John D. Christie

Atypical Cytomorphologic Appearance of Cryptococcus neoformans

BACKGROUND: Cryptococcus neoformans is not generally recognized as producing pseudohyphae. Although atypical morphologic forms have been described in the microbiology literature, we believe this is the first complete cytologic report describing this uncommon and unusual cytologic appearance of cryptococcal infection. CASES: In five cases of cryptococcal infection, C neoformans formed chains of budding yeasts, pseudohyphae and germ tube-like structures. The atypical forms of C neoformans were seen in cerebrospinal fluid, imprints and in histopathologic sections from multiple organs from two human immunodeficiency virus (HIV)-positive patients; in pleural fluid from a patient with non-Hodgkins lymphoma; in crush smears from a stereotactic biopsy of the brain; and in a fine needle aspirate of a lung nodule in two patients with no known risk factors for HIV infection. CONCLUSION: Recognition of atypical cytomorphologic variants of C neoformans is important since there are potential diagnostic pitfalls for confusing these atypical-appearing organisms with a Candida-type species or fungal contaminants. Special stains for capsular material and culture can be helpful in making a correct diagnosis.

Outbreak of Mycobacterium mucogenicum bloodstream infections among patients with sickle cell disease in an outpatient setting.

OBJECTIVE To study an outbreak of Mycobacterium mucogenicum bloodstream infections in an outpatient setting. DESIGN Outbreak investigation and retrospective chart review. SETTING University outpatient clinic. Patients. Patients whose blood cultures tested positive for M. mucogenicum in May or June 2008. METHODS An outbreak investigation and a review of infection control practices were conducted. During the process, environmental culture samples were obtained. Isolates from patients and the environment were genotyped with the DiversiLab typing system to identify the source. Chart reviews were conducted to study the management and outcomes of the patients. RESULTS Four patients with sickle cell disease and implanted ports followed in the same hematology outpatient clinic developed blood cultures positive for M. mucogenicum. A nurse in the clinic had prepared intravenous port flushes on the sink counter, using a saline bag that was hanging over the sink throughout the shift. None of the environmental cultures grew M. mucogenicum except for the tap water from 2 rooms, 1 of which had a faucet aerator. The 4 patient isolates and the tap water isolate from the room with the aerator were found to have greater than 98.5% similarity. The subcutaneous ports were removed, and patients cleared their infections after a course of antibiotic therapy. CONCLUSION The source of the M. mucogenicum bacteremia outbreak was identified by genotyping analysis as the clinic tap water supply. The preparation of intravenous medications near the sink was likely an important factor in transmission, along with the presence of a faucet aerator.

Intestinal spirochetes. Organisms in search of a disease

The field of gastroenterology includes many examples of organisms whose pathogenicity has been questioned in the past. Older members of the American Society for Clinical Pathology might remember the skepticism with which the original publications by Warren 1 and Marshall 2 detailing the description of Helicobacter pylori associated with chronic active gastritis were greeted. It was not until Kochs postulates were fulfilled by having a volunteer ingest the organism that the bacterium was accepted as a pathogen. 3 We now accept that H pylori, while present as an asymptomatic infection in many people, is a pathogen with a large variety of manifestations. On the other hand, the pathogenic status of Blastocystis hominis probably will never be resolved satisfactorily. In this issue of the Journal, Koteish and colleagues 4 present a retrospective review of 14 cases in which endo-scopic biopsies revealed the presence of spirochetes in the colon. The study raises many interesting questions about the clinical and pathogenic significance of these organisms but provides few definitive answers. Genotypic analysis of 13 of the cases indicated that 11 patients were infected with Brachyspira aalborgi, while the remaining 2 patients had Brachyspira pilosicoli infections. The predominance of B aalborgi as the intestinal spirochete was confirmed by a recent study from Australia with similar findings. 5 Six of the patients had symptoms, which was the reason for biopsy: 2 HIV-infected men and all 4 of the children. The remaining patients, who were all adults, were asymptomatic and underwent biopsy for reasons other than diarrhea or abdominal pain. Two patients were treated with antibiotics. The 1 patient for whom follow-up information was available had complete resolution of symptoms. Two of the asymptomatic adults had follow-up biopsy, with spirochetes found in the specimen from one of these patients. Interestingly, even in symptomatic patients, the presence of spirochetes, which were found throughout the colon, was not associated with active inflammation , mucosal damage, or histologic changes consistent with chronic infection. What are we to make of these findings? Because this case series involved a search of the surgical pathology files in a large tertiary care hospital from January 1994 to January 2002, the prevalence of intestinal spirochetosis, whether symptomatic or asymptomatic, may be low. However, Koteish and colleagues 4 reported that spirochetes are present in the colon in approximately 2.5% to 16% of people from Western countries, 6,7 with prevalence rates as high as 50% in …

“Stat” Multiplex Polymerase Chain Reaction

In the laboratory, the department most affected by the introduction of molecular diagnostic tools has been the clinical microbiology laboratory. For organisms such as Clostridium difficile , polymerase chain reaction (PCR) is the gold standard for diagnosis. Incorporation of molecular diagnostic techniques into microbiology laboratories of differing sizes has been hastened by the development of simplified technological methods, individual cassettes incorporating all reagents necessary for diagnosis, and instruments allowing multiple tests to be run at the same time. Companies, such as Cepheid (Sunnyvale, CA), with its GeneXpert technol ogy, even advertise that their tests can be run in a physician’s office. Pressure by the US Food and Drug Administration (FDA) on companies such as Roche has pushed them to change their offerings in molecular diagnosis from analyte-specific reagent kits to a commercially prepared, prepackaged assay with detailed instructions for performance of the test. This change has hastened adoption of molecular methods into the testing menu of laboratories that do not have the resources and staff to perform the extensive and time-consuming validations of assays that are not approved by the FDA. Molecular methods have probably found their greatest use in microbiology laboratories in the diagnosis of viral infections. The reasons for the movement to molecular methods in this arena are varied. The rapid assays for agents such as influenza A and B and respiratory syncytial virus …

Stat Multiplex Polymerase Chain Reaction Its Role in Clinical Microbiology

In the laboratory, the department most affected by the introduction of molecular diagnostic tools has been the clinical microbiology laboratory. For organisms such as Clostridium difficile , polymerase chain reaction (PCR) is the gold standard for diagnosis. Incorporation of molecular diagnostic techniques into microbiology laboratories of differing sizes has been hastened by the development of simplified technological methods, individual cassettes incorporating all reagents necessary for diagnosis, and instruments allowing multiple tests to be run at the same time. Companies, such as Cepheid (Sunnyvale, CA), with its GeneXpert technol ogy, even advertise that their tests can be run in a physician’s office. Pressure by the US Food and Drug Administration (FDA) on companies such as Roche has pushed them to change their offerings in molecular diagnosis from analyte-specific reagent kits to a commercially prepared, prepackaged assay with detailed instructions for performance of the test. This change has hastened adoption of molecular methods into the testing menu of laboratories that do not have the resources and staff to perform the extensive and time-consuming validations of assays that are not approved by the FDA. Molecular methods have probably found their greatest use in microbiology laboratories in the diagnosis of viral infections. The reasons for the movement to molecular methods in this arena are varied. The rapid assays for agents such as influenza A and B and respiratory syncytial virus …

151Is Nursing Home Specific Antibiogram Necessary for All Nursing Homes

151. Is Nursing Home Specific Antibiogram Necessary for All Nursing Homes? Kaushal Shah, MD; Paul Cook, MD; Tae Lee, MD; Muhammad Salman Ashraf, MD; John Christie, MD, PhD; Xiangming Fang, PhD; Infectious Disease, East Carolina University/ Vidant Medical Center, Greenville, NC; Infectious Diseases, East Carolina University, Greenville, NC; East Carolina University, Greenville, NC; Infectious Disease, Brody School of Medicine, East Carolina University, Greenville, NC; East Carolina University/ Vidant Medical Center, Greenville, NC

“Stat” Multiplex Polymerase Chain ReactionIts Role in Clinical Microbiology

In the laboratory, the department most affected by the introduction of molecular diagnostic tools has been the clinical microbiology laboratory. For organisms such as Clostridium difficile , polymerase chain reaction (PCR) is the gold standard for diagnosis. Incorporation of molecular diagnostic techniques into microbiology laboratories of differing sizes has been hastened by the development of simplified technological methods, individual cassettes incorporating all reagents necessary for diagnosis, and instruments allowing multiple tests to be run at the same time. Companies, such as Cepheid (Sunnyvale, CA), with its GeneXpert technol ogy, even advertise that their tests can be run in a physician’s office. Pressure by the US Food and Drug Administration (FDA) on companies such as Roche has pushed them to change their offerings in molecular diagnosis from analyte-specific reagent kits to a commercially prepared, prepackaged assay with detailed instructions for performance of the test. This change has hastened adoption of molecular methods into the testing menu of laboratories that do not have the resources and staff to perform the extensive and time-consuming validations of assays that are not approved by the FDA. Molecular methods have probably found their greatest use in microbiology laboratories in the diagnosis of viral infections. The reasons for the movement to molecular methods in this arena are varied. The rapid assays for agents such as influenza A and B and respiratory syncytial virus …