In xerophthalmia, the cornea and conjunctiva of the eye dry out. Vitamin A deficiency is usually the cause of the condition, which is most common in developing countries. Treatment is by vitamin A substitution or by creating an artificial tear film.
What is xerophthalmia?
The cornea is the most anterior, highly curved and transparent portion of the eyeball in front of the pupil. The transparency of the cornea is imperative for ocular function. The homogeneously structured surface is covered by a tear film. Conjunctiva, or conjunctiva, is also an important component of the eyes. The mucosa-like tissue layer connects the eyeball with the eyelids. Both of these elements of the eye can be affected by disease. One disease that affects the cornea and conjunctiva at the same time is xerophthalmia. This is a dehydration condition that often results in blindness. The disease occurs most frequently in developing countries. The age group mainly affected is infants. For this reason, xerophthalmia is also known as childhood blindness. In the western industrialized nations, dry eye syndrome occurs from time to time. This phenomenon is to be distinguished from xerophthalmia in the narrow definition, although in the literature sometimes any type of eye dryness is called xerophthalmia.
Causes
Xerophthalmia can have a variety of causes in the broader definition. In the narrower definition, hypovitaminosis is the causative factor. Without vitamin A, the conjunctiva and cornea may dry out. Such deficiencies are caused in most cases by improper diet or malnutrition. Severe vitamin A deficiency dissolves the collagen matrix, softens the cornea and irreversibly destroys the eye. Xerophthalmia is the most common cause of blindness to date due to the malnutrition situation in developing countries. South and East Asia as well as African countries, Latin America and the Middle East are particularly affected. In the broader definition, xerophthalmia can also be caused by incomplete closure of the eyelids in the sense of lagophthalmos, although not all described changes occur. In addition, lacrimal secretion disorders can cause similar symptoms, for example, in the context of Sjögren’s syndrome.
Symptoms, complaints, and signs
Symptoms of xerophthalmia depend on the primary cause in each individual case. In vitamin A deficiency, less light-sensitive pigment is produced in the rods. Incipient xerophthalmia may therefore manifest as night blindness in the context of vitamin A deficiency. In the conjunctiva, epithelial cells also keratinize. In addition to this keratinization, dull white spots appear on the conjunctiva. The cornea becomes dry and rough at the same time. Vessels form on the cornea. Vision is impaired due to the change in transparency. In xerophthalmia with a cause other than vitamin deficiency, there is no deficiency of photosensitive pigment. However, the conjunctiva and cornea dry out in all cases. In addition, many patients complain of severe itching in the eye. Furthermore, the phenomenon is associated with a subjectively felt foreign body sensation. With a progressive drying of the eyes the protection of the antibacterial tear film is missing, so that with the time inflammations such as the conjunctivitis or keratitis occur. If left untreated, secondary complications such as keratomalacia occur, which can cause irreversible vision loss.
Diagnosis and disease progression
Diagnosis of xerophthalmia is primarily anamnetic and vision diagnostic. The symptom is attributed to a cause during the diagnostic process. In the western countries the secretion disorder of the lacrimal fluid corresponds to the most frequent cause. Secretion disorders are detected by means of the Schirmer test. Strips of blotting paper in the conjunctival sac absorb the tear fluid. In the case of deficiency symptoms, the inserted paper remains dry. Vitamin A deficiency can be clarified by [blood test|blood analysis]]. The prognosis for patients with xerophthalmia depends on the primary cause and its treatability. In addition, the stage of xerophthalmia plays an important role in the prognosis.
Complications
In many cases, the symptoms of xerophthalmia are not particularly clear, so early diagnosis and treatment cannot be initiated for this condition. Affected individuals primarily suffer from night blindness, which can have a very negative impact on everyday life and quality of life. The cornea of the affected person drips and there is a strong sensitivity to light and also a permanent itching in the eye. Due to the strong itching, the eyes often swell up. Also a foreign body feeling occurs in the eye by the Xerophthalmie and can impair the sight of the concerning negatively. Furthermore, the eye becomes inflamed and infected if the disease is not treated. Irreversible limitation or reduction of vision can also be a disease-related consequence. Treatment of xerophthalmia is usually without complications and can limit the symptoms relatively well. Those affected depend on taking supplements and using eye drops. In most cases, this limits all symptoms. The life expectancy of the affected person is not negatively affected by xerophthalmia.
When should you see a doctor?
People who prefer a one-sided diet are well advised to initiate a follow-up visit to a doctor at regular intervals. The general state of health should be checked so that appropriate action can be taken in the event of abnormalities. An unbalanced diet often results in a deficiency of vitamins or other important and vital nutrients, which must be recognized and changed in good time. If a loss of vision becomes apparent, consultation with a physician is always necessary. Of concern is blurred vision, hypersensitivity to the effects of light or night blindness. In the case of these complaints, a visit to the doctor is necessary so that a clarification of the cause can be initiated. A strong itching of the eye is also to be understood as a warning signal of the organism. If there is redness or open sores in the area of the eyes or eyelids, action is required. If the disease progresses unfavorably or without medical treatment, irreversible damage to vision may occur. Failure to cooperate with a physician may result in blindness. Therefore, it is advisable to consult a doctor at the first changes or abnormalities of vision. An unusually dry eye or keratinization should be examined and treated as soon as possible. In addition, in the case of a general malaise or other diffuse complaints in the organism, it is recommended to consult a doctor.
Treatment and therapy
The therapy of xerophthalmia depends on the primary cause. Causative treatment is mandatory, such as intravascular vitamin substitution in the case of causative vitamin A deficiency. As symptomatic treatment options tear fluid treatments are available. The missing tear film is compensated by replacement fluid. If functional impairment of the meibomian glands is the cause of xerophthalmia, eye drops containing anakinra are given. The human interleukin antagonist is known as an active substance from the treatment of rheumatoid arthritis and seems to be able to alleviate xerophthalmia as well. In Germany, however, the approval of the eye drops is still pending. In addition, antibiotic eye drops are used off-label. These drops usually work with the active ingredient azithromycin and prevent complications of bacterial infestation. Antibiotics act directly on the epithelia within the meibomian glands. This not only prevents bacterial infestation. It also stimulates the formation of an oily secretion that can keep the eyes permanently moist. Inflammations caused by complications are treated with high doses of antibiotics in order to prevent late complications caused by inflammation and irreversible damage to the eyes. In principle, xerophthalmia is a relatively well controllable disease in industrialized countries, regardless of the cause, and usually does not leave irreversible damage. In developing countries, however, it still often leads to blindness due to inadequate medical and nutritional care.
Prevention
The vitamin A deficiency-related form of xerophthalmia can be prevented by a balanced diet and thus balanced vitamin A intake. Eyelid closure-related and other forms cannot be fully prevented. Therefore, anyone who notices a foreign body sensation in the eye should always consult an ophthalmologist. Early diagnosis of xerophthalmia prevents irreversible damage.
Follow-up
In most cases, only very limited measures of direct aftercare are available to the affected person with xerophthalmia. First and foremost, sufferers of this condition should see a doctor early to prevent the onset of other symptoms and complications. In the worst case, complete blindness of the affected person can occur if no timely treatment is given, so a doctor should be contacted at the first signs and symptoms of this disease. There is no possibility of self-healing. Sufferers of xerophthalmia are usually dependent on the use of eye drops. This can limit and relieve most of the symptoms. As a rule, the affected person should pay attention to a correct dosage and also to a regular use of the eye drops. If there are any uncertainties, questions or side effects, it is advisable to consult a doctor first. Regular check-ups by an ophthalmologist are still very important even after successful treatment. In most cases, xerophthalmia does not reduce the patient’s life expectancy.
What you can do yourself
Xerophthalmia is often based on a nutritional deficiency of vitamin A. If the affected person is outside a developing country, he should review and optimize his diet. The intake of individual foods per meal should be controlled and must be adapted to the needs of the organism. Vitamin A is found in foods such as carrots, spinach, red peppers, apricots, broccoli or tomatoes. Therefore, in order to alleviate the existing symptoms, care should be taken to consume the above-mentioned foods in such a way that the daily requirement of vitamin A is sufficiently covered. In addition, the eyes should be adequately protected from adverse effects. Strain or overexertion of the eyes should be avoided. Everyday tasks should be carried out under optimal lighting conditions so that no complications are triggered. If symptoms of fatigue occur, rest periods should be taken. The organism needs time to regenerate so that no long-term damage to vision occurs. If eye dryness is present, prescribed drops must be used. Artificial intake of water or similar fluids is not recommended. In some cases, increasing the frequency of eyelid blinking may help relieve symptoms. Therefore, especially in dry environmental conditions or in a polluted air, the mechanism of eyelid blinking should be increased independently.
