UNIT 1st INTRODUCTION OF PATHOLOGY FOR NURSES

The study of pathology will prepare the nurses to understand how the disease started, what was the main cause of disease process, how diseases are diagnosed and what changes may be expected at cellular, tissue and organ level during the illness.

1. INTRODUCTION OF PATHOLOGY Mr.Pawas Netawat Medical surgical nursing HOD (CARDIO)

2. CONTENTS Importance of the study of pathology Definition of terms Methods and techniques Cellular and Tissue changes Infiltration and regeneration Inflammations and Infections Wound healing Vascular changes Cellular growth, Neoplasm Normal and cancer cell Benign and Malignant growths In situ carcinoma Disturbance of fluid and electrolyte imbalance

3. PATHOLOGY The word Pathology’ is derived from two Greek words— pathos (meaning suffering) logos (meaning study). Pathology is, thus, scientific study of changes in the structure and function of the body in disease. pathology consists of the abnormalities in normal anatomy (including histology) and normal physiology owing to disease.

4. IMPORTANCE OF STUDY  OF PATHOLOGY General knowledge of how disease are caused. • General patterns and classification of diseases • Evolution of disease from its causes to clinical presentation • The signs and symptoms of disease • Nature, spread and precautions to prevent common diseases • Know the different disciplines that make up pathology • Better understand the patient and his disease.

5. IMPORTANCE OF THE STUDY OF PATHOLOGY FOR NURSES 1.The study of pathology will prepare the nurses to understand how the disease started, what was the main cause of disease process, how diseases are diagnosed and what changes may be expected at cellular, tissue and organ level during the illness .   2 . To understand the patterns and classification of diseases Understanding the causes of disease: The knowledge of pathology will equip the nurses with following essential information related to etiology and pathogenesis of diseases:   3. To understand the etiology and pathophysiological mechanisms, which underlie a disease process Understanding the basic nature of diseases such as inflammatory, degenerative, hemodynamic, infective, autoimmune and neoplastic   4. Knowledge about   Pathology serves as a foundation for nurses to understand the pathophysiology of a disease, so that nursing care can be planned more efficiently

6. IMPORTANCE OF THE STUDY OF PATHOLOGY FOR NURSES 5.To correlate the clinical features with the structural and functional pathological alterations in the organs due to the disease process.   6.To appraise the evolution of disease from its causes to the clinical presentation including signs and symptoms of diseases.   7.To understand the morphological changes, which take place in the body during various disease processes.   8.Progression of the Disease: The knowledge of pathology helps the nurses to understand the basic structural and functional changes that occur in tissues, organs and the body as a whole. Furthermore, knowledge of pathology helps the nurses:  

7. DEFINITION OF TERMS Accession number:  A unique case number assigned to each specimen sample to be analyzed. Actinic:  Related to sun-exposure. Anatomic Pathology:  General term for the area of pathology that deals with the gross and microscopic analysis of organs, tissues, and cells, which includes surgical pathology, cytopathology , and autopsy. Autopsy:  Postmortem evaluation of a body to determine the cause and manner of death. Biopsy:  Removal of cells or tissues from the body for pathological examination. Blocks:  Hardened tissues encased in wax blocks that are cut to produce glass microscopic slides. Carcinoma:  A malignant tumor composed of “epithelial” cells, which can be seen in almost any body location.

8. DEFINITION OF TERMS Clinical Pathology:  A group of practice areas in laboratory medicine that is concerned with diagnosing disease based on the analysis of body fluids.  Core Biopsy:  A biopsy in which a cylindrical sample of tissue is obtained (as from a kidney or breast) by a hollow needle. Cyst:  A sac or pouch containing fluid or other materials that is encased by a tissue membrane. Cytogenetics :  The study of chromosome-related structures. Cytology:  The study of individual cells with the microscope. Cytopathology :  A subspecialty of anatomic pathology that focuses on the diagnosis of diseased cells in specimens derived from body fluids or aspirated tissue. Dermatology:  The branch of medicine that deals with the skin and diseases affecting the skin

9. DEFINITION OF TERMS Dermatopathology :  The subspecialty of anatomic pathology which deals with skin diseases. Diagnosis:  Identification of a specific disease process by a physician. Dysplastic:  Structurally-abnormal. Effusion:  An abnormal collection of fluid in one or more of the body spaces. Ellipse:  An almond-shaped portion of surgically-removed skin, usually with an abnormal area in its center. Examination (of tissue):  The process of analysis, identification, evaluation, interpretation, and review of specifically prepared slides by a pathologist. Excision:  Surgical removal of tissue with a scalpel. Exfoliative Cytology:  The microscopic analysis of cells that are shed into body cavities. Fine Needle Aspiration (FNA):  An alternative procedure to formal surgery for obtaining biopsies, in which cells are removed by drawing them under vacuum pressure through a fine needle.

10. DEFINITION OF TERMS Flow Cytometry :  Analysis of cells in fluid samples using special light sources and detectors.  Fluorescent In Situ Hybridization (FISH):  A special cytogenetic procedure in molecular pathology to identify specific nucleic acid sequences in cellular nuclei. Gastrointestinal (GI) & Liver Pathology:  Subspecialties in anatomic pathology that focus on diseases in the digestive tract and liver. Gross Description:  An examination based on a description of material that is visible to the naked eye. Gynecological Pathology:  A subspecialty area of anatomic pathology that focuses on diseases of the female genital tract (breast, uterus, fallopian tubes, ovaries, vagina, and vulva). H&E:  An abbreviation for hematoxylin and eosin stains, common biological dyes that give tissue elements distinct colors.  These are most often pink, blue, red, and purple. Hematopathology :  A subspecialty area of clinical pathology involving the study of diseases of the blood cells, bone marrow, spleen, and lymph nodes.

11. DEFINITION OF TERMS Histology:  A branch of anatomy that deals with the minute structure of animal and plant tissues as discernible with the microscope Immunohistochemistry :  A microscopic method for localizing specific proteins in tissues through the use of antibodies that are labeled with biological dyes.  Inflammatory:  A term concerning diseases that are caused by white blood cells which abnormally enter various tissues. Keratosis :  A benign growth of cells on the skin surface. Lesion:  An abnormality in tissue that is seen with the naked eye or in x-ray studies, or felt by the patient or a physician. Leukemia:  A malignant proliferation of white blood cells that originate in the bone marrow and circulate in the bloodstream.

12. DEFINITION OF TERMS Lichenoid :  Pertaining to a particular linear arrangement of inflammatory cells under the surface of the skin. Lumpectomy:  A common procedure to remove a mass from a male or female breast. Lymphoma:  A malignant proliferation of lymphocytes, which are cells involved in immune functions. Macroscopic:  An examination based on material that is visible to the naked eye. Margins:  Cuffs of healthy or normal tissue on either side of a disease (usually a tumor). Malignant:  Tending to become worse and end in death or having the properties of anaplasia , invasiveness, and metastasis; said of tumors. Mass:  A localized swelling in tissue which may or may not represent a tumor (neoplasm; see below). Mastectomy:  Medical term for the partial or complete surgical removal of a breast.

13. DEFINITION OF TERMS Melanoma:  A malignant proliferation of pigment-producing cells in the skin or other organs. Microscopic:  Visible only with a microscope and not with the naked eye. Microtome:  A device with a sharp blade, used in the laboratory for cutting tissues so that they can be affixed to glass slides and examined with a microscope after staining with biological dyes. Mole:  A commonly used term for a growth on the skin, which may or may not contain pigment. Molecular Pathology:  A field in pathology that combines aspects of clinical and anatomic pathology, with a focus on molecular cell components. Needle Biospy :  Any of several methods (as fine needle aspiration or core biopsy) for obtaining a sample of cells or tissue by inserting a hollow needle through the skin and withdrawing the sample from the tissue or organ to be examined

14. DEFINITION OF TERMS Neoplasm:  An independently-growing mass of cells in the skin or elsewhere, which may be benign or malignant.  Neoplasms also are commonly called “masses” or “tumors.” Neuropathology:  A subspecialty area of anatomic pathology that concerns diseases of the central nervous system, muscles, and nerves. Nevus:  A growth on the skin, which is often pigmented (colored). Pap Smear:  A screening test procedure named after pathologist George Papanicolaou (1883 – 1962) in which cells from a woman’s cervix (uterus) are examined microscopically for abnormalities. Pathologist:  A doctor who identifies diseases by studying cells and tissues under a microscope. Pathology:  The scientific study of the nature of disease and its causes, processes, development, and consequences. Pathology Report:  A formal document containing the diagnostic findings of a pathologist, pertaining to a particular biopsy specimen. 

15. DEFINITION OF TERMS Pediatric Pathology:  A subspecialty area of pathology concentrating on diseases of infants & children. Polyp:  A specific type of abnormal growth on the skin or on mucous membranes, which projects above the surfaces of those tissues. Prognosis:  An informed estimate of the probable course and biological behavior of a disease process. Psoriasiform : Resembling the clinical or microscopic image of psoriasis. Renal Pathology:  A subspecialty of anatomic pathology with a focus on kidney diseases. Requisition:  A formal request for laboratory services containing relevant information on a particular patient, the specimen type, and the referring physician. Sarcoma:  A malignant proliferation of connective-tissue cells. Slides:  A general term for thin sheets of glass on which tissue specimens are placed for microscopic analysis. 

16. DEFINITION OF TERMS Specimen:  A small part of the human body—either tissue or liquid– that serves as a sample for pathologic evaluation.  Spongiotic :  A disease in which excess fluid is seen in the surface layer (epidermis) of the skin. Surgical Pathology:  A subspecialty area of anatomic pathology which focuses on the evaluation of any tissue that is removed by surgical means

17. METHODS AND TECHNIQUES A. Histopathological techniques   Histopathological examination studies  tissues under the microscope. During this study, the pathologist looks for abnormal structures in the tissue.   Tissues for histopathological examination are obtained by biopsy.  Biopsy is a tissue sample from a living person to identify the disease.  Biopsy can be either incisional or excisional .    Once the tissue is removed from the patient, it has to be immediately fixed by putting it into adequate amount of 10% Formaldehyde (10% formalin) before sending it to the pathologist. The purpose of fixation is:

18. HISTOPATHOLOGICAL TECHNIQUES 1.  to prevent autolysis and bacterial decomposition and putrefaction  2.  to coagulate the tissue to prevent loss of easily diffusible substances 3 .  to fortify the tissue against the deleterious effects of the various stages in the preparation of sections and tissue processing.  4 .  to leave the tissues in a condition which facilitates differential staining with dyes and other reagents.  5.  Once the tissue arrives at the pathology department, the pathologist will exam it macroscopically (i.e. naked-eye examination of tissues).

19. HISTOPATHOLOGICAL TECHNIQUES Then the tissue is processed to make it ready for microscopic examination. The whole purpose of the tissue processing is to prepare a very thin tissue (i.e. five to seven μm or one cell thick tissue) which can be clearly seen under the microscope. The tissue is processed by putting it into different chemicals. It is then impregnated (embedded) in paraffin, sectioned (cut) into thin slices, & is finally stained. The stains can be Hematoxylin /Eosin stain or special stains  such as PAS, Immunohistochemistry , etc..

20. HISTOPATHOLOGICAL TECHNIQUES The Hematoxylin /Eosin stain is usually abbreviated as H&E stain. The H&E stain is routinely used. It gives the nucleus a blue color & the cytoplasm & the extracellular matrix a pinkish color. Then the pathologist will look for abnormal structures in the tissue. And based on this abnormal morphology he/she will make the diagnosis. Histopathology is usually the gold standard for pathologic diagnosis. 

21. B . CYTOPATHOLOGIC TECHNIQUES Cytopathology is the study of cells from various body sites to determine the cause or nature of disease.  Applications of cytopathology :  The main applications of cytology include the following:

22. CYTOPATHOLOGIC TECHNIQUES 1.  Screening for the early detection of asymptomatic cancer For example, the examination of scrapings from cervix for early detection and prevention of cervical cancer.    2. Diagnosis of symptomatic cancer Cytopathology may be used alone or in conjunction with other modalities to diagnose tumors revealed by physical or radiological examinations.    It can be used in the diagnosis of cysts, inflammatory conditions and infections of various organs. 

23. CYTOPATHOLOGIC TECHNIQUES 3. Surveillance of patients treated for cancer  For some types of cancers, cytology is the most feasible method of surveillance to detect recurrence. The best example is periodic urine cytology to monitor the recurrence of cancer of the urinary tract. Advantages of cytologic examination Compared to histopathological technique it is cheap, takes less time and needs no anesthesia to take specimens. Therefore, it is appropriate for developing countries with limited resources like Ethiopia. In addition, it is complementary to histopathological examination. Cytopathologic methods    There are different cytopathologic methods including:

24. FINE-NEEDLE ASPIRATION CYTOLOGY (FNAC) In FNAC, cells are obtained by aspirating the diseased organ using a very thin needle under negative pressure. Virtually any organ or tissue can be sampled by fine-needle aspiration. The aspirated cells are then stained & are studied under the microscope. Superficial organs (e.g. thyroid, breast, lymph nodes, skin and soft tissues) can be easily aspirated.  Deep organs, such as the lung, mediastinum ,  liver, pancreas, kidney, adrenal gland, and retroperitoneum are aspirated with guidance by fluoroscopy, ultrasound or CT scan. FNAC is cheap, fast, & accurate in diagnosing many diseases.

25. 2 . EXFOLIATIVE CYTOLOGY Refers to the examination of cells that are shed spontaneously into body fluids or secretions. Examples include sputum, cerebrospinal fluid, urine, effusions in body cavities (pleura, pericardium, peritoneum), nipple discharge and vaginal discharge.

26. 3. ABRASIVE CYTOLOGY Refers to methods by which cells are dislodged  by various tools from body surfaces (skin, mucous membranes, and serous membranes). E.g. preparation of cervical smears with a spatula or a small brush to detect cancer of the uterine cervix at early stages. Such cervical smears, also called Pap smears, can significantly reduce the mortality from cervical cancer. Cervical cancer is the most common cancer in Ethiopian women.  

27. Hematological examination This is a method by which abnormalities of the cells of the blood and their precursors in the bone marrow are investigated to diagnose the different kinds of anemia & leukemia . Immunohistochemistry This is a method is used to detect a specific antigen in the tissue in order to identify the type of disease.  Microbiological examination   This is a method by which body fluids, excised tissue, etc. are examined by microscopical , cultural and serological techniques to identify micro-organisms responsible for many diseases.

28. Biochemical examination  This is a method by which the metabolic disturbances of disease are investigated by assay of various normal and abnormal compounds in the blood, urine, etc. Clinical genetics ( cytogenetics ) This is a method in which inherited chromosomal abnormalities in the germ cells or acquired chromosomal abnormalities in somatic cells are investigated using the techniques of molecular biology.  Molecular techniques   Different molecular techniques such as fluorescent in situ hybridization, Southern blot, etc... can be used to detect genetic diseases.

29. Autopsy Autopsy is examination of the dead body to identify the cause of death. This can be for forensic or clinical purposes. The relative importance of each of the above disciplines to our understanding of disease varies for different types of diseases. For example, in diabetes mellitus, biochemical investigation provides the best means of diagnosis and is of greatest value in the control of the disease. Whereas in the diagnosis of tumors, FNAC & histopathology contribute much. However, for most diseases, diagnosis is based on a combination of pathological investigations.

30. CELLULAR AND TISSUE CHANGE ATROPHY- Cellular atrophy is a decrease in cell size. If enough cells in an organ undergo atrophy the entire organ will decrease in size.    HYPERTROPHY -Cellular hypertrophy is an increase in cell size and volume. If enough cells of an organ hypertrophy the whole organ will increase in size. Hypertrophy may involve an increase in intracellular  protein  as well as  cytosol  (intracellular fluid) and other cytoplasmic components.

31.   HYPERPLASIA -is an increase in the number of cells .  It is the result of increased cell  mitosis  or division (also referred to as  cell proliferation ). The two types of physiologic hyperplasia are  compensatory  and  hormonal .   METAPLASIA- occurs when a cell of a certain type is replaced by another cell type, which may be less differentiated. It is a reversible process thought to be caused by stem cell reprogramming.   DYSPLASIA- refers to abnormal changes in cellular shape, size, and/or organization. Dysplasia is not considered a true adaptation; rather, it is thought to be related to hyperplasia and is sometimes called "atypical hyperplasia"

32. INFILTRATION is the diffusion or accumulation of substances not normal to it or in amounts in excess of the normal. The material collected in those tissues or cells is called infiltration. CAUSES Infiltration may be caused by: Puncture of distal vein wall during venipuncture Puncture of any portion of the vein wall by mechanical friction from the catheter/needle cannula Dislodgement of the catheter/needle cannula from the intima of the vein which may be a result of a poorly secured IV device or inappropriate choice of venous site to puncture. Improper cannula size or excessive delivery rate of the fluid  

33. REGENERATION is the process of renewal, restoration, and tissue growth that makes  genomes ,  cells ,  organisms , and  ecosystems   resilient  to natural fluctuations or events that cause disturbance or damage.

34. INFLAMMATION Inflammation is defined  as the local response of living mammalian tissues to injury due to any agent.It is a body defence reaction in order to eliminate or limit the spread of injurious agent as well as to remove the consequent necrosed cells and tissues CAUSES OF INFLAMMATION:-   1.Physical agents- heat,cold,radiation,mechanical trauma. 2.Chemical agents-organic & inorganic poisons. 3.Infective agents- bacteria,viruses & their toxins 4.Immunological agents-cell mediated & antigen-anybody reactions.  

35. INFECTION is the invasion of a host organism's bodily tissues by disease-causing organisms, their multiplication, and the reaction of host tissues to these organisms and the toxins they produce. Infections are caused by microorganisms such as viruses, prions , bacteria, and Viroids , and larger organisms like parasites and fungi.

36. CAUSATIVE AGENTS EFFECTING   Prions Helminths Protozoa Fungi Viruses Bacteria HUMANS  

37. WOUND HEALING  refers to a living organism's replacement of destroyed or damaged tissue by newly produced tissue STAGES 1.Hemostasis   (blood clotting):  Within the first few minutes of injury,  platelets  in the blood begin to stick to the injured site. 2. Inflammation:  During this phase, damaged and dead cells are cleared out, along with bacteria and other pathogens or debris.  3. Proliferation (growth of new tissue):  In this phase,  angiogenesis ,  collagen  deposition,  granulation tissue  formation, epithelialization , and wound contraction occur. 4. Maturation (remodeling):  During maturation and remodeling, collagen is realigned along tension lines, and cells that are no longer needed are removed by programmed cell death, or  apoptosis .

38. VASCULAR DISEASE is a class of diseases of the vessels of the  circulatory system  in the  body , including  blood vessels  – the  arteries  and  veins , and the  lymphatic vessels . Vascular disease is a subgroup of  cardiovascular disease . Disorders in this vast network of blood and lymph vessels can cause a range of health problems that can sometimes become severe, and fatal .

39. VASCULAR DISEASE Venous disease Phlebitis Venous insufficiency Venous thrombosis Portal hypertension Vascular anomalies Arterial disease Lymphatic disease

40. NORMAL AND CANCER CELL

41. BENIGN AND MALIGNANT GROWTHS

42. CARCINOMA IN SITU The term carcinoma in situ is a term used to define and describe a cancer that is only present in the cells where it started and has not spread to any nearby tissues. Carcinoma in situ is the earliest stage of a cancer, and is, at this stage, considered "non-invasive." With regard to staging, carcinoma in situ is considered stage 0 cancer. Stage 1 to stage 4 are all considered "invasive" cancers, as they have spread beyond something called the "basement" membrane in tissues. When cancers are found at this stage, they should theoretically be 100 percent curable.

43. DISTURBANCE OF FLUID AND ELECTROLYTE IMBALANCE Fluid and electrolyte disorders are among the most common clinical problems encountered in the setting of intensive care. Critical disorders such as severe burns, trauma, sepsis, brain damage, and heart failure lead to disturbances in fluid and electrolyte homeostasis. 

44. CAUSES Fatigue Fast or irregular heartbeat Numbness and tingling Confusion Muscle weakness and cramping Headaches Convulsions