Main powerpoint bacteria, Emerg data, all screenings, some lab testing Flashcards
Staph aureus
most pathogenic
staph epidermidis
common on skin, hospital acquired infections
Staph. Saprophyticus
Urinary tract infections
Staph. lugdunesis
Foreign body/prothetic devices
Coagulase neg staph species
S. epidermidis, S. saprophyticus, S. lugdunensis
Coagulase pos staph species
S. aureus
in general where can you find staph
on skin and anterior nares of healthy adults, and they are waiting to strike
Staph exotoxin production
Staphylococcal food poisoning
Toxic Shock Syndrome
Scalded Skin Syndrome
Staph Direct Tissue Invasion -
Most Common
Skin and soft tissue infections
Osteomyelitis
Septic arthritis
Pneumonia
Endocarditis
Can staph lead to bacteremia?
yes
Osteomyelitis is caused by-
Staph 60% of the time
How does S aureus produce exotoxins on food if it lives on human skin?
Non-infective carriers can pass S. aureus on to food (buffae or food not cooked)
Food improperly cooked or left at room temp = allow bacteria to reproduce and produce toxin
Strep pyogenes infections and complications
Strep throat
Peritonsillar abscess
Scarlet feverImpetigo
Erysipelas
Cellulitis
Rheumatic fever
Acute glomerulonephritis
can occur up to 2 weeks after infection
What does scarlet fever have to do with strep?
GABHS producing exotoxin may cause scarlet fever in susceptible persons
Cellulitis- is caused by what?
GABHS or S aureus
What causes Erysipelas
S. aureus or GABHS
What causes impetigo
GABHS or S. aureus
What causes scalded skin?
S. aureus TOXINS
What kind of infection is Necrotizing facilitis?
GABHS, hard to distinguish from C. perfringes
What causes toxic shock syndrome?
S aureus is the one we study in class, but there’s also one for GABHS
What causes arthritis?
GABHS
Risk factors for OM
smoking in household
family history
bottle feeding
MC kids 2-14
Incomplete hemolytic (alpha hemolytic)
strep pneumoniae
Acute sinusitis MC and RI
viral
-Secondary bacterial infections:
S. pneumoniae
S. aureus
H. influenzae
M. catarrhalis
Risk Factors:
Allergic rhinitis
Structural abnormalities
Nasal polyps
MC of CAP
S. pneumoniae
Curb 65
determine if a person with pneumonia should get inpatient treatment:
Confusion (+1)
BUN 20+ (+1)
RR. 30+ (+1)
SBP less than 90, DBP 60 or less (+1)
Age 65 or more. (+1)
3+ points mean inpatient
2 points means consider inpatient or out w/ close f/u
1 point means outpatient treatment
PSI/PORT Score
PSI/PORT Score: Pneumonia Severity Index for CAP
Estimates mortality for adult patients with community-acquired pneumonia.
MUST HAVE LABWORK FOR THIS
Emerging Data
Doxycycline associated with reduced infection in C. Diff versus Azithromycin
Who gets the Pneumovax vaccine?
Pneumovax is for all adults 65 and older, anyone ages 2-64 with (DM, LungD,HD,cirrhosis, SC), immunocompromised, anyone 19-64 who smokes, has asthma, resident of a nursing home.
Who gets Prevnar?
All kids ages 2, 4, 6, 12-15 mo.
All adults 65+ who have never gotten Prevnar 13.
Do we need to know whats on the next slide?
MC Meningitis kids and YA
Group B strep
baby
S. pneumoniae
toddler to school age
Neisseria meningitidis
teenager
S. aureus (more common with penetrating head trauma)
H. influenzae (Rare in US after HIB vaccine, still seen outside US)
MC Meningitis Adults and Elderly
Adults
S. pneumoniae
S. aureus
N. meningitidis (less common here)
Elderly
S. pneumoniae
S. aureus
Listeria monocytogenes
MC meningitis immunocompromised
Pseudomonas, Listeria, and Gram -
Enterococcus species
E. faecalis
E. faecium
Enterococcus - problems? and tx
Endocarditis
ampicillin + gentamicin
Skin/wound/UTI infections
Mild - ampicillin or vancomycin
Complicated - ampicillin or
vancomycin
Resistance
VRE - Vancomycin Resistant -Enterococcus
Recommended treatment:
linezolid
daptomycin
characteristics of B. anthrax
Encapsulated, toxin producing bacteria
Naturally transmitted via contact with infected animals or their products.
Bioterrorism agent
CDC Tier 1
Toxins (spores) can be weaponized as a fine powder
Bacillus Cerus characteristics
Produces toxins, causes diarrhea and emesis
Listeria Monocytogenes characteristics*
Most infections in neonates, the elderly, and immunocompromised persons
Great risk during pregnancy
Spontaneous abortion
Neonatal meningitis
Transmitted via ingestion of contaminated foods
Dairy / Queso Fresco cheese
Raw vegetables
Meat
(presentation is bacteremia, meningitis, dermatitis, oculoglandular)
Prevention of Diphtheriae?
Active immunization with diphtheria toxoid is part of routine childhood immunizations with appropriate booster injections
Susceptible persons exposed to diphtheria should receive a booster dose ofdiphtheria toxoidas well as a course of PCN orerythromycin
(&treat contacts of infected with erythromycin)
Acinetobacter Infections
Opportunistic infections in hospitalized, critically ill and immunocompromised
Can affect any organ system
resp MC, infect tracheostomy sites, suppurative infections, bacteremia
Can survive on dry surfaces for up to a month
Moraxella Catarrhalis
Acute otitis media (AOM)
Acute and chronic sinusitis
COPD exacerbations
Neisseria Meningitidis -
Meningococcal Meningitis
Characteristics
Characteristics
Human reservoir
40% of adults are carriers
Spread via person to person
Outbreaks occur in close communities
Military camps
College Dorms
Schools and Daycare
Outbreaks more common in winter and spring b/c cooped up more
More common in children, adolescents, and young adults
Previous infection or vaccination confers immunity
Meningococcal (Neisseria) Prevention
Prevention
Meningococcal Vaccine (a vaccine that covers strains A,C,Y, and W, as well as a vaccine that covers strain B - CDC recommends vaccination of all children starting at age 11-12 with booster at 16
New Emerging Prevention
Penbraya - covers strains A,C,Y,W, and B
Approved by FDA
Gonorrhoeae Emerging data &chlamyidia
Evidence from this analysis supports the Centers for Disease Control and Prevention’s recommendation that vaginal swabs are the optimal sample type for women being tested for chlamydia, gonorrhea, and/or trichomoniasis (over urine)
FDA grants approval for first time to a home test for chlamydia and gonorrhea
Pseudomonas characteristics
Most common: Pseudomonas aeruginosa
Gram - rod
Primarily found in water and soil
Causes opportunistic infections
Healthy individuals
otitis externa, UTIs, dermatitis
Immunocompromised hosts, ex) burn patients; CF; VAP
UTIs, pneumonia, bacteremia, sepsis
Pseudomonas Aeruginosa MC
1 pathogen
Most common first symptom is a fever
Otitis externa
Corneal ulcers from bacterial keratitis in contact lens wearers
ICU-related pneumonia
Osteochondritis after puncture through tennis shoe
#2 pathogen
Gram - organism in nosocomial pneumonia
#3 pathogen
Hospital-acquired UTIs
Folliculitis
“hot-tub folliculitis”
urticarial plaques, papules/pustules
pruritus
7-10 day duration
Klebsiella infections
UTI and Pneumonia
HaemophilusInfluenzae
Sinusitis, OM, bronchitis, Epiglottitis, Pneumonia, Cellulitis, Meningitis, Endocarditis
H flu characteristics
Haemophilussp colonize the upper respiratory tract in patients with COPD and frequently cause purulent bronchitis.
Common cause of sinusitis, otitis, or respiratory tract infection.
Empiric antibiotic treatment depending on area of infection
Legionaires characteristics
More common in immunocompromised persons, smokers, and those with chronic lung disease
Klebsiella Pneumoniae characteristics
Normal intestinal flora
Typically, only causes disease in immunocompromised persons
Alcoholics
Diabetics
HIV
Klebsiella can also cause UTIs
What is travelers diarrhea caused by?
E. coli
(tenesmus, 4-5 loose watery stools, fever)
What is campylobacteriosis caused by?
Campylobacter Jejuni
Salmonella disease facts
Enteric fever - the best example of which is typhoid fever,Caused by Salmonella typhi / enterica
(Typhoid Fever). Serotypes other than typhi typically do not cause invasive disease.
10/10/10 Has a prodromal stage of the flu, sore throat, abd pain, and then worsens.. rose spots and bloody pea soup. 2% mortality. Elderly do poorly. Relapses 15% of cases.
Acute enterocolitis - caused by S.typhimurium and S.enteritidis, among others
Infection transmitted by consumption of contaminated food or drink. The incubation period is 5–14 days
Characteristics of salmonella enterocolitis - Caused by S.typhimurium and S.enteritidis, and others
Modes of transmission
Ingestion of infected foods
Eggs, poultry/chicken
Raw milk
Meat
Direct contact with infected animals
Pet turtles and reptiles
inflammatory diarrhea
UTI is caused by what
Most caused by Escherichiacoli (E coli). Also, Klebsiella, Proteus mirabilis, Enterobacter
Emerging Data yersinia pestis
its making a reoccurance in navajo, kenya, china, oregon, madagascar
Francisella tularensis characteristics
Caused by Francisella tularensis
History of contact with rabbits, rodents, and ticks in endemic areas
Spreads easily by aerosol;highly virulent
CDC category A
eschar on thumb
FUO characteristics
Fever >38.3 degrees C (101.9 degrees F) on several occasions taken with an oral thermometer
Failure to make diagnosis despite 1 week of inpatient investigation
> 3 weeks duration
FUO labs
Lab Studies
CBC with diff
Peripheral blood smear
CMP - along w/ Hepatitis A,B,C w/ any abnormal liver studies
ESR or SED rate
UA and Cx
Blood cultures - at least 3 sets from different sites drawn several hours apart
HIV serology
TB serology
CXR
SIRS Defintion
Defined as 2 or more of the following:
Fever >38C (100.4F) or less than 36C (96.8F)
Heart rate >90 bpm
Resp rate >20 bpm or arterial carbon dioxide tension (PaCO2)<32 mmHg
Abnormal WBC
>12,000 or
<4,000 or
>10% bands
Bacteremia
Bacteria in the bloodstream which may multiply and produce systemic signs and symptoms
>200,000 deaths / yr.
20-35% with severe sepsis / 40-60% septic shock die w/in 30 days
Respiratory infection most common cause
Highest among those patients ≥ 65 y/o
Incidence greatest in winter months with resp infection
Gram + bacteria most prevalent, with Gram - and fungal increasing
Sepsis Signs and Symptoms
Usually coincides with the infectious source
Example: cough with dyspnea = pneumonia
Hypotension
Systolic BP <90
Elevated temperature (>38 degrees Celsius) or hypothermia (<35-36 degrees Celsius)
Heart rate >90 bpm
Tachypnea, with respirations >20 breaths/min (producing resp alk with PaCO² <32)
Signs of end organ perfusion
Warm, flushed skin
↓ cap refill, cyanosis, mottling
Altered mental status
Absent bowel sounds
SOFA score
Identification of early sepsis via Sequential Organ Failure Assessment score (SOFA) – must act quick after 2 or more
A qSofa score of ≥2 is associated with poor outcomes due to sepsis:
Resp rate ≥22 / min
Altered mentation
Systolic BP ≤100 mmHg
If above meets criteria, do full SOFA score
Sepsis Lab findings
Leukocytosis (WBC >12,000) or leukopenia (<4,000)
Normal WBC with >10 immature forms
Hyperglycemia w/o diabetes
>140
C-reactive protein (CRP) >2 SD above normal
Arterial hypoxemia
Acute oliguria
<0.5 mL/kg/hr for at least 2 hours despite fluid resuscitation
Coagulation abnormalities
INR >1.5 or aPTT >60 sec
Thrombocytopenia
Platelets <100,000
Hyperbilirubinemia
Tot bili >4 mg/dL
Adrenal insufficiency
Hyponatremia
Hyperkalemia
Hyperlactatemia
Serum lactate >2 mmol/L
Plasma procalcitonin (PCT) >2 SD above normal
Specific to bacteria infection
Sepsis Prognosis
Nosocomial pathogens - higher mortality rate than community-acquired pathogens
Early administration of appropriate antibiotics = beneficial impact
UTI - lowest mortality
Ischemic bowel - highest mortality
Mortality 50-55% when source of infection unknown (which is why we do empiric abx)
Strep throat screening
Centor Criteria
History of Fever, Tonsillar exuhate, tender anterior cervical adenopathy, abscence of a cough = +1
14 and younger = +1
45 and up = -1
1 point = not at all
2-3 = cx. if pos, treat with abx
4+ = just give abx
don’t give to kids 3 yrs old and younger unless they are at risk (outbreak at a daycare, contact w strep +, clinical findings)
don’t do routine strep throat screening of asymptomatic people.
How long does it take for a throat culture?
24-48 hrs
When is sensitivity testing indicated?
pathogens unknown, suspected mixed pathogens
known resistance
severe infection
infection is not responding to 1st line
When does sensitivity testing results come in?
1 to 2 days after cx results.
Nitrites are produced in the urine by what
gram negative bacteria
Desired insertion point of lumbar puncture
L3-L4 or L4-L5
Path of LP
Supraspinous, Interspinous, Ligamentum Flavum “pop”, epidural space “pop”, dura mater, subarachnoid space
How many tubes do you collect for CSF analysis
4 total
Cell count and differential
Glucose and protein levels
Gram stain, C&S
other (lactic acid, LDH, CRP) - only order if other tests abnormal
pleural fluid analysis: Light’s criteria
Pleural effusion is exudative (*cloudy inflam from protein being high in the ECM) if ONE of these exists:
Pleural fluid protein: serum protein greater than 1:2
Pleural fluid LDF:serum LDH greater than 0.6
Pleural fluid LDH is greater than 0.6, or greater than 2/3 times the normal upper limit for serum LDH
What is LDH
Lactate Dehydrogenase
elevated in bacterial infections and leukemia
What is Lactic acid used to measure
elevated in bacterial or fungal infections
What is measured in pleural fluid analysis
Glucose, Lactate levels, amylase, TG (triglycerides), Tumor markers
high TG levels mean
lymphatic system involvement
Amylase in pleural fluid analysis measures what
increases with pancreatitis, esophageal rupture, or malignancy
Glucose goes down why
Infection. If down more, malignancy
Review pericardiocentesis in slides
Arthrocentesis - string like vicosity
normal
Arthrocentesis - increased viscosity
septic arthritis
Arthrocentesis - decreased viscosity
inflammation
Arthrocentesis - red rusty brown
fresh or old blood
Arthrocentesis - yellow/green
inflammatory, infectious
CT vs MRI
CT utilizes radiation to produce images quickly, bone detail good, contrast can be added IV, PO or PR
MRI uses magnetic fields and radio freq. pulses to produce a more detailed image of soft tissue. Req long time and contrast can be added PO or IV
How many culture CFU to be a positive urine culture
100,000 of a SINGLE bacteria
What can’t you grow on a sputum culture?
Atypical bacteria, mycobacterium (TB), and fungal infections. TB can be diagnosed with Acid Fast Testing and culture specific for TB. this requires 3 seperate sputum samples and 12 weeks for a definitive diagnosis. Fungal infections often require serum testing or biopsy.
MC on a heart prosthetic valve
Strep bovis (endocarditis)
MC on a heart native valve
Strep viridans (endocarditis)
Syphillus emerging data
The number of babies born with syphilis is surging
9/10 were preventable
Things I need to know about pneumonia tx
If they have comorbiditis, that includes smoking. If they had abx in the last three months, that counts. If that had COPD, that counts as well. That qualifies them for Levofloxacin or either IP or OP treatment.
Rocephin + Z pack
emerging data cap
If you do doxycycline for CAP it will lower risk of C diff versus zithromax
Emerging data whooping
Whooping cough is rising in some countries and boosters may be needed
Emerging topics Shigella
Extensively drug resistant shigelloisis is on the rise in the US
Vibrio Cholera Emerging Data
Multple cases of vibrio cholera recently
Emerging Data Vibrio Vulnifics
Missouri man dies after eating raw oysters from contracting this.
