**15. Corneal diseases in children**

The cornea is the anterior transparent, avascular anatomical structure of the human eye. It constitutes 2/3 of the total refractive capacity. There are many congenital and acquired corneal diseases, which may lead to blindness if left untreated. Corneal dystrophies, congenital anomalies, corneal ectasias, metabolic keratopathies and infectious diseases are the main corneal diseases that may be diagnosed in a child. Most of the corneal pathologies disturb the transparency of the organ and should be referred to an ophthalmologist immediately. Microcornea, megalocornea, anophthalmos and microphthalmos are rare congenital anomalies that affect cornea. Microphthalmos is defined as the developmental arrest of all ocular structures, while anophthalmos is the complete failure of the eye development.

Corneal involvement (corneal edema, infiltrations or erosions) may be seen in cystinosis, mucopolysaccharidoses, Wilson disease, Fabry disease and tyrosinaemia type 2. The treatment of the systemic disease is the mainstay treatment of these metabolic keratopathies.

Corneal dystrophies and corneal ectasias are frequently diagnosed during puberty or later. They are structural diseases of the cornea and mostly genetically determined, but the clinical picture rarely occurs in childhood. Keratoconus is the most common corneal ectasia of the human eye. It is typically diagnosed during puberty with unilateral impairment of vision. Corneal thinning and irregular astigmatism are the main features of the keratoconus. Hard contact lenses and corneal transplantation are treatment options based on the severity of the disease (Ciralsky & Colby, 2007).

#### **15.1 Keratitis**

18 Complementary Pediatrics

ceftriaxone and topical penicillin as well. Infection with herpes is rarer but requires prompt therapy with acyclovir. Chemical cases are caused by silver nitrate and occur within 24 hours life. Tetracyclin, erythromyicin ointments or povidone-ioidine drops can be used for

Conjunctivitis in children is one of the most common reasons to visit a pediatrician. Majority of these infections are self-limited and does not require therapy. This section covers a variety of infectious conjunctival diseases that might be confronted in routine pediatrics practice.

Red eye is one of the most important ophthalmological emergencies. There are several causes such as conjunctivitis, keratitis, uveitis etc. Fortunately, majority of the red eye occurs due to conjunctivitis. The underlying etiology is almost always bacterial in children. However, it can be viral or allergic. During examination there are some key points that will

Symptoms: Allergic cases will always have prominent itching. Bacterial cases will always

Presence and nature of discharge: Bacterial infections will have a purulent, yellow-green discharge. Viral cases will have a serous or mucoid discharge. Allergic cases will have

Laterality: Bacterial cases can be either unilateral or bilateral. Viral and allergic conjunctivitis

Cul-de-sac: Always pull the lower eyelid away from the globe to examine the cul-de-sac. Bacterial conjunctivitis will have tarsal papillae. Viral and allergic conjunctivitis will have

Systemic associations: Viral conjunctivitis might be associated with upper respiratory infections. Allergic conjunctivitis might be seen with upper respiratory allergic symptoms. First-line therapy for bacterial conjunctivitis is topical flouroquinolone. In many cases polysporin, erythromycin or trimethoprim/sulfa is effective. Viral conjunctivitis is self-

The cornea is the anterior transparent, avascular anatomical structure of the human eye. It constitutes 2/3 of the total refractive capacity. There are many congenital and acquired corneal diseases, which may lead to blindness if left untreated. Corneal dystrophies, congenital anomalies, corneal ectasias, metabolic keratopathies and infectious diseases are the main corneal diseases that may be diagnosed in a child. Most of the corneal pathologies disturb the transparency of the organ and should be referred to an ophthalmologist immediately. Microcornea, megalocornea, anophthalmos and microphthalmos are rare congenital anomalies that affect cornea. Microphthalmos is defined as the developmental arrest of all ocular structures, while anophthalmos is the complete failure of the eye

limited. For allergic cases topical antihistaminic drops are effective.

prophylaxis.

have discharge.

tarsal follicles.

development.

**14.1.1 Conjunctivitis** 

help to differentiate the etiology:

occur almost always bilateral.

serous discharge with excessive tearing.

**15. Corneal diseases in children** 

Staphylococcus aeurus, staphylococcus epidermidis, and streptococcus pneumonia are the most common organisms that cause infectious keratitis. Bacterial keratitis usually occurs in patients with damaged corneal epithelial integrity. However, Neisseria gonorrhoeae, Corynebacterium diphteriae, Listeria and Haemophilus species may lead to keratitis in the presence of intact epithelium. Bacterial keratitis is characterized by oval shaped corneal infiltrations surrounded by corneal edema, conjunctival hyperemia (injection), ocular pain and photophobia.

Fig. 7. Gonococcal keratoconjunctivitis

Pseudomonas aeruginosa keratitis tend be very severe and typically produces stromal necrosis with a shaggy surface and adherent mucopurulent exudates. It is an infection usually seen in contact lens users with a damaged corneal epithelial surface. The infection may progress rapidly ending with corneal perforation. In the management of keratitis, ampiric broad-spectrum therapy is recommended until the offending microorganism is identified in the culture. If the type of bacteria is identified from the stained diagnostic smear, then appropriate single drug therapy may be considered.

Herpes simplex virus (HSV) infection is more commonly acquired in adolescence than in childhood. It can be transmitted to neonates as they pass through the birth canal of a mother with genital infection that can lead to serious systemic disorders in the newborns. Primary ocular HSV infection is a form of HSV infection that typically manifests in children aged between 6 months and 5 years. It causes unilateral blepharoconjunctivitis that has signs such

Pediatric Ophthalmology / Eye and Disorders 21

Shigella and Yersinia) dysentery. Corneal diseases usually respond to topical corticosteroids

The uvea is a pigmented structure that primarily lies between the retina and the sclera and constitutes the vascular portion of the eye. It comprises the iris, ciliary body and choroid. Uveitis, by strict definition implies an inflammation of the uveal tract. Uveitis is named according to the anatomical location of inflammation in the uvea. Anterior uveitis may be subdivided into: Iritis and iridocyclitis. Iritis is primarily the inflammation of the iris tissue. On the other hand, iridocyclitis involves both the iris and the pars plicata of the ciliary body. Intermediate uveitis is defined as inflammation predominantly involving the pars plana, the peripheral retina and the vitreous. Posterior uveitis involves the fundus posterior to the vitreous base. Panuveitis implies involvement of the entire uveal tract without a

Pediatric uveitis may be categorized into 4 types of uveitis based on the anatomical location of the inflammatory process. These are anterior (non-granulomatous and granulomatous), intermediate and posterior uveitis. Etiologic factors associated with these uvetis in children

Anterior non-granulomatous uveitis: Idiopathic, HLA-B27 associated, juvenile rheumatoid arthritis (JRA), ankylosing spondylitis, Reiter's disease, psoriasis, inflammatory bowel disease, nephritis, systemic lupus erythematosus, Herpes Simplex virus (HSV), Lyme

Anterior granulomatous uveitis: Sarcoidosis, inflammatory bowel disease, syphilis, Herpes simplex virus, tuberculosis, Behcet's disease, multiple sclerosis, fungal disease, Whipple's

Posterior Uveitis: Toxocariasis, Toxoplasmosis, Leukemia, Tuberculosis, Intraocular Foreign Body, Vogt-Koyanagi Harada Syndrome (VKH), Cytomegalovirus, HSV/VZV, inflammatory bowel disease, syphilis, Behcet's disease, systemic lupus erythematosus, Kawasaki's disease,

Anterior uveitis is the most common form of uveitis. Features are typically with sudden onset of unilateral pain, photophobia and redness, which may be associated with lacrimation. Occasionally patients may notice mild ocular discomfort a few days before the acute attack when clinical signs are absent. Visual acuity is usually good. The presence of vitreal cells in an active vitritis are the main signs of pars planitis. Posterior uveitis encompasses retinitis, choroiditis and retinal vasculitis. Some lesions may originate primarily in the retina or choroid but often there is involvement of both (Sauberan, 2010).

Special investigations such as skin tests, serology and radiology are indicated in posterior

Treatment of the majority of uveitis involves predominantly the use of anti-inflammatory and immunosuppressive agents. Antibiotic therapy for infectious diseases may be

Intermediate uveitis: JRA, Pars Planitis, Multiple Sclerosis, Lyme disease, Sarcoidosis.

sarcoidosis, polyarteritis nodosa, Wegener's granulomatosis (Kanski, 2011).

uveitis, granulomatous inflammation, recurrent uveitis and bilateral uveitis.

(Kanski, 2011).

are as follows.

disease, leprosy.

disease, leukemia, drug-induced.

**16. Pediatric uveitis** 

predominant site of inflammation (Kanski, 2011).

as cutaneous or eyelid marginal vesicles, or ulcers on the bulbar conjunctiva that can be rarely accompanied by dendritic epithelial keratitis. Primary ocular HSV infection is a self limited disease that usually resolves spontaneously. Oral antiviral therapy can speed up the resolution.

Dendritic ulcers, stromal necrotizing keratitis and disciform keratitis are forms of recurrent ocular infection of HSV. These may also occur in this age group. Topical and oral antiviral therapy can be used in the management of recurrent HSV keratitis.

Adenoviruses are the most common viral pathogens that may cause viral keratitis in a child. Pharyngoconjunctival fever (PCF) and epidemic keratoconjunctivitis (EPC) are 2 different clinical pictures that are caused by different serotypes of adenoviruses. PCF is caused by types 3, 4 and 7, while EPC is caused by types 8, 19 and 37. Corneal involvement is much more common and severe in EPC. Keratitis may persist for years in some cases. PCF is the less severe form of the disease. Keratitis is usually mild and self limiting. Mild to moderate fever may accompany PCF. The management of adenoviral keratitis is usually conservative. Topical steroids and cyclosporine may be tried to reduce inflammation. Reduction of transmission risk by avoiding contact with infected patients during the initial 7-10 days of the active disease and by good hygiene is much more important than its management. Ophthalmologists are well experienced about EKC, because unfortunately the eye clinics are usually the most common places to come in contact with the adenovirus and many ophthalmologists are infected once or more with adenoviruses. Many outbreaks occur due to improperly disinfected diagnostic instruments (Kanski, 2011).

#### **15.2 Allergic diseases affecting the cornea**

Vernal keratoconjunctivitis is an allergic eye disease that is mainly seen in male children. Symptoms include itching, photophobia, and mucoid discharge. Corneal findings consist of Horner-Trantas dots (degenerated eosinophils and epithelial cells) in the limbal area, punctate epithelial erosions and shield ulcer (an oval noninfectious epithelial ulcer). Corneal findings are generally accompanied by conjunctival ones which are hyperemia, conjunctival edema (chemosis) and papillary hypertrophy. Topical antihistamines and mast-cell stabilizers can be used in the management of vernal conjunctivitis. Severe cases may require topical corticosteroid or topical immune-modulating agents such as cyclosporine.

Atopic keratoconjunctivitis is a rare bilateral allergic eye disease that is most commonly diagnosed in young men, but also in children. Clinical picture is similar to vernal keratoconjunctivitis, but more severe. The papillary hypertrophy are less developed compared to vernal keratoconjunctivitis. The history of allergy such as allergic asthma or atopic dermatitis is commonly associated. Keratopathy leading to total corneal neovascularization may occur. Management is similar to vernalis keratoconjunctivitis, but the disease is less responsive.

#### **15.3 Reiter syndrome**

It is characterized by the ocular triad (conjunctivitis/ episcleritis, iridocyclitis, or keratitis), urethritis and arthritis. It is usually associated with gram-negative bacterial ( Salmonella, Shigella and Yersinia) dysentery. Corneal diseases usually respond to topical corticosteroids (Kanski, 2011).
