Study Guide for Skin and Soft Tissue Infections

 Name: ________________________            Date: _______________

  1. What organisms are normal flora of the skin?  

 

  1. What conditions do normal skin flora need to tolerate to survive on the skin for extended periods of time?

 

  1. What does colonizing organisms mean?

 

  1. What is the specimen of choice to assist in isolating a pathogen in skin and soft tissue infections and eliminating colonizing bacteria?

 

  1. What are you looking for in a direct Gram stain or in the gross appearance of exudate, which would be suggestive of actinomycetes or fungi?

 

  1. Complete the following chart:
Infection

Definition

Caused by What Organism(s) Predisposing Factors or Types of Patients Other Conditions Contributing to the Infection
Impetigo

 

       
Folliculitis

 

       
Furuncles and Carbuncles
       
Cellulitis

 

       
Erysipelas

 

       
Paronychia

 

       
Erysipeloid

 

       
Erythrasma

 

       
Myonecrosis (Gas Gangrene)
       

 

  1. Complete the following chart relating to secondary bacterial skin infections:

Skin Infection

Major Pathogens

Clean surgical wound infection

Colon-contaminated surgical wound infections

IV infusion sites

Soil-contaminated, trauma wound infection

Fresh water contaminated trauma wound infection

Salt water contaminated trauma wound infection

Dog and Cat Bites

Ducubitus ulcer

Foot ulcers in diabetics

Burns

 

  1. Briefly discuss skin infections relating to the following:
  • Cutaneous diphtheria  

  • Melioidosis and glanders

  • Francisella tularensis  

  • Mycobacterial Skin Infections  

  •  Actinomyces & Norcardia

  1. What in the direct Gram stain of the exudate is particularly useful to the physician?

 

  1. Since culture is still the most sensitive method of diagnosing cutaneous infections, what media should be used?

 

  1. What organism and infection would be treated empirically with penicillin and would not require a susceptibility test?

 

 

  1. Discuss the following types of cutaneous infections.
  •  Rickettsia infections such as Rocky Mountain Spotted Fever

 

  • Spirochetal infections

  • Syphilis  

  • Yaws, Pinta, and Bejel  

  • Lyme Disease  

  • Viral skin disease

  • Warts  

  • Varicella and Zoster  

  • Herpes Simplex  

  • Other Herpesviruses - Cytomegalovirus
     

  • Fungal diseases

  • Dermatophytoses

  • Candidasis  

  • Subcutaneous Mycoses
     

  • Sporotrichosis  

  • Systemic Mycotic Infections  

 

 

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Clinical Microbiology Syllabus