SKIN LESIONS

1
SKIN/ LESIONS

• SKIN FEATURES OF PROTECTION
• Perspiration
• Sebum (oil)
• Review skin microbiota from Chapter 14
• TYPES OF LESION SEEN ON THE SKIN
• VESICLES
• BULLAE
• PAPULES
• EXANTHEM

2
BACTERIAL SKIN DISEASES

• 2 main genera are _____________
  ________________
  
• STAPHYLOCOCCAL SKIN INFECTIONS
• Gram ve cocci, 0.5-1.5 ?m in diameter
• Clusters cells do not separate completely at
  cell division
  
• 2 groups
• _______________________
• Make an enzyme able to clot blood
• Fibrin clot around the bacteria walls them off
  from host immune defenses and phagocytosis
  
• Often produce toxins, injuring tissues
• Most pathogenic COAGULASE POSITIVE
  __________________
  
• Danger in ___________ of wound infection,
• Commonly carried on the ___________
• Multiple Drug resistance is common, now only 10
  are ______________ susceptible
  
• Commonly cause __________________________

3
STAPHYLOCOCCAL DISEASES

• Conditions caused by Staphylococcus aureus
• __________ of the _____________,
• thin-walled vesicles, crusting at a later stage.
  
  
• Skin lotions containing hexachlorophene are used
  to limit the spread
  
• ________________ syndrome,
• lesion beginning around the nose and mouth
  spreads, and very large sheets of skin can be
  lost when touched.
  
• Serious disease in very young children, caused by
  a toxin,
  
• Requires vigorous antibiotic therapy
• ________________ syndrome,
• Tampon contamination, nasal surgery,
  post-childbirth
  
• Fever, vomiting, rash, then life-threatening
  shock
  
• COAGULASE NEGATIVE STAPHYLOCOCCI
• 90 of all skin forms
• Pathogenic when skin barrier is broken
  (puncture, catheterization etc.)
  

4
STREPTOCOCCAL DISEASE

• Gram ve, grow in chains
• Many in the normal microflora
• Secrete __________ and ________________
• ______________ damage red blood cells, 3 types of
  destruction are seen, bacteria are classified as
  
  
• _______________________ cause most human
  disease
  
• Over 80 immunological types known so far
• Variations in the ______________ structure
• Protein found external to the cell wall
• Contributes to strain _____________
• ______________ and _____________ to membranes
• Other important proteins adding to pathogenesis
• ________________
• Large red eruptions with thickened margins
• Accompanying fever
• Generally there is infection at other sites in
  the body
  

5
PSEUDOMONAD SKIN INFECTIONSVIRAL DISEASES

• Aerobic Gram -ve rods
• Water and soil inhabitants,
• Build-up sometimes seen in pools and hot tubs
• Nutrients / warmer water temp.
• Can cause outbreaks of dermatitis and ear
  infections
  
• Severe respiratory disease in burn victims
  immunocompromised
  
• May produce a blue-green color in pus of infected
  sites, often carried into hospitals in bunches of
  flowers or plants
  
• VIRAL SKIN DISEASES
• Many systemic viral diseases are recognized by
  effects on the skin
  
• ______________
• Stimulate uncontrolled but ___________ skin
  growths
  
• More than 50 different viruses have now been
  identified. Sometimes there is an association
  with ____________ formation
  
• Tissue containing warts must be removed for
  treatment, _______________________.
  

6
VIRAL DISEASES

• __________________
• No animal hosts plus the provision of an
  effective vaccine permitted its eradication
  
• Main risk today is laboratory containment
  breakdown, 2 labs only now possess this virus
  
• ______________________ Varicella zoster virus
• Childhood disease, 100 deaths per year
• In adults, disease is more serious
• Vesicles form, later fill with pus, rupture and
  heal
  
• Latent virus in nerve cells where they are hidden
  from immune system
  
• Lowered immune defense or stress triggers
  shingles, mostly in elderly
  
• Other viral skin/systemic diseases

7
FUNGAL SKIN DISEASES

• _________________________
• Skin environment is more favorable for fungi
• Diseases of hair, nails and outer skin
  _________________
  
• Fungi which cause them are known as __________,
  metabolize the protein _____________
  
• 3 DISEASE GROUPS
• 3 FUNGAL GENERA
• Many non-prescription drugs are effective
• Diagnosis comes from examining skin scrapings,
  most dermatophytes grow on selective media
  
• SUBCUTANEOUS, ENTRY VIA _______________
• More serious than superficial mycoses, seldom
  fatal, drinking dilute KI soln. can cure
  
• ______________ - sporotrichosis, common In
  gardeners, forms ulcers in the hands and
  lymphatic system
  

8
FUNGAL / EYE DISEASES

• OPPORTUNISTIC MYCOSIS - ________________
• Sometimes overgrows normal _____________
• Oral infections common in ____________- and
  __________________ individuals
  
• Common cause of ________________
• If it becomes systemic, it can be fatal
• DISEASES OF THE EYE
• _________________________, largely prevented by
  routine use of silver nitrate or antibiotics at
  birth
  
• __________________________ - birth canal or
  infected swimming pools
  
• ______________ - Chlamydia trachomatis
  conjunctivitis with permanent scarring, often
  caused by poor hygiene in the developing world
  
• ______________________ commonest cause of
  blindness in U.S.A.