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   1. Objective The objective of the Complement Fixation Test (CFT) was to detect the presence of specific antibodies or antigens in a patient's serum by observing complement-mediated lysis of indicator red blood cells. 2. Principle The test was based on the ability of antigen–antibody complexes to fix complement. If the patient's serum contained specific antibodies, they formed a complex with the added antigen and fixed the complement. When sheep red blood cells (SRBCs) coated with anti-sheep RBC antibodies were added, no hemolysis occurred, indicating a  positive  result. If there were no antibodies, the complement remained free and lysed the indicator SRBCs, indicating a  negative  result. 3. Materials Used Patient serum (heat-inactivated) Known antigen Complement (usually guinea pig complement) Sheep red blood cells (SRBCs) Hemolysin (anti-sheep RBC antibodies) Controls (positive and negative) Incubator and water bath 4. Procedure The patient's serum wa...

   1. Objective The objective of this test was to evaluate the functionality of platelets by measuring their ability to aggregate in response to various agonists. 2. Principle The test was based on the principle that platelets, when exposed to aggregating agents (agonists), clump together. This aggregation caused a change in light transmission through platelet-rich plasma (PRP), which was measured by an aggregometer. A functional platelet population exhibited a characteristic response to each agonist. 3. Materials Used Patient’s citrated blood Centrifuge Platelet aggregometer Aggregating agents: ADP, collagen, epinephrine, arachidonic acid, ristocetin Cuvettes and stir bars Pipettes 4. Procedure Blood was collected in a citrate tube and centrifuged at low speed to obtain PRP. The remaining blood was centrifuged at higher speed to prepare platelet-poor plasma (PPP) for use as a blank. PRP was added into a cuvette with a magnetic stir bar and placed in the aggregometer. A known ...

  1. Objective The objective of the test was to detect the presence of Vibrio cholerae, the bacterium responsible for cholera, in stool samples or rectal swabs, aiding in diagnosis and outbreak control. 2. Principle The test was based on isolating and identifying Vibrio cholerae using culture, microscopy, or rapid immunochromatographic test kits. Culture allowed confirmation, while rapid tests gave quicker preliminary results by detecting cholera antigen in stool. 3. Materials Depending on the method used: ✔ For Culture: • Fresh stool sample or rectal swab • Transport media (Cary-Blair) • Selective media (Thiosulfate Citrate Bile Salts Sucrose agar – TCBS) • Enrichment broth (Alkaline Peptone Water) • Microscope and staining reagents • Oxidase reagent • Biochemical test kits ✔ For Rapid Cholera Dipstick Test: • Stool sample • Cholera antigen rapid test cassette • Extraction buffer • Dropper • Timer Read more test 4. Procedure 🧪 A. Culture Method 1. Stool ...

   1. Objective The objective of this test was to detect the presence of HIV (Human Immunodeficiency Virus) antibodies or antigens in a patient's blood or serum to screen for HIV infection. 2. Principle The test was based on the detection of HIV-specific antibodies (IgG, IgM) and/or p24 antigen using Enzyme-Linked Immunosorbent Assay (ELISA), Rapid Immunochromatographic Tests, or Western Blot. In some advanced cases, nucleic acid testing (NAT) was used for early detection. 3. Materials Used HIV Rapid Test Kit (e.g., Determine, Uni-Gold, First Response) Patient's blood or serum sample Buffer solution Micropipette and tips Timer Biohazard disposal 4. Procedure A drop of patient’s whole blood or serum was placed on the test device sample pad. Two drops of buffer solution were added. The sample was allowed to migrate across the test strip by capillary action. Results were read after 15–20 minutes. Control and test lines were observed to interpret the result. 5. Result Positive: ...

   1. Objective The objective of the experiment was to count and analyze different types of cells in a given sample using flow cytometry based on light scatter and fluorescence properties. 2. Principle Flow cytometry was used to count and characterize cells as they passed individually through a laser beam. Cells were differentiated by their size (forward scatter), internal complexity (side scatter), and fluorescence intensity if stained with specific markers. Counting was achieved using volumetric analysis or by adding a known number of fluorescent counting beads. 3. Materials Used Flow cytometer (e.g., BD FACSCanto) Cell suspension (e.g., peripheral blood, cultured cells) Fluorescently labeled antibodies (e.g., CD45, CD3) Counting beads (optional) PBS (phosphate-buffered saline) FACS tubes Vortex mixer and pipettes 4. Procedure The cell suspension was prepared and filtered to remove clumps. Fluorescent antibodies were added to label specific cell populations. The samples were...

   1. Objective: To detect and identify unexpected antibodies in a patient’s serum that may react with red blood cell antigens, especially before transfusion. 2. Principle: Patient serum is mixed with reagent red cells of known antigen profiles. Agglutination indicates the presence of antibodies. Identification involves comparing reaction patterns with known antigen matrices. 3. Materials: Patient serum/plasma Screening and identification red cell panels LISS or saline Antiglobulin reagent (Coombs reagent) Test tubes or gel cards Centrifuge, incubator 4. Procedure: Mix patient serum with screening cells → incubate. Wash to remove unbound antibodies. Add antihuman globulin → check for agglutination. If positive, proceed to identification with an extended red cell panel. Compare agglutination pattern to known antigen profiles. 5. Result Interpretation: No agglutination : No detectable antibodies. Agglutination with specific cells : Suggests presence of particular antibody (e.g.,...

  1. Objective: To detect antiphospholipid antibodies in patient plasma, especially in suspected cases of antiphospholipid syndrome, using the Dilute Russell’s Viper Venom Time (dRVVT) test. 2. Principle: The dRVVT measures the time it takes for plasma to clot after the addition of diluted Russell's viper venom, which directly activates factor X. In the presence of antiphospholipid antibodies, especially lupus anticoagulant, the clotting time is prolonged. A confirmatory test with excess phospholipids is used to demonstrate correction. 3. Materials Required: Patient citrated plasma Normal pooled plasma (control) Russell’s viper venom reagent (screening and confirmatory) Calcium chloride Platelet-poor plasma Coagulometer or water bath with stopwatch Test tubes and pipettes 4. Procedure: Collected citrated blood and prepared platelet-poor plasma. Added venom reagent to both patient and control plasma. Added calcium chloride to initiate clotting. Measured clotting time (screen). Repea...

    1. Objective: To determine the concentration (titer) of anti-D (Rh) antibodies in a patient's serum—especially in Rh-negative pregnant women—to assess risk of Hemolytic Disease of the Fetus and Newborn (HDFN). 2. Principle: Serial dilutions of the patient’s serum are reacted with Rh-positive red cells. The highest dilution at which agglutination still occurs is the  antibody titer . This provides a quantitative estimate of antibody strength. 3. Materials Required: Patient's serum Rh(D) positive red blood cells (usually R1R1) Phosphate-buffered saline (PBS) 2–5% red cell suspension Incubator at 37°C Centrifuge Test tubes Antihuman globulin (AHG or Coombs reagent) 4. Procedure: Prepare  serial twofold dilutions  of the patient’s serum (e.g., 1:1 to 1:1024). Add equal volume of 2–5% Rh(D)-positive RBC suspension. Incubate at 37°C for 30–60 minutes. Wash cells 3–4 times with PBS. Add AHG reagent, centrifuge, observe for agglutination. The  highest dilution ...

  1. Objective The objective of the experiment was to detect and quantify disease-specific antigens or antibodies in hematological disorders using the ELISA technique. 2. Principle The ELISA technique was based on antigen-antibody interaction. Either the antigen or antibody was immobilized on a solid surface (usually a microtiter plate), and a corresponding enzyme-labeled antibody was used for detection. Upon addition of a chromogenic substrate, a color change occurred, which was measured spectrophotometrically and correlated with the concentration of the target molecule. 3. Materials Used Microtiter ELISA plate Patient serum or plasma samples Known standards and controls Enzyme-conjugated antibodies (e.g., anti-FVIII for Hemophilia A) Substrate (e.g., TMB – Tetramethylbenzidine) Stop solution (e.g., sulfuric acid) Plate washer and reader Pipettes and sterile tips 4. Procedure The microtiter plate was coated with capture antibody and incubated. Wells were blocked with blocking buff...

  1. Objective The objective of this test was to determine the  sensitivity of bacterial isolates  to various  antibiotic agents , helping guide effective antimicrobial therapy.   2. Principle The test was based on the  inhibition of bacterial growth  by antibiotics. The  Kirby-Bauer disc diffusion method  was used, where antibiotic-impregnated discs were placed on an agar plate inoculated with bacteria. The  zone of inhibition  around each disc indicated the effectiveness of the antibiotic. 3. Materials Pure bacterial isolate Mueller-Hinton agar plates Antibiotic discs (e.g., ampicillin, ciprofloxacin, ceftriaxone) Sterile swabs  McFarland standard (0.5) Incubator (35–37°C) Ruler or caliper CLSI guideline chart for interpretation 4. Procedure A standardized bacterial suspension (0.5 McFarland) was prepared. The suspension was evenly spread onto Mueller-Hinton agar using a sterile swab. Antibiotic discs were placed on the agar ...

                                   1. Objective To detect  Blastocystis hominis  in stool specimens using  microscopic, culture, or molecular methods , aiding in the diagnosis of  blastocystosis . 2. Principle Blastocystis hominis  is an  intestinal protozoan  with variable forms (vacuolar, granular, amoeboid). Diagnosis is made by detecting  characteristic vacuolated forms  in stool through: Direct wet mount microscopy Stool concentration techniques Permanent staining (e.g., trichrome) Culture in Jones' medium  (for research/lab confirmation) PCR  (for species-level identification) 3. Materials Fresh stool specimen Saline and Lugol’s iodine Glass slides and coverslips Formalin-ether for concentration Trichrome stain (optional) Culture media (optional) Microscope PPE and waste disposal supplies 4. Procedure A.  Direct Wet Mount Mix stool s...