[Clinical Characteristics of Invasive Pneumococcal Disease of the Mucoid Phenotype: A Case Series].

Streptococcus pneumoniae is a gram-positive coccus that causes invasive and non-invasive pneumococcal diseases. Invasive pneumococcal disease (IPD) is defined as an infection confirmed by the isolation of S. pneumoniae from a normally sterile site. IPD has a high mortality rate of around 20% in adults. Colonies of S. pneumoniae show various morphological features which include a mucoid appearance. The production of large amounts of capsular polysaccharide gives colonies of S. pneumoniae their mucoid appearance. This is thought to be a mechanism of microbial escape from phagocyte killing, leading to strong pathogenicity despite their high susceptibility to antibiotics. To our knowledge, the clinical characteristics of patients with mucoid IPD are unknown. We retrospectively analyzed the records of adult patients with IPD of the mucoid phenotype at Teine Keijinkai Hospital, Hokkaido, Japan, between 2009 and 2015. Seven patients (six males) with age range between 62 and 80 years were diagnosed as having mucoid IPD during the study period. Two patients had a history of malignancy and diabetes mellitus respectively, and six patients were living independently. No patients were previously vaccinated with pneumococcal vaccine. Six patients had clinical manifestations of pneumonia; one patient had multiple concomitant complications of mastoiditis, meningitis, and prosthetic joint infection. All isolates were isolated from blood. All isolates were susceptible to beta-lactam antibiotics, while six isolates were resistant to macrolides and chloramphenicol. Based on the Quellung reaction and real-time polymerase chain reaction (PCR) results, one isolate of mucoid phenotype was confirmed as serotype 3 with the penicillin binding protein gene of pbp2x and the macrolide resistant gene of ermB. Although all patients received appropriate antibiotics based on susceptibility testing, four patients required mechanical ventilation and vasopressors. One patient had neurological sequelae (hypacusis) and two patients died during the course of hospitalization. This case series suggests that mucoid IPD can occur in immunocompetent hosts and can cause high mortality. Since most of the mucoid phenotype of S. pneumoniae are serotype 3, widespread use of pneumococcal vaccine is important to prevent morbidity and mortality associated with IPD.

Multiple lung abscesses and cold agglutinin syndrome following coronavirus disease 2019: a case report.

BACKGROUND: Cold agglutination syndrome is a subtype of autoimmune hemolytic anemia. The condition is referred to as "cold" because the antibodies become active and induce hemolysis at cold temperatures, typically 3-4 °C, which is not always the case in other kinds of autoimmune hemolytic anemia. Whereas primary cold agglutination syndrome may occur in the absence of underlying conditions, secondary cold agglutination syndrome is associated with the presence of underlying infections, including coronavirus disease 2019. CASE PRESENTATION: We report the case of a 69-year-old Japanese woman with periodontitis who was referred to our hospital with complaints of brown-colored urine and chest pain. Her hemoglobin level was 6.1 g/dL. Computed tomography revealed multiple lung abscesses. Her direct antibody test results were positive (2+) for anti-complement direct antiglobulin and negative for immunoglobulin G, and her cold agglutinin titer was elevated at 1:4096. Workup for anemia revealed a positive result for cold agglutination syndrome. The patient had received the fourth dose of coronavirus disease 2019 vaccination. Nasopharyngeal swab test for detecting severe acute respiratory syndrome coronavirus 2 using a real-time reverse-transcription polymerase chain reaction gave a cycle threshold value of 42.3, and the level of virus-specific immunoglobulin G was elevated at 7.71 S/C (normal range -1.4 S/C). CONCLUSION: A decrease in hemoglobin in patients with coronavirus disease 2019 may be associated with secondary cold agglutination syndrome. The patient was hypothesized to have developed multiple lung abscesses with secondary cold agglutination syndrome following coronavirus disease 2019. Thus, following coronavirus disease 2019, patients can develop secondary cold agglutination syndrome, which could worsen owing to associated bloodstream bacterial infections.

Effectiveness of primary series, first, and second booster vaccination of monovalent mRNA COVID-19 vaccines against symptomatic SARS-CoV-2 infections and severe diseases during the SARS-CoV-2 omicron BA.5 epidemic in Japan: vaccine effectiveness real-time surveillance for SARS-CoV-2 (VERSUS).

BACKGROUND: This study aimed to evaluate VE of primary, first, and second booster ancestral-strain monovalent mRNA COVID-19 vaccination against symptomatic infections and severe diseases in Japan. METHODS: We conducted a test-negative case-control study. We included medically attended episodes and hospitalizations involving individuals aged ≥16 with signs and symptoms from July to November 2022, when Omicron BA.5 was dominant nationwide. To evaluate VE, we calculated adjusted ORs of vaccination among test-positive versus test-negative individuals using a mixed-effects logistic regression. RESULTS: For VE against symptomatic infections among individuals aged 16 to 59, VE of primary vaccination at > 180 days was 26.1% (95% CI: 10.6-38.8%); VE of the first booster was 58.5% (48.4-66.7%) at ≤90 days, decreasing to 41.1% (29.5-50.8%) at 91 to 180 days. For individuals aged ≥60, VE of the first booster was 42.8% (1.7-66.7%) at ≤90 days, dropping to 15.4% (-25.9-43.2%) at 91 to 180 days, and then increasing to 44.0% (16.4-62.5%) after the second booster. For VE against severe diseases, VE of the first and second booster was 77.3% (61.2-86.7%) at ≤90 days and 55.9% (23.4-74.6%) afterward. CONCLUSION: mRNA booster vaccination provided moderate protection against symptomatic infections and high-level protection against severe diseases during the BA.5 epidemic in Japan.

Listeria monocytogenes Ankle Osteomyelitis in a Patient with Rheumatoid Arthritis on Adalimumab: A Report and Literature Review of Listeria monocytogenes Osteomyelitis.

Localized Listeria infection predominantly occurs in the prosthetic and hip joints. We herein report a case of Listeria monocytogenes ankle osteomyelitis in a 73-year-old man receiving adalimumab who was transferred to our hospital because of suspected rheumatoid arthritis (RA) flare. He reported a four-month history of left ankle swelling. A surgical biopsy revealed L. monocytogenes osteomyelitis in the left tibia and talus bones. The patient was successfully treated with antibiotics and surgical debridement. Thus, infection due to L. monocytogenes can present as ankle osteomyelitis in immunocompromised patients and may mimic an RA flare.

Legionella pneumophila pneumonia with rapid clinical course in a lung cancer patient.

We report an acute clinical course of pneumonia caused by Legionella pneumophila in a patient receiving chemotherapy for lung cancer and corticosteroid therapy. A 57-year-old man presented with fever and dyspnoea and was admitted to our hospital. Chest computed tomography revealed a new left lower lung infiltrate, tumour progression in the right upper lung region, metastases to lymph nodes and pleural effusion. The urinary antigen test for Legionella was positive. The patient's oxygen requirement increased on the day of admission, and he died the day after hospitalization. Legionnaires' disease may manifest with an acute presentation, and patients in Japan with physical risk factors for this disease could get infected despite the absence of environmental risk factors. Early treatment for suspected Legionnaire's disease should be considered.

Association of early antibiotic therapy and in-hospital mortality in adult mild-to-moderate acute aspiration pneumonitis: a cohort study.

BACKGROUND: Patients with aspiration pneumonitis often receive empiric antibiotic therapy despite it being due to a non-infectious, inflammatory response. OBJECTIVE: To study the benefits of early antibiotic therapy in patients with suspected aspiration pneumonitis in an acute care hospital. DESIGN: Retrospective cohort study using electronic medical records from Teine Keijinkai Hospital. PARTICIPANTS: Adults aged over 18 years admitted with a diagnosis of aspiration pneumonitis to the Department of General Internal Medicine or Emergency Department between January 1, 2008, and May 31, 2019. A diagnosis of aspiration pneumonitis was defined as a documented macro-aspiration event and a chest radiograph demonstrating new radiographic infiltrates. MAIN MEASURES: Patients were classified into the "early antibiotic treatment" group and the "no or late treatment" group depending on whether they received antibiotic therapy for respiratory bacterial pathogens within 8 h of arrival. The primary outcome was in-hospital all-cause mortality. Secondary outcomes included length of hospital stay, antibiotic-free days, duration of fever, readmission within one month, and incidence of complications. KEY RESULTS: Of the 146 patients enrolled, 52 (35.6%) did not receive early antibiotic therapy, while the remaining 94 (64.4%) did. There was no difference in in-hospital mortality rates between the groups after adjustment for potential confounding variables using Cox proportional hazards analysis (hazard ratio 2.78; 95% confidence interval, 0.57-13.50, p = 0.20). Patients in the no or late treatment group had more antibiotic-free days (p < 0.001) and a shorter length of hospital stay among survivors (p = 0.040) than did those in the early antibiotic treatment group. There were no statistically significant differences between the groups with respect to other secondary outcomes. CONCLUSIONS: Early antibiotic therapy for acute aspiration pneumonitis was not associated with in-hospital mortality, but was associated with a longer hospital stay and prolonged use of antibiotics.

The first case of COVID-19 occurring as community-acquired pneumonia in Hokkaido, Japan and our preventive measures against nosocomial infection.

We report a case of a 59-year-old man with coronavirus disease 2019 (COVID-19). He had visited a hospital for fever and cough and been treated with antibiotics for pneumonia in the right upper lobe. However, he gradually progressed to dyspnea and consulted our hospital. His chest radiographs showed bilateral pneumonia shadows and his CT showed ground glass opacities and consolidation. Although we treated him with broad-spectrum antibiotics, the pneumonia shadow rapidly progressed and mechanical ventilation was administered. We collected sputum from the bronchus using bronchoscopy to detect microorganisms, and RT-PCR tests confirmed COVID-19 pneumonia. He was transferred to a designated hospital. In order to prevent the occurrence of nosocomial infections, close contacts within the hospital and medical staff were suspended from their work for two weeks. No secondary infection with COVID-19 appeared. This was the first case of COVID-19 occurring as community-acquired pneumonia in Hokkaido, Japan.

Culture-negative group B streptococcal pericarditis: A case report and literature review of the diagnostic use of polymerase chain reaction.

Although conventional microbiology cultures may be negative, polymerase chain reaction (PCR) can effectively identify both typical and atypical microorganisms. With careful interpretation, PCR could become the gold-standard diagnostic test for culture-negative bacterial pericarditis.

Tracking the Clonal Evolution of Adenosquamous Carcinoma, a Rare Variant of Intraductal Papillary Mucinous Neoplasm of the Pancreas.

Adenosquamous carcinoma (ASC) is an uncommon variant of pancreatic neoplasm. We sought to trace the mode of tumor progression using specimens of ASC associated with intraductal papillary mucinous neoplasm (IPMN) of the pancreas. A resected specimen of the primary pancreatic ASC, developed in a 72-year-old man, was subjected to mutation profiling using amplicon-targeted sequencing and digital polymerase chain reaction. DNA was isolated from each histological compartment including noninvasive IPMN, squamous cell carcinoma (SCC), and adenocarcinoma (AC). Histologically, an IPMN with a large mural nodule was identified. The invasive tumor predominantly consisted of SCC, and a smaller AC was found around the lesion. Squamous metaplasias were sporadically distributed within benign IPMNs. Mutation alleles KRAS and GNAS were identified in all specimens of IPMN including the areas of squamous metaplasia. In addition, these mutations were found in SCC and AC. Clear transition from flat/low-papillary IPMN to SCC indicated a potent invasion front, and the SCC compartment was genetically unique, because the area has a higher frequency of mutation KRAS. The invasive tumors with distinct histological appearances shared the form of noninvasive IPMN as a common precursor, rather than de novo cancer, suggesting the significance of a genetic profiling scheme of tumors associated with IPMN.