Pathology Concepts Quiz

Introduction to Pathology

• Lecture 1 is an introduction to pathology, cellular responses, and cellular adaptations for the Medicine and Surgery Program.

Pathology

• Pathology is the scientific study of disease, including functional and structural changes.
• It considers effects from the molecular level to the individual.

Stages of Pathology

• General pathology involves the study of the main types of disease processes like inflammation and tumors.
• Systematic pathology studies diseases of specific organs or systems, such as lung cancer.

Characteristics of Disease

• Epidemiology refers to the incidence or distribution of disease.
• Etiology refers to the cause of a disease.
• Pathogenesis refers to the mechanism of disease.
• Morphological, functional, and include clinical changes.
• Complications and sequelae are also characteristics
• Prognosis refers to the outcome of a disease.

Epidemiology

• Epidemiology involves the distribution and determinants of a disease in different populations.

Etiology

• Genetic abnormalities can cause diseases
• Environmental factors like infective agents, chemicals, radiation, and mechanical trauma can cause diseases
• Multifactorial etiology occurs when some diseases can be caused by a combination of factors.
• Some diseases have unknown causes (primary, idiopathic, or cryptogenic).
• Risk factors: sometimes exact etiology of a disease is unknown, but it is more common in people with certain traits, occupations, or habits.
• Other risk factors, like malnutrition, may facilitate the development of disease.

Pathogenesis

• Pathogenesis is the mechanism by which etiology operates to produce disease.

Morphological Changes

• A lesion is a structural abnormality seen in an organ due to disease.
• Structural changes can be detected through gross examination of organs or light/electron microscopy.

Complications and Sequelae

• Diseases may have secondary effects, such as the spread of infection or intestinal obstruction from a tumor.

Prognosis

• This describes the expected fate of a disease if it runs its natural course.
• Medical or surgical intervention can change the prognosis.

General Classification of Diseases

• Classified by pathogenesis.
• Congenital diseases can be genetic or non-genetic.
• Acquired diseases can be inflammatory, hemodynamic, growth disorders, disordered immunity, or metabolic/degenerative.

Cellular Response to Injury

• Responses to exogenous stimuli include adaptation.
• Adaptation types: atrophy, hypertrophy, hyperplasia, and metaplasia.

Reversible Injury

• Pathologic changes in a cell can be restored if the stress is removed or mild.

Irreversible Injury

• Permanent pathologic changes in a cell result in cell death.
• This occurs when stress exceeds the cell's capacity to adapt.

Hypertrophy

• Hypertrophy is an increase in the size and weight of an organ.
• This is due to to the increased size of its cells, which have synthesized more metabolic structural components to cope with increased demands.

Types of Hypertrophy

• Physiological hypertrophy occurs in a pregnant uterus due to hormone stimulation, and in muscles which adapt to a athletes demands.
• Adaptive hypertrophy: Muscle coat of hollow organs can be affected by increased intra-luminal pressure.
  • Examples include the heart.
  • Left ventricular hypertrophy can come about through aortic valve stenosis, or hypertension.
• Compensatory hypertrophy: If one of a set of paired organs is out of action, whether surgically removed or otherwise, the remaining organ undergoes hypertrophy.
  • An example is the remaining kidney, which enlarges.

Hyperplasia

• Hyperplasia is an increase in the size and weight of an organ due to an increase in the number of its cells, and it can occur in any cell type capable of division.
• Pre-cancerous.

Types of Hyperplasia

• Physiological hyperplasia: Hormonal, such as mammary glands and genitalia at puberty due to estrogen stimulation.
  • Compensatory: Bone marrow hyperplasia after hemorrhage.
• Pathological hyperplasia: Hormonal, such as endometrial hyperplasia due to estrogen stimulation, or benign prostatic hyperplasia.
  • Lymphoid: Response to antigenic stimulation.

Introduction To Medical Parasitology

• Medical parasitology delves into the parasites infecting humans and the resulting diseases.
• Commensalism: one living organism benefits while the other is unaffected.
• Parasitism: one organism benefits (parasite) at the expense and harm of the other (host)

Relationships Between Organisms and Hosts

• A parasite lives at the expense of another organism, called the host.
• The host harbors the parasite and may experience harm as a result.
• Mutualism: Both organisms benefit from the relationship.
• Symbiosis: A long-term beneficial relationship where organisms cannot live separately.

Types of Hosts

• Definitive host (D.H): The host harbors the mature stage of the parasite, where sexual reproduction occurs.
• Intermediate host (I.H): This host harbors immature or larval stages, or non-sexually reproducing forms.
• Reservoir host (R.H): An animal host harbors the mature stage, serving as a source of infection for humans, and maintains the parasite in nature.
• Vector: This is an arthropod which transmit parasites between hosts.

Types of Parasites

• Accidental parasite: One that infects an unusual host.
• Facultative parasite: An organism that can live as a parasite or as a free-living form.
• Obligatory parasite: Cannot survive without a host, entirely dependent upon a host for its survival.
• Ectoparasite: Parasite living on the skin (infestation).
• Endoparasite: Parasite living inside a part of the host (infection); most helminthic parasites causing human disease are endoparasites.

Parasite Transmission

• Hosts: D.H, I.H, R.H, and vectors if present.
• Transmission: I.S (Infective stage) and D.S (Diagnostic stage).
• Habitat.
• Mode of infection.

Terms Used in Parasitology

• Habitat: This the final organ or site where the parasite lives in the definitive host.
• Infective stage (I.S): This is the stage by which the infection takes place.
• Diagnostic stage (D.S): Stage by which a parasitic infection can be diagnosed.
• Carrier: This Host has parasite with minimal symptoms but is infective to others.
• Zoonosis: Transmission of animal infection to humans via intermediate host.
• Endemicity: Steady parasitic infection level in a population with certain resistance.
• Epidemicity: Fulminating parasitic disease outbreak from a new parasite in population.

Routes of Parasite Transmission

• Direct contact through the skin.
• Ingestion of contaminated food or water containing the infective stage (fecal-oral route).
• Inhalation of dust carrying the infective stage.
• Penetration of the skin due to contact with infected soil or water.
• Congenital: via transplacental or transmammary routes.
• Sexual contact.
• Autoinfection: either external or internal.
• Vectors, through bite or feces of infected vector, or swallowing/crushing the vector.
• Blood transfusion or iatrogenic transmission (contaminated syringes).
• Organ transplantation.
• Nosocomial after admission to the hospital.

Parasites Life Cycles

• Direct life cycle: This requires a single host for development (e.g., Ancylostoma duodenale).
• Indirect life cycle involves 2 or more host species (e.g., Heterophyes heterophyes).

Pathogenesis of Parasitic Infection

• Occurs through mechanical obstruction, traumatic invasion, toxin production, tissue damage, or cellular destruction.
• Immune stimulation :May cause symptoms and/ or encapsulation of a granuloma.

Clinical Manifestations of Parasitic Infections

• Symptoms may range from asymptomatic to severe symptoms that result in death.
• Observed symptoms include diarrhea, abdominal pain, and abdominal cramping.
• Other symptoms include elephantiasis in filariasis, anemia, , bowel obstruction, edoema, skin lesions, and blindness.

Immunity Response

• Like other infectious agents, parasites elicit immune responses.
• Protection against parasitic infections is often less effective than protection against bacterial or viral infections.

Immune Response to Helminths

• IgE and eosinophils are key in eliminating helminths.
• Phagocytosis is also involved, to an extended size to eliminate.

Defense Against Helminthic Infections

• Defense is mediated by TH2 cells, IgE, mast cells, and eosinophils during ADCC.
• Infections tend to be chronic due to weak innate immunity and parasite’s ability to evade or resist the immune system.

Immune Response to Protozoa

• Cell-mediated immunity destroys protozoa that live within host cells.
• Principal innate immune response to protozoa is phagocytosis
• Many of these can resist phagocytic killing, or even repliate.

Immune Evasion of Parasites

• Sequestration: Can hide away from the immune systems by invading the brain.
• Parasites shedding :They surface Antigens as the T-cells, which limits the reach of most antibodies.
• Antigenic variation: changing of their epitopes through mutation.
• Molecular Mimicry: The presences of a host (or host-like) molecular.
• Immune suppression: Inhibiting the Suppression of the bone marrow

Anti-Parasitic Vaccine Development

• No effective vaccine against parasites.
• Due to complex life cycles, antigenic variation, difficulty in making new protective antigens, and the limitations of available animal model to test the drug.
• However anti-parasite experimentation under certain conditions has shown a some promise against Malaria, Bilharziasis, and Leishmaniasis.

Diagnosis of Parasitic Infections

• History
• Clinical diagnosis of the related parasitic infection.
• Laboratory diagnosis (3 types)

3 Types of Medical Examinations

• Direct: Microscopic examination, culture of stool or soil, animal inoculations, and detection of parasitic coproantigens.
• The following specimens are required: stool, blood, cerebrospinal fluid (CSF), tissue aspirates, urine, sputum, and genital specimens.

Microscope

• The microscope is an important piece of laboratory equipment and helps one understand the direct diagnostic tests
• Relevant information include: the objective, the ocular, source of light, revolving nosepiece.

More Information

• Trophozoites Entamoeba - Important in Dysentry.

Indirect Diagnosis (Types of Diagnostic tests)

• Used when parasites are present in tissues or in cases of chronic infection.
• Intradermal test: Intradermal injection (As control)
• Detection of antibodies : Fixation Test.
• Detection circulating Antigens: ELISA, and indirect immunofluorescent antibody test.

Other Imaging Related tests

• Ultrasound
• Radiology (CT Scan and MRI)

Methods for Diagnostic Results

• Molecular methods such as PCR (Polymerase Chain Reaction)

Other Symptoms Related tests

• Hematology and Biochemical

Treatment

4 categories: Treatment with the appropriate medical medication, surgery, vitamin supplements, treatment of complications and transfusions.

Prevention and Control

5 ways to prevent: Inform the patient about the mode of infection, control the destruction, hygiene products, cleaning of products and water supplies, washing of insecticides.

Classification of Medical Parasites

• Parasitology is classified into three main groups: protozology, helminthology, and entomology.
• Protozology: Study of Protozoa
  • Proto = animals
• Helminthology: Study of helminth
  • Helminth = worm
• Entomology: study of arthropods

Nomenclature of Parasites (Taxonomy)

• Genus- Begins with a capital letter
• Species - name begins with small letter, Fasicola hepatica or F.hepatica, is written in italics.

Classifications of Helminths

• Platyhelminths and flatworms, Nematelminths and Round worms
• Under Platyhelminthes classification includes trematoda Flukes and Cestoda "tapeworms".

General Characteristics of Platyhelminthes

• The Class contains trematoda Flukes helmiths
• Body structure structure.
• The structure shape and body contains cuticle for protection. and consists of the structure.
• Oral (Anterior Side of Mouth) (Also Ventral and Genital)

Digestive System Compositions

• Composed of anterior and surrounded by the oral sphincter
• contains esophagus with muscular section and can bisect.
• Contains two (anus)

Other Systems

• Excretory contains symmetrical flame cells.
• Genital is Hermaphrodite except for schistosoma.

Other facts

• Eggs structure are operculated apart for eggs
• The passes contain cycle from worms can sexually cycle.
• miracidium develops to reach certain stage.

Characteristics of Trematodes Cercaria

• Consists of bodies
• the shape of tile are divided based on shape.

Classification of Trematode Habitat

• Hepatic flukes
• Intestinal Flukes, and lung fluke
• Schistoseoma Mansoni and haemotobium

Cestoda (Tapeworms)

• Flat worms, Ribbon-like worms.
• Length ranges from MM.
• Scolex.

Classifications of Helmiths (Continued)

• N.B.- Cestodes has NO BODY CAVITY, nutrition is absoprbed via tegument
• Class consists or Tape worm infections.
• Includes the cyclophillidae

Tapeworms

• Compared with Cyclophellidea, is very few meters
• contains pseudo grooves vs the true 4 suckers.
• Mass behind the ovary for vellitine.

General Charactitics.

• Contains systems:
• Contains a male reproductive system
• Contain uterine.

Cestodes Classifications

• Testes and Uterine stalks serve to connect
• Includes Vagina and seminal vesicle, used to identify structure

1. NTA
2. NATIONAL.
3. TRAINING ACADEMY
4. الأكاديمية الوطنية للتنديب

Taenia

• Mature sections serve to help with diagnosis of issues with segments.

Cestodes Classifications for Animals

• 4 aspects

1. Vas Deferens serves to deliver structure.
2. Includes the collecting duct.
3. The cirrus (Uterine section) includes Ovaries.

Microbiology

Learning Objectives

• Definitions related to microbiology
• Members of the microbial world
• Types of cells
• Differences between prokaryotic and eukaryotic cells
• Classification of bacteria

Definitions

• Microbiology is the study of micro-organisms.
• Micro-organisms are any organism too small to see with the naked eye.

Members of the Microbial World

• Acellular (non-cellular) and cellular.
• Acellular is viruses.
• Cellular are prokaryotic bacteria and archaea are examples.
• algae, fungi and protists are types of eukaryotic microorganisms

Types of Cells

• Prokaryotic (Pro = before): The nucleus does not have a true kernel.
• Eukaryotic (Eu= true): The nucleus (kernel) is true.

Differences Between Eukaryotic and Prokaryotic Cells

• Size: Eukaryotes are generally much larger
• Eukaryotes true nucleus, consisting of a nuclear membrane and nucleoli.
• Prokaryotes have membrane enclosed organelles but not a membrane.
• Eukaryotes have examples of Lysosomes
• Eukaryotes (Internal Membranes) or Mitochondiral Chloroplasts.

More Differences

• Eukayotes Contains carbohydrates vs. Prokaryotes. Cytoskeletal vs Non Cytosketetal
• Smaller size (70) with Single cellular chromosome(703)

Bacteria information

• Categorized by shape, ability to form spores, nutritional source, results after a Gram stain, method for energy production, pathogenicity, or genotypic classification.

Morphological Classification of Bacteria

• Filamentous, Gram +ve cocci, Gram –ve cocci, Gram +ve bacilli,
• Gram –ve bacilli and Microscopic Classification

Pathogenicity Classification of Bacteria

• Pathogens: can spread disease.
• Non-pathogens: do not cause infections or parasitic problems, (lactobacilli) and (Commensals) .

Genotypic Classification in bacteria

• Higher classification: PCR and 16s Ribosomal RNA analysis
• Others include: DNA and finger printing

Bacterial Cell Structure

General Structure

• Outer Structure, Flagella
• Contains envelope and Cytoplasmic Membrane.
• Cell wall
• Mesosomes, inclusion (granules)

Essential Components

• Essential vs. Non essential

Cytoplasm

• Membranes, Nucleoid vs capsure
• Cytoplasmic/ Flagela

Structure of Cell wall

• Major Part: Peptidoglycan
• The wall structure is rigid

Gram +ve and Gram -ve

• Gram contains a high amount of of cell mass
• gram is Lipid membrane.
• Contains any of the the Lipid

Other Facts

• Functions A-3-D
• Provides cell and different shapes
• Detects Stain.

Cell Wall Deficiency in Cell Bacteria

• Bacteria vs micr
• Lost as a loss. Is easy take.

Cell Membranes

• Proteins and. Phosphates
• osmotic sensitive
• Outer Cell
• Inner Cell

Other information needed to know

• Selective, permabilility to serve as permabiltiy factor
• Plays a factor helps with reproduction
• Has multiple
• Secretion of hydro
• Chemotactic with Bacteria
• Increase of cytopasmitc.
• Site for enzymes.
• This cell wall is easy to find.

Cell

• Has a large layer of cell mass but it's made of material.
• It consist of material's, (glycoprotien
• It appears to be ring shaped.

Funciton in bactiera

• Serves the bacteria, againist disticaation
• Used in bacterial components

Appendages

• Includes filament structure
• The pilin is
• Has different structures for pilin and
• Medial (Adherenre)
• Acts as a
• ribm and structure: D structure

Structrues

• Ribm
• The structure
• 3 - intern 1 2 3 4. -Inclusiom

4. 20 nm. In deimater

Functions

Polyisbone: Aggri

Test your knowledge of pathology concepts. Questions cover systematic pathology, disease characteristics, pathogenesis, structural abnormalities, disease consequences, and disease prognosis. Learn more about how diseases develop and affect the body.