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Urinary urobilinogen may be increased in the presence of a hemolytic process such as hemolytic anemia. It may also be increased with infectious hepatitis, or with cirrhosis. Comparing the urinary bilirubin result with the urobilinogen result may assist in distinguishing between red cell hemolysis, hepatic disease, and biliary obstruction. Urobilinogen is increased in hemolytic disease and urine bilirubin is negative. Urobilinogen is increased in hepatic disease, and urine bilirubin may be positive or negative. Urobilinogen is low with biliary obstruction, and urine bilirubin is positive. Reagent strips methods however, cannot distinguish normal urobilinogen from absent urobilinogen, as might be seen in complete biliary obstruction.

Suppola JP. Kuikka A. Vaara M. Valtonen VV. Comparison of risk factors and outcome in patients with Enterococcus faecalis vs Enterococcus faecium bacteremia. Scandinavian Journal of Infectious Diseases. 30(2):153-7, 1998.The purpose of our study was to determine retrospectively the risk factors for the acquisition of Enterococcus faecalis vs E. faecium bacteremia, as well as the clinical outcomes of these patients.62 patients with Enterococcus faecalis bacteremia were compared to 31 patients with E. faecium bacteremia. Haematologic malignancies, neutropenia, high-risk source and previous use of aminoglycosides, carbapenems, cephalosporins and clindamycin were significantly associated with E. faecium bacteremia. Instead, urinary catheterization was found to be related to Enterococcus faecalis bacteremia. The mortality rates within 7 d and 30 d were 13% and 27%, respectively, in patients with E. faecalis bacteremia and 6% and 29%, respectively, in patients with E. faecium bacteremia.There was no difference in mortality between E. faecalis and E. faecium bacteremia, nor was there a difference in seriousness of disease at the time of bacteremia. In the subgroups of patients with monomicrobial or clinically significant E. faecalis vs E. faecium bacteremia, the mortality rates were similar to the results of all subjects.Our results do not support the theory that E. faecium would be a more virulent organism than E. faecalis

Hershow RC. Khayr WF. Smith NL.: A comparison of clinical virulence of nosocomially acquired methicillin-resistant and methicillin-sensitive Staphylococcus aureus infections in a university hospital (University of Illinois at Chicago). Infection Control & Hospital Epidemiology. 13(10):587-93, 1992OBJECTIVES: To compare the clinical virulence of nosocomially acquired methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-sensitive S. aureus (MSSA) infections in 1989.DESIGN: A retrospective comparison of host factors, in-hospital exposures, sites of infections, and outcomes of patients with nosocomial MRSA and MSSA infections. PARTICIPANTS: Forty-four adult patients with nosocomial S.aureus infections.RESULTS: The 22 MRSA-infected and 22 MSSA-infected persons were similar regarding mean age, gender, underlying diseases, and exposure to surgery. Before developing infection, MRSA-infected persons were more likely to have received antibiotics and to have stayed in the hospital > 2 weeks. Bacteremia was the most common presentation in the MRSA and MSSA groups (55% and 59%, respectively). Infectious complications and death were infrequent in both groups.CONCLUSIONS: MRSA and MSSA strains infect patients with similar demographic features and underlying diseases, but MRSA infections are significantly more common among patients with previous antibiotic therapy and a prolonged preinfection hospital stay. Clinical presentations and outcomes did not differ significantly between the 2 groups. Thus, similar to studies in the early 1980s, our findings do not suggest greater intrinsic virulence of MRSA.

Gelfand MS. Bakhtian BJ. Simmons BP.: Spinal sepsis due to Streptococcus milleri: two cases and review. Reviews of Infectious Diseases. 13:559-63, 1991We have recently cared for two patients with spinal sepsis secondary to infection with Streptococcus milleri.One patient had a spinal epidural abscess and the other had meningitis as well as a spinal subdural empyema.A review of the English-language literature revealed only two previously reported cases of spinal epidural abscess due to S. milleri and no cases of spinal subdural empyema due to S. milleri. We report two cases of spinal sepsis due to S. milleri and discuss pertinent literature.

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.

At the highest level are the “national” laboratories. Examples would include those operated by CDC, the United States Army Medical Research Institute for Infectious Diseases, and the Naval Medical Research Center. These laboratories have very unique resources to handle highly infectious agents and the ability to identify specific agent strains.

Biological attacks involve bacteria, viruses or natural toxins. The effects of toxins can be immediate but for bacteria and viruses the effects may not be apparent for weeks. A bio-terrorist may attack by infecting animals, contaminating food and water, spraying bacteria or viruses into the air. In infections such as smallpox and plague, once a few individuals are infected they can further spread the disease from person to person. An attack could also come from through a building’s ventilation system, the mail, or even through exposure to an infected terrorist seeking to spread disease during an infectious stage.

Commercially prepared controls come in either assayed or unassayed forms. Assayed controls are tested by multiple methods before sale, and are sold with the results of the tests. Assayed controls: are more expensive than unassayed controls are used to evaluate accuracy and precision avoid laboratory errors in determining control values may only be suitable for specific methods or conditionsWhile the manufacturer's control values can be used to some extent to measure accuracy, the best measure of accuracy is certified reference material.Unassayed controls are not tested by the manufacturer before they are sold. The control values for these materials must be determined by the individual laboratory. Unassayed controls: are less expensive than assayed controls are used to evaluate precision only avoid manufacturer error in determining control values control values are customized to the laboratory's own methods and conditionsA final note: although commercially available control materials are screened for hepatitis antigens and HIV antibodies, control materials should still be handled with precautions, since they contain biological materials and could contain infectious agents.

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.

As a healthcare worker, you come into contact with bloodborne pathogens. These are infectious organisms, usually viruses, which live in human blood and other potentially infectious body fluids.The most important ones are... Hepatitis B Virus (HBV) Human Immunodeficiency Virus (HIV)

A person infected with HBV can spread the virus soon after the initial infecting incident, and the infectious period continues through the acute and chronic illness.

Work practice controls affect the transport of blood and other potentially infectious materials.

Gloves must be worn: when there is a reasonable chance of exposure to blood, other infectious body fluids, mucous membranes, or nonintact skin, during vascular access procedures, including phlebotomy, or when handling contaminated items or surfaces.

Treat all blood & body fluids as if they were infectious.Always wear gloves during vascular access procedures.

Bloodborne pathogens are infectious micro-organisms which live in the bloodstream.You can be exposed to bloodborne pathogens if you are injured with a contaminated needle.You can also be exposed if your mucous membranes, including eyes, mouth, or the inside of your nose come into contact with contaminated body fluids.

Potentially infectious body fluids include: Blood, Semen, Vaginal Secretion, Peritoneal, pericardial and pleural fluids, and Saliva Sweat and tears are not generally considered infectious. It is important to remember that bloodborne pathogens are not transmitted by casual contact, like a handshake.

The basic laboratory skills that you will need to do a semen analysis include: Using a microscopePerforming manual cell counts and doing calculations to determine the concentration of those cells per milliliter of fluidMeasuring volumeMeasuring pHMeasuring viabilityKnowledge of OSHA regulations for handling potentially infectious human fluids

The Mycobacterium tuberculosis organism is spread through infectious droplet nuclei.When a person infected with pulmonary tuberculosis coughs, sneezes, shouts, or sings, the infectious particles are expelled into the air.The risk of infection is related to both concentration of infectious droplet nuclei and duration of exposure.

Biosafety level 3 practices, safety equipment, and facility design and construction are applicable to microbiology laboratories that work with indigenous or exotic agents with a potential for respiratory transmission, and which may cause serious and potentially lethal infection. Mycobacterium tuberculosis is assigned to this biosafety level. At biosafety level 3, laboratory manipulations should be performed in a Class l or Class ll biosafety cabinet (BSC) or other physical containment device. Secondary barriers include controlled access to the laboratory and ventilation requirements that minimize the release of infectious aerosols from the laboratory. Secondary barriers should include self-closing double-door access and negative airflow into the laboratory. Exhausted air must not be recirculated.

The following pages in this presentation includes a series of white blood cell abnormalities that may be identified in a peripheral blood smear. Many of the cases will simulate the practice of a peripheral smear review by a hematology morphologist. He/she must asses what responses in patient care may be triggered by the clinician attempting to interpret the reported findings on a peripheral smearObservations of white blood cell abnormalities in the peripheral blood smear should be reported so as to direct the physician to an immediate specific diagnosis, such as: (1) atypical lymphocytes suggesting infectious mononucleosis rather than leukemia, (2) toxic granules in neutrophils as in acute infections, or atypical granules suggesting a genetic disorder, (3) an unusual mix of cells, such as too many or too few neutrophils, monocytes, or other myeloid cells, and (4) the presence of giant platelets, myelocytes, or other cells suggesting a myelodysplastic syndrome.In summary, laboratory data should be presented to clinicians in a user friendly way to promote effective decision making. The design of the data base of information must be directed toward providing clinically helpful information clearly and quickly in order to facilitate appropriate action in terms of optimizing patient care outcomes.d

The presence of atypical inclusions within the cytoplasm of neutrophils and other leukocytes should lead to a clinical investigation of the setting for these findings.Atypical neutrophil inclusions may be seen in the following disorders: Chediak-Higashi syndrome, May-Hegglin anomaly, Alder-Reilly anomaly, Fechtner , Sebastian, Epstein and Alport-like syndromes and in infectious and toxic conditions (in the form of Doehle bodies).Although a specific entity may not be evident from examination of the peripheral blood alone, it is important that hematology technologists include a comment reporting on the presence of these inclusions or granules. A clinical investigation with further hematologic and genetic studies may then appropriately be considered.Many of the disorders with atypical neutrophil cytoplasmic granules are also associated with platelet abnormalities, particularly giant platelets (lower photograph).Therefore, when atypical granules are recognized, scanning of the peripheral blood smear for atypical platelets may be revealing. These observations serve as readily identifiable markers for acquired and genetic human maladies, and as a guide for unraveling the reasons for a patient's suffering and impaired health.

A 14 year-old boy came to the physician's office with a sore throat that progressively worsened over a three day period. His posterior pharynx was swollen ,shiney and erythematous. The boy complained of pain on swallowing. His temperature was 98.5F. A rapid direct streptococcal antigen test was positive. However, his symptoms did not subside over the next two days while on antibiotic therapy. Anorexia and nausea were persistent and compounded by a frontal headache. Cervical lymph nodes became noticeably enlarged. The results of the CBC were: WBC 11.9/mm3 with 17% segmented neutrophils, 5% bands, 72%(60% atypical--see photograph)lymphocytes and 6%monocytes. All red cell findings were normal. A monospot test was positive. This is a case of group-A streptococcal infection superimposed on infectious mononucleosis. Symptoms subsided in 3 weeks following completion of the antibiotic therapy.