4. MTB Step 3 - Skin Infections

Question 1

IMPETIGO

What are the (2) Most Common bacterial causes of Impetigo?

Answer 1

1. Streptococcus pyogenes
2. Staphylococcus aureus

**Impetigo = Most Superficial bacterial cause = Epidermal layer of skin**

Question 2

IMPETIGO

What are (2) Initial Medical Treatments for minor-moderate Impetigo caused by Strep pyogenes?

Answer 2

1. Mupirocin (Topical)
2. Retapamulin (Topical)

Question 3

IMPETIGO

What are (2) Initial Medical Treatments for severe Impetigo caused by Strep pyogenes?

Answer 3

1. Dicloxacillin (Oral)
2. Cephalexin (Oral)

Question 4

IMPETIGO

What are (2) Initial Medical Treatments for severe Impetigo caused by MRSA?

Answer 4

1. TMP/SMX (Bactrim)
2. Doxycycline

Question 5

IMPETIGO

What is the Treatment for Severe Impetigo caused by Strep pyogenes in a patient with a Rash Allergy to Penicillin?

Answer 5

Cephalexin

Question 6

IMPETIGO

What are the (7) possible Treatments for Severe Impetigo caused by Strep pyogenes in a patient with an Anaphylaxis Allergy to Penicillin?

Answer 6

Anaphylaxis Allergy = Vancomycin, Linezolid, Clindamycin, Doxycycline, Telavancin, TMP/SMX, Daptomycin

Question 7

ERYSIPELAS

What is the Most Likely Bacterial Cause of Erysipelas?

Answer 7

Streptococcus pyogenes (Group A Strep)

Question 8

ERYSIPELAS

What are (2) Clinical Manifestations of Erysipelas, and what is the MOA for these?

Answer 8

1. Bright Red skin
2. Hot skin

MOA = dilation of the capillaries of the Dermis due to locally released inflammatory mediators.

Question 9

ERYSIPELAS

What are the (2) Best INITIAL (empiric) Treatments for Clinically (solely based on observation; empirically) Diagnosed Erysipelas?

Answer 9

1. Dicloxacillin (Oral)
2. Cephalexin (Oral)

Question 10

ERYSIPELAS

What is the Treatment for culture diagnosed Streptococcus pyogenes (Group A Strep) Erysipelas?

Answer 10

Penicillin VK

Question 11

CELLULITIS

What are the (2) Most Likely Bacterial Causes of Cellulitis?

Answer 11

1. Staphylococcus aureus
2. Streptococcus pyogenes

Question 12

CELLULITIS

What are (4) Clinical Manifestations of Cellulitis?

Answer 12

1. Warm
2. Red
3. Swollen
4. Tender skin

**likely to present in the arm or leg but can present in any skin**

Question 13

CELLULITIS

If presented with a possible case of Cellulitis in a Leg, what condition should be Ruled Out prior to treatment, and which diagnostic method should be used?

Answer 13

Lower Extremity Doppler to exclude DVT.

Question 14

CELLULITIS

What are (3) Antibiotics used to treat Minor Cases of Cellulitis?

Answer 14

1. Dicloxacillin (Oral)
2. Cephalexin (Oral)
3. Amoxicillin/Clavulanate (Oral)

Question 15

CELLULITIS

What are (4) Antibiotics used to treat Severe Cases of Cellulitis?

Answer 15

1. Oxacillin (IV)
2. Nafcillin (IV)
3. Cefazolin (IV)
4. Ampicillin/Sulbactam (IV)

Question 16

CELLULITIS

What are the (2) Medications which may be used to treat Cellulitis in a patient with a Rash Allergy to Penicillin?

Answer 16

Cephalosporins:

1. Cefazolin
2. Ceftaroline

Question 17

CELLULITIS

What are the (2) Medications which may be used to treat Minor Cases of Cellulitis in a patient with an Anaphylaxis Allergy to Penicillin?

Answer 17

1. TMP/SMX
2. Clindamycin

Question 18

CELLULITIS

What are the (3) Medications which may be used to treat Severe Cases of Cellulitis in a patient with an Anaphylaxis Allergy to Penicillin?

Answer 18

1. Vancomycin
2. Linezolid
3. Daptomycin

Question 19

FOLLICULITIS < FURUNCLES < CARBUNCLES < BOILS

What is the Most Likely Bacterial Cause for Folliculitis, Furuncles, Carbuncles, and Boils?

Answer 19

Staphylococcus aureus skin infections beginning in the Hair Follicle:

• Folliculitis = smallest, most minor
• Furuncles = small, minor
• Carbuncles = medium, moderate
• Boils = large, moderate-severe
• Abscess = largest, most severe

Question 20

FOLLICULITIS < FURUNCLES < CARBUNCLES < BOILS

What are (3) Antibiotics used to treat Minor Cases of these Skin Infections?

Answer 20

1. Dicloxacillin (Oral)
2. Cephalexin (Oral)
3. Amoxicillin/Clavulanate (Oral)

**Larger Infections** (eg, Boils, Abscess) **respond to drainage**

**Same Tx as for Cellulitis**

Question 21

FOLLICULITIS < FURUNCLES < CARBUNCLES < BOILS

What are (4) Antibiotics used to treat Severe Cases of these Skin Infections related to pimples?

Answer 21

1. O xacillin (IV)
2. N afcillin (IV)
3. C efazolin (IV)
4. A mpicillin/Sulbactam (IV)

O.N.C.A.

**Same Abx’s as for Cellulitis**

Question 22

FOLLICULITIS < FURUNCLES < CARBUNCLES < BOILS

What are the (2) Medications which may be used to treat these Skin Infections in a patient with a Rash Allergy to Penicillin?

Answer 22

Cephalosporins:

1. Cefazolin
2. Ceftaroline

Question 23

FOLLICULITIS < FURUNCLES < CARBUNCLES < BOILS

What are the (2) Medications which may be used to treat Minor Cases of these Skin Infections in a patient with an Anaphylaxis Allergy to Penicillin?

Answer 23

1. TMP/SMX
2. Clindamycin

Question 24

FOLLICULITIS < FURUNCLES < CARBUNCLES < BOILS

What are the (3) Medications which may be used to treat Severe Cases of these Skin Infections in a patient with an Anaphylaxis Allergy to Penicillin?

Answer 24

1. Vancomycin
2. Linezolid
3. Daptomycin

Question 25

**FUNGAL INFECTIONS OF SKIN AND NAILS** What are (**3**) _Common Manifestations_ of ***Fungal Infections*** on the **SCALP**?

Answer 25

1. **Severe Itching** 2. **Dandruff** 3. **Bald Patches**

Question 26

**FUNGAL INFECTIONS OF SKIN AND NAILS** What are (**4**) _Common Manifestations_ of ***Fungal Infections*** on the **NAILS**?

Answer 26

1. **Thickened** 2. **Yellow** 3. **Cloudy** 4. **Fragile** and/or **Broken**

Question 27

**FUNGAL INFECTIONS OF SKIN AND NAILS** What is the _Best Test_ to *Diagnose **Fungal Infections*** of the **Skin** and **Nails**?

Answer 27

**KOH Preparation** ***Procedure:*** 1. Scrape the Skin/Nail 2. Place scraping on slide with KOH + Acid 3. Heat the slide ***\*\*Epithelial Cells will dissolve and leave the Fungal forms behind, visible on the slide, due to the Chitin in the Fungal Cell Wall\*\****

Question 28

**FUNGAL INFECTIONS OF SKIN AND NAILS** What are (**7**) _Medicinal Treatments_ for ***Fungal Infections*** of the Skin **NOT** involving the *Hair or Nails*?

Answer 28

1. **Clotrimazole** (Topical) 2. **Miconazole** (Topical) 3. **Ketoconazole** (Topical) 4. **Econazole** (Topical) 5. **Terconazole** (Topical) 6. **Nystatin** (Topical) 7. **Ciclopirox** (Topical)

Question 29

**FUNGAL INFECTIONS OF SKIN AND NAILS** What are (**3**) _Medicinal Treatments_ for ***Fungal Infections*** of the Skin **Involving** the *Hair or Nails*?

Answer 29

**_Oral Medications:_** 1. **Terbinafine:** *AEs = Increased LFTs* 2. **Itraconazole** 3. **Griseofulvin** *(for Tinea Capitis): Has Less Efficacy than either _Terbinafine_ or _Itraconazole_*.