FA - Micro - Systems Flashcards
Normal dominant flora - nose?
S.epi - colonized by S.aureus.
Normal dominant flora - Skin?
S.epi
Normal dominant flora - oropharynx?
Viridans group strep
Normal dominant flora - dental plaque?
S.mutans
Normal dominant flora - colon?
B.fragilis>E.coli
Normal dominant flora - vagina?
Lactobacillus - colonized by E.coli and group B strep.
Normal flora - neonates by C-section?
Have NO FLORA but are rapidly colonized after birth.
Food poisoning - starts quickly/ends quickly?
- S.aureus
2. B.cereus
Food poisoning - B.cereus source?
Reheated rice.
Food poisoning - C.perfringens source?
Reheated meat dishes.
Food poisoning - E.coli O157:H7 source?
Undercooked meat.
Food poisoning - Salmonella source?
Poultry, meat, and eggs.
Food poisoning - S.aureus source?
- Meats
- Mayonnaise
- Custard
==> PREFORMED TOXIN.
Food poisoning - V.parahemolyticus and V.vulnificus source?
Contaminated SEAfood.
V.vulnificus besides food poisoning?
Wound infections from contact with contaminated water or shellfish.
Mention altogether the most important food poisoning bugs.
- B.cereus
- S.aureus
- C.botulinum
- C.perfringens
- E.coli O157:H7
- Salmonella
- V.parahemolyticus and V.vulnificus
Bugs causing bloody diarrhea?
- Campylobacter
- E.histolytica
- EHEC
- EIEC
- Salmonella
- Shigella
- Y.enterocolitica
Bloody diarrhea - Campylobacter?
- Comma- or S-shaped organism.
2. Growths at 42C.
Bloody diarrhea - E.histolytica?
- Protozoan
- Amebic dysentery
- Liver abscess
Bloody diarrhea - EHEC?
- O157:H7.
- Can cause HUS.
- Makes Shiga-like toxin.
Bloody diarrhea - EIEC?
Invades colonic mucosa.
Bloody diarrhea - Salmonella?
- Lactose(-)
- Flagellar motility
- Animal reseervoir
- Especially POULTRY/EGGS
Bloody diarrhea - Shigella?
- Lactose(-)
- Very low ID50
- Shiga toxin - Human reservoir only
- Bacillary dysentery
Bloody diarrhea - Y.enterocolitica?
- Day-care outbreaks
2. Pseudoappendicitis
Watery diarrhea bugs?
- C.difficile
- C.perfringens
- ETEC
- Protozoa
- V.cholerae
- Viruses
Watery diarrhea - C.difficile?
- Pseudomembranous colitis
- By antibiotics
- Occasionally bloody diarrhea
Watery diarrhea - C.perfringens?
Also causes GAS GANGRENE.
Watery diarrhea - ETEC?
- Traveler’s diarrhea
2. Heat-labile and heat-stable toxins
Watery diarrhea - Protozoa
- Giardia
2. Cryptosporidium (immunocompromised)
Watery diarrhea - V.cholerae?
- Comma-shaped organisms
- Rice-water diarrhea
- Often from INFECTED SEAfood
Watery diarrhea - Viruses?
- Rotavirus
- Norovirus
- Adenovirus
Common causes of pneumonia - neonates (<4wk)?
- Group B strep
2. E.coli
Common causes of pneumonia - children (4wk-18y)?
- Viruses - RSV
- Mycoplasma
- C.trachomatis (infants-3y)
- C.pneumoniae (school-aged children)
- S.pneumoniae
Common causes of pneumonia - adults (18-40yr)?
- Mycoplasma
- C.pneumoniae
- S.pneumoniae
- Viruses ==> Influenza.
Common causes of pneumonia - adults (40-65y)?
- S.pneumoniae
- H.influenza
- Anaerobes
- Viruses
- Mycoplasma
Common causes of pneumonia - Elderly?
- S.pneumoniae
- Influenza virus
- Anaerobes
- H.influenza
- Gram(-) rods
Common causes of pneumonia - Alcoholic/IVDA?
Alcoholics ==> Klebsiella + Anaerobes (eg Peptostreptococcus, Fusobacterium, Prevotella, Bacteroides).
IVDA ==> S.pneumo + S.aureus.
Common causes of pneumonia - Aspiration?
Anaerobes
Common causes of pneumonia - Atypical?
- Mycoplasma
- Legionella
- Chlamydia
Common causes of pneumonia - CF?
- Pseudomonas
- S.aureus
- S.pneumoniae
- B.cepacia.
Common causes of pneumonia - Immunocompromised?
- Staph
- Enteric gram(-) rods
- Fungi
- Viruses
- P.jiroveci (with HIV)
Common causes of pneumonia - Nosocomial?
- Staph
- Pseudomonas
- Other enteric gram(-) rods
Common causes of pneumonia - Postviral?
- S.pneumo
- H.influenza
- S.aureus
Common causes of meningitis - Newborn (0-6mo)?
- Group B strep
- E.coli
- Listeria
Common causes of meningitis - Children (6-6yr)?
- S.pneumoniae
- N.meningitis
- H.influenza type B
- Enteroviruses
Common causes of meningitis - 6-60y?
- S.pneumoniae
- N.meningitidis (#1 in teens)
- Enteroviruses
- HSV
Common causes of meningitis - 60+y?
- S.pneumoniae
- Gram(-) rods
- Listeria
Meningitis empirical treatment?
- Vancomycin
- Ceftriaxone
- Add ampicillin if Listeria is suspected.
Viral causes of meningitis?
- Enteroviruses (Coxsackie)
- HSV-2 (HSV-1=encephalitis)
- HIV
- West Nile virus ==> ALSO causes encephalitis.
- VZV
In HIV - causes of meningitis?
Cryptococcus spp.
CSF findings in meningitis - Bacterial?
- UP pressure
- UP PMNs
- UP protein
- DOWN sugar
CSF findings - Fungal/TB?
- UP pressure
- UP lymphocytes
- UP proteins
- DOWN sugar
CSF findings in meningitis - viral?
- Normal/UP pressure
- UP lymphocytes
- Normal/UP protein
- Normal sugar
Osteomyelitis - assume no other info is available?
S.aureus (MC overall)
Osteomyelitis - sexually active?
N.gonorrhoeae (rare) - septic arthritis more common.
Osteomyelitis - IVDA?
- P.aeruginosa
- Candida.
- S.aureus.
Osteomyelitis - sickle cell?
- Salmonella
2. S.aureus
Osteomyelitis - prosthetic joint replacement?
- S.aureus
2. S.epi
Osteomyelitis - vertebral involvement?
- S.aureus.
2. Myco TB (Pott).
Osteomyelitis - cat and dog bites?
P.multocida
Osteomyelitis - target group?
Children
Osteomyelitis - Radiograph or MRI?
MRI ==> Acute infection + Detailing anatomic involvement.
X-RAY ==> Useful in CHRONIC osteomyelitis.
Cystitis presents with?
- Dysuria
- Frequency
- Urgency
- Suprapubic pain
- WBCs (but NOT WBCs casts) in urine.
Cystitis - mechanism in MALES - infants, elderly?
- Congenital defects (Infants).
- Vesicoureteral reflux (Infants)
- Enlarged prostate (elderly)
Pyelonephritis symptoms?
- Fever
- Chills
- Flank pain
- Costovertebral angle
- Tenderness
- Hematuria
- WBC casts
UTI - how more common in women?
10X! - shorter urethras colonized by fecal flora.
UTI - Predisposing factors besides female?
- Obstruction
- Kidney surgery
- Catheterization
- GU malformation
- Diabetes
- Pregnancy