Fungal and Parasitic Infections

anti-fungal nemonic

AAPE

Drug Class: Allylamines

• MOA

• example

• block ergosterol syn → disrupt fungal membrane

• Terbinafine

Drug Class: Azoles

• MOA

• example

• inhibit ergosterol synthesis → disrupt fungal membrane

• Fluconazole

Drug Class: Polyenes

• MOA

• example

• bind ergosterol → pores → fungal death

• Amphotericin B (systemic), Nystatin (local)

Echinocandins

• MOA

• example

• Inhibit B-1,3 D glucan → block fungal cell wall syn

• Caspofungin

Dematophtye infections are _________

Examples: ________________

Transmission: ___________

Treatment: ___________, _____

superficial

athlete’s foot, ringworm, jock itch, scalp infections, nail fungus

direct contact

topicol antifungals (terbinafine), oral antifungals for severe/nail

Endemic Mycoses are caused by fungi in _____________

Examples: ______, ________, _______

Transmission: ______

Treatment: ________, ________

specific regions

Histoplasmosis *bat/bird droppings, Coccidioidomycosis *dry, Blastomycosis *moist

Inhalation

Fluconazole, Amphotericin B

Opportunistic fungi cause mild symptoms in ________, but serious infections in ______

Examples: ______, _____, ______, ________

Transmission:

Treatment: ____, _____, ________, ______, ______

immunocompetent; immunocompromised

Candidiasis*, Aspergillosis*, Cryptococcois*, Pneumocystis pneumonia (PCP)*

Environmental exposure to spores or overgrowth of normal flora

Nystatin (oral thrush), Amphotericin B, fluconazole, TMP-SMX (PCP), Caspofungin

Invasive/Systemic fungal infections invade _____ and spread through the _______

Examples: ______, _______, ______, ______

Treatment:

organs; bloodstream

Invasive candidas*/aspergillosis*, disseminated cryptococcosis*/histoplasmosis*

aggressive systemic antifungals (Amph B, caspofungin, -azoles)

Terbinafine *Allylamine

• Indications

• Nurse

2 forms

• Indications: Dermatophyte Infections, Onychomycosis

• Nurse: liver function test *oral, taste disturbance/signs of liver damage

Oral + Topical

What is Onychomycosis and therapy does it require?

fungal nail infections

requires oral terbinafine

Fluconazole *Azole

• Indications

• ADR

• Nurse

2 forms

• Ind: Candida + invasive, Cryptococcus *bird, coccidioidomycosis *dry soil

• ADR: inhibits CYP450, SJS/TENS, QT prolongation, hepatotoxicity

• DI, electrolytes (K+), hepatotoxicity

IV or oral

Nystatin *Polyene (local)

• Indications

• Nurse

• Ind: oral/vaginal thrush (candida infections)

• Oral: after meals, swish then swallow, avoid eating/drinking for 30 mins

  • Topical: apply 2-3 times daily, powder if moist or else cream

Amphotericin B *Polyene (systemic)

• Indications

• ADR

• Nurse

2 forms

• Ind: systemic candida (infections)

• ADR: infusion interactions (hypotension), EVERY toxicity u can think of

• Renal function (BUN, creatinine), Mg/K+, infusion reactions, hydration

IV *phlebitis or PO

What is phlebitis and what drug is it an ADR of?

inflammation of vein; Amph B

Caspofungin *Echinocandin (systemic)

• Indication

• ADR

• Nurse

1 form

• Ind: invasive candida, aspergillosis

• ADR: infusion rxn: hypotension, chills, fever

• LFT, IV slowly

IV

Major Intestinal Protozoal Infections

• Amebiasis

• giardiasis

• cryptospordiosis

Amebiasis - Entameoba histolytica

• Treatment

• bloody diarrhea

• may cause liver abscess

• Treatment: metronidazole/tinidazole

Giardiasis - Giardia lamblia

• Treatment

• greasy stools

• associated with contaminated water

• Treatment: metronidazole/tinidazole

Cryptosporidiosis

• Cause

• Treatment

• watery diarrhea

• Cause: oral-food borne, contaminated water

• Treatment: nitazoxanide + hydration

Trichomoniasis

• Transmission:

• Symptoms:

• Treatment:

• Transmission: sexual contact

• Symp: vaginal discharge, dysuria

• Treatment: metronidazole/tiniazole

Malaria (plasmodium infection)

• pathology

• symptoms

• diagnosis

• treatment

• pathology: parasite → infect liver → RBC → immune response

• symp: fever, chills, sweats, headache, fatigue

• diagnosis: blood smear

• treatment: chloroquine, ACT (therapy)

Chloroquine *antimalarial

• MOA

• ADR:

• Contra:

• Nurse

• MOA: toxic heme accumulates → paraside dies

• ADR: CNS and cardiac toxicity (high dose), ocular toxicity

• Contra: G6PD deficiency

• Vision changes, take with food, hemolysis in G6PD deficiency

Toxoplasmosis *Teratogenic

• Transmission:

• Patho:

• Symptoms:

• Treatment

• Transmission: cat feces, undercooked meat, congenital transmission

• Patho: parasite → blood → brain/muscle/retina → inflammation + necrosis

• Sympt: asymptomatic in healthy. congenital: encephalitis, ocular disease

• Treatment: pyrimethamine + sulfadiazine + folinic acid

Pyrimethamine *antiprotozoal

• MOA

• Indications:

• ADR:

• Contra:

• Nurse

• MOA: inhibit folic acid syn → no DNA synthesis

• Ind: Toxoplasmosis, malaria

• ADR: bone marrow suppression

• Contra: folate deficiency, pregnancy

• CBC, give leucovorin for toxicity

Helminth infections

• patho:

• physical findings:

• diagnosis:

• treatment:

• patho: enter via food/soil/water → intestines/tissues → blood/nutrition loss, inflammation → tissue damage

• physical findings: anemia, malnutrition, eosinophilia (inc WBC)

• diagnosis: CT/MRI

• treatment: Mebendazole

Mebendazole *anti-helminthic

• MOA

• Nurse

• MOA: blocks glucose → death

• Chew tablet

Ectoparasitic (scabies/lice) infections

• patho:

• symptoms + signs

• diagnosis:

• Treatment:

• patho: parasite lives on skin → feeds on blood/skin → hypersensitivity rnx

• symptoms: itching (rash/sores) signs: redness, eggs

• Diagnosis: skin scraping

• Treatment: ivermectin or permethrin

Ivermectin *Avermectin

• MOA

• Indications

• Contra

• Nurse

• MOA: binds chloride channel → paralysis + death

• Ind: scabies (oral for severe), head lice

• Contra: pregnancy

  • Single oral dose: 200 mcg/kg, repeat 1-2 weeks

Permethrin *antiparasitic

• MOA

• Indications:

• Nurse

• MOA: disrupts parasite sodium channels → death

• Ind: scabies + head lice

• Nurse: topicol. scabies: apply to body, wash after 8-14 hrs. lice: apply to scalp, repeat in 7-10 days