Diagnostic methods for Chlamydia trachomatis disease in neonates.

Chlamydia trachomatis is an obligate intracellular parasite responsible for many clinical syndromes, including neonatal conjunctivitis and pneumonia. The gold standard of diagnosis has been isolation in cell culture. However, this requires days of processing. Several rapid diagnostic tests are available. Giemsa staining of conjunctival smears, enzyme immunoassay, and the fluorescein-conjugated monoclonal antibody test. Both the EIA and the FA tests show promise as ideal rapid diagnostic tests. Treatment of chlamydial conjunctivitis must focus upon the eradication of nasopharyngeal carriage as well as cure of ophthalmic symptoms. The need for nasopharyngeal eradication is underscored by the fact that it is the source for chlamydial pneumonia as well as for conjunctival re-infection. Clinical studies have shown that oral erythromycin estolate or ethylsuccinate suspension 50 mg/kg/day twice-daily or four times a day for 14 to 21 days are the therapeutic regimens of choice. Neonatal ocular prophylaxis is currently under study. One per cent silver nitrate does not prevent chlamydial conjunctivitis but preliminary studies do show favorable results with topical erythromycin. Nevertheless, neither 1 per cent silver nitrate nor topical erythromycin eradicate nasopharyngeal carriage, elimination of which is necessary for the prevention of neonatal chlamydial pneumonia.