Exam 3: Antiprotozoal/Antihelmintic Flashcards
What is the DOC for an invasive amebiasis infection caused by Entamoeba histolytica?
Metronidazole + Luminal amebicide
What protozal form is infective and inactive?
Cyst
What protozal form is active and can invade tissues?
Trophozoite
What causes a patient to have symptoms from an Entamoeba histolytica infection?
If the cyst forms into trophozoites that invade the tissue of the intestinal wall
What is the DOC for an asymptomatic amebiasis infection caused by Entamoeba histolytica?
Luminal amebicide (Iodoquinol or Paraomomycin)
What is the DOC for a giardiasis infection caused by Giardia lamblia?
Metronidazole
What is the most common cause of non-bacterial diarrhea in North America?
Giardia lamblia
What is the DOC for a trichomoniasis infection caused by Trichomoniasis vaginalis?
Metronidazole
How are amebiasis and giardiasis infections transmitted?
Contact with contaminated feces, food, or water
How is a trichomoniasis infection transmitted?
Sexually transmitted
Men often asymptomatic, tx both partners
What is the DOC for a toxoplasmosis infection caused by Toxoplasma gondii?
Pyrimethamine + Sulfadiazine + Folinic acid
What pathogen is common in cats and can cause serious fetal infection?
Toxoplasma gondii
What is the DOC for a pneumocytosis infection caused by Pneumocystis jirovecii?
Trimethoprim + Sulfamethoxazole + Folinic acid
Is Pneumocystis jirovecii a protozoa?
No, it is a yeast-like fungus
What infection is a major cause of death in AIDs patients?
Pneumocytosis
What can be given as a prophylaxis treatment as apart of HIV therapy to prevent pneumocytosis infections?
Trimethoprim + Sulfamethoxazole + Folinic acid
What are the tissue amecicide drugs?
Metronidazole
Tinidazole
Emetine and Dehydroemetine
What are the luminal amecicide drugs?
Iodoquinol
Paramomycin
Diloxanide furoate
Tetracycline and Erythromycin
What is the MOA of metronidazole?
Reacts with ferrodoxin (found only in anaerobes)
Metronidazole metabolites are taken up into DNA and form unstable molecules
What is metronidazole DOC for?
Invasive entamoeba histolytica (with a luminal amebocide)
Giardia lamblia
Trichomonas vaginalis
What are the toxicities associated with metronidazole?
Dysgeusia (metalic taste)
Disulfiram-like reactiin
What can Tinidazole be used to treat?
Alternative to metronidazole for tx of:
Invasive entamoeba histolytica (with a luminal amebocide)
Giardia lamblia
Trichomonas vaginalis
What can Emetine and Dehydroemetine be used to treat?
Alternative to metronidazole for tx of severe intestinal or systemic entamoeba histolytica infections
What are the toxicities associated with Emetine and Dehydroemetine?
Cardiotoxicity
GI effects
Teratogenic
What are contraindication of Emetine and Dehydroemetine?
Cardiac disease
Renal disease
Pregnancy
What is Iodoquinol DOC for?
Asymptomatic entamoeba histolytica
Invasive entamoeba histolytica (with a tissue amebocide)
What is Paraomomycin DOC for?
Asymptomatic entamoeba histolytica
Invasive entamoeba histolytica (with a tissue amebocide)
Can also be used to treat giardia lamblia and trichomonas vaginalis
What are the toxicities associated with Iodoquinol?
High iodine content (enlarged thyroid)
Optic neuritis and optic atrophy that can lead to blindness
What can Diloxanide furoate be used to treat?
Alternative to Iodoquinol or Paromoycin for treatment of invasive entamoeba histolytica (with a tissue amebocide)
What can Tetracycline and Erythromycin be used to treat?
Alternative for treatment of amebiasis and giardiasis
What can is an alternative drug an HIV patient can take instead of Trimethoprim + Sulfamethoxazole for treatment of P. pneumonia?
Why would you not use this drug as a first choice?
Pentamidine
Not as effective, more expensive, more toxicities
What are the DOC for treatment of a roundworm (nematode) infection?
Albendazole or mebendazole Pyrantel pamoate (OTC)
What drug is an alternative for treatment of a roundworm (nematode) infection?
Ivermectin
What is the DOC for a fluke (trematode) infection?
Praziquantel
What is the DOC for a tapeworm (cestode) infection?
Praziquantel
What drug is an alternative for treatment of tapeworm (cestode) infection?
Albendazole
What is the MOA of Albendazole or Mebendazole?
Inhibits microtubules polymerization by binding to b-tubulin, preventing glucose uptake
What is the MOA of Pyrantel pamoate?
Cholinesterase inhibitor; produces depolarizing neuromuscular bloackade
What is the MOA of Ivermectin?
Paralyzes the parasite; intensifies GABA mediated transmission of signals in peripheral nerves
