The red painful eye

Acute red painful eyes are due to: (1) conjunctivitis (much the most common cause at any age). There are two particularly important forms of conjunctivitis in different age groups. (1a) Ophthalmia neonatorum in newborn babies. (1b) The conjunctivitis associated with recent measles in children between the ages of 6 months and 6 years. There are also some important, but less common causes of an acute red eye: (2) A corneal ulcer. (3) Acute iritis. (4) Acute glaucoma. (5) Trauma is another cause, but the diagnosis is usually obvious from the history (Chapter 60).

The problem in a busy clinic is that conjunctivitis is so much more common than the rarer causes of a red eye, that these are easily missed. So your first task in managing red eyes is to make sure that these rarer causes are recognized. Twenty patients may have conjunctivitis, and the twenty-first a corneal ulcer, or acute glaucoma. A patient's history, his visual acuity, and the examination of his eye with a torch should enable you to decide which he has.

Conjunctivitis can be bacterial, viral, allergic, or chemical. Bacterial conjunctivitis is common in the developing world, and may be mild, or so severe that a patient's conjunctiva pours out pus, and his lids swell so much that he cannot open his eyes. Neglected bacterial conjunctivitis may be followed by a corneal ulcer and a corneal scar, or by perforation and endophthalmitis. Bacterial conjunctivitis needs an antibiotic. Viral conjunctivitis usually resolves spontaneously without one, if the cornea is not involved.

Besides infecting a patient's conjunctiva, bacteria can infect his lids (blepharitis), or his cornea, where they can cause: (1) Changes in the stroma (keratitis and sometimes a corneal abscess). (2) A corneal ulcer, which is a loss of surface epithelium. The danger of a corneal ulcer is that infection may spread inside his eye as an endophthalmitis, which may blind him.

A corneal ulcer may be due to: (1) Bacteria. (2) Herpes simplex virus. (3) Fungi. (4) Other conditions such as leprosy, causing lagophthalmos and exposing his cornea (30.3). Bacterial corneal ulceration can follow even a minor injury which damages the epithelium, or it can be spontaneous. Corneal ulcers are most easily seen when they are stained with fluorescein, which is why this is so useful.

When bacteria enter an eye through a corneal ulcer the first place they get to is the anterior chamber. If pus gathers here, and the patient stands upright, it falls to the bottom, with a straight upper fluid level called a hypopyon, as shown in C, Fig. 24-7.

Endophthalmitis may be the result of: (1) A corneal ulcer, especially a bacterial one. (2) A perforating injury of his cornea or sclera, especially if a foreign body has been left inside his eye (60.9), or if a wound is neglected (60.4). Once bacteria have entered his eye, the chance of total blindness is high. If you see him early, when the infection is fairly localized, he may retain some useful vision; but if you see him late, the best you can do is to control infection, because his eye will be blind. If you cannot control it, you will have to eviscerate his eye (24.14).

RED PAINFUL EYES [s7]AND OTHER EYE INFECTIONS For the general method see Section 24.1. Acute iritis (24.5) and acute glaucoma (24.6) are described here as part of the differential diagnosis of a red eye, but are dealt with more fully later. Make sure you examine the patient in a good light.

THE DIAGNOSIS. If he has conjunctivitis, his discomfort or pain varies from mild to severe: (1) Both his eyes are usually involved. (2) His visual acuity is normally good. (3) He usually has a purulent discharge. (4) His conjunctivae are red, especially in his fornices. (4) His cornea is clear and does not stain with fluorescein (unless his conjunctivitis has caused a corneal ulcer). (5) His pupils are normal. (6) The tension in his globe is normal.

THE DIFFERENTIAL DIAGNOSIS OF CONJUNCTIVITIS. Distinguish particularly between the redness of conjunctivitis, which is typically maximal at the periphery, but is often uniform everywhere (very common), and redness which is most marked at his corneoscleral junction (ciliary injection, less common).

CAUTION ! Look for mucopus in his inferior fornix[md]it is always present in bacterial conjunctivitis; hesitate to diagnose conjunctivitis if you don't find any.

Conjunctivitis is usually bilateral: its important differential diagnoses are usually unilateral:

Suggesting acute iritis[md]one (sometimes two) moderately painful red eye(s) with no discharge. His pain is often only mild, and he may complain of headache. Reduction in visual acuity, which may be only mild. Ciliary hyperaemia. A clear cornea. A small constricted pupil, which becomes irregular when you dilate it, due to posterior synechiae (adhesions). Look for an inflammatory exudate in his anterior chamber, preferably with a slit lamp: his aqueous is not as clear as it should be. The beam from the lamp shows a flare, like a beam of light shining across a dusty room. You may also see little lumps of cells (keratic precipitates or KP) sticking to the back of his cornea, and posterior synechiae between his iris and the front of his lens. The inflammatory cells in his anterior chamber may form a sterile hypopyon. His IOP (intraocular pressure) may be increased due to secondary glaucoma (24.6).

Suggesting acute angle closure glaucoma[md]one (seldom two) very painful red eye(s) with severe unilateral headache, and slight watering. Severely impaired visual acuity, often down to hand movements or perception of light only, with haloes, and sometimes even blindness. Ciliary hyperaemia (mild in the early stages). A hazy cornea (due to raised IOP) without its normal lustre. A shallow anterior chamber; this is best seen by shining a torch from the side. A vertically oval dilated pupil which does not react to light. A raised IOP (24.1).

Suggesting a corneal ulcer[md]one severely painful red eye with reduced visual acuity (if the ulcer is central), redness most marked round the limbus, photophobia, swollen eyelids, and watering. Look for a grey-white spot (the ulcer) on his cornea, which stains with fluorescein. If it is not obvious, look for a defect in the smooth surface of his cornea in the reflection from a focused light. If his ulcer is central, hyperaemia is equal all round his limbus. If it is near the edge, hyperaemia is more marked there. If his infection is severe, pus cells sediment at the bottom of his anterior chamber, with a fluid level (hypopyon). His pupil is usually regular. For treatment see below.

Suggesting a foreign body. The signs of an abrasion (60.4), and a foreign body (60.9), are similar to those of a corneal ulcer[md]unilateral pain, photophobia, a watery discharge, somtimes impaired vision, and ciliary hyperaemia, which may be localized to the region near the lesion. See also Section 60.4.

Fig. 24-6 EXAMINING A BABY'S EYES. Sit him on his mother's lap and hold his head between your knees.

ACUTE INFECTIVE CONJUNCTIVITIS TREATMENT. Clean his eyes with a cotton swab and saline. Instil chloramphenicol eye drops or ointment hourly in severe infections, and 3 hourly in less severe ones. Or use tetracycline ointment, with or without polymyxin and bacitracin. An eye ointment at night will prevent his lids sticking together. Continue treatment for two days after symptoms have resolved. Allow the exudate to escape, clean his eyes with a clean cloth and water, and don't pad them.

CAUTION ! If his conjunctivitis is severe, watch carefully for a corneal ulcer, and if necessary examine his cornea with fluorescein.

If his corneae are not clear and his visual acuity is poor, he has a corneal ulcer (see below) and his sight is in danger.

CORNEAL ULCER TREATMENT is an emergency. Start aggressive treatment with antibiotics urgently. Admit him. He may be more comfortable with a pad or shield (24.1).

If his ulcer is severe, and particularly if he has hypopyon, give him a subconjunctival injection (24.1) of gentamicin 40 mg, or chloramphenicol 100 mg. Also, apply chloramphenicol drops, or tetracycline eye ointment hourly. Also give him systemic chloramphenicol (24.1, 2.9).

If his ulcer is not so severe, and he has no hypopyon, hourly conjunctival antibiotics and atropine ointment 3 times daily may be adequate.

Also, with any corneal ulcer, provided it has not already perforated, give him atropine eye ointment 2 or 3 times a day to keep his pupil dilated. This will prevent adhesions forming between his iris and his lens (posterior synechiae). Advise warm soaks (24.1). If there is any suspicion that he may be short of vitamin A, give it (see below). Complications include: (1) Diffuse scarring of his cornea (24.4). (2) A dense white scar (leucoma, 24.4). (3) Perforation of his cornea, with adherence of his iris, and perhaps staphyloma (an opaque protrusion of his cornea). (4) Endophthalmitis.

If his corneal ulcer is very severe, so that his whole anterior chamber fills with pus, he has endopthalmitis.

If his corneal ulcer has proceeded to the point where it has weakened, softened, and distorted his globe (pthisis bulbi) you will have to eviscerate it (24.14).

ENDOPHTHALMITIS [s7](panophthalmitis) His anterior chamber is full of pus. Subconjunctival and parenteral antibiotics (24.1) are essential, but it usually too late for them to be successful, because the inside of his eye has become an abscess.

If his endophthalmitis is early, with some hope of vision, refer him urgently if you can. If not, try to control infection and minimize pain. Give him subconjunctival and parenteral chloramphenicol for 5 to 7 days. His infection may settle.

If his endophthalmitis is due to a foreign body in his eye, remove it. It is usually superficial, so that you can remove it through the wound by which it entered, which is usually in his cornea, even if this has to be enlarged (60.9). Remove any prolapsing iris, and suture his cornea (60-6). Continue subconjunctival and parenteral antibiotics. Remove the sutures at 7 days.

If he presents late, with no hope of vision and an anterior chamber full of pus, and shows no improvement in 48 hours, eviscerate his eye (24.14). The chances of sympathetic ophthalmia are negligible, so this is not a determining factor in deciding to remove it (60.10).

DIFFICULTIES [s7]WITH RED PAINFUL EYES If a NEONATE has RED SWOLLEN CONJUNCTIVAE with a PURULENT DISCHARGE, a few days after birth, he has OPHTHALMIA NEONATORUM, which may be gonococcal or chlamydial. His cornea is usually clear, but may have an ulcer. This is an acute emergency, which may blind him. Clean away the pus with a swab and water, put tetracycline ointment into his eyes every hour. Give him penicillin, for example crystalline penicillin 30 mg/kg/day in 4 divided doses intramuscularly. Or, less satisfactorily, give him procaine penicillin forte 0.5 ml (30 mg) daily. Continue penicillin for 5 days.

If his conjunctivitis is very severe, and especially if he has a corneal ulcer, instil chloramphenicol eye drops every minute for one hour, every hour for one day, and then 3- hourly until he is better, and give him penicillin as above.

If he has an ACUTE RED EYE BETWEEN THE AGES OF 6 MONTHS AND 6 YEARS, the important condition is the combination of malnutrition, vitamin A deficiency, and recent measles. Look for: (1) Night blindness (inability to see in dim light). (2) Bitot's spots (white foamy spots on his lateral conjunctiva). (3) Xerosis (dryness of his conjunctiva with inability to produce tears, or a dry hazy cornea). (4) Keratomalacia (corneal ulceration, softening of his cornea). Give any child with any of these signs vitamin A 200,000 iu by mouth immediately, again after 24 hours, and again after 1 week. Also, give him a topical antibiotic such as tetracycline 1% 3 times daily. If his cornea is ulcerated, give him atropine eye ointment 1% once daily, and an eye pad. Improve his nutrition, and encourage his mother to give him plenty of dark green leafy vegetables.

If he has a CHRONIC LOW-GRADE CONJUNCTIVITIS with yellow-grey dots (follicles) under his upper eyelid, and he comes from an endemic area, he almost certainly has TRACHOMA caused by Chlamydia trachomatis. This goes through three stages described in Section 24.13; the important one to recognize is the second. During the acute stage, make sure he puts tetracycline eye ointment 1% or 3% into his eyes twice a day for six weeks. If his trachoma is severe, also give him a 14-day course of a sulphonamide or tetracycline.

Teach him to wash his face and hands well several times daily, and to avoid rubbing his eyes. Explain that his disease is due to the entry of dirt, often from flies. Apply tetracycline eye ointment to any case of acute red eyes, particularly when these occur as epidemics of conjunctivitis.

If LARGE GELATINOUS VEGETATIONS have formed on his upper tarsal conjunctiva, and look like cobblestones, or on the bulbar conjunctiva surrounding his limbus, suspect ALLERGIC CONJUNCTIVITIS. This is common in children and young adults. Their eyes are very itchy and water much. Suppress the inflammation with antihistamine drops or a very weak steroid. Beware of steroid glaucoma (24.5, 24.6D), because steroids, once started, may be needed for many years.

If he complains of PAIN AND WATERING WITHOUT ANY HISTORY OF A FOREIGN BODY, consider the possibility of a DENDRITIC ULCER. Stain his cornea with fluorescein and look for a branching irregular ulcer, which may also resemble the outline of an amoeba, or a country on a map. This is due to infection with the herpes simplex virus. He may think (wrongly) that ''something has got into his eye''. Dendritic ulcers occur all over the world, especially after fevers, particularly measles, malaria, and meningitis. In the industrial world they are now the most common and most damaging form of corneal ulcer; they commonly recur, and treatment is difficult. Refer him.

If you cannot refer him, if possible give him an antiviral agent: idoxuridine ointment ([mu]5 daily), trifluorothymidine drops (hourly), or acylovir ointment ([mu]5 daily). If his lesion is severe, combine this with mechanical removal of the epithelium containing the virus. Apply a topical anaesthetic, and stain his cornea with fluorescein. Using a loupe, a good light, and a ball of cotton wool on the end of an applicator, gently scrub the surface of his cornea in the region of the ulcer to remove its epithelium. A chronic stromal keratitis with corneal scarring and blindness can complicate herpetic eye diease.

CAUTION ! Never apply steroids, because these may spread the infection to the stroma of his cornea, and make his condition worse.

If a CHEMICAL has got into his eye, his conjunctiva is intensely red (more so than in infective conjunctivitis), his cornea may be opaque (from keratitis or an ulcer), and his vision impaired. Unlike infective conjunctivitis, mucopus is absent. He may admit to having used traditional medicine for a painful eye, which has made it worse. If the chemical is still present, wash it out with much water. Give him an analgesic, and shield his eye. Instil an antibiotic ointment; its vaselene base will be soothing, and the antibiotic may prevent secondary infection.

If he has an acutely inflamed and oedematous lid or face, with a BLACK SLOUGH, and surrounding brawny oedema, and hides are used in the district, consider the possibility of ANTHRAX. His eyelid may be completely destroyed, but his eye is normal. Give him high doses of penicillin and sulphonamides. Anthrax responds rapidly to penicillin. Later, if necessary, toilet the slough and graft the raw area. If you leave raw lids ungrafted, severe scarring and a scar-induced ectropion may follow.

Fig. 24-7 THE IRIS AND THE CORNEA. A, a vertical section of the eye to show the flow pattern of the aqueous. B, iris bomb[ac]e[md]the iris is adherent to the lens all round and is bulging forwards. C, an acute bacterial corneal ulcer with a hypopyon. D, acute iridocyclitis. The pupil is small and irregular, because posterior synechiae have formed. E, a dendritic ulcer of the cornea, the result of herpes simplex infection.

1, some KP on the back of the cornea. 2, a posterior synechia (adhesion between the lens and the cornea). 3, a hypopyon. After Parr, John, ''Introduction to Ophthalmology', (2nd edn 1982). OUP, with kind permission.