Fungal Infections - Block 3

Question 1

Ex of dermatophytes?

Answer 1

1. Trichophyton
2. Microsporum
3. Epidermophyton

Question 2

Types of Yeast?

Answer 2

1. Candida
2. Cryptococcus neoformans

Question 3

Types of mold?

Answer 3

Aspergillus

Question 4

Types of dimorphic?

Answer 4

1. Histoplasma
2. Bastomyces
3. Coccidioides
4. Paracoccidioides
5. Sporothrix

Question 5

Stypes of antimicrobial resistant fungi?

Answer 5

1. Aspergillus (Azole)
2. Candida (fluconazole)
3. Candida auris (fluconazole)
4. Ringworm

Question 6

Can topical azoles be used for pregnancy?

Answer 6

Yes

Question 7

Terbinafine

MOA

Answer 7

Disrupts synthesis of ergosterol and penetrates to keratin precursor cells (fungicidal)

Question 8

Griseofulvin

MOA

Answer 8

Prevents fungal cell division and provides good penetration to superficial sites due to transfer of drug cia sweat and trans epidermal fluid loss

Question 9

Ciclopirox

MOA

Answer 9

Topical lacquer that degrades peroxides within the fungal cells

Question 10

Nystatin

MOA, Idication

Answer 10

MOA: Alters fungal cell membrane leading to leakage of cell -> cell death
Indication: Oral candidiasis or thrush

Question 11

Zinc oxide

MOA

Answer 11

Provides physical barrier to water absorption

Question 12

Selenium sulfide

MOA

Answer 12

Reduction in the turnover of epidermal cells

Question 13

What are the presentations of Oral candidia? Diagnosis?

Answer 13

Sx: Dysphagia, abnormal odor, dry mouth, abnormal taste
Diagnosis: White plaque that leave an inflamed or bleeding base when scraped off

Question 14

TYpes of thrush tx?

Answer 14

Acute: 7-14 days
Suppression: not recommended

Question 15

Tx for Oral Candida?

Answer 15

Fluconazole
Nystatin
Miconazole
Clotrimazole

7-14 days

Question 16

Presentations of esophageal candida? Diagnosis?

Answer 16

1. Can be asymptomatic
2. AIDS defining illness (CD4 <100)

Diagnosis: Endoscopy

Question 17

Tx for Esophageal Candidiasis?

Answer 17

Prophylaxis: Fluconazole, itraconazole
Acute: Fluconazole for 14-21 days
Resistnat: Itraconazole oral solution

Question 18

Vulvovaginal Candidiasis presentation and diagnosis?

Answer 18

Sx: discharge with little to no odor, pruritis, erythema
Diagnosis:
* Uncomplicated: clincal exam, pH (4-4.5), wet mount
* Complication: reccurent (>4 episodes/wr), severe VVC

Question 19

Vulvovaginal Candida Tx? Pregnancy?

Answer 19

Uncomplicated:
* Miconazole 2% x 3 days
* Fluconazole PO 1 dose

Complicated:
* Miconazole 2% for 7-14 days
* Fluconazole PO for 3 days and 2 doses

Topical azole x 7 days for pregnancy

Question 20

Tx for diaper dermatitis?

Answer 20

Nonpharm: Skin care, choice of diaper
Pharm:
* Topical barrier: petrolatum, zinc oxide
* Topical antifungal: nystatin, clotrimazole, miconazole, ketoconazole BID for 2 weeks

Question 21

Presentation of Intertriginous Dermatitis (Intertrigo)?

Answer 21

Condition of skin folds causes by moisture, friction and absence of air circulation
* Burning, tenderness, prutitus, fissuring

Question 22

Tx for Intertriginous Dermatitis (Intertrigo)?

Answer 22

Topical agents 1st line: Ketoconzale, Clotrimazole, Miconazole
PO: Fluconazole for 4 wks

Question 23

What is the difference between tinea barbae and capitis?

Answer 23

Barbae: affects beard and mustache
Capitis: Multiple scaly and/or crusted patches and/or plaque affecting scalp or beard

Question 24

Tx for tinea barbae/capitis?

Answer 24

Terbinafine PO for 4 wks

Question 25

Presentation of tinea corporis/cruris

Answer 25

Erythematous plaque with raised leading edge and scaling clearance at the center of a lesion with scattered nodules: **Corporis:** body **Cruris:** scrotum

Question 26

Tx for Tinea Corporis/Tinea Cruris?

Answer 26

**Topical:** Terbinafine 1% cream BID for 3-4 wk **Systemic (failure of topical):** Terbinafine PO QD for 2-4 wks

Question 27

Presentation of tinea pedis

Answer 27

1. Interdigital (in between toes) 2. Moccasin styles (heel, soles, lateral aspects of feet) 3. Vesiculobullous (instep)

Question 28

Tx for tinea pedis?

Answer 28

**Topical (preferred):** Terbinafine 1% cream QD 2-4 wks **Systemic:** Terbinafine PO QD 2 wk **Nonpharm:** Dry cotton socks, loose fitting shoes, drying powder, and drying feet

Question 29

Presentation and diagnosis of Tinea Unguium/Onychomycosis?

Answer 29

Separation of nail plate, thickening, discoloration, destruction of nail plate **Diagnosis:** KOH prep, fungal culture, nail clippings, nail biopsy

Question 30

Presenation and diagnosis of Tinea versicolor (Pityriasis versicolor)?

Answer 30

**Presentation:** Superficial infection caused by yeast * Hypopigmented and/or hyperpigmented patched with very fine scaling affecting sebum-rich areas **Diagnosis:** Physical exam

Question 31

Tx for Tinea Unguium/Onychomycosis Treatment?

Answer 31

**Systemic:** Terbinafine PO QD for 6 wks (fingernails) or 12 wks (toenails) - avoid in liver dx **Topical:** Efinaconazole 10% nail lacquer QD for 48 wks

Question 32

RF of thrush?

Answer 32

Age, IC

Question 33

RF of vulvovaginal candida?

Answer 33

IC, Uncontrolled diabetes, debilitation, pregnancy, recurrent infection

Question 34

RF of diaper rash?

Answer 34

Infrequent diaper changing, infants with diarrhea or chronic stooling, ABX use

Question 35

RF of intertriginous dermatitis?

Answer 35

1. Bedridden 2. Obesity 3. Incontinence 4. Poor hygiene 5. Hyperhidrosis 6. Immune def

Question 36

RF of Tinea versicolor (Pityriasis versicolor)?

Answer 36

1. Tropical climate/warm weather 2. Malnutrition 3. PO contraceptives 4. Systemic CS 5. Immunosuppresants 6. Hyperhidrosis

Question 37

Tinea vesicolor tx?

Answer 37

**Topical (first line):** Zinc pyrithione shampoo scrubbed onto the affected areas using a mildly abrasive sponge and rinsed off in 3-5 minutes QD x 1-4 wks **Systemic:** FLuconazole PO QW 2-4 wks

Question 38

RF for invasive fungal infection?

Answer 38

1. IC host 2. CD4 count <200 cells/mm3 3. Neutropenia (ANC 500/mm3 or less) 4. Nosocomial infections

Question 39

Antifungals for systemic infections?

Answer 39

1. Amphotericin B 2. Flucytosine 3. Azole 4. Echinocandins 5. Terbinafine

Question 40

What are the formulations of amphotericin B?

Answer 40

1. Conventional/Amphotericin B deoxycholate (Fungizone IV) 2. Liposomal (AmBisome)

Question 41

ADR of amphotericin?

Answer 41

1. Infusion related rx 2. Renal toxicity 3. Electrolyte Abnormalities due to intracellular leakage and tubular defects

Question 42

Dosing of amphotericin B in obesity?

Answer 42

If using Adjusted Body Weight to dose, a **max of 100 kg** is suggested. If using Actual Body Weight to dose, a **max dose of 600 mg** is recommended

Question 43

ADR of azoles?

Answer 43

Visual disturbance, QTc prolongation, hepatotox **Fluconazole:** avoid in pregnacy

Question 44

DDI of azoles?

Answer 44

Inhibitors of CYP2D6, 2C9, 2C19, 3A4, 3A5, and 3A7 Fluconazole has the least amount of interactions

Question 45

Itraconazole counseling?

Answer 45

Absorption is dependent of gastric pH -> avoid PPI, H2RAs, antiacids

Question 46

ADR of echocandin?

Answer 46

Peripheral edema, febrile neutropenia

Question 47

DDI of echinocandiN?

Answer 47

Capsofungin and Micafungin are substrates and inhibitors of CYP3A4 **Hepatic dosing:** capsofungin

Question 48

CI and obesity dosing of echinocandin?

Answer 48

**CI:** pregancy **Obesity dosing:** Micafungin: for patients weighing over 115kg, increase dose to 200 mg

Question 49

ADR of flucytosine?

Answer 49

Nephrotoxicity, hepatotoxicity, bone marrow suppression

Question 50

Dosing of flucytosine?

Answer 50

**Renal dosing:** based on GFR **Obesity:** Use IBW **Requires therapeutic drug monitoring:** 30-80mcg/mL

Question 51

Presentation and diagnosis of Disseminated Candidiasis/Candidemia?

Answer 51

**Sx:** fever, sx nonspecific **Diagnosis:** histopathology/fungal cultures, blood cultures, serum (1,3) beta-D-glucan, T2 Candida panel

Question 52

RF of Disseminated Candidiasis/Candidemia?

Answer 52

neutropenia, prolonged hospitalization, central venous catheters, major surgery, broad-spectrum ABX, TPN

Question 53

Tx for Disseminated Candidiasis/Candidemia?

Answer 53

**Preferred:** Capsofungin, anidulafungin, micafungin **Azole (alternative):** Fluconazole, Voriconazole **Azole and echinocandin resistance:** Liposomal amphotericin B 3-5 mg/kg QD

Question 54

Presentation and diagnosis of aspergillosis?

Answer 54

**Acute invasive pulmonary:** cough, hemoptysis, pleuritic chest pain, shortness of breath **Chronic pulmonary:** mild symptoms Extrapulmonary invasive: skin lesions, sinusitis, or pneumonia, can disseminate and often rapidly fatal **Aspergillosis in sinuses:** fever, rhinitis and headache; can have necrotic lesions, palatal or gingival ulcerations, sinus thrombosis, or pulmonary or disseminated lesions **Aspergillomas:** often asymptomatic, may cause mild cough and/or hemoptysis **Diagnosis:** CT chest/Xray

Question 55

Tx for aspergilosis?

Answer 55

Voriconazole PO

Question 56

Presentation and diagnosis of histoplasmosis?

Answer 56

**Presentation:** * **Acute primary:** resembles a cold and/or pneumonia * **Chronic cavitary:** pulmonary lesions and worsening respiratory status * **Progressive disseminated:** hepatosplenomegaly, lymphadenopathy, bone marrow involvement, oral/gastrointestinal ulcerations **Diagnosis:** Chest X-ray

Question 57

Tx for Acute primary histoplasmosis?

Answer 57

If infection does not resolve after 1 month: * Itraconazole 200 mg PO three times daily x 3 days, then twice daily x 6-12 weeks

Question 58

Tx for chronic cavitary histoplasmosis?

Answer 58

**Itraconazole** 200 mg PO three times daily x 3 days, then twice daily for 12-14 months

Question 59

Tx for severe disseminated histoplasmosis?

Answer 59

Liposomal amphotericin B 3 mg/kg IV daily until clinically stable, then itraconazole 200 mg PO three times daily x 3days, then twice daily x 12 months after they become: * Afebrile * AIDS patients are given itraconazole indefinitely to prevent relapse or until CD4 count is > 150