Successful control of an outbreak of GES-5 extended-spectrum ß-lactamase-producing Pseudomonas aeruginosa in a long-term care facility in Japan.

BACKGROUND: Little is known about multidrug-resistant Pseudomonas aeruginosa (MDRP) outbreaks in long-term care facilities (LTCFs). AIM: To describe an MDRP outbreak in an LTCF and to clarify risk factors for MDRP acquisition. METHODS: Patients who were positive for MDRP at an LTCF from January 2013 to January 2014 were analysed. A descriptive analysis, a case-control study, and a microbiological analysis were performed. FINDINGS: A total of 23 MDRP cases were identified, 16 of which were confirmed in sputum samples. Healthcare workers were observed violating hand hygiene procedures when performing oral, wound, and genital care. Nasogastric tube and oxygen mask use was associated with MDRP acquisition in the respiratory tract, which might have been confounded by poor hand hygiene. Sharing unhygienic devices, such as portable oral suction devices for oral care, and washing bottles and ointments for wound and genital care with inadequate disinfection could explain the transmission of MDRP in some cases. Isolates from 11 patients were found to be indistinguishable or closely related by pulsed-field gel electrophoresis and harbouring the blaGES-5 gene. Subsequent enhanced infection control measures were supported by nearby hospitals and a local public health centre. No additional cases were identified for a year after the last case occurred in January 2014. CONCLUSION: An outbreak of MDRP with an antimicrobial resistance gene, blaGES-5, occurred in a Japanese LTCF. It was successfully controlled by enhanced infection control measures, which neighbouring hospitals and a local public health centre supported.

Angiotensin II receptor blockade prevents microangiopathy and preserves diastolic function in the diabetic rat heart.

BACKGROUND: Cardiac microangiopathy may be involved in the development of heart failure in diabetes mellitus. OBJECTIVE: To evaluate the effect of angiotensin II receptor blockade on cardiac function and fine structures in diabetes. METHODS: Male Otsuka Long-Evans Tokushima Fatty (OLETF) rats (n = 30), a model of spontaneously developing diabetes mellitus, and their diabetes resistant counterparts (n = 20) were used. At 30 weeks of age, when the OLETF rats show hyperglycaemic obesity with hyperinsulinaemia, the animals were divided into two groups and given candesartan, an angiotensin II receptor blocker, 0.2 mg/kg/day, or vehicle for six weeks. Capillary density was evaluated in the left ventricular myocardium by electron microscopy, matrix metalloproteinase (MMP) activity by zymography, and cytokines by reverse transcriptase polymerase chain reaction. RESULTS: Compared with the control rats, the OLETF rats at 36 weeks showed decreased peak negative dP/dt (mean (SD): 2350 (250) v 3492 (286) mm Hg/s) and increased cardiomyocyte diameter (24.3 (0.6) v 18.9 (0.6) microm) (both p < 0.05). Thickening of the capillary basement membranes and decreased capillary density were observed. Angiotensin receptor blockade improved almost all the haemodynamic variables, and the histological findings became similar to those of the controls. Angiotensin receptor blockade also activated MMP-2 and prevented an increase of inflammatory cytokines, especially interleukin (IL)-1beta and IL-6, in the diabetic heart. CONCLUSIONS: Angiotensin II receptor blockade preserved left ventricular diastolic function. It was also potent at improving cardiomyocyte diameter and the thickening of the capillary basement membrane, increasing MMP-2 activity, and decreasing inflammatory cytokines. With all these changes, candesartan could contribute to cardioprotection in diabetes mellitus.

Enterovirus RNA replication in cases of dilated cardiomyopathy: light microscopic in situ hybridization and virological analyses of myocardial specimens obtained at partial left ventriculectomy.

OBJECTIVE: Recently, attention has been focused on enteroviral infection of the heart in the genesis of dilated cardiomyopathy (DCM). To determine the location of enteroviral RNA in the myocardium, we performed light microscopic in situ hybridization (ISH) and virological analyses of myocardial specimens obtained at partial left ventriculectomy (PLV). METHODS: Posterolateral walls of the left ventricle from 26 DCM patients were examined. Myocardial specimens were tested for the presence of enteroviral genomes by polymerase chain reaction (PCR). We selected two age-matched groups (10 patients each) in which enteroviruses were either present (EV-plus group) or not (EV-minus group). For both groups, we examined in situ localization of enteroviral RNA in the myocardium by ISH. RESULTS: In PCR studies, both sense and antisense enteroviral RNA were detected in the myocardium of seven patients in the EV-plus group. The presence of this RNA indicates active viral replication in the myocardium. Five of seven patients who exhibited both sense and antisense enteroviral RNA died early after surgery. On ISH, three patients had evidence of active replication of enteroviral genomes. Viral genomes were present in myocardial lesions, especially in endocardial sites. Viral signals were found in degenerating myocardial cells, interstitial inflammatory cells, and endothelial cells of small vessels. These positive signals were not detected in the myocardium of the EV-negative group. CONCLUSIONS: We detected both sense and antisense enteroviral RNA in various myocardial lesions. This suggests that active enteroviral replication plays a role in the development of myocardial lesions in DCM patients. Active viral replication appears to be a prognostic factor for DCM after PLV. Further study of active viral replication in myocardial lesions will provide information useful for evaluating different therapeutic strategies for DCM.

Evaluation of viral infection in the myocardium of patients with idiopathic dilated cardiomyopathy.

OBJECTIVES: The aim of this study was to evaluate the viral etiology of idiopathic dilated cardiomyopathy (DCM). BACKGROUND: The demonstration of enteroviral genome in hearts with DCM has reinforced the importance of enteroviruses in the pathogenesis of DCM. However, there is uncertainty about the character and activity of enteroviruses detected in the myocardium. Recently, the association of hepatitis C virus or adenovirus with DCM has been reported. METHODS: Myocardial specimens from 26 patients with idiopathic DCM, which were obtained at partial left ventriculectomy (PLV), were examined virologically. Strand-specific detection of enteroviral RNA was performed to differentiate active viral replication from latent persistence. Polymerase chain reaction was used to detect genomic sequences of hepatitis C virus, adenovirus, cytomegalovirus, influenza viruses, mumps virus, herpes simplex viruses, varicella-zoster virus and Epstein-Barr virus. RESULTS: Plus-strand enteroviral RNA was detected in 9 (35%) of the 26 patients. Minus-strand enteroviral RNA was determined in seven (78%) of these nine plus-strand RNA-positive patients. Sequence analysis revealed that the enteroviruses detected were coxsackie B viruses, such as coxsackievirus B3 and B4. However, genetic material from other viruses was not detected. Six (86%) of seven minus-strand enteroviral RNA-positive patients died of cardiac insufficiency within the first six months after PLV. CONCLUSIONS: Coxsackie B viruses were seen in hearts with idiopathic DCM. Active viral RNA replication appeared to be present in a significant proportion of these cases. Minus-strand coxsackieviral RNA in the myocardium can be a marker for poor clinical outcome after PLV. There was no evidence of persistent infection by other viruses in hearts with DCM.

Prosthetic ball valve endocarditis due to Gemella species.

A case is presented of endocarditis that was affecting a prosthetic ball valve (Starr-Edwards) and which was caused by Gemella species. A 57-year-old man was admitted with a 3-day history of abdominal pain with fever. At the time of admission, his temperature was 37.7 degrees C and laboratory tests showed elevated inflammatory parameters and an increased neutrophil count. However, transthoracic echocardiogram showed no vegetation. During hospitalization, Gemella spp. were detected by blood culture, and a transesophageal echocardiogram showed vegetation on the prosthetic valve. He was treated with intravenous ampicillin and astromycin, and also underwent valve replacement. This is the first case in Japan of infective endocarditis of a prosthetic valve due to Gemella spp.

Spontaneous myocarditis in DBA/2 mice. Light microscopic study with transmission and X-ray analytical electron microscopic studies.

DBA/2 inbred mice spontaneously develop myocarditis and a unique form of subepicardial inflammation of the right ventricle characterized by a prominent eosinophilic infiltrate with calcinosis. We studied this myocarditis using light microscopy and both transmission and analytical X-ray electron microscopy, paying particular attention to eosinophil-associated cardiocyte injury. At 5 weeks of age, many eosinophils and mononuclear cells (MNCs) were seen in the subepicardium of the right ventricle. Electron microscopy showed that cardiocytes underwent degenerative changes, including myofibrillar lysis, accumulation of Z-band material and mitochondrial inclusions, and rupture of plasma membranes. The infiltrating eosinophils appeared to be activated, and cells with cytoplasmic vacuoles, suggestive of degranulation, were noted. The myocardial injury was most severe in the 7th week and healed with myocardial fibrosis and calcinosis by the 8th week. Analytical X-ray electron microscopy showed that the calcinosis was initiated in mitochondrial inclusions of injured cardiocytes. The peripheral eosinophil count did not increase during the course of the disease, but there was a positive correlation between the ratio of eosinophils to infiltrated white blood cells (Eo/WBCs) in the right ventricle and the severity of myocardial damage. Eosinophils may play a significant part in subepicardial cardiocyte injury seen in DBA/2 mice.

[Clinicopathological features of influenza myocarditis and pericarditis].

Myocarditis is a rare complication of influenza infection but is occasionally fatal. Recent application of percutaneous cardiopulmonary support and/or intraaortic balloon pumping to the serious case of viral myocarditis brought an good prognosis. We should recognize that the patient with viral infection such as influenza may have myocarditis and should make an early diagnosis for adequate treatment in time. To avoid misdiagnosis we must know characteristic symptoms and signs of cardiac involvement during influenza infection.

Intracellular viral localization in murine coxsackievirus-B3 myocarditis. Ultrastructural study by electron microscopic in situ hybridization.

Group B Coxsackieviruses are a common cause of myocarditis. To detect the viral genome and its localization in the myocardium, we examined C3H/He mice with Coxsackievirus B3 (CVB3) myocarditis on days 5, 8, and 14 after inoculation by the reverse transcriptase polymerase chain reaction and by in situ hybridization. Sense and antisense CVB3 RNA were detected in the myocardium of all mice up to day 14 by reverse transcriptase polymerase chain reaction. Light microscopic in situ hybridization with a cDNA probe for CVB3 showed clusters of positive signals in the areas of myocardial necrosis and cell infiltration. With electron microscopic in situ hybridization, CVB3 RNA was detected in the cytoplasm of cardiocytes, between the myofibrils, near the mitochondria, and in tubular or vesicular structures. Viral RNA was also detected in necrotic debris, in the cytoplasm of macrophages, and in the cytoplasm of interstitial fibroblasts. These findings suggest that CVB3 RNA is replicated in the cytoplasm of cardiocytes, transferred into tubular or vesicular structures, released into the interstitium, and phagocytosed by macrophages. Some positive signals were also detected in the cytoplasm of cardiocytes showing close contact with infiltrating lymphocytes, suggesting that the lymphocytes recognized virus-infected cardiocytes and caused cell-mediated immune cardiocyte damage.

Genomic detection of enteroviruses in the myocardium--studies on animal hearts with coxsackievirus B3 myocarditis and endomyocardial biopsies from patients with myocarditis and dilated cardiomyopathy.

We examined myocardial tissues for the presence of enteroviral RNA in animal models with experimental coxsackievirus B3 myocarditis and in endomyocardial biopsy samples obtained from patients clinically diagnosed as having dilated cardiomyopathy or myocarditis using polymerase chain reaction (PCR) gene amplification with enterovirus-generic primers and/or coxsackievirus B3-specific primers. In animal models, coxsackievirus B3 was detected in myocardial tissues up to 28 days, 56 days and 180 days after inoculation, in C3H/He mice, A/J mice and Syrian golden hamsters, respectively. The viral genomes were identified by in situ hybridization in myocardial cells and some interstitial cells in and around the myocarditic lesions in animals. In human endomyocardial biopsy samples, enteroviral RNA sequences were detected in 8 (32%) out of 25 patients with clinical dilated cardiomyopathy and in 3 (33%) out of 9 patients with clinical myocarditis. The patients showing histologic findings of myocarditis and clinical features resembling dilated cardiomyopathy had a high incidence (83%) of positive PCR result for enteroviral RNA sequences. Additionally, 25% of patients with dilated cardiomyopathy showing no histologic findings of myocarditis had positive PCR result. This study supports a link between viral myocarditis and dilated cardiomyopathy.

Viral genomic detection in the hearts of C3H/He mice with experimental Coxsackievirus B3 myocarditis by gene amplification using the polymerase chain reaction.

On the basis of the detection of the enteroviral RNA in the hearts of patients with healed myocarditis and dilated cardiomyopathy, we investigated cardiac viral persistence in experimental myocarditis. Weanling C3H/He mice were given myocarditis by inoculation with coxsackievirus B3 (Nancy strain), and their hearts were examined by genomic studies and viral isolation up to the 180th day after inoculation. The virus was isolated from the heart until the 9th day. By slot-blot hybridization, viral RNA was also only detected until the 9th day in the heart. Specific DNA amplification using the polymerase chain reaction (PCR) was performed after a reverse transcriptase reaction, then followed by Southern blot hybridization with a 32P-labelled oligomer probe. This technique achieved the type-specific detection of coxsackievirus B3 even at a level of less than one of the 50% tissue culture infective dose (TCID50). With this technique, viral RNA was detected up to the 28th day after inoculation. Thus, the viral RNA persisted in the hearts of these mice even when infectious virus could no longer be detected.