Neonatal chlamydial infection, which manifests principally as ophthalmia neonatorum (ON) or pneumonia, is a significant cause of neonatal morbidity. Widespread use of silver nitrate drops resulted in a dramatic decline in the incidence of gonococcal ophthalmia but had much less impact on the incidence of neonatal chlamydial infection. Chlamydia trachomatis has become the most common infectious cause of ON in developed countries.A number of prophylactic antibiotic or antiseptic agents have been used to prevent ON. Prophylaxis with 1% silver nitrate ophthalmic drops, 0.5% erythromycin ophthalmic ointment, or 1% tetracycline ointment has comparable efficacy for the prevention of chlamydial ophthalmia but does not offer protection against nasopharyngeal colonization or the development of pneumonia. Erythromycin or tetracycline topically have been used as prophylactic agents because of their allegedly superior activity for the prevention of ON and because they produced less chemical conjunctivitis compared with silver nitrate. However, the relative efficacy of these agents for chlamydial infection and the emergence of beta-lactamase-producing Neisseria gonorrheae has raised questions regarding their effectiveness when applied topically for prophylaxis of ON. Compared with these agents, a 2.5% povidone-iodine ophthalmic solution has been found to have greater efficacy for the prevention of ON generally, and chlamydial ophthalmia specifically. In countries where the incidence of ON is very low, an alternative strategy is to institute prenatal screening and treatment of infected mothers, forgo routine neonatal prophylaxis, and follow-up infants after birth for the possible development of infection. For the treatment of chlamydial ophthalmia or pneumonia, oral erythromycin for 2 weeks is recommended; additional topical therapy is unnecessary. However, in approximately 20-30% of infants, therapy will not eradicate the organism and the infant may require a repeat oral course of antibiotics. The few published studies on the use of the new oral macrolide antibiotics, such as azithromycin, roxithromycin, or clarithromycin for chlamydial infections in neonates suggest that these agents may be effective; however, more data on their tolerability and efficacy in this patient group are warranted.
