UNIT 5_SPECIALIZED AREA OF MEDICAL TECHNOLOGY_PART 1_STUDENT COPY.pdf

UNIT 5: SPECIALIZED AREAS OF MEDICAL TECHNOLOGY Part 1 HEMATOLOGY Study of blood cells and coagulation encompasses analyses of the concentration, structure, and function of cells in blood; their precursors in the bone marrow; the chemical constituents of plasma or serum intimate...

UNIT 5: SPECIALIZED AREAS OF MEDICAL TECHNOLOGY Part 1 HEMATOLOGY Study of blood cells and coagulation encompasses analyses of the concentration, structure, and function of cells in blood; their precursors in the bone marrow; the chemical constituents of plasma or serum intimately linked with blood cell structure and function; and the function of platelets and proteins involved in blood coagulation. Hematology Procedure Complete Blood Count (CBC) a series of whole-blood tests to determine the quantity and other characteristics of blood cells. (Nelson, 2015) Most laboratories employ automated analyzers to generate CBC Components of CBC RBC Parameters ̶ RBC Count: expressed as the number of cells per cubic mL ̶ Hemoglobin: primary constituent of RBC cytoplasm and transports molecular oxygen from the lungs to tissues. ̶ Hematocrit: ratio of the volume of packed RBC to the volume of whole blood ̶ Mean Cell Volume (MCV): Reflects RBC Diameter (fL) ̶ Mean Cell Hemoglobin (MCH): expresses the mass of hemoglobin per cell(pg) ̶ Mean Cell Hemoglobin Concentration (MCHC): reflects RBC staining intensity and mount of central pallor (g/dL) ̶ RBC Distribution Width (RDW): Expresses the the degree of variation in RBC volume ▪ Anisocytosis – Variation in the RBC size ANISOCYTOSIS RBC Parameters Reference Range SI UNIT Components of CBC WBC Parameters WBC Count: the number of WBCs in 1mm3 of blood ̶ Leukopenia: decreased WBC count ̶ Leukocytosis: Increased WBC count Differential Count: Review, classification, and tabulation of usually 100 white blood cells in a stained peripheral blood film. ̶ Neutrophils, Eosinophils, Basophils, Lymphocytes, Monocytes Manual RBC/ WBC Count Neutrophils Phagocytic cells Mutilobed nuclei Cytoplasm: pink- or lavender-staining granules filled with bactericidal substance Neutrophilia (increased)/ Neutropenia (decreased) Band Neutrophil – slightly less mature than neutrophils with a non-segmented nucleus in a U or S shape Eosinophils Cells with round, bright orange-red cytoplasmic granules filled with proteins involved in immune regulation Eosinophilia Basophils Cells with dark purple, irregular cytoplasmic granules that obscures the nucleus Granules contains histamine Basophilia Lymphocytes Nearly round, larger than RBC, round featureless nuclei and thin rim of non granular cytoplasm Lymphocytosis/ Lymphocytopenia Provides host immunity Monocytes Slightly larger diameter than other WBCs, blue-gray cytoplasm with fine azure granules, nucleus is usually indented or folded Immature macrophage Monocytosis WBC Parameter Reference Range Components of CBC Platelets Parameters Platelet Count: Number of platelets per cubic mm. Mean Platelet Volume (MPV): Average size of platelets Hematology Procedure Coagulation Test: Test for clotting factors Prothrombin Time (PT) Partial Thromboplastin Time (activated Partial Thromboplastin Time) (PTT or aPTT) Thrombin Time Fibrinogen Assay D-dimer Assay MICROBIOLOGY focused on the detection, characterization, and quantification of pathogens from patient samples to enable the diagnosis, treatment, and management of infections (Bachman, 2019) Bacteria, Fungi, Virus, Parasites Microbiology Procedure Gram Stain Rapidly provides information that is used by the clinician for selecting appropriate antimicrobial therapy. helps the clinical laboratory scientist assess the quality of the specimen and the extent to which certain organisms recovered in culture will be worked up. Reagents: ̶ Primary stain: crystal violet ̶ Mordant: Gram iodine ̶ Decolorizer: Acetone-alcohol ̶ Secondary Stain: safranin Examples Gram-positive cocci: Staphylococcus, Streptococcus Gram-negative cocci: Neisseria Gram-positive bacilli: Bacillus Gram-negative coccobacilli: Escherichia Gram-negative bacilli: Pseudomonas Microbiology Procedure Acid Fast Stain used to stain organism that have a high lipid and wax content in their cell walls and do not stain well with traditional bacterial stains. Example: Mycobacterium tuberculosis, Coccidian parasites (Cystoisopora spp.) Reagents: ̶ Primary Stain: Carbol fuchsin ̶ Mordant: Heat (Ziehl-Neelsen) or Detergent/ Tergitol (Kinyoun) ̶ Decolorizer: Acid-alcohol ̶ Secondary Stain: Methylene Blue/ Malachite Green Direct Sputum Smear Microscopy (DSSM) fundamental to the detection of infectious cases and is recommended for case finding among adults and children who can expectorate (NTP) 10% Potassium Hydroxide (KOH) KOH clears the specimen of proteinaceous and keratinous substances making visualization of fungal elements easier Skin scrapings/ Nails Clippings Culture and Sensitivity Types of Culture Media ̶ Nonselective media support the growth of most nonfastidious microbes (Ex. Blood Agar Plate) ̶ Selective media support the growth of one type or group of microbes but not another. ▪ MacConkey-enteric gram-negative bacilli, Columbia agar with colistin and nalidixic acid (CNA) is selective for gram-positive organism ̶ Differential media allow grouping of microbes based on different characteristics demonstrated on the medium. ̶ Enriched media contain growth enhancers that are added to nonselective agar to allow fastidious organisms to flourish (Ex. Chocolate Agar) ̶ Enrichment broth is a liquid medium designed to encourage the growth of small numbers of a particular organism while suppressing other flora present. ▪ Lim broth (Todd Hewitt broth with CNA) is used to enhance the growth of group B streptococci. ▪ Thioglycollate broth is an example of a supplemental broth media. Antimicrobial susceptibility testing performed on bacteria and fungi isolated from clinical specimens to determine which antimicrobial agents might be effective in treating infections caused by these organisms. Susceptibility testing on bacteria is often performed by a disk diffusion or dilution (minimal inhibitory concentration [MIC]) method. Standards that describe these methods are published and frequently updated by the Clinical and Laboratory Standards Institute (CLSI) Medium: Mueller-Hinton Agar Example