Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Microbiology > Microbio-Bacterias > Flashcards

Microbio-Bacterias Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
0
Q

Bacterial virulence factors - What does IgA protease do? Which organisms secrete it?

A

Enzyme that cleaves IgA. Secreted by Strep. pneumoniae, H. influenza type B, and Neisseria.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
1
Q

Bacterial virulence factors: what does Protein A do? What organism expresses it?

A

Protein A binds to the Fc Region of IgG. It prevents opsonization and phagocytosis. Expressed by S. aureus.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Bacterial virulence factors- role of M protein? It is expressed by which organism(s)?

A

Helps prevent phagocytosis. Expressed by group A streptococci.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is a type III secretion system, and who uses it? Aka-injectosome (4)

A

Needle-like protein appendage facilitating direct delivery of toxins from certain G (-) bacteria: pseudomonas, Salmonella, Shigella, E. coli, to eukaryotic host cell.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Organism that infects prosthetic devices and intravenous catheters by producing adherent biofilms. Component of normal skin flora; contaminates blood cultures. Novobiocin sensitive.

A

Staphylococcus epidermidis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Organism that is second most common cause of uncomplicated UTI in young women (first E. Coli). Novobiocin resistant.

A

Staphylococcus saprophyticus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Lancet-shaped, gram-positive diplococci. Encapsulated. IgA protease.
Assoc. with appearance of Rusty Colored Sputum, sepsis in sickle cell anemia and splenectomy. No virulence without capsule.

Most common cause of MOPS.

A

Streptococcus pneumoniae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Optochin resistant (vs. S. Pneumoniae), alpha-hemolytic, part of normal flora of the oropharynx and cause dental caries, and subacute bacterial endocarditis at damaged valves.

A

Viridans group streptococci - Streptococcus mutans, S. Sanguinis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

JONES criteria for rheumatic fever. Causes pharyngitis, cellulitis, impetigo. Toxigenic-scarlet fever, toxic shock-like syndrome, necrotizing fasciitis. Immunologic-rheumatic fever, acute glomerulonephritis. Bacitracin sensitive. Antibodies to M protein enhance host defenses. ASO titer detects recent infection.

A

Streptococcus pyogenes (group A streptococci).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Presentation of skin rash with sandpaper-like texture, strawberry tongue, circumoral pallor.

A

Scarlet Fever

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Bacitracin resistant, beta-hemolytic, colonized vagina; causes pneumonia, meningitis, and sepsis, mainly in babies. Produces CAMP factor. Screen pregnant women at 35-37 weeks. Patients with positive culture receive intrapartum penicillin prophylaxis.

A

Streptococcus agalactiae (group B streptococci)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Normal part of colonic flora that are penicillin-G resistant and cause UTI, biliary tract infections and subacute endocarditis (following GI/GU procedures). Vancomycin-resistant enterococci are an important cause of nosocomial infection. Can grow in 6.5%NaCl and bile test.

A

Enterococci (group D streptococci) - Enterococcus faecalis and E. faecium)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Colonizes the gut. Can cause bacteremia and subacute endocarditis in colon cancer patients.

A

Streptococcus bovis- (group D streptococci)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

(G+) rods- exotoxin encoded by beta-prophage. Potent exotoxin inhibits protein synthesis via ADP-ribosylation of EF-2. Symptoms include pseudomembranous pharyngitis (grayish-white membrane) with lymphadenopathy, myocarditis, and arrhythmias. Black colonies on cysteine-telluride agar.

A

Corynebacterium diphtheriae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Cleaves releasing proteins for neurotransmitters; paralysis from Renshaw cells in spinal cord. Causes spastic paralysis, trismus (lockjaw), and risus sardonicus.

A

Clostridium tetani

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Produces a preformed, heat-labile toxin that inhibits ACh release at the NMJ. In adults usually caused by ingestion of preformed toxin in canned foods. In babies, due to ingestion of spores in honey causing floppy baby syndrome. **spore former

A

Clostrium botulinum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Produces alpha-toxin (“lecithinase” a phospholipase) that can cause myonecrosis and hemolysis (gas gangrene). **spore former

A

Clostridium perfringens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Produces 2 toxins- Toxin A, enterotoxin binds to the brush border of the gut. Toxin B, cytotoxin, causes cytoskeletal disruption via actin depolymerization–> pseudomembranous colitis–>diarrhea. Often secondary to antibiotic use. Tx metronidazole or oral vancomycin.

A

Clostridium dificile

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

G (+) spore forming rod - only bacterium with a polypeptide capsule (contains D-glutamate). Boil like lesion –> ulcer with black eschar –> uncommonly progresses to bacteremia and death.

A

Cutaneous anthrax - Bacillus anthracis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

G (+) spore forming rod - only bacterium with a polypeptide capsule (contains D-glutamate). Inhalation of spores –> flu like symptoms that rapidly progress to fever, pulmonary hemorrhage, mediastinitis, and shock. Aka- Woolsorter’s disease.

A

Pulmonary anthrax

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Gram (+) Causes food poisoning. Causes watery, non-bloody diarrhea and GI pain within 8 hrs. Associated with reheated rice. **spore former

A

Bacillus cereus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Only G(+), facultatative intracellular microbe that produces LPS; acquired by ingestion of unpasteurized dairy products and deli meats, via transplacental transmission, or by vaginal transmission during birth. –>neonatal meningitis Charac. rocket tails that allow for tumbling mobility. Can cause spontaneous abortions in pregnancy.

A

Listeria monocytogenes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Organism with branching filaments resembling fungi. G(+) Anaerobe, not acid fast, part of normal oral flora, causes oral/facial abscesses that drain through sinus tracts, forms yellow “sulfur granules”. Tx with penicillin

A

Actinomyces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Organism with branching filaments resembling fungi. G(+) Aerobe, weakly acid fast, found in soil, causes pulmonary infections in imunocompromised and cutaneous infections after trauma in immunocompetent. Tx with sulfonamides

A

Nocardia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Acid fast organism. Symptoms include fever, night sweats, weight loss, and hemoptysis. Cord factor in virulent strains inhibits macrophage maturation and induces release of TNF-alpha. Sulfatides (surface glycolipids) inhibit phagolysosomal fusion.

A

Mycobacterium:
M. tuberculosis (TB, often resistant to multiple drugs).
M. kansasii (pulmonary TB-like symptoms).
M. avium-intracellulare (causes disseminated, non TB disease in AIDS.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Acid-fast bacillus that likes cool temperatures (infects skin and superficial nerves - “glove and stocking” loss of sensation) cannot be grown in vitro. Reservoir in US: armadillos. Presents diffusely over the skin, with leonine facies, and is communicable; charac. by low cell-mediated immunity with a humoral Th2 response.

A

Mycobacterium leprae- Leprosy (Hansen disease) Lepromatous. Tx: clofazimine for 2-5 years

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Acid-fast bacillus that likes cool temperatures (infects skin and superficial nerves - “glove and stocking” loss of sensation) cannot be grown in vitro. Reservoir in US: armadillos. Limited to a few hypoesthetic hairless plaques; characterized by high cell-mediated immunity with largely Th1-type immune response.

A

Mycobacterium leprae- Leprosy (Hansen Disease) Tuberculoid - Tx: consists of multi drug therapy: dapsone and rifampin for 6 months.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Gram negative diplococci, produces IgA proteases. 2 types:

A

Neisseria:
Gonococci

Meningococci

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Ferments glucose only. No polysaccharide capsule; no maltose fermentation; no vaccine (due to rapid antigenic variation of pious proteins); sexually transmitted, causes gonorrhea, septic arthritis, neonatal conjunctivitis, pelvic inflammatory disease, and Fitz-Hugh-Curtis syndrome. Erythromycin ointment prevents neonatal transmission.

A

Neisseria gonococci

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Ferments: maltose and glucose. Polysaccharide capsule; maltose fermentation; vaccine (none for type B), respiratory and oral secretions. Causes meningococcemia and meningitis, Waterhouse-Friderichsen syndrome. Tx: Ceftriaxone or penicillin G. When patient has meningitis, presents with púrpura formation on the skin.

A

Neisseria: meningococci

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Small gram-negative (coccobacillary) rod; aerosol transmission. Most invasive disease caused by capsular type B. Produces IgA protease. Culture on chocolate agar with factor V and X (10). Known for epiglottitis (cherry red in children), meningitis, otitis media, and pneumonia. Does NOT cause the flu.

A

Haemophilus influenzae

31
Q

G(-) rod, stains poorly-use silver stain. Grow on charcoal yeast extract culture with iron and cysteine. Detected clinically with presence of antigen in urine. Aerosol transmission from environmental water source habitat. No person to person transmission. Causes: severe pneumonia, fever, GI and CNS symptoms.

A

Legionella pneumophila - legionnaires’ disease

Pontiac fever= mild flu-like syndrome.

32
Q

Aerobic G(-) rod. Non-lactose fermenting oxidase [+]. Produces pyocyanin (blue-green pigment); has a grape like odor. Water source. Produces endotoxin (fever, shock), and exotoxin A (inactivates EF-2). Assoc. w/wound and burn infections, Ecthyma gangrenosum- rapidly growing necrotic tissue, pneumonia in CF, sepsis, external otitis, UTI, drug use, diabetic osteomyelitis, and hot tub folliculitis.

A

Pseudomonas aeruginosa

33
Q

Virulence factors: fimbriae- cystitis and pyelonephritis; K capsule- pneumonia, neonatal meningitis; LPS endotoxin-septic shock. Microbe invades intestinal mucosa and causes necrosis and inflammation. Clinical manifestations similar to Shigella.

A

E. Coli- EIEC: invasive; dysentery

34
Q

Virulence factors: fimbriae- cystitis and pyelonephritis; K capsule- pneumonia, neonatal meningitis; LPS endotoxin-septic shock. Produces heat-labile and heat-stable enterotoxins. No inflammation or invasion.

A

E. coli- ETEC: traveler’s diarrhea (watery)

35
Q

Virulence factors: fimbriae- cystitis and pyelonephritis; K capsule- pneumonia, neonatal meningitis; LPS endotoxin-septic shock. No toxin produced. Adheres to apical surface, flattens villi, prevents absorption.

A

E. coli - EPEC: diarrhea usually in children (pediatrics).

36
Q

Virulence factors: fimbriae- cystitis and pyelonephritis; K capsule- pneumonia, neonatal meningitis; LPS endotoxin-septic shock. O157:H7 is the most common serotype. Produces Shiga-like toxin that causes Hemolytic-uremic syndrome. Microthrombi form on endothelium damaged by toxin–> mechanical hemolysis (schistocytes formed) and decrease renal blood flow; microthrombi consume platelets–> thrombocytopenia.

A

E. coli - EHEC
Dysentery (toxin alone causes necrosis and inflammation).
Does not ferment sorbitol (distinguishes it from other E. coli).

37
Q

An intestinal flora that causes lobar pneumonia in alcoholics and diabetics when aspirated. Very mucoid colonies caused by abundant polysaccharide capsules.
CF: patient presents Red “currant jelly” sputum. Also cause nosocomial UTIs. 4 A’s…

A

Klebsiella- 4 A’s: Aspiration pneumonia
Abscess in lungs and liver
Alcoholics
di-A-betics

38
Q

Organism that does not ferment lactose, can cause bloody diarrhea, invades intestinal mucosa and causes a monocytic response. Antibiotics may prolong fecal excretion of the organism. Produces hydrogen sulfide and has many animal reservoirs. Have flagella and can disseminate hematogenously.

A

Salmonella

39
Q

Does not ferment lactose, often causes bloody diarrhea, invades mucosa and causes PMN infiltration. Antibiotics shorten duration of fecal excretion of organism. Does NOT produce hydrogen sulfide. Only reservoirs are humans and primates. Cell to cell transmission; no hematogenous spread. No flagella.

A

Shigella

40
Q

Causes typhoid fever. Found only in humans. Characterized by rose spots on the abdomen, fever, headache, and diarrhea. Can remain in gallbladder and cause carrier state.

A

Salmonella typhi

41
Q

Major cause of bloody diarrhea, especially in children. Fecal oral transmission through foods such as poultry, meat, unpasteurized milk. Comma or S-shaped, oxidase [+], grows at 42*C. Common antecedent to Guillain-Barré syndrome and reactive arthritis.

A

Campylobacter jeujuni

42
Q

Produces profuse rice-water diarrhea via enterotoxins that permanently activates Gs, increases cAMP. Comma shaped, oxidase [+], grows in alkaline media. Endemic to developing countries. Prompt oral rehydration is necessary.

A

Vibrio cholerae

43
Q

Gram (-) Usually transmitted from pet feces (puppies), contaminated milk, or pork. Causes messengering adenitis that can mimic Crohn disease or pseudoappendicitis. Produces H2S.

A

Yersenia enterocolitica

44
Q

Causes gastritis and peptic ulcers (especially duodenal). Risk factor for peptic ulcer, gastric adenocarcinoma and lymphoma. Curved G(-) rod that is catalase, oxidase, and urease [+] (can use urea breath test for Dx). Creates alkaline environment. Most common initial treatment is triple therapy: PPI + clarithromycin + either amoxicillin or metronidazole.

A

Helicobacter pylori

45
Q

Spiral shaped bacteria with axial filaments and include Borrelia, Leptospira, and Treponema.

A

Spirochetes

46
Q

Found in water contaminated with animal urine. Causes myalgias (classically in calves), flu-like symptoms, jaundice, photophobia with conjunctival suffusion (erythema without exudate). Prevalent among surfers and in tropics (i.e., Hawaii).

A

Leptospira interrogans or leptospirosis

47
Q

This infection causes severe jaundice and azotemia from liver and kidney dysfunction; fever, hemorrhage, and anemia. Found in water contaminated with animal waste residues. What is it’s clinical agent and aka?

A

Icterohemorrhagic leptospirosis - aka: Weil’s disease

48
Q

Disease transmitted by Ixodes (also a vector for Babesia). Natural reservoir is the mouse. Mice are important for the tick life cycle, common in NE US. Symptoms: Erythema Chronicum Migrans; flu-like symptoms, +- facial nerve palsy. Late symptoms: monoarthritis (large joints) and migratory polyarthritis, cardiac AV nodal block, neurologic (encephalopathy, facial nerve palsy, polyneuropathy).

A

Lyme disease- caused by Borrelia burgdorferi

49
Q

Localized disease presenting with painless chancre. Dark field microscopy can be used to visualize organism in fluid from chancre. Serologic testing VDRL/RPR (non-specific), confirm diagnosis with specific test (e.g. FTA-ABS).

A

Caused by Treponema pallidum - Primary syphilis.

50
Q

Disseminated disease with constitutional symptoms, maculopapular rash (palms and soles), condylomata lata (also confirmable with dark-field microscopy). Serologic testing VDRL/RPR (non-specific), confirm diagnosis with specific test (e.g. FTA-ABS).

A

Treponema pallidum- secondary syphilis

Secondary syphilis- Systemic. Latent syphilis ([+] serology without symptoms) follows.

51
Q

Gummas (chronic granulomas), aortitis (vasa vasorum destruction), neurosyphilis (tabes dorsalis, “general paresis”), Argyll Robertson pupil.
Signs: broad-based ataxia, [+] Romberg, Charcot joint, stroke without hypertension.

A

Treponema pallidum - Tertiary syphilis

For neurosyphilis: test spinal fluid with VDRL or RPR.

52
Q

Saber shins, saddle nose, CN VIII deafness, Hutchinson teeth, mulberry molars. Prevention can be acquired by treating mother early in pregnancy, as placental transmission typically occurs after first trimester.

A

Congenital syphilis

53
Q

Argyll Robertson pupil: what is it, and what is associated with it?

A

The pupil constricts with accommodation but is not reactive to light. Associated with tertiary syphilis.

AKA- prostitute pupil- accommodates but does not react.

54
Q

What is VDRL?

A

Test for detection of treponema pallidum.
**may create false positives because it detects nonspecific antibody that reacts with beef cardiolipin. For:
Viruses (mono, hepatitis)
Drugs
Rheumatic fever
Lupus and Leprosy

55
Q

What is the Jarisch-Herxheimer reaction?

A

Flu-like syndrome after antibiotics are started- due to killed bacteria releasing pyrogens.

56
Q

A pleiomorphic, gram-variable rod that is involved in vaginosis. Presents as gray vaginal discharge with a fishy smell; nonpainful (vs. vaginitis). Assoc. with sexual activity, but not sexually transmitted. Clue cells, or vaginal epithelial cells covered with the bacteria, visible under the microscope. What microorganism is this, and what is the treatment?

A

Gardnerella vaginalis

Tx-Metronidazole or clindamycin

57
Q

Ixodes ticks (vectors are deer and mice). Granulocytes with morulae in cytoplasm.

A

Anaplasma spp.

58
Q

Cat scratch disease?

A

Bartonella spp.

59
Q

Organism that causes relapsing fever. Transmission source are louse (recurrent due to variable surface antigens).

A

Borrelia recurrentis

60
Q

Gram (-) Organism associated with unpasteurized dairy- causes undulant fever.

A

Brucella spp.

61
Q

Organism that causes Q fever; no arthropod vector: tick feces and cattle placenta release spores that are inhaled as aerosols of cattle/sheep amniotic fluid. Presents as pneumonia. **spore former

A

Coxiella burnetii

62
Q

Rash is usually rare during infection. Organism is found in Lone star ticks that cause appearance of monocytes with morulae (berry-like inclusions) in cytoplasm.

A

Ehrlichia chaffeensis

63
Q

Organism associated with ticks, rabbits, and deer fly- causes Tularemia.

A

Francisella tularensis

64
Q

Gram (-) Organism associated with animal bite, dogs, cats: causes cellulitis, osteomyelitis

A

Pasteurella multocida

65
Q

This organism produces headache, fever, and a rash that typically starts at wrists and spreads to trunk, palms, and soles. Obligate intracellular organisms that need CoA and NAD+ because they cannot synthesize ATP. Most common in North Carolina.

A

Rocky Mountain Spotted Fever - Richettsia rickettsii

66
Q

Organism that starts centrally (trunk) and spreads out, sparing palms and soles. One type is endemic to fleas, one to ticks, and one is epidemic in human body louse. What are they??

A

Typhus:
Flea- Richettsia typhi
Louse- Richettsia prowazekii
Tick- Richettsia rickettsii

67
Q

Obligate intracellular organism (can’t make its own ATP), that cause mucosal infections. Two forms: elementary body, and reticulate body. Causes reactive arthritis (Reiter’s Syndrome), follicular conjunctivitis, nongonococcal urethritis, and PID. Giemsa stain.

A

Chlamydia trachomatis

68
Q

Obligate intracellular organism (can’t make its own ATP), that cause mucosal infections. Two forms: elementary body, and reticulate body.
Both of these strains cause atypical pneumonia, transmitted by aerosol. Giemsa stain.

A

C. Pneumonia and C. Psittaci

69
Q

Lymphogranuloma venereum- small, painless ulcers on genitals –> swollen, painful inguinal lymph nodes that ulcerate (“buboes”). What is the microorganism, the subtype, and treatment?

A

Chlamydia trachomatis serotype L1, L2, and L3.

Treat with doxycycline.

70
Q

Classic cause of walking pneumonia (insidious onset, headache, nonproductive cough, patchy or diffuse interstitial infiltrate). X-Ray looks worse than patient. High titer of cold agglutinins (IgM), which can agglutinate or lose RBCs. Grown on eaton agar. Penicillin ineffective since the organism has no cell wall.

A

Mycoplasma pneumoniae

71
Q

What is this organism: bone of child with sepsis, on top of the bone, on the metaphisis of the bone: yellowish area, looks like an abscess - osteomyelitis . In addition, this child has sickle cell.

A

Salmonella
Why is it on metaphisis of bone? BC most of the blood supply is supplied there and the mechanism of spread is hematogenous (comes from another source and then it gets to the bone).

72
Q

What is seen when you have a focal myocardial inflammation with multinucleate giant cells?

A

Aschoff bodies (rheumatic fever)

73
Q

This microorganism produces a cord factor (serpentine cord) appearance in virulent XXX strains. It activates macrophages (promoting granuloma formation) and induces release of TNF-alpha. Sulfatides (surface glycoproteins) inhibit phagolysosomal fusion. What microorganism is this??

A

Mycobacteria spp.

74
Q

This infection can be chronic where it can cause blindness (due to follicular conjunctivitis in Africa). What is the microorganism and the subtype?

A

Chlamydia trachomatis - Types A, B, and C.

75
Q

This infection can cause Urethritis/PID, ectopic pregnancy, neonatal pneumonia, (staccato cough) with eosinophilia, neonatal conjunctivitis (1-2wks after birth). What is the microorganism and the subtype?

A

Chlamydia trachomatis

Types: D-K

Microbiology (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions