New Microbiologica最新文献

Management of heavily treatment experienced (HTE) people with HIV remains a challenge. Tailored antiretroviral therapy (ART) is needed in this fragile population who almost invariably harbor viral quasispecies with resistance-associated mutations (RAMs). The reference method for HIV genotypic resistance testing (GRT) has long been Sanger sequencing (SS), but next-generation sequencing (NGS), following recent progress in workflow and cost-effectiveness, is replacing SS because of higher sensitivity. From the PRESTIGIO Registry, we present a case of a 59-year-old HTE woman who failed darunavir/ritonavir plus raltegravir at low-viremia levels due mainly to high pill burden and poor adherence. NGS-GRT was performed on HIV-RNA at failure and the results were compared to all past SS-GRT data available (historical genotype). In this case, NGS-GRT did not detect any minority drug-resistant variants. After discussing several therapeutic options, the treatment was changed to dolutegravir 50 mg twice daily plus doravirine 100 mg once a day, based on clinical history, adherence issues, and pill burden, as well as the historical SS-GRT and the latest NGS-GRT results. At six months follow-up visit, the patient had HIV-RNA below 30 copies/ml and CD4+ T cell count increased from 673 cells/ mm3 to 688 cells/ mm3. Close follow-up of this patient is ongoing.

The intestinal microbiota plays a fundamental role in physiological homeostasis as well as in pathologic conditions. Hepatitis C virus is the leading cause of chronic liver diseases worldwide. The treatment of this infection has been revolutionized by the availability of direct-acting antiviral agents which guarantee a high rate (about 95%) of viral clearance. Few studies have assessed the change in the gut microbiota of patients treated with direct-acting antiviral agents against HCV, and many aspects still need to be clarified. The aim of the study was to evaluate the effects of antiviral therapy on gut microbiota. We enrolled patients with HCV-related chronic liver disease attending the Infectious Diseases Unit of the A.O.U. Federico II of Naples from January 2017 to March 2018 and treated with DAAs. For each patient, a fecal sample was collected and analyzed for the assessment of microbial diversity before the start of therapy and by SVR12 time. We excluded patients who had received antibiotics in the previous 6 months. Twelve patients were enrolled (6 male, 8 genotype 1 (1 subtype 1a), 4 genotype 2). Fibrosis scores were F0 in 1 patient, F2 in 1 patient, F3 in 4 patients and cirrhosis in the remaining 6 (all in Child-Pugh class A). All were treated with DAAs for 12 weeks (5 with Paritaprevir-Ombitasvir-Ritonavir-Dasabuvir, 3 with Sofosbuvir-Ledipasvir, 1 with Sofosbuvir-Ribavirin, 1 with Sofosbuvir-Daclatasvir, 1 with Sofosbuvir-Velpatasvir) and 100% achieved SVR12. In all patients, we observed a trend in reduction of potentially pathogenic microorganisms (i.e., Enterobacteriaceae). Furthermore, a trend of increase in α-diversity was observed in patients by SVR12 compared to baseline. This trend was markedly more evident in patients without liver cirrhosis than in those with cirrhosis. Our study shows that viral eradication obtained with DAA is associated with a trend in restoring the heterogeneity of α-diversity and in reducing the percentage of potentially pathogenic microbial species, although this benefit is less evident in patients with cirrhosis. Further studies with larger sample size are needed to confirm these data.

Since the outbreak of the 2019 pandemic coronavirus disease (COVID-19), great attention has been given to identifying the main clinical features of the disease. Identification of laboratory parameters able to classify patients based on their risk is mandatory to improve their clinical management. We retrospectively evaluated twenty-six laboratory tests measured in COVID-19 positive patients admitted to the hospital in March and April 2020 to find any correlation between their changes and the risk of death. We divided them into surviving and non-surviving patients. A total of 1587 patients were recruited, 854 males with median age of 71 (IQR 56-81) and 733 females with median age of 77 (IQR 61-87). On admission, death was found to be positively correlated with age (p=0.001), but not with sex (p=0.640) or with hospitalization in days (p=0.827). Brain natriuretic peptide (BNP), creatinine, C-reactive protein (CRP), INR, leukocyte count, lymphocyte count, neutrophil count, and procalcitonin (PCT) demonstrated a statistically significant difference between the two groups (p<0.001), suggesting their role as markers of disease severity; only lymphocyte count resulted as an independent risk factor for death.

Microbial biofilm is of paramount importance in the development of mucositis or peri-implantitis in patients with dental implants. This study was designed to investigate whether an electromagnetic field at high frequency waves directly applied on 33 titanium implants could remove experimentally-induced Enterococcus faecalis bacterial biofilm. A specially designed device (X-IMPLANT) was used to generate the electromagnetic field, with output power of 8 W, supply frequency (action/pause) 3/2s, and an output frequency of 625±5% kHz in plastic devices containing the biofilm-covered implants immersed in sterile saline. The bacterial biofilm on both treated and untreated control implants was quantitatively measured by phenol red-based Bio-Timer-Assay reagent. The kinetic analysis of the curves showed that the electrical treatment generated by the X-IMPLANT device completely removed the bacterial biofilm after 30 minutes of treatment (p<0.01). Elimination of the biofilm was also confirmed by chromatic observation in the macro-method. Our data seem to indicate that the procedure could be considered for clinical application in peri-implantitis to counteract bacterial biofilm on dental implants.

Currently, the infection of hypervirulent Klebsiella pneumoniae (hvKp) is becoming increasingly serious and the virulent mechanisms of hvKp are still not very clear. An effective gene-editing method for genes on hvKp virulence plasmid can help us reveal related virulent mechanisms. There are a few reports focusing on the methods mentioned above, however with certain limitations. In this work, we first constructed the pRE112-basing recombinant suicide plasmid to knock out or replace the genes in the hvKp virulence plasmid based on the principle of homology recombination. Results showed that the target virulent genes iucA, iucB, iroB, and rmpA2 on the hvKp virulence plasmid were scarlessly knocked out or replaced by marker genes, and mutant hvKp strains with the expected phenotypes were obtained. These indicated that we established an efficient gene-editing method for genes on hvKp virulence plasmid, which could help us explore the functions of these genes and reveal the virulent mechanisms of hvKp.

The effects of clinical symptoms, laboratory indicators, and comorbidity status of SARS-CoV-2-infected patients on the severity of disease and the risk of death were investigated. Questionnaires and electronic medical records of 371 hospitalized COVID-19 patients were used for data collection (demographics, clinical manifestation, comorbidities, laboratory data). Association among categorical variables was determined using Kolmogorov-Smirnov test (P-value ≤0.05). Median age of study population (249 males, 122 females) was 65 years. Roc curves analysis found that age ≥64 years and age ≥67 years are significant cut-offs identifying patients with more severe disease and mortality at 30 days. CRP values at cut-off ≥80.7 and ≥95.8 significantly identify patients with more severe disease and mortality. Patients with more severe disease and risk of death were significantly identified with platelet value at the cut-off ≤160,000, hemoglobin value at the cut-off ≤11.7, D-Dimer values ≥1383 and ≥1270, and with values of neutrophil granulocytes (≥8.2 and ≤2) and lymphocytes (≤2 and ≤2.4). Detailed clinical investigation suggests granulocytes together with lymphopenia may be a potential indicator for diagnosis. Older age, several comorbidities (cancer, cardiovascular diseases, hypertension) and more laboratory abnormalities (CRP, D-Dimer, platelets, hemoglobin) were associated with development of more severity and mortality among COVID-19 patients.

We report a case of a 26-year-old female who developed a brain abscess that was strongly suspected to be caused by Staphylococcus epidermidis, A. aphrophilus, and E. corrodens species. In general, A. aphrophilus and E. corrodens, members of the HACEK group (Haemophilus spp., Aggregatibacter spp., C. hominis, E. corrodens, and K. kingae), have been associated with the development of endocarditis, meningitis, sinusitis, otitis media, pneumonia, osteomyelitis, peritonitis, and wound infections. Cerebral abscesses are a rare manifestation of these bacteria; only a few cases are described in the literature, generally related to the diffusion of these organisms through the bloodstream after a dental procedure or a heart disease. Our case is unique because the rarity of the infection site appeared apparently in absence of risk factors. The patient underwent surgery to drain the abscess and was subsequently put on intravenous antibiotic treatment with ceftriaxone, vancomycin, and metronidazole. After 6 months, brain imaging revealed that the lesion had disappeared. The patient achieved excellent results with this approach.

Lactococcus species are micro-aerophilic Gram positive bacteria characterized by low virulence features and other biotechnological properties of industrial interest. They are thus widely employed in food fermentation processes. Despite its low pathogenic potential and food grade safety, L. lactis may, however, rarely cause infections, especially among immunocompromised hosts. Moreover, the growing complexity of patients implies increased detections of such infections. This said, there is a paucity of data concerning L. lactis infections from infusion of blood transfusion products. To our knowledge, this is the first case of L. lactis infection from transfusion of blood products, as observed in an 82-year-old Caucasian male undergoing weekly platelet and blood transfusion due to sustained severe thrombocytopenia. Albeit minimally pathogenic, L. lactis should be considered for thorough testing, especially in the case of human-derived infusion products such as platelets due to their storage requirements for extended times at room temperature and their use in immunocompromised and critically ill subjects.

Although progress has led to a drop in infections, meningitis still represents a threat worldwide, affecting some areas more than others. As a medical emergency, it requires prompt recognition and treatment. Moreover, diagnosis relies on invasive methods, while representing a tug-of-war with timely therapeutic interventions, since delays are burdened by mortality and life-long sequalae. While counterbalancing the overuse of antimicrobials, it is imperative to assess correct interventions in order to optimize treatments and reduce negative outcomes. Because the drop in mortality and consequences has been consistent, although not as impactful as with other vaccine-preventable diseases, the WHO has traced a roadmap detailing actions to reduce the meningitis burden by 2030. There are currently no updated guidelines, whereas novel diagnostic methods as well as pharmacological interventions are increasing, along with the shifting epidemiology. In light of the above, this paper wishes to summarize existing data and evidences and suggest potential novel solutions to a complex problem.

Drug-resistant tuberculosis (DR-TB) is a major global health challenge. In 2021, about one third of DR-TB patients worldwide were enrolled in treatment. In order to reach the targets set during by the 2018 UN General Assembly (UNGA) Political Declaration on Tuberculosis, a global effort must be made by both high- and low-incidence countries. Data concerning high-incidence countries are vast in the literature, but insufficient political attention has been paid in low-incidence countries to face this infectious threat. This review aims at providing an overview of DR-TB focused on different facets of DR-TB management. First, global and Italian data on the main at-risk populations for TB and DR-TB were gathered, together with the latest studies on the correlation between TB risk factors and the onset of drug resistance. Second, this review provides an analysis of obsolete Italian guidelines on the diagnosis and management of TB and DR-TB, highlighting the challenges that our country is currently facing to properly implement the latest international recommendations. Finally, some key suggestions are provided to design public health (PH) policies that can effectively tackle the DR-TB issue from a "global health" perspective.