BUGS DRUGS II Flashcards
Pseudomonas Stain ect S/S Transmission Dx Tx;
Gram negative rod, oxidase positive, catalase positive, encapsulated, obligate aerobe, non-lactose fermenter
Grows a blue-green pigment and smells of grapes (disgusting)
Weakly invasive but RESISTANT. Infects sick, immunocompromised hospitalized pts. IF HEALTHY, no problem.
Toxin: Exotoxin A (similar diptheria toxin)
Clinical Manifestations: #Pneumonia (especially CF patients) #Osteomyelitis #Burn victims #Sepsis #UTI #Endocarditis #External otitis #corneal infection
BE PSEUDO Burns Endocarditis (R heart valve IV users) Pneumonia Sepsis External malignant otitis UTI Diabetic osteomyelitis \+Hot tub folliculitis
Tx; aminoglycoside + extended spectrum pcn (piperacillin/ticarcillin)
Staghorn calculus in kidney?
Proteus (Urease positive)
Cause of Laryngeal papilloma?
HPV 6 /11 It may (rarely) progress to laryngeal carcinoma
Most common cause of laryngotracheobronchitis?
LTB is also called croup
-parainfluenze is most common cause
Most common cause acute epiglottitis
H. Influenze type B
Most common cause Rhinosinusitis?
Most common bacteria?
Viral URI; Rhinovirus most common cause rhinitis
Bacteria: H flu, S. pneumo, Moraxella
Most common cause atypical pneumonia?
Clinical manifestations
Complication?
Tx?
Mycoplasma pneumoniae. Slow growing, no cell wall. Membrane contains sterols. Mycoplasmas do not synthesize amino acids, metabolize lipids, or synthesize cholesterol.
“Walking pneumonia” (most common atyp pneumonia)
S/S insidious onset, headache, nonproductive cough, diffuse interstitial infiltrate (X-RAY looks worse than patient presents), fever, malaise, myalgia. Constitutional symptoms often predominate over respiratory symptoms.
complication: cold hemolytic anemia (IgM) and erythema multiforme, SJS/TEN
Tx; macrolides or Tetracycline, or flouroquinolones (PCN ineffective as no cell wall)
Acyclovir and Ganciclovir
What action?
Difference?
Both are guanine analogues
Acyclovir activated by viral thymidine kinase for HSV 1,2 and VZV
Ganciclovir is not viral enzyme dependent, used for EBV, CMV and ALL Herpes Viruses. Toxic to rapdily dividing cells in human, esp neutrophils and platelets
Foscarnet
MOA
Use
SE
Pyrophosphate analogue that inhibits DNA polymerase and reverse transcriptase
USE: #CMV retinitis #Acyclovir resistant herpes
SE: Nephrotoxicity
Most common cause
typical CAP
#1 Pneumococcus #2 H. Flu
Pneumoccal pneumonia
acute, local, alveolar, sputum
H. Flu pneumonia
cough, purulent sputum, fever, NO cxr infiltrate
pneumonia epidemiology children
Pneumonia kills more children than HIV, malaria, measles combined
1/5 deaths under 5 worldwide
Influenza A pneumonia
S/S
Season;
Dx;
Tx;
Prevention
S/S: cough/fever, usually mild-> hosp -> ICU
Season: Dec - April
Dx; PCR (rapid test not that sensitive)
Tx; Oseltamavir
Prevention: Influenze vaccine
Efficacy 6mo - 7yr = 83%
18-64 = 59%
- *Also superimposed bacterial infection: pneumococcus, S. Aureus, Group A strep
- ** Also other viral infections occur
Oseltamavir
MOA
jhkjh
Measles attack rate
> 99%
Most common atypical pneumonia?
Mycoplasma Pneumoniae
Legionella Stain ect Clinical manifestations Transmission Dx Tx;
Faculatative anaerobe (lives in macrophages and prevents phagosome/lysosome fusion)
Gram negative rod, stains poorly, use SILVER stain
Grow on charcoal yeast with iron and cysteine
Pontiac fever: mild, self limited flu-like illness
OR
Legionnaires disease
S/S Pneumonia (INTERSTITIAL) with fever, malaise, coughing, chills, diarrhea.
Transmission: aerosol from water source (no person-person)
Dx; antigen in urine, hyponatremia
Tx; macrolide or quinolone
*legionnaire with silver helmet, campfire, iron dagger, no sissy
Mycobacteria Tb
LAB
Epidemiology
Transmission:
Clinical manifestations
Initial infection: asymptomatic/mild flu-like, ghon complex formation (subpleural/interfissure granuloma) with hilar involvement
Strictly aerobic rod-shaped slow growing, acid-fast (resists destain by acid). 6-8month survivability exposed to env. Facultative intracellular. Lives intracelllularly in macrophages (prevents phagosome maturation).
Don’t have an outer membrane, but instead unipolar lipids that make up 60% of cell wall. Most of these are mycolic acids…
Epidemiology: 1/3 world infected, 1.5million deaths/yr
Transmission: Droplets (cough, sneeze, spittle talk)
Clinical: Can be pulm, disseminated, or both
–> 5-10% progress in 2yrs to ACTIVE primary Tb: progressive lung disease, pleural effusion, miliary tb, hematogenous spread
Reactivation (2ndary):
#Systemic: fevers, chills, night sweats, weight loss, fatigue
-Meningitis (base of brain)
-Lumbar Vertebrae (pott disease)
-Kidney (sterile pyuria)
-cervical lymph nodes
#Apex of lung reactivation: Simon focus (high Oxygen tension)
Dx; X-ray, also PPD (Tuberculin protein)
Which mycobacterium has not been cultured?
Mycobacterium leprae
Mycobacterium tuberculosis macrophage survival
Man-LAM: Inhibit phagosome maturation
Sulfatides #PIM: fusion phagosome -> early endosome = nutrients
1st line therapy Tb
Isoniazid (INH): Inhibits mycolic acid cell-wall synthesis
Rifampin (RIF): Inhibits RNA synthesis by binding beta subunit DNA dependent RNA polymerase; turns body fluids red-orange (which is effective in determining patient compliance); bactericidal;
Pyrazinamide (PZA): Derivative of nicotinic acid, target unknown, requires acidic pH for activity, and is highly specific for M. tuberculosis; slowly bactericidal;
Ethambutol (ETH): Inhibits arabinogalactan cell wall synthesis and is specific for mycobacteria; bacteriostatic;
You’ll RIP if you aren’t RIPE, 6-9 months
RI for 6-9 mo, PE stopped after 2
Rifampin turns fluid red-orange
TB resistance
OCcurs by chromosome mutation, NOT from viruses.
MDR: >= INH&RIF
TB vaccine
BCG, may create positive skin test
- little to no efficacy in primary pulm tb
- may help with meningeal/disseminated tb, esp in children
Klebsiella
Gram negative rod, encapsulated, catalase positive, oxidase negative, lactose fermenter
Normal enteric flora
Cause of lobar pneumonia alcoholics/diabetics on aspiration. Very mucoidal (polysacharide capsule) -> red currant jelly sputum.
Common nosocomial UTI cause
4A’s: Aspiration pneumonia, abscess in lungs/liver, alcoholics, diAbetics
Orthomyxoviridae Virology Epidemiology (incidence) Transmission Clinical manifestations Tx;
Virology: 8 segment, RNA (-) bound by nucleoprotein (NP)
- internal M protein
- lipid bilayer
- Hemagglutinin (HA)
- Neuroaminidase (NA)
- 3 types: A (mammals/birds), B/C human only
Epidemiology: #20% world infected/yr
Transmission: aerosolized. H5N1 avian flu (50% mortality) has yet to be pandemic bc not aerozolized (yet).
Clinical manifestations:
#”Flu” - 1-2 day incubation, abrupt onset, resolves 3-7days
- Fever, chills, malaise, myalgia, headache + dry cough, sore throat, rhinorrhea
-
#Primary pneumonia #predispose secondary pneumonia (S. Aureus, H. Flu, Pneumococcus)
Tx; oseltamavir or zanamivir (mimic sialic acid receptor substrate of NA), prevent virus from escaping infected cell.Effective prophylactic and reduces severity and duration of disease by 1-2 days.
Amantanes: currently not used due to resistance. Block acidification of interior virion through M2 ion channel inhibitor –> virus cannot uncoat.
Orthomyxoviridae hemagglutinin and neuraminidase
- MOA
- Antigenic Shift vs drift
- Anti-virals
HA: binds sialic acid receptors of erythrocytes and upper respiratory tract cells -> membrane fusion and hemagglutination
Antigenic drift are small mutations (like point) that alter antigenic determinants and make the virus infective again (but often to lesser degree in prior immunized hosts). These are the causes of EPIDEMICS
Antiginic shift is denoted by #’s, e.g. H1N1 vs H2N3… They only occur in Flu A strains, as they are a result of coinfection of strains in animal reservoirs. Swine are common reservoirs for avian and human mixing. These are the causes of PANDEMICS.
What viruses associated with Reye’s syndrome?
Influenza and varicella
Rubella
rash (head -> torso -> extremities)
- mild febrile, flu-like illness
- Lasts 3 days
CONGENITAL DEFECTS!!! TORCHES
common anaerobic lung abscess bacteria
Normal oral flora aspirated
Bacteroides, fusobacterium, peptostreptococcus
Triggers of SJS/TEN
Drug
Infection
Drugs:
- Allopurinol (gout)
- sulfa (antibiotic)
- lamotrigine (anti-epileptic)
Infectin:
- Mycoplasma pneumoiae
- VMC
Top 3 resp infections <5y/o
1) RSV
2) Parainfluenza (croup)
3) Adenovirus (have live unattenuated vaccine for military recruits)
What two bacteria have sialic (N-acetyl neuraminic acid) capsules that are found in human cells?
Why improtant
N. Meningitidis group B capsule (not the other 9 serotypes)
and
E. Coli with it’s K1 capsule
**Cannot make vaccine because it’s the same structure many human cells have.
Name 3 notable bacteria with IgA protease
The SHiN’s!
S. pneumonia’
H. Flu
Neisseria meningitidis
3 bacteria with urease (cause struvite ammonium mag phosphate stones)
proteus, staph, klebisella