Background Between August 1 and October 30, 1998 (outbreak period), an increased incidence of central venous catheter (CVC)-associated gram-negative bacterial bloodstream infection (GN-BSI) was detected in hematopoietic stem cell transplantation (HSCT) candidates and recipients in an outpatient HSCT unit. The objectives of the present study were to determine strategies for controlling the outbreak and identify risk factors for GN-BSI. Methods Two case-control studies, an assessment of infection control practices, microbiologic studies, and water quality analysis were conducted. A case was defined as any outpatient with a CVC and a primary GN-BSI during the outbreak period. Results All of the 31 case patients identified had needleless intravenous (IV) access devices. Independent risk factors for CVC-associated GN-BSI were self-administered IV infusion (odds ratio [OR] = 6.2; P = .02), lower frequency of needleless device changes (OR = 15.2; P = .03), and more frequent baths (OR = 1.4; P = .05). Interventions included increased frequency of needleless device change, recommending showers rather than baths, and use of CVC protection during showering/bathing. After these interventions, the CVC-associated GN-BSI rate declined to below the preoutbreak period rate (2.1/1000 vs 0.3/1000 CVC-days; P Conclusions This study demonstrated an increased risk of CVC-associated GN-BSIs related to self-IV infusion, bathing habits, and frequency of needleless device change. Infection control practices associated with the use of needleless devices may expose susceptible patients to increased risk for BSI.

Abstract Patients with neutropenia lasting for more than 10 d, who develop fever and pulmonary infiltrates, are at risk of treatment failure under conventional broad-spectrum antibacterial therapy. Filamentous fungi are predominant causes of failure, however, multi-resistant gram-negative rods such as Pseudomonas aeruginosa or Stenotrophomonas maltophilia may be involved. Prompt addition of mould-active systemic antifungal therapy, facilitated by early thoracic computed tomography, improves clinical outcome. Non-culture-based diagnostic procedures to detect circulating antigens such as galactomannan or 1,3-beta- d -glucan, or PCR techniques to amplify circulating fungal DNA from blood, bronchoalveolar lavage or tissue specimens, may facilitate the diagnosis of invasive pulmonary aspergillosis. CT-guided bronchoalveolar lavage is useful in order to identify causative microorganisms such as multidrug-resistant bacteria, filamentous fungi or Pneumocystis jiroveci . For pre-emptive antifungal treatment, voriconazole or liposomal amphotericin B is preferred. In patients given broad-spectrum azoles for antifungal prophylaxis, non-azole antifungals or antifungal combinations might become first choice in this setting. Antifungal treatment should be continued for at least 14  d before non-response and treatment modification are considered. Microbial isolates from blood cultures, bronchoalveolar lavage or respiratory secretions must be critically interpreted with respect to their aetiological relevance for pulmonary infiltrates.

Abstract Yeasts and filamentous fungi are beginning to emerge as significant microbial pathogens in patients with cystic fibrosis (CF), particularly in relation to allergic-type responses, as seen in patients with allergic bronchopulmonary aspergillosis (ABPA), Aspergillus bronchitis and in invasive fungal disease in lung transplant patients. Four fungal media were compared in this study, including Sabouraud Dextrose Agar (SDA) and Medium B, with and without the addition of selective antibiotics, where antibiotic-supplemented media were designated with + . These media were compared for their ability to suppress contaminating, mainly Gram−ve pathogens, in CF sputa ( Pseudomonas aeruginosa , Burkholderia cepacia complex [BCC] organisms) and to enhance the growth of fungi present in CF sputum. Medium B consisted of glucose (16.7 g/l), agar (20 g/l), yeast extract (30 g/l) and peptone (6.8 g/l) at pH 6.3 and both SDA + and Medium B + were supplemented with cotrimethoxazole, 128 mg/l; chloramphenicol, 50 mg/l; ceftazidime, 32 mg/l; colistin, 24 mg/l). Employment of SDA + or Medium B + allowed an increase in specificity in the detection of yeasts and moulds, by 42.8% and 39.3%, respectively, over SDA when used solely. SDA + had a greater ability than Medium B + to suppress bacterial growth from predominantly Gram−ve co-colonisers. This is a significant benefit when attempting to detect and isolate fungi from the sputum of CF patients, as it largely suppressed any bacterial growth, with the exception of the BCC organisms, thus allowing for an increased opportunity to detect target fungal organisms in sputum and represented a significant improvement over the commercial medium (SDA), which is currently used. Overall, both novel selective media were superior in their ability to suppress bacteria in comparison with the commercially available SDA medium, which is routinely employed in most clinical microbiology diagnostic laboratories presently. Alternatively, Medium B + had a great ability to grow fungi than SDA + and when employed together, the specificity of combined use was 82%, with a sensitivity for yeasts, filamentous fungi, and combined overall fungi of 96.0%, 92.3% and 96.0%, respectively. Overall, when employing one fungal selective medium for the routine detection of yeasts and filamentous fungi in the sputum of CF patients, we would recommend employment of Medium B + . However, we would recommend the combined employment of SDA + and Medium B + , in order to synergistically isolate and detect the greatest number of fungi present in CF sputa.