Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings PowerPoint ® Lecture Slide Presentation prepared by Christine L. Case M I C R O B I O L O G Y a n i n t r o d u c t i o n ninth edition TORTORA  FUNKE  CASE Part A 21 Microbial Diseases of the Skin and Eyes

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Skin  Salt inhibits microbes.  Lysozyme hydrolyzes peptidoglycan.  Fatty acids inhibit some pathogens.  Defensins are antimicrobial peptides. Figure 21.1

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Mucous Membranes  Line body cavities.  Cells secrete mucus.  Some cells have cilia.

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Normal Microbiota of the Skin  Gram-positive, salt- tolerant bacteria  Staphylococci  Micrococci  Diphtheroids Figure 14.1a

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Microbial Diseases of the Skin  Exanthem: Skin rash arising from another focus of the infection.  Enanthem: Mucous membrane rash arising from another focus of the infection.

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Microbial Diseases of the Skin Figure 21.2

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Staphylococcal Skin Infections  Staphylococcus epidermidis  Gram-positive cocci and coagulase-negative  Staphylococcus aureus (golden colonies)  Gram-positive cocci and coagulase-positive  Leukocidin  Exfoliative toxin

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Staphylococcal Biofilms Figure 21.3

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Staphylococcus aureus

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Staphylococcus aureus

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Staphylococcal Skin Infections  Folliculitis: Infections of the hair follicles.  Sty: Folliculitis of an eyelash.  Furuncle: Abscess; pus surrounded by inflamed tissue.  Carbuncle: Inflammation of tissue under the skin.

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Furuncle (boil) and Carbuncle

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Staphylococcal Skin Infections  Impetigo of the newborn  Toxemia  Scalded skin syndrome  toxin caused Figure 21.4

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Streptococcal Skin Infections  Streptococcus pyogenes  hemolytic streptococci  M proteins  Prevent complement & phagocytosis Figure 21.5

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Streptococcal Skin Infections  Erysipelas  Impetigo Figures 21.6, 21.7

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Invasive Group A Streptococcal Infections  “flesh eating bacteria”  Necrotizing fasciitis Figure 21.8

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Infections by Pseudomonads  Pseudomonas aeruginosa  Gram-negative, aerobic rod  Pseudomonas dermatitis  “tub rash”

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Acne  Comedonal acne occurs when sebum channels are blocked with shed cells.

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Acne  Inflammatory acne  Propionibacterium acnes  Gram-positive, anaerobic rod  Treatment  Preventing sebum formation (isotretinoin)  Antibiotics  Benzoyl peroxide to loosen clogged follicles  Nodular cystic acne

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Inflammatory Acne Nodular Cystic Acne