Malaria Pathology and Treatment Quiz
45 Questions
6 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 species of Plasmodium can remain in a latent exoerythrocytic form for extended periods?

  • P.vivax (correct)
  • P.ovale (correct)
  • P.falciparum
  • P.malariae

What is the sequence of development for merozoites once they invade erythrocytes?

  • Ring forms -> trophozoites -> erythrocytic schizonts (correct)
  • Erythrocytic schizonts -> trophozoites -> ring forms
  • Trophozoites -> ring forms -> erythrocytic schizonts
  • Gametocytes -> trophozoites -> merozoites

How long do P.falciparum and P.malariae remain in the primary exoerythrocytic stage in the liver?

  • 4 weeks (correct)
  • 2 weeks
  • 6 weeks
  • 1 week

What can merozoites develop into after invading erythrocytes?

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

During which stage do merozoites undergo sexual reproduction?

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

What is a characteristic feature of falciparum malaria?

<p>High level of parasitemia (D)</p> Signup and view all the answers

Which type of drug targets the developing or dormant liver forms of malaria?

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

What are drugs that act on erythrocytic parasites called?

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

Which stage of malaria drugs prevent transmission to mosquitoes?

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

What serious complication is commonly associated with P. falciparum infections?

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

Which term best describes the extensive destruction of red blood cells in malaria?

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

What is true about radical cure agents for malaria?

<p>No single agent is considered a radical cure (A)</p> Signup and view all the answers

What mode of malaria transmission is referenced involving direct contact?

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

What is the drug of choice for the treatment of asymptomatic intestinal infection caused by E. histolytica?

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

Which of the following conditions is NOT treated with Metronidazole?

<p>Asymptomatic intestinal infection (A)</p> Signup and view all the answers

What common adverse effect is associated with Metronidazole?

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

Tinidazole is known to be effective for which of the following infections?

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

Which of the following treatments is NOT effective against luminal parasites?

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

What is the recommended single dose for treating Trichomoniasis with Metronidazole?

<p>2 g (B)</p> Signup and view all the answers

What is a rare but serious adverse effect of Metronidazole?

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

Which of the following side effects is most likely due to Metronidazole?

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

What is the mechanism of action for primaquine?

<p>Its mechanisms of antimalarial action are unknown. (D)</p> Signup and view all the answers

What is the primary excretion route for mefloquine?

<p>Bile and feces (D)</p> Signup and view all the answers

Which condition is a contraindication for using mefloquine?

<p>History of convulsions (D)</p> Signup and view all the answers

What is the approximate half-life (T1/2) of primaquine?

<p>3-8 hours (A)</p> Signup and view all the answers

Which of the following statements about mefloquine absorption is correct?

<p>It is well absorbed and absorption is increased by food. (A)</p> Signup and view all the answers

What is the recommended administration strategy to minimize mefloquine toxicity?

<p>Administer in two divided doses 6-8 hours apart. (D)</p> Signup and view all the answers

Which statement is true about primaquine's role in treating malaria?

<p>It is the drug of choice for addressing liver forms of P. vivax and P. ovale. (C)</p> Signup and view all the answers

What is the correct volume of distribution (Vd) for mefloquine?

<p>20 L/kg (D)</p> Signup and view all the answers

What is the primary mechanism of action of albendazole?

<p>Inhibiting microtubule synthesis (D)</p> Signup and view all the answers

Which of the following infections is albendazole NOT effective against?

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

What effect does a high-fat meal have on the absorption of albendazole?

<p>Increases absorption up to 5 times (B)</p> Signup and view all the answers

What is the half-life (T1/2) of albendazole?

<p>8-12 hours (B)</p> Signup and view all the answers

Which of the following drugs would likely decrease the effectiveness of albendazole?

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

What is the distribution of albendazole following administration?

<p>In urine, bile, liver, and cyst fluid (B)</p> Signup and view all the answers

Albendazole excretion primarily occurs through which route?

<p>Renal as albendazole sulfoxide (A)</p> Signup and view all the answers

What is the main clinical use of praziquantel?

<p>Effective against schistosomiasis (A)</p> Signup and view all the answers

What is a common adverse reaction to praziquantel?

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

What effect does food have on the absorption of praziquantel?

<p>Increases absorption with high-carbohydrate meals (C)</p> Signup and view all the answers

Which of the following populations is safety established for praziquantel?

<p>Children older than 2 years (C)</p> Signup and view all the answers

What is a major contraindication for the use of praziquantel?

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

What is the typical bioavailability of praziquantel?

<p>80% (A)</p> Signup and view all the answers

What is the maximum plasma concentration time (Tmax) for praziquantel?

<p>1-2 hr (C)</p> Signup and view all the answers

Which of the following conditions is praziquantel mainly used to treat?

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

Which of the following is a possible mild adverse reaction to praziquantel?

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

Flashcards

Primary Exoerythrocytic Stage

The stage of the malaria parasite's lifecycle where it resides in the liver cells before infecting red blood cells.

Latent Exoerythrocytic Stage

The ability of certain malaria parasites (P.vivax and P.ovale) to remain dormant in the liver for long periods, causing relapses of the disease.

Intraerythrocytic Stage

Following the primary exoerythrocytic stage, the merozoites (the infective form of the parasite) invade red blood cells and develop into different stages.

Erythrocytic Schizonts

The parasitic forms that develop in the red blood cells, going through different stages (ring forms, trophozoites, and schizonts), eventually multiplying and releasing more merozoites.

Signup and view all the flashcards

Sexual Stage

The stage of the malaria parasite lifecycle where it transitions from asexual reproduction in the human host to sexual reproduction within the mosquito vector.

Signup and view all the flashcards

Parasitemia

The ability of a parasite to invade red blood cells

Signup and view all the flashcards

Plasmodium falciparum

A type of malaria parasite that can cause severe complications.

Signup and view all the flashcards

Erythrocytic phase

The stage of malaria infection where the parasite lives in red blood cells.

Signup and view all the flashcards

Tissue schizonticides

Drugs that kill the dormant liver stages of malaria parasites

Signup and view all the flashcards

Blood schizonticides

Drugs that kill the malaria parasite in red blood cells.

Signup and view all the flashcards

Gametocides

Drugs that kill the sexual stages of malaria parasites, preventing transmission to mosquitoes.

Signup and view all the flashcards

Hemolysis

The destruction of red blood cells, often caused by malaria.

Signup and view all the flashcards

Splenomegaly

Enlargement of the spleen, often caused by malaria.

Signup and view all the flashcards

Mefloquine Absorption

Mefloquine is well absorbed, reaching peak concentration in the body after 18 hours. Food enhances its absorption.

Signup and view all the flashcards

Mefloquine Protein Binding

Mefloquine binds to proteins in the bloodstream to a significant extent, with around 98% being bound.

Signup and view all the flashcards

Mefloquine Half-Life

Mefloquine's elimination half-life is long, about 3 weeks, making it suitable for weekly dosing for malaria prevention.

Signup and view all the flashcards

Mefloquine Metabolism

Mefloquine is broken down by the CYP3A4 enzyme in the liver. This plays a role in how the drug is processed and eliminated.

Signup and view all the flashcards

Mefloquine Excretion

Mefloquine can be excreted through bile and feces, with only a small amount leaving the body through urine.

Signup and view all the flashcards

Primaquine Absorption

Primaquine is effectively absorbed into the body.

Signup and view all the flashcards

Primaquine Metabolism

The CYP1A2 enzyme is responsible for converting Primaquine into an active metabolite called carboxyprimaquine, which contributes to its antimalarial activity.

Signup and view all the flashcards

Primaquine Excretion

Primaquine is eliminated from the body primarily through urine, with a small amount of the unchanged drug being excreted.

Signup and view all the flashcards

Entamoeba histolytica Infections

Entamoeba histolytica is a parasite that can cause various intestinal and extraintestinal infections, ranging from asymptomatic infections to severe dysentery, ameboma, and liver abscesses.

Signup and view all the flashcards

Asymptomatic Intestinal Infection

This refers to the parasite residing within the intestinal lumen without causing any symptoms.

Signup and view all the flashcards

Amebic Colitis

Characterized by inflammation and ulcers in the colon, often accompanied by diarrhea, abdominal pain, and blood in the stool.

Signup and view all the flashcards

Extra-intestinal Infections

Entamoeba histolytica can spread beyond the intestines, causing infections in other organs such as the liver, lungs, or brain.

Signup and view all the flashcards

Treatment for Tissue Infections

Metronidazole and tinidazole are commonly used to treat tissue infections caused by Entamoeba histolytica.

Signup and view all the flashcards

Luminal Amebicides

These drugs are used to eliminate the parasite from the intestinal lumen, where it can survive and cause reinfection.

Signup and view all the flashcards

Giardiasis

Giardiasis is a parasitic infection of the small intestine caused by Giardia lamblia, leading to diarrhea, abdominal cramps, and bloating.

Signup and view all the flashcards

Treatment for Trichomoniasis

Metronidazole is the drug of choice for treating trichomoniasis, a sexually transmitted infection caused by the parasite Trichomonas vaginalis.

Signup and view all the flashcards

Albendazole

A broad-spectrum antihelminthic drug that inhibits microtubule synthesis, leading to energy depletion, immobilization, and death of the worm.

Signup and view all the flashcards

Benzimidazole Antihelminthic

A type of antihelminthic drug that acts by interfering with microtubule synthesis, which is essential for the growth and development of parasitic worms.

Signup and view all the flashcards

Hyperparasitism

A condition where the blood contains a high number of parasitic worms.

Signup and view all the flashcards

Hypersensitivity

A condition where the host's immune system overreacts to a parasitic infection, leading to excessive inflammation and tissue damage.

Signup and view all the flashcards

Metabolism

The process by which a drug is broken down in the body, often resulting in the formation of a more active form of the drug.

Signup and view all the flashcards

Leukopenia

A significant reduction in the number of white blood cells in the blood, which can make the body more susceptible to infections.

Signup and view all the flashcards

Leukocytosis

An increase in the number of white blood cells in the blood, often due to infection or inflammation.

Signup and view all the flashcards

Excretion

The elimination of a drug or its byproducts from the body through various pathways such as urine, feces, or sweat.

Signup and view all the flashcards

What is Niclosamide?

Niclosamide is a medication used to treat tapeworm infections. It works by preventing the tapeworm from absorbing nutrients, causing it to die and be eliminated from the body.

Signup and view all the flashcards

What are the common side effects of Niclosamide?

Niclosamide is typically well tolerated with infrequent, mild side effects that usually go away on their own.

Signup and view all the flashcards

Can I drink alcohol while taking Niclosamide?

Alcohol should not be consumed during or for one day after taking Niclosamide.

Signup and view all the flashcards

What is Praziquantel?

Praziquantel is a medication used to treat various parasitic worm infections, particularly schistosomiasis. It works by paralyzing and detaching the worms from the body's tissues.

Signup and view all the flashcards

How does Praziquantel work in the body?

Praziquantel is rapidly absorbed into the bloodstream and reaches its peak levels within 1-2 hours after taking it. It reaches the cerebrospinal fluid, binds to proteins in the body, and is eliminated through urine and feces.

Signup and view all the flashcards

What are the common side effects of Praziquantel?

Praziquantel is generally well tolerated. Common side effects include headache, dizziness, drowsiness, and tiredness. These effects tend to be mild and often disappear as the treatment continues.

Signup and view all the flashcards

Who should avoid Praziquantel?

Praziquantel is generally safe for children but should be used with caution in pregnant women. It is contraindicated in patients with ocular cysticercosis due to the risk of eye damage.

Signup and view all the flashcards

How much Praziquantel should I take?

The dosage of Praziquantel might need to be adjusted based on the patient's weight and the type of parasitic infection being treated. It should always be taken as prescribed by a doctor.

Signup and view all the flashcards

Study Notes

Pharmacology of Antiparasitic Agents and Parasite Diseases

  • The presentation covers the pharmacology of antiparasitic agents and parasite diseases.
  • It includes a discussion of antiprotozoal drugs, antimalarial drugs, drugs for treating amebiasis, and anthelmintic drugs.

Introduction of Malaria

  • Malaria is caused by the Plasmodium protozoan.
  • The Anopheles mosquito transmits the disease.
  • It infects approximately 300-500 million people annually.
  • About 2000 people die each day.
  • Malaria prevalence has risen in many tropical regions.
  • It is a threat to non-endemic countries and travelers.

Epidemiology

  • The geographic distribution of Plasmodium species is not fully documented.
  • Plasmodium vivax is more prevalent in India, Pakistan, Bangladesh, Sri Lanka, and Central America.
  • Plasmodium falciparum is prevalent in Africa, Haiti, Dominican Republic, the Amazon region of South America, and New Guinea.
  • Plasmodium ovale is found in Africa.
  • Plasmodium malariae is found worldwide.
  • In the United States, most malaria cases are in immigrants from endemic areas and travelers.
  • Thailand has P. vivax at 56.8% and P. falciparum at 42.5%.

Life Cycle

  • The life cycle involves a mosquito vector.
  • Mosquito injects sporozoites into human host.
  • Asexual multiplication occurs in the liver.
  • Merozoites invade red blood cells and replicate.
  • Gametocytes are formed and enter the mosquito.

Primary Attack & Relapse

  • A bite from an infected mosquito initiates the primary attack.
  • Infection with P. vivax and P. ovale can cause relapses.

Antibodies & Immunity

  • Antibodies to sporozoites block liver invasion.
  • CD4+ and CD8+ T cells kill intrahepatic parasites.
  • Antibodies block merozoite invasion of red blood cells.
  • Antibody-dependent cytotoxicity kills intraerythrocytic parasites.
  • Antibodies block parasite development and invasion.

Stages of Malaria in Liver & Blood

  • P. falciparum and P. malariae remain in primary exoerythrocytic stage in the liver for up to 4 weeks.
  • P. vivax and P. ovale can exist in the liver during latent stages, therefore, infected people may experience relapse.
  • Merozoites invade erythrocytes and transform into ring forms, trophozoites, and erythrocytic schizonts.
  • P. falciparum* has high parasitemia, causing more severe infections.

Drugs for Malaria Treatment

  • Drugs that eliminate developing or dormant liver forms are called tissue schizonticides.
  • Drugs that target erythrocytic parasites are blood schizonticides.
  • Drugs that kill sexual stages and prevent transmission to mosquitoes are gametocides.
  • No single agent provides a complete cure.

Pathology

  • Malaria's erythrocytic phase causes hemolysis and splenomegaly.
  • Most serious complications are associated with P. falciparum.
  • Infants and children under 5, as well as pregnant women without immunity, are at high risk for severe complications.
  • High parasitemia and sequestration in capillaries and postcapillary vessels of organs like the brain and kidney lead to organ damage and potentially fatal outcomes.

Characteristics of Malaria Parasites

  • The presentation provides a table comparing the characteristics of P. falciparum, P. vivax, P. ovale, and P. malariae.

Clinical Presentation of Malaria

  • The clinical presentation may include nonspecific symptoms like fever, chills, and sweating.
  • More severe symptoms such as severe anemia, high parasitemia, and neurological complications might occur.

Classification of Antimalarial Drugs

  • The table categorizes antimalarial drugs by their action on different stages of the parasite.

Treatment of Malaria

  • Treatments vary based on Plasmodium species, patient factors, and resistance patterns.

Chloroquine

  • Used for susceptible P. falciparum and P. malariae infections.
  • Inhibits Plasmodium polymerization of heme.
  • Resistance is common.

Piperaquine

  • A treatment option for chloroquine-resistant cases.
  • Effective as part of a combination therapy.
  • Exhibits resistance, hence combination therapies are now common, particularly in malaria-endemic areas and with multidrug resistance.

Artemisinin & Derivatives

  • Artemisinin is a sesquiterpene derivative with rapid antimalarial activity.
  • Effective against blood schizonts, but not mature gametocytes.
  • Effective in the treatment of severe malaria.
  • Analogues like artesunate, artemether, and dihydroartemisinin are used to effectively improve solubility, and improve administration options for malaria treatment.

Atovaquone

  • Used as part of combination therapy to prevent the development of resistance.

Amebiasis (Entamoeba histolytica)

  • It can cause asymptomatic intestinal infection, colitis, severe intestinal infection (dysentery), ameboma, and liver abscess.

Metronidazole

  • A treatment of choice for amebiasis.
  • Effective against luminal parasites, but has limited effect on hepatic stages.

Anthelminthic Drugs

  • Albendazole, Mebendazole, Diethylcarbamazine citrate (DEC), Ivermectin, Niclosamide, Praziquantel, and Pyrantel pamoate are used to treat helminthic infections.
  • Helminths (worms) cause a range of diseases, infecting billions of people, including intestinal nematodes, as well as flukes and tapeworms

Drugs for Helminthic Infections

  • This section provides tables listing the drugs of choice and alternative medications for various types of helminth infections (by organ system).

Mefloquine

  • Strong blood schizonticidal activity against P. falciparum and P. vivax.
  • Not active against hepatic stages.
  • Can be used in areas with chloroquine-resistant strains.

Primaquine

  • Drug of choice for liver forms of P. vivax and P. ovale.
  • Can eradicate liver hypnozoites and prevent relapses.
  • Includes relevant publications about antiprotozoal and antihelminthic drugs available in scientific literature.

Studying That Suits You

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

Quiz Team

Related Documents

Antiparasitic Agents PDF

Description

Test your knowledge on malaria, its life cycle, and treatment strategies with this detailed quiz. Explore questions about Plasmodium species, the development of merozoites, and the characteristics of falciparum malaria. Perfect for students studying parasitology or infectious diseases.

More Like This

Malaria and Plasmodium Species Quiz
5 questions

Malaria and Plasmodium Species Quiz

InventiveNickel avatar
InventiveNickel
Malaria and Plasmodium Species
68 questions

Malaria and Plasmodium Species

LovedRhenium avatar
LovedRhenium
Malaria Parasite Infections and Misidentification
0 questions

Malaria Parasite Infections and Misidentification

WellConnectedArithmetic avatar
WellConnectedArithmetic
Malaria Overview and Life Cycle
23 questions

Malaria Overview and Life Cycle

FeistyRuby6245 avatar
FeistyRuby6245
Use Quizgecko on...
Browser
Open
Browser
Browser