Xerophthalmia is a condition induced by severe vitamin A deficiency, that affects the ocular organelles of the cornea, retina, conjunctivitis in the eyes. Vitamin A plays a crucial role in the operations of the visual organelles, including preserving the optimal production of tears – the fluid secretions that help in maintaining a moist environment all around the eyeballs.
Hence, a chronic lack of this vital nutrient leads to dryness in the cornea and conjunctiva, which if left unattended, progresses on to more severe stages, ultimately resulting in dry eye syndrome, corneal ulceration and even blindness owing to damage to the tissues of the cornea and retina. However, timely treatment with vitamin A supplementation significantly improves visual functions and eye health.
Causes Of Xerophthalmia:
The chief factor triggering xerophthalmia is a lack of vitamin A. Vitamin A is an essential nutrient that is not synthesised by the body and thus, must be obtained from the diet. Moreover, it is responsible for central functions in the eyes, such as forming a component of proteins that absorb light rays in the retinal receptors, enhancing the structure and operations of the conjunctiva, cornea, optic nerve and also stimulating the lacrimal glands.
The lacrimal glands are involved in the synthesis and secretion of tears – the watery components, in addition to electrolytes and protective proteins, that are transformed into an aqueous gel by the cornea and conjunctiva and in turn, help lubricate the eyes. Therefore, when there is a vitamin A deficiency, it ultimately leads to xerophthalmia, with dry eyes and white spots, ulcers on the ocular organelles.
Certain aspects make an individual more prone to contracting xerophthalmia, including:
- Children who are 5 years of age and below, since they tend to have a higher probability of nutritional deficiencies, including that of vitamin A
- Poverty, with insufficient resources to procure healthy foods leading to malnourished children and adults
- Underlying ailments like hepatic cirrhosis/liver cirrhosis, inflammatory bowel disease, pancreatitis, chronic diarrhoea, aside from very high alcohol consumption/alcoholism
The WHO (World Health Organization) categorises the onset and advancement of xerophthalmia into various stages, as listed:
- XN - Night blindness
- X1A - Conjunctival xerosis
- X1B - Bitot spots i.e. lesions on the cornea
- X2 - Corneal xerosis
- X3A - Corneal ulceration/keratomalacia, involving less than one-third of the cornea
- X3B - Corneal ulceration/keratomalacia, involving more than one-third of the cornea
- XS - Corneal scar due to xerophthalmia
- XF - Xerophthalmic fundus
The stages XS and XF indicate grave damage to the ocular tissues and invariably result in loss of vision.
In the initial stages, the indications of xerophthalmia are mild, such as:
As the disorder progresses, it presents with exacerbated signs such as:
- Tissue deposits on the cornea, known as Bitot’s spots, appearing as white spots on the eyes
- Ulcers and grave damage to the corneal tissues
- Softening, liquifying of corneal cells eventually resulting in blindness
The doctor first examines the eyes of the patient to check for signs of dry eyes and odd spots. They also enquire about the medical history, diet of the patient, besides any other symptoms of difficulties in vision they may be experiencing.
The healthcare provider also performs a blood test to gauge the levels of vitamin A and check if the patient has nutritional deficiencies. If the patient reports indications of night blindness, the medical expert begins the treatment with vitamin A therapy right away.
The primary mode of treatment for xerophthalmia, at any of the initial to middle stages of the disease, is vitamin A supplementation. The supplements are either prescribed to be taken orally or administered via injections. Furthermore, the physician prescribes antibiotics to prevent any eye infections from developing in the visual structures.
If damage to the cornea has already occurred, then the doctor advises the patient to also keep the area covered and protected, to seal it from the microbial pathogens, pollutants and detrimental toxins in the environment.
The best way to prevent xerophthalmia in children and adults is to ensure there is no vitamin A deficiency. This can be achieved by consuming a healthy balanced diet rich in vitamin A food sources like carrots, milk, fish eggs, dark green vegetables, yams, sweet potatoes.
In addition, for people on restrictive diets or facing limitations in obtaining a variety of vitamin A-rich foods, vitamin A supplements are advised to be taken by the doctor at the recommended dose, to ensure adequate nutrition and healthy vision.