Abstract
Abstract: :
Purpose: Parvovirus B19 causes erythema infectiosum (fifth disease) in children. The virus has been associated with several autoimmune diseases and was found in synovium or serum from patients with long–standing arthritis or other rheumatic diseases. We investigated serum– and aqueous fluid samples of patients with endogenous uveitis. Methods: Sera of 70 consecutive uveitis patients were investigated for IgG against structural proteins VP1 and VP2 and non–structural protein NS1 by western blot–technique. Viral DNA in serum was assessed by quantitative PCR. Simultaneous DNA analysis was also done from aqueous fluid samples of 11 uveitis patients and of 10 patients without uveitis during routine cataract extraction. Results: In 15 (21.4 %, healthy population: 16 of 100000) of the 70 serum samples (mean age 46.9 years, range 9–82 years, 48 women, 22 men) viral DNA was detected. IgG directed against structural protein VP1 or VP2 was found in 60 patients (85.7 %, healthy population 80 %) and IgG against non–structural protein NS1 in 33 patients (47.1 %, healthy population: 22 %). In none of the patients, IgM antibody as a serological marker for acute parvovirus infection was found. Patients with posterior uveitis (n = 11) had detectable serum DNA in 54.5 % (p=0.021). In this group, deterioration of visual acuity (> 2 Snellen lines) showed the highest number with 72.7% (all patients: 58.6 %; p=0.219). In 2 of the 11 aqueous fluid – samples, viral DNA was detected. Antibodies against parvovirus B19 were found in both samples, whereas viral DNA was absent in the serum. In the control group of 10 healthy cataract patients, 3 had detectable DNA in the aqueous humor, one of these 3 had also detectable levels of viral DNA in serum. Conclusions: Prevalence of IgG antibodies against NS1 protein in serum samples and DNA in serum and aqueous fluid samples is increased in uveitis patients compared to normal population, suggesting a persistent infection. DNA in aqueous humor samples show for the first time persistence of parvovirus B19 in the eye in uveitis and in healthy patients. The role of parvovirus DNA in the aqueous fluid and of IgG antibodies against NS1 in the pathogenesis of uveitis can not be defined at present.
Keywords: uveitis-clinical/animal model • clinical (human) or epidemiologic studies: prevalence/incidence • aqueous