Which Vitamin Deficiency Causes Keratitis? A Comprehensive Guide

October 11, 2025 •

2 min read

Worldwide, vitamin A deficiency is the leading cause of preventable childhood blindness, and a key factor in the development of a serious eye condition known as keratitis. This guide explores how a lack of vitamin A affects the cornea, leading to this severe inflammation, and what steps are necessary for diagnosis and treatment.

Quick Summary

Vitamin A deficiency is the primary cause of keratitis linked to nutritional deficits. The lack of this essential vitamin leads to eye dryness and abnormal cell differentiation, which can cause corneal ulceration and potentially blindness if untreated. Awareness and prompt supplementation are crucial.

Key Points

Primary Cause: Vitamin A deficiency, or hypovitaminosis A, is the main nutritional cause of keratitis, particularly its most severe form, keratomalacia.
Pathophysiology: Lack of vitamin A leads to the keratinization of the ocular surface, replacing mucin-secreting cells and causing severe dryness known as xerophthalmia.
Associated Symptoms: Early signs include night blindness, followed by conjunctival dryness (xerosis) and the formation of characteristic Bitot's spots.
Underlying Risk Factors: Malnutrition, malabsorption conditions (e.g., celiac disease, cystic fibrosis), chronic liver disease, and bariatric surgery can all lead to this deficiency.
Treatment Approach: Treatment involves immediate systemic vitamin A supplementation combined with topical antibiotics and lubricants to manage the corneal damage and associated infection.
Prevention: Prevention strategies include promoting a balanced diet rich in vitamin A sources and implementing public health supplementation programs in high-risk populations.

Understanding the Link Between Vitamin A and Keratitis

The primary nutritional cause of keratitis is a severe deficiency of vitamin A, a condition known as hypovitaminosis A. Vitamin A is crucial for the health of the ocular surface, including the cornea and conjunctiva. It helps maintain the normal differentiation of epithelial cells and promotes the production of mucin, a key component of the tear film. When vitamin A levels are inadequate, the normal mucin-secreting goblet cells on the ocular surface are replaced by keratinized, skin-like cells, a process called squamous metaplasia. This leads to severe dryness of the eye (xerophthalmia), which is a precursor to more severe corneal damage, including keratitis.

The Progression from Deficiency to Corneal Damage

The ocular manifestations of vitamin A deficiency progress through a series of stages, with keratitis representing a critical point in the disease. The stages include night blindness, conjunctival xerosis, Bitot's spots, corneal xerosis, and in the most severe cases, corneal ulceration and keratomalacia. Keratomalacia is the softening and liquefaction of the cornea, potentially leading to perforation and permanent blindness.

Factors Contributing to Vitamin A Deficiency

Beyond insufficient dietary intake, particularly in developing regions, factors such as malabsorption syndromes, gastrointestinal surgeries, chronic alcoholism, liver disease, and certain eating disorders can contribute to vitamin A deficiency.

Treatment and Management of Vitamin Deficiency Keratitis

Treating keratitis due to vitamin A deficiency involves simultaneously addressing the nutritional deficit and the ocular condition. This typically includes systemic vitamin A supplementation, topical antibiotic eye drops, ocular lubrication, and in severe cases, surgical intervention like corneal repair or transplant.

Keratitis Risk Factors: Nutritional vs. Other Causes

Keratitis can arise from both nutritional and other causes, such as infections, injury, or contact lens misuse. A comparison between vitamin deficiency keratitis and other forms highlights differences in primary cause, onset, underlying conditions, appearance, and key treatment approaches.

Conclusion

Vitamin A deficiency is the main nutritional cause of keratitis, a severe form of xerophthalmia that can result in corneal damage and blindness. Symptoms often start with night blindness and dry eyes, progressing if untreated. Diagnosis involves clinical signs and history. Treatment requires vitamin A supplementation and eye care. Though uncommon in developed countries, vigilance is needed for vulnerable individuals. Prevention through diet and supplementation is key. {Link: optometrists.org https://www.optometrists.org/general-practice-optometry/guide-to-eye-health/eyes-and-nutrition/}

Frequently Asked Questions

The primary vitamin deficiency that causes keratitis is a severe lack of vitamin A, also known as hypovitaminosis A.

A vitamin A deficiency impairs the function of epithelial cells on the eye's surface. This leads to dryness (xerophthalmia) and abnormal cell growth (keratinization), which makes the cornea vulnerable to inflammation and ulceration.

One of the earliest signs is night blindness (nyctalopia), which is difficulty seeing in low-light conditions. Conjunctival xerosis (dry conjunctiva) and Bitot's spots (foamy patches) are also common early indicators.

Vitamin A deficiency is rare in developed countries but can occur in individuals with specific health issues, such as chronic malabsorption syndromes, severe liver disease, or those with very restrictive diets.

Keratomalacia is the most severe and potentially blinding stage of vitamin A deficiency-induced keratitis, characterized by the softening and eventual melting of the cornea.

Treatment involves immediate systemic vitamin A supplementation to correct the deficiency, along with topical eye drops (antibiotics, lubricants) to manage the ocular inflammation and prevent secondary infections.

Yes, it can be prevented by ensuring a diet rich in vitamin A, especially in children and at-risk populations. Fortification programs and supplementation can also be highly effective.