Detection of herpesvirus DNA by the polymerase chain reaction (PCR) in vitreous samples from patients with necrotising retinitis

Aims-Viral uveitis and retinitis, usually caused by herpesviruses, are comm on in immunosuppressed patients. The diagnosis of viral anterior uveitis an d retinitis is usually clinical. The polymerase chain reaction (PCR) has be en used for the diagnosis of some viral infections, especially those caused by herpesviruses. This paper reports the use of PCR in the diagnosis of vi ral retinitis in vitreous samples from Brazilian patients. Methods-PCR was used for the diagnosis of necrotising retinitis in vitreous samples from patients from the Hospital Sao Geraldo, Universidade Federal de Minas Gerais, Brazil. The vitreous samples were collected by paracentesi s and stored until analysis. Samples were analysed by PCR using specific pr imers designed to amplify herpes simplex virus 1 (HSV-1), varicella tester virus (VZV), or human cytomegalovirus (HCMV). In a case of anterior uveitis , PCR was performed with a sample from the anterior chamber. Results-Herpesvirus DNA was amplified in 11 of 17 samples. HCVM DNA was det ected in nine samples but DNA from HSV-1 and VZV were detected only once ea ch. Conclusion-These results strongly suggest that PCR could be used for a rapi d complementary diagnosis of viral uveitis and retinitis. A prospective stu dy to evaluate the PCR results, clinical evolution, and treatment is impera tive to corroborate the real value of FCR in diagnosis and how it could hel p the clinicians' approach.