Comparison of Methods in the Serologic Diagnosis of Cystic Echinococcosis.

PURPOSE: Cystic echinococcosis (CE) is caused by the larval form of Echinococcus granulosus. Clinical, radiologic, pathologic, and serologic findings should be evaluated together for the diagnosis of CE. The sensitivity and specificity oalf serologic tests may vary depending on the method used. In this study, we aimed to detect IgG antibodies specific to E. granulosus using indirect hemagglutination assay (IHA), enzyme-linked immunosorbent assay (ELISA), indirect fluorescent antibodies (IFA) and western blot (WB) tests. METHODS: In our study, the serum samples of 74 patients sent to our laboratory with suspicion of CE were studied using two different commercial IHA tests, ELISA, IFA and WB test. The test results were evaluated along with radiological findings and histopathological examinations, the latter being the gold standard. RESULTS: Of all the patients, 51 (69%) were female and 23 (31%) were male. There was a statistically significant difference between males and females (χ2 = 9.7, p = 0.002). Out of 74 patients, positivity rates for Siemens IHA, Fumouze IHA, ELISA, IFA and WB test were positive as 33 (44.6%), 35 (47.3%), 43 (58.1%), 42 (56.7%) and 38 (51.3%), respectively. The sensitivity and specificity of the tests were as follows: 66.67 and 2.31% for Siemens IHA; 70.83% and 96.15% for Fumouze IHA; 85.42%, and 88.46% for ELISA; 83.33% and 88.46% for IFA; 72.92% and 88.46% for WB test. CONCLUSION: There were statistically significant differences in between all five methods (p < 0,001). While the tests with the highest specificity was Fumouze IHA, the test with the highest sensitivity was the ELISA test. It was concluded that IHA and ELISA tests were more practical in practice because of their greater applicability.

Monoclonal outbreak of Ralstonia solanacearum catheter-related bloodstream infection associated with contaminated package of normal saline solution in a tertiary care hospital

Background/aim: Ralstonia solanacearum is a very rare cause of infection in humans. There is no described nosocomial outbreak due to R. solanacearum so far. We determined R. solanacearum as the source of catheter-related bloodstream infection (CRBSI) outbreak. Materials and methods: This outbreak analysis was carried out in a 1000-bed tertiary care university hospital in Turkey. The outbreak analysis included hematology, oncology, nephrology, gastroenterology wards, emergency department, and intensive care units. The first case with R. solanacearum CRBSI was detected on May 20, 2019 and R. solanacearum was isolated in catheter blood cultures in 34 patients until October 3, 2019 Results: Standard outbreak analysis procedures were applied. Culture samples were taken from the fluids administered via catheters. The cultures did not yield any bacteria. As a result of the investigation in storage area, it was found that there were leaks, air bubbles, and water drops inside the packaging of saline solutions. R. solanacearum was yielded in the cultures obtained from the surface of saline bags and the inner sides of plastic packings. To validate our hypothesis, a clonal analysis was performed using arbitrarily primed-PCR method and Sanger sequencing of the 16S rRNA gene for identification among isolates. All R. solanacearum isolates were monoclonal and identical. Conclusion: This is the first outbreak of R. solanacearum CRBSI described in a hospital setting. The source of the outbreak was a contamination in the surface of saline bags and the inner sides of plastic packings. Efficacy of an active surveillance system, accurate and rapid conduction of microbiological identification are essential for outbreak management.

Rose Bengal-Mediated Photodynamic Antimicrobial Treatment of Acanthamoeba Keratitis.

Purpose: To evaluate the in vivo efficacy of rose bengal (RB)-mediated photodynamic antimicrobial therapy (PDAT) for treatment of Acanthamoeba castellanii keratitis (AK). Materials and Methods: An animal (rabbit) AK model was successfully achieved via intrastromal inoculation of a suspension of A. castellanii cells and trophozoites. Prior to RB-PDAT (pre-treatment, day-5), the severity of the induced corneal infection was graded numerically for epithelial defects, stromal edema, neovascularity, and stromal opacity/infiltration. The right eyes of rabbits (n = 18) were divided equally into three groups (n = 6/group): control (no treatment); 0.1% RB+518 nm irradiation (5.4 J/cm2); and 0.2% RB+518 nm irradiation (5.4 J/cm2). On post-treatment day-5, animals were euthanized, after which corneal buttons were excised and submitted for real-time polymerase chain reaction (RT-PCR) analysis. Results: Post-treatment clinical scores of the 0.1 and 0.2% RB groups indicated significant improvement compared to control group scores (pre-treatment clinical scores; 5.17 ± 0.98, 7.50 ± 0.62, and 6.17 ± 0.70 and post-treatment clinical scores; 4.50 ± 0.56, (p = .043), 3.50 ± 0.99 (p = .039), 6.83 ± 1.66 (p = .34), respectively). RT-PCR analysis revealed that the mean cycle threshold (Ct) values were significantly higher in treated-group corneas compared to control-group corneas, with no significant differences between treated-groups (Mean Ct values; 34.33, 34.5, and 29.67 for 0.1 and 0.2% RB, and control groups). There was a statistically significant negative correlation between post-treatment clinical scores and Ct values (r = -0.474, p-value 0.047). Conclusions: Our results demonstrate that RB-PDAT is effective in decreasing the parasitic load and clinical severity of AK.