VALIDATION OF A SALIVA-BASED TEST FOR THE MOLECULAR DIAGNOSIS OF SARS-CoV-2 INFECTION

BackgroundSince the beginning of the pandemic, clinicians and researchers have been searching for alternative tests to improve screening and diagnosis of SARS-CoV-2 infection (Y. Yang et al., medRxiv 2020; W. Wang et al., 2020.3786; A Senok et al., Infect Drug Resist 2020). Currently, the gold standard for virus identification is the nasopharyngeal (NP) swab (N. Sethuraman et al., JAMA 2020; A.J. Jamal et al Clinical Infect Disease 2021). Saliva samples, however, offer clear practical and logistical advantages (K.K.W To et al, Clinical Microb and Infect; A.L. Wylle et al. N Engl J Med 2020; N. Matic et al, Eur J Clin 2021) but due to lack of collection, transport, and storage solutions, high-throughput saliva-based laboratory tests are difficult to scale up as a screening or diagnostic tool (D. Esser et al., Biomark Insights 2008; E. Kaufman et al., Crit Rev Oral Biol Med2002). With this study, we aimed to validate an intra-laboratory molecular detection method for SARS-CoV-2 on saliva samples collected in a new storage saline solution, comparing the results to NP swabs to determine the difference in sensitivity between the two tests. MethodsIn this study, 156 patients (cases) and 1005 asymptomatic subjects (controls) were enrolled and tested simultaneously for the detection of the SARS-CoV-2 viral genome by RT-PCR on both NP swab and saliva samples. Saliva samples were collected in a preservative and inhibiting saline solution (Biofarma Srl). Internal method validation was performed to standardize the entire workflow for saliva samples. ResultsThe identification of SARS-CoV-2 conducted on saliva samples showed a clinical sensitivity of 95.1% and specificity of 97.8% compared to NP swabs. The positive predictive value (PPV) was 81% while the negative predictive value (NPV) was 99.5%. Test concordance was 97.6% (Cohens Kappa=0.86; 95% CI 0.81-0.91). The LoD of the test was 5 viral copies for both samples. ConclusionsRT-PCR assays conducted on a stored saliva sample achieved similar performance to those on NP swabs and this may provide a very effective tool for population screening and diagnosis. Collection of saliva in a stabilizing solution makes the test more convenient and widely available; furthermore, the denaturing properties of the solution reduce the infective risks belonging to sample manipulation.

Determinants of ante-partum depression: a multicenter study.

INTRODUCTION: Ante-partum depression (APD) is usually defined as a non-psychotic depressive episode of mild to moderate severity, beginning in or extending into pregnancy. APD has received less attention than postpartum depression. This is a cross-sectional study carried out in the Obstetrics and Gynaecology (OG) departments of four different general hospitals in Italy. METHODS: Women attending consecutively the OG departments for their first ultrasound examination were asked to fill in the Edinburgh Postnatal Depression Scale (EPDS) in its Italian validated version. We used the total scores of the EPDS as a continuous variable for univariate and linear regression analyses; in accordance with the literature, the item analysis of EPDS was carried out by classifying the sample as women with "no depression" (scores 0-9), "possible depression" (scores 10-12), "probable depression" (scores 13+) and "probable APD" (scores 15+). RESULTS: The number of women recruited was 1,608. The EPDS assessment classified 10.9 % of the women as possibly depressed, 8.3 % as probably depressed and 4.7 % probably affected from an APD. EPDS score distribution was associated with nationality (higher scores for foreigners), cohabitation (higher scores for women living with friends or in a community), occupation (higher scores for housewives), past episodes of depression and use of herbal drugs. Non-depressed women had significantly lower values on all ten items as compared with depressed women, however, the pattern of item distribution on the EPDS scale remained similar across depression severity groups. In all four groups item 4 (anxious depression) attained the highest scores, while item 10 (suicidality) attained the lowest scores.

The natural history of occult choroidal neovascularisation associated with age-related macular degeneration. A systematic review

<p><b>INTRODUCTION</b>The purpose of this review is to combine the results of existing literature on the natural history of occult choroidal neovascularisation (CNV) associated with age-related macular degeneration (AMD).</p><p><b>MATERIALS AND METHODS</b>Published reports evaluating eyes with occult CNV in AMD patients were selected for meta-analysis based on a computerised MEDLINE search. Pooled estimates of the proportions of eyes with a vision loss greater than 2 to 3 (moderate vision loss) or 6 lines (severe vision loss) at 1 year and 2 to 3 years, respectively, or developing a classic component on fluorescein angiography at 1 year were measured.</p><p><b>RESULTS</b>There is no significant heterogeneity among published rates of visual loss and development of classic CNV. The overall pooled estimates (95% confidence limits) of the proportions of eyes with at least moderate or severe vision loss, respectively, were 59% (53% to 64.5%) and 34% (25% to 43%) at 1 year and 70% (64% to 76%) and 47% (40% to 54%) at 2 to 3 years; the overall pooled estimate of the percentage of eyes developing classic CNV at 1 year was 46% (39% to 54%).</p><p><b>CONCLUSION</b>A substantial number of patients with occult CNV from AMD will develop at least moderate visual loss at 1 year and severe visual loss within 3 years. However, visual acuity may remain stable in up to 30% of patients. These results may help us to understand the exact role of new therapies and in planning future trials.</p>