Use of tigecycline for the management of Clostridium difficile colitis in oncology patients and case series of breakthrough infections.

BACKGROUND: Clostridium difficile infection (CDI) is the most frequent cause of nosocomial diarrhoea in adults. Cancer patients, in particular, are at a higher risk for CDI. Limited clinical data exist regarding the use of tigecycline for the treatment of CDI, especially in patients with oncologic and haematologic malignancies. AIM: To characterize the use of tigecycline for treatment of CDI in oncology patients at an academic cancer centre. METHODS: This was a retrospective, single-centre, single-arm, chart review evaluating the use of tigecycline for the management of CDI in oncology patients at an academic cancer centre. FINDINGS: The median age of CDI diagnosis in this patient group (N=66) was 65 years (range: 16-84) and the majority of patients had solid tumour malignancies. Fifty-six percent of patients had severe CDI, 70.3% of which were classified as having severe complicated disease. The median time to initiation of tigecycline therapy was 2 days (mean: 3.83) and the median number of tigecycline doses was 13 (range: 1-50). Twelve non-CDI breakthrough infections were observed, and four patients developed CDI while receiving tigecycline for non-CDI indications. The rate of death was 18% and the recurrence rate was 15.2%. CONCLUSION: Tigecycline did not lead to overt benefits in outcomes of oncology patients with CDI when compared to historical data. In addition, several breakthrough CDIs were observed in patients who received the drug for a non-CDI indication. Further prospective research is needed to validate the use of tigecycline for management of CDI.

A Case of Refractory Pulmonary Coccidioidomycosis Successfully Treated with Posaconazole Therapy.

Coccidioidomycosis is an endemic fungal infection caused by the inhalation of the spores of Coccidioides species. Patients with underlying immunosuppressive illness can contract chronic or disseminated disease which requires prolonged systemic therapy. Pulmonary coccidioidomycosis remains as an illusory and abstruse disease, with increased prevalence that poses as a challenge for clinicians in developing an effective strategy for treatment. Here, we report successful treatment of a refractory case of chronic relapsing pulmonary coccidioidomycosis in a 50-year old woman with a thin-walled cavitary lung lesion who was ultimately treated with posaconazole.

Current treatments for infection in neutropenic patients with hematologic malignancy.

Neutropenic patients with cancer are a heterogeneous group of patients who carry a variable risk for infection. When such patients present with fever, appropriate empiric antibiotic therapy is initiated and continued until clinical improvement or clinical or microbiologic data direct a modification in treatment. As the duration of neutropenia increases, so does the need for antimicrobial modifications. Changes in therapy may include antimicrobials directed against gram-positive bacteria, resistant gram-negative bacteria, or fungi. Because of the high risk for colonization by vancomycin-resistant enterococci, vancomycin use is restricted as first-line empiric therapy unless the patient is at a high risk for serious gram-positive infection. Usually in the setting of neutropenia, gram-positive infections are of low virulence. Prophylactic antibiotic therapy may increase the selection of resistant strains and should be avoided. Antibiotic therapy should always be combined with prudent infection-control measures, such as aseptic practices, barrier isolation, handwashing, removal of infected catheters, and infection monitoring. In the immunocompromised patient with cancer and neutropenia, all infections should be treated, with the extent, duration, and site of treatment being directed by risk stratification and specific pathogen identification. Patients with neutropenia are at risk for severe morbidity and mortality related to infection.

New directions in antimicrobial therapy.

The virulent microorganisms that we try to contain with new antimicrobial agents quickly find the gap in our defenses and exploit it. Resistance to all available antibiotics at the same time, however, rarely occurs. The authors report the most current antimicrobials used as monotherapy or in combination to successfully treat the more resistant pathogens. The higher mortality and subsequent cost to treat these infections are reviewed.

The detection of airborne Mycobacterium tuberculosis using micropore membrane air sampling and polymerase chain reaction.

STUDY OBJECTIVES: Mycobacterium tuberculosis (MTb) bacilli are carried on airborne droplet nuclei produced by aerosolization that can occur from coughing, talking, or even singing. Because of their prolonged period of suspension, they can be filtered from the air onto a porous medium and readily detected using polymerase chain reaction (PCR). DESIGN: Prospective cohort analysis. SETTING: Samples of circulating air were collected over a 12-month period from within the rooms of 10 hospitalized patients who were under respiratory isolation to rule out MTb infection. A small laboratory pump was used to draw ambient air at a rate of 2 L/min over a 6-h period through a 0.2-microm polycarbonate membrane filter placed near the patient's bed. Analysis of the membrane filters was conducted using PCR. Sputum cultures for MTb were performed simultaneously, and the results of smears stained for acid-fast bacilli (AFB) were noted. MEASUREMENTS AND RESULTS: MTb complex was successfully detected by PCR in six of seven patients in whom sputum MTb cultures were subsequently positive, and in zero of three with subsequently negative sputum cultures. Sampling in one patient with a positive culture, in whom PCR results were negative, was only carried out for 2 h due to pump malfunction. One of the six PCR-positive patients was AFB-smear negative at the time of air sampling. CONCLUSIONS: Our preliminary findings indicate that the technique of Micropore membrane air sampling with PCR analysis has important applications in the epidemiology and diagnosis of MTb.

Women at risk: papanicolaou smear screening in Florida.

In the South, especially Appalachia, the incidence of invasive cervical cancer has remained high relative to the rest of the United States. Populous Florida now stands third among states by incidence and fifth from last in Pap screening. During the 1994 survey, 2,059 Florida women chosen as a multi-stage cluster sample were interviewed concerning their use of screening Pap smears. Never-participation in screening percentages were significantly higher in Hispanic women (14.7%), those sharing household incomes of less than $10,000 (13.2%), and women limited to a high school education (10.7%), but not among respondents older than 64 years of age (8.7%). Despite continued annual physician contact by most, yearly Pap smears fell to only 57.0% among women aged 55-64 years. It is important that physicians target these women and use any appropriate clinical contact to educate them about risk factors for cervical cancer while encouraging regular, continued use of this life-saving test.

Identification of an amphotericin B resistant strain of Candida albicans using a rapid 3H-glucose incorporation microassay.

Using a 3H-glucose incorporation assay, antifungal sensitivity testing undertaken on an isolate of Candida albicans cultured from the blood of a bone marrow transplant patient documented resistance to amphotericin B but sensitivity to fluconazole and itraconazole. Information obtained from in vitro antifungal sensitivity testing can be used to direct in vivo antifungal therapy. Widespread application of standardized in vitro antifungal sensitivity testing is needed.

Primary cutaneous aspergillosis: case report and review of the literature.

Primary cutaneous aspergillosis is an uncommon entity that may occur in immunosuppressed hosts, usually resulting from contact with contaminated medical devices used in patient care. The infection spreads locally with subsequent skin necrosis due to angioinvasion and thrombosis. We report primary cutaneous aspergillosis following contact with contaminated gauze, and we review the relevant literature.

Catheter-related complications of cancer therapy.

Although the management of CVC-related infection appears complex and at times the literature seems to be contradictory, simple guidelines can direct the clinician in a stepwise fashion. Knowledge of the pathogenesis of each organism and the immune status of the host is crucial to decide whether catheter removal or retention is indicated. For example, in general, GNB bacteremia does not immediately prompt catheter removal in a neutropenic patient but does in a nonneutropenic host because of the gastrointestinal source of the former and a primary catheter source in the latter. In summary, as more CVCs are inserted in patients undergoing chemotherapeutic, antimicrobial, transfusional, and nutritional supportive care, novel approaches to prevention and treatment of the associated infectious complications inherent with such devices are needed. A multifaceted approach from impregnated catheters to local catheter-site antisepsis was reviewed. We may find, however, that as simple handwashing between patients is crucial to infection control, so too is a trained catheter-care team using total barrier precautions and ensuring proper local catheter maintenance critical to preventing CVC-related infections.

The microbiology of colonization, including techniques for assessing and measuring colonization.

Organisms living on our external and internal body surfaces are the first contact for many potentially pathogenic invaders. Factors that alter this microenvironment include antibiotics, the host immunity, and the various diseases of man and their treatment. Predicting when colonization leads to infection remains an important challenge for every clinician. The maintenance and breakdown of colonization resistance by changes in the native microflora and the body's natural mucosal coating by various extrinsic and intrinsic factors is reviewed in this article. Quantitative culture methods developed to improve the predictive value of a given sampling technique (most notably with bronchoscopy) is presented. Besides improving diagnostic capabilities, quantitative cultures can be used successfully as an epidemiologic tool for some outbreak investigations.