Prevalence of parvovirus B19-specific antibodies and of viral DNA in patients with endogenous uveitis.
BACKGROUND
Parvovirus B19 causes erythema infectiosum (fifth disease) in children. The virus has been associated with several autoimmune diseases and has been 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 performed on aqueous fluid samples from 11 uveitis patients and 10 patients without uveitis during routine cataract extraction.


RESULTS
In 15 (21.4%; healthy population: 16 of 10,000) of the 70 serum samples (mean age 42.69 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 was IgM antibody as a serological marker for acute parvovirus infection found. Patients with posterior uveitis (n=11) had detectable serum DNA in 54.5% (p=0.021). This group displayed the highest rate of deterioration of visual acuity (>2 Snellen lines), at 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; 1 of these 3 also had detectable levels of viral DNA in serum.


CONCLUSIONS
Prevalence of IgG antibodies against NS1 protein in serum samples and DNA in serum is increased in uveitis patients compared with the normal population, suggesting a persistent infection. The presence of DNA in aqueous humor samples shows, for the first time, persistence of parvovirus B19 in the eye in uveitis and also in healthy patients. The role of parvovirus DNA in the aqueous fluid and of IgG antibodies against NS1 in the pathogenesis of uveitis cannot be defined at present.
Heinz
Carsten
C
Department of Ophthalmology, St. Franziskus Hospital Muenster, Hohenzollernring 54, 48145, Muenster, Germany. Carsten.Heinz@uveitis-zentrum.de
Plentz
Annelie
A
Bauer
Dirk
D
Heiligenhaus
Arnd
A
Modrow
Susanne
S
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000914:Antibodies, Viral / Q000276:immunology*; D001082:Aqueous Humor / Q000821:virology; D002648:Child; D004279:DNA, Viral / Q000235:genetics*; D004797:Enzyme-Linked Immunosorbent Assay; D015828:Eye Infections, Viral / Q000453:epidemiology / Q000821:virology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010322:Parvoviridae Infections / Q000453:epidemiology / Q000821:virology*; D016732:Parvovirus B19, Human / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification; D012189:Retrospective Studies; D016036:Seroepidemiologic Studies; D014606:Uveitis, Anterior / Q000453:epidemiology / Q000821:virology*; D015866:Uveitis, Posterior / Q000453:epidemiology / Q000821:virology*
D000914:Antibodies, Viral; D004279:DNA, Viral