Epidemiological Characteristics of Carbapenem-Resistant Enterobacterales in Japan: A Nationwide Analysis of Data from a Clinical Laboratory Center (2016-2022).

In Japan, nationwide epidemiological surveys on carbapenem-resistant Enterobacterales (CREs), including comprehensive information, are scarce, with most data available only through public reports. This study analyzed data on the Enterobacterales family collected from nationwide testing centers between January 2016 and December 2022, focusing on isolates that met the criteria for CRE in Japan based on drug susceptibility. We investigated 5,323,875 Enterobacterales isolates of 12 different species; among 4696 (0.09%) CRE strains, the proportion of major CRE isolates was as follows: Escherichia coli, 31.3%; Klebsiella pneumoniae, 28.0%; Enterobacter cloacae, 18.5%; and Klebsiella aerogenes, 6.7%. Moreover, over a 7-year period, Providencia rettgeri, E. cloacae, K. aerogenes, and K. pneumoniae demonstrated relatively high CRE percentages of 0.6% (156/26,185), 0.47% (869/184,221), 0.28% (313/110,371), and 0.17% (1314/780,958), respectively. The number of CRE strains isolated from different samples was as follows: urine, 2390; respiratory specimens, 1254; stool, 425; blood, 252; others, 375. In the broader context, including colonization, the predominant isolates of CREs collected at nationwide testing centers are E. coli and K. pneumoniae. Furthermore, recently, attention has been directed toward less common CRE species, such as Klebsiella oxytoca and Providencia rettgeri, and thus, it might be necessary to continue monitoring these less common species.

Screening for Metallo-Beta-Lactamases Using Non-Carbapenem Agents: Effective Detection of MBL-Producing Enterobacterales and Differentiation of Carbapenem-Resistant Enterobacterales.

Metallo-beta-lactamases (MBLs) are enzymes that break down carbapenem antibiotics, leading to carbapenem-resistant organisms. Carbapenemase-resistant Enterobacterales (CRE) is one of them. Outbreaks of CRE infection can occur in healthcare facilities and lead to increased deaths, illness, and medical costs. This study was conducted to detect MBLs using non-carbapenem agents and exclude MBLs among CRE isolates. A total of 3776 non-duplicate sequential Enterobacterales isolates from a single facility were screened between January 2019 and December 2022 using non-carbapenem agents, ceftazidime and cefoperazone/sulbactam. Positive 153 isolates (4.0%) were further tested using carbapenemase-confirmation tests and verified through polymerase chain reaction (PCR) testing. Fifteen imipenemase (IMP)-type MBL-producing Enterobacterales (0.4%) including one susceptible to carbapenems were identified. Moreover, 160 isolates (4.2%) meeting the criteria for CRE were directly subjected to PCR testing. All fourteen CRE isolates with MBLs identified through PCR testing were found to be the same strains screened using ceftazidime and cefoperazone/sulbactam. Screening using ceftazidime and cefoperazone/sulbactam can effectively detect MBL-producing Enterobacterales strains. This screening method showed comparable results to screening with meropenem, potentially serving as a supplementary approach and contributing to differentiating between MBL- and non-MBL-producing CRE strains. Our findings support these screening methods, particularly in regions where IMP-type MBLs are prevalent.

Circulating Extracellular Vesicle Levels in Patients with Coronavirus Disease 2019 Coagulopathy: A Prospective Cohort Study.

Coronavirus disease 2019 (COVID-19) is associated with coagulopathy. However, the underlying mechanisms are not completely understood. We evaluated the association between COVID-19 coagulopathy and extracellular vesicle (EV) levels. We hypothesized that several EV levels would be higher in COVID-19 coagulopathy patients than in non-coagulopathy patients. This prospective observational study was conducted in four tertiary care faculties in Japan. We enrolled 99 COVID-19 patients (48 with coagulopathy and 51 without coagulopathy) aged ≥20 years who required hospitalization, and 10 healthy volunteers; we divided the patients into coagulopathy and non-coagulopathy groups according to the D-dimer levels (≥1 µg/mL and <1 µg/mL, respectively). We used flow cytometry to measure the tissue-factor-bearing, endothelium-derived, platelet-derived, monocyte-derived, and neutrophil-derived EV levels in platelet-free plasma. The EV levels were compared between the two COVID-19 groups as well as among the coagulopathy patients, non-coagulopathy patients, and healthy volunteers. No significant difference was found in EV levels between the two groups. Meanwhile, the cluster of differentiation (CD) 41 + EV levels were significantly higher in COVID-19 coagulopathy patients than in healthy volunteers (549.90 [255.05-984.65] vs. 184.3 [150.1-254.1] counts/µL, p = 0.011). Therefore, CD41+ EVs might play an essential role in COVID-19 coagulopathy development.

Clinical and Epidemiological Characteristics of Persistent Bacteremia: A Decadal Observational Study.

Background: Bloodstream infections (BSIs), including persistent bacteremia (PB), are a leading source of morbidity and mortality globally. PB has a higher mortality rate than non- PB, but the clinical aspects of PB in terms of the causative pathogens and the presence of clearance of PB are not well elucidated. Therefore, this study aimed to describe the clinical and epidemiological characteristics of PB in a real-world clinical setting. Methods: We performed a retrospective observational survey of patients who underwent blood culture between January 2012 and December 2021 at Tohoku University Hospital. Cases of PB were divided into three groups depending on the causative pathogen: gram-positive cocci (GPC), gram-negative rods (GNRs), and Candida spp. For each group, we examined the clinical and epidemiological characteristics of PB, including differences in clinical features depending on the clearance of PB. The main outcome variable was mortality, assessed as early (30-day), late (30-90 day), and 90-day mortality. Results: Overall, we identified 31,591 cases of single bacteremia; in 6709 (21.2%) cases, the first blood culture was positive, and in 3124 (46.6%) cases, a follow-up blood culture (FUBC) was performed. Of the cases with FUBCs, 414 (13.2%) were confirmed to be PB. The proportion of PB cases caused by Candida spp. was significantly higher (29.6%, 67/226 episodes) than that for GPC (11.1%, 220/1974 episodes, p < 0.001) and GNRs (12.1%, 100/824 episodes, p < 0.001). The Candida spp. group also had the highest late (30-90 day) and 90-day mortality rates. In all three pathogen groups, the subgroup without the clearance of PB tended to have a higher mortality rate than the subgroup with clearance. Conclusions: Patients with PB due to Candida spp. have a higher late (30-90 day) and 90-day mortality rate than patients with PB due to GPC or GNRs. In patients with PB, FUBCs and confirming the clearance of PB are useful to improve the survival rate.

Severe coronavirus disease 2019 in a patient with TAFRO syndrome: A case report.

Background: TAFRO syndrome, a subtype of idiopathic multicentric Castleman disease, is an acute or subacute systemic inflammatory disease that causes fever, generalized oedema (pleural effusion or ascites), and thrombocytopenia and is associated with renal impairment, anaemia, and organomegaly (hepatosplenomegaly and lymph node enlargement). Coronavirus disease 2019 (COVID-19)-associated hyperinflammation is caused by dysregulation of proinflammatory cytokines. Cytokine storm syndrome is common to both COVID-19 and TAFRO syndrome.Case report.A 66-year-old man with TAFRO syndrome was admitted because of worsening renal function, right pleural effusion, and ascites. He was taking 20 mg prednisolone orally and 25 mg cyclosporin A orally twice daily. Despite administration of maximum oxygenation and remdesivir, the patient developed acute respiratory distress syndrome (ARDS) and was transferred to the intensive care unit. Results: Chest radiography showed bilateral lung infiltration. COVID-19 was confirmed with a positive polymerase chain reaction test for severe acute respiratory syndrome coronavirus 2. Chest and abdominal computed tomography showed massive ground-glass opacities in both lungs, slight right pleural effusion, hepatomegaly, splenomegaly, and ascites. Conclusion: To the best of our knowledge, this is the first report of COVID-19 in a patient with TAFRO syndrome. Despite receiving a moderate dose of a corticosteroid and a monoclonal antibody against the IL-6 receptor, our patient developed severe pneumonia, suggesting that strong immunomodulatory therapy in the antiviral phase of COVID-19 may promote viral growth and induce ARDS.

Case Report: Successful Treatment of Five Critically Ill Coronavirus Disease 2019 Patients Using Combination Therapy With Etoposide and Corticosteroids.

Acute respiratory distress syndrome (ARDS) is the leading cause of mortality in hospitalized patients with coronavirus disease 2019 (COVID-19) because of limited effective therapies. During infection, the accumulation and activation of macrophages and monocytes in the lungs induce inflammatory mediators and contribute to tissue injury, leading to ARDS. However, therapeutic strategies that directly target activated macrophage and monocytes have not been reported. Combination treatment with etoposide (a cytotoxic agent) and a corticosteroid has been widely used for treating hemophagocytic lymphohistiocytosis characterized by the systemic activation of macrophages with overwhelming inflammation. Herein, we present five cases of COVID-19-associated ARDS treated with etoposide and corticosteroids. Three of the five patients were over 65 years of age and had various underlying diseases, including multiple myeloma. Four patients required invasive mechanical ventilation (MV), and one patient refused to be placed on MV due to underlying diseases. All patients were pre-treated with antiviral and/or other anti-inflammatory agents, but their condition deteriorated and hyperinflammation was noted. All five patients responded well to treatment and had an immediate response, as reflected by improvement in their respiratory condition and inflammatory marker levels and rapid resolution of fever after etoposide administration; however, some patients required a second dose of etoposide and longer course of steroids. All patients recovered, and there were no severe adverse events related to the drugs. Following successful treatment in these five patients, we plan to conduct a clinical trial to evaluate the efficacy and safety of combination therapy with etoposide and corticosteroid for treating COVID-19 patients in Japan.

Marchiafava-Bignami disease with haemophagocytic lymphohistiocytosis as a postoperative complication of cardiac surgery.

Marchiafava-Bignami disease (MBD) is a rare complication of chronic alcoholism; however, MBD in a non-alcoholic diabetic patient has rarely been reported. The aetiology or pathophysiology of MBD is still unknown. A 50-year-old man with a history of untreated diabetes mellitus underwent on-pump beating coronary artery bypass graft surgery (CABG) surgery for three-vessel and left main coronary disease. 3 days after the surgery, he developed a fever over 40°C and entered a coma state. MRI revealed multiple lesions, including in the corpus callosum, globus pallidus, brain stem and upper cervical spinal cord, which suggested MBD. The patient did not respond to thiamine therapy, but partly responded to steroid therapy. He ultimately died of respiratory failure. The autopsy revealed MBD and haemophagocytic lymphohistiocytosis. It is rare, but systemic inflammatory response syndrome induced by on-pump beating CABG could develop these complication.

Fingolimod-associated PML with mild IRIS in MS: A clinicopathologic study.

OBJECTIVE: To clarify the clinical, neuropathologic, and virologic characteristics of progressive multifocal leukoencephalopathy (PML) and its immune reconstitution inflammatory syndrome (IRIS) in a patient with fingolimod-treated MS. METHODS: A case study. RESULTS: A 34-year-old patient with MS using fingolimod for 4 years had a gradual progression of right hemiparesis and aphasia with a new subcortical white matter lesion in the precentral gyrus by initial MRI. Blood tests were normal, except for lymphopenia (160 cells/µL). One month after the cessation of fingolimod, brain MRI depicted a diffusely exacerbated hyperintensity on fluid-attenuated inversion recovery and diffusion-weighed imaging in the white matter with punctate gadolinium enhancement, suggesting PML-IRIS. A very low level of JC virus (JCV)-DNA (15 copies/mL) was detected in the CSF as judged by quantitative PCR. Brain tissues were biopsied from the left frontal lesion, which showed some small demyelinated foci with predominant loss of myelin-associated glycoprotein with infiltrations of lymphocytes and macrophages, but clear viral inclusion was not observed with hematoxylin-eosin staining. JCV-DNA was uniquely detectable in an active inflammatory demyelinating lesion by in situ hybridization, possibly suggesting an early phase of PML. DNA extracted from the brain sample was positive for JCV-DNA (151 copies/cell). It took 3 months to normalize the blood lymphocyte count. The patient was treated with 1 g of IV methylprednisolone for 3 days and a weekly oral dose (375 mg) of mefloquine, and her symptoms gradually improved. CONCLUSION: Low CSF JCV-DNA and unfound viral inclusions initially made her diagnosis difficult. The clinical course of fingolimod-associated PML may be associated with mild immune reconstitution.

An Acute Case of Granulomatous Amoebic Encephalitis-Balamuthia mandrillaris Infection.

A 74-year-old woman who exhibited drowsiness was referred to our hospital. Enhanced head magnetic resonance imaging (MRI) revealed multiple ring-enhancing lesions and lesions showing partial mild hemorrhaging. The patient gradually progressed to a comatose condition with notable brain deterioration of unknown cause on follow-up MRI. On day nine, the patient inexplicably died, although brain herniation was suspected. Autopsy and histopathology revealed numerous amoebic trophozoites in the perivascular spaces and within the necrotic tissue. Brain immunostaining tested positive for Balamuthia mandrillaris. Infection due to free-living amoeba is rare in Japan; however, it may increase in the near future due to unknown reasons.

Longitudinally extensive transverse myelitis with anti-NMDA receptor antibodies during a systemic lupus erythematosus flare-up.

Transverse myelitis (TM) with systemic lupus erythematosus (SLE) has been linked to the presence of autoantibodies (eg, antiaquaporin 4 (AQP4) and anticardiolipin (aCL)) and SLE-induced secondary vasculitis, but the aetiology remains incompletely understood. A 48-year-old Japanese man with a 6-year history of poorly controlled SLE had stopped glucocorticoid therapy 1 year before admission. 3 days before admission, he developed flaccid paraplegia. Spinal MRI showed a longitudinally hyperintense T2 grey matter lesion from the level of Th4 to the conus medullaris, which was considered longitudinally extensive TM (LETM). We administered steroid pulse therapy (methyl-prednisolone 1000 mg/day) for 3 days and prednisolone 50 mg/day. The patient's flaccid paralysis gradually improved. We concluded that the patient's TM was caused by SLE flare-up, even though we could not completely rule out antiphospholipid syndrome. SLE myelitis is relatively rare and many aetiologies are possible for TM in SLE.