Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings PowerPoint ® Lecture Slide Presentation prepared by Christine L. Case Microbiology B.E Pruitt & Jane J. Stein AN INTRODUCTION EIGHTH EDITION TORTORA FUNKE CASE Chapter 21, part A Microbial Diseases of the Skin and Eyes
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Skin Salt inhibits microbes Lysozyme hydrolyzes peptidoglycan Fatty acids inhibit some pathogens Figure 21.1
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Line body cavities Epithelial cells attached to an extracellular matrix Cells secrete mucus Some have cilia Mucous Membranes
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Gram-positive, salt- tolerant bacteria Staphylococci Micrococci Diphtheroids Normal Microbiota of the Skin Figure 14.1a
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Exanthem Skin rash arising from another focus of infection Enanthem Mucous membrane rash arising from another focus of infection Microbial Diseases of the Skin
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Microbial Diseases of the Skin Figure 21.2
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings S. epidermidis Gram-positive cocci, coagulase-negative Staphylococcus aureus Gram-positive cocci, coagulase-positive Leukocidin Exfoliative toxin Staphylococcal Skin Infections
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Staphylococcal Skin Infections Figure 21.3
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Staphylococcal Skin Infections Folliculitis Infections of hair follicles Sty Folliculitis of an eyelash Furuncle Abscess; pus surrounded by inflamed tissue Carbuncle Inflammation of tissue under the skin
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Staphylococcal Skin Infections Impetigo of the newborn Toxemia Scalded skin syndrome Toxic shock syndrome Figure 21.4
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Streptococcus pyogenes Group A beta- hemolytic streptococci M proteins Streptococcal Skin Infections Figure 21.5
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Erysipelas Impetigo Streptococcal Skin Infections Figure 21.6, 7
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Streptokinases Hyaluronidase Exotoxin A, superantigen Cellulitis Necrotizing fasciitis Invasive Group A Streptococcal Infections Figure 21.8
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Pseudomonas aeruginosa Gram-negative, aerobic rod Pyocyanin produces a blue-green pus Pseudomonas dermatitis Otitis externa Post-burn infections Infections by Pseudomonads
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Calculate the relative risk to determine the most likely source of Pseudmonas dermatitis ExposureExposedNot Exposed (a) Have Rash (b) No Rash(c) Have Rash (d) No Rash Restaurant Arcade10696 Swimming pool Exercise room Hot tub e = a a + b f = c c + d Relative Risk = efef
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings What was the mostly likely source of this outbreak of Pseudmonas dermatitis? ExposureRelative Risk Restaurant1.24 Arcade1.04 Swimming pool6.14 Exercise room1.29 Hot tub9.90
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Comedonal acne Occurs when sebum channels are blocked with shed cells Inflammatory acne Propionibacterium acnes Gram-positive, anaerobic rod Treatment: Preventing sebum formation (isotretinoin) Antibiotics Benzoyl peroxide to loosen clogged follicles Visible (blue) light (kills P. acnes) Nodular cystic acne Treatment: isotretinoin Acne
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Papillomaviruses Treatment: Removal Imiquimod (stimulate interferon production) Interferon Warts