Trachoma is a bacterial infection of the eyes caused by Chlamydia trachomatis. The infection leads to scarring of the inner surface of the eyelids and erosion of the corneal surface, which eventually leads to blindness. Trachoma is one of the leading causes of blindness worldwide today. The bacteria are transmitted via direct or indirect contact. Contact with the affected person's eye or nose are the main ways the infection is spread. Closed living spaces and poor sanitation increase the spread of the disease.
The causative agent of trachoma, Chlamydia trachomatis, is transmitted from infected to uninfected individuals in numerous ways: direct eye to eye spread during close contact, hand-eye contact, indirect spread on fomites, and transmission by eye-seeking flies.[1] Crowded living conditions play a major role in promoting the spread of the disease.[2] Trachoma is frequently found to cluster within endemic regions.
Trachoma is considered to be the third leading cause of blindness worldwide after cataract and glaucoma.[3] Almost 8 million people are either blind or have severe visual impairment due to trachoma according to some estimates.[4] Africa, some regions of the Middle East, the Indian Subcontinent, Southeast Asia, and South America show the highest prevalence today.[5] North America and Europe showed a significant reduction in the disease prevalence due to general improvement in living standards, rather than specific interventions.[1]
Trachoma is a childhood disease, and pre-school children are most commonly affected as compared to adults.[6][7] With increasing age, however, the prevalence of scarring increases as opposed to the signs of active infection. Studies have shown that in some areas, women are more frequently affected by the disease complications than men.[8]
Trachoma is associated mainly with infection by serovars A, B, Ba, and C of Chlamydia trachomatis. Serovars D-K are conventionally associated with adult inclusion conjunctivitis. Other species of the Chlamydiaceae family, such as Chlamydophilia psittaci and Chlamydophila pneumoniae, have also been implicated.
Trachoma infection occurs as an initial 'active' inflammatory stage, which is more common in pre-school children. This may be mild and may only result in trachomatous conjunctivitis (follicular/papillary). Intense cases are characterized by the presence of papillary hypertrophy.
Recurrent infection, however, elicits a chronic immune response. The presence of intermittent chlamydial antigens provokes this reaction. It is a cell-mediated delayed hypersensitivity (Type 4) response. This repeated insult leads to scarring and other forms of permanent damage. This is the chronic 'cicatricial' stage and most commonly occurs in middle age. Most of the scarring in this stage is prominent on the upper tarsal plate. This scar tissue contracts leading to in-turning of the lid, causing entropion, and this entropion eventually leads to trichiasis. Entropion is the most common cause of trichiasis in trachoma patients. Trichiasis, however, may also result from aberrant lashes or metaplastic lashes in rare cases. Ultimately, blinding corneal opacification can develop.
In children, active trachoma is common. The classic findings include a hyperplastic conjunctival epithelium, and widespread inflammatory infiltrates such as B and T lymphocytes, neutrophils, macrophages, and plasma cells.[9] A generalized increase in collagen types 1, 3, and 4 is seen on staining for collagen subtypes. Studies have also revealed the deposition of new type 5 fibers.[10] In adults with scarring, however, the conjunctival epithelium is atrophic, and goblet cells are lost.[11] A thick scar of type 5 collagen replaces the loose subepithelial stroma. These newer fibers get attached to the tarsal plate tightly. This eventually leads to distortion. Conjunctival inflammation is often observed.
History:
Patients with trachoma will usually present with redness of the eyes, itching and irritation of the eyes and eyelids, discharge from the eyes, swelling of the eyelids, eye pain, and photophobia. It is important to determine the duration of the symptoms. A history of travel to endemic areas (e.g., North Africa, Middle East, India) should be obtained. Concomitant vaginitis, cervicitis, or urethritis should be ruled out if the patient is sexually active.
Physical:
Active Trachoma
Cicatricial Trachoma
The diagnosis of trachoma relies chiefly on history and the clinical signs, as seen on slit-lamp examination. While many diagnostic tests have been developed to detect the organism, there exists no 'gold standard' investigation.[12][13] Some of the tests currently used are:
The SAFE strategy recommended by WHO encompasses surgery for trichiasis, antibiotics, facial hygiene, and environmental improvement.
Management of Trichiasis and Cicatricial Entropion:
Trachoma is the most common infectious cause of blindness worldwide. Conjunctival scarring with ensuing trichiasis and entropion result in corneal scarring and eventual blindness. The proper management of trichiasis and cicatricial entropion in trachoma is vital to prevent visual disability.
Treatment of Lashes: There is a movement to teach simple procedures to ancillary medical team members in areas where this disease is endemic so that early intervention may be instituted and corneal injury and scarring prevented.
Surgical Repair of Trichiasis and Entropion:
The World Health Organization (WHO) recommends a simplified grading system for trachoma.[14] This is summarized below:
The overall prognosis of trachoma is good. Early diagnosis and treatment is the key to minimize irreversible complications and damage to the eye. In recent years, community-based implementation of the SAFE strategy has improved the prognosis for thousands at risk. A study conducted in South Sudan showed significant reductions in the prevalence of active disease as a result of practicing this strategy.[15]
Patient education should be centered around the avoidance of overcrowding and poor hygiene. Hand-eye contact should be kept to a bare minimum. Frequently scratching the eyes should be avoided. Practicing good hygiene, particularly regularly washing hands, should be encouraged. Infected people should immediately be quarantined from the rest of the members of the family and also friends and associates. Once the diagnosis has been made, a proper understanding of the disease nature, its means of spread, and the preventive measures should be given to the patient. Patients should also be warned regarding the possible complications owing to non-compliance to treatment or treatment failure.
Trachoma is a very common infection that is often first seen by the primary care provider or the emergency department provider. These clinicians should always consult with the ophthalmologist before starting any treatment. The disease needs to be dealt with in time to avoid morbidity. Coordination among healthcare professionals is vital for better patient outcomes. Ophthalmologists, opticians, dermatologists, nurses, and pharmacists all need to work in coherence to tackle the disease and all the possible complications. Even after treatment, the patient should be closely followed until the symptoms have subsided, and the visual acuity is normal. Surgeons also need to be involved since surgical interventions may be required to avoid complications. Interprofessional communication is the key to manage the problem at its core appropriately.
An interprofessional team approach is necessary. The clinicians will decide the course of treatment and prescribe appropriate therapy. Nursing can assist in patient education about the disease, as well as assess therapeutic effectiveness and patient compliance. Pharmacists should verify dosing and perform medication reconciliation to ensure the absence of drug-drug interactions. Any concerns form nursing or pharmacy should be reported to the treating clinicians promptly. Trachoma management will be optimized by this type of interprofessional, collaborative approach, leading to better patient outcomes.
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