

• Bitot’s spots indicate chronic vitamin A deficiency; early deficiency may not produce visible lesions.

• Other ocular surface disorders can mimic the appearance; clinical correlation and dietary history are essential.

Patient counseling

• Educate the patient about the importance of vitamin A-rich foods.

• Emphasize adherence to supplementation schedules.

• Advise regular eye examinations to monitor for progression or complications.

Conclusion

Bitot’s spots are a classic ocular sign of vitamin A deficiency and serve as an important marker for nutritional assessment and early intervention. Timely recognition and management can prevent progression to xerophthalmia and blindness, making this sign critical in both pediatric and adult populations.

References

1. Sommer A. Vitamin A deficiency and clinical disease: An historical overview. J Nutr. 2008;138(10):1835–1839.

2. West KP Jr, Darnton-Hill I. Vitamin A Deficiency. 2nd ed. Geneva: WHO; 2008.

3. Buttaro TM, Tybulski J, Bailey PP, Sandberg-Cook J. Primary Care: A Collaborative Practice. St. Louis, MO: Mosby Elsevier; 2008. p. 444–447.

4. Sommer A, Davidson FR. Assessment and control of vitamin A deficiency: The Annecy Accords. Food Nutr Bull. 2002;23(3 Suppl):S1–S3.

5. Furr HC, Clark RM. Nutritional deficiencies and their ocular manifestations. Optometry & Vision Science. 2011;88(10):E1220–E1230.