Introduction to Parasitology
45 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Which of the following is NOT a type of protozoan?

  • Sporozoa
  • Ciliates
  • Flagellates
  • Nematodes (correct)

All protozoa have a short generation time, which allows for rapid reproduction.

True (A)

What is the primary mode of locomotion for flagellates?

Flagella

The ______ is a type of helminth that has a long, flat, ribbon-like body.

<p>Cestode (Tapeworm)</p> Signup and view all the answers

Match the following protozoan types with their defining characteristics:

<p>Flagellates = Possess flagella for locomotion Sporozoa = Produce spore-like oocysts Ciliates = Have hair-like cilia for locomotion</p> Signup and view all the answers

Which of these protozoans is known to cause intestinal infections?

<p>Giardia lamblia (B)</p> Signup and view all the answers

Helminths can multiply in humans after reaching their adult stage.

<p>False (B)</p> Signup and view all the answers

Name one example of a trematode.

<p>Fasciola</p> Signup and view all the answers

What is the preferred time for specimen collection for certain tests?

<p>Early morning (B)</p> Signup and view all the answers

Tissue biopsy is performed for patients suspected of cutaneous parasitic infections to check for Entamoeba gingivalis.

<p>False (B)</p> Signup and view all the answers

What type of fluid is collected during a spinal tap (CSF) for examination?

<p>Cerebrospinal fluid</p> Signup and view all the answers

Wuchereria bancrofti and Brugia malayi exhibit a nocturnal periodicity, so samples should be collected after _____ pm.

<p>10</p> Signup and view all the answers

Match the following tests with their correct specimen types:

<p>Scrapping of the mouth = Examine for Entamoeba gingivalis and Trichomonas tenax Nasal discharge = Examine for Naegleria fowleri Blood smear = Recovery of Plasmodium species Urethral discharge = Presence of Trichomonas vaginalis</p> Signup and view all the answers

What is the primary purpose of a fecal exam or O&P test?

<p>To find parasites causing gastrointestinal symptoms (D)</p> Signup and view all the answers

Specimens for parasitic examination should be transported to the laboratory without delay.

<p>True (A)</p> Signup and view all the answers

What is the primary focus of medical parasitology?

<p>The science of parasites that infect humans (B)</p> Signup and view all the answers

What action should be taken if a patient has started antibiotic therapy?

<p>Do not collect stool specimens until 5-7 days after therapy completion.</p> Signup and view all the answers

A facultative parasite is one that must always live as a parasite.

<p>False (B)</p> Signup and view all the answers

The ______ test is commonly used for the recovery of Enterobius vermicularis (pinworm) eggs.

<p>scotch tape</p> Signup and view all the answers

What term describes a host that carries sexually mature parasites?

<p>Definitive host</p> Signup and view all the answers

Match the following parasites with their recovery methods:

<p>Enterobius vermicularis = Scotch tape test Entamoeba histolytica = Sigmoidoscopy Cryptosporidium parvum = Sigmoidoscopy Helminths = Stool test</p> Signup and view all the answers

What is recommended for collecting stool specimens to minimize contamination?

<p>Collect in a clean, wide-mouthed container (D)</p> Signup and view all the answers

A parasite that lives inside the body of its host is known as an ______.

<p>endoparasite</p> Signup and view all the answers

It is acceptable to collect stool specimens after radiologic procedures.

<p>False (B)</p> Signup and view all the answers

Which of the following defines a pathogen?

<p>A parasite capable of producing disease (D)</p> Signup and view all the answers

How many consecutive specimens should ideally be collected for pinworm infection before considering the patient infection-free?

<p>At least 4</p> Signup and view all the answers

Compromised hosts have effective normal defense mechanisms.

<p>False (B)</p> Signup and view all the answers

Match the types of parasitic relationships with their definitions:

<p>Obligate parasites = Completely dependent on the host Ectoparasites = Live on the surface of the host Commensal = Derives benefit without harming or helping Paratenic host = Transporting agent without development</p> Signup and view all the answers

The presence of arthropods on the skin of the host is referred to as ______.

<p>infestation</p> Signup and view all the answers

What is the most common portal of entry for parasites?

<p>Through the mouth (D)</p> Signup and view all the answers

Trichomonas vaginalis is transmitted through sexual contact.

<p>True (A)</p> Signup and view all the answers

Name one way through which congenital infection can occur.

<p>From mother to fetus through the placenta.</p> Signup and view all the answers

Airborne eggs of E. ______ may be inhaled into the posterior pharynx leading to infection.

<p>vermicularis</p> Signup and view all the answers

Match the following transmission methods with their associated parasites:

<p>Skin penetration = Hookworm Contaminated food = E.histolytica Transfusion of blood = Malaria Sexual contact = Trichomonas vaginalis</p> Signup and view all the answers

Which of the following modes of transmission involves contaminated fingers or utensils?

<p>Mouth (C)</p> Signup and view all the answers

Iatrogenic infections can occur due to the use of contaminated syringes.

<p>True (A)</p> Signup and view all the answers

What type of damage can migration of helminths to the lungs cause?

<p>Traumatic damage of the pulmonary capillaries.</p> Signup and view all the answers

Which specimen type can be used to detect Enterobius vermicularis eggs?

<p>Cellophane tape prep (C)</p> Signup and view all the answers

Microfilariae can be detected in blood specimens.

<p>True (A)</p> Signup and view all the answers

What is the specimen type typically used to collect intestinal protozoa such as Entamoeba histolytica?

<p>Sigmoidoscopy material</p> Signup and view all the answers

The specimen type used to collect fluids from the lungs or liver is called __________.

<p>Aspirates</p> Signup and view all the answers

Match the following specimen types with their possible parasites:

<p>Blood = Plasmodium species Urine = Schistosoma haematobium Sputum = Paragonimus westermani Cellophane tape prep = Enterobius vermicularis</p> Signup and view all the answers

Which of the following is a possible parasite found in bronchoscopic material?

<p>Pneumocystis carinii (A)</p> Signup and view all the answers

Trichomonas vaginalis can only be detected in urine samples.

<p>False (B)</p> Signup and view all the answers

What hypersensitivity reaction is indicated by an immediate wheal and flare response?

<p>Immediate hypersensitivity reaction</p> Signup and view all the answers

Flashcards

Flagellates

Protozoans with whip-like extensions of the cell membrane used for locomotion.

Sporozoa

A type of protozoa that produces spore-like oocysts and alternates between host generations.

Ciliates

Protozoa with hair-like extensions called cilia that function in locomotion.

Protozoan Reproductive Potential

The rapid reproduction of protozoa, resulting in large numbers of offspring.

Signup and view all the flashcards

Trophozoites

The feeding stage of protozoa, found within or outside host cells.

Signup and view all the flashcards

Helminths

A general term encompassing worms.

Signup and view all the flashcards

Trematodes (Flukes)

Flatworms with leaf-like bodies, incomplete digestive systems, and no body cavity. They are hermaphrodites.

Signup and view all the flashcards

Nematodes (Roundworms)

Roundworms with elongated cylindrical bodies, separate sexes, and a fluid-filled internal cavity.

Signup and view all the flashcards

Skin Penetration

Parasites enter the body through the skin, usually by walking on contaminated soil or through the bite of an infected arthropod.

Signup and view all the flashcards

Mouth as a Portal

The most common way for parasites to enter the body, often through contaminated food or hands.

Signup and view all the flashcards

Faecal-Oral Route

The transmission of parasites through contaminated contact is called the faecal-oral route.

Signup and view all the flashcards

Sexual Contact Transmission

Parasites can be transmitted through sexual contact, such as Trichomonas vaginalis.

Signup and view all the flashcards

Congenital Transmission

Some parasites, like Toxoplasma gondii and Plasmodium, can be passed from mother to fetus during pregnancy.

Signup and view all the flashcards

Iatrogenic Infection

Parasites can be transmitted through contaminated blood transfusions or shared needles.

Signup and view all the flashcards

Traumatic Damage

Parasites can enter the body through physical damage to the skin, such as wounds or bites.

Signup and view all the flashcards

Damage During Migration

Parasites can cause damage by migrating through tissues and organs, like hookworm larvae moving through the lungs.

Signup and view all the flashcards

Blood sample collection

Collecting blood samples from a fingertip, earlobe, or vein puncture to examine for parasites like Plasmodium, Babesia, Trypanosoma, and microfilariae.

Signup and view all the flashcards

Skin Snip Collection

Collecting a small piece of skin to examine for Onchocerca volvulus, a parasitic worm that causes river blindness.

Signup and view all the flashcards

Nasal Discharge Collection

Collecting a sample of nasal discharge to examine for Naegleria fowleri, a brain-eating amoeba.

Signup and view all the flashcards

Urine Sediment Collection

Collecting urine sediment to examine for Trichomonas vaginalis, a sexually transmitted parasite.

Signup and view all the flashcards

Cerebrospinal Fluid (CSF) Collection

Collecting cerebrospinal fluid (CSF) through a spinal tap to examine for parasites like Naegleria, Toxoplasma, and trypanosome, which can cause meningitis.

Signup and view all the flashcards

Fecal (Stool) Exam

A diagnostic test used to identify parasites that cause gastrointestinal issues like diarrhea, abdominal cramps, and gas.

Signup and view all the flashcards

Pre-Therapy Stool Specimen Series

A series of 3 stool samples collected on alternate days, within a 10-day timeframe, to detect intestinal parasites.

Signup and view all the flashcards

Post-Therapy Stool Specimen Series

A series of 3 stool samples collected after treatment to confirm the effectiveness of therapy for parasitic infections.

Signup and view all the flashcards

Cellophane Tape Prep

A method for collecting Enterobius vermicularis (pinworm) eggs by using clear tape to collect eggs from the anal area.

Signup and view all the flashcards

Amebiasis

A parasitic infection caused by the Entamoeba histolytica parasite, which can lead to intestinal inflammation and ulcers.

Signup and view all the flashcards

Cryptosporidiosis

A parasitic infection caused by the Cryptosporidium parvum parasite, which can cause watery diarrhea and stomach cramps.

Signup and view all the flashcards

Giardiasis

A parasitic infection caused by the Giardia lamblia parasite, which can cause diarrhea, gas, and abdominal cramps.

Signup and view all the flashcards

Paragonimiasis

A parasitic infection caused by the Paragonimus westermani fluke, which can cause coughing, chest pain, and difficulty breathing.

Signup and view all the flashcards

Enterobius vermicularis egg

The microscopic egg of the parasitic roundworm Enterobius vermicularis, commonly known as pinworm.

Signup and view all the flashcards

Entamoeba histolytica

A single-celled parasitic protozoan that can cause amoebiasis, an intestinal infection.

Signup and view all the flashcards

Giardia lambia

A parasitic protozoan that infects the small intestine and can cause diarrhea, cramping, and dehydration.

Signup and view all the flashcards

Pneumocystis carinii

A parasitic protozoan that infects the lungs and can cause pneumonia, especially in people with weakened immune systems.

Signup and view all the flashcards

Schistosoma haematobium

A blood fluke that infects the urinary bladder and can cause blood in the urine, pain, and discomfort.

Signup and view all the flashcards

Trichomonas vaginalis

A parasitic protozoan that infects the vagina and can cause vaginal discharge, itching, and discomfort.

Signup and view all the flashcards

Entamoeba gingivalis

A single-celled parasite that can cause amoebic gingivitis, a gum infection.

Signup and view all the flashcards

Acanthamoeba species

A parasitic protozoan that can infect the cornea and cause keratitis, an inflammation of the cornea.

Signup and view all the flashcards

Parasitology

The scientific study of organisms that live in or on other organisms, often causing harm.

Signup and view all the flashcards

Parasite

An organism that lives in or on another organism, benefiting from the host while causing harm.

Signup and view all the flashcards

Parasitism

A symbiotic relationship where one organism benefits (the parasite) while the other is harmed (the host).

Signup and view all the flashcards

Symbiosis

A relationship where both organisms benefit from each other.

Signup and view all the flashcards

Obligate Parasite

A parasite that is completely dependent on a host for survival. It cannot live independently.

Signup and view all the flashcards

Facultative Parasite

An organism that can live as a parasite but doesn't have to. It can survive independently.

Signup and view all the flashcards

Ectoparasite

A parasite that lives on the surface of the host.

Signup and view all the flashcards

Endoparasite

A parasite that lives inside the body of the host.

Signup and view all the flashcards

Commensal

An organism that lives in a relationship where it benefits without harming or helping the other organism.

Signup and view all the flashcards

Host

The organism harboring the parasite, providing nourishment and shelter.

Signup and view all the flashcards

Definitive Host

The host harboring the sexually mature adult stage of the parasite.

Signup and view all the flashcards

Intermediate Host

The host harboring the immature larval or asexual stage of the parasite.

Signup and view all the flashcards

Paratenic Host

A host that acts as a transport agent for the parasite. The parasite does not undergo development in this host.

Signup and view all the flashcards

Compromised Host

A host with weakened defense mechanisms, making it more susceptible to infection.

Signup and view all the flashcards

Pathogen

A parasite that is capable of causing disease.

Signup and view all the flashcards

Infestation

The presence of arthropods (insects, ticks, mites) on the skin of the host.

Signup and view all the flashcards

Study Notes

Introduction to Parasitology

  • Medical parasitology is the study of parasites that infect humans, causing disease and misery, especially in tropical regions.
  • These parasites affect billions globally, causing millions of deaths annually and causing debilitating illnesses like blindness and disfigurement in many more.
  • The World Health Organization estimates that one in four people harbor parasitic worms.

Learning Outcomes

  • Students will be able to define general terms used in parasitology.
  • Students will be able to identify the parasitic form causing disease in humans and its location in the body.
  • Students will be able to describe how parasitic infections occur.
  • Students will be able to identify the sources of parasitic infections.
  • Students will be able to discuss diagnostic tests for parasitic diseases.

Definitions of Terms

  • Parasitology: The study of parasites.
  • Parasites: Organisms that live on or in another living organism (the host) to obtain food and shelter, often causing disease to the host.
  • Parasitism: A symbiotic relationship where one organism (the parasite) benefits, and the other (the host) is harmed.
  • Symbiosis: A close relationship between two species where at least one benefits. Parasites and hosts are typically not equal in their symbiotic benefits.
  • Obligate parasite: A parasite that is completely dependent on a host for survival.
  • Facultative parasite: A parasite that can switch between a parasitic lifestyle and a free-living lifestyle.
  • Ectoparasite: A parasite that lives on the surface of the host (e.g., mites, ticks, lice).
  • Endoparasite: A parasite that lives inside the host's body (e.g., parasitic protozoa and helminths).
  • Commensalism: A symbiotic relationship in which one organism benefits, and the other is neither harmed nor helped.
  • Host: An organism that harbors a parasite and provides nourishment and shelter.
  • Definitive host: The host in which the parasite reaches sexual maturity.
  • Intermediate host: The host that harbors the parasite’s larval or asexual stages.
  • Paratenic host: A host that helps transport a parasite to a definitive host without the parasite developing within it.
  • Compromised host: A host whose normal defense mechanisms are impaired (e.g., through AIDS).
  • Pathogen: A parasite that causes disease.
  • Pathogenicity: The ability of a parasite to cause disease.
  • Zoonosis: A disease that can be transmitted between humans and animals.
  • Virulence: The degree of pathogenicity of a parasite.
  • Vector: An organism that transmits a parasite from one host to another (often an insect).
  • Infestation: Presence of arthropods on the host's skin.
  • Microparasite: A small, unicellular parasite that multiplies within its host.
  • Macroparasite: A large, multicellular parasite that usually doesn’t reproduce directly in its vertebrate host.

Parasites

  • Protozoa: Unicellular organisms.
  • Helminths: Multicellular organisms (worms)

Protozoa

  • Classifications based on locomotion type: Rhizopoda (e.g., Amoeba), Flagellates (e.g., Leishmania), Sporozoa (e.g., Plasmodium), Ciliates (e.g., Balantidium)
  • Specific protozoa and their classification by group/species are listed (e.g., Amoeba: Entamoeba histolytica, Flagellates: Giardia lamblia, etc...).

Helminths

  • Multicellular organisms.
  • Classified as Cestodes (tapeworms), Trematodes (flukes), and Nematodes (roundworms).
  • Specific helminths and their classification by group/species are listed (e.g., Cestodes: Taenia saginata, Trematodes: Schistosoma, etc...).

Parasites (Micro/Macro)

  • Microparasites are small, unicellular and multiply in their hosts, often inside host cells (e.g. protozoa).
  • Macroparasites are large multicellular and usually have no direct reproduction (e.g. helminths) within their host.

Protozoa- Life Cycles

  • Not all protozoa are parasitic. Some protozoa are free-living in water, and become parasitic when accidentally introduced to the body.
  • They multiply rapidly leading to potentially serious infections.
  • Transmission can occur through fecal-oral routes or vectors such as mosquitoes and sandflies.

Types of Protozoa

Specific examples of amoebae, flagellates, sporozoa, and ciliates and their functions or characteristics are mentioned.

Helminth Life Cycles

  • Helminths have complex life cycles.
  • Stages include eggs, larvae, and adult stages.
  • Definitive hosts are often mammals, and intermediate hosts can vary.
  • Larval stages may be free-living or parasitize invertebrate vectors.

Mode/Sources of Transmission

  • Specific examples (contaminated water/soil, raw/undercooked meat, blood-sucking insects, etc.) are provided.

Modes of Infection

  • Infection routes include autoinfection, waterborne, vector-borne, animal-borne, contaminated food, and penetration through the skin.

Portal of Entry

  • Parasite entry into the body may occur via the mouth (contaminated food/water), skin (walking on contaminated soil), sexual contact, Congenital route, inhalation or through Iatrogenic methods.

Harmful Effects of Parasites

  • Traumatic damage
  • Lytic necrosis
  • Competition for nutrients
  • Inflammatory reaction
  • Allergic manifestations
  • Neoplasia

Immunity to Parasitic Infections

  • Initial immune response is IgM followed by IgG.
  • IgE response high during helminth or ectoparasite infections
  • Immunity is often concomitant - lasting only as long as the original infection remains present.
  • Protective immune response includes cytotoxic T cells, natural killer cells, activated macrophages, and antibodies.

Parasites in Immunocompromised Hosts

  • Immunocompromised individuals (e.g., those with AIDS, transplant patients, cancer patients, or steroid users) are more susceptible to parasitic infections. Specific parasites associated with these conditions are mentioned (toxoplasma gondii, pneumocystis carinii, cryptosporidium parvum).

Preventive Measures

  • Washing hands with soap and water (before/after eating/using the toilet/handling animals)
  • Avoidance of eating raw/undercooked meat
  • Avoiding cross-contamination during food preparation
  • Disinfecting cutting boards, utensils
  • Sanitation of water sources
  • Safe sex practices
  • Use of preventative medications like chloroquine where endemic

Laboratory Examinations

  • Diagnostic testing is crucial.
  • Purpose of diagnostic testing (establishing diagnoses, assessing severity, monitoring progress, monitoring treatment effectiveness)
  • Specific specimen preparation methods, including handling and transport details, are provided (e.g. fecal, urine, sputum, tissue biopsy, skin snips, mucosal scrapings)
  • Specific laboratory tests discussed such as, but not limited to, a fecal specimen (including pre and post-therapy requirements), cell preparation methods (e.g. cellulose tape prep), sigmoidoscopy, sputum exam, scraping, skin testing, and more.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

Related Documents

Introduction To Parasitology PDF

Description

Explore the fascinating world of medical parasitology, focusing on the parasites that infect humans and the diseases they cause. This quiz covers essential terminology, diagnostic tests, and the impact of parasitic infections on global health. Enhance your understanding of how these organisms operate and the implications for public health.

More Like This

Parasitic Worms Quiz
10 questions

Parasitic Worms Quiz

ThumbUpPearl avatar
ThumbUpPearl
Medical Parasitology Basics
6 questions

Medical Parasitology Basics

SensibleChrysanthemum avatar
SensibleChrysanthemum
Dracunculiasis (Guinea-worm Disease)
24 questions

Dracunculiasis (Guinea-worm Disease)

FeatureRichDeciduousForest avatar
FeatureRichDeciduousForest
Ascaris Lumbricoides: Characteristics and Classification
10 questions

Ascaris Lumbricoides: Characteristics and Classification

SelfSufficientKangaroo avatar
SelfSufficientKangaroo
Use Quizgecko on...
Browser
Open
Browser
Browser