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Corynebacterium striatum occasionally causes nosocomial infections, such as catheter-related bloodstream infection and pneumonia; however, C. striatum- related infective endocarditis or septic arthritis is uncommon. We present the case of an 85-year-old woman with infective endocarditis at the native valve and septic arthritis at the native shoulder joint caused by C. striatum. The patient was admitted for a 10-day history of fever and right shoulder pain. She had no history of artificial device implantation, injury, arthrocentesis, or hospitalization. A physical examination revealed conjunctival petechiae, a systolic heart murmur, and right shoulder joint swelling. C. striatum was observed in two blood culture sets. Transesophageal echocardiography revealed vegetation in the right aortic coronary cusp. Arthrocentesis at the right shoulder aspirated pyogenic fluid and C. striatum was detected in the culture. The patient was diagnosed with infective endocarditis and septic arthritis caused by C. striatum, and ampicillin was administered based on antimicrobial susceptibility test results. The patient's condition was initially stable; however, she developed pulmonary congestion on day 56 and eventually died. An autopsy demonstrated perforation of the aortic left coronary cusp with vegetation. C. striatum may cause native valve endocarditis and native joint septic arthritis. [ABSTRACT FROM AUTHOR]

• Ceftriaxone can cause encephalopathy in patients with end-stage renal disease. • Ceftriaxone-associated encephalopathy (CAE) can develop even at a dose of 1 g/day. • A high blood and cerebrospinal fluid ceftriaxone level may be CAE-related. • Estimation of ceftriaxone level may contribute to an accurate diagnosis. Neurotoxicity is a rare and intolerable adverse effect of ceftriaxone therapy. In most cases, it has been diagnosed on the basis of medical history rather than quantitative blood and cerebrospinal fluid testing. We report the case of a woman aged 78 years with ceftriaxone-associated encephalopathy. She regularly underwent hemodialysis. The patient received intravenous ceftriaxone at a dose of 1 g/day for 10 days for a urinary tract infection, and her consciousness level began to deteriorate during the therapy. Five days after ceftriaxone discontinuation, her symptoms rapidly improved. Thus, ceftriaxone-associated encephalopathy was suspected. Ceftriaxone levels in the blood and cerebrospinal fluid were high while the patient had disturbed consciousness. This case showed that ceftriaxone levels were related to ceftriaxone-associated encephalopathy. Therefore, the estimation of ceftriaxone levels may facilitate an accurate diagnosis. [ABSTRACT FROM AUTHOR]

Background The timing of surgical repair for ventricular septal perforation (VSP) is important because patients are susceptible to bleeding from fragile myocardial tissue or residual shunt during the acute phase of acute myocardial infarction (AMI). This study aimed to assess the results of delayed surgery for VSP performed 2 weeks after AMI. Methods In total, 24 consecutive postinfarction patients with VSP (mean age: 72.6 ± 10.4 years; 13 males) underwent operation between May 2003 and June 2016. We postponed surgery during the acute phase and performed an elective surgery if the patient could wait for 2 weeks with support from intra-aortic balloon pumping (IABP) and respiratory management. If we could not control heart failure and organ function worsened during that period, we performed emergency surgery. Postoperative outcomes included complications, 30-day mortality rate, long-term hospital death, reoperation rate, and risk factors for hospital mortality. We examined whether organ function was maintained by delaying the surgery. Results Of the 24 patients, 11 (45.8%) required emergency surgery, and 13 (54.2%) could wait 2 weeks for surgery. The average time from AMI onset to diagnosis of VSP was 4.5 ± 1.6 days, and the average time from VSP diagnosis to surgery was 9.0 ± 6.0 days; 5 patients (20.8%) required resurgery for VSP due to residual shunt, recurrent VSP, or pseudoaneurysm of the left ventricle. The 30-day mortality rate was 4.2% (1 patient), and long-term hospital mortality rate was 12.5% (3 patients). Organ function was maintained in 10 patients (76.9%) who underwent elective surgery, and organ dysfunction was not advanced by delaying the surgery. Conclusions We could delay surgery for an average of 9 days from VSP onset by means of IABP or respiratory management without the deterioration of organ function. The 30-day mortality and long-term outcome were favorable. [ABSTRACT FROM AUTHOR]

Infections occur more frequently in patients receiving biologics. However, cryptococcal infection is uncommon in patients receiving tocilizumab, an interleukin-6 inhibitor, in contrast to patients receiving tumor necrosis factor-α inhibitors. In this report, we describe a case of disseminated cryptococcosis in a 55-year-old man who was receiving tocilizumab every 2 weeks along with daily prednisolone and cyclosporine for Castleman's disease. He initially developed cellulitis on both upper limbs, and his condition worsened despite antibacterial therapy. Chest X-ray scanning and computed tomography demonstrated bilateral pulmonary infiltration. Cryptococcus neoformans was detected in blood, skin, and sputum cultures. He was diagnosed with disseminated cryptococcosis, and successfully treated with liposomal amphotericin B for a week followed by oral fluconazole for 11 months. The findings of this study indicate that cryptococcosis should be considered during the differential diagnosis of infection in patients receiving tocilizumab, especially in the presence of other risk factors for infections or a short tocilizumab dosing interval. [ABSTRACT FROM AUTHOR]

Salmonella enterica subsp. arizonae is a bacteria commonly found in the gut of reptiles. In humans, infections caused by this organism are rare. Most cases originate from southwestern United States, where rattlesnake products are often used in traditional medicine. In Asia, only a few cases have been described. This case report documents a case involving a 64-year-old woman with pyelonephritis caused by S. arizonae in Japan. She had no history of contact with reptiles or foreign travel. The likely route of transmission is unclear. She was treated with cephalosporins for 14 days and the pyelonephritis appeared to be resolved; however recurrence occurred twice –after two weeks and then after one month. Prolonged antibiotic therapy with amoxicillin resolved the infection. This case demonstrates that pyelonephritis associated with S. arizonae can be found outside of the typical geographic region and may not be associated with typical animal hosts. [ABSTRACT FROM AUTHOR]

Mobile-bearing total knee arthroplasty (TKA) expects high conformity and low contact stress. It is designed to correct the rotational mismatch between femoral and tibial components. We examined the difference in weight-bearing knee kinematics in patients with mobile-bearing and fixed-bearing TKA performing step-up activities. We randomly assigned 40 knees (37 patients) to mobile-bearing TKA (n=20) or fixed-bearing TKA (n=20). Using fluoroscopic imaging we evaluated knee kinematics during step-up activity one year after surgery. The total extent of rotation was not different for the two TKAs. Due to the axial rotation of the polyethylene insert, patients with mobile-bearing TKA had a wider range of absolute axial rotation. The position of the medial and the lateral condyles was significantly more posterior in the fixed-bearing TKA. There were only minor kinematic differences between the two TKAs. The polyethylene insert in the mobile-bearing TKA moved as designed especially with respect to the self-alignment feature. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To study the effects of aging and cartilage degeneration of the proximal tibiofibular- and femorotibial joint (PTFJ, FTJ) on the cartilage of the PTFJ using T 1 ρ and T 2 mapping. Materials and methods: We performed sagittal T 1 ρ and T 2 mapping of the PTFJ and FTJ on 55 subjects with knee disorders. We placed 3 regions of interest (ROIs) on images of the cartilage in the PTFJ, medial femoral condyle (MFC), and medial tibia plateau (MTP). Correlation analysis was performed for the T 1 ρ and T 2 values of each ROI and the patient age and the osteoarthritic grade of the PTFJ and FTJ. Results: The T 1 ρ and T 2 values of the PTFJ were affected neither by aging nor the osteoarthritic grade of the FTJ. Values of the FTJ normalized to PTFJ values were correlated with the osteoarthritic grade of the FTJ in the MFC (r =0.851 and 0.779, respectively) and the MTP (r =0.635 and 0.762, respectively). There was a significant difference in the T 1 ρ but not the T 2 value of the PTFJ and MFC between normal and mildly osteoarthritic cartilage of each joint. Conclusion: We document that the T 1 ρ and T 2 values of PTFJ cartilage were not affected by aging or cartilage degeneration in the FTJ. The T 1 ρ value of the PTFJ may represent a useful internal standard reference for evaluating early degeneration of the FTJ. [Copyright &y& Elsevier]

Capnocytophaga canimorsus is part of normal gingival flora of dogs and cats. The organism can cause septicemia, meningitis, and endocarditis in humans after contact with dogs or cats. In spite of the frequency of gastrointestinal symptoms in C . canimorsus infection patients, specific gastrointestinal disease or clinical images have not been reported. We report a case of C . canimorsus bacteremia presenting with acute cholecystitis in elderly woman. She suffered from general fatigue and right upper abdominal pain. She had leukocytosis and abnormal liver function tests. She showed abnormal findings of the gallbladder by abdominal computed tomography and ultrasonography. She was diagnosed with acute cholecystitis without gallstones and was administered with antibiotics. C. canimorsus was isolated from blood cultures. A history of an insignificant wound secondary to a dog bite was elicited. She recovered completely with antibiotic treatment. This case revealed that C. canimorsus bacteremia can be presented with acute cholecystitis, suggesting that C. canimorsus could cause cholecystitis. And this cholecystitis can be treated with antibiotics without operation. Physicians seeing patients with acute cholecysitis should ask questions regarding animal contact. [ABSTRACT FROM AUTHOR]

Idiopathic CD4 lymphocytopenia (ICL) is a rare disease characterized by marked loss of CD4 T-cells without human immunodeficiency virus infection. CD4 T-cells play an important role in granuloma formation in cryptococcal infection. Thus far, among ICL patients, it has not been concluded definitely whether granuloma is formed or not. We report the case of a 39-year-old woman with ICL and disseminated cryptococcal infection with granuloma formation. She was referred to our department because of a lung mass, osteolytic lesion, and a subcutaneous mass identified on a computed tomography scan, and an elevated C-reactive protein level. Cryptococcus neoformans was isolated from the tissues. She also had marked CD4 lymphocytopenia (33 cells/μL), without human immunodeficiency virus infection. In a biopsy specimen of the lung mass, granulomas containing CD4 T-cells were observed. The cryptococcosis was treated with liposomal amphotericin B followed by fluconazole and she was found to be cured. The CD4 T-cell count was persistently low. This case showed that granulomas containing CD4 T-cells can be formed in ICL patients with cryptococcal infection despite very low CD4 T-cell counts. [ABSTRACT FROM AUTHOR]

Listeria monocytogenes sometimes causes central nervous system infections. However, rhombencephalitis is a rare form of L. monocytogenes infection. Its clinical symptoms and magnetic resonance imaging (MRI) findings are often similar to those of vertebrobasilar stroke. We present the case of a 79-year-old woman with Listeria rhombencephalitis presenting with rhinorrhea and productive cough. She had giant cell arteritis (GCA) treated with prednisolone and methotrexate. She was admitted for loss of appetite, rhinorrhea, and productive cough. These symptoms were alleviated without specific treatment; however, she suddenly developed multiple cranial nerve palsies, and MRI showed hyperintense signals on diffusion-weighted imaging and hypointense signals on apparent diffusion coefficient in the brainstem. Ischemic stroke due to exacerbation of GCA was suspected, and treatment with intravenous methylprednisolone was initiated; however, seizures occurred, and a lumbar puncture was performed. Cerebrospinal fluid and blood cultures revealed L. monocytogenes , and she was diagnosed with Listeria rhombencephalitis. Although antibiotic treatment was continued, the patient died. Thus, when patients with rhinorrhea or productive cough develop sudden cranial nerve palsy, Listeria rhombencephalitis should be considered as a differential diagnosis, and lumbar puncture should be performed. [ABSTRACT FROM AUTHOR]

The emergence of the Alpha variant of novel coronavirus 2019 (SARS-CoV-2) is a concerning issue but their clinical implications have not been investigated fully. We conducted a nested case-control study to compare severity and mortality caused by the Alpha variant (B.1.1.7) with the one caused by the wild type as a control from December 2020 to March 2021, using whole-genome sequencing. 28-day mortality and other clinically important outcomes were evaluated. Infections caused by the Alpha variant were associated with an increase in the use of oxygen (43.4% vs 26.3%. p = 0.017), high flow nasal cannula (21.2% vs 4.0%, p = 0.0007), mechanical ventilation (16.2% vs 6.1%, p = 0.049), ICU care (30.3% vs 14.1%, p = 0.01) and the length of hospital stay (17 vs 10 days, p = 0.031). More patients with the Alpha variant received medications such as dexamethasone. However, the duration of each modality did not differ between the 2 groups. Likewise, there was no difference in 28-day mortality between the 2 groups (12% vs 8%, p = 0.48), even after multiple sensitivity analyses, including propensity score analysis. The Alpha variant was associated with a severe form of COVID-19, compared with the non-Alpha wild type, but might not be associated with higher mortality. [ABSTRACT FROM AUTHOR]

Skeletal tuberculosis (TB) accounts for a small percentage of all cases of TB. It is often difficult to diagnose, especially in the hip joint. TB arthritis can be masked by superinfection with other pathogens, leading to a delay in diagnosis and treatment. Trauma or surgery is a reported risk factor of TB arthritis. In contrast, descriptions of TB arthritis after a closed bone fracture are rare. We herein report a case involving an 81-year-old woman with septic arthritis superinfected with methicillin-resistant Staphylococcus aureus (MRSA) and Mycobacterium tuberculosis . Three months before presentation, she sustained a bone fracture of the left femur and was treated conservatively without surgery. She developed a fever at another hospital and was transferred to our institution. Computed tomography revealed the presence of abnormal fluid around the left hip joint. MRSA was detected from the fluid and blood cultures. The patient was diagnosed with MRSA arthritis and treated with antibiotics and surgical drainage. However, her fever persisted, and the abscess further developed and enlarged around the left hip. It was punctured and cultured again. Three weeks later, Mycobacterium tuberculosis was identified from the abscess culture. The septic arthritis was confirmed to have been caused by MRSA and M . tuberculosis . After the initiation of antituberculosis therapy, her fever subsided and the treatment was continued. This case demonstrates that the diagnosis of TB arthritis can be hindered by the existence of other pathogens and that TB arthritis can occur at a closed fracture site in the hip joint. [ABSTRACT FROM AUTHOR]

Campylobacter jejuni and Campylobacter coli are the leading causes of bacterial intestinal infections worldwide, while Campylobacter fetus subsp. fetus (C. fetus) has been reported to cause extraintestinal infections, including medical device implant infections. However, breast implant infections have rarely been reported. We describe the case of a 64-year-old woman with breast implant infection and vertebral osteomyelitis due to C. fetus. The patient recovered by surgical removal of the infected left implant and was treated with antibiotics for 6 weeks. However, two weeks after the completion of antibiotics, she experienced an infection in the right implant due to C. fetus , which had developed quinolone resistance with a G91T mutation during the treatment course. This case showed that C. fetus can cause breast implant infections, and although the infection may appear to be unilateral initially, the possibility of sequential contralateral infection should be considered. [ABSTRACT FROM AUTHOR]

Necrotizing fasciitis is a rapidly progressing bacterial infection of the superficial fascia and subcutaneous tissue that is associated with a high mortality rate and is caused by a single species of bacteria or polymicrobial organisms. Escherichia coli is rarely isolated from patients with monomicrobial disease. Further, there are few reports of extended-spectrum beta-lactamase (ESBL)-producing E. coli associated with necrotizing fasciitis. We report here our treatment of an 85-year-old man who was admitted because of necrotizing fasciitis of his right thigh. Streptococcus equisimilis was detected as a monomicrobial pathogen, and the infection was cured by amputation of the patient's right leg and the administration of antibiotics. However, 5 days after discontinuing antibiotic therapy, he developed necrotizing fasciitis on his right upper limb and died. ESBL-producing E. coli was the only bacterial species isolated from blood and skin cultures. This case demonstrates that ESBL-producing E. coli can cause monomicrobial necrotizing fasciitis, particularly during hospitalization and that a different bacterial species can cause disease shortly after a previous episode. [ABSTRACT FROM AUTHOR]

• Adenosine deaminase (ADA) in the cerebrospinal fluid (CSF) is not specific for diagnosing tuberculous meningitis in HIV infected patients. • Retroviral rebound syndrome can cause meningitis and can also cause ADA elevation in the CSF. • We have to be aware of retroviral rebound syndrome as a cause of ADA elevation in CSF, to avoid unnecessary anti-tuberculous treatment. Adenosine deaminase (ADA) in cerebrospinal fluid (CSF) is considered to be a useful biomarker in differentiating tuberculous meningitis (TBM) from other meningitis in non-HIV patients. However, its specificity decreases in patients with HIV, and other diseases such as cytomegalovirus encephalitis, toxoplasmosis or meningeal lymphomatosis can also elevate ADA in CSF. We here report a rare case of retroviral rebound syndrome in a HIV patient, whose ADA in CSF was elevated. [ABSTRACT FROM AUTHOR]

Platelets store self. agonists such as ADP and serotonin in dense core granules. Although exocytosis of these granules is crucial for hemostasis and thrombosis, the underlying mechanism is not fully understood. Here, we show that incubation of permeabilized platelets with unprenylated active mutant Rab27A-Q78L, wild type Rab27A, and Rab27B inhibited the secretion, whereas inactive mutant Rab27A-T23N and other GTPases had no effects. Furthermore, we affinity-purified a GTPRab27A-binding protein in platelets and identified it as Munc13-4, a homologue of Munc13-1 known as a priming factor for neurotransmitter release. Recombinant Munc13-4 directly bound to GTP-Rab27A and -Rab27B in vitro, but not other GTPases, and enhanced secretion in an in vitro assay. The inhibition of secretion by unprenylated Rab27A was rescued by the addition of Munc13-4, suggesting that Munc13-4 mediates the function of GTP-Rab27. Thus, Rab27 regulates the dense core granule secretion in platelets by employing its binding protein, Munc13-4. [ABSTRACT FROM AUTHOR]

Platelets play critical roles in hemostasis and thrombosis through their aggregation following activation of integrin α[sub IIb]β[sub 3]. However, the molecular mechanism of the integrin activation inside platelets remains largely unknown. Pharmacological experiments have demonstrated that protein kinase C (PKC) plays an important role in platelet aggregation. Because PKC inhibitors can have multiple substrates and given that non-PKC-phorbol ester-binding signaling molecules have been demonstrated to play important roles, the precise involvement of PKC in cellular functions requires re-evaluation. Here, we have established an assay for analyzing the Ca[sup 2+]-induced aggregation of permeabilized platelets. The aggregation of platelets was inhibited by the addition of the arginine-glycine-aspartate-serine peptide, an integrin-binding peptide inhibitor of α[sub IIb]β[sub 3], suggesting that the aggregation was mediated by the integrin. The aggregation was also dependent on exogenous ATP and platelet cytosol, indicating the existence of essential cytosolic factors required for the aggregation. To examine the role of PKC in the aggregation assay, we immunodepleted PKCα and β from the cytosol. The PKC-depleted cytosol lost the aggregation-supporting activity, which was recovered by the addition of purified PKCα. Furthermore, the addition of purified PKCα in the absence of cytosol did not support the aggregation, whereas the cytosol containing less PKC supported it efficiently, suggesting that additional factors besides PKC would also be required. Thus, we directly demonstrated that PKCα is involved in the regulation of Ca[sup 2+]-induced platelet aggregation. [ABSTRACT FROM AUTHOR]