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Podschun R. Ullmann U.: Klebsiella spp. as nosocomial pathogens: epidemiology, taxonomy, typing methods, and pathogenicity factors Clinical Microbiology Reviews. 11(4):589-603, 1998Bacteria belonging to the genus Klebsiella frequently cause human nosocomial infections. In particular, the medically most important Klebsiella species, Klebsiella pneumoniae, accounts for a significant proportion of hospital-acquired urinary tract infections, pneumonia, septicemias, and soft tissue infections.The principal pathogenic reservoirs for transmission of Klebsiella are the gastrointestinal tract and the hands of hospital personnel. Because of their ability to spread rapidly in the hospital environment, these bacteria tend to cause nosocomial outbreaks. Hospital outbreaks of multidrug-resistant Klebsiella spp., especially those in neonatal wards, are often caused by new types of strains, the so-called extended-spectrum-beta-lactamase (ESBL) producersThe incidence of ESBL-producing strains among clinical Klebsiella isolates has been steadily increasing over the past years. The resulting limitations on the therapeutic options demand new measures for the management of Klebsiella hospital infections.While the different typing methods are useful epidemiological tools for infection control, recent findings about Klebsiella virulence factors have provided new insights into the pathogenic strategies of these bacteria. Klebsiella pathogenicity factors such as capsules or lipopolysaccharides are presently considered to be promising candidates for vaccination efforts that may serve as immunological infection control measures.

Piscitelli SC., Shwed J., Schreckenberger P., Danziger LH. Streptococcus milleri group: renewed interest in an elusive pathogen. European Journal of Clinical Microbiology & Infectious Diseases.11:491-8, 1992The following review examines the bacteriological characteristics, epidemiology, pathogenicity and antimicrobial susceptibility of the "Streptococcus milleri group". "Streptococcus milleri group" is a term for a large group of streptococci which includes Streptococcus intermedius, Streptococcus constellatus and Streptococcus anginosus.Usually considered commensals, these organisms are often associated with various pyogenic infections including cardiac, intra-abdominal, subcutaneous and central nervous system infections, particularly with the formation of abscesses.Organisms of the "Streptococcus milleri group" are often unrecognized pathogens due to the lack of uniformity in classifications and difficulties in microbiological identification. Penicillin G, cephalosporins, clindamycin and vancomycin all possess activity against these streptococci.Use of agents with poor activity may promote infections with "Streptococcus milleri group" and allow it to exhibit its pathogenicity. An understanding of these organisms may aid in their recognition and proper treatment.

Cunningham MW.: Pathogenesis of group A streptococcal infections. Clinical Microbiology Reviews. 13):470-511, 2000Group A streptococci are model extracellular gram-positive pathogens responsible for pharyngitis, impetigo, rheumatic fever, and acute glomerulonephritis. A resurgence of invasive streptococcal diseases and rheumatic fever has appeared in outbreaks over the past 10 years, with a predominant M1 serotype as well as others identified with the outbreaks.Emm (M protein) gene sequencing has changed serotyping, and new virulence genes and new virulence regulatory networks have been defined. The emm gene superfamily has expanded to include antiphagocytic molecules and immunoglobulin-binding proteins with common structural features.At least nine superantigens have been characterized, all of which may contribute to toxic streptococcal syndrome. An emerging theme is the dichotomy between skin and throat strains in their epidemiology and genetic makeup. Eleven adhesions have been reported, and surface plasmin-binding proteins have been defined.The strong resistance of the group A streptococcus to phagocytosis is related to factor H and fibrinogen binding by M protein and to disarming complement component C5a by the C5a peptidase. Molecular mimicry appears to play a role in autoimmune mechanisms involved in rheumatic fever, while nephritis strain-associated proteins may lead to immune-mediated acute glomerulonephritis. Vaccine strategies have focused on recombinant M protein and C5a peptidase vaccines, and mucosal vaccine delivery systems are under investigation.

Rocourt J. Jacquet C. Reilly A.: Epidemiology of human listeriosis and seafoods. International Journal of Food Microbiology. 62:197-209, 2000While rarely diagnosed prior to 1960, more than 10,000 cases of listeriosis were recorded in the medical literature between 1960 and 1982, and thousands more have been reported annually world-wide. This widespread increase in reporting is most likely due to demographic trends and changes in food production, processing and storage, especially the extended cold food chain and the ability of Listeria monocytogenes to grow at low temperaturesL. monocytogenes is a bacterium responsible for opportunistic infections, preferentially affecting individuals whose immune system is perturbed, including pregnant women, newborns, people over 65 years, immunocompromised patients, such as cancer victims, transplant recipients, people on hemodialysis and AIDS patients.Thus, the increasing lifespan and medical progress allowing immunodeficient individuals to survive, partially explains the increasing incidence of listeriosis. Moreover, L. monocytogenes is ubiquitous and can grow at temperatures as low as 0 degrees C. At this temperature growth is very slow.The expansion of the agro-food industry, the widespread use of systems of cold storage and changes in consumers demands have led to a large increase in the pool of Listeria that can cause food-borne infections.

Robinson LG. Kourtis AP.: Tale of a toothpick: Eikenella corrodens osteomyelitis. Infection. 28(5):332-3, 2000Tale of a Toothpick is a case of Eikenella corrodens osteomyelitis in a young woman, that resulted from puncture of her foot with a toothpick.The epidemiology, microbiology, common clinical presentations and therapy of E. corrodens are reviewed.A brief summary of the extent of toothpick injuries and their infectious complications are also presented.

A molecular method may be the test method of choice for a variety of reasons, including the following: Organisms of interest, especially in microbiology or virology, may be extremely slow growing, fastidious or extremely limited in quantity. Other technologies lack the necessary sensitivity or specificity Patient population requirements

The frontline clinical microbiology laboratories are known as “sentinel laboratories”. The sentinel laboratories play a key role in the nation’s preparedness efforts. These laboratories perform the initial screening of clinical specimens for potential pathogens (rule-out) and refer specimens or isolates to a state or local public health laboratory at the reference level of the LRN. There are two kinds of sentinel laboratories: advanced and basic. Classification depends on their biological safety level and analytical capability.

Public health laboratory scientists are also regulated by the Board. The table below outlines the various requirements for applicants to receive licensure for a public health laboratory. Public Health Laboratory RequirementsDirectorFulfill the same requirements as a clinical laboratory directorSupervisorBe certified by National Registry in Clinical Chemistry or American Society for MicrobiologyBe licensed as a technologistHave five year's relevant experiencePass the state examTechnician (microbiology)Have a Bachelor's degree in one of the biological sciencesObtain American Society for Microbiology or the National Registry in Microbiology Certification in Public Health Microbiology Technician (chemistry)Have a Bachelor's degree in one of the chemical, biological, or physical sciencesObtain National Registry of Clinical Chemistry Certification in Public Health ChemistryTechnician (conditional)Have a Bachelor's degree in one of the chemical or biological sciencesPerform tests only under the direct supervision of a licensed pathologist, director, supervisor, or technologist.Receives a conditional two-year license, which may be renewed only once A license from the Board of Clinical Laboratory Personnel allows you to work in a public health laboratory at the same level and specialty.

Specialists in microbiology perform testing to diagnose and stop the spread of infectious organisms, including bacteria, viruses, and parasites. Specialists should be able to isolate and identify a wide variety of these organisms. Testing procedures include direction examination and antigen detection methods. Specialists in serology and immunology measure antibodies to infectious organisms. Specialists should be familiar with all serology techniques (except those specific to immunohematology). This specialty includes all lab procedures performed in the specialty of histocompatibility. Specialists in hematology must be able to identify and evaluate cells in blood and bone marrow and identify disorders of these cell. Specialists should be familiar with routine and special tests to determine the number, morphology, and function of cells in body fluid.

Busy hospital laboratory in a 350 bed urban hospital that provides laboratory testing for the hospital and for the hospital's outreach testing laboratory. A medical technologist in the microbiology department receives a call from a friend who works in a laboratory in a physician office. The physician is not a regular client of the laboratory currently but uses another laboratory for most of their work. The microbiologist knows that the sales department would like to get this account. The friend explains to her that she is doing a quality control check on her in-office microbiology testing and her regular laboratory will do it but is going to charge her for it. She asks the microbiologist if she will do it for free since it is quality control, not Medicare and is not going to be billed to anyone.She tells the microbiologist that she would like to use the hospital lab for everything but her doctor insists on using the competitor. She indicates that the favor might help get the doctor to try the hospital laboratory for other tests. The microbiologist should:Correct Answer: Explain to her friend that if the hospital does the tests for no charge on the promise of other referrals, both the physician office and the hospital could be liable for violations of the antikickback statute.Discussion: The antikickback statute is implicated in this scenario because the free testing is solicited on the condition that other referrals may occur as a result of providing the favor. In fact, the solicitation itself is a violation of the law. The fact that Medicare patients are not specifically mentioned in the scenario is not sufficient to remove the risk. The technologist should also report the incident to the Compliance Officer and seek advise about what documentation, if any, should be kept concerning the incident.

It is important to always dispose of contaminated wastes properly!Examples of contaminated wastes: Microbiology waste and pathology wasteAll body fluids, such as pleural fluids Contaminated sharps and blood specimens

Validated material for the different testing areas in a laboratory (such as chemistry, hematology, and microbiology) are provided several times a year. Participating laboratories test the specimens and return results to the proficiency testing source. The laboratory’s performance is then evaluated using the comparative method mean as the target value plus or minus a defined limit. In general, the evaluation report will show: number of laboratories comprising the peer groupcomparative mean of the group for that particular analyte the laboratory’s performance compared to the peer group whether the performance was satisfactory or unsatisfactory.

The process of culture, isolation and identification of microorganisms is basic to medical microbiology. When a culture shows signs of growth, the process of identification includes examining the following characteristics:appearance of the colonies in the culture mediumstaining reactionappearance of stained organismssizeshapearrangement of bacterial cellsThis type of preliminary identification may help the physician to initiate the appropriate antibiotic treatment.

Glassy, Eric F.,(Ed). Color Atlas of Hematology: An Illustrated Field Guide Based on Proficiency Testing. 1998. College of American Pathologists Hematology and Cliical Microbiology Research Committee. College of American Pathologists, Northfield, IL 60093-2750.Hookey,L., Dexter, D., Lee,D. H. The Use and Interpretation Of Quantative Terminology In Reporting Red Blood Cell Morphology. Laboratory Hematology 7:85-88, 2001.Peterson P, Blomberg DJ, Rabinovitch A, Cornbleet PJ. Physician Review of the Peripheral Blood Smear: When and Why. For the Hematology and Clinical Microscopy Resource Committee of the College of American Pathologists. Laboratory Hematology 7:175-179, 2001

Some procedures increase the potential for TB risk because they create aerosols. They include: Sputum induction and aerosol treatments Bronchoscopy Endotracheal intubation and suctioning Autopsy Microbiology processing TB specimens Surgical drainage of TB abscesses

Laboratory workers who handle infectious materials in the microbiology laboratory should be aware of the work practices, safety equipment, and barriers that will protect them and others in the area from infectious agents. The Centers for Disease Control and Prevention (CDC) and the National Institutes of Health (NIH) created guidelines to assist laboratories in developing safe practices based on the infectious agents that are handled. These guidelines are referred to as Biosafety Levels 1 through 4. Each increasing number represents increased risk, requiring more stringent work practice and increasingly protective safety equipment and barriers. A copy of the Guidelines can be obtained from the CDC or accessed online at:http://www.cdc.gov/OD/ohs/biosfty/bmbl5/bmbl5toc.htm