MICRO EXAM 2 PART 1

Streptococcus Agalactiae

• Beta-hemolytic means complete hemolysis
• Group B Streptococcus (GBS) can colonize the upper respiratory and genitourinary tracts asymptomatically

Streptococcus Agalactiae Disease and Treatment

• The disease is most serious in neonates, particularly in infants
• GBS can cause bacteremia, pneumonia, or meningitis in neonates
• Urinary tract infections can occur in pregnant women, including postpartum infections
• Pregnant women should be screened for S. agalactiae infection before birth
• Positive pregnant women should be treated to prevent neonatal disease
• Penicillin G is the drug of choice, but at 10x the MIC of S. pyogenes
• Aminoglycosides like streptomycin, gentamicin, or tobramycin can be added if the infection is severe
• Vancomycin is an alternative to Pen G if there’s a penicillin allergy
• S. agalactiae can cause bacteremia, pneumonia, and meningitis in neonates

Streptococcus Pneumoniae

• Streptococcus pneumoniae is a common inhabitant of the throat and nasopharynx in healthy people
• S. pneumoniae can move and spread to lungs to cause pneumonia, sinuses to cause sinusitis, ears to cause otitis media, CNS to cause meningitis or blood to cause bacteremia which often comes from pneumonia and memingitis
• S. pneumoniae pneumonia cases are around 500,000 per year in the US
• Sinusitis and otitis media affect about 7 million people each year in the US, and are considered to be ear infections
• Highest pneumonia incidence is in children and the elderly due to low antibody response to pneumococcal capsule polysaccharides
• Pneumonia often follows influenza or occurs in patients with COPD, congestive heart failure, diabetes, or renal disease
• Pneumonia vaccines exist for adults and children.
  • Adults: Composed of 23 capsular polysaccharides (PPSV23)
  • Children: Composed of 13 capsular polysaccharides conjugated to a protein(PCV13, 23 polysaccharides in the capsule
• Effective Antibiotics include Beta-lactams and erythromycin however penicillin resistance is a growing problem

Streptococcus Anginosus

• Streptococcus anginosus is a prevalent pathogen in endodontic abscesses, which are generally polymicrobial
• Endodontal abscesses can lead to bacteremia via vessels near teeth
• The situation is very Serious, and lead to shock and death.
• Treatment must be aggressive and diligent
• Pay close attention to a patient that deals with jaw pain and endodontic problems
• You can die from a toothache !!

Learning Objectives- Staphylococcus Vs Streptococcus

• Differentiate the general characteristics of aerobic/facultative, gram-positive cocci
• Discuss the two characterization approaches for Staphylococcus
• Describe the diseases, prevention, and treatment of S. aureus and S. epidermidis
• Discuss the three classification schemes for Streptococcus
• Contrast the diseases, transmission, prevention, and treatment of S. pyogenes, S. agalactiae, S. pneumoniae and S. anginosus

Learning Objectives - Bacillus Vs Clostridium

• Gram-Positive bacteria form endospores
• Differentiate facultative microbes from obligate microbes.
• Describe the diseases, transmission, prevention, and treatment of
  • B. anthracis
  • B. cereus
  • C. perfringens
  • C. tetani
  • C. botulinum
• Describe medical circumstances when botulism toxin would be used
• Describe Bacillus and Clostridium as Gram-positive endospore forming rods, Bacillus as an aerobe or facultative, and Clostridium as an obligate anaerobe.
• Describe the diseases, their transmission, prevention and appropriate examples of treatment associated with: -Bacillus (anthracis and cereus). -Clostridium (perfringens, tetani, botulinum, and difficile).
• Describe medical applications where botulism toxin is helpful (e.g.treatment of blepharospasm and wrinkles).

Bacillus Vs Clostridium

• both are Gram-positive rods with the only medically relevant endospore-forming genera
• Aerobic or facultative microbes undergo respiration or fermentation
• Anaerobic organisms are obligate anaerobes
• Bacillus and Geobacillus cannot survive in the presence of oxygen
• Clostridium undergoes only fermentation
• Clostridium cannot survive in presence of oxygen

Bacillus Anthracis

• Bacillus anthracis causes anthrax
• carries 2 important virulence plasminds that resist phagocytosis
• One plasmid codes poly-D-glutamate capsules, which resists phagocytosis so lasts longer in the body
• The other codes for 3 exotoxins: protective antigen, edema factor, and lethal factor which cause TNFα release

Bacillus Anthracis Edema and Lethal Toxins

• loses of plasmids loses virulence
• fluid accumulation is Edema toxin causes fluid accumulation in disease and is composed of a protective antigen and edema factor -an adenylate cyclase coverts ATP to cyclic AMP
• Lethal toxin is composed of protective antigen plus lethal factor (a zinc metalloprotease) and causes TNF-α release
• if Plasmids are lost, strain becomes avirulent
• Mainly a disease of ruminants (cattle, sheep, goats) & horses, but potentially found all around globe

Factors of Transmission and Risk

• People are infected by direct animal contact with trauma, trauma introduced soil contaminated with spores from animals, or inhalation of spores from dry animal hides or wool
• Groups at risk include veterinarians, cowboys, herders, and those taking part in who process animal hides and wool
• Those at risk include Soldiers and citizens, due to biological warfare
• Disease can happen from inhalation of spores from a letter.

Anthrax Types

• Can be cutaneous (most common type) that results from trauma from spores in animal or soil
  • Black eschar; redness remains
• A rare, but deadly form, can be pulmonary (aka Wool Sorter’s Disease) that results from the inhalation of spores from a number of sources. It is NOT spread person-to-person
• In a very rare event, one can contract gastrointestinal anthrax from consuming contaminated meat

Anthrax Treatment

• Cutaneous form is usually treated. If untreated, 20% mortality; mortality is < 1% if treated if mortality is <1%
• The Pulmonary mortality form has a 100% of those untreated will perish ; treated, 50 to 90% mortality
• Treatment requires (assuming not engineered to be resistant)Ciprofloxacin or Tetracycline or doxycycline or Penicillin G or Amoxicillin
• Cutaneous needs one method, pumonary needs multiple
• People exposed should get prophylaxis treatments

Bacillus Cereus

• Bacillus cereus food poisoning cases result due to growth of Bacillus cereus spores after cooking during storage, when food is stored for long periods of time
• The heat stable enterotoxin causes nausea, vomiting, and cramps
• The heat labile enterotoxin causes diarrhea
• There are cases it could be the other way around
• Ocular infections happens when this is introduced by penetrating trauma

Relevant Gram Positive Spore Formers

• Geobacillus stearothermophilus that requires autoclaves
• Formerly called Bacillus Stearothermophilus: a thermophile cannot cause humans
• Its spores in kit are used to test the autoclave function

Clostridium Perfringes

• Clostridium perfringens is an obligate anaerobe, toxic byproduct of fermentation, thats often found as gas gangrene
• Spreads broadly in soil, and resides heavily in feces
• The most serious issue is trauma or surgical wounds causing trauma
• Cellulitis and Fasciitis can occur, with bacteria species that are polymicrobial involved
• There can Myonecrosis which can leads to massive tissue and possibly death
• Puncture or deep wounds (penetrating trauma) are high risk which causes loss of air to the site since tissue is infected

Clostridium Perfringes Blunt Trauma

• Some blunt trauma wounds (e.g. crushing), causing little wounding on the surface, can cause necrosis, with infection via the blood stream, and still result in gas gangrene Agricultural injuries are a major source of trauma, and surgery leading to cause if gas gangerene

Clostridium Perfringes Food Poisioning and Treatment

• There are problems occasionally with Perfringens food poisoning due to enterotoxin in what you eat
• This comes from eating contaminated meat from not cooking fully, or being in an unrefrigrated container with no reheating that results into a toxin
• It takes 8 to 24 hours after eating these to get the symptoms with watery camp and then the rest Good wound cleaning and prophylactic penicillin
• Srehydrate with soup and water and it will resolve itself
• Avoid trauma and get good wound cleaning and prophylactic penicillin and surgery debridement
• Cook food well with appropriate refridgeration

Clostridium Tetani

• Clostridium tetani is ubiquitous in soil along with the GI tract of what humans and animals eat
• it grows locally as a result of tetanus being moved to puncture the wound
• tetano causes uncontrollable muscle contraction because nerve cells are damageed
• Tetanus is an issue 50 cases years in the us and 1 million each year

Clostridium Tetani Part II

• Tetanus toxin (tetanospasmin) is released by old cells within this area of growth where it blocks the release of neurotransmitters which irreversibly binds to site within nerve cells and stops the nerve cell
• Drooling and Lockjaw are the first symtpoms, followed by back spasms
• Cardiovascular and dehydrations begin to happen that have 20/50 percent death rate
• Anerobic Prevention- Vaccination is one way to ward off, so is cleaning the wound or using anetiseptic
• Treatment begins Metronidazole cannot work in presence of 02 with wound debridement and cleaning, and Tetanus antitoxin (passive immunity is another

###Clostridium Botulinum

• Clostridium botulinum is in Soil, & water
• Binding is irreversible, that nerve cell is finished, meaning recovery requires nerve cell regrowth
• Foodborne botulism, Infant botulism, and Wound botulism are the 3 diseases

FoodBorne Botulism and Its Treatment

• Improperly canned food, or not cooking food well leads to germination of spores, toxin production, and the symptoms as a result of intoxication
• Dizziness, weakness, blurred vision, dilated pupils, and flaccid paralysis are symptoms
• To prevent, eat canned food properly and cook it fully before eating.
• If toxins exist, they are heat stable
• to treat, you need ventilatory support and to eliminate the organism -gastric lavage -Metronidazole or penicillin -Antitoxin
• because there is only small ammounts of it's toxin normally significant in adults, it is more in infants

Clostridium Botulinum In Infants

• AKA Infant Botulism can result from feeding honey, therefore avoid feeding baby honey -The toxin is made in Gl tract and is called "Baby bot" or "floppy baby syndrome" (C. botulinum does not grow in adult intestine, but does in baby intestine)
• Symptoms are Constipation or Failure to thrive and they begin to have a Weak cry
• A child will Flaccid paralysis and act as a (floppy baby)
• It responds to just avoiding feeding honey and treating the symptoms
• The strains are floucid with postural abilities

Wound Botulism

• Can be prevented in foodborne through cooking and by not feeding infants honey
• To prevent, you can clean and debride
• It is treated as all Botulism illnesses do Botox -used to treat of eye twitch -Cannot keep eyes shut
  • Can result in death

Clostridium Difficile

• Part of intended flora as part of a population of 1 to 3 percent
• The transmission is transmitted in hospital where it is "hospital acquired"
• This is normally no problem but you can treat pts as needed with certain antibiotics
• You can give Probiotics pts that deal with antibiotics -Overgrowths C. difficile, there are great amounts of entertoxin and cytotoxin Cuses dirrera mild to serve CD AD
• Give probiotics to prevent after antibiotics

Clostridium Difficile II Rifaximin and Treatment

• stop antibiotics in this instance

• rehydrate, use rehydrate, use proboitics and you need to find a new antibiotic

• Treat with vancomycin or fidaxomicin (Dificid) but older methods use metronidazole

• if money is limiting)

• New options are rifaximin but betters tolerance

• Fidaxomicin acts an unusual macrocyclic antibiotic -It has the power to affect RNA which has an expensive

• Vanconomycyin also has a Large structure its use is limited in the GI tract.

• Also, poorly absorbed

• It is expansive -Clostridium Difficile Overview

• 12 of HAI are 100,00 thousand cases in the units

• 17 percent death rate a year

• even that one treatment that is newer as in and it carries at at major medical centers has fecal from a person with "healthy balance" A newer, "the idea of using Clostridium scindens Biosupplementation" inhibit C. difficile (still in development)

Learning Obectives

• Aerobic/Facultative Microbes, Gram. += cocci
• two classification:
• Staphylococcu
• Streptococcus
• Diseases -S Aureus and Epidermidis
• Prevention and Treatment
• Three classification Schemes Diseases-
• s pneumonia
• s pyogenes
• s Agaloatiae
• s anginosus Treatment, transmission, prevention

General Characteristics; Gram-negative Outer Membrane

• Name the most common genera of enterics and describe their importance in septicemia, urinary tract infections, and diarrheal infections. -bacteremia -This is all because of gram negative rods which are faculative, which have an outer membrane
  • Escheraia Describe the architecture of the cell wall and outer membrane of E. coli. Describe the causative agent, route of infection, symptoms, and where appropriate some description of treatment options for typhoid fever, paratyphoid fever, salmonellosis, shigellosis, Yersinia gastroenteritis, and the bubonic plague.

Enterics

• hot part of common are flora accident