Transfusion-transmitted virus DNA in serum, tear and aqueous humour of patients undergoing cataract operation

Association Between Torque Teno Virus and Systemic Immunodeficiency in Patients With Uveitis With a Suspected Infectious Etiology

PURPOSE

To determine the correlation between the presence of torque teno virus (TTV) in the aqueous humor of patients with uveitis and clinical information, including immunodeficiency history.

DESIGN

Multicenter, retrospective, cross-sectional study.

METHODS

Fifty-eight patients with uveitis with a suspected infectious etiology and 24 controls with cataract or age-related macular degeneration were included. We used quantitative polymerase chain reaction to test all subjects for TTV and multiplex polymerase chain reaction to test uveitis subjects for common ocular pathogens. When possible, both serum and aqueous humor samples were tested. Ocular TTV positivity was compared with age, sex, and a history of systemic immunodeficiency with logistic analysis.

RESULTS

Ocular TTV positivity was found in 23%, 11%, and 0% of patients with herpetic uveitis, nonherpetic uveitis, and controls, respectively. Among patients with herpes infection, positivity for ocular TTV was found in 43%, 8%, 14%, and 50% of patients with cytomegalovirus retinitis, iridocyclitis, acute retinal necrosis, and Epstein-Barr virus-positive uveitis, respectively. Patients with cytomegalovirus retinitis showed a significantly higher rate of ocular TTV infection than controls (P = .008). Serum analysis revealed TTV positivity in 90% of patients with uveitis and in 100% of controls. Age- and gender-adjusted logistic analysis revealed a correlation between ocular TTV positivity and systemic immunodeficiency (P = .01), but no correlations between ocular TTV and age, gender, or viral pathogenic type.

CONCLUSIONS

These findings suggest that positivity for ocular TTV was correlated with a clinical history of systemic immunodeficiency.

Detection of Torque Teno Virus (TTV) and TTV-Like Minivirus in patients with presumed infectious endophthalmitis in India

Human anelloviruses (Torque Teno Virus (TTV) and TTV Like Mini Virus (TLMV)) are now being reported at a high prevalence across the world, with a controversial disease-inducing potential. The aim of this study was to investigate the role of these anellovirus in vitreous of patients with presumed infectious endophthalmitis. After informed consent, vitreous fluid from patients with endophthalmitis (n = 103) and non-infectious pathologies (n = 102) were analyzed for the presence of TTV and TLMV DNA by qPCR with the limit of quantification defined as 100 copies per reaction. Among the patients clinically diagnosed with endophthalmitis, 29 of the 40 culture proven samples (72.5%) and 42 out of 63 (66.6%) of culture-negative samples were positive for presence of TTV/TLMV. Interestingly, 51 of the 102 (50%) samples in the control group were also positive for TTV/TLMV. Comparing the clinical outcome among patients diagnosed with endophthalmitis, we observed no significant association in the final visual acuity of patients who were positive for presence of TTV/TLMV, however, these patients had significantly higher repeat antibiotic injections (p = 0.03). Further evidence is however needed to correlate TTV / TLMV with a particular pathology or group of pathologies in the eye.

Paucibacterial Microbiome and Resident DNA Virome of the Healthy Conjunctiva

Purpose

To characterize the ocular surface microbiome of healthy volunteers using a combination of microbial culture and high-throughput DNA sequencing techniques.

Methods

Conjunctival swab samples from 107 healthy volunteers were analyzed by bacterial culture, 16S rDNA gene deep sequencing (n = 89), and biome representational in silico karyotyping (BRiSK; n = 80). Swab samples of the facial skin (n = 42), buccal mucosa (n = 50), and environmental controls (n = 27) were processed in parallel. 16S rDNA gene quantitative PCR was used to calculate the bacterial load in each site. Bacteria were characterized by site using principal coordinate analysis of metagenomics data. BRiSK data were analyzed for presence of fungi and viruses.

Results

Corynebacteria, Propionibacteria, and coagulase-negative Staphylococci were the predominant organisms identified by all three techniques. Quantitative 16S PCR demonstrated approximately 0.1 bacterial 16S rDNA/human actin copy on the ocular surface compared with greater than 10 16S rDNA/human actin copy for facial skin or the buccal mucosa. The conjunctival bacterial community structure is distinct compared with the facial skin (R = 0.474, analysis of similarities P = 0.0001), the buccal mucosa (R = 0.893, P = 0.0001), and environmental control samples (R = 0.536, P = 0.0001). 16S metagenomics revealed substantially more bacterial diversity on the ocular surface than other techniques, which appears to be artifactual. BRiSK revealed presence of torque teno virus (TTV) on the healthy ocular surface, which was confirmed by direct PCR to be present in 65% of all conjunctiva samples tested.

Conclusions

Relative to adjacent skin or other mucosa, healthy ocular surface microbiome is paucibacterial. Its flora are distinct from adjacent skin. Torque teno virus is a frequent constituent of the ocular surface microbiome. (ClinicalTrials.gov number, NCT02298881.)

Identification of torque teno virus in culture-negative endophthalmitis by representational deep DNA sequencing

PURPOSE

To test the hypothesis that uncultured organisms may be present in cases of culture-negative endophthalmitis by use of deep DNA sequencing of vitreous biopsies.

DESIGN

Single-center, consecutive, prospective, observational study.

PARTICIPANTS

Aqueous or vitreous biopsies from 21 consecutive patients presenting with presumed infectious endophthalmitis and 7 vitreous samples from patients undergoing surgery for noninfectious retinal disorders.

METHODS

Traditional bacterial and fungal culture, 16S quantitative polymerase chain reaction (qPCR), and a representational deep-sequencing method (biome representational in silico karyotyping [BRiSK]) were applied in parallel to samples to identify DNA sequences corresponding to potential pathogens.

MAIN OUTCOME MEASURES

Presence of potential pathogen DNA in ocular samples.

RESULTS

Zero of 7 control eyes undergoing routine vitreous surgery yielded positive results for bacteria or virus by culture or 16S polymerase chain reaction (PCR). A total of 14 of the 21 samples (66.7%) from eyes harboring suspected infectious endophthalmitis were culture-positive, the most common being Staphylococcal and Streptococcal species. There was good agreement among culture, 16S bacterial PCR, and BRiSK methodologies for culture-positive cases (Fleiss' kappa of 0.621). 16S PCR did not yield a recognizable pathogen sequence in any culture-negative sample, whereas BRiSK suggested the presence of Streptococcus in 1 culture-negative sample. With the use of BRiSK, 57.1% of culture-positive and 100% of culture-negative samples demonstrated the presence of torque teno virus (TTV) sequences, compared with none in the controls (P=0.0005, Fisher exact test). The presence of TTV viral DNA was confirmed in 7 cases by qPCR. No other known viruses or potential pathogens were identified in these samples.

CONCLUSIONS

Culture, 16S qPCR, and BRiSK provide complementary information in presumed infectious endophthalmitis. The majority of culture-negative endophthalmitis samples did not contain significant levels of bacterial DNA. "Culture negativity" does not seem to be due to failure of growth of fastidious bacteria. The small DNA virus TTV was unexpectedly found in all culture-negative samples and some culture-positive samples. This study cannot distinguish whether TTV is a direct intraocular pathogen, an adjuvant for inflammation, a general marker of inflammation, or a commensal virus but provides a testable hypothesis for a pathogenic mechanism in culture-negative endophthalmitis.

Human anelloviruses and the central nervous system

Torque teno virus and related anelloviruses are a recent addition to the list of agents that cause chronic productive infections and high levels of plasma viraemia in humans. Many aspects of the natural history and pathogenesis of these under many respects surprising viruses are still poorly understood. In this review, we briefly outline the general properties of anelloviruses, examine what is currently known about the interactions they establish with the central nervous system (CNS), and discuss the possible pathological consequences.

Prevalence and clinical significance of SEN virus infection in patients with non A-E hepatitis and volunteer blood donors in Shanghai

AIM: To explore the prevalence of SEN virus (SENV) in patients with non A-E hepatitis and volunteer blood donors in Shanghai.

METHODS: According to the published gene sequences, primers from the conserved region were designed. Then, the prevalence of SEN virus in 30 samples from healthy voluntary blood donors and 30 samples from patients with non A-E hepatitis were detected by nested-PCR of SENV-D/H. Some PCR products were cloned and sequenced.

RESULTS: The specificity of genotype-specific PCR was confirmed by sequencing, the SENV DNA was detected in 53.3% of the patients with non A-E hepatitis and 10% of the blood donors. The prevalence of SENV-D/H viremia was significantly higher in patients with non A-E hepatitis than in blood donors (P = 0.0002). SENV-H subtype and SENV-D subtype were found in 2 and 1 samples, respectively from blood donors. SENV-H subtype, SENV D subtype, mixed SENV-D and SENV-H subtype were found in 8, 6 and 2 samples, respectively, from patients with non A-E hepatitis.

CONCLUSION: The gene type of SENV in patients with non A-E hepatitis and blood donors in shanghai is D or H subtype, and transfusion is not the only transmitting form of SENV.