Chorioretinitis Clinical Presentation

• In most individuals with chorioretinitis (CR), the history may or may not aid in establishing causal agents. For example, in patients with chorioretinitis associated with congenital infections, eliciting the maternal history of primary viral or flulike illnesses during pregnancy is usually not easy. Dietary habits (preference of raw meat) and pet care (cleaning cat litter box) may imply toxoplasmosis or contact with kittens (catscratch disease). Lack of immunizations in a pregnant woman may also provide some clues to the diagnosis (eg, rubella). On the other hand, a pregnant woman with symptomatic West Nile viral meningoencephalitis may be readily diagnosed using historical, epidemiologic, and laboratory data.
• Many maternal primary infections due to cytomegalovirus (CMV), rubella, herpes simplex virus (HSV), and syphilis occur insidiously and may not be clinically apparent.
• A recent history that includes strabismus, vision loss, and CNS involvement in a toddler exposed to raccoon waste or who has a newly acquired puppy suggests zoonotic roundworm larval infestation (Baylisascaris or Toxocara). These children have an increased risk of developing visceral larva migrans and ocular larva migrans.
• Parinaud oculoglandular syndrome (fever, follicular conjunctivitis, ipsilateral preauricular lymphadenitis), neuroretinitis, and focal retinochoroiditis in children or young adults exposed to kittens may suggest infection due to Bartonella henselae (catscratch disease), especially if they were scratched.

If the inflammation is unilateral, the child may squint, favor the "good eye," or report blurred vision or an inability to see objects. Older children with chorioretinitis may present with photophobia and clumsiness with poor walking balance. The "red eye" phenomenon in snapshots of a child with chorioretinitis may reveal incongruency.

• Include an ophthalmologic examination as part of a detailed physical examination.
• A pediatric ophthalmologist should perform a thorough examination of all visible components of the eye in an infant in whom any congenital infection is suspected.

  • This examination is electively performed and is documented with photographs of the abnormalities in the lens, uvea, and retina and an age-appropriate assessment of vision, visual acuity, and fields.
  • Ophthalmologic examination is also an integral part of monitoring treatment efficacy and disease progress.
  • Ophthalmologic examination can reveal exudative "cotton balls" (ie, focal atrophic and pigmented scars of the retina). Vitreous inflammations can manifest as transient floating opacities. However, these findings are common in all patients with chorioretinitis regardless of the etiology.
• Other abnormal physical findings should be documented; these include intrauterine growth retardation, microcephaly, microphthalmia, cataract, uveitis, hearing defect, osteomyelitis, hepatosplenomegaly, lymphadenopathy, dermal erythropoiesis, carditis, and congenital heart disease.
• CNS involvement may include abnormal muscle tone, changes in reflexes, or both. A complete neurological examination is warranted.
• If amnionitis is suspected at delivery, thorough examination and culture of amniotic fluid and placenta may elicit the pathogen.

• Congenital infection

  • In immunocompetent children, chorioretinitis is usually associated with congenital infection; acquired infection is a less likely cause.
  • T gondii and CMV are the leading causes of congenital infections associated with chorioretinitis.
  • Viral etiologies include vertical or perinatal infections, including HSV, rubella, varicella, Epstein-Barr virus (EBV), lymphocytic choriomeningitis virus (LCMV), and, possibly flavivirus. With the recent increase in the incidence of congenital infection after being at a nadir since 1991, syphilis should be considered in an infant born with chorioretinitis whose mother has untreated or inadequately treated syphilis, particularly if she also has human immunodeficiency virus infection (HIV).^{[15, 16]}
  • Distinguishing these infections from perinatal transmission of other viral illnesses, including HSV, hepatitis B, and HIV is important.
  • The risk of intrauterine infection is highest in infants of women with primary infection and is much less with recurrent infections.
• Acquired chorioretinitis in immunocompetent children: Some children who ingest embryonated T canis or Baylisascaris procyonis eggs may develop visceral larva migrans or ocular larva migrans. Another acquired infection that may lead to chorioretinitis is B henselae.^[17] More than 90% of patients with catscratch disease have a history of recent contact with a cat, often a kitten, and 50-87% of these patients have been scratched.
• Immunocompromised children

  • Chorioretinitis may be associated with systemic infection due to a vast array of pathogens. Any of the infections discussed above may be seen; however, the presentation in an immunocompromised individual may be atypical.
  • Other infections may include congenital or acquired Lyme disease, Yersinia enterocolitica, and Mycobacterium tuberculosis (MTB).^{[18, 19]}
  • Invasive fungal infections may result from Candida,Cryptococcus species, and histoplasmosis.^[20]
  • A species of blackfly (Simulium species) can transmit onchocerciasis (in tropical Africa, Yemen, Saudi Arabia, and parts of Latin America).^[21]
• Noninfectious disease

  • Systemic noninfectious disease, such as sarcoidosis, collagen vascular disease, chronic granulomatous disease (CGD), Behcet disease, and juvenile rheumatoid arthritis may cause chorioretinitis.^[22]
  • Other possible noninfectious processes include chronic infantile, neurological, cutaneous, and articular syndrome (CINCA) syndrome, also known as neonatal onset multisystemic inflammatory disease.^[23]