Derailed cytokine and immune cell networks account for organ damage and clinical severity of COVID-19 [1][2][3][4] . Here we show that SARS-CoV-2, like other viruses, evokes cellular senescence as a primary stress response in infected cells. Virus-induced senescence (VIS) is indistinguishable from other forms of cellular senescence and accompanied by a senescence-associated secretory phenotype (SASP), composed of pro-inflammatory cytokines, extracellular matrix-active factors and pro-coagulatory mediators [5][6][7] . COVID-19 patients displayed markers of senescence in their airway mucosa in situ and elevated serum levels of SASP factors. Mirroring COVID-19 hallmark features such as macrophage and neutrophil infiltration, endothelial damage and widespread thrombosis in affected lung tissue 1,8,9 , in vitro assays demonstrated macrophage activation with SASP-reminiscent secretion, complement lysis and SASP-amplifying secondary senescence of endothelial cells, neutrophil extracellular trap (NET) formation as well as activation of platelets and the clotting cascade in response to supernatant of VIS cells, including SARS-CoV-2-induced senescence. Senolytics such as Navitoclax and Dasatinib/Quercetin selectively eliminated VIS cells, mitigated COVID-19-reminiscent lung disease and reduced inflammation in SARS-CoV-2-driven hamster and mouse models. Our findings mark VIS as pathogenic trigger of COVID-19-related cytokine escalation and organ damage, and suggest senolytic targeting of virus-infected cells as a novel treatment option against SARS-CoV-2 and perhaps other viral infections.The pandemic human pathogenic SARS-CoV-2 coronavirus causes upper respiratory infections and subsequently COVID-19 lung disease that may get further complicated by septic multi-organ failure and comes with significant mortality 10,11 . Escalating immune activation with massive cytokine release seems to drive severe COVID-19 1-3 , possibly more than the virus infection itself. Mechanisms of viral
Chronic pulmonary aspergillosis (CPA) is a recognized complication of pulmonary tuberculosis (TB). In 2015, the World Health Organization reported 2.2 million new cases of nonbacteriologically confirmed pulmonary TB; some of these patients probably had undiagnosed CPA. In October 2016, the Global Action Fund for Fungal Infections convened an international expert panel to develop a case definition of CPA for resource-constrained settings. This panel defined CPA as illness for >3 months and all of the following: 1) weight loss, persistent cough, and/or hemoptysis; 2) chest images showing progressive cavitary infiltrates and/or a fungal ball and/or pericavitary fibrosis or infiltrates or pleural thickening; and 3) a positive Aspergillus IgG assay result or other evidence of Aspergillus infection. The proposed definition will facilitate advancements in research, practice, and policy in lower- and middle-income countries as well as in resource-constrained settings.
The substantial decline in the Pneumocystis jirovecii pneumonia (PCP) incidence in HIV-infected patients after the introduction of antiretroviral therapy (ART) in resource-rich settings and the growing number of non-HIV-infected immunocompromised patients at risk leads to considerable epidemiologic changes with clinical, diagnostic, and treatment consequences for physicians. HIV-infected patients usually develop a subacute course of disease, while non-HIV-infected immunocompromised patients are characterized by a rapid disease progression with higher risk of respiratory failure and higher mortality. The main symptoms usually include exertional dyspnea, dry cough, and subfebrile temperature or fever. Lactate dehydrogenase may be elevated. Typical findings on computed tomography scans of the chest are bilateral ground-glass opacities with or without cystic lesions, which are usually associated with the presence of AIDS. Empiric treatment should be initiated as soon as PCP is suspected. Bronchoalveolar lavage has a higher diagnostic yield compared to induced sputum. Immunofluorescence is superior to conventional staining. A combination of different diagnostic tests such as microscopy, polymerase chain reaction, and (1,3)-β-D-glucan is recommended. Trimethoprim/sulfamethoxazole for 21 days is the treatment of choice in adults and children. Alternative treatment regimens include dapsone with trimethoprim, clindamycin with primaquine, atovaquone, or pentamidine. Patients with moderate to severe disease should receive adjunctive corticosteroids. In newly diagnosed HIV-infected patients with PCP, ART should be initiated as soon as possible. In non-HIV-infected immunocompromised patients, improvement of the immune status should be discussed (e.g., temporary reduction of immunosuppressive agents). PCP prophylaxis is effective and depends on the immune status of the patient and the underlying immunocompromising disease.
The high clinical mortality and economic burden posed by invasive fungal infections (IFIs), along with significant agricultural crop loss caused by various fungal species, has resulted in the widespread use of antifungal agents. Selective drug pressure, fungal attributes, and host- and drug-related factors have counteracted the efficacy of the limited systemic antifungal drugs and changed the epidemiological landscape of IFIs. Species belonging to Candida, Aspergillus, Cryptococcus, and Pneumocystis are among the fungal pathogens showing notable rates of antifungal resistance. Drug-resistant fungi from the environment are increasingly identified in clinical settings. Furthermore, we have a limited understanding of drug class-specific resistance mechanisms in emerging Candida species. The establishment of antifungal stewardship programs in both clinical and agricultural fields and the inclusion of species identification, antifungal susceptibility testing, and therapeutic drug monitoring practices in the clinic can minimize the emergence of drug-resistant fungi. New antifungal drugs featuring promising therapeutic profiles have great promise to treat drug-resistant fungi in the clinical setting. Mitigating antifungal tolerance, a prelude to the emergence of resistance, also requires the development of effective and fungal-specific adjuvants to be used in combination with systemic antifungals.
Chronic pulmonary aspergillosis (CPA) complicates conditions including tuberculosis, chronic obstructive pulmonary disease and sarcoidosis, and is associated with high morbidity and mortality. Surgical cure should be considered where feasible; however, many patients are unsuitable for surgery due to extensive disease or poor respiratory function. Azoles are the only oral drug with anti-Aspergillus activity and itraconazole and voriconazole are considered as first-line drugs. A randomized controlled trial demonstrated improvement or stability in three-quarters of patients given 6 months of itraconazole, but a quarter relapsed on stopping therapy. Long-term treatment may therefore be required in some cases. Itraconazole, voriconazole and posaconazole require therapeutic drug monitoring. No published data are yet available for isavuconazole. Adverse drug effects of azoles are common, including peripheral neuropathy, heart failure, elevated liver enzymes, QTc prolongation and sun sensitivity. Many serious drug-drug interactions occur, including major interactions with rifamycins, simvastatin, warfarin, clopidogrel, immunosuppressant drugs like sirolimus. Furthermore, drug resistance occurs, including cross-resistance to all azoles, but the true prevalence is not yet determined. Intravenous therapy is possible with echinocandins or amphotericin B, but long-term use is challenging. Hemoptysis complicates CPA and can be fatal. Tranexamic acid should be given acutely to reduce bleeding. Bronchial artery embolization can stop acute bleeds. In some circumstances, emergency surgery may be necessary to resect the source of the bleed. Current CPA treatments can be beneficial but have many drawbacks. New oral anti-Aspergillus agents are needed, along with optimization of currently available treatments.
In recent decades, important advances have been made in the diagnosis and treatment of invasive aspergillosis (IA) and mucormycosis. One of these advances has been the introduction of isavuconazole, a second-generation broad spectrum triazole with a favorable pharmacokinetic and safety profile and few drug–drug interactions. Phase III trials in patients with IA and mucormycosis demonstrated that isavuconazole has similar efficacy to voriconazole for the treatment of IA (SECURE trial) and liposomal amphotericin B for the treatment of mucormycosis (VITAL trial with subsequent case–control analysis) and a favorable safety profile with significantly fewer ocular, hepatobiliary, and skin and soft tissue adverse events compared to voriconazole. As a result, recent IA guidelines recommend isavuconazole (together with voriconazole) as gold standard treatment for IA in patients with underlying hematological malignancies. In contrast to liposomal amphotericin B, isavuconazole can be safely administered in patients with reduced renal function and is frequently used for the treatment of mucormycosis in patients with reduced renal function. Updated guidelines on mucormycosis are needed to reflect the current evidence and give guidance on the use of isavuconazole for mucormycosis. Studies are needed to evaluate the role of isavuconazole for 1) anti-mold prophylaxis in high-risk patients, 2) salvage treatment for IA and mucormycosis, and 3) treatment for other mold infections such as Scedosporium apiospermum.
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