Ординатура / Офтальмология / Английские материалы / Primary Care Ophthalmology_Palay, Krachmer_2005

FIGURE 3–35 Bacterial conjunctivitis with purulent discharge.

FIGURE 3–36 Follicular conjunctivitis. The smooth, rounded follicles with vascularization can be seen.

Major pathogenic agents of conjunctivitis are bacteria, viruses, Chlamydia, allergy, foreign bodies, and toxins, including medications. Each of these categories has characteristic features. Because conjunctivitis usually is self-limiting, laboratory workup typically is not warranted.

Bacterial conjunctivitis is characterized by a purulent discharge and probably is more common in children (Fig. 3–35). Simple bacterial conjunctivitis should be treated with broad-spectrum topical antibiotics. A common dosing schedule is every 2 hours while the patient is awake for the first day and then four times a day until a week of therapy is completed.

Viral conjunctivitis can be seen as an isolated condition or in combination with or following a viral upper respiratory tract infection. Discharge is mixed but mainly watery. With adequate magnification, the examiner may be able to see tiny rounded subepithelial follicular lesions (Fig. 3–36). Preauricular adenopathy also is a common finding.

Viral conjunctivitis can be extremely contagious. The patient should be considered contagious for 7 to 10 days after the onset of clinical signs. Children should be kept out of school and workers away from the work place where others might become infected. The examiner should use gloves and make certain that any furnishings or equipment exposed to the patient is cleaned.

56 CHAPTER 3 • The Red Eye

FIGURE 3–37 The patient had epidemic keratoconjunctivitis and demonstrates the very common findings of ecchymosis of the lids and subconjunctival hemorrhages.

FIGURE 3–38 Subepithelial infiltrates in epidemic keratoconjunctivitis, which are best seen using a broad oblique slit lamp beam.

Many different viruses can cause infection, but adenovirus is frequently implicated. Some types of adenovirus cause a combination of conjunctivitis, sore throat, and fever known as pharyngeal conjunctival fever. Other types cause an extremely contagious condition known as epidemic keratoconjunctivitis (EKC) (Fig. 3–37). At times, epidemics of this disorder have closed schools and physicians’ offices.

In most cases of EKC, subepithelial infiltrates may be observed by the end of the second week. These infiltrates can be seen only with the high magnification of the slit lamp (Fig. 3–38). Photophobia can be extreme and last for several weeks or longer.

Treatment of viral conjunctivitis should include careful cleansing of the eyes with a warm washcloth. The examiner cannot always be certain whether the conjunctivitis is viral or bacterial without expensive cultures. It is therefore reasonable to use topical broad-spectrum antibiotics, four times a day for a week. Artificial tears also can be soothing.

Conjunctivitis in the newborn is seen in four common settings. Toxic conjunctivitis is seen within the first 48 hours after the use of perinatal prophylactic antibiotics. Bacterial conjunctivitis usually manifests 2, 3, or 4 days after birth. Chlamydial conjunctivitis usually is seen 5 to 10 days after birth (Fig. 3–39A and B). Herpes simplex conjunctivitis manifests 6 to 14 days after birth.

In addition to inclusion conjunctivitis in the newborn, the chlamydial organism causes inclusion conjunctivitis in the adult (Fig. 3–40). Because chlamydial conjunctivitis is a sexually transmitted disease, transmission from the genitourinary tract of the patient and any sexual partner should be considered. Other serotypes of Chlamydia cause trachoma, a leading cause of blindness in underdeveloped countries.

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A B

FIGURE 3–39 A, The patient was a newborn with chlamydial conjunctivitis. B, Intracytoplasmic inclusion bodies (1) were found after scraping the palpebral (lid) conjunctiva followed by Giemsa staining.

FIGURE 3–40 Follicular conjunctivitis in an adult patient with chlamydial conjunctivitis.

The discharge in chlamydial conjunctivitis is mucopurulent. In the acute infection, it is very copious. Chlamydial conjunctivitis if not treated adequately becomes chronic, at which time the discharge is less profuse.

In acute infections, especially in the newborn, gram-positive inclusion bodies can be seen in the cytoplasm of conjunctival epithelial cells. If inclusion conjunctivitis is considered in the adult, a DNA Genprobe for Chlamydia laboratory test can be performed.

In the newborn, because chlamydial pneumonitis can occur along with the conjunctivitis, systemic erythromycin, 50 mg/kg per day in two to four divided doses is given for 2 weeks. In adult inclusion conjunctivitis, doxycycline, 100 mg two times a day for 3 weeks is used. If the patient is unable to take tetracyclines, erythromycin,

58 CHAPTER 3 • The Red Eye

FIGURE 3–41 Chemosis (edematous swelling of the conjunctiva) is seen in a patient with marked allergic conjunctivitis

(1).

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FIGURE 3–42 Vernal conjunctivitis. The characteristic vascular vegetative papillary lesions are evident.

250 mg four times a day is used instead. Infected sexual partners should receive treatment as well.

Allergic conjunctivitis is most common during the spring and fall allergy seasons (Fig. 3–41). It usually is associated with other mucous membrane reactions. Intense itching and a watery mucoid discharge are typical. In markedly acute cases, the conjunctiva can become extremely edematous.

Vernal conjunctivitis is an unusual form of allergic conjunctivitis. Flipping the upper lid reveals very large tufts of reactive tissue (Fig. 3–42). Vernal conjunctivitis requires referral of the patient to an ophthalmologist for management, because corneal complications are frequent (Fig. 3–43).

Another setting in which allergic conjunctivitis can be seen is that of topical drug allergy (Fig. 3–44). As in other allergic settings, itching is the key symptom. It is difficult to make the diagnosis of allergy without a complaint of itching. Because the drops also contact the lids and skin, reaction in the lids as well as conjunctiva is obvious.

FIGURE 3–43 Severe corneal scarring due to vernal blepharokeratoconjunctivitis.

FIGURE 3–44 Drug allergy resulted in the inflammation of the lids and conjunctiva seen in this eye.

Treatment of allergic conjunctivitis will depend on the particular setting in which it is seen. Cold compresses bring quick relief. In the case of seasonal allergic conjunctivitis, treatment with systemic antihistamines is important. Topical antihistamines are effective. Topical nonsteroidal anti-inflammatory agents are helpful because they bring rapid reduction of inflammation and relief of itching. Topical mast cell stabilizers can require days before benefit is realized, but when they are effective, they are safe drugs with great benefit. Because patients vary in their response to these antiinflammatory medications, trial of various combinations often is needed. In patients without systemic manifestations, topical medications alone are sufficient.

Another expression of conjunctivitis is that due to foreign material irritating the conjunctiva. A bicycle ride on a windy, dusty day can produce this form. On eversion of the upper lid (Fig. 3–45A and B), if no objects are found in the eye, topical anesthetic followed by irrigation with an eyewash will usually remove microscopic foreign bodies previously not visible.

Conjunctivitis also can be produced by eye rubbing. A previously normal, healthy eye can exhibit pathologic changes from eye rubbing that range from mild irritation to lid and corneal disease (Fig. 3–46). Chronic irritation from a contact lens against the palpebral conjunctiva, the conjunctiva on the back of the lid, can cause conjunctivitis. Mucous discharge deposits on the lens reduce vision and further irritate the eye.

62 CHAPTER 3 • The Red Eye

FIGURE 3–49 Pinguecula. These lesions are found at the 3 o’clock and 9 o’clock positions and are extremely common, especially in older patients.

FIGURE 3–50 Pterygium. These lesions are found in the horizontal meridian, most commonly nasally.

sis. If its appearance or location is unusual, the patient should be referred for ophthalmologic management.

Corneal Epithelial Injury

A scratch to the corneal epithelium produces a corneal abrasion with severe pain (Fig. 3–51). A fluorescein drop used with a cobalt blue light shows the green-staining lesion. Instillation of antibiotic ointment and application of a patch worn until the next day for comfort usually constitute adequate treatment. Instillation of antibiotic drops without patching also is acceptable and is supported by recent studies. A cold compress can be used to relieve discomfort, with addition of an oral analgesic if pain is extreme. Use of broad-spectrum antibiotic drops should be continued until the lesion has healed. With persistent pain, the patient should be referred for evaluation to determine whether infection, iritis, or some other reason for the continued discomfort is present. After healing, the corneal epithelium can later break down; the resultant lesion is termed a recurrent erosion (Fig. 3–52).

64 CHAPTER 3 • The Red Eye

FIGURE 3–53 A small superficial corneal foreign body.

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FIGURE 3–54 A rust ring (1) that developed following implantation of an iron corneal foreign body.

FIGURE 3–55 Eyestrain is a very common cause of a mildly red eye.