Bacterial Diseases

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Bacterial Diseases
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Pathogenicity

• the state of producing or being able to produce
  pathological changes and disease

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Staphylococcus

• a genus of gram-negative, nonmotile,
  opportunistic bacteria which tend to aggregate in
  irregular, grape-like clusters

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Readings Question 1

• Staphylococcus aureus is the most pathogenic of
  the staphylococci. What are its toxins capable
  of doing? What enzymes does it produce, and what
  is their known effect?

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Staphylococcal Food Poisoning

• caused by ingesting an enterotoxin
• high resistance to heat, drying and radiation,
  and high osmotic pressures
• inhabitant of nasal passagescontaminates the
  hands..readily enters food
• mechanical vectors
• mayonnaise, cream sauces

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Skin and Wound Infections

• Sty infected follicle of an eyelash

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Skin and Wound Infections (contd)

• Pimple infected hair follicle
• Abscess more serious hair follicle infection
• furuncle/boil superficial
• carbuncle deeper
• Risk of underlying tissues becoming infected
• Toxemia toxins circulate

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Scalded Skin Syndrome
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Toxic Shock Syndrome

• S. aureus growth associated with the use of a new
  type of highly absorbent vaginal tampon
• swell with menstrual fluids and adhere to the
  vagina
• tears in the vaginal wall

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Streptococcus

• spherical shaped bacteria occurring in chains
• What are the implications for the embalmer when
  dealing with saprophytes?

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Streptococcus pneumoniae( pneumococcus)

• gram-positive ovoid bacterium
• cell pairs surrounded by capsule
• common cause of
• 1) lobar pneumonia
• 2) meningitis
• 3) otitis media

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Lobar Pneumonia

• Readings question 2
• What is lobar pneumonia, and how is it
  characterized?
• What are some of the predisposing conditions for
  this disease?
• penicillin and fluoroquinolones

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Meningitis

• 70 of the population are healthy carriers
• Gram-positive encapsulated diplococcus
• Leading cause of bacterial meningitis
• Most cases between 1 month and 4 years
• Broad-spectrum cephalosporins
• CSF obtained by a spinal tap
• Vaccine Pneumococcal Conjugated Vaccine

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Otitis Media

• 85 before 3 years of age (Eustachian Tubes)

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Streptococcus pyogenes

• Scarlet Fever streptococcal pharyngitis
• Septic Sore Throat respiratory secretions
• penicillin
• Puerperal Sepsis Childbirth/Childbed Fever
• Rheumatic Fever arthritis and fever
• 50 inflammation of the heart
• penicillin
• Syndenhams chorea

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Neisseria

• gram-negative cocci that inhabit the mucous
  membranes

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Readings Question 3

• One of the most common communicable diseases in
  the United States is gonorrhea, an STD caused by
  Neisseria gonorrhoeae. How does it attach to the
  tissues? How does it spread? What is its only
  natural host? What is its most common symptoms?
  When do symptoms appear?

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Gonorrhea

• leukocytes
• men single unprotected exposure- 20-35
• women 60-90
• Men urethra
• sterility
• vas deferens

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Women

• insidious
• cervix
• abdominal pain PID
• Men and Women
• Untreated gonorrhea can disseminate and become a
  serious, systemic infection.

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Opthalmia Neonatorum

• antibiotics/silver nitrate

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Antibiotic Resistance

• penicillin
• fluorquinolone antibiotics
• frequent coinfection with chlamydia
• include antichlamydial in treatment
• tetracycline
• Diagnosis ELISA- detects N. gonorrhoeae

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Readings Question 4

• Gonorrhea is a common cause of pelvic
  inflammatory disease in women. What are its
  signs and symptoms? What is epididymitis?

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PID

• 1 in 10 women
• 1 in 4 serious complications
• coinfection with chlamydial bacteria
• barrier contraceptives with spermicides
• salpingitis most serious form
• ectopic/tubal pregnancy
• Treatment gonococcus and chlamydia

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Neisseria meningitides(meningococcus)

• aerobic, gram-negative bacteria with a capsule,
  pili, and production of endotoxins
• endotoxins are primarily responsible for symptoms
• most distinguishing feature is the rash that does
  not fade when pressed

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Meningococcus Rash

• Spots do not blanch when pressed with the glass.

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Meningococcus Rash

• Septicemic Rash

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Meningococcal Meningitis

• typically begins with a throat infection which
  leads to bacteremia, and eventually meningitis
• generally occurs in children under 2 years
• residual damage
• sporadic outbreaks
• vaccine
• penicillin and cephalosporin

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Menningococcemia

• Gangrene of the hand of a 4 month old.

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Clostridium

• obligate anaerobes
• rod-shaped cells that contain endospores
• Clostridium botulinum botulin

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Readings Question 5

• Clostridium tetani causes what bacterial
  infection? Describe the characteristics of this
  microbe. Where is it found? What are its
  symptoms, and what causes them?

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Gas Gangrene
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Gas Gangrene
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Readings Question 6

• Clostridium perfringens is the causative agent of
  a postmortem condition known as tissue gas.
• List 3 things that may result in this condition
  in the decedent.
• List 7 conditions that predispose the decedent to
  tissue gas formation.

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Food Intoxication

• Clostridium perfringens Gastroenteritis one of
  the more common forms of food poisoning in the
  United States
• improper handling of meat during the slaughtering
  of animals
• 2 main causes 1) keeping foods warm for
  more than 20 minutes
• 2) inadequate refrigeration

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Corneybacterium

• Diptheria caused by Corneybacterium diptheria
• 2 forms
• 1) respiratory
• 2) cutaneous

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Respiratory Diptheria

• Begins with a sore throat, followed by general
  malaise and swelling of the neck.
• DTaP vaccine
• antibiotics used in
• conjunction with
• antitoxin

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Cutaneous Diptheria

• C. diptheria infects the skin
• minimal systemic circulation of the toxin
• slow-healing ulcerations covered by a gray
  membrane

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Reading Question 7

• Tularemia/Rabbit Fever is a zoonotic disease
  caused by the bacterium Francisella tularensis.
  What are the characteristics of this parasite?
  How can it enter the body? What are the signs
  associated with this disease?
• Proliferation can lead to sepsis.
• Streptomycin is the antibiotic of choice.

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Salmonella typhi

• most virulent strain and causes typhoid fever
• pathogen not found in animals
• spread only in the feces of other humans
• S. typhi multiply within phagocytic cells,
  disseminated into multiple organs
• phagocytic cells lyse
• high fever and headache are 1st symptoms
• diarrhea in 2nd or 3rd week

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Typhoid Fever

• 350 500 annual cases in the United States
• 70 foreign travel
• worldwide
• 16 million annual cases
• 600,000 deaths/year
• cephalosporins
• 1909 newspaper illustration