Conjunctivitis: what it is, types, causes, symptoms and treatments

Conjunctivitis: what it is, types, causes, symptoms and treatments

Conjunctivitis is an inflammation of the conjunctiva, the tissue that covers the inner surface of the eyelids and the anterior surface of the eyeball. The conjunctiva performs the function of defending the eye from microorganisms and protecting it from foreign substances: under normal conditions it is lubricated by the secretion emitted by the lacrimal glands.

Among the pathologies affecting the eye, conjunctivitis is among the most common. It can occur in an acute or chronic form, it can affect only one eye or both.

The cause of this eye disease can be bacterial, viral or caused by other microorganisms. In fact, it can be the allergic response to some elements such as pollen, dust, animal hair but also drugs, cosmetics or it can be caused by excessive exposure to sunlight.

What is conjunctivitis

Conjunctivitis is an inflammation of the conjunctiva, a thin transparent membrane that covers the inner surface of the eyelids and the white part of the eye. It can affect one or both eyes and is a fairly common condition.

The causes are varied and include viral, bacterial or fungal infections, allergies, chemical irritations or reactions to irritants such as smoke, dust or chemicals. Some forms of conjunctivitis can also be very contagious.

The common symptoms of conjunctivitis, on the other hand, are quite recognizable as:

  • Red and swollen eyes.
  • Sensation of itching or burning in the eyes.
  • Tearing.
  • Eye discharge (pus or mucus).
  • Sensitivity to light.
  • Blurred vision.

Diagnosis is based on an eye exam and assessment of symptoms, while treatment depends on the underlying cause.

For example, if the conjunctivitis is bacterial in origin, antibiotics in the form of eye drops or ointments may help. In the case of viral conjunctivitis, on the other hand, there are no specific drugs and they are usually dealt with with natural remedies such as the use of cold or warm patches on the eyes and keeping the eyelids clean.

Also, to prevent the spread of pink eye, it’s important to take hygiene measures, such as washing your hands regularly and not sharing towels or personal items with other people.

If you are interested in the topic, discover our in-depth study on eye diseases.

Conjunctivitis: symptoms

The symptoms of conjunctivitis are quite similar in all its types and can be more or less serious. A lot depends, in fact, on the triggering cause. The most common include:

  • Red or hyperaemia eyes: The eye may appear red or swollen from inflammation of the blood vessels in the conjunctiva.
  • Itching: it is a typical symptom, especially if it is of allergic origin.
  • Burning eyes: it can be more or less intense, depending on the severity of the inflammation.
  • Tearing: Producing more tears is a defense mechanism of the eye, also to relieve discomfort.
  • Sensation of a foreign body in the eye (like “grit”).
  • Eye discharge: Depending on the type of conjunctivitis, eye discharge may be clear, yellow, green, or sometimes accompanied by pus.
  • Sensitivity to light: photophobia can occur especially when you are exposed to bright lights.
  • Blurred vision: In some cases, conjunctivitis can cause a temporary decrease in visual clarity or a feeling of blurred vision.
  • Swelling and cloudy or blurred vision.

Conjunctivitis: the causes

The causes of conjunctivitis can be of different nature. Inflammation of the conjunctiva can depend on:

  • Bacteria or virus. Some bacteria can cause infections of the conjunctiva, such as Staphylococcus aureus, Streptococcus pneumoniae or Haemophilus influenzae. These infections are often characterized by a purulent discharge and may require antibiotic treatment. Viral ones are also widespread, such as the flu virus, herpes simplex, etc.
  • Mushrooms. They are less common and the most common fungi are Candida albicans and Aspergillus.
  • Allergies to substances such as pollen, dust, animal dander or mold. This form of conjunctivitis is often accompanied by allergic symptoms such as itchy, red, watery eyes.
  • Chemical irritants such as smoke, air pollutants, chlorine, cleaning products, or inappropriate eye drops can cause irritation and inflammation of the conjunctiva.
  • Eye trauma or injury, such as scratches, abrasions, or foreign objects that can lead to traumatic conjunctivitis.

Complications of conjunctivitis

If well treated, it is a disease that resolves quickly. In some rare cases, the following complications may develop:

  • Otitis media (an acute or chronic inflammation of the cavity behind the eardrum, also called the “middle ear”) with conjunctival haemorrhage (bleeding from the eye).
  • Formation of small vesicles along the eyelid margin (typical lesions induced by herpes viruses).
  • Blurred vision.
  • Keratitis (inflammation of the cornea).
  • Meningitis.
  • Septicemia due to the persistent presence in the blood of bacteria such as streptococci, staphylococci, pneumococci and meningococci.

In infants, the infectious form can cause a serious eye infection which, if not treated properly, could cause permanent vision damage.

Contact your pediatrician immediately if you observe tearing or abnormal secretions.

Various types of conjunctivitis

Bacterial conjunctivitis is the most common form: it appears to make up about half of all types of acute conjunctivitis. In any case, there are different types of conjunctivitis: here are the most common.

Allergic conjunctivitis

Allergic conjunctivitis affects approximately 10% of the world population. It can be of two types: seasonal or chronic.

If it is seasonal, it is important to go to the ophthalmologist in time so that he can prescribe a suitable prophylaxis able to counteract the acute symptoms.

The main types of allergic conjunctivitis are:

  • Seasonal allergic conjunctivitis: the characteristic complaints occur at certain times of the year.
  • Perennial allergic conjunctivitis: the characteristic disturbances occur throughout the year.
  • Contact dermatoconjunctivitis.

In these cases, especially in the case of chronic conjunctivitis, it is also advisable to consult an allergist who could prescribe a suitable vaccine.

Bacterial conjunctivitis

Bacterial conjunctivitis is an eye infection caused by bacteria. The most common cause is streptococcus, specifically Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis.

Unlike allergic conjunctivitis, the bacterial form does not manifest itself with intense itching and tearing is not so abundant. However, the symptoms include:

  • eye redness.
  • Swollen eyelids.
  • Yellow or green eye discharge.
  • Burning.
  • Sensation of sand or foreign body in the eye.
  • Small crusts on the eyelids upon waking.

Viral conjunctivitis

Viral conjunctivitis is mainly caused by viruses such as adenoviruses or herpesviruses. When it is viral, the problem can be associated with: fever, cough, sore throat, swelling of the lymphatic glands.

The secretion is fluid, almost never purulent unless a bacterial infection superimposes.

“Dry eye” conjunctivitis

It occurs as a result of hormonal changes, the intake of particular drugs or in old age.

The cause is a low production of tears, the natural eye cleanser: this makes the eye drier and therefore more vulnerable to inflammation and possible corneal ulceration.

Actinic conjunctivitis

It is caused by sunlight or other forms of radiation.

Therefore, to avoid it, it is advisable to use sunglasses equipped with filters for ultraviolet rays. Due to these characteristics, actinic is more frequently contracted by the sea, after exposure to tanning lamps and on the snow.

Contact and papillary conjunctivitis

It is an inflammation of the conjunctiva and skin (skin) of the eyelids caused by an allergic reaction to products or substances such as:

  • eye drops.
  • Cosmetics.
  • soaps.

The papillary one, on the other hand, indicates the allergic reaction of the eyelid conjunctiva to the contact lens. Symptoms resolve simply by avoiding its use for some time.

The papillary can also occur in wearers of ocular prostheses and in people with permanent sutures for keratoplasty or cataract operations. The symptoms of this type are: discharge and the need to quickly remove the lens.

In the neglected forms, the itching is very strong and is associated with increased mucous secretion and a foreign body sensation. The suspension of the lenses makes the symptoms regress, but the papillary hypertrophy can persist even for years.

In case of conjunctivitis it is necessary to suspend the use of contact lenses until complete healing.

If a viral form is diagnosed, it is important to throw away the old lenses, including the container, to avoid the risk of re-infecting them.

Conjunctivitis in children

Conjunctivitis in children is quite common and can be caused by a variety of reasons, including bacterial, viral or allergic infections. Symptoms of conjunctivitis in children may include: red and swollen eyes, itching or burning, sensation of something in the eye, crusting of the eyelids.

In these cases it is important to consult a pediatrician or an ophthalmologist for a correct evaluation and diagnosis.

Treatment of conjunctivitis in children depends on the underlying cause. In general it is useful:

  • Clean the eyes with sterile saline solution or cooled boiled water to gently cleanse the baby’s eyes with…