Infections in non-myeloablative hematopoietic stem cell transplantation patients with lymphoid malignancies: spectrum of infections, predictors of outcome and proposed guidelines for fungal infection prevention.

The overall risk of infections is lower in patients undergoing non-myeloablative allogeneic stem cell transplantation (NST) than in conventional stem cell transplant recipients. We sought to evaluate conditions associated with increased risk of infections after NST. In 81 patients, 187 infection episodes were noted; chronic lymphocytic leukemia (138 episodes/100 person-years) and recipients of matched unrelated donor graft (128 episodes/100 person-years) had higher risk of infection. Only half of the cytomegalovirus (CMV) infections occurred 31-100 days after transplantation. Most patients with CMV infection were non-neutropenic (100%), had lymphoma (76%), were younger (<55 years; 72%) and had received matched related donor (MRD) graft (72%). However, graft-versus-host disease (GVHD) was present in only 15% of these patients. Seven (78%) of nine invasive fungal infections (IFI) were diagnosed >100 days after NST and were associated with high mortality (78%). Most patients with IFI were also not neutropenic (100%), had received MRD graft (100%), had lymphoma (78%) and were given systemic steroids (78%); unlike CMV infection, 67% of these patients also had GVHD. On the basis of our results, we propose that NST recipients with lymphoma treated with high-dose corticosteroids for GVHD be considered for antifungal prophylaxis or pre-emptive antifungal therapy.

Inhaled aminoglycosides in cancer patients with ventilator-associated Gram-negative bacterial pneumonia: safety and feasibility in the era of escalating drug resistance.

We sought to evaluate the safety and feasibility of inhaled aminoglycosides or colistin in cancer patients with ventilator-associated pneumonia (VAP) due to Gram-negative bacteria (GNB). A retrospective case-matched study was obtained after obtaining IRB approval in patients at the intensive care unit at our NCI-designated comprehensive cancer center between 1999 and 2005. Sixteen patients with GNB-VAP who received inhaled aminoglycosides or colistin were compared with 16 patients who had received these antibiotics intravenously alone. Eligible patients were required to have received at least six doses of inhaled therapy, or 3 or more days of intravenous therapy. Clinical Pulmonary Infection Scores were used to assess pneumonia severity. Standard ATS criteria were used to define VAP. Patients treated with inhaled antibiotics were less likely to have received corticosteroids (13% vs 50%; P < 0.02) and had a higher median baseline creatinine level (0.85 vs 0.6 mg/dL; P < 0.02) than patients treated intravenously. Pseudomonas aeruginosa (69%) was the most common cause of VAP. There were no serious adverse events associated with inhaled antibiotics. Patients who received these antibiotics intravenously developed renal dysfunction (31%); none of the patients treated with inhaled antibiotics developed nephrotoxicity (P < or = 0.04). Patients treated with inhaled antibiotics were more likely to have complete resolution of clinical (81% vs 31% in the intravenous antibiotic group; P < 0.01) and microbiologic infection (77% vs 8% in the intravenous antibiotic group: P < 0.0006). In a multivariate analysis adjusted for corticosteroid use, inhaled antibiotic therapy was predictive of complete clinical resolution (odds ratio [OR], 6.3; 95% confidence interval [CI], 1.1, 37.6; P < 0.04) and eradication of causative organisms (OR 36.7; 95% CI, 3.3, 412.2; P < 0.003). In critically ill cancer patients with Gram-negative VAP, inhaled aminoglycosides were tolerated without serious toxicity and may lead to improved outcome.

Changing trends in etiology of bacteremia in patients with cancer.

The present study was conducted to determine trends in the quantitative bacterial load patterns of bacterial bloodstream infections (BSI) caused by various bacteria in patients receiving care at a comprehensive cancer center. Bacterial loads of all consecutive quantitative blood cultures performed during 1998 and 2004 were graded quantitatively. Gram-positive bacteria (GPB) were responsible for the majority of BSI episodes in both years studied: 740 of 1,055 (73%) in 1998 and 820 of 1,025 (82%) in 2004. Compared with GPB infections, a significant proportion of infections caused by Gram-negative bacteria was associated with a high bacterial load (HBL) (11 vs 28% in 1998 and 10 vs 30% in 2004; p<0.001). In 2004, BSI episodes due to non-Pseudomonas non-fermentative GNB (Stenotrophomonas maltophilia and Acinetobacter spp) were significantly associated with a HBL compared to BSI due to Pseudomonas aeruginosa (47 vs 23%; p<0.05); this was not the case in 1998. Conversely, the HBLs commonly associated with BSI due to Staphylococcus aureus (50%) and Streptococcus spp (35%) versus coagulase-negative staphylococci (13%; p<0.0001) during 1998 were not noted during 2004 (22% Staphylococcus aureus, 20% Streptococcus spp, 21% coagulase-negative staphylococci; p>0.5). The spectrum of BSI continues to change and its prognostic implications in cancer patients needs further study.

Vigilancia epidemiológica de virus sincicial respiratorio (VSR) y adenovirus en un centro de atención cerrada para desnutridos severos / RSV and adenovirus surveillance in a center for infants with severe malnutrition

Con el objeto de evaluar la influencia de la desnutrición en la severidad de la infección respiratoria aguda (IRA) se efectuó una vigilancia epidemiológica de adenovirus y VRS en un Centro de Recuperación de desnutridos (CREDES) y en un hospital pediátrico de Santiago. Entre junio y agosto de 1992 se tomaron muestras de aspirado nasofaringeo al ingreso a 259 lactantes con infección respiratoria aguda baja en el hospital R. del Río; iguales muestras se obtuvieron 2 veces por semana de 14 lactantes desnutridos severos, durante toda su estadía en CREDES. Se hizo inmunofluorescencia indirecta para ADV y VRS. En los desnutridos los exámenes fueron persistentemente negativos, mientras que en el hospital pediátrico se detectaron VRS (47 por ciento) y ADV (54,4 por ciento). Se concluye que la desnutrición severa no sería de por si un factor favorecedor de la infección viral por VRS