Antiparasitic and Antifungal Agents

1. Antiparasitic and Antifungal Agents

2. Antiparasitic Therapy • Millions of people worldwide are infected with protozoal organisms. • Protozoa: a single-celled microorganism

3. Protozoal Infections • Protozoa: single-celled organisms • Most are free-living and produce their own food • Some require a host for food • Infections range from asymptomatic to life-threatening • More prevalent with the advance in worldwide AIDS cases

4. Protozoal Illnesses • prevalent in tropical regions and in immuno-compromised hosts • Exposure: international travel and immigration

5. Malaria • high morbidity and mortality • Protozoa called Plasmodium • Resides in and destroys the red blood cell of humans • S/S: • Fever, prostration, and recurrent chills • Malaria is transmitted by the bite of a female mosquito

6. Transmission of Malaria • Transmission: certain species of the Anopheles genus • Malaria is also transmitted via infected blood during transfusions • less than 1: 1million units (CDC, 2010)

7. Treating Malaria • Humans: antimalarial agents work during the asexual cycle of the parasite • Mosquito: antimalarial agents do not work during the sexual cycle

8. Diagnosis of Malaria • Diagnosis by symptoms and indentifying parasite within the red blood cells • Blood smear must be done during symptomatic stage

9. Antimalarial Agents • Quinine Sulfate: action is still not well understood • Declining in use because of toxic effects: cinchonism, hemolytic anemia, thrombocytopenia, agranulocytosis • Melfloquine (Lariam): synthetic analogue of quinine sulfate • Used as preventative therapy and has fewer side effects

10. Antimalarial Agents • Chloroquine (Aralen): safer and effective • -Used for acute treatment, prevention • -Fewer side effects • -Given orally and IM

11. Treatment with Antimalarials • Clients • Take antimalarial agents 1 to 2 weeks before travel to designated geographic areas • Monitor for toxicity • Headache, drowsiness, visual disturbance, seizure • Lab follow-up: monitor for low WBC • Note reduction in neutrophils • Administer with food; causes GI irritation

12. Other Protozoal Infections • Amebiasis: Entamoeba histolytica • Contaminated food and drink • Signs and symptoms: diarrhea • Treatment: metronidazole (Flagyl) • Trichomoniasis • Sexually transmitted disease of the vagina • Treatment: metronidazole (Flagyl)

13. Antiprotozoal Agents • Metronidazole (Flagyl): bacteriocidal, amebicidal, and trichomonacidal; it also kills some anerobic bacteria • Adverse effects: N&V, convulsions, peripheral neuropathy, blurred vision, metallic taste, diarrhea, darkened urine, bone marrow depression, and rash • If taken with alcohol, produces a disulfiram reaction: abdominal cramps, nausea, headache

14. Intestinal Parasitic Disorder • Helminthiasis-infection with parasitic worms • Most common protozoan infection • Eradicated by the use of safe anthelmintic drugs: mebendazole (Vermox), pyrantel (Antiminth)

15. Antifungal Agents • Requires prolonged treatment • Human cell structure resembles fungal cell structure • Action • Antifungal agents take advantage of • the slight differences of the cell structure

16. Antifungal Agents • Nystatin • Miconazole • Amphotericin B • Fluconazole

17. Antifungals: Adverse Effects • Topical: Irritation and redness • Oral: Nausea, vomiting and diarrhea • May potentiate antihistamines • IV: hepatotoxicity, renal toxicity, and phlebitis • IV drugs must be diluted and administered slowly: Amphotericin B

18. Antifungals: Nursing Considerations • IV amphotericin • Monitor vital signs every 15-30 minutes • Monitor I & O • Monitor urinalysis

19. Chapter 9 Antiseptics and Disinfectants

20. Antiseptic • An agent that kills or inhibits the growth of microorganisms • Used on skin

21. Disinfectant • An agent that rapidly destroys pathogenic microorganisms, thus preventing infection • Used on inanimate objects

22. Germicide • A general term for agents capable of destroying microorganisms

23. Action of Agents • Cell wall protein is destroyed; cell death occurs • Cell membrane permeability increases and vital contents leak out; cell death occurs • Cell components become oxidized; cell death occurs

24. Antiseptics and Disinfectants • Phenolic Agents • Alcohols and aldehydes • Acids • Iodine and iodophors • Chlorine and chlorophors

25. Antiseptics and Disinfectants • Mercury compounds • Silver compounds • Surface-active agents • Oxidizing agents • Chlorhexidine

26. Properties of the Agents • What agent are you cleaning with? • Is the offending organism killed or inactivated? • Is skin application acceptable? • How corrosive is the cleaning agent to the skin? • Does the cleaning agent have adverse effects on the skin or inanimate object?

27. Nursing Considerations • Always follow manufacturers’ directions • Properly label and store • Hand washing is critical: frequency, duration and technique is more important than nature of agent used • Clean or irrigate skin wounds before applying germicide • Protect your skin when using cleaners not intended for use on people

28. Nursing considerations • Instructions for wound care at home: • Hand washing • Safe storage of chemicals • Keep ill person’s linens separate from others in household • Don’t isolate the sick person from friends and family

29. Patient Teaching • Teach proper wound care • Involve family • Patient demonstration • written instructions • Educate: S/S of infection