Infectious Disease

Infectious Disease Publications

Harris CK, Christensen BB, Kwan M, Foreman RK, Stagner AM. Pseudomonas species may appear strikingly filamentous in tissue sections: an important consideration for surgical pathologists and a reminder of the utility of modified silver impregnation methods. Histopathology 2022;Abstract
INTRODUCTION: Although tissue culture is the gold standard for diagnosing infection, histologic examination of surgically resected tissue can be a critical component in the diagnosis of tissue infection. The goal of this brief report is to alert surgical pathologists that Pseudomonas species can appear strikingly filamentous histologically and may somewhat mimic the appearance of filamentous bacteria, such Actinomyces or Nocardia, or thin fungal hyphae. A secondary aim is to raise awareness that Pseudomonas can sometimes only be identified histologically through the use of a modified silver impregnation method (Steiner stain). METHODS: Five cases of filamentous Pseudomonas were encountered in three different surgical pathology subspecialities (ophthalmic pathology, cardiovascular pathology, and dermatopathology) over a 1-year period. All cases were of formalin-fixed, paraffin-embedded tissue, stained using hematoxylin & eosin (H&E) and multiple histochemical stains. Four cases grew Pseudomonas aeruginosa in culture and in the fifth case, a non-aeruginosa species was detected using polymerase chain reaction-based methods. RESULTS: Five cases of markedly filamentous-appearing Pseudomonas were identified in five different tissue sites: vascular graft, enucleation (whole eye) specimen, scleral biopsy, soft tissue excision, and skin punch biopsy. In one of the five cases were the organisms seen on H&E and in only two of the five were the organisms seen on Brown-Hopps stain. In all five cases, the organisms were identified on Steiner stain. DISCUSSION: Pseudomonas can appear markedly filamentous. If Pseudomonas or other bacterial infection is suspected, the surgical pathologist would be advised to employ the Steiner stain to most consistently detect the organisms.
Dave TV, Nair AG, Joseph J, Freitag SK. Immunopathology of COVID-19 and its implications in the development of rhino-orbital-cerebral mucormycosis: a major review. Orbit 2022;:1-10.Abstract
PURPOSE: To present a literature review on various immunopathologic dysfunctions following COVID-19 infection and their potential implications in development of rhino-orbital-cerebral mucormycosis (ROCM). METHODS: A literature search was performed via Google Scholar and PubMed with subsequent review of the accompanying references. Analogies were drawn between the immune and physiologic deviations caused by COVID-19 and the tendency of the same to predispose to ROCM. RESULTS: Sixty-two articles were reviewed. SARS-CoV-2 virus infection leads to disruption of epithelial integrity in the respiratory passages, which may be a potential entry point for the ubiquitous Mucorales to become invasive. COVID-19 related GRP78 protein upregulation may aid in spore germination and hyphal invasion by Mucorales. COVID-19 causes interference in macrophage functioning by direct infection, a tendency for hyperglycemia, and creation of neutrophil extracellular traps. This affects innate immunity against Mucorales. Thrombocytopenia and reduction in the number of natural killer (NK) cells and infected dendritic cells is seen in COVID-19. This reduces the host immune response to pathogenic invasion by Mucorales. Cytokines released in COVID-19 cause mitochondrial dysfunction and accumulation of reactive oxygen species, which cause oxidative damage to the leucocytes. Hyperferritinemia also occurs in COVID-19 resulting in suppression of the hematopoietic proliferation of B- and T-lymphocytes. CONCLUSIONS: COVID-19 has a role in the occurrence of ROCM due to its effects at the entry point of the fungus in the respiratory mucosa, effects of the innate immune system, creation of an environment of iron overload, propagation of hyperglycemia, and effects on the adaptive immune system.
Ismail AM, Saha A, Lee JS, Painter DF, Chen Y, Singh G, Condezo GN, Chodosh J, San Martín C, Rajaiya J. RANBP2 and USP9x regulate nuclear import of adenovirus minor coat protein IIIa. PLoS Pathog 2022;18(6):e1010588.Abstract
As intracellular parasites, viruses exploit cellular proteins at every stage of infection. Adenovirus outbreaks are associated with severe acute respiratory illnesses and conjunctivitis, with no specific antiviral therapy available. An adenoviral vaccine based on human adenovirus species D (HAdV-D) is currently in use for COVID-19. Herein, we investigate host interactions of HAdV-D type 37 (HAdV-D37) protein IIIa (pIIIa), identified by affinity purification and mass spectrometry (AP-MS) screens. We demonstrate that viral pIIIa interacts with ubiquitin-specific protease 9x (USP9x) and Ran-binding protein 2 (RANBP2). USP9x binding did not invoke its signature deubiquitination function but rather deregulated pIIIa-RANBP2 interactions. In USP9x-knockout cells, viral genome replication and viral protein expression increased compared to wild type cells, supporting a host-favored mechanism for USP9x. Conversely, RANBP2-knock down reduced pIIIa transport to the nucleus, viral genome replication, and viral protein expression. Also, RANBP2-siRNA pretreated cells appeared to contain fewer mature viral particles. Transmission electron microscopy of USP9x-siRNA pretreated, virus-infected cells revealed larger than typical paracrystalline viral arrays. RANBP2-siRNA pretreatment led to the accumulation of defective assembly products at an early maturation stage. CRM1 nuclear export blockade by leptomycin B led to the retention of pIIIa within cell nuclei and hindered pIIIa-RANBP2 interactions. In-vitro binding analyses indicated that USP9x and RANBP2 bind to C-terminus of pIIIa amino acids 386-563 and 386-510, respectively. Surface plasmon resonance testing showed direct pIIIa interaction with recombinant USP9x and RANBP2 proteins, without competition. Using an alternative and genetically disparate adenovirus type (HAdV-C5), we show that the demonstrated pIIIa interaction is also important for a severe respiratory pathogen. Together, our results suggest that pIIIa hijacks RANBP2 for nuclear import and subsequent virion assembly. USP9x counteracts this interaction and negatively regulates virion synthesis. This analysis extends the scope of known adenovirus-host interactions and has potential implications in designing new antiviral therapeutics.
Zabaleta N, Bhatt U, Hérate C, Maisonnasse P, Sanmiguel J, Diop C, Castore S, Estelien R, Li D, Dereuddre-Bosquet N, Cavarelli M, Gallouët A-S, Pascal Q, Naninck T, Kahlaoui N, Lemaitre J, Relouzat F, Ronzitti G, Thibaut HJ, Montomoli E, Wilson JM, Le Grand R, Vandenberghe LH. Durable immunogenicity, adaptation to emerging variants, and low-dose efficacy of an AAV-based COVID-19 vaccine platform in macaques. Mol Ther 2022;30(9):2952-2967.Abstract
The COVID-19 pandemic continues to have devastating consequences on health and economy, even after the approval of safe and effective vaccines. Waning immunity, the emergence of variants of concern, breakthrough infections, and lack of global vaccine access and acceptance perpetuate the epidemic. Here, we demonstrate that a single injection of an adenoassociated virus (AAV)-based COVID-19 vaccine elicits at least 17-month-long neutralizing antibody responses in non-human primates at levels that were previously shown to protect from viral challenge. To improve the scalability of this durable vaccine candidate, we further optimized the vector design for greater potency at a reduced dose in mice and non-human primates. Finally, we show that the platform can be rapidly adapted to other variants of concern to robustly maintain immunogenicity and protect from challenge. In summary, we demonstrate this class of AAV can provide durable immunogenicity, provide protection at dose that is low and scalable, and be adapted readily to novel emerging vaccine antigens thus may provide a potent tool in the ongoing fight against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2).
Maciorowski D, Diop C, Bhatt U, Estelien R, Li D, Chauhan R, Vandenberghe LH, Zabaleta N. Immunogenicity of an AAV-Based COVID-19 Vaccine in Murine Models of Obesity and Aging. Viruses 2022;14(4)Abstract
The SARS-CoV-2 pandemic has had a disastrous impact on global health. Although some vaccine candidates have been effective in combating SARS-CoV-2, logistical, economical, and sociological aspects still limit vaccine access globally. Recently, we reported on two room-temperature stable AAV-based COVID-19 vaccines that induced potent and protective immunogenicity following a single injection in murine and primate models. Obesity and old age are associated with increased mortality in COVID-19, as well as reduced immunogenicity and efficacy of vaccines. Here, we investigated the effectiveness of the AAVCOVID vaccine candidates in murine models of obesity and aging. Results demonstrate that obesity did not significantly alter the immunogenicity of either vaccine candidate. In aged mice, vaccine immunogenicity was impaired. These results suggest that AAV-based vaccines may have limitations in older populations and may be equally applicable in obese and non-obese populations.
Ou J, Lan W, Wu X, Zhao T, Duan B, Yang P, Ren Y, Quan L, Zhao W, Seto D, Chodosh J, Luo Z, Wu J, Zhang Q. Tracking SARS-CoV-2 Omicron diverse spike gene mutations identifies multiple inter-variant recombination events. Signal Transduct Target Ther 2022;7(1):138.Abstract
The current pandemic of COVID-19 is fueled by more infectious emergent Omicron variants. Ongoing concerns of emergent variants include possible recombinants, as genome recombination is an important evolutionary mechanism for the emergence and re-emergence of human viral pathogens. In this study, we identified diverse recombination events between two Omicron major subvariants (BA.1 and BA.2) and other variants of concern (VOCs) and variants of interest (VOIs), suggesting that co-infection and subsequent genome recombination play important roles in the ongoing evolution of SARS-CoV-2. Through scanning high-quality completed Omicron spike gene sequences, 18 core mutations of BA.1 (frequency >99%) and 27 core mutations of BA.2 (nine more than BA.1) were identified, of which 15 are specific to Omicron. BA.1 subvariants share nine common amino acid mutations (three more than BA.2) in the spike protein with most VOCs, suggesting a possible recombination origin of Omicron from these VOCs. There are three more Alpha-related mutations in BA.1 than BA.2, and BA.1 is phylogenetically closer to Alpha than other variants. Revertant mutations are found in some dominant mutations (frequency >95%) in the BA.1. Most notably, multiple characteristic amino acid mutations in the Delta spike protein have been also identified in the "Deltacron"-like Omicron Variants isolated since November 11, 2021 in South Africa, which implies the recombination events occurring between the Omicron and Delta variants. Monitoring the evolving SARS-CoV-2 genomes especially for recombination is critically important for recognition of abrupt changes to viral attributes including its epitopes which may call for vaccine modifications.
Xiong X, Tian S, Yang P, Lebreton F, Bao H, Sheng K, Yin L, Chen P, Zhang J, Qi W, Ruan J, Wu H, Chen H, Breault DT, Wu H, Earl AM, Gilmore MS, Abraham J, Dong M. Emerging enterococcus pore-forming toxins with MHC/HLA-I as receptors. Cell 2022;Abstract
Enterococci are a part of human microbiota and a leading cause of multidrug resistant infections. Here, we identify a family of Enterococcus pore-forming toxins (Epxs) in E. faecalis, E. faecium, and E. hirae strains isolated across the globe. Structural studies reveal that Epxs form a branch of β-barrel pore-forming toxins with a β-barrel protrusion (designated the top domain) sitting atop the cap domain. Through a genome-wide CRISPR-Cas9 screen, we identify human leukocyte antigen class I (HLA-I) complex as a receptor for two members (Epx2 and Epx3), which preferentially recognize human HLA-I and homologous MHC-I of equine, bovine, and porcine, but not murine, origin. Interferon exposure, which stimulates MHC-I expression, sensitizes human cells and intestinal organoids to Epx2 and Epx3 toxicity. Co-culture with Epx2-harboring E. faecium damages human peripheral blood mononuclear cells and intestinal organoids, and this toxicity is neutralized by an Epx2 antibody, demonstrating the toxin-mediated virulence of Epx-carrying Enterococcus.
Ashkenazy N, Patel NA, Sridhar J, Yannuzzi NA, Belin PJ, Kaplan R, Kothari N, Benitez Bajandas GA, Kohly RP, Roizenblatt R, Pinhas A, Mundae R, Rosen RB, Ryan EH, Chiang A, Chang LK, Khurana RN, Finn AP. Hemi- and Central Retinal Vein Occlusion Associated with COVID-19 Infection in Young Patients without Known Risk Factors. Ophthalmol Retina 2022;6(6):520-530.Abstract
PURPOSE: Venous thromboembolic complications have been reported in association with coronavirus disease 2019 (COVID-19) infection. We raised awareness regarding a potential temporal association between COVID-19 infection and retinal vein occlusion (RVO). DESIGN: Multicenter, retrospective, nonconsecutive case series. SUBJECTS: Patients presenting with hemi-RVO (HRVO) or central RVO (CRVO) between March 2020 and March 2021, with confirmed COVID-19 infection, were included. The exclusion criteria were as follows: age >50 years, hypertension, diabetes, glaucoma, obesity, underlying hypercoagulable states, and those requiring intubation during hospitalization. METHODS: This was a multicenter, retrospective, nonconsecutive case series including patients presenting with hemi-RVO (HRVO) or central RVO (CRVO) between March 2020 and March 2021, with confirmed COVID-19 infection. The exclusion criteria were as follows: age >50 years, hypertension, diabetes, glaucoma, obesity, underlying hypercoagulable states, and those requiring intubation during hospitalization. MAIN OUTCOME MEASURES: Ophthalmic findings, including presenting and final visual acuity (VA), imaging findings, and clinical course. RESULTS: Twelve eyes of 12 patients with CRVO (9 of 12) or HRVO (3 of 12) after COVID-19 infection were included. The median age was 32 years (range, 18-50 years). Three patients were hospitalized, but none were intubated. The median time from COVID-19 diagnosis to ophthalmic symptoms was 6.9 weeks. The presenting VA ranged from 20/20 to counting fingers, with over half (7 of 12) having a VA of ≥20/40. OCT revealed macular edema in 42% of the eyes; of these, 80% (4 of 5) were treated with anti-VEGF injections. Ninety-two percent (11 of 12) had partial or complete resolution of ocular findings at final follow-up. Four eyes (33%) had retinal thinning, as determined using OCT, by the end of the study interval. The final VA ranged from 20/20 to 20/60, with 11 of the 12 (92%) eyes achieving a VA of ≥20/40 at a median final follow-up period of 13 weeks (range, 4-52 weeks). CONCLUSIONS: Although we acknowledge the high seroprevalence of COVID-19 and that a causal relationship cannot be established, we reported this series to raise awareness regarding the potential risk of retinal vascular events due to a heightened thromboinflammatory state associated with COVID-19 infection.
Deiner MS, Seitzman GD, Kaur G, McLeod SD, Chodosh J, Lietman TM, Porco TC. Sustained Reductions in Online Search Interest for Communicable Eye and Other Conditions During the COVID-19 Pandemic: Infodemiology Study. JMIR Infodemiology 2022;2(1):e31732.Abstract
Background: In a prior study at the start of the pandemic, we reported reduced numbers of Google searches for the term "conjunctivitis" in the United States in March and April 2020 compared with prior years. As one explanation, we conjectured that reduced information-seeking may have resulted from social distancing reducing contagious conjunctivitis cases. Here, after 1 year of continued implementation of social distancing, we asked if there have been persistent reductions in searches for "conjunctivitis," and similarly for other communicable disease terms, compared to control terms. Objective: The aim of this study was to determine if reduction in searches in the United States for terms related to conjunctivitis and other common communicable diseases occurred in the spring-winter season of the COVID-19 pandemic, and to compare this outcome to searches for terms representing noncommunicable conditions, COVID-19, and to seasonality. Methods: Weekly relative search frequency volume data from Google Trends for 68 search terms in English for the United States were obtained for the weeks of March 2011 through February 2021. Terms were classified a priori as 16 terms related to COVID-19, 29 terms representing communicable conditions, and 23 terms representing control noncommunicable conditions. To reduce bias, all analyses were performed while masked to term names, classifications, and locations. To test for the significance of changes during the pandemic, we detrended and compared postpandemic values to those expected based on prepandemic trends, per season, computing one- and two-sided P values. We then compared these P values between term groups using Wilcoxon rank-sum and Fisher exact tests to assess if non-COVID-19 terms representing communicable diseases were more likely to show significant reductions in searches in 2020-2021 than terms not representing such diseases. We also assessed any relationship between a term's seasonality and a reduced search trend for the term in 2020-2021 seasons. P values were subjected to false discovery rate correction prior to reporting. Data were then unmasked. Results: Terms representing conjunctivitis and other communicable conditions showed a sustained reduced search trend in the first 4 seasons of the 2020-2021 COVID-19 pandemic compared to prior years. In comparison, the search for noncommunicable condition terms was significantly less reduced (Wilcoxon and Fisher exact tests, P<.001; summer, autumn, winter). A significant correlation was also found between reduced search for a term in 2020-2021 and seasonality of that term (Theil-Sen, P<.001; summer, autumn, winter). Searches for COVID-19-related conditions were significantly elevated compared to those in prior years, and searches for influenza-related terms were significantly lower than those for prior years in winter 2020-2021 (P<.001). Conclusions: We demonstrate the low-cost and unbiased use of online search data to study how a wide range of conditions may be affected by large-scale interventions or events such as social distancing during the COVID-19 pandemic. Our findings support emerging clinical evidence implicating social distancing and the COVID-19 pandemic in the reduction of communicable disease and on ocular conditions.
Reshef ER, Freitag SK, Lee NG. Orbital Inflammation Following COVID-19 Vaccination. Ophthalmic Plast Reconstr Surg 2022;38(3):e67-e70.Abstract
Three patients presented with periorbital swelling, pain with extraocular movements, and binocular diplopia 1-4 days after receiving an mRNA Coronavirus Infectious Disease-19 (COVID-19) vaccine (BNT162b2, Pfizer/BioNTech; mRNA-1273, Moderna). All patients had a normal afferent function, unilateral limitation of extraocular motility, proptosis, and periorbital inflammation. Neuroimaging of the orbits with contrast revealed inflammation and enlargement of extraocular muscles in 2 cases and the lacrimal gland in 1 case. In all 3 cases, an extensive infectious and inflammatory laboratory work-up was unremarkable and signs and symptoms of orbital inflammation rapidly improved to complete resolution after treatment with high-dose oral prednisone. This is the first reported series of orbital inflammation occurring shortly after administration of the COVID-19 vaccine. Clinicians may consider an inflammatory postvaccine etiology as an alternative to presumed idiopathic diagnosis in such cases.
Andre C, Rouhana J, de Mello SS, da Cunha GR, Van Camp AG, Gilmore MS, Bispo PJM. Population structure of ocular Streptococcus pneumoniae is highly diverse and formed by lineages that escape current vaccines. Microb Genom 2022;8(3)Abstract
Streptococcus pneumoniae is a leading cause of ocular infections including serious and sight-threatening conditions. The use of pneumococcal conjugate vaccines (PCV) has substantially reduced the incidence of pneumonia and invasive pneumococcal diseases, but has had limited impact on ocular infections. Additionally, widespread vaccine use has resulted in ongoing selective pressure and serotype replacement in carriage and disease. To gain insight into the population structure of pneumococcal isolates causing ocular infections in a post-PCV-13 time period, we investigated the genomic epidemiology of ocular S. pneumoniae isolates (n=45) collected at Massachusetts Eye and Ear between 2014 and 2017. By performing a series of molecular typing methods from draft genomes, we found that the population structure of ocular S. pneumoniae is highly diverse with 27 sequence types (grouped into 18 clonal complexes) and 17 serotypes being identified. Distribution of these lineages diverged according to the site of isolation, with conjunctivitis being commonly caused by isolates grouped in the Epidemic Conjunctivitis Cluster-ECC (60 %), and ST448 (53.3 %) being most frequently identified. Conversely, S. pneumoniae keratitis cases were caused by a highly diverse population of isolates grouping within 15 different clonal complexes. Serotyping inference demonstrated that 95.5 % of the isolates were non-PCV-13 vaccine types. Most of the conjunctivitis isolates (80 %) were unencapsulated, with the remaining belonging to serotypes 15B, 3 and 23B. On the other hand, S. pneumoniae causing keratitis were predominantly encapsulated (95.2 %) with 13 different serotypes identified, mostly being non-vaccine types. Carriage of macrolide resistance genes was common in our ocular S. pneumoniae population (42.2 %), and usually associated with the mefA +msrD genotype (n=15). These genes were located in the Macrolide Efflux Genetic Assembly cassette and were associated with low-level in vitro resistance to 14- and 15-membered macrolides. Less frequently, macrolide-resistant isolates carried an ermB gene (n=4), which was co-located with the tetM gene in a Tn-916-like transposon. Our study demonstrates that the population structure of ocular S. pneumoniae is highly diverse, mainly composed by isolates that escape the PCV-13 vaccine, with patterns of tissue/niche segregation, adaptation and specialization. These findings suggest that the population structure of ocular pneumococcus may be shaped by multiple factors including PCV-13 selective pressure, microbial-related and niche-specific host-associated features.
Naninck T, Kahlaoui N, Lemaitre J, Maisonnasse P, De Mori A, Pascal Q, Contreras V, Marlin R, Relouzat F, Delache B, Hérate C, Aldon Y, van Gils M, Zabaleta N, Tsong Fang RH, Bosquet N, Sanders RW, Vandenberghe LH, Chapon C, Le Grand R. Computed tomography and [18F]-FDG PET imaging provide additional readouts for COVID-19 pathogenesis and therapies evaluation in non-human primates. iScience 2022;25(4):104101.Abstract
Non-human primates (NHPs) are particularly relevant as preclinical models for SARS-CoV-2 infection and nuclear imaging may represent a valuable tool for monitoring infection in this species. We investigated the benefit of computed X-ray tomography (CT) and [18F]-FDG positron emission tomography (PET) to monitor the early phase of the disease in a large cohort (n = 76) of SARS-CoV-2 infected macaques. Following infection, animals showed mild COVID-19 symptoms including typical lung lesions. CT scores at the acute phase reflect the heterogeneity of lung burden following infection. Moreover, [18F]-FDG PET revealed that FDG uptake was significantly higher in the lungs, nasal cavities, lung-draining lymph nodes, and spleen of NHPs by 5 days postinfection compared to pre-infection levels, indicating early local inflammation. The comparison of CT and PET data from previous COVID-19 treatments or vaccines we tested in NHP, to this large cohort of untreated animals demonstrated the value of in vivo imaging in preclinical trials.
Bispo PJM, Sahm DF, Asbell PA. A Systematic Review of Multi-decade Antibiotic Resistance Data for Ocular Bacterial Pathogens in the United States. Ophthalmol Ther 2022;11(2):503-520.Abstract
INTRODUCTION: Since 2009, the Antibiotic Resistance Monitoring in Ocular Microorganisms (ARMOR) surveillance study has been assessing in vitro antibiotic resistance for bacterial isolates sourced from ocular infections in the US. The main goal of this systematic review was to compare in vitro resistance data for ocular pathogens from published US studies with the most recently published data from the ARMOR study (2009-2018) and, where possible, to evaluate trends in bacterial resistance over time over all studies. METHODS: A literature search was conducted using MEDLINE®, BIOSIS Previews®, and EMBASE® databases (1/1/1995-6/30/2021). Data were extracted from relevant studies and antibiotic susceptibility rates for common ocular pathogens (Staphylococcus aureus, coagulase-negative staphylococci [CoNS], Streptococcus pneumoniae, Pseudomonas aeruginosa, and Haemophilus influenzae), longitudinal changes in susceptibility, and multidrug resistance (MDR) were compared descriptively. RESULTS: Thirty-two relevant studies were identified. High in vitro resistance was found among S. aureus and CoNS to fluoroquinolones, macrolides, and methicillin/oxacillin across studies, with high rates of MDR noted, specifically among methicillin-resistant staphylococci. Data from studies pre-dating or overlapping the early years of ARMOR reflected increasing rates of S. aureus resistance to fluoroquinolones, macrolides, methicillin/oxacillin, and aminoglycosides, while the ARMOR data suggested slight decreases in resistance to these classes between 2009 and 2018. Overall, methicillin-resistant S. aureus (MRSA) prevalence peaked from 2005 to 2015 with a possible decreasing trend in more recent years. DISCUSSION AND CONCLUSIONS: Data from local and regional US datasets were generally consistent with data from the national ARMOR surveillance study. Continued surveillance of ocular bacterial pathogens is needed to track trends such as methicillin resistance and MDR prevalence and any new emerging antibiotic resistance phenotypes. Susceptibility data from ARMOR can inform initial choice of therapy, especially in practice areas where local antibiograms are unavailable.