COVID-19 severity and corticosteroid treatment have minimal effect on specific antibody production.

BACKGROUND: Dexamethasone is currently administered for Coronavirus disease 2019(COVID-19); however, there are concerns about its effect on specific antibodies' production. The aim of this study was to evaluate whether specific antibodies were affected by COVID-19 severity and corticosteroid treatment. METHODS: Of 251 confirmed COVID-19 patients admitted to our hospital between January 26 and August 10, 2020, the early period of the pandemic, 75 patients with sera within 1 month of onset and 1 month or longer were included in the research. A total of 253 serum samples from these patients were collected. The levels of specific antibodies for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2), immunoglobulin G (IgG) and M (IgM), were measured retrospectively. The results were compared separately of each COVID-19 severity, and with or without corticosteroid treatment. RESULTS: Among the 75 patients, 47, 18, and 10 had mild, moderate, and severe disease, respectively. The median age was 53.0 years and 22 (29%) were women. The most common comorbidities were hypertension and dyslipidemia. Corticosteroids were administered to 20 (27%) and 10 (53%), patients with moderate and severe disease, respectively. The positivity rates IgM increased first, and IgG was almost always positive after day 16, regardless of the severity of COVID-19. On days 6-10, both IgG and IgM positivity rates were higher in patients with moderate disease than in those with mild or severe disease. In patients with moderate disease, IgG positivity was similar over time, regardless of corticosteroid treatment. CONCLUSIONS: In COVID-19 patients, specific IgG is positive and maintained for a long period of time, even after corticosteroid treatment. The effect of corticosteroid treatment in a COVID-19 epidemiological study using specific IgG antibodies was considered minor. COVID-19 patients were more likely to receive oxygen if IgM was positive 1 week after onset, but not mechanical ventilation. IgM measurement 1 week after onset may predict COVID-19 severity.

Efficacy and viral dynamics of tecovirimat in patients with MPOX: A multicenter open-label, double-arm trial in Japan.

INTRODUCTION: Tecovirimat's application in treating mpox remains under-researched, leaving gaps in clinical and virological understanding. METHODS: The Tecopox study in Japan evaluated the efficacy and safety of tecovirimat in patients with smallpox or mpox, who were divided into oral tecovirimat and control groups. Patients with mpox enrolled between June 28, 2022, and April 30, 2023, were included. Demographic and clinical details along with blood, urine, pharyngeal swab, and skin lesion samples were gathered for viral analysis. A multivariable Tobit regression model was employed to identify factors influencing prolonged viral detection. RESULTS: Nineteen patients were allocated to the tecovirimat group, and no patients were allocated to the control group. The median age was 38.5 years, and all patients were males. Ten patients (52.6%) were infected with human immunodeficiency virus (HIV). Sixteen patients (84.2%) had severe disease. Nine of the 15 patients (60.0%) (four patients withdrew before day 14) had negative PCR results for skin lesion specimens 14 days after inclusion. The mortality rates were 0% on days 14 and 30. No severe adverse events were reported. HIV status and the number of days from symptom onset to tecovirimat administration were associated with lower Ct values (p = 0.027 and p < 0.001, respectively). The median number of days when PCR testing did not detect the mpox virus in each patient was 19.5 days. CONCLUSION: Early tecovirimat administration might reduce viral shedding duration, thereby mitigating infection spread. Moreover, patients infected with HIV showed prolonged viral shedding, increasing the transmission risk compared to those without HIV.

Aortic endograft infection by Mycobacterium abscessus subsp. massiliense with acquired clarithromycin resistance: a case report.

BACKGROUND: Mycobacterium abscessus subsp. massiliense (MMA) comprises a group of non-tuberculous, rapidly growing mycobacteria. Although MMA can cause pulmonary diseases, surgical site infections, and disseminated diseases, aortic endograft infection has not been reported. Here, we describe the first case of aortic endograft infection caused by MMA. CASE PRESENTATION: Two months after stent-graft insertion for an abdominal aortic aneurysm, an 85-year-old man was admitted with fever and abdominal pain and was diagnosed with aortic endograft infection. Despite 14 days of meropenem and vancomycin intravenous administration, periaortic fluid pooling increased as compared to that before antibiotic administration. The abscess was drained, and fluorescent acid-fast staining of the abscess fluid revealed bacilli. We conducted genetic tests on the genes hsp65, rpoB, and sodA, performed Whole Genome Sequencing (WGS), and identified the organism as MMA. Intravenous imipenem-cilastatin (IPM/CS), amikacin (AMK), and oral clarithromycin (CAM) were administered. After 2 months, oral CAM and sitafloxacin were administered because the abscess had decreased in size. However, after 6 weeks, the abscess increased in size again. Antimicrobial susceptibility testing of the drainage fluid from the abscess resulted in the isolation of an MMA strain that had acquired resistance to CAM. Intravenous IPM/CS, AMK, and oral linezolid were added to the treatment regimen along with oral CAM and STFX. However, he was not fully cured and died 6 months later. Neither the full-length erythromycin ribosome methyltransferase (erm)(41) gene nor the rrl or rpIV gene mutations were found by Sanger sequencing in the pre- and post-treatment strains. Whole-genome sequence analysis of the post-treatment strain revealed mutations in genes with no previous reports of association with macrolide resistance. CONCLUSIONS: Aortic endograft infection caused by MMA strain is extremely rare; nonetheless, MMA should be suspected as the causative microorganism when broad-spectrum antimicrobials are ineffective.

A case of confirmed pre-symptomatic transmission of mpox.

Mpox virus is known to be transmissible from the onset of clinical manifestations. We report the first case in Japan of a man who contracted mpox through close contact with an individual with pre-symptomatic infection. Given that transmission before symptom onset has recently been reported from various countries, the importance of prophylaxis for reducing the risk of infection and controlling the disease should be emphasized.

Potential usage of anterior nasal sampling in clinical practice with three rapid antigen tests for SARS-CoV-2.

INTRODUCTION: Anterior nasal sampling (AN) might be more convenient for patients than NP sampling to diagnose coronavirus disease. This study investigated the feasibility of rapid antigen tests for AN sampling, and the factors affecting the test accuracy. METHODS: This single-center prospective study evaluated one qualitative (ESP) and two quantitative (LUMI and LUMI-P) rapid antigen tests using AN and NP swabs. Symptomatic patients aged 20 years or older, who were considered eligible for reverse-transcription quantitative polymerase chain reaction using NP samples within 9 days of onset were recruited. Sensitivity, specificity, and positive and negative concordance rates between AN and NP samples were assessed for the rapid antigen tests. We investigated the characteristics that affected the concordance between AN and NP sampling results. RESULTS: A total of 128 cases were recruited, including 28 positive samples and 96 negative samples. The sensitivity and specificity of AN samples using ESP were 0.81 and 1.00, while those of NP samples were 0.94 and 1.00. The sensitivity of AN and NP samples was 0.91 and 0.97, respectively, and specificity was 1.00, for both LUMI and LUMI-P. The positive concordance rates of AN to NP sampling were 0.87, 0.94, and 0.85 for ESP, LUMI, and LUMI-P, respectively. No factor had a significant effect on the concordance between the sampling methods. CONCLUSIONS: ESP, LUMI, and LUMI-P showed practical diagnostic accuracy for AN sampling compared to NP sampling. There was no significant factor affecting the concordance between AN and NP sampling for these rapid antigen tests.

Myeloid cell dynamics correlating with clinical outcomes of severe COVID-19 in Japan.

An expanded myeloid cell compartment is a hallmark of severe coronavirus disease 2019 (COVID-19). However, data regarding myeloid cell expansion have been collected in Europe, where the mortality rate by COVID-19 is greater than those in other regions including Japan. Thus, characteristics of COVID-19-induced myeloid cell subsets remain largely unknown in the regions with low mortality rates. Here, we analyzed cellular dynamics of myeloid-derived suppressor cell (MDSC) subsets and examined whether any of them correlate with disease severity and prognosis, using blood samples from Japanese COVID-19 patients. We observed that polymorphonuclear (PMN)-MDSCs, but not other MDSC subsets, transiently expanded in severe cases but not in mild or moderate cases. Contrary to previous studies in Europe, this subset selectively expanded in survivors of severe cases and subsided before discharge, but such transient expansion was not observed in non-survivors in Japanese cohort. Analysis of plasma cytokine/chemokine levels revealed positive correlation of PMN-MDSC frequencies with IL-8 levels, indicating the involvement of IL-8 on recruitment of PMN-MDSCs to peripheral blood following the onset of severe COVID-19. Our data indicate that transient expansion of the PMN-MDSC subset results in improved clinical outcome. Thus, this myeloid cell subset may be a predictor of prognosis in cases of severe COVID-19 in Japan.

Factors associated with high antibody titer following coronavirus disease among 581 convalescent plasma donors: A single-center cross-sectional study in Japan.

INTRODUCTION: The ability to predict which patients with a history of coronavirus disease (COVID-19) will exhibit a high antibody titer is necessary for more efficient screening of potential convalescent plasma donors. We aimed to identify factors associated with a high immunoglobulin G (IgG) titer in Japanese convalescent plasma donors after COVID-19. METHODS: This cross-sectional study included volunteers undergoing screening for convalescent plasma donation after COVID-19. Serum anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) S-protein IgG antibodies were measured using a high-sensitivity chemiluminescence enzyme immunoassay. RESULTS: IgG antibodies were measured in 581 patients, 534 of whom had full information of selected independent variables. Multiple linear regression analysis revealed that increasing age (1.037 [1,025, 1.048]), days from symptom onset to sampling (0.997 [0.995, 0.998]), fever (1.664 [1.226, 2.259]), systemic corticosteroid use during SARS-CoV-2 infection (2.382 [1.576, 3.601]), and blood type AB (1.478 [1.032, 2.117]) predict antibody titer. CONCLUSION: Older participants, those who experienced fever during infection, those treated with systemic corticosteroids during infection, those from whom samples were obtained earlier after symptom onset, and those with blood type AB are the best candidates for convalescent plasma donation. Therefore, these factors should be incorporated into the screening criteria for convalescent plasma donation after SARS-CoV-2 infection.

Fatty liver on computed tomography scan on admission is a risk factor for severe coronavirus disease.

OBJECTIVES: To alleviate the overflow of coronavirus disease 2019 (COVID-19) patients in hospitals, less invasive and simple criteria are required to triage the patients. We evaluated the relationship between COVID-19 severity and fatty liver on plain computed tomography (CT) scan performed on admission. METHODS: In this retrospective cohort study, we considered all COVID-19 patients at a large tertiary care hospital between January 31 and August 31, 2020. COVID-19 severity was categorized into severe (moderate and severe) and non-severe (asymptomatic and mild) groups, based on the Japanese National COVID-19 guidelines. Fatty liver was detected on plain CT scan. Multivariate logistic regression analysis was performed to evaluate factors associated with severe COVID-19. RESULTS: Of 222 patients (median age: 52 years), 3.2%, 58.1%, 20.7%, and 18.0% presented with asymptomatic, mild, moderate, and severe COVID-19, respectively. Although 59.9% had no fatty liver on plain CT, mild, moderate, and severe fatty liver occurred in 13.1%, 18.9%, and 8.1%, respectively. Age and presence of fatty liver were significantly associated with severe COVID-19. CONCLUSION: Our study showed that fatty liver on plain CT scan on admission can become a risk factor for severe COVID-19. This finding may help clinicians to easily triage COVID-19 patients.

Cerebral syphilitic Gumma in the modern era: a report of an unusual case and brief review of recent published reports.

BACKGROUND: Cerebral syphilitic gummas are rare. However, numerous case reports on them have been published recently, consistent with the resurgence of syphilis and its accompanying atypical manifestations. We here present a patient with a cerebral syphilitic gumma and an unusual clinical course and review recent case reports. CASE PRESENTATION: A 49-year-old woman had a generalised seizure and was found by computed tomography and magnetic resonance imaging to have a brain mass that mimicked a brain abscess or malignant tumour. Further imaging with magnetic resonance spectroscopy and positron emission tomography did not contribute further to the differential diagnosis. Because treatment with ceftriaxone was ineffective, the lesion was resected. Serological tests on serum and cerebrospinal fluid were positive for syphilis and histopathological examination of the operative specimen revealed a syphilitic gumma. Antibiotic treatment is preferred over invasive interventions for cerebral syphilitic gumma. However, as in our case, radical resection is required when antibiotic treatment is ineffective. CONCLUSIONS: It has recently been reported that the prevalence of syphilis is increasing in older individuals, including in patients without HIV infection or prior treatment for early syphilis. Though advanced imaging and molecular biological techniques are often used to help make a diagnosis, they are of limited value. Because the clinical and imaging features are nonspecific, some neurosurgeons do not include cerebral syphilitic gummas in their differential diagnoses. It is vital that this possibility be considered when a patient has a tumour-like cerebral mass and serum positivity for syphilis.

Clinical and radiological findings of silent hypoxia among COVID-19 patients.

The aim of this study was to describe the clinical and radiological findings of COVID-19 patients with "silent hypoxia," who had no dyspnea on admission even though their oximetry saturation was less than 94%. This retrospective cohort study included all COVID-19 patients (n = 270) at a large tertiary care hospital between January 31 and August 31, 2020. Clinical and radiological characteristics of patients who met our criteria of "silent hypoxia", which included those who reported no dyspnea even though oximetry saturation was <94%, were extracted. Eight patients (3.0%) met the criteria for "silent hypoxia." The median age was 61 years (interquartile range [IQR]: 48.8-72.3), and five (62.5%) were men. All patients had consolidation on CT and showed a moderate to high COVID-19 CT severity score (median: 13.5, IQR: 10.8-15.3). The median FIO2 of the maximum oxygen required was 55 (IQR: 28-70)%. Two patients (25.0%) were intubated, and one patient (12.5%) underwent extracorporeal membrane oxygenation. Some COVID-19 patients with "silent hypoxia" may develop severe disease. Close and accurate monitoring of patients using arterial blood gas and pulse oximetry is necessary, regardless of their symptoms.

Effectiveness of personal protective equipment in preventing severe acute respiratory syndrome coronavirus 2 infection among healthcare workers.

INTRODUCTION: Information on the effectiveness of personal protective equipment (PPE) for preventing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among healthcare workers (HCWs), especially among HCWs with frequent contact with patients with SARS-CoV-2, is limited. METHODS: We conducted a prospective cohort study on 49 HCWs who worked in close contact with patients with SARS-CoV-2 infection. HCWs had blood samples taken every 2 weeks to test for SARS-CoV-2 antibodies using two different types of assay. RESULTS: Forty-nine participants (31 nurses, 15 doctors, 3 other workers) were enrolled. In total, 112 blood samples are obtained from participants. The median work days in 2 weeks was 9 (interquartile range (IQR): 5-10) days. In a single work day, 30 of the 49 participants (61.5%) had contact with patients with suspected or conformed SARS-CoV-2 at least 8 times, and approximately 60% of participants had more than 10 min of contact with a single patient. The median self-reported compliance to PPE was 90% (IQR: 80-100%). Seven participants tested positive for SARS-CoV-2 antibody using enzyme-linked immunosorbent assay (ELISA); however, none were seropositive for SARS-CoV-2 neutralizing antibody, so the positive ELISA results were assumed to be false-positive. CONCLUSIONS: The study provides evidence that appropriate PPE is sufficient to prevent infection amongHCWs. It is necessary to establish a system that provides a stable supply of PPE for HCWs to perform their duties.

Direct hemoperfusion using a polymyxin B-immobilized polystyrene column for COVID-19.

OBJECTIVE: To evaluate the efficacy and safety of direct hemoperfusion using a polymyxin B-immobilized polystyrene column (PMX-DHP) in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-positive pneumonia patients. METHODS: This study was a case series conducted at a designated infectious diseases hospital. Twelve SARS-CoV-2-positive patients with partial pressure of arterial oxygen/percentage of inspired oxygen (P/F) ratio < 300 were treated with PMX-DHP on two consecutive days each during hospitalization. We defined day 1 as the first day when PMX-DHP was performed. PMX-DHP efficacy was assessed on days 7 and 14 after the first treatment based on eight categories. Subsequently, improvement in P/F ratio and urinary biomarkers on days 4 and 8, malfunctions, and ventilator and extracorporeal membrane oxygenation avoidance rates were also evaluated. RESULTS: On day 14 after the first treatment, disease severity decreased in 58.3% of the patients. P/F ratio increased while urine ß2-microglobulin decreased on days 4 and 8. Cytokine measurement pre- and post-PMX-DHP revealed decreased levels of interleukin-6 and the factors involved in vascular endothelial injury, including vascular endothelial growth factor. Twenty-two PMX-DHPs were performed, of which seven and five PMX-DHPs led to increased inlet pressure and membrane coagulation, respectively. When the membranes coagulated, the circuitry needed to be reconfigured. Circuit problems were usually observed when D-dimer and fibrin degradation product levels were high before PMX-DHP. CONCLUSIONS: Future studies are expected to determine the therapeutic effect of PMX-DHP on COVID-19. Because of the relatively high risk of circuit coagulation, coagulation capacity should be assessed beforehand.

Pyelonephritis due to Escherichia coli in the older population in Japan: Impacts on activities of daily living and medical costs.

This study aimed to investigate differences in Activities of Daily Living (ADL), at admission and discharge, as well as the medical costs of pyelonephritis in older adults in Japan. Patients hospitalized for pyelonephritis between January 1, 2013 and March 31, 2019, were retrospectively enrolled. The inclusion criteria were urine culture within 48 h of admission with > 104 colony-forming units/mL of Escherichia coli and symptoms of pyelonephritis. Patients were divided into Young (20-64 years), Pre-old (65-74 years), Old (75-84 years), and Super-old (≥ 85 years). ADL and medical costs were compared. Finally, 393 patients were included: 112 (28.5%) were Young, 72 (18.3%) were Pre-old, 130 (33.1 %) were Old, and 79 (20.1%) were Super-old between January 1, 2013, and March 31, 2019. The median differences between Barthel Index (BI) scores, which indicates ADL, at admission and discharge were 0, 0, 25, and 23 in each age group, respectively (p < 0.001). No significant differences existed between the groups aged ≥ 65. Median medical costs were $3,368, $4,894, $5,372, and $6,078 for each age group, respectively (p < 0.001). Medical costs per day did not differ significantly between the groups (p = 0.163). Pyelonephritis due to E. coli in patients aged ≥ 75 is associated with a decline in ADL, longer hospital stays, and higher medical costs compared to that in young patients. Pre-old patients did not have lower ADL; however, they tended to have longer hospital stays and higher medical costs.

Progressive Severe Hemophagocytic Syndrome due to disseminated Histoplasmosis in a Patient with HIV-1 Infection.

Histoplasmosis is caused by Histoplasma capsulatum and is prevalent in areas of the world where H. capsulatum is endemic. We herein report a patient diagnosed with HIV-1 who developed histoplasmosis from a non-H. capsulatum endemic area who experienced severe hemophagocytic syndrome due to a delayed diagnosis. The patient's symptoms emerged four years after residing in regions with a high histoplasmosis prevalence. The unrestricted administration of antifungal medication for oral candidiasis delayed the diagnosis because it improved the patient's condition. This case underscores the importance of prudent antifungal drug use in undiagnosed disseminated conditions and evaluating the travel history going back several years to facilitate a diagnosis.

Urinary liver-type fatty acid-binding protein level as a prognostic indicator of acute kidney injury secondary to severe falciparum malaria.

Acute kidney injury (AKI) secondary to severe falciparum malaria possesses a high mortality rate; however, a prognostic marker of renal dysfunction has not yet been identified. Thus, we reported a case of a patient with AKI secondary to falciparum malaria who underwent hemodialysis and a renal biopsy due to prolonged renal dysfunction. The male patient, in his 50 s, presented to our hospital with vomiting, diarrhea, fever, and decreased level of consciousness. The Giemsa-stained peripheral blood film revealed approximately 5% parasitemia, and a rapid diagnostic test was positive for Plasmodium falciparum. He was diagnosed with severe falciparum malaria and was started on quinine hydrochloride. Hemodialysis was initiated due to the decreased urine output and fluid retention. Subsequently, he was weaned off hemodialysis. The histopathological analysis of a renal biopsy revealed interstitial fibrosis, tubular atrophy, and chronic inflammatory cell infiltration; thus, malarial nephropathy was diagnosed. Thereafter, his renal function stabilized, and he was discharged from the hospital. The urinary liver-type fatty acid-binding protein (L-FABP) level decreased before renal function improved. Our report highlighted that long-term follow-up is essential for severe AKI secondary to malaria. The urinary L-FABP level may be a useful prognostic indicator of AKI secondary to severe falciparum malaria.

Exacerbations of Idiopathic Systemic Capillary Leak Syndrome following BNT162b2 mRNA COVID-19 Vaccine (Pfizer-BioNTech).

A Japanese man experienced three episodes of hypovolemic shock and was diagnosed with systemic capillary leak syndrome (SCLS). He developed SCLS exacerbation 2 days after receiving a second dose of the Pfizer-BioNTech BNT162b2 mRNA COVID-19 vaccine, 1 year after the third episode. After fluid therapy and albumin administration, we initiated terbutaline and theophylline prophylaxis for SCLS. A literature review revealed that SCLS attacks often occur 1-2 days after the second COVID-19 vaccination. Patients with a history of SCLS should avoid COVID-19 vaccination and be carefully monitored for 1-2 days if they receive the vaccine.