Specimen Collection and Parasitic Drugs

Specimen of Interest for Trophozoites (1)(1)

• Raw/fresh fecal specimens

  • 30-60 minutes to the laboratory

Specimen of Interest for Protozoa and Helminths (1)(2)

• Preserved fecal specimens

  • Formalin vial: helminths, protozoa (iodine stain)

    Polyvinyl alcohol vial: protozoa (Trichrome stain)

Specimen of Interest for Malaria

Whole blood (Thin and thick smears)

Other Specimen of Interests (3)

• Skin snips; biopsy; pull something out of eye

• Zinc sulfate flotation technique

• Kato-Katz

Zinc sulfate flotation technique (4)

• Solutions have higher specific gravity than parasites

• Organisms rise to top; debris sinks to bottom

• Cleaner preparation than ether sedimentation

• Walls of eggs/cysts may collapse; some won’t float

Kato-Katz (3)

• Quantitate helminth, schistosome eggs

• Sieve-like procedure with staining

• Not typically used in clinical setting

AL/ME BENDAZOLE (How it works, What organism, How Taken, Affinity)

• Binds to Beta-tubulin (cytoskeletal protein), affecting parasite “intestinal” absorption

• Good for nematodes (adult, developing embryo)

• Oral

• 100X more affinity for parasite Beta-tubulin than

  human Beta-tubulin

IVERMECTIN (How it works, What organism, How Taken, Affinity)

• Causes influx of Ca2+ into nerve and muscle cell membranes; paralysis and death of parasites

• Good for nematodes

• Oral

• 100X more affinity for parasite nerve/muscle membranes than mammalian brain tissue

PRAZIQUANTEL (How it works, What organism, How Taken, Other)

• Causes structural changes to parasite teguments, increased Ca2+ into cytosol; paralysis of parasite

• Good for cestode and trematode adults; no eggs

• Oral

• Parasite antigens also (now) exposed for host immune response

PERMETHRIN (How it works, What organism, How Taken)

• Disrupts neuronal function in mites and lice

• Good for scabies and lice

• Topical

CHLOROQUINE (How it works, What organism, How Taken, Other)

• Causes accumulation of porphyrin precursors that are toxic to the parasite

• Good for Plasmodium spp. (can be resistant)

• Oral

• Inexpensive, safe agent for malaria prophylaxis

Mefloquine (What used for?)

• Type of Chloroquine

• Good for Rx and prophylaxis

Quinine (How taken and what organism)

• Type of Chloroquine

• PO,IV

• Also combined with clindamycin for Babesia spp