Uveitis in children is a common name for inflammatory diseases of the vascular membrane of the eye. The main causes are systemic autoimmune diseases, infections (viral, bacterial, fungal), allergic and toxic effects on the choroid. Anterior uveitis is manifested by corneal syndrome and pain in the eye, posterior — by a sharp deterioration in vision in the absence of pain syndrome. Biomicroscopy, coherent optical tomography, visometry, and other instrumental studies are prescribed for diagnosis. Treatment is carried out with anti-inflammatory, desensitizing, etiotropic antibacterial and antiviral agents. According to the indications, surgical correction is performed.
The prevalence of the disease in pediatric ophthalmology ranges from 15-38 cases per 100 thousand population, and its specific weight among all eye diseases is 10-15%. The peak of diagnosis of uveitis in pediatric practice falls on adolescence, boys and girls get sick equally often. Polyetiology, diversity and nonspecific symptoms put uveitis among the most dangerous eye diseases and require the doctor to use different diagnostic methods in order to identify the pathology in a timely manner and begin treatment.
The etiological factors of uveitis in children are diverse, but they cannot always be detected even by modern diagnostic methods, so in 28% of cases the process is idiopathic in nature. The remaining causes of choroid inflammation are divided into several groups:
- Infectious factors. The main pathogens are herpesviruses: herpes simplex virus, chickenpox virus, cytomegalovirus. Posterior and middle uveitis occur as a complication of tuberculosis and syphilis, and in endemic regions they can be triggered by Lyme disease. Occasionally, uveitis is caused by a candida infection.
- Systemic autoimmune processes. Juvenile idiopathic arthritis (JIA), which is 20-30% complicated by eye damage, is the main non-infectious factor of uveitis in children. Less often, the pathology is associated with spondyloarthropathies, dermatomyositis, lupus erythematosus. Cases of damage to the choroid in Behcet’s disease are described.
- Regional inflammatory processes. A high risk of developing the disease in children is observed with untreated sinusitis, otitis media, pulpitis. In this case, pathogens penetrate through the common blood flow pathways into the eyeball, provoking infectious and allergic lesions of the vascular membrane.
- Exposure to toxins. Occasionally, the disease occurs with prolonged use of potent drugs: sulfonamides, biphosphonates, anti-tuberculosis antibiotics. The causes of uveitis also include exogenous toxic effects, the use of medications that alter the functioning of the immune system (checkpoint inhibitors).
The vascular membrane is a dense network of capillaries with slow blood flow, which predisposes the settling of infectious pathogens, toxins and immune complexes in it. Another important factor of pathogenesis is the proximity of the orbital artery feeding the choroid to the vascular basin of other parts of the face, which increases the risk of local spread of the inflammatory process from the maxillofacial zone.
Infectious uveitis proceeds according to the general rules of inflammation. Cellular and humoral mechanisms are influenced by specific causes of the disease (bacterial, viral or fungal agents). In the pathogenesis of non-infectious inflammation of the choroid in children, immune reactions that arise under the influence of genetic predisposition, molecular mimicry and increased production of pro-inflammatory cytokines come to the fore.
Pathomorphologically, the disease is characterized by diffuse or focal infiltration of the vascular membrane by activated immune cells, among which macrophages, plasma cells and T-lymphocytes predominate. The variety of clinical forms is due to the activation of different subclasses of T-helper and regulatory molecules, which the doctor takes into account when choosing treatment. The natural outcome of uveitis is fibrosis, neoangiogenesis and atrophic processes.
According to the clinical course, the pathology has acute (up to 3 months), chronic (exacerbations with less than 3 months interval) and recurrent forms. Taking into account the cause, the disease is divided into endogenous, caused by internal factors, and exogenous, provoked by infections or allergic triggers. In practical ophthalmology, systematization by localization of the process is widely used, according to which 4 types of uveitis are distinguished:
- Anterior (37-62%). Inflammation develops in the iris (iritis) or the iris and the ciliary body (iridocyclitis) are simultaneously affected.
- Median (up to 4%). The pathological process involves the posterior parts of the ciliary body (posterior cyclitis), the periphery of the retina, the underlying areas of the vascular membrane (parsplanitis).
- Rear (9-38%). There is a lesion of the vascular membrane itself (chorioiditis) and the retina (chorioretinitis), less often the optic nerve disc (neuroretinitis) is involved in the process.
- Generalized (7-38%). Total involvement of the entire vascular membrane of the eyeball (panuveitis) with the spread to other anatomical structures.
According to the intensity of inflammation, active forms are distinguished, for which a typical cellular reaction is + 0.5 or more, and pathology in remission. Anterior uveitis by the nature of inflammatory changes are classified into serous, fibrinous, purulent and hemorrhagic. Depending on the localization of the pathological focus, choroiditis can be central, paracentral, equatorial and peripheral.
Childhood uveitis is characterized by a low-symptomatic gradual onset, which makes it difficult to diagnose them early. Clinical signs are determined by the localization of the lesion. With iritis and iridocyclitis, the symptoms are similar to keratitis: the patient complains of lacrimation, photophobia, involuntary closing of the eyelids. The diseased eye turns red, when touching it through the skin of the upper eyelid, the child feels severe pain.
With middle and posterior uveitis, the main complaint of the child is a decrease in vision of varying degrees. Central chorioiditis is manifested by a significant deterioration in the function of vision, distortion of visible images and the presence of flashes of light in front of the eyes (photopsias). For paracentral forms, transient blurred vision and the appearance of floating dots are typical, the peripheral variant is mostly asymptomatic.
In 25-30% of cases, uveitis is combined with lesions of other internal organs, so complaints are diverse and depend on the underlying cause. In rheumatic pathologies, joint pain and stiffness of movements are bothered, redness and swelling of the skin are noticeable over the affected joint. Uveitis of an allergic nature is supplemented by signs of pollinosis, allergobronchitis, bronchial asthma.
In children, uveitis often has a severe recurrent course, despite complex treatment, so they have complications faster. When the anterior parts of the vascular membrane are affected, anterior synechiae are formed — the fusion of the iris with the endothelium of the cornea and posterior synechiae — fibrous cords between the iris and the lens. In severe cases, complete overgrowth of the pupil occurs.
A dangerous consequence of uveitis is ophthalmohypertension or secondary glaucoma, which occurs when there is a violation of the outflow of intraocular fluid. The most common complications of choroiditis and chorioretinitis include dystrophy and retinal detachment, optic neuritis, vitreous hemorrhage. The great medical and socio-economic significance of uveitis lies in the risk of irreversible deterioration of vision up to blindness.
During an objective examination of a patient with iridocyclitis, a pediatric ophthalmologist pays attention to the pericorneal injection of blood vessels, the blurring of the iris pattern, the appearance of precipitates on the cornea. Posterior uveitis does not have typical external manifestations. To identify an inflammatory lesion and establish its possible cause, the child is assigned a full range of laboratory and instrumental methods, which include:
- Biomicroscopy of the eye. The diagnosis of anterior uveitis is made in the presence of a cellular suspension in the anterior chamber of more than + 0.5 (which corresponds to 1-5 cells in a field of 1 mm2). With chorioretinitis, exudate in the vitreous body, grayish-yellow retinal infiltrates, macular edema of the retina, retinovasculitis are present.
- Optical coherence tomography. Optical examination of the retina is indicated in choroiditis and chorioretinitis to assess macular edema, detailed visualization of structural changes in the posterior parts of the eyeball. To clarify the zones of ischemia and neovascularization, OCT in children is supplemented by fluorescent angiography (FAG).
- Additional instrumental methods. Visual acuity is assessed using classical visometry, and the functions of the retina and pathways are assessed by perimetry or electrophysiological examination. Rheoophthalmography and angiography of retinal vessels are informative for detecting foci of chorioretinitis.
- Blood tests. When assessing biochemical parameters, the level of acute-phase proteins, proteinogram data and markers of nitrogen metabolism are taken into account. If rheumatic causes of ocular pathology are suspected, the HLA-B27 antigen, antistreptolysin-O, and rheumatoid factor are determined. In case of possible syphilis, ELISA is performed on Treponema pallidum.
Treatment of uveitis in children
Drug therapy of the disease pursues several goals: the relief of the active inflammatory process, the prevention of synechiae, other fibrous complications, and, if possible, the elimination of the etiological factor. Treatment is prescribed by an ophthalmologist in close cooperation with doctors of other specialties — a pediatric rheumatologist, an infectious disease specialist, an allergist immunologist. The following groups of drugs are used in the complex therapy of uveitis in children:
- Mydriatics. Eye drops with M-holinoblockers cause persistent pupil dilation and prevent the development of fibrous changes. They are effective in the acute period of the disease.
- Anti-inflammatory drugs. Relief of inflammation is carried out with the help of systemic nonsteroidal anti-inflammatory drugs and local glucocorticoids (GC). To increase the effectiveness of therapy, GC are administered subconjunctively or parabulbar.
- Immunosuppressors. If hormonal treatment is ineffective, it is enhanced with systemic cytostatics. Such therapy is mainly used for uveitis against the background of connective tissue diseases.
- Fibrinolytics. To prevent fibrinous plastic processes and other complications of uveitis, enzyme solutions (lidase, wobenzyme, collazine) in the form of subconjunctival injections are recommended.
- Detoxification agents. For desensitization of the body, infusions of saline and glucose solutions are used, with pronounced allergic processes, antihistamines are prescribed.
- Antibiotics. Etiotropic agents are used for posterior uveitis after confirmation of the sensitivity of the pathogen. When infected with protozoa (toxoplasma), specific antiprotozoal drugs are indicated.
The help of ophthalmic surgeons is necessary for the complicated course of the disease. With neovascularization and peripheral retinal detachment, laser coagulation is effective, and circular synechiae are removed by laser synechiotomy and iridotomy. With a widespread fibrotic lesion of the vitreous body, vitrectomy is indicated. With panuveitis accompanied by total involvement of the eye, sometimes it is necessary to perform evisceration of the eyeball.
Prognosis and prevention
Early detection and treatment of the disease increases the chances of a full recovery. The prognosis is favorable in children with a mild course of uveitis, the absence of systemic pathologies, and a good response to therapy. A less optimistic prognosis is for patients with initially low visual acuity, the development of complications, a long course of the disease with frequent relapses.
Preventive measures for uveitis have not been developed. Children with rheumatic diseases and other risk factors need regular professional examinations by an ophthalmologist to monitor visual function. To prevent infectious forms, it is necessary to observe general anti-epidemic measures. After the transferred inflammation of the choroid, a dispensary observation is prescribed every 3-6 months for the timely detection and treatment of exacerbations.