Chapter 6 Neonatal Conjunctivitis (Ophthalmia Neonatorum) JONATHAN C. SONG Table Of Contents |
LABORATORY TESTS MEDICAL MANAGEMENT REFERENCES |
Neonatal conjunctivitis is defined as conjunctivitis presenting before 1 month
of age (Fig. 1).1 Generally it can be divided into noninfectious and infectious categories. The
most common noninfectious cause is a chemical conjunctivitis induced
by silver nitrate solution used for prophylaxis against infectious
conjunctivitis. Bacterial, chlamydial, and viral infections are major
causes of infectious neonatal conjunctivitis; chlamydia is the most
common.2,3 Other infectious agents that the infant may acquire as it passes through
the birth canal during include, Streptococcus spp., Staphylococcus spp., Escherichia coli, Haemophilus spp., Neisseria gonorrhea, and herpes simplex.2 The time of onset of the conjunctivitis as well conjunctival scraping
can aid in the diagnosis of the specific etiology of the neonatal conjunctivitis Table 1.
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LABORATORY TESTS |
Laboratory studies for neonatal conjunctivitis are essential for proper management and diagnosis. Initial culture on chocolate agar or a Thayer-Martin test for N. gonorrhoeae should be obtained as well as blood agar for other bacteria. Chlamydial infection can be ruled out with a conjunctival scraping Giemsa stain for intracytoplasmic inclusion bodies or direct immunofluorescent antibody assay. In herpetic conjunctivitis, gram stain may reveal multinucleate giant cells or Papanicolaou smear may show eosinophilic intranuclear inclusions in epithelial cells. Culture for herpes simplex virus also can be indicated if a corneal epithelial defect is present or the diagnosis cannot be made on ocular examination alone with presence of vesicular lesions.4 |
MEDICAL MANAGEMENT | |
Topical 1% silver nitrate, 0.5% erythromycin, and 1% tetracycline
are considered equally effective for prophylaxis of ocular
gonorrhea and chlamydial ophthalmia in newborn infants.5–6 Recent studies indicate that 2.5% povidone-iodine solution also
may be effective in preventing neonatal ophthalmia and appears to cause
less chemical conjunctivitis as compared with either silver nitrate
or erythromycin.7 Specific treatment for chemical conjunctivitis is not necessary, with
spontaneous resolution in 2 to 3 days. Specific treatment for infectious neonatal conjunctivitis is based on the clinical picture and the findings on Gram, Giemsa, and Papanicolaou stains. Most bacterial conjunctivitis respond quickly to topical antibiotic treatment; erythromycin, or bacitracin ointment for gram-positive organisms; gentamicin or tobramycin drops for gram-negative organisms; and fortified topical antibiotics for Pseudomonas.8 Gonococcal conjunctivitis can progress rapidly. It presents with severe purulent conjunctivitis with lid edema and chemosis (Fig. 2). This organism can penetrate intact corneal epithelium and cause rapid ulceration and perforation. Acute neonatal conjunctivitis should be treated as gonococcal conjunctivitis until culture results become available, after which the treatment can be altered based on laboratory results. Treatment before laboratory results should include topical erythromycin ointment and penicillin G intravenous (IV) or intramuscular (IM) third-generation cephalosporin. Because of the prevalence of penicillin-resistant N. gonorrhoeae, the treatment of choice for this organism is a systemic, third-generation cephalosporin such as ceftriaxone 30 to 50 mg/kg per day in divided doses IV or IM, not to exceed 125 mg.9,10 Irrigation of the affected eyes with saline until discharge is eliminated may be useful. In addition, a single dose of cefotaxime 100 mg/kg IM is an alternative treatment.11 The mother and her sexual contacts also should be treated. A pediatrician should be consulted for possible extraocular involvement.12 Chlamydial conjunctivitis has a later onset than gonococcal conjunctivitis typically from 3 to 10 days after birth. It is much more indolent and less severe. Diagnosis is made by observing intracytoplasmic inclusion bodies by Giemsa stain or direct immunofluorescent assay, which has high sensitivity and specificity.13,14Treatment includes both topical erythromycin ointment and oral erythromycin 30 to 50 mg/kg per day divided in four doses. Typical treatment lasts for 2 weeks to prevent recurrence and secondary pneumonitis.15 Both parents also should be treated for chlamydia even if they are asymptomatic.16 Herpetic conjunctivitis can be the sole manifestation of a neonate infected with herpes simplex. Most cases of herpetic conjunctivitis are type II; however, up to 30% can be type I.17,18 Most present with later onset conjunctivitis with corneal keratitis usually presenting as microdendrites or small geographic ulcers. Treatment consists of topical trifluorothymidine 1% drops every 2 hour or 3% vidarabine ointment.19 In cases with systemic involvement (e.g., pneumonitis, septicemia, or meningitis), systemic acyclovir should be used. |