X - Gram-Negative Bacteria Flashcards
(189 cards)
1
Q
Gram (-) diplococci, encapsulated, ferments maltose and glucose, kidney bean-shaped, large polysaccharide capsule, oxidase (+) on chocolate agar
A
Neisseria meningitidis
2
Q
Neisseria meningitidis: Location
A
upper respiratory tract, humans - only natural host
3
Q
Neisseria meningitidis: Transmission
A
respiratory droplets, close quarters (military, dormitories, camps)
4
Q
Neisseria meningitidis: Virulence factors
A
antiphagocytic polysaccharide capsule, endotoxin (LPS), IgA protease, complement deficiencies in the late-acting complement components (C5-C9)
5
Q
Neisseria meningitidis: Diseases
A
meningitis, meningococcemia, Waterhouse-Friderichsen
6
Q
Most common cause of meningitis among children 2-18 y.o.
A
Neisseria meningitidis
7
Q
Fever, headache, stiff neck, increased level of PMNs in spinal fluid
A
Meningitis (Neisseria meningitidis)
8
Q
Dissemination of meningococci into the bloodstream, multiorgan disease, consumptive coagulopathy, petechial or purpuric rash (purpura fulminans)
A
Meningococcemia
9
Q
Most severe form of meningococcemia, high fever, shock, widespread purpura, disseminated intravascular coagulation, thrombocytopenia, adrenal insufficiency (bilateral hemorrhagic destruction of the adrenal glands)
A
Waterhouse-Friderichsen
10
Q
Neisseria meningitidis: Treatment
A
Penicillin G, Ceftriaxone
11
Q
Neisseria meningitidis: Prevention
A
capsular polysaccharide (A, C, Y, W-135) coupled to a carrier protein (diphtheria toxoid) to enhance immunogenicity, Rifampin chemoprophylaxis for close contacts
12
Q
Gram (-) diplococci, ferments glucose only, kidney bean-shaped, insignificant capsule, oxidase (+) on Thayer-Martin medium
A
Neisseria gonorrhoeae
13
Q
Neisseria gonorrhoeae: Location
A
genital tract
14
Q
Neisseria gonorrhoeae: Transmission
A
sexual contact, passage through the birth canal
15
Q
Neisseria gonorrhoeae: Virulence factors
A
pili, lipo-oligosaccharide (LOS), complement deficiencies in the late-acting complement components (C5-C9), usual co-infection with C. trachomatis
16
Q
Neisseria gonorrhoeae: Localized
A
ophthalmia neonatorum, gonococcal urethritis, pelvic inflammatory disease
17
Q
Neisseria gonorrhoeae: Disseminated
A
septic arthritis
18
Q
Purulent conjunctivitis in newborns
A
Ophthalmia Neonatorum
19
Q
Most common cause of urethritis
A
Neisseria gonorrhoeae
20
Q
Urethritis and epididymitis in men
A
Gonococcal Urethritis
21
Q
Most common cause of PID
A
Neisseria gonorrhoeae
22
Q
Complications of PID
A
sterility, ectopic pregnancy, chronic pelvic pain dyspareunia, Fitz-Hugh-Curtis
23
Q
Violin-string adhesions, complication of PID
A
Fitz-Hugh-Curtis
24
Q
Most common cause of septic arthritis in sexually active adults
A
Neisseria gonorrhoeae
25
Arthritis, tenosynovitis, pustules on the skin
Septic Arthritis (Neisseria gonorrhoeae)
26
Neisseria gonorrhoeae: Treatment
Ceftriaxone + Doxycycline (C. trachomatis co-infection)
27
Neisseria gonorrhoeae: Prevention
barrier contraception, treat sexual partner, erythromycin ointment or silver nitrate to prevent conjunctivitis
28
Cause culture (-) subacute bacterial endocarditis in patients with pre-existing heart disease
Eikenella corrodens, Kingella kingae
29
HACEK Organisms
Haemophilus aphrophilus, Actinobacillus actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens, Kingella kingae
30
Gram (-) coccobacillary rods, enriched chocolate agar, polyribitol phosphate capsule, requires factor X (hemin) and V (NAD) for growth, satellite phenomenon around S. aureus
Haemophilus influenza type B
31
Haemophilus influenza type B: Location
upper respiratory tract
32
Haemophilus influenza type B: Transmission
respiratory droplets
33
Haemophilus influenza type B: Pathogenesis
type b (polyribitol phosphate), IgA protease, children 6-12 mos. (decline in maternal IgG and immature immune system)
34
Sinusitis, otitis media, pneumonia, meningitis, epiglottitis, COPD exacerbations
Haemophilus influenza type B
35
Most common cause of epiglottitis, cherry red epiglottis, thumb sign
Haemophilus influenza type B
36
Most common cause of COPD exacerbations
Haemophilus influenza type B
37
Laryngotracheobronchitis (Croup): Etiology
Parainfluenza Virus 1 & 2
38
Laryngotracheobronchitis (Croup): Radiographic Sign
Steeple Sign
39
Laryngotracheobronchitis (Croup): Treatment
Racemic Epinephrine
40
Haemophilus influenza type B: Treatment
Ceftriaxone
41
Haemophilus influenza type B: Prevention
HiB vaccine containing te type b capsular polysaccharide conjugated to diphtheria toxoid (2-18 mos.)
42
Gram (-) rods, Bordet-Gengou/Regan-Lowe agar, whooping cough
Bordatella pertussis
43
Bordatella pertussis: Location
upper respiratory tract
44
Bordatella pertussis: Transmission
respiratory droplets
45
Bacterial Croup: Etiology
Bordatella pertussis
46
Bordatella pertussis Virulence Factors: Mediates attachment
Filamentus Hemagglutinin
47
Bordatella pertussis Virulence Factors: Causes ADP-ribosylation and lymphocytosis
Pertussis Toxin - inactivates Gi (turns off the "off button")
48
Bordatella pertussis Virulence Factors: Inhibits phagocytic activity
False Adenylate Cyclase
49
Bordatella pertussis Virulence Factors: Damages ciliated cells, causes whooping
Tracheal Cytotoxin
50
Paroxysmal pattern of hacking coughs, accompanied by production of copious amounts of mucus, cough ends with an inspiratory "whoop"
Pertussis (Tuspirina)
51
Pertussis: Incubation
7-10 days
52
Pertussis: Catarrhal Phase
1-2 weeks
53
Pertussis: Rhinorrhea, malaise, fever, sneezing, anorexia, best time for blood CS
Catarrhal Phase
54
Pertussis: Paroxysmal Phase
2-4 weeks
55
Pertussis: Repetitive cough with whoops, vomiting, leukocytosis
Paroxysmal Phase
56
Pertussis: Convalescent Phase
3-4 weeks
57
Pertussis: Diminished paroxysmal cough, development of secondary complications (pneumonia, seizures, encephalopathy)
Convalescent Phase
58
Bordatella pertussis: Treatment
Erythromycin
59
Bordatella pertussis: Prevention
acellular vaccine combination with diphtheria and tetanus toxoids (DTaP)
60
Gram (-) rods, poorly gram staining, silver stain, charcoal yeast agar (iron, cysteine), airconditioning, facultative intracellular bacteria, rapid urinary antigen test
Legionella pneumophila
61
Facultative Intracellular Bacteria
Salmonella, Brucella, Mycobacterium, Listeria, Francisella, Legionella, Yersinia
62
Legionella pneumophila: Location
environmental water sources
63
Legionella pneumophila: Transmission
aerosol from water source (no human-to-human transmission)
64
Legionella pneumophila: Sole virulence factor
Endotoxin
65
Replicates intracellularly, eliminated by cell-mediated immunity, inhibits lysosomal fusion
Legionella pneumophila
66
Legionella pneumophila: Risk Factors
old age, smoking, high alcohol intake, immunosuppression
67
Pneumonia, confusion, non-bloody diarrhea, hyponatremia, proteinuria, hematuria
Atypical Pneumonia (Legionella pneumophila)
68
Mild, flu-like illness caused by Legionella pneumophila
Pontiac Fever
69
Legionella pneumophila: Treatment
Azithromycin, Erythromycin
70
Legionella pneumophila: Prevention
reduce cigarette and alcohol consumption, eliminate aerosols from water sources, high temperatures and hyperchlorination of hospital water supply
71
Facultative gram (-) rods, lactose fermenter on EMB or MacConkey's agar, green sheen on EMB agar (metallic sheen), acid slant and acid butt on TSI without H2S, typing by O and H antigens
Escherichia coli
72
Lactose fermenters
Citrobacter, Klebsiella, Escherichia coli, Enterobacter
73
Escherichia coli: Location
colon, vagina, urethra
74
Escherichia coli: Transmission
ascending UTI, neonatal meningitis, fecal-oral
75
Escherichia coli: Virulence Factors
pili, flagellum (H), capsule (K), endotoxin (O), enterotoxins - HST & HLT (watery diarrhea), verotoxin (Shiga-like) bloody diarrhea in HUS
76
Enterobacteriaceae
Morganella, Escherichia, Shigella, Salmonella, Yersinia, Serratia, Proteus, Enterobacter, Citrobacter, Klebsiella
77
Enterobacteria: Features
capsular antigen (K), O antigen, flagellar antigen (H), ferments glucose
78
Most common cause of community acquired UTI
Escherichia coli
79
2nd most common cause of neonatal meningitis worldwide, most common cause in the Philippines
Escherichia coli
80
Causes of Neonatal Meningitis
B group Streptococci (S. agalactiae), Escherichia coli, Listeria monocytogenes
81
Escherichia coli: Watery diarrhea, traveller's diarrhea, Montezuma's Revenge, Delhi Belly
Enterotoxigenic (ETEC)
82
Escherichia coli: Watery diarrhea of long duration, mostly infants (Pedia), often in developing countries (Philippines)
Enteropathogenic (EPEC)
83
Escherichia coli: Bloody diarrhea, hemorrhagic colitis, hemolytic uremic syndrome (HUS)
Enterohemorrhagic (EHEC), O157:H7
84
Escherichia coli: Bloody diarrhea, utilize adhesin proteins to bind to and enter intestinal cells
Enteroinvasive (EIEC)
85
Escherichia coli: Persistent watery diarrhea in children, HIV patients (AIDS)
Enteroadherent (EAEC)
86
Escherichia coli: Treatment
Ampicillin or Sulfonamides for UTI (Quinolones in the Philippines), 3rd gen. Cephalosporins for meningitis and sepsis, rehydration for Traveller's Diarrhea
87
Escherichia coli: Prevention
limiting urinary catheterization, switching IV lines promptly, boiling water
88
Non-lactose fermenting facultative gram (-) rods, motile, oxidase (-), H2S producer, Widal test detects antibodies, XLD medium (xylose-lysine-deoxycholate agar)
Salmonella
89
Salmonella: Location
colon (S. typhi), enteric tract of humans and animals (S. enteritidis)
90
Salmonella: Transmission
fecal-oral
91
Salmonella: Enterocolitis
S. enteritidis/S. typhimurium
92
Salmonella: Typhoid Fever
S. typhi
93
Salmonella: Septicemia
S. choleraesuis
94
Invasion of the epithelial and subepithelial tissue of SI and LI, high infectious dose, gastrectomy and antacids lower infectious dose
Enterocolitis (S. enteritidis/S. typhimurium)
95
Due to Vi capsular antigen, organisms enter, multiply in Peyer's patches, spread to reticulo-endothelial system, predilection for invasion of the gallbladder (chronic carrier state)
Typhoid Fever (S. typhi)
96
Bacteremia results in the seeding of many organs, osteomyelitis, pneumonia, meningitis, sickle cell anemia
Septicemia (S. choleraesuis)
97
Salmonella Enterocolitis: Incubation Period
12-48 hours
98
Typhoid Fever: Incubation Period
5-21 days
99
Salmonella: Nausea, vomiting, abdominal pain, non-bloody diarrhea
Enterocolitis
100
Salmonella: Fever, little or no enterocolitis, focal symptoms (bone, lungs, meninges)
Septicemia
101
Typhoid Fever Findings: Week 1
stepwise fever, anorexia, malaise, relative bradycardia, bacteremia
102
Typhoid Fever Findings: Week 2
abdominal pain, bloating, constipation, rose spots (salmon papules), hepatosplenomegaly, jaundice
103
Typhoid Fever Findings: Week 3
bleeding, ileitis, pneumonia
104
Typhoid Fever Findings: Week 4
recovery or death
105
Typhoid Fever Culture: Week 1
blood, bone marrow
106
Typhoid Fever Culture: Week 2
urine, rose spots, bone marrow
107
Typhoid Fever Culture: Week 3
stool, bone marrow
108
Typhoid Fever Culture: Week 4
bone marrow
109
Typhoid Fever Culture: Chronic Carrier
bile, stool, bone marrow
110
Salmonella: Treatment
Ceftriaxone, Ciprofloxacin
111
Salmonella: Treatment in the Philippines
Amoxicillin, Chloramphenicol, Cotrimoxazole
112
Salmonella: Treatment for Gallbladder Infection
Ampicillin - enterohepatic recycling
113
Salmonella: Prevention
public health measures - sewage disposal, chlorination, hand washing, food safety, S. typhi vaccine
114
Non-lactose fermenting gram (-) rods, non-motile, oxidase (-), H2S non-producer, O antigen, XLD medium (xylose-lysine-deoxycholate agar)
Shigella
115
Shigella: Location
colon
116
Shigella: Transmission
food, fingers, feces, flies
117
Invades the distal ileum and colon, low infectious dose (highly infectious), locally accompanied by ulceration, enterotoxin (Shiga toxin)
Shigella
118
Most common cause of bacillary dysentery
Shigella sonnei (Duval's bacillus)
119
Most severe form of bacillary dysentery, most common cause of epidemic dysentery
Shigella dysenteriae Type 1 (Shiga bacillus)
120
Group A - Shigella dysenteriae Type 1
Shiga bacillus
121
Group A - Shigella dysenteriae Type 2
Schmitz bacillus
122
Group B - Shigella flexneri
Flexner's / Hiss and Russell's bacillus
123
Group C - Shigella boydii
Newcastle Manchester bacillus
124
Group D - Shigella sonnei
Duval's bacillus
125
Incubation period of 1-4 days, fever, abdominal cramps, diarrhea (watery to bloody) resolving in 2-3 days
Bacillary Dysentery
126
Shigella: Treatment
fluid and electrolyte replacement, Ciprofloxacin for severe cases
127
Shigella: Prevention
public health measures - sewage disposal, chlorination, hand washing, food safety
128
Gram (-) rods, comma-shaped, motile, oxidase (+), shooting star, marine organism, thisulfate citrate bile salts sucrose (TCBS) agar, high infectious dose
Vibrio
129
Vibrio: Location
colon (V. cholerae), saltwater (V. parahemolyticus, V. vulnificus)
130
Vibrio: Transmission
fecal-oral (V. cholerae), contaminated raw seafood (V. parahemolyticus), trauma to skin, shellfish handlers, ingestion of raw shellfish (V. vulnificus)
131
Vibrio Virulence Factors: Acts by ADP-ribosylation
Enterotoxin (Choleragen) - activates Gs (turns on the "on button")
132
Vibrio Virulence Factors: Enhances attachment to the intestinal mucosa
Mucinase
133
Vibrio: Pandemics
Vibrio cholerae O1 biotype El Tor (Cholera El Tor)
134
Watery diarrhea in large volumes (rice-water stools), cardiac and renal failure, non-gap acidosis, hypokalemia
Cholera (V. cholerae)
135
Self-limited with an explosive onset of watery diarrhea, nausea, vomiting, abdominal cramps, headache, low-grade fever
Gastroenteritis (V. parahemolyticus, V. vulnificus)
136
Wound infections associated with exposure to contaminated water
V. parahemolyticus, V. vulnificus
137
Vibrio: Treatment
cholera - fluid and electrolyte replacement, Tetracycline/Azithromycin shortens duration, V. parahemolyticus/V. vulnificus - Minocycline + Fluoroquinolone/Cefotaxime
138
Vibrio: Prevention
public health sanitation, cholera vaccine - short-term immunity, herd immunity
139
Gram (-) rods, comma-shaped, microaerophilic, Skirrow's agar (42°C), Campy medium (antibiotics)
Campylobacter jejuni
140
Campylobacter jejuni: Location
human and animal feces
141
Campylobacter jejuni: Transmission
fecal-oral
142
Most common cause of bacterial gastroenteritis
Campylobacter jejuni
143
Possibly enterotoxin-mediated diarrhea, invades mucosa of the colon but does not penetrate, sepsis rarely occurs, histologic damage to the mucosal surfaces of the jejunum
Campylobacter jejuni
144
Watery, foul-smelling diarrhea followed by bloody stools accompanied by fever and severe abdominal pain, from undercooked chicken
Campylobacter jejuni
145
Campylobacter jejuni: Antigenic cross-reactivity between oligosaccharides in bacterial capsule and glycosphingolipids on surface of neural tissues
Guillain–Barré Syndrome (GBS)
146
Campylobacter jejuni: Reactive Arthritis
Reiter's Syndrome
147
Campylobacter jejuni: Treatment
symptomatic, Erythromycin for severe cases
148
Campylobacter jejuni: Prevention
public health measures
149
Gram (-) rods, curved, comma-shaped, urease (+), microaerophilic
Helicobacter pylori
150
Urease (+) Bacteria
Proteus mirabilis, Klebsiella pneumoniae, Helicobacter pylori, Ureaplasma urealyticum
151
Helicobacter pylori: Location
stomach
152
Helicobacter pylori: Transmission
ingestion
153
Damages goblet cells of the gastric mucosa, production of large amounts of ammonia from urea by the organism's urease, ammonia neutralizes stomach acid
Helicobacter pylori
154
Helicobacter pylori: Diagnosis
EGD with biopsy, urease breath test, H. pylori stool antigen
155
Recurrent pain in the upper abdomen, frequently accompanied by bleeding into the GIT
Peptic Ulcer Disease
156
Helicobacter pylori: Disease Associations
gastric CA, MALT lymphomas
157
Helicobacter pylori: Triple Therapy
Bismuth salicylate + Metronidazole + Tetracycline, Ranitidine bismuth citrate + Tetracycline + Clarithromycin or Metronidazole, Omeprazole or Lansoprazole + Clarithromycin + Metronidazole or Amoxicillin
158
Helicobacter pylori: Quadruple Therapy
Omeprazole or Lansoprazole + Bismuth salicylate + Metronidazole + Tetracycline
159
Facultative gram (-) rods, lactose fermenter, urease (+), extended spectrum beta-lactamase (ESBL), large polysaccharide capsule
Klebsiella pneumoniae
160
Klebsiella pneumoniae: Location
upper respiratory tract, GIT
161
Klebsiella pneumoniae: Transmission
aspiration, inhalation, ascending spread of fecal flora
162
Klebsiella pneumoniae: Diseases
Necrotizing Pneumonia, UTI
163
Thick, bloody sputum (currant jelly), usually nosocomial
Necrotizing Pneumonia (Klebsiella pneumoniae)
164
Most common cause of pneumonia in alcoholics
Klebsiella pneumoniae
165
Klebsiella pneumoniae: Treatment
culture-guided, Cephalosporins ± Aminoglycosides
166
Non-lactose fermenting gram (-) rods, swarming, oxidase (-) H2S producer, urease (+), facultative
Proteus mirabilis
167
Urease hydrolyzes the urea in urine to form ammonia, raises pH producing alkaline urine, encourages the formation of struvite stones (magnesium-ammonium-phosphate)
Proteus mirabilis
168
UTI associated with nephrolithiasis, staghorn calculi form on renal calyces
Complicated UTI (Proteus mirabilis)
169
Proteus mirabilis: Treatment
TMP, Ampicillin, Quinolones (Philippines), surgery for large stones
170
Non-lactose fermenting gram (-) rods, oxidase (+), H2S non-producer, obligate aerobes, pyocyanin (blue-green), sweet grape-like odor, Cetrimide agar
Pseudomonas aeruginosa
171
Pseudomonas aeruginosa: Location
environmental water sources (hospital respirators and humidifiers, "sterile" fluids), skin, upper respiratory tract, colon (10%)
172
Pseudomonas aeruginosa: Transmission
water aerosols, aspiration, fecal contamination
173
Pseudomonas aeruginosa: Virulence Factors
endotoxin, exotoxin A, elastase, proteases, pyocyanin, verdoglobin
174
Pseudomonas aeruginosa Virulence Factors: Tissue necrosis, inactivates EF-2, type III secretion system facilitates exotoxin transfer
Exotoxin A
175
Pseudomonas aeruginosa Virulence Factors: Damages the cilia and mucosal cells
Pyocyanin
176
Pseudomonas aeruginosa Virulence Factors: Hemoglobin breakdown
Verdoglobin
177
Burn wound infections, hot tub folliculitis, skin graft loss, green nail syndrome, puncture wound osteomyelitis, pubic osteomyelitis (IV drug abusers), otitis externa (malignant in diabetics), chronic suppurative otitis media
Pseudomonas aeruginosa
178
Most common cause of otitis externa (malignant in diabetics), chronic suppurative otitis media
Pseudomonas aeruginosa
179
VAP, high-risk CAP, bronchiectasis, cystic fibrosis, typhitis (necrotizing enterocolitis), Shanghai fever (milder form of typhoid), peritonitis (peritoneal dialysis), UTI
Pseudomonas aeruginosa
180
3rd most common cause of nosocomial UTIs
Pseudomonas aeruginosa
181
Pseudomonas aeruginosa Sepsis: Hemorrhagic lesions
ecthyma gangrenosum
182
Pseudomonas aeruginosa Sepsis: Leukemia or lymphoma post chemo- or radiation therapy, severe burns
febrile neutropenia
183
Pseudomonas aeruginosa: Treatment Combinations
Ceftazidime + Amikacin, Piperacillin + Amikacin, Azlocillin + Ciprofloxacin
184
Pseudomonas aeruginosa: Treatment for refractory cases
Rifampin
185
Pseudomonas aeruginosa: Prevention
disinfection of water-related equipment, hand washing, prompt removal of catheters
186
Gram (-) rods, predominant anaerobe of the human colon, bowel trauma, perforation or surgery
Bacteroides fragilis
187
Infections commonly due to combinations of bacteria in synergistic pathogenicity, LPS with low endotoxic activity, capsule (antiphagocytic and anticomplement), foul-smelling discharge, short-chain FA products
Bacteroides fragilis
188
Bacteroides fragilis: Diseases
abdominal and cerebral abscesses, peritonitis
189
Bacteroides fragilis: Treatment
Metronidazole, Clindamycin, Cefoxitin, surgical drainage of abscess
