Recombinant thrombomodulin attenuates hyper-inflammation and glycocalyx damage in a murine model of Streptococcus pneumoniae-induced sepsis.

PURPOSE: The anticoagulant agent recombinant thrombomodulin (rTM) activates protein C to prevent excessive coagulation and also possibly regulates hyper-inflammation via neutralization of high-mobility-group B1 (HMG-B1). The glycocalyx layer in endothelial cells also plays a pivotal role in preventing septic shock-associated hyperpermeability. The present study examined the effect of rTM in a murine model of Streptococcus pneumoniae-induced sepsis. METHODS: Male C57BL/6N mice were injected intratracheally via midline cervical incision with 2 × 107 CFU of S. pneumoniae (capsular subtype 19A). Control mice were sham-treated identically but injected with saline. rTM (10 mg/kg) was injected intraperitoneally 3 h after septic insult. Blood concentrations of soluble inflammatory mediators (interleukin [IL]-1ß, IL-6, IL-10, and tumor necrosis factor [TNF]-α) were determined using a microarray immunoassay. Serum concentrations of HMG-B1 and syndecan-1, as a parameter of glycocalyx damage, were determined by enzyme-linked immunosorbent assay. The glycocalyx was also evaluated with electron microscopy. The lungs were removed, and digested to cells, which were then stained with a mixture of fluorophore-conjugated antibodies. Anti-mouse primary antibodies included PE-Cy7-conjugated anti-CD31, AlexaFluor 700-conjugated anti-CD45, PerCP-Cy5.5-conjugated anti-CD326, APC-conjugated anti-TNF-α, PE-conjugated anti-IL-6, and PE-conjugated anti-IL-10. A total of 1 × 106 cells per sample were analyzed, and 2 × 105 events were recorded by flow cytometry, and parameters were compared with/without rTM treatment. RESULTS: The blood concentration of TNF-α was significantly reduced 24 h after intratracheal injection in S. pneumoniae-challenged mice treated with rTM (P = 0.016). Levels of IL-10 in the lung endothelium of rTM-treated S. pneumoniae-challenged mice increased significantly 12 h after intratracheal injection (P = 0.03). Intriguingly, serum HMGB-1 and syndecan-1 levels decreased significantly (P = 0.010 and 0.015, respectively) in rTM-treated mice 24 h after intratracheal injection of S. pneumoniae. Electron microscopy indicated that rTM treatment preserved the morphology of the glycocalyx layer in septic mice. CONCLUSIONS: These data suggest that rTM modulates local inflammation in the lung endothelium, thus diminishing systemic inflammation, i.e., hypercytokinemia. Furthermore, rTM treatment reduced serum syndecan-1 levels, thus preventing glycocalyx damage. The use of rTM to treat sepsis caused by bacterial pneumonia could therefore help prevent both excessive inflammation and glycocalyx injury in the lung endothelium.

Epidemiological characteristics in serotype 24 paediatric invasive pneumococcal disease according to an 11-year population-based study in Japan.

After the introduction of the 13-valent pneumococcal conjugate vaccine (PCV13), serotype replacement has occurred in Japan, and serotype 24 has become the most common serotype in paediatric invasive pneumococcal disease (IPD). To understand the characteristics of serotype 24-IPD in Japanese children in the post-PCV13 era, we conducted a retrospective study in children aged ≤15 years from 2010 to 2020 using a database of paediatric IPD surveillance in Chiba prefecture, Japan. We identified a total of 357 IPD cases and collected clinical information on 225 cases (24: 32 cases, non-24: 193 cases). Compared with the non-serotype 24-IPD, serotype 24-IPD was independently related to be <2 years of age [odds ratio (OR) 3.91, 95% confidence interval (CI) 1.47-10.44; P = 0.0064] and bacteremia (OR 2.28, 95% CI 1.01-5.13; P = 0.0475), as a result of the multivariate regression analysis. We also conducted a bacterial analysis, and the isolates of serotype 24-IPD had tendencies of PCG-susceptible (24: 100.0%, non-24: 61.3%; P < 0.0001) and macrolide-resistance (24: 100.0%, non-24: 87.3%; P = 0.0490). Their multilocus sequence typing was mostly ST2572 and the variants, which were unique to Japan. This tendency might have been a result of the progress made in the Japanese PCV13 immunisation programme.

Epidemiology and bacterial characteristics of invasive group B streptococcus disease: a population-based study in Japan in 2010-2020.

This is the first report on a population-based prospective study of invasive group B streptococcus (GBS) disease among children aged <15 years conducted over a period of 11 years in Japan. This study investigated the incidence and clinical manifestations of invasive GBS disease in children in Chiba Prefecture, Japan, and analysed the serotypes and drug susceptibility of GBS strains isolated during the study period. Overall, 127 episodes of invasive GBS disease were reported in 123 patients. Of these, 124 were observed in 120 patients aged <1 year, and the remaining three episodes were reported in a 9-year-old child and two 14-year-old children with underlying disease. For patients aged <1 year, the incidence rate per 1000 live births was 0.24 (0.15-0.36). The incidences of early-onset disease and late-onset disease were 0.04 (0.0-0.09) and 0.17 (0.08-0.25), respectively. The rate of meningitis was 45.2%, and the incidence of GBS meningitis was higher than that of other invasive diseases among children in Japan. Of the 109 patients for whom prognosis was available, 7 (6.4%) died and 21 (19.3%) had sequelae. In total, 68 strains were analysed. The most common were serotype III strains (n = 42, 61.8%), especially serotype III/ST17 strains (n = 22, 32.4%). This study showed that the incidence of invasive GBS disease among Japanese children was constant during the study period. Because of the high incidence of meningitis and disease burden, new preventive strategies, such as GBS vaccine, are essential.

The clinical characteristics of pediatric coronavirus disease 2019 in 2020 in Japan.

BACKGROUND: The COVID-19 pandemic has affected the lives of people of all ages. Most reports on pediatric cases suggest that children experience fewer and milder symptoms than do adults. This is the first nationwide study in Japan focusing on pediatric cases reported by pediatricians, including cases with no or mild symptoms. METHODS: We analyzed the epidemiological and clinical characteristics and transmission patterns of 840 pediatric (<16 years old) COVID-19 cases reported between February and December 2020 in Japan, using a dedicated database which was maintained voluntarily by members of the Japan Pediatric Society. RESULTS: Almost half of the patients (47.7%) were asymptomatic, while most of the others presented mild symptoms. At the time of admission or first outpatient clinic visit, 84.0% of the cases were afebrile (<37.5°C). In total, 609 cases (72.5%) were exposed to COVID-19-positive household members. We analyzed the influence of nationwide school closures that were introduced in March 2020 on COVID-19 transmission routes among children in Japan. Transmission within households occurred most frequently, with no significant difference between the periods before and after declaring nationwide school closures (70.9% and 74.5%, respectively). CONCLUSIONS: COVID-19 symptoms in children are less severe than those in adults. School closure appeared to have a limited effect on transmission. Controlling household transmission from adult family members is the most important measure for prevention of COVID-19 among children.

First report on multidrug-resistant non-encapsulated Streptococcus pneumoniae isolated from a patient with pneumonia.

The non-encapsulated Streptococcus pneumoniae (NESp) has emerged and increased in the clinical setting. The majority of NESp strains have been isolated from the nasopharynxes of healthy carriers and from respiratory specimens of patients with otitis media. NESp strains were shown to be more effective than encapsulated counterparts at forming biofilms. Therefore, NESp should become one of the leading causes of emerging refractory respiratory disease after the introduction of pneumococcal conjugate vaccines. We report the first case of multidrug-resistant - including fluoroquinolone-resistant - NESp isolated from the intrabronchial aspirate of a patient with pneumonia. Drug-resistant NESp infections can possibly emerge as a clinical problem and thus the continuous monitoring of NESp infections is of utmost importance.

Haemophilus influenzae type b capsular polysaccharide antibody levels in Japanese young patients with hematological malignancies and asplenia.

Individuals with immunosuppressive condition have a high risk of invasive Haemophilus influenzae type b (Hib) infection. In Japan, routine Hib vaccination program for children under 5 years old was introduced in December 2008. However, the national policy does not make provision for individuals aged ≥5 years who have medical conditions associated with a high risk of invasive Hib disease to receive Hib vaccine. We measured serum anti-polyribosylribitol phosphate specific (anti-PRP) antibodies to Hib in patients aged ≥5 years with hematological malignancies and asplenia and evaluated their levels of anti-PRP antibodies in post administration of Hib vaccine era. A total of 65 patients (48 with hematological malignancies, and 17 with asplenia) were included in this study, of which 84% had not received Hib vaccine. In addition, 95.4% had short-term protective levels of anti-PRP antibodies (defined as ≥0.15 µg/mL) and 41.5% had long-term protective levels of anti-PRP antibodies (defined as ≥1.0 µg/mL). Five patients had low anti-PRP antibody levels despite a history of Hib vaccination. Our results suggest that young patients with underlying diseases such as hematological malignancies and asplenia may be at risk of invasive Hib disease. Hence, we recommend they should receive Hib vaccines even if they are over the age limit for routine Hib vaccination program.

Two pediatric cases of Pneumocystis jirovecii pneumonia diagnosed by polymerase chain reaction of gastric lavage.

Detecting Pneumocystis jirovecii by bronchoalveolar lavage or lung biopsy is the gold standard for diagnosis of P. jirovecii pneumonia (PJP); however, these techniques are not always applicable in children because of their high invasiveness. We report two pediatric cases of PJP diagnosed by polymerase chain reaction (PCR) of gastric lavage that were successfully treated. To date, there are no reported cases of using PCR of gastric lavage to diagnose PJP. On the day of PJP onset, both the infants required respiratory support and infiltrative shadows were observed in both lung fields on chest radiography. Furthermore, their (1 â†’ 3)-ß-D glucan levels were elevated. P. jirovecii was detected by PCR of gastric lavage and trimethoprim-sulfamethoxazole was administered for 3 weeks, following which their condition improved. They were long-term steroid users, but without any prophylaxis. PCR of gastric lavage in cases of suspected PJP may help in confirming the diagnosis in children who have mild to moderate airway symptoms, or have difficulty with invasive examination like bronchoscopy.

Psoitis and multiple venous thromboses caused by Panton Valentine Leukocidin-positive methicillin-sensitive Staphylococcus aureus in a 12-year-old girl: A case report.

Panton Valentine Leukocidin (PVL) is one of the many toxins produced by Staphylococcus aureus. In Japan, PVL-positive S. aureus strains are mainly methicillin-resistant S. aureus (MRSA). Data regarding PVL-positive methicillin-sensitive S. aureus (MSSA) are scarce. In this report, we describe a case of severe infection by PVL-positive MSSA. A 12-year-old healthy girl was admitted with high fever and pain in the lower back. Computed tomography revealed a diagnosis of psoitis and multiple venous thromboses. Blood cultures obtained after admission revealed infection with MSSA. Her fever continued despite adequate antibiotic therapy. On the fifth hospitalization day, she developed bladder dysfunction, and an abscess was noted near the third lumbar vertebra. She underwent an emergency operation and recovered. Bacterial analyses revealed that the causative MSSA was a PVL-producing single variant of ST8 (related to USA300clone), of sequence type 2149. PVL is known to cause platelet activation. This case demonstrates the need for detailed analyses of the causative strain of bacteria in cases of S. aureus infection with deep vein thrombosis, even in cases of known MSSA infection.

The First Case of Invasive Mixed-Mold Infections Due to Emericella nidulans var. echinulata and Rasamsonia piperina in a Patient with Chronic Granulomatous Disease.

A 16-year-old boy with chronic granulomatous disease presented with pneumonia and rib osteomyelitis. Emericella nidulans var. echinulata was isolated from his sputum. After starting voriconazole, Rasamsonia piperina was isolated from the rib swelling. A combination therapy of voriconazole and micafungin effectively eradicated this invasive mixed-mold infection. In immunocompromised patients, a precise pathogenic diagnosis is clinically useful for administration of an appropriate treatment regimen.

[Comparison of the clinical effectiveness of three neuraminidase inhibitors for Japanese pediatric patients with influenza in the 2013/2014 season].

We investigated the clinical symptoms of 206 pediatric patients with influenza virus infection and compared them among oseltamivir-treated, zanamivir-treated, and laninamivir-treated groups in 2013/2014 influenza season. The drug compliance of each neuraminidase inhibitor was good in all three groups. Although the duration of fever after administration of the first dose of each neuraminidase inhibitor were significantly prolonged in the patient with influenza B infection than in the patient with influenza A infection, no statistically significant difference in the clinical efficacy and the side effect among three groups were found. The number of biphasic fever episodes in patients treated with neuraminidase inhibitor was rare (two episodes of oseltamivir-treated group and one episode of zanamivir-treated group). In conclusion, under the good drug compliance, the efficacy of all three neuraminidase inhibitor was the same for the treatment of influenza virus infection in children.

IgG levels against 13-valent pneumococcal conjugate vaccine serotypes in non pneumococcal conjugate vaccine immunized healthy Japanese and intravenous immunoglobulin preparations.

No studies showed specific antibody levels against all serotypes covered by 13-valent pneumococcal conjugate vaccine (PCV13) among polyclonal intravenous immunoglobulin (IVIG) products. Our study aimed to assess whether we could expect the efficacy of IVIG therapy for invasive pneumococcal disease (IPD) and to clarify the age group which should be recommended for IVIG therapy in case of IPD. Serotype-specific immunoglobulin G (IgG) levels against PCV13 serotypes were measured in four IVIGs which were produced from Japanese donors who were not immunized with any pneumococcal conjugate vaccines (PCVs), and in the serum of 160 non-PCV immunized Japanese subjects, by enzyme-linked immunosorbent assay. The functional opsonic activities of the IVIGs against serotypes 6B and 19A were assessed by a multiplexed opsonophagocytic killing assay. Japanese infants aged <2 years had a geometric mean IgG concentration of <0.35 µg/ml against several serotypes. Serotype-specific IgG concentrations varied among IVIGs. In general, IgG antibodies against serotypes 6A, 14 and 19A were higher in each IVIG. Although opsonization indices also varied among preparations, each IVIG had the ability to opsonize both serotypes 6B and 19A. This study suggests that routine immunization with PCV is important for prevention of IPD, especially for children <2 years old and IVIGs might be effective for IPD patients.

An immunocompetent child with chromosomally integrated human herpesvirus 6B accidentally identified during the care of Mycoplasma pneumoniae infection.

Human herpesvirus 6 (HHV-6) is the only virus known to integrate into human chromosomes and be transmitted from parents to offspring. Less than 1% of the population carries integrated HHV-6 in their genomes. Here, we report the case of a 9-year-old Japanese girl with an extraordinarily high copy number of HHV-6B in her genome. The integrated virus genome was detected by real-time polymerase chain reaction (PCR) in cerebrospinal fluid and serum during the treatment of meningoencephalitis and pneumonia caused by Mycoplasma pneumoniae infection. Furthermore, the HHV-6B genome was detected in hair follicle, plasma, and whole blood in the patient and her mother, but not in the patient's father. Fluorescence in situ hybridization revealed that the viral genome was integrated into chromosome 22. Therefore, these results emphasize the importance of screening for chromosomally integrated HHV-6 prior to starting unnecessary antiviral therapies, particularly for patients harboring HHV-6 with a high copy number.

Changes in nasopharyngeal carriage of Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis among healthy children attending a day-care centre before and after official financial support for the 7-valent pneumococcal conjugate vaccine and H. influenzae type b vaccine in Japan.

The 7-valent pneumococcal conjugate vaccine (PCV7) and Haemophilus influenzae type b (Hib) vaccine reduce nasopharyngeal carriage of vaccine-type bacteria, which may in turn influence the presence of other nasopharyngeal bacterial pathogens. To investigate this possibility, nasopharyngeal carriage of potential pathogens was examined before and after official financial support was provided to offer the PCV7 and Hib vaccines in healthy children attending a day care centre in Japan during 2011-2012. Despite a virtual disappearance of PCV7 serotypes over time, the overall pneumococcal carriage rate remained unchanged. Although others have reported an increase in PCV13 serotypes following PCV7 vaccination, only non-PCV13 serotypes were observed to have increased in this study. The majority of H. influenzae isolates were non-typeable and Hib was not found. Our data identified an unexpected pattern of pneumococcal serotype replacement following PCV7. Continuous monitoring of pneumococcal carriage is important for decisions regarding the future of national vaccination policy in Japan.

Streptococcus gallolyticus subsp. pasteurianus meningitis in an infant.

Streptococcus gallolyticus subsp. pasteurianus was formerly classified as S. bovis biotype II/2, which is recognized as a rare cause of neonatal sepsis and meningitis. Since the taxonomy classification change, there have not been many reports of meningitis due to S. gallolyticus subsp. pasteurianus. Moreover, the pathogenesis of late onset S. gallolyticus subsp. pasteurianus meningitis in infants is unclear. Here we report a case of meningitis in a 5-week-old infant with preceding diarrhea. S. bovis biotype II/2 was isolated from the blood, cerebrospinal fluid and stool, and then was identified as S. gallolyticus subsp. pasteurianus on 16S rRNA gene sequencing. Isolates from all three sample types had identical profiles on pulsed-field gel electrophoresis. The intestinal tract was thought to be the source of the infection.

The prebiotic effect of 1-kestose in low-birth-weight neonates taking bifidobacteria: a pilot randomized trial in comparison with lactulose.

Probiotics such as bifidobacteria have been given to low-birth-weight neonates (LBWNs) at risk for a disrupted gut microbiota leading to the development of serious diseases such necrotizing enterocolitis. Recently prebiotics such as lactulose are used together with bifidobacteria as synbiotics. However, faster and more powerful bifidobacteria growth is desired for better LBWN outcomes. The prebiotic 1-kestose has a higher selective growth-promoting effect on bifidobacteria and lactic acid bacteria in vitro among several oligosaccharides. Twenty-six premature neonates (less than 2,000 g) admitted to a neonatal intensive care unit (NICU) were randomly assigned to receive Bifidobacterium breve M16-V with either 1-kestose or lactulose once a day for four weeks from birth. A 16S rRNA gene analysis revealed similar increases in alpha-diversity from 7 to 28 days in both groups. The most dominant genus on both days was Bifidobacterium in both groups, with no significant difference between the two groups. Quantitative PCR analysis revealed that the number of Staphylococcus aureus tended to be lower in the 1-kestose group than in the lactulose group at 28 days. The number of Escherichia coli was higher in the 1-kestose group at 7 days. The copy number of total bacteria in the 1-kestose group was significantly higher than that in the lactulose group at 3 time points, 7, 14, and 28 days. No severe adverse events occurred in either group during the study period. l-Ketose may offer an alternative option to lactulose as a prebiotic to promote the development of gut microbiota in LBWNs.

Effect of multi-strain bifidobacteria supplementation on intestinal microbiota development in low birth weight neonates: a randomized controlled trial.

Single-strain Bifidobacterium species are commonly used as probiotics with low birth weight neonates. However, the effectiveness and safety of multi-strain Bifidobacterium supplementation are not well known. Thirty-six neonates weighing less than 2,000 g (558-1,943 g) at birth and admitted to a neonatal intensive care unit were randomly assigned to receive a single strain or triple strains of Bifidobacterium with lactulose enterally for 4 weeks from birth. The relative abundances of Staphylococcus and Bifidobacterium in the fecal microbiota at weeks 1, 2, and 4 were investigated. Based on the study results, no significant difference was detected between the two groups in the abundance of Staphylococcus; however, the triple-strain group had significantly high abundances of Bifidobacterium at weeks 2 and 4. The fecal microbiota in the triple-strain group had significantly lower alpha diversity (Bifidobacterium-enriching) after week 4 and was different from that in the single-strain group, which showed a higher abundance of Clostridium. No severe adverse events occurred in either group during the study period. Although no significant difference was detected between single- and multi-strain bifidobacteria supplementation in the colonization of Staphylococcus in the fecal microbiota of the neonates, multi-strain bifidobacteria supplementation contributed toward early enrichment of the microbiota with bifidobacteria and suppression of other pathogenic bacteria, such as Clostridium spp.

Prospective hospital-based cohort studies of Respiratory Syncytial Virus (RSV) infections in infants under one year during and after the SARS-CoV-2 pandemic in Japan.

OBJECTIVES: In Japan, population-based epidemiological data on respiratory syncytial virus (RSV) infections are limited. To elucidate the epidemiology of RSV before the introduction of new prophylactic drugs, we conducted a population-based study during and after the SARS-CoV-2 pandemic. METHODS: This study was performed in four hospitals in Chiba City and three hospitals in Ichihara City. Clinical information and residual samples from RSV rapid antigen tests of infants under one year old were collected. Samples from patients with lower respiratory tract infections (LRTI) were analyzed using the FilmArray Respiratory 2.1 panels. RESULTS: A total of 1200 infants underwent the RSV rapid antigen test, with 497 diagnosed with LRTI. Although five samples could not be stored, 252 out of 492 (51.2%) were positive for RSV. Among the RSV PCR-positive infants, 63 (25.0%) had underlying diseases, compared to 100 out of 240 (41.7%) RSV PCR-negative infants (p < 0.05). In Chiba City, the annual incidence of hospitalization per 1000 children was 12.7 in 2021, 4.4 in 2022, and 9.2 in 2023. CONCLUSIONS: During and after the SARS-CoV-2 pandemic, most hospitalized infants with RSV-LRTI did not have underlying diseases. Widespread use of prophylaxis in infants without underlying disease is desirable.

Isoniazid- and streptomycin-resistant miliary tuberculosis complicated by intracranial tuberculoma in a Japanese infant.

In Japan, the incidence of severe pediatric tuberculosis (TB) has decreased dramatically in recent years. However, children in Japan can still have considerable opportunities to contract TB infection from adult TB patients living nearby, and infants infected with TB may develop severe disseminated disease. A 3-month-old girl was admitted to our hospital with dyspnea and poor feeding. After admission, miliary TB and multiple brain tuberculomas were diagnosed. Anti-tuberculous therapy was initiated with streptomycin (SM), isoniazid (INH), rifampicin and pyrazinamide. Symptoms persisted after starting the initial treatment and mycobacterial cultures of gastric fluid remained positive. Drug sensitivity testing revealed the TB strain isolated on admission as completely resistant to INH and SM. Treatments with INH and SM were therefore stopped, and treatment with ethambutol and ethionamide was started in addition to rifampicin and pyrazinamide. After this change to the treatment regimen, symptoms and laboratory data gradually improved. The patient was treated with these four drugs for 18 months, and then pyrazinamide was stopped. After another 2 months, ethambutol was stopped. Treatment of tuberculosis was completed in 24 months. No adverse effects of these anti-TB drugs were observed. The patient achieved a full recovery without any sequelae. On the other hand, the infectious source for this patient remained unidentified, despite the extensive contact investigations. The incidence of drug-resistant TB is increasing in many areas of the world. Continuous monitoring for pediatric patients with drug-resistant TB is therefore needed.

Real-world efficacy and safety of glecaprevir/pibrentasvir in Japanese adolescents with chronic hepatitis C: a prospective multicenter study.

BACKGROUND: Part 1 of the DORA study, a 2019 international clinical trial of glecaprevir and pibrentasvir (G/P) treatment in adolescents with chronic hepatitis C virus (HCV) infection, demonstrated high efficacy and safety. However, few reports have considered real-world experience with G/P treatment in adolescents with chronic HCV. The present prospective multicenter study assessed real-world efficacy and safety of G/P treatment in Japanese adolescents with chronic HCV. METHODS: Subjects between 12 and 17 years old who were treatment-naïve or previously managed with interferon-based regimens were prospectively enrolled and treated with G/P (300 mg/120 mg) once daily for 8 or 12 weeks. The primary efficacy endpoint was sustained virologic response at 12 weeks after treatment completion (SVR12). Adverse effects and laboratory abnormalities were assessed. RESULTS: Twenty-five Japanese patients (15 female) were enrolled from 13 pediatric centers in Japan. Median age was 13 years (range 12-17). Numbers of patients with genotypes 1b, 2a, 2b, and 2b/1b were 6, 12, 6, and 1, respectively. Twenty-two were treatment-naïve, while three had experienced interferon-based treatments. All patients completed G/P treatment (24 for 8 weeks and 1 for 12). Twenty-four achieved SVR12 (96%). Most adverse events were mild. None were serious. G/P significantly decreased serum alanine aminotransferase, γ-glutamyltransferase, and Wisteria floribunda agglutinin-positive Mac-2-binding protein concentrations. No negative effects on growth or maturation were apparent at 12 weeks. CONCLUSIONS: Under real-world conditions, G/P treatment of Japanese adolescents with chronic HCV was highly efficacious and well tolerated.