47 research outputs found
Catheter-related bacteremia due to Kocuria rosea in a patient undergoing peripheral blood stem cell transplantation
BACKGROUND: Micrococcus species may cause intracranial abscesses, meningitis, pneumonia, and septic arthritis in immunosuppressed or immunocompetent hosts. In addition, strains identified as Micrococcus spp. have been reported recently in infections associated with indwelling intravenous lines, continuous ambulatory peritoneal dialysis fluids, ventricular shunts and prosthetic valves. CASE PRESENTATION: We report on the first case of a catheter-related bacteremia caused by Kocuria rosea, a gram-positive microorganism belonging to the family Micrococcaceae, in a 39-year-old man undergoing peripheral blood stem cell transplantation due to relapsed Hodgkin disease. This uncommon pathogen may cause opportunistic infections in immunocompromised patients. CONCLUSIONS: This report presents a case of Kocuria rosea catheter related bacteremia after stem cell transplantation successfully treated with vancomycin and by catheter removal
Biofilms of non-Candida albicans Candida species : quantification, structure and matrix composition
Most cases of candidiasis have been attributed to C. albicans, but recently, non-
Candida albicans Candida (NCAC) species have been identified as common
pathogens. The ability of Candida species to form biofilms has important clinical
repercussions due to their increased resistance to antifungal therapy and the ability
of yeast cells within the biofilms to withstand host immune defenses. Given this
clinical importance of the biofilm growth form, the aim of this study was
to characterize biofilms produced by three NCAC species, namely C. parapsilosis,
C. tropicalis and C. glabrata. The biofilm forming ability of clinical isolates of
C. parapsilosis, C. tropicalis and C. glabrata recovered from different sources, was
evaluated by crystal violet staining. The structure and morphological characteristics
of the biofilms were also assessed by scanning electron microscopy and the
biofilm matrix composition analyzed for protein and carbohydrate content. All
NCAC species were able to form biofilms although these were less extensive for
C. glabrata compared with C. parapsilosis and C. tropicalis. It was evident that C.
parapsilosis biofilm production was highly strain dependent, a feature not evident
with C. glabrata and C. tropicalis. Scanning electron microscopy revealed structural
differences for biofilms with respect to cell morphology and spatial arrangement.
Candida parapsilosis biofilm matrices had large amounts of carbohydrate with less
protein. Conversely, matrices extracted from C. tropicalis biofilms had low
amounts of carbohydrate and protein. Interestingly, C. glabrata biofilm matrix
was high in both protein and carbohydrate content. The present work demonstrates
that biofilm forming ability, structure and matrix composition are highly
species dependent with additional strain variability occurring with C. parapsilosis.Fundação para a Ciência e a Tecnologia (FCT) - SFRH/BD/28341/2006, PDTC/BIO/61112/200
Comparative radiological features of disseminated disease due to Mycobacterium tuberculosis vs non-tuberculosis mycobacteria among AIDS patients in Brazil
Background: Disseminated mycobacterial disease is an important cause of morbidity and mortality in patients with HIV-infection. Nonspecific clinical presentation makes the diagnosis difficult and sometimes neglected. Methods: We conducted a retrospective cohort study to compare the presentation of disseminated Mycobacterial tuberculosis (MTB) and non-tuberculous Mycobacterial (NTM) disease in HIV-positive patients from 1996 to 2006 in Brazil. Results: Tuberculosis (TB) was diagnosed in 65 patients (67.7%) and NTM in 31 (32.3%) patients. Patients with NTM had lower CD4 T cells counts (median 13.0 cells/mm3 versus 42.0 cells/mm3, P = 0.002). Patients with tuberculosis had significantly more positive acid-fast smears (48.0% vs 13.6%, P = 0.01). On chest X-ray, miliary infiltrate was only seen in patients with MTB (28.1% vs. 0.0%, P = 0.01). Pleural effusion was more common in patients with MTB (45.6% vs. 13.0%, P = 0.01). Abdominal adenopathy (73.1% vs. 33.3%, P = 0.003) and splenic hypoechoic nodules (38.5% vs. 0.0%, P = 0.002) were more common in patients with TB. Conclusion: Miliary pulmonary pattern on X-ray, pleural effusion, abdominal adenopathy, and splenic hypoechoic nodules were imaging findings associated with the diagnosis of tuberculosis in HIV-infected patients. Recognition of these imaging features will help to distinguish TB from NTM in AIDS patients with fever of unknown origin due to disseminated mycobacterial disease