The Etiology, Antibiotic Therapy and Outcomes of Bacteremic Skin and Soft-Tissue Infections in Onco-Hematological Patients.

OBJECTIVES: to assess the current epidemiology, antibiotic therapy and outcomes of onco- hematological patients with bacteremic skin and soft-tissue infections (SSTIs), and to identify the risk factors for Gram-negative bacilli (GNB) infection and for early and overall mortality. METHODS: episodes of bacteremic SSTIs occurring in cancer patients at two hospitals were prospectively recorded and retrospectively analyzed. RESULTS: Of 164 episodes of bacteremic SSTIs, 53% occurred in patients with solid tumors and 47% with hematological malignancies. GNB represented 45.5% of all episodes, led by Pseudomonas aeruginosa (37.8%). Multidrug resistance rate was 16%. Inadequate empirical antibiotic therapy (IEAT) occurred in 17.7% of episodes, rising to 34.6% in those due to resistant bacteria. Independent risk factors for GNB infection were corticosteroid therapy and skin necrosis. Early and overall case-fatality rates were 12% and 21%, respectively. Risk factors for early mortality were older age, septic shock, and IEAT, and for overall mortality were older age, septic shock and resistant bacteria. CONCLUSIONS: GNB bacteremic SSTI was common, particularly if corticosteroid therapy or skin necrosis. IEAT was frequent in resistant bacteria infections. Mortality occurred mainly in older patients with septic shock, resistant bacteria and IEAT. These results might guide empirical antibiotic therapy in this high-risk population.

Nocardia Infections in the Immunocompromised Host: A Case Series and Literature Review.

Nocardia is primarily considered an opportunistic pathogen and affects patients with impaired immune systems, solid-organ transplant recipients (SOTRs), and patients with haematologic malignancies. We present the cases of six patients diagnosed with nocardiosis at our center in the last two years, describing the various predisposing conditions alongside the clinical manifestation, the diagnostic workup, and the treatment course. Moreover, we propose a brief literature review on Nocardia infections in the immunocompromised host, focusing on SOTRs and haematopoietic stem cell transplantation recipients and highlighting risk factors, clinical presentations, the diagnostic tools available, and current treatment and prophylaxis guidelines.

Pneumocystis jirovecii pneumonia in HIV-negative patients, a frequently overlooked problem. A case series from a large Italian center.

BACKGROUND AND OBJECTIVES: Pneumocystis jirovecii pneumonia (PCP) still has substantial morbidity and mortality. For non-HIV patients, the course of infection is severe, and management guidelines are relatively recent. We collected all PCP cases (European Organization for Research and Treatment of Cancer criteria) diagnosed in HIV-negative adult inpatients in 2019-2020 at our center in northern Italy. RESULTS: Of 20 cases, nine had microbiologic evidence of probable (real-time polymerase chain reaction, RT-PCR) and 11 proven (immunofluorescence) PCP on respiratory specimens. Half were female; the median age was 71.5 years; 14 of 20 patients had hematologic malignancies, five had autoimmune/hyperinflammatory disorders, and one had a solid tumor. RT-PCR cycle threshold (Ct) was 24-37 for bronchoalveolar lavage (BAL) and 32-39 for sputum; Ct was 24-33 on BAL proven cases. Of 20 cases, four received additional diagnoses on BAL. At PCP diagnosis, all patients were not on anti-pneumocystis prophylaxis. We retrospectively assessed prophylaxis indications: 9/20 patients had a main indication, 5/9 because of prednisone treatment ≥ 20 mg (or equivalents) for ≥4 weeks. All patients underwent antimicrobial treatment according to guidelines; 18/20 with concomitant corticosteroids. A total of 4/20 patients died within 28 days from diagnosis. CONCLUSION: Despite appropriate treatment, PCP is still associated to high mortality (20%) among non-HIV patients. Strict adherence to prophylaxis guidelines, awareness of gray areas, and prompt diagnosis can help manage this frequently overlooked infection.

Could Long-Acting Cabotegravir-Rilpivirine Be the Future for All People Living with HIV? Response Based on Genotype Resistance Test from a Multicenter Italian Cohort.

Long-acting (LA) formulations have been designed to improve the quality of life of people with HIV (PWH) by maintaining virologic suppression. However, clinical trials have shown that patient selection is crucial. In fact, the HIV-1 resistance genotype test and the Body Mass Index of individual patients assume a predominant role in guiding the choice. Our work aimed to estimate the patients eligible for the new LA therapy with cabotegravir (CAB) + rilpivirine (RPV). We selected, from the Antiviral Response Cohort Analysis (ARCA) database, all PWH who had at least one follow-up in the last 24 months. We excluded patients with HBsAg positivity, evidence of non-nucleoside reverse transcriptase inhibitor (except K103N) and integrase inhibitor mutations, and with a detectable HIV-RNA (>50 copies/mL). Overall, 4103 patients are currently on follow-up in the ARCA, but the eligible patients totaled 1641 (39.9%). Among them, 1163 (70.9%) were males and 1399 were Caucasian (85.3%), of which 1291 (92%) were Italian born. The median length of HIV infection was 10.2 years (IQR 6.3-16.3) with a median nadir of CD4 cells/count of 238 (106-366) cells/mm3 and a median last available CD4 cells/count of 706 (509-944) cells/mm3. The majority of PWH were treated with a three-drug regimen (n = 1116, 68%). Among the 525 (30.3%) patients treated with two-drug regimens, 325 (18.1%) were treated with lamivudine (3TC) and dolutegravir (DTG) and only 84 (5.1%) with RPV and DTG. In conclusion, according to our snapshot, roughly 39.9% of virologically suppressed patients may be suitable candidates for long-acting CAB+RPV therapy. Therefore, based on our findings, many different variables should be taken into consideration to tailor the antiretroviral treatment according to different individual characteristics.

Antiviral Treatments for Influenza.

Influenza is an acute respiratory illness caused by the influenza A, B, and C viruses. It can occur in local outbreaks or seasonal epidemics, with possibility to spread worldwide in a pandemic when a novel strain with significant antigenic differences emerges. During the past years, several new drugs have become available, with different accessibility related to specific countries' approval. We have conducted a review of literature, analyzing the most recent data on efficacy and safety of drugs currently available to treat influenza, with a particular attention toward special populations. Efficacy and safety profile of neuraminidase inhibitors (oseltamivir, zanamivir, laninamivir, peramivir) and recently approved cap-dependent endonuclease inhibitor baloxavir marboxil are reported in literature, but still little information is available about special populations such as critically ill patients and patients with a history of chronic respiratory disease. Moreover, the emergence of strains with reduced or no susceptibility to current drugs is a matter of concern, suggesting the need of constant monitoring of viral variants.

T-Cell Exhaustion in Mycobacterium tuberculosis and Nontuberculous Mycobacteria Infection: Pathophysiology and Therapeutic Perspectives.

Immune exhaustion is a condition associated with chronic infections and cancers, characterized by the inability of antigen-specific T cells to eliminate the cognate antigen. Exhausted T cells display a peculiar phenotypic profile and exclusive functional characteristics. Immune exhaustion has been described in patients with Mycobacterium tuberculosis infection, and cases of tuberculosis reactivation have been reported in those treated with immune checkpoint inhibitors, drugs able to re-establish T-cells' function. Exhausted T CD8+ cells' profile has also been described in patients with infection due to nontuberculous mycobacteria. In this review, we initially provide an overview of the mechanisms leading to immune exhaustion in patients infected by Mycobacterium tuberculosis and nontuberculous mycobacteria. We then dissect the therapeutic perspectives related to immune checkpoint blockade in patients with these infections.

Mucormycosis in CAPA, a Possible Fungal Super-Infection.

The occurrence of pulmonary fungal superinfection due to Aspergillus spp. in patients with COVID-19 is a well-described complication associated with significant morbidity and mortality. This can be related to a directed effect of the virus and to the immunosuppressive role of the therapies administered for the disease. Here, we describe the first case of pulmonary infection due to Mucorales occurring in a patient with a concomitant diagnosis of COVID-19-associated pulmonary aspergillosis.

Immune Checkpoint Inhibitors in People Living with HIV/AIDS: Facts and Controversies.

Immune checkpoint inhibitors (ICIs) are reshaping the landscape of cancer treatment, redefining the prognosis of several tumors. They act by restoring the cytotoxic activity of tumor-specific T lymphocytes that are in a condition of immune exhaustion. The same condition has been widely described in chronic HIV infection. In this review, we dissect the role of ICIs in people living with HIV/AIDS (PLWHIV). First, we provide an overview of the immunologic scenario. Second, we discuss the possible use of ICIs as adjuvant treatment of HIV to achieve elimination of the viral reservoir. Third, we examine the influence of HIV infection on ICI safety and effectiveness. Finally, we describe how the administration of ICIs impacts opportunistic infections.

The Interplay between Gut Microbiota and the Immune System in Liver Transplant Recipients and Its Role in Infections.

Liver transplantation (LT) is a life-saving strategy for patients with end-stage liver disease, hepatocellular carcinoma, and acute liver failure. LT success can be hampered by several short-term and long-term complications. Among them, bacterial infections, especially those due to multidrug-resistant germs, are particularly frequent, with a prevalence between 19 and 33% in the first 100 days after transplantation. In the last decades, a number of studies have highlighted how the gut microbiota (GM) is involved in several essential functions to ensure intestinal homeostasis, becoming one of the most important virtual metabolic organs. The GM works through different axes with other organs, and the gut-liver axis is among the most relevant and investigated ones. Any alteration or disruption of the GM is defined as dysbiosis. Peculiar phenotypes of GM dysbiosis have been associated with several liver conditions and complications, such as chronic hepatitis, fatty liver disease, cirrhosis, and hepatocellular carcinoma. Moreover, there is growing evidence of the crucial role of the GM in shaping the immune response, both locally and systemically, against pathogens. This paves the way to the manipulation of the GM as a therapeutic instrument to modulate infectious risk and outcome. In this minireview, we provide an overview of the current understanding of the interplay between the gut microbiota and the immune system in liver transplant recipients and the role of the former in infections.

Mini Review Immunological Consequences of Immunization With COVID-19 mRNA Vaccines: Preliminary Results.

Background: BNT162b2 and mRNA-1273 are the two recently approved mRNA-based vaccines against COVID-19 which has shown excellent safety and efficacy. Preliminary data about specific and neutralizing antibodies is available covering the first 100 days after vaccination. Methods: We reviewed all the publications regarding the immunologic consequences of BNT162b2 and mRNA-1273 vaccination. A summary of specific antibodies concentration and neutralizing antibodies titers elicited by each vaccine is provided. Results: BNT162b2 and mRNA-1273 displayed a reassuring safety and efficacy profile, with the latter above 94%. They can elicit specific antibodies titers and neutralizing antibodies concentrations that are far superior from those observed among COVID-19 human convalescent serum, across a wide span of age, for at least 100 days after vaccination. Moreover, the vaccine-induced T cellular response is oriented toward a TH1 response and no evidence of vaccine-enhanced disease have been reported. Discussion: BNT162b2 and mRNA-1273 can elicit specific antibodies titers and neutralizing antibodies concentrations above those observed among COVID-19 human convalescent serum in the first 100 days after vaccination. Data about vaccine efficacy in those with previous COVID-19 or immunocompromised is still limited.

Anakinra combined with methylprednisolone in patients with severe COVID-19 pneumonia and hyperinflammation: An observational cohort study.

BACKGROUND: Immunomodulants have been proposed to mitigate severe acute respiratory syndrome coronavirus 2-induced cytokine storm, which drives acute respiratory distress syndrome in coronavirus disease 2019 (COVID-19). OBJECTIVE: We sought to determine efficacy and safety of the association of IL-1 receptor antagonist anakinra plus methylprednisolone in severe COVID-19 pneumonia with hyperinflammation. METHODS: A secondary analysis of prospective observational cohort studies was carried out at an Italian tertiary health care facility. COVID-19 patients consecutively hospitalized (February 25, 2020, to March 30, 2020) with hyperinflammation (ferritin ≥1000 ng/mL and/or C-reactive protein >10 mg/dL) and respiratory failure (oxygen therapy from 0.4 FiO2 Venturi mask to invasive mechanical ventilation) were evaluated to investigate the effect of high-dose anakinra plus methylprednisolone on survival. Patients were followed from study inclusion to day 28 or death. Crude and adjusted (sex, age, baseline PaO2:FiO2 ratio, Charlson index, baseline mechanical ventilation, hospitalization to inclusion lapse) risks were calculated (Cox proportional regression model). RESULTS: A total of 120 COVID-19 patients with hyperinflammation (median age, 62 years; 80.0% males; median PaO2:FiO2 ratio, 151; 32.5% on mechanical ventilation) were evaluated. Of these, 65 were treated with anakinra and methylprednisolone and 55 were untreated historical controls. At 28 days, mortality was 13.9% in treated patients and 35.6% in controls (Kaplan-Meier plots, P = .005). Unadjusted and adjusted risk of death was significantly lower for treated patients compared with controls (hazard ratio, 0.33, 95% CI, 0.15-0.74, P = .007, and HR, 0.18, 95% CI, 0.07-0.50, P = .001, respectively). No significant differences in bloodstream infections or laboratory alterations were registered. CONCLUSIONS: Treatment with anakinra plus methylprednisolone may be a valid therapeutic option in COVID-19 patients with hyperinflammation and respiratory failure, also on mechanical ventilation. Randomized controlled trials including the use of either agent alone are needed to confirm these results.

Early Phases of COVID-19 Are Characterized by a Reduction in Lymphocyte Populations and the Presence of Atypical Monocytes.

Background: Severe acute respiratory syndrome coronavirus 2 is a recently discovered pathogen responsible of coronavirus disease 2019 (COVID-19). The immunological changes associated with this infection are largely unknown. Methods: We evaluated the peripheral blood mononuclear cells profile of 63 patients with COVID-19 at diagnosis. We also assessed the presence of association with inflammatory biomarkers and the 28-day mortality. Results: Lymphocytopenia was present in 51 of 63 (80.9%) patients, with a median value of 720 lymphocytes/µl (IQR 520-1,135). This reduction was mirrored also on CD8+ (128 cells/µl, IQR 55-215), natural killer (67 cells/µl, IQR 35-158) and natural killer T (31 cells/µl, IQR 11-78) cells. Monocytes were preserved in total number but displayed among them a subpopulation with a higher forward and side scatter properties, composed mainly of cells with a reduced expression of both CD14 and HLA-DR. Patients who died in the 28 days from admission (N=10, 15.9%), when compared to those who did not, displayed lower mean values of CD3+ (337.4 cells/µl vs 585.9 cells/µl; p=0.028) and CD4+ cells (232.2 cells/µl vs 381.1 cells/µl; p=0.042) and an higher percentage of CD8+/CD38+/HLA-DR+ lymphocytes (13.5% vs 7.6%; p=0.026). Discussion: The early phases of COVID-19 are characterized by lymphocytopenia, predominance of Th2-like lymphocytes and monocytes with altered immune profile, which include atypical mononuclear cells.

Multidrug-Resistant Gram-Negative Bacteria Decolonization in Immunocompromised Patients: A Focus on Fecal Microbiota Transplantation.

Antimicrobial resistance is an important issue for global health; in immunocompromised patients, such as solid organ and hematological transplant recipients, it poses an even bigger threat. Colonization by multidrug-resistant (MDR) bacteria was acknowledged as a strong risk factor to subsequent infections, especially in individuals with a compromised immune system. A growing pile of studies has linked the imbalance caused by the dominance of certain taxa populating the gut, also known as intestinal microbiota dysbiosis, to an increased risk of MDR bacteria colonization. Several attempts were proposed to modulate the gut microbiota. Particularly, fecal microbiota transplantation (FMT) was successfully applied to treat conditions like Clostridioides difficile infection and other diseases linked to gut microbiota dysbiosis. In this review we aimed to provide a look at the data gathered so far on FMT, focusing on its possible role in treating MDR colonization in the setting of immunocompromised patients and analyzing its efficacy and safety.

Sensitivity of SARS-CoV-2 Detection With Nasopharyngeal Swabs.

Background: SARS-CoV-2-infected subjects have been proven contagious in the symptomatic, pre-symptomatic and asymptomatic phase. The identification of these patients is crucial in order to prevent virus circulation. No reliable data on the sensitivity of nasopharyngeal swabs (NPS) are available because of the lack of a shared reference standard to identify SARS-CoV-2 infected patients. The aim of our study was to collect data on patients with a known diagnosis of COVID-19 who underwent serial testing to assess NPS sensitivity. Methods: The study was a multi-center, observational, retrospective clinical study with consecutive enrollment. We enrolled patients who met all of the following inclusion criteria: clinical recovery, documented SARS-CoV-2 infection (≥1 positive rRT-PCR result) and ≥1 positive NPS among the first two follow-up swabs. A positive NPS not preceded by a negative nasopharyngeal swab collected 24-48 h earlier was considered a true positive. A negative NPS followed by a positive NPS collected 24-48 h later was regarded as a false negative. The primary outcome was to define sensitivity of SARS-CoV-2 detection with NPS. Results: Three hundred and ninety three NPS were evaluated in 233 patients; the sensitivity was 77% (95% CI, 73 to 81%). Sensitivity of the first follow-up NPS (n = 233) was 79% (95% CI, 73 to 84%) with no significant variations over time. We found no statistically significant differences in the sensitivity of the first follow-up NPS according to time since symptom onset, age, sex, number of comorbidities, and onset symptoms. Conclusions: NPS utility in the diagnostic algorithm of COVID-19 should be reconsidered.

Hepatitis C virus-related factors associated WITH cognitive performance in HIV-HCV-coinfected patients.

The contribution of HCV-related variables to cognitive impairment in HIV-HCV-coinfected patients has been poorly investigated. We selected HIV-HCV-coinfected patients undergoing cognitive examination (exploring memory, language, speed of mental processing and fine motor function) at three clinical centres. Cognitive performance was evaluated using Z-transformed scores. Logistic regression analysis was used to investigate variables associated to cognitive impairment (defined as a composite Z-score ≤ - 1). Overall, 146 HIV-HCV-coinfected patients were enrolled. Median HCV-RNA was 6.2logU/mL. HCV genotype 1a/b was the most represented (53.4%). Liver fibrosis was mild (Fib4 ≤ 1.45) in the majority of patients (44.5%). Global cognitive impairment was diagnosed in 35 (24%) subjects. Exploring each domain, a higher proportion of impairment was observed for memory (37%) followed by speed of mental processing (32.2%), fine motor functioning (24%) and language (18.5%). Among HCV-related variables, the duration of HCV infection was independently associated with global cognitive impairment (aOR 1.13 per +1 year, p = 0.016) and abnormal speed of mental processing (aOR 1.16 per +1 year, p = 0.001), while higher HCV-RNA was independently associated to fine motor functioning impairment (aOR 1.98 per +1log, p = 0.037). HCV genotype, fibrosis stage, transaminases or bilirubin levels were not related to cognitive performance. Of note, integrase inhibitor (InSTI) use was independently associated to a pathological performance in fine motor functioning (aOR 3.34, p = 0.035) and memory (aOR 3.70, p = 0.014). In conclusion, the duration of HCV infection and HCV-RNA load showed an association with cognitive impairment, suggesting a role of hepatitis-related factors in the development of cognitive disorders in HIV-HCV-coinfected patients. The association between InSTI use and altered cognitive performance should prompt investigations about potential neurotoxicity of these drugs.

Characterisation of an inclusion complex between cladribine and 2-hydroxypropyl-beta-cyclodextrin.

Parenterally administered cladribine (2-chloro-2'-deoxyadenosine) has demonstrated promising efficacy and safety in clinical trials in patients with multiple sclerosis (MS). An oral formulation of this small molecule would be an attractive option for patients. Here, we describe the chemical characterisation of the inclusion complex between cladribine and the drug carrier molecule 2-hydroxypropyl-beta-cyclodextrin (2-HP-beta-CD). Several techniques were used to analyse the complex both in solution and in the solid state. These analyses provided evidence that the inclusion complex cannot be simply reduced to the sum of the two species, as it shows behaviour different from that of the physical mixture of the two components. Furthermore, solution nuclear magnetic resonance spectroscopy demonstrated the existence of an inclusion complex between cladribine and 2-HP-beta-CD. Importantly, analysis of a tablet formulation demonstrated that the chemical characteristics of the inclusion complex are not affected by the manufacturing process, and that the complex is stable during storage. This tablet formulation is currently under investigation for the treatment of patients with MS.

A kinetic study of the conjugate addition of benzenethiol to cyclic enones catalyzed by a nonsymmetrical uranyl-salophen complex.

The Et3N-assisted addition of benzenethiol to enones in chloroform is catalyzed with high turnover efficiency by the phenyl-substituted uranyl-salophen compound 3. Catalytic data show a close adherence to a quatermolecular mechanism involving reaction of a base-activated thiol with a reversibly formed complex of enone and metal catalyst, with a complication of product inhibition due to the formation of a product-catalyst complex. The role of the binding energy made available by interactions with the aromatic sidearm of the catalyst is discussed in terms of catalyst-substrate and catalyst-transition state complementarity.

Rhodium-mediated stereoselective polymerization of "carbenes".

Unprecedented rhodium-catalyzed stereoselective polymerization of "carbenes" from ethyl diazoacetate (EDA) to give high molecular mass poly(ethyl 2-ylidene-acetate) is described. The mononuclear, neutral [(N,O-ligand)M(I)(cod)] (M = Rh, Ir) catalytic precursors for this reaction are characterized by (among others) single-crystal X-ray diffraction. These species mediate formation of a new type of polymers from EDA: carbon-chain polymers functionalized with a polar substituent at each carbon of the polymer backbone. The polymers are obtained as white powders with surprisingly sharp NMR resonances. Solution and solid state NMR data for these new polymers reveal a highly stereoregular polymer, with a high degree of crystallinity. The polymer is likely syndiotactic. Material properties are very different from those of atactic poly(diethyl fumarate) polymer obtained by radical polymerization of diethyl fumarate. Other diazoacetates are also polymerized. Further studies are underway to reveal possible applications of these new materials.

"Oscillating" metallocene catalysts: what stops the oscillation?

The 150 MHz (13)C NMR microstructural analysis of polypropylene samples produced with two representative "oscillating" metallocene catalysts of largely different steric hindrance, namely [(2-(3,5-di-tert-butyl-4-methoxyphenyl)indenyl)(2)ZrP](+) and [(2-phenylindenyl)(2)ZrP](+) (P = polymeryl), and the implications on the origin of the stereocontrol are presented and discussed in detail. The original mechanistic proposal of an "oscillation" between a rac-like (isotactic-selective) and a meso-like (nonstereoselective) conformation cannot explain the observed polymer configuration. The isotactic-stereoblock nature of the polymers obtained with the former catalyst proves unambiguously that the active cation "oscillates" between the two enantiomorphous rac-like conformations at an average frequency that, even at high propene concentration, is only slightly lower than that of monomer insertion. The less-hindered [(2-phenylindenyl)(2)ZrP](+) gives instead a largely stereoirregular polypropylene, which is the logical consequence of a faster ligand rotation; however, depending on the use conditions (in particular, on the nature of the cocatalyst and the polarity of the solvent), the polymerization products may also contain appreciable amounts of a fairly isotactic fraction. The peculiar microstructure of this fraction, with isotactic blocks of the same relative configuration spanned by very short atactic ones, rules out the possibility that the latter are due to an active species in meso-like conformation and points rather to a conformationally "locked" rac-like species with restricted ring mobility. The hypothesis of a stereorigidity induced by the proximity to a counteranion, which would play the role of the interannular bridge in the rac-bis(indenyl) ansa-metallocenes, was tested by computer modeling on a [rac-(2-phenylindenyl)(2)ZrMe(C(3)H(6))][B(C(6)F(5))(4)] ion couple and found viable.