Gram Negative Algorithm Flashcards
1
Q
Neisseria Meningitidis (gram - diplococci) (catalase and oxidase +)
A
- ferments glucose (and Maltose)
- IgA protease
- Polysaccharide capsule, vaccine (none for B)
- Respiratory and oral secretions
- Waterhouse-Friderichsen syndrome
5a. catalase and oxidase + - treat: Pen G, ceftriaxone
2
Q
Neisseria Gonococci (catalase and oxidase +)
A
- Sexually transmitted
- No polysaccharide capsule
- septic arthritis
- Fitz Hugh Curtis syndrome (adhesions to liver capsule)
- No maltose fermentation
- catalase and oxidase +
3
Q
Haemophilus Influenza
child with trouble breathing and swallowing, “sitting dog position”, and increased drooling–> comporamised airway (dont upset kid)
A
- Capsular Type B–most invasive disease
- IgA protease production
- MOPS
- Cherry red epiglottis in children
- Chocolate agar for growth (factors V-NAD and X-hemantin)
TX: amoxacillin + clavulanate acid
4
Q
Haemophilus Ducreyi
A
Chancroid, genital ulcer, solitary and painful. (unlike syphilis which is a painless chancre)
5
Q
Legionella Pneumophila
A
- cause of atypical pneumonia
- Silver stain
- grow on charcoal yeast extract (with iron and cysteine)
- Urine test (antigen in urine)
- Water source transmission (air conditions, hot water tanks)
- no person to person
6
Q
Pseudomonas Aeruginosa (lactose non fermenter, oxidase +)
A
- grape like odor
- pyocyanin (blue green pigment)
- Water source, Wound infections, BURNS
- Chronic Pneumonia in CF
- endotoxin, exotoxin A (inactivated EF-2)
- hot tub folliculitis, swimmer’s ear
- Ecthyma gangrenosum
- immunocompramised (AIDS)
7
Q
EColi virulence factors
A
- Fimbriae–cystitis and pyelonephritis (allows ascension of bacteria up urinary tract)
- K capsule– pneumonia and neonatal meningitis
- LPS endotoxin–septic shock
8
Q
EIEC
A
- invades intestinal mucosa
- intestinal necrosis and inflammation
- Dysentery (bloody)
9
Q
ETEC
A
- traveler’s diarrhea
- heat labile toxin-(high AC–high cAMP)
3 heat stable toxin-(high GC–high cGMP)
10
Q
EPEC
A
- adheres to apical surface of intestinal cells and flattens villi (decreases absorption)
- Children
11
Q
EHEC (O157:H7)
A
- Shiga like toxin (ADP ribosylating AB toxin-inactivates 60s subunit–removes adenine)
- Dysentery
- HUS (anemia, thrombocytopenia, renal failure)
- NO ferment of Sorbitol ( all other Ecoli do)
- No glucuronidase (other Ecoli do)
- Microthrombi formed–> schistiocytes, and thrombocytopeia (use up platelets)
12
Q
Klebsiella (lactose fermenter-fast)
A
- Aspiration Pneumonia (lobar type)
- Alcoholics, diabetics, ICU?
- Mucoid colonies– Red Currant Jelly
- Abscesses in lungs and liver
- Nosocomial UTI’s
13
Q
Salmonella (lactose non fermenter, oxidase -)
A
- flagella, hematogenous spread
- H2S
- monocytic intestinal response
- bloody diarrhea
- antibiotics–prolong fecal excretion
14
Q
Shigella (lactose non fermenter, oxiade -)
A
- No flagella
- No H2S
- PMN intestinal response
- bloody diarrhea
- Antibiotics–shorten fecal excretion
15
Q
Salmonella Typhi
A
- Typhoid fever
- Rose spots on the abdomen
- fever, headache, diarrhea
- Carrier state–remains in the gallbladder
16
Q
Campylobacter jejuni (oxidase +, comma shaped)
A
- Bloody diarrhea in children
- Grows in hot environment (42)
- poultry, meats, unpasteurized milk
- Guillen Barre (ascending paralysis)
- Reiter’s (reactive arthritis)
17
Q
Vibrio Cholera (comma shaped, (oxidase +, comma shaped)
A
- Grows in alkaline media
- Cholera toxin: increases cAMP (permanently activates Gs)
- Rice water diarrhea
18
Q
Yersina Enterocolita
A
- Pet feces, contaminated milk, pork
- Appendicidis like pain
- mesenteric adenitis
19
Q
H. Pylori (comma shaped, oxidase +, catalase +)
A
- Urease +
- gastritis, peptic ulcers
- intestinal type gastric carcinoma
- Triple therapy: PPI+clarithromycin+amoxacillin/metronidazole
20
Q
Leptospira (spirochete)
A
- water contaminated with animal urine
- jaundice, photophobia
- conjunctival suffusion (erythema no exudate)
- surfers in hawaii
- Weil Disease –liver and kidney dysfunction
21
Q
Borrelia Burgdorfi (Lyme Disease)
A
- Mass. (northeast US)
- Ixodes tick (natural reservoir is the mouse)
- Bull’s eye rash (erythema migrans)
- 3 stages
- later stages–> monoarthritis, migratory polyarthritis
- Bell’s palsy (often bilateral)
AV node block
Wright or Geimsa stain to visual on light microscopy
22
Q
Treponema Pallidum (syphilis)
A
- Painless chancre –primary syphilis
- dark field microscopy
- 2* syphilis–> maculopapular rash on palms and soles
condylmata lata - 3* syphilis–> Gummas (chronic granulomas), Aortitis (vasa vasorum destruction), Argyll Robertson pupil ( not reactive to light, but constricts on accomodation)
23
Q
Congenital Syphilis
A
Saber shins, saddle nose, deafness (CN VIII), Hutchinson teeth, mulberry molars,
Transfer is in 1st semester.
24
Q
Bordatella Pertussis
A
- Whooping Cough
2. Pertussis toxin – inhibit phagocyte ability . disable Gi, increases cAMP, impairs phagocytosis.
25
Rocky mountain Spotted fever (Rickettsia R.)
1. Rash (palms and soles) and then spreads to trunk
2. Classic triad: headache, rash, vasculitis
3. Intracellular
4. vector-tick, south atlantic states (North carolina)
26
Chlamydiae (unusual cell wall no muramic acid)
a. ABC--Blindness, chronic, africa
b. D-K-- PID, urethritis, ectopic pregnancy (scarring of fallopian tubes). Neonatal conjunctivitis
c. L1,L2,L3-- buboes.
1. intracellular (cannot make own ATP)
2. elementary body, reticulate body
3. Trachamotis--STD, PID, Reiter's, follicular conjunctivitis
4. Psittaci--Pneumonia, bird vector (parrots)
5. C. pneumonia--atypical pneumonia
6. Geimsa stain
27
Mycoplasma Pneumoniae (gram pos?)
1. No cell wall
| 2. atypical pneumonia
28
Mycoplasma Pneumoniae (gram pos?)
1. No cell wall
| 2. atypical pneumonia
