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  4. Handle all specimens as potentially infectious. 5. Follow standard biosafety guidelines for handling and disposal of potentially infective material. Specimen Collection and Preparation 1. Blood samples collected with a suitable anticoagulant such as EDTA or Heparin or Oxalate can also be used. 2. No prior preparation of the patient is required before sample collection by approved techniques. 3. Fresh serum/plasma is preferable. Anticoagulated whole blood can also be used as specimen. Serum/plasma may be stored at 2 to 8°C up to 24 hours in case of delay in testing. For long-term storage, freeze the specimen at –20°C for 3 months or –70°C for longer periods. Whole blood should be used immediately and should not be frozen. 4. Repeated freezing and thawing of the specimen should be avoided. 646 Concise Book of Medical Laboratory Technology: Methods and Interpretations 5. Do not use hemolyzed, clotted, contaminated, viscous/turbid specimen. 6. Specimen containing precipitates or

   there is a possibility of occurrence of false positives Heterophile antibodies may be found in disease other than Infectious Mononucleosis. Low titers have been detected in cytomegalic inclusion disease and Toxoplasmosis 5. Incorrect interpretation of results Ensure that the results are interpreted at 3 minute and as per instructions given in the package insert. Positive and negative controls should be run with each series of tests and results should be compared with these Possible causes Solutions 1. Prozoning effect. In serum with very high titers, prozoning may be observed. 2. Hemolyzed samples may have been used. Avoid using hemolyzed samples for testing. 3. Reagents not brought to room temperature. Cold reagents could give false negative results. All reagents must be brought to room temperature before use. Troubleshooting Immutex Problem: False positive results Problem: False negative results Serology/Immunology 645 RAPID TEST FOR IGM ANTIBODIES TO LEPTOSPIRA: LEPTOSPIROSIS (LE

  Studies have cited the presence of heterophile antibodies during the course of infection with infectious mononucleosis. Reagent Immutex is a ready-to-use, uniform suspension of stabilized, specially treated horse erythrocytes highly specific for heterophile antibodies associated with infectious mononucleosis. The reagent does not react with normal Forssman antibodies. Each batch of reagent undergoes rigorous quality control at various stages of manufacture for its specificity, sensitivity and performance. Reagent Storage and Stability Store the reagents at 2 to 8°C. Do not freeze. The shelf-life of the reagents is as per the expiry date mentioned on the reagent vial labels. Principle Immutex is a rapid slide hemagglutination test for the detection of heterophile antibodies. Immutex IM reagent will agglutinate when mixed with serum containing heterophile antibodies. No agglutination indicates absence of heterophile antibodies. Note 1. In vitro diagnostic reagent for laboratory and pro

   The nitrocellulose membrane has lost its flow properties due to absorbance of moisture Check the pouch for pinholes and also check the color of the desiccant (silica gel). A change in color form deep blue to white indicates absorbance of moisture 2. The device is removed from the refrigerator and tested immediately leading to hydration of the sites on the nitrocellulose membrane hence adversely affecting its flow properties The test pouch should be brought to room temperature before being tested Serology/Immunology 643 TEST FOR INFECTIOUS MONONUCLEOSIS (IMMUTEX) (Courtesy: Tulip Group of Companies) Summary Infectious mononucleosis is a self-limited prolonged illness strongly associated with Epstein-Barr Virus. Though specific treatment is rarely required since the disease is usually asymptomatic, potential complications, such as inflammation of the liver, enlargement of the spleen, pericarditis, myocarditis and encephalitis as well as hemolytic anemia associated with this disease,

  antibodies (IgM and IgG) to Dengue virus, if present in the sample. This complex moves further on the membrane to the test region where it is immobilized by the specific human IgM antibody and/or human IgG antibody binding proteins coated on the membrane leading to formation of a colored band which confirms a positive test result. Absence of these colored bands in the test window “T” indicates a negative test result. A built-in control band in the control window “C” appears when the test has been performed correctly, regardless of the presence or absence of antiDengue virus antibodies in the specimen and serves to validate the test performance. Reagents and Materials Supplied Each kit contains: A. lndividual pouches, each containing: 1. Denguecheck-WB (Device) Membrane test assembly predispensed with recombinant Dengue virus specific antigen colloidal gold conjugate, streptavidin gold conjugate, anti-human IgM at test region ‘M’ Protein A at the test region ‘G’ and Biotin at the cont

  6. Prozoning may sometimes be encountered in serum containing very high titers on slide test. 7. Since techniques and standardization vary from laboratory to laboratory a difference of titer corresponding to next or previous titer can be expected. BRUCELLOSIS POSITIVE CONTROL (Courtesy: Tulip Group of Companies) Summary Human brucellosis (diurnal, or undulant fever) is a common febrile illness caused by infection with bacteria of some of the Brucella species (abortus, melitensis). This undulant fever is associated with symptoms, which are often variable and nonspecific with chills, fever, sweats and anorexia. On exposure, the body responds to this antigenic stimulation by producing specific antibodies whose titers rise slowly at early stages and then increases. Specific antibodies to the Brucella species are detectable a few weeks after exposure and are of considerable importance in the Serology/Immunology 639 diagnosis of Brucellosis. Information regarding the titer of antibodies ca