Laboratory samples المحاضرة الاولى كلية بلاد الرافدين.pptx

Laboratory samples

1. By: Dr. Mohammed Mohammed Abdullah Yassin Bachelor In Medical Laboratory Science (MLS) Diagnostic skills of laboratory tests for common disease cases and reading their results:

2. Overview of course The course gives the medical students a broad knowledge about t ype of Laboratory Samples and laboratory analysis topics. It enables students to get the necessary concepts about examinations of human samples including blood, urine , semenal , cerebrospinal, synovial and serous fluids, along with understanding their clinical significance . It emphasizes on the proper collection methods, preservation, transporting, handling, processing, analytical methods, quality control procedures and the interpretations of the results of testing clinical Laboratory samples.

3. Main topics Types o f Laboratory Samples Introduction Reasons for Ordering a Laboratory Test Questions to Ask Before Ordering a Laboratory Test Laboratory Testing Cycle Types of Laboratory samples Blood sample Urine sample Stool sample Seminal fluid sample Cerebrospinal fluid (CSF) sample Synovial fluid and Amniotic fluids sample s SEROUS FLUIDS: pleural, pericardial and peritoneal fluids samples Tears, salvia, sweat, cerumen, Mucus, sputum, Milk , samples , … etc. Tissue and swap samples lecture 1

4. INTRODUCTION Lab tests, along with a health history and physical exam, are used by physicians to diagnose and manage health conditions. When the body is healthy, it functions normally in a state of homeostasis or equilibrium. When the body is in homeostasis, the values for fluids, chemicals, electrolytes, and secretions ( hormones ) are typically within an acceptable or “normal” range. When the body has a pathologic condition (e.g. a disease state), these ranges can change as a result of an imbalance in your body. The disease can cause the imbalance, and vice versa, the imbalance may cause the disease. Lab tests can help identify these imbalances which will aid the medical professional in understanding and treating the underlying problem. 

5. Reasons for Ordering a Laboratory Test A diagnostic test could be used in clinical settings for confirmation/exclusion, triage, monitoring, prognosis, or screening: Diagnosis : Confirmation/exclusion (to rule in or rule out a diagnosis). Monitoring : A repeated test that allows assessing the efficacy of an intervention ( eg , the effect of drug therapy). Screening: Presence of the disease in apparently asymptomatic persons ( eg , for congenital hypothyroidism via neonatal thyroxine testing). Prognosis: Assessment of an outcome or the disease progression. Research (to understand the pathophysiology of a particular disease process).

6. Questions to Ask Before Ordering a Laboratory Test An understanding of which laboratory tests are appropriate to order in the diagnosis and follow up of a patient’s medical condition should include prior consideration of the answers to the following questions: Why is the test being ordered? What are the consequences of not ordering the test? How good is the test in discriminating between health versus disease? How are the test results interpreted? How will the test results influence patient management and outcome? The answers to these questions are critical to the optimal selection and cost-effective use of laboratory tests likely to benefit patient management.

7. Laboratory Testing Cycle The “laboratory testing cycle” ( Figure 1 ) consists of all steps between the time when a clinician thinks about and orders a laboratory test and the time the appropriate patient’s sample for testing is obtained and the results of the testing are returned to the clinician (often called the “vein-to-brain” turnaround time [TAT] of test results). This cycle consists of 3 phases:  preanalytical phase, Analytical phase, Post-analytical phase:

8. Types of Laboratory samples Laboratory samples, collected from patients for laboratory analysis. samples including: Blood sample Urine sample Stool sample Seminal fluid sample Cerebrospinal fluid (CSF) sample Synovial fluid and Amniotic fluids sample s SEROUS FLUIDS: pleural, pericardial and peritoneal fluids samples Tears, salvia, sweat, cerumen, Mucus, sputum, Milk , samples , … etc. Tissue and swap samples

9. 1. Blood Samples The blood plays a big role in overall health and contains a lot of information about what may be going on in the body. Blood sample are used to: Diagnosis : Identifies conditions like anemia, infections, and leukemia. Monitoring : Tracks chronic disease management and treatment efficacy , Screening : Detects conditions like diabetes and cardiovascular diseases. Check how well organs are working, and Find out if treatment for a disease is working. Help diagnose  bleeding  or clotting disorders. Find out if  immune system  is having trouble fighting infections .

10. 1. Blood Samples Types: Whole Blood : Composition : Red blood cells (RBCs), white blood cells (WBCs), platelets, plasma (liquid portion). Whole Blood : Uses : Complete Blood Count (CBC): Evaluates overall health and detects disorders like anemia, infection, and leukemia. Blood Typing and Crossmatching: Determines blood group and compatibility for transfusions. Blood Cultures: Identifies bacterial or fungal infections in the blood.

11. 1. Blood Samples Types: Serum: Composition: Plasma without clotting factors (obtained after blood coagulation and centrifugation). Specific Uses: Biochemical Tests: Measures levels of proteins, hormones, and electrolytes (e.g., liver enzymes, kidney function tests). Serology: Detects antibodies and antigens for infectious diseases (e.g., HIV, hepatitis).

12. 1. Blood Samples Plasma: Composition: The liquid part of blood including clotting factors (obtained from anticoagulated blood). Specific Uses: Coagulation Studies: Assesses blood clotting ability (e.g., PT/INR, aPTT ). Plasma Protein Levels: Measures proteins like albumin and globulins. Buffy Coat : Composition : WBCs and platelets layered between RBCs and plasma after centrifugation. Uses : Genetic studies, molecular diagnostics.

13. 2. Urine Samples Urine is actually a “fluid biopsy” of the kidneys and can provide a fountain of information about the health of an individual. The kidneys are the only organs that can have their functional status evaluated by such a noninvasive means. In addition, because urine is an ultrafiltrate of the plasma, it can be used to evaluate and monitor body homeostasis and many metabolic disease processes. Two unique characteristics of a urine specimen account for this continued popularity: Urine is a readily available and easily collected specimen. Urine contains information , which can be obtained by inexpensive laboratory tests, about many of the body’s major metabolic functions . These characteristics fit in well with the current trends toward preventive medicine and lower medical costs .

14. 2. Urine Samples The purposes of performing a routine urinalysis are : to aid in the diagnosis of disease to screen for asymptomatic, congenital, or hereditary disease to monitor disease progression to monitor therapy effectiveness or complications. Importance of urine analysis It can detect diseases which pass unnoticed : e.g. DM, chronic UTI, … etc. Diagnosis of many renal diseases: e.g. nephrotic, nephritic syndrome, acute & chronic renal failure, multiple myeloma, … etc. Assists in the diagnosis of other diseases : e.g. Hemolytic anemia , some liver diseases, some endocrinal glands disorders, …etc.

15. 2. Urine Samples Composition: Urine is a liquid waste product composed of Primarily water, 94% and 6% solutes, ( Organic: Urea, uric acid, creatinine, urochrome, urobilinogen, some enzymes, amino acids, fatty acids, oxalic acid, COH, hormones, mucins, phenols, ammonia, etc. Inorganic: sodium, chloride, potassium, calcium, sulfates , phosphates, bicarbonates, hydrogen ions, etc. The substances found in urine can be affected by different factors such as: Dietary intake Body metabolism Other factors

16. 2. Urine Samples Types of Urine Samples: Random sample – routine: (At any time: urine analysis, urinalysis, urine ex., UE. Early morning sample (concentrated): qualitative & for UTI. In orthostatic proteinuria: before & after gets up. 24hrs sample: quantitative for chemical substances. E.g. proteins, uric acid, creatinine clearance, vanillyl mandelic acid, microalbuminuria, …etc. Spot tests: screening for some chemical substances. 2hrs afternoon: for urobilinogen & Urinary schistosomiasis Post prandial sample: for D.M.

17. 2. Urine Samples Types of Urine Samples: Midstream sample (Clean catch sample): for UTI & urine C/S. Catheterized urine: (from the catheter). Supra – pubic Aspiration (invasive): The best for UTI. Prostatitis Specimen: for prostatic infection (3 samples). Drug Specimen Collection: (chain of custody), avoid adulteration. Pediatric Specimen: clear plastic bags with hypoallergenic skin adhesive

18. 3. Stool Samples Composition : The feces consist of undigested foodstuffs (e.g., cellulose), sloughed intestinal epithelium, intestinal bacteria, gastrointestinal secretions (e.g., digestive enzymes), bile pigments, electrolytes, and water. Examination of feces provides important information that aids in the differential diagnosis of various gastrointestinal tract disorders, which range from maldigestion and malabsorption to bleeding or infestation by bacteria, viruses, or parasites. Hepatic and biliary conditions that result in decreased bile secretion, as well as pancreatic diseases that cause insufficient digestive enzymes, also are identifiable by fecal analysis. Fecal analysis is also valuable for determining the presence of increased fecal lipids (steatorrhea) and in the differential diagnosis of diarrhea.

19. 3. Stool Samples Specific Uses : Detection of gastrointestinal infections (e.g., bacteria, parasites, viruses). Fecal occult blood test (FOBT) Detects hidden blood in the stool, which can be a sign of colorectal cancer, and to screen for gastrointestinal bleeding. Fecal fat analysis (to diagnose malabsorption conditions). Evaluation of digestive health (e.g., inflammation markers). Screening For inflammatory bowel diseases (e.g., Crohn’s disease, ulcerative colitis). Monitoring: Assesses treatment effects and disease activity .

20. 4. Cerebrospinal Fluid (CSF) Samples CSF Formation Cerebrospinal fluid (CSF) is the Clear fluid containing glucose, proteins, and cells that surrounds the brain & spinal cord. The brain & spinal cord are surrounded by the meninges that consist of three layers: dura matter, arachnoid & pia matter CSF flow between the arachnoid & pia matter in an area referred to as the subarachnoid space The cerebrospinal fluid is formed mainly in the choroid plexuses Of the lateral, third, and fourth ventricles.

21. 4. Cerebrospinal Fluid (CSF) Samples Purpose of CSF Analysis To diagnose medical disorders that affect the central nervous system: Viral , fungal, parasitic and bacterial infections , such as meningitis and encephalitis . Tumors or cancers of the nervous system. Bleeding ( hemorrhage ) around the brain and spinal cord. Multiple sclerosis: an autoimmune disease that affects the myelin coating of the nerve fibers of the brain and spinal cord. Syphilis : a sexually transmitted disease. Caused by T. pallidum. Monitoring: Tracks disease progression and treatment effects.

22. 5. Seminal Fluid Samples Semen is a body fluid that is ejaculated at the time of orgasm. It contains sperms & secretion of the accessory glands : seminal vesicle , prostate & bulbourethral ( Cowper’s ) gland.

23. Indications / Reasons for Testing: Investigation of fertility & identify treatment options (surgical, medications, IVF). Post-vasectomy Identification of a fluid as semen ( forensic medicine) Artificial insemination programs – sperm donors Andrology disorders and genital tract infections 5. Seminal Fluid Samples

24. Fluid in the lung cavity It is essentially interstitial fluid of the systemic circulation It is about 3- 20 ml under normal conditions. Drained by the lymphatic system Normally it’s a clear or pale yellow fluid. Pleural effusion is an abnormal accumulation of fluid in the pleural space. The 5 major types of pleural effusion are: Transudate, Exudate, Empyema, Hemorrhagic pleural effusion or hemothorax and Chylous or chyliform effusion . Uses: Analysis of pleural fluid helps diagnose pleuritis, tuberculosis, malignancies, and heart failure. 6 . Pleural Fluid

25. Fluid in the abdominal cavity and contains water, proteins, and immune cells. Access fluid is a condition called Ascites Peritoneal effusion: Is a common complication in many diseases which may be: Transudate due to: Congestive heart failure Hypoproteinemia Nephrotic syndrome Liver cirrhosis Exudate due to: Peritoneal malignancy. infective peritonitis e.g. Tuberculous peritonitis. Pancreatic ascites. Trauma. Peritoneal fluid analysis aids in diagnosing peritonitis, malignancies. 7. Peritoneal Fluid

26. The fluid surrounding the heart Normally contains about 10 to 50 mL of a Clear, straw colored ultrafiltrate of plasma When accumulates, it can mechanically inhibit the normal action of the heart → immediate aspiration . Composition: Pericardial Fluid is Fluid from the pericardial sac around the heart, and contains Water, electrolytes, proteins, cells (white and red blood cells), and other solutes. Uses: - Diagnosis of infections (e.g., bacterial, viral, fungal). - Detection of malignancies. - Assessment of inflammation or bleeding. 8. Pericardial fluid

27. Synovial fluid, “joint fluid,” is a viscous liquid found in a fibrous joint capsule in the cavities of the movable joints . Characteristics of synovial fluid: Ultrafiltrate of plasma with hyaluronic acid and lubricating glycoproteins Viscous ( hyaluronic acid) Reduce friction between joints, providing lubrication & nutrients to the joints. Normal knee only with 3-4ml of fluid Uric acid and glucose levels in synovial fluid same as that of plasma 9. Synovial fluid

28. Indications of the analysis Helps t h e d i agn o s i s o f m a n y joint diseases (arthritis): Bleeding in the joint after a joint injury Gout and other types of arthritis Infection o r inf l am m a t i o n i n a joint S o m et i m e s , r e m o v i n g t h e fl u id can also help relieve joint pain. 9. Synovial fluid

29. It is the fluid contained inside the amniotic sac in which the embryo is free to move and protected against mechanical injury. The study of amniotic fluid is performed primarily for three reasons: (1) to enable antenatal diagnosis of genetic and congenital disorders early in fetal gestation (15 to 18 weeks), (2) to assess fetal pulmonary maturity later in the pregnancy (32 to 42 weeks), and (3) to estimate and monitor the degree of fetal distress caused by isoimmunization or infection. Amniotic fluid is similar in composition to the extracellular fluid and contains: Undissolved material from the fetal urine and respiratory secretions . Secretions from the placental membrane . C. Volume of amniotic fluid ranges 450- 1500 ml . 9. Amniotic fluid

30. D. Amniocentesis is the Trans-abdominal aspiration of fluid from the amniotic sac for biochemical and cytological analysis. E. Analysis of the amniotic fluid and cells helps in diagnosis of many intrauterine fetal diseases and abnormalities : Measurement of the lecithin/sphingomyelin (L/S) ratio indicates maturation of fetal lungs . Ratio 4 / 1 indicates mature lungs and ratio less than 4/1 indicates immature lungs. Measurement of bilirubin in amniotic fluid indicates the degree of fetal red blood cell destruction and the severity of hemolytic anemia as in Rh incompatibility . Measurement of alpha fetoprotein (a globulin produced by the fetal liver between the 6 th and 32 nd weeks of pregnancy) indicates some fetal abnormalities as neural tube defects . Cytogenetic study for the early detection of some genetic diseases such as Down’s syndrome . 9. Amniotic fluid

31. These are hypotonic solutions containing mainly Na+ and Cl- . Sweat also contains traces of urea and K+ Lysozyme , an enzyme that has an antibacterial action, is present both in sweat and tears . Composition: Water, electrolytes (mainly sodium and chloride), urea, and lactate. Uses: Diagnosis of cystic fibrosis through Measuring sweat chloride concentration. Monitoring electrolyte imbalance. Metabolic Disorders: Screening for conditions that affect sweat composition. Used mainly to diagnose cystic fibrosis in children. 10. Sweat and tears:

32. Composition : Sputum is a mixture of mucus, cellular debris, bacteria, and white blood cells produced by the lungs , fungi, and other pathogens from the respiratory tract. Specific Uses : Diagnosis: Identifies respiratory infections like tuberculosis and pneumonia. Screening: Detects cancer cells in the lungs. Evaluation: Assesses chronic conditions such as chronic obstructive pulmonary disease (COPD). 11. Sputum Samples

33. Fine Needle Aspiration (FNA): Composition: Cells from a mass or lesion. Uses: Initial diagnostic for tumors or cysts. Core Biopsy: Composition: Cylindrical tissue sample from a lesion. Uses: Detailed analysis of tumors, especially for cancer diagnosis. 12. Tissue Samples (Biopsies)

34. Excisional Biopsy: Composition: Entire lump or area of concern. Uses: Comprehensive evaluation for malignancies and large lesions. Specific Uses : Diagnosis: Identifies cancers, infections, and autoimmune diseases. Assessment: Determines the extent and stage of diseases. Monitoring: Tracks disease progression and treatment response. 12. Tissue Samples (Biopsies)

35. Composition : Water, enzymes, electrolytes, mucus, antibodies, and cells. Specific Uses : Diagnosis: Detects viral infections and certain bacteria (e.g., HIV, COVID-19). Genetic Testing: Provides DNA for genetic studies. Hormone level testing Measurement of cortisol, testosterone, estrogen levels. Drug and alcohol testing Detects the presence of drugs or their metabolites. 13. Saliva Samples

36. Types: Throat swabs Composition: Cells and secretions from the throat, are used for recovery of Streptococcus pyogenes, adenoviruses and herpes viruses, Corynebacterium diphtheriae, Mycoplasma, Chlamydia, and Candida spp. Nasopharyngeal swabs Composition: Cells and mucus from the nasal cavity, are better suited for recovery of Bordetella pertussis, Neisseria spp. and C. diphtheriae, Detects respiratory infections like influenza and COVID-19. Nasopharyngeal secretions collected by either aspiration or washing will improve recovery for Bordetella pertussis because a larger amount of material is obtained. Diagnosis: Identifies infections and pathogens. Screening: For diseases and infections. 14. Swab Samples

37. Types: Aspiration: Composition: Liquid portion containing marrow cells. Uses: Diagnoses blood disorders like leukemia and anemia. Biopsy: Composition: Solid tissue core from the bone marrow. Uses: Provides detailed information on marrow structure and cellularity. Specific Uses : Diagnosis: Identifies hematologic malignancies and disorders. Assessment: Evaluates marrow function and disease progression. 15. Bone Marrow Samples

38. Composition: Keratin, with traces of minerals, toxins, drugs, and other metabolites. Uses: Drug Testing: Detects long-term drug use or exposure. Hormone analysis. Toxicology: Identifying exposure to heavy metals and environmental toxins. Nutritional Deficiencies: Assessing deficiencies based on mineral content. 16. Hair Samples

39. Composition: nails is composed primarily of keratin, with hair containing small amounts of melanin and trace elements. Uses: Toxicology Testing: Detecting long-term exposure to heavy metals or drugs. Fungal Infections: Diagnosing fungal infections in nails. 17. Nail Samples

40. Category Definition and commonly performed tests Hematology Hematology is the science that deals with the study of blood and blood forming tissues. Lab analysis for hematology deals with examining blood for detecting abnormalities and includes areas such as blood cell counts, cellular morphology, clotting ability of blood, and identification of cell types. Erythrocyte sedimentation rate Prothrombin time Differential white blood cell count Hematocrit Hemoglobin Platelet count Red blood cell count Reticulocyte count White blood cell count

41. Category Definition and commonly performed tests Clinical Chemistry Laboratory analysis in clinical chemistry determines the amount of chemical substances present in body fluids, excreta, and tissues. For example blood, urine, and cerebrospinal fluid. The most commonly evaluated clinical chemistry is blood chemistry. Alanine aminotransferase (ALT) Albumin Alkaline phosphatase (ALP) Amylase Aspartate aminotransferase (AST) Bilirubin Blood urea nitrogen (BUN) Calcium Carbon dioxide Chloride Cholesterol Creatinine Creatinine phosphokinase (CPK) Gamma glutamyltranspeptidase Globulin Glucose Inorganic phosphorus Lactate dehydrogenase (LDH) Potassium Pyroxene Sodium Total proteins Triglycerides Triiodothyronine uptake (T3 uptake) Uric acid

42. Serology and Blood banking Blood banking is serology deal with the study of antigen/antibody reactions and assessing the presence of disease or other potential pathologic substances. ABO blood typing Anti- nuclear antibody (ANA) Antistreptolysin O (ASO) C- reactive protein (CRP) Hepatitis tests HIV test Latex Pregnancy test Rh anti- body test Rh typing Rheumatoid factor (RF) Syphilis test (VDRL, RPR)

43. Urinalysis Urinalysis is the physical, chemical, and microscopic analysis of urine. Tests for physical analysis of urine includes: Color, Appearance, and Specific Gravity. Tests included in chemical analysis are: pH, Specific gravity, Glucose, Protein, Ketones, Blood, Bilirubin, Urobilnogen, Nitrite, Leukocytes. Tests included in microscopic analysis of urine are: Red blood cells, White blood cells, Epithelial cells, Casts, Crystals Microbiology Microbiology is the scientific study of microorganisms. It includes the identification and categorization of pathogens present in specimens taken from the body (such as urine, blood, throat, sputum, wound, urethra, vagina, cerebrospinal fluid). The following are examples of infectious diseases diagnosed by identifying pathogens present in a specimen: Candidiasis Chlamydia Diphtheria Gonorrhea Meningitis Pertussis Pharyngitis Pneumonia Streptococcal sore throat Tetanus Tonsillitis Tuberculosis Urinary tract infection

44. Parasitology Parasitology deals with the detection or presence of disease producing human parasites or their eggs present in specimens taken from the body (for example stool, vagina, blood). Examples of human diseases caused by parasites include: Amebiasis Ascariasis Hookworm Malaria Pinworms Scabies Tapeworms Toxoplasmosis Trichinosis Trichomoniasis Cytology In the lab, cytology deals with the detection or presence of abnormal cells. These tests include chromosomal studies and a Pap smear. Histology Histology is the microscopic study of form and structure of various tissues that make up living organisms. Lab analysis deals with the detection of diseased tissues and includes tissue and biopsy analysis.