Sheet2-表格 1 Flashcards
What are 2 disease processes caused by Viridans strep and what species are responsible?
1) dental caries: Strep.mutans
2) bacterial endocarditis: Strep. Sanguis
What are 2 options for triple treatment of H.
pylori?
(1) bismuth (Pepto-Bismal),metronidazole, and tetracyclin or amoxicillin. OR
(2) metronidazole, omeprazole, and clarithromycin (#2 is more expensive)
What are 3 advantages/differences between VDRL and FTA-ABS?
FTA-ABS is
1) more specific
2) positive earlier in disease
3) remains positive longer than VDRL
What are 3 disease processes caused by Strep. pyogenes?
1) Pyogenic–pharyngitis,cellulitis, skin infection
2) Toxigenic–scarlet fever, TSS
3) Immunologic–rheumatic fever, acute
glomerulonephritis
What are 4 biological false positives for VDRL?
1) Viruses (mono, hepatitis)
2) Drugs
3) Rheumatic fever and rheumatic arthritis
4) Lupus and leprosy (=VDRL)
What are 4 clinical symptoms of ‘walking’ pneumonia?
1) insidious onset
2) headache
3) nonproductive cough
4) diffuse interstitial infiltrate
What are 4 clinical symptoms of TB?
1) fever
2) night sweats
3) weight loss
4) hemoptysis
What are 5 areas that can be affected by extrapulmonary TB?
1) CNS (parenchmal tuberculoma or meningitis)
2) Vertebral body (Pott’s disease)
3) Lymphadenitis
4) Renal
5) GI
What are the culture requirement for H. flu?
culture on chocolate agar with factor V (NAD) and X (hematin).
[Think: ‘Child has ‘flu’; mom goes to five (V) and dime (X) store to buy
chocolate.’]
What are the lab findings with Chlamydia?
cytoplasmic inclusions on Giemsa fluorescent antibody stains smear
What are the symptoms of RMSF? (3)
1) rash on palms and soles (migrating to wrists, ankles, then trunck)
2) headache
3) fever
What are the three stages of Lyme disease?
1) erythema chronicum migrans, flu-like symptoms
2) neurologic and cardiac manefestations
3) autoimmune migratory polyarthritis
What are the two forms of chlamydia?
1) Elementary body (small, dense): Enters cell via endocytosis
2) Initial or Reticulate body: Replicates in the cell by fission
What are the two forms of leprosy (or Hansen’s disease)?
1) lepromatous- failed cellmediated immunity, worse
2) tuberculoid- self-limited.
What are two drugs that could be used to treat ‘walking’ pneumonia?
tetracycline or erythromycin
What are two drugs that could treat Chlmydia?
erythromycin or tetracycline
What are two lab findings associated with ‘walking’ pneumonia?
1) X-ray looks worse than patient
2) High titer of cold agglutinins (IgM)
What are usually associated with pseudomembraneous colitis?
Clostridium difficile; it kills enterocytes, usu. is overgrowth secondary to antibiotic use (esp. clindamycin or ampicillin)
What bacteria are G+, sporeforming, anaerobic bacilli?
Clostridia
What bacteria causes a malignant pustule (painless ulcer); black skin lesions that are vesicular papules covered by a blak eschar?
Bacillus anthracis
What bacteria exhibits a ‘tumbling’ motility, is found in unpasteurized milk, and causes meningitis in newborns?
Listeria monocytogenes
What bacteria is catalase(-) and bacitracin-resistant?
Strep. agalactiae
What bacteria is catalase(-) and bacitracin-sensitive?
Strep. pyogenes
What bacteria is catalase+ and coagulase+?
Staph. aureus
What bacteria produces alpha-toxin, a hemolytic lecithinase that causes
myonecrosis or gas gangrene?
Clostridium perfringens
What bacterium causes Cellulitis?
Pasteurella multocida
What bacterium causes leprosy?
Mycobacterium leprae
What bacterium causes Lyme disease?
Borrelia burgdorferi
What bacterium causes the Plague?
Yersinia pestis
What bacterium causes Tularemia?
Francisella tularensis
What bacterium causes Undulant fever?
Brucella spp. (a.k.a. Brucellosis)
What bug causes atypical ‘walking’ pneumonia?
Mycoplama pneumoniae
What bug causes gastroenteritis and up to 90% of duodenal ulcers?
Helicobacter pylori
What bug causes Legionnaire’s disease?
Legionella pneumophila
What bug is associated with burn wound infections?
Pseudomonas aeruginosa
What bug is comma- or Sshaped and grows at 42C, and causes bloody diarrhea with fever and leukocytosis?
Campylobacter jejuni
What bug that causes diarrhea is usually
transmitted from pet feces (e.g. puppies)?
Yersinia enterocolitica
What causes tetanus? (give bacteria and disease process)
Clostridium tetani: exotoxin produced blocks glycine release (inhibitory NT) from Renshaw cells in spinal cord
What causes the flu?
NOT H. flu -it is caused by influenza virus
What chemical is found in the core of spores?
dipicolinic acid
What coccobacillus causes vaginosis: greenish vaginal discharge with a fishy smell;
nonpainful?
Gardnerella vaginalis
What disease does Bordetella perussis cause? How?
Whooping cough: toxin permanently disables G-protein in respiratory mucosa (turns the ‘off’ off); ciliated epithelial cells are killed; mucosal cells are overactive
What disease does Vibrio cholerae cause? How?
Cholera: toxin permanently activates G-protein in intestinal mucosa (turns the ‘on’ on) causing rice-water diarrhea
What disease is caused by Borrelia?
Lyme Disease
What disease is caused by Clostridium botulinum? What pathophys. does it cause?
Botulism: associated with contaminated canned food, produces a preformed, heat labile toxin that inhibits ACh release—> flaccid paralysis.
What diseases (2) are caused by Treponema?
- Syphilis (T. pallidum)
- Yaws (T. pertenue; not and STD)
What diseases can be caused by Staph. aureus?
- Inflammatory disease: skin infections, organ abscess, pneumonia
- Toxinmediated disease: Toxic Shock Syn., scalded skin syndrome (exfoliative toxin), rapid onset food poisoning (enterotoxins)
What do Chlamydia trachomatis serotypes A, B, and C cause?
chronic infection, cause blindness in Africa (ABC= Africa / Blindness / Chronic
What do Chlamydia trachomatis serotypes D-K cause? (3)
- urethritis/ PID
- neonatal pneumonia
- neonatal conjuctivitis
What do Chlamydia trachomatis serotypes L1,L2, and L3 cause?
lymphogranuloma venereum (acute lymphadentis: positive Frei test)
What do RMSF, syphilis, and coxsackievirus A infection have in common?
rash on palm and sole is seen in each (coxasackievirus A =hand, foot, and mouth disease)
What does catalase do? Which bacteria have it?
It degrades H2O2, an antimicrobial product of
PMNs.
- Staphlococci make catalase; Strep. do NOT.
What does the H-antigen represent?
H: flagellar antigen, found on motile specie
What does the K-antigen represent?
K: capsular, relates to virulence
What does the O-antigen represent?
O-antigen is the polysaccharide of endotoxin (found on all species)
What does VDRL detect? (It detects non-specific antibody that reacts with what?)
detects antibody that reacts with beef cardiolipin
What drug of choice is used to treat Norcardia? Actinomyces? (Acronym: SNAP)
Sulfa for Norcarida, Actinomyces gets Penicillin
What enteric bacterial infection may be prolonged with antibiotic treatment?
Salmonellosis
What enzyme allows H. pylori to create an alkaline environment?
urease (cleaves urea to ammonia); used in urease breath test
What family includes E. coli, Salmonella, Klebsiella, Enterobacter, Serratia, and
Proteus?
Enterobacteriaceae
What family of bacteria uses the O-, K-, and H-antigen nomenclature?
Enterobacteriaceae
What function does the capsule serve? (2: one for the bacterium, one other)
1) antiphagocytic
2) antigen in vaccines (Pneumovax, H. flu B, meningococcal vaccines)
What G+ anaerobe causes oral/facial abscesses with ‘sulfur granules’ that may
drain through sinus tracts in skin?
Acinomyces israelii
What G+ and also weakly acid fast aorobe found in soil causes pulmonary infections
in immunocompromised patients?
Norcardia asteroides
What general type of bacteria are normal flora in GI tract but pathogenic elsewhere?
Anaerobes
What general type of bacteria grow pink colonies on MacConkey’s agar?
Lactose-fermenting enteric bacteria
What is a Ghon complex and in whom does it occur?
- Occurs in Primary TB (usually a child)
- Ghon complex= draining Hilar nodes and Ghon focus, exudative parenchymal lesion (usu. in LOWER lobes of lung)
What is a lab diagnosis of diphtheria based on?
G+ rods with metachromatic granules; grows on tellurite agar. (Coryne=club shaped)
What is a major difference between Salmonella and Shigella observable in the lab?
- Salmonella are motile;
- Shigella are nonmotile
What is a positive Quellung reaction?
if encapsulated bug is present, capsule SWELLS when specific anticapsular antisera are added.
What is notable about Chrmydia psittaci?
has an avian reservoir
What is one reason M. leparae infects skin and superficial nerves?
It likes cool temperatures
What is the classic symptom of Lyme Disease?
erythema chronicum migrans, an expanding ‘bull’s eye’ red rash with central clearing.
What is the classic triad of symptoms associated with Rickettsiae?
1) headache
2) fever
3) rash (vasiculitis)
What is the common manifestation of secondary TB?
Fibrocaseous cavitary lesion usu. in APICIES of lung
What is the common site of infection for Mycobacterium tuberculosis?
the apicies of the lung (which have the highest PO2)
What is the D.O.C. to treat Gardnerella vaginalis?
Metroidazole
What is the DOC for treating rickettsial infections?
tetracycline
What is the DOC for treatment of most rickettsial infections?
tetracycline
What is the DOC to treat Lyme Disease?
tetracycline
What is the DOC to treat syphilis?
Penicillin G
What is the drug of choice for H. flu meningitis? What DOC for prophylaxis in closecontacts?
Treat meningitis with CEFTRIAXONE; Rifampin for prophylaxis.
What is the drug of choice for Legionaires’ disease?
Erythromycin
What is the morphology of H. flu?
Small G(-) (coccobacillary) rod
What is the morphology of H. pylori?
Gram (-) rod
What is the primary drug used to treat leprosy?
dapsone (toxicity is hemolysis and methemoglobinemia)
What is the recommended treatment for Pseudomonas aeruginosa infection?
aminoglycoside plus extended-spectrum penicillin (e.g. piperacillin or ticarcillin)
What is the source of infection and the bacterium that causes endemic typhus?
R. typhi; from fleas
What is the source of infection and the bacterium that causes epidemic typhus?
R. prowazekii; from human body louse
What is the source of infection and the bacterium that causes Q fever?
Coxiella burnetii; from inhaled aersols
What is the source of infection and the bacterium that causes Rocky Mountain
Spotted Fever?
Rickettsia rickettsii; from tick bite
What is the toxin responsible for TSS is Staph. aureus?
TSST-1; it is a superantigen that binds to class II MHC and T-cell receptors—> polyclonal T-cell activation
What is the unique component found in
Mycoplamsa bacterial membranes?
cholesterol
What is the unique feature of Chlamydiae cell walls?
its peptidoglycan wall lacks muramic acid
What is woolsorter’s disease?
inhalation anthrax; can cause life-threatening pneumonia
What lab test assays for antirickettsial antibodies?
Weil-Felix reaction
What Lancefield Antigen Group are enterococci in?
Group D
What Lancefield Antigen Group are Viridans strep in?
They are non-typealbe. They do not have a C-carbohydrate on their cell wall to be classified by.
What level of disinfection is required to kill spores?
autoclaving; they are highly resistant to destruction by heat and chemicals
What populations are most likely to get Mycoplama pneumoniae infection?
- patients younger than age 30
- military recruits
- prisons
What rickettsial disease is atypical in that it has no rash, no vector, negative Weil-Felix reaction, and its causative organism can survive outside for a long time?
Q fever (Coxiella burnetii)
What species are associated with food poisoning in contaminated seafood?
Vibrio parahaemolytica and Virbrio vulnificus
What species causes diphtheria?
Corynebacterium diptheriae
What species is associated with food poisoning in improperly canned foods (bulging cans)?
Clostridium botulinum
What species is associated with food poisoning in meats, mayonnaise, and custard?
Staphylococcus aureus (this food poisoning usu. starts quickly and ends quickly)
What species is associated with food poisoning in poultry, meat, and eggs?
Salmonella
What species is associated with food poisoning in reheated meat dishes?
Clostridium perfringens
What species is associated with food poisoning in reheated rice?
Bacillus cereus (‘Food poisoning from reheated rice? Be serious!’)
What species is associated with food poisoning in undercooked meat and unpasteurized juices?
E. coli 0157-H7
What species of Mycobacteria causes pulmonary, TB-like symptoms?
M. kansasii
What strain of Haemophilus influenza causes most invasive disease?
capsular type b
What symptoms are associated with M.
scrofulaceum
cervical lymphadenitis in kids
What test differentiates Viridans from S. pneumoniae?
Viridans are resistant to optochin; S. pneu. are sensitive to optochin
What two bugs secrete exotoxins that act via ADP ribosylation of G-proteins, permanently activating adenyl cyclase (resulting in increased cAMP)?
- Vibrio cholerae
- Bordetella pertussis
What two genera of G+ rods form long branching filaments resembling fungi?
Acinomyces and Nocardia
What type of bacteria are difficult to culture, produce gas in tissue (CO2 and H2), and are generally foulsmelling?
Anaerobes
What type of bacteria is associated with rusty sputum, sepsis in sickle cell, and splenectomy?
Pneumoccocus
What type of E. coli are associated with bloody diarrhea?
enterohemmoragic/enteroinvasive E. coli
What type of immunologic response is elicited by a Salmonella infection?
monocyte response
What types of infection can chlamydia cause? (4)
- arthritis
- conjunctivitis
- pneumonia
- nongonococcal urethritis
What virulence factor of Staph. aureus binds Fc-IgG, inhibiting complement fixation and phagocytosis?
Protein A
What virulence factor of Strep. pyogenes also serves as an antigen to which the host makes antibodies?
M-protein
What will likely be visible under the microscope in the case of Gardnerella vaginallis infection?
Clue cell, or vaginal epithelial cells covered with bacteria
Where are Viridans strep. found (reservoir)?
normal flora of oropharynx
Where are when is Lyme disease common?
common in northeast US in summer months
Which disease/toxin causes lymphocytosis? (Cholera or Pertussis)
Pertussis toxin: by inhibiting chemokine receptors
Which has an animal reservoir? (Salmonella or Shigella)
Salmonella: poultry, meat, eggs
Which is more specific for syphilis: VDRL or FTA-ABS?
FTA-ABS is more specific
Which is more virulent? (Salmonella or Shigella)
Shigella (10^1 organisms)
vs.
Salmonella (10^5 organisms)
Which is motile? (Salmonella or Shigella)
Salmonella (think: salmon swim)
Which species of chlamydia causes and atypical pneumonia? How is it transmitted?
- C. pneumonia
- transmitted via aerosol
Which two species of chlamydia infect only
humans?
- C. trachomatis
- C. pneumoniae
Why are anaerobes susceptible to oxygen?
they lack catalase and/or oxidase and are susceptible to oxidative damage
Why does TB usually infect the upper lobes of the lung?
M.tuberculosis is an aerobe; there is more oxygen at the apicies
Why must rickettsia and chlamydia always be intracellular?
they can’t make their own ATP
Are most fungal spores asexual?
yes
Are most P. Carinii infections symptomatic?
no, most of are asymptomatic
Are the above mentioned systemic mycoses dimorphic?
yes, except coccioidomycosis which is a spherule in tissue
How do the S. Schenckii yeast appear in the pus?
Cigar-shaped budding yeast
How do you diagnose cryptosporidium?
cysts on acid fast stain
How do you diagnose giardiasis?
Trophozoites or cysts in stool
How do you get P. Carinii?
Inhalation
How do you treat systemic mycoses?
fluconazole or ketoconazole for local infection,
amphotericin B for systemic infection
How do you Tx S. Schenckii?
Itraconazole or Potassium Iodide
How does Aspergillus appear microscopically?
Mold with septate hyphae that branch at a V-shaped (45 degree angle) , they are NOT dimorphic
How does Mucor species appear microscopically?
It is a mold with irregular nonseptate hyphae branching at wide angles>90 degrees
How does Paracocciodioidomycosi
Captain’s wheel’ appearance (like on a sailboat)
How is Clonorchis sinensis transmitted and what disease results?
undercooked fish; causes inflammation of the biliary tract
How is Schistosoma transmitted and what disease results?
snails are host; cercariae penetrate skin of humans; causes granulomas, fibrosis, and inflammation of the spleen and liver
How is Ancylostoma Duodenale transmitted and what disease results?
Larvae penetrate skin of feet; intestinal infection can cause anemia
How is Ascaris Lumbricoides transmitted and what disease results?
Eggs are visible in feces; intestinal infection
How is cryptosporidium transmitted?
Cysts in Water
How is Dracunculus medinensis transmitted and what disease results?
In drinking water; sink inflammation and ulceration
How is E. granulosis transmitted and what disease results?
Eggs in dog feces cause cysts in liver; causes anaphylaxis if echinococcal antigens released from cysts
How is E. Histolytica transmitted?
Cysts in Water
How is Enterobius Vermicularis transmitted and what disease results?
food contaminated with eggs; intestinal infections; causes anal pruritus
How is giardia transmitted?
Cysts in Water
How is Loa loa transmitted and what disease results?
Transmitted by deer fly; causes swelling the in the skin (can see worm crawling in conjunctiva)
How is malaria dx?
Blood smear
How is malaria transmitted?
mosquito (Anopheles)
How is Onchocerca volvulus transmitted and what
transmitted by female blackflies; causes river
blindness
How is Paragonimus Westermani transmitted and what disease results?
Undercooked crab meat; causes inflammation and secondary bacterial infection of the lung
How is Sporothrix schenckii appear under the scope?
Dimorphic fugus that lives on vegetation
How is Strongyloides Stercoralis transmitted and what disease results?
larvae in soil penetrate the skin; intestinal infection
How is T. Canis transmitted and what disease results?
food contaminated with eggs; causes granulomas (if in retina=blindness)
How is T. Solium transmitted and what disease results?
undercooked pork tapeworm; causes mass lesions in the brain, cysticercosis
How is T. Vaginalis transmitted?
sexually
How is Toxo transmitted?
cysts in meat or cat feces
How is Trichinella Spiralis transmitted and what disease results?
undercooked meat, usually pork; inflammation of muscle, periorbital edema
How is Wucheria transmitted and what disease results?
female mosquito; causes blockage of lymphatic vessels (elephantiasis)
In what cells do you find histoplasmosis?
macrophages
Is Pneumocystis Carinii a yeast?
Yes, but originally classified as a Protozoa
Microscopically how does Candida appear?
budding yeast with pseudohyphae, germ tube
formation at 37 degrees C)
Name 3 Trematodes (Flukes) .
Schistosoma, Clonorchis sinensis, Paragonimus Westermani
Name 4 opportunistic fungal infections.
Candida Albicans, Aspergillus fumigatus, Cryptococcus Neoformans, Mucor and Rhizopus species
Name 4 systemic mycoses.
Coccidiomycosis, Histoplasmosis, Paracoccidioidomycosis, Blastomycosis
Name two asexual spores transmitted by inhalation.
Hisoplasmosis and Coccidiodomycosis
Name two Cestodes (Tapeworms) .
Taenia Solium, and Echinococcus Ganulosus
What agar is used to culture for systemic mycoses?
Sabouraud’s Agar
What are Conidia?
asexual fungal spores (ex. Blastoconidia, and
arthroconidia)
What are some common Candida infections?
Thrush in Immunocompromised pts (neonates, patients on steroids, diabetics and AIDS pts) , endocarditis in IV drug users, vaginitis (high pH, Diabetes, post-antibiotic), diaper rash, disseminated candidiasis (to any organ)
What are some infections caused by cryptococcus?
Cryptococcal meningitis, cryptococcosis
u r the best~!
u r my dear love~!
What are the 10 Nematodes (roundworms) we are concerned with?
Ancylostoma duodenale (hookworm) , Ascaris Lumbricoides, Enterobius Vermicularis (pinworm), Strongyloides stercoralis, Trichinella Spiralis, Dracunculus Medinensis, Loa loa, Onchocerca Volvulus, Toxocara Canis, Wucheria Bancrofti
What are the 4 B’s of Blastomycosis?
Big, Broad-Based, Budding
What are the diseases caused by Cryptosporidium?
Severe diarrhea in AIDS, Mild disease (watery diarrhea) in non-HIV
What are the diseases caused by Toxoplasma?
Brain Abscess in HIV and birth defects
What are the infections caused by aspergillus?
Ear fungus, Lung cavity Aspergilloma (‘fungus ball’), invasive aspergillosis.
What can systemic mycoses mimic?
TB (granuloma formation)
What disease are caused by Entamoeba Histolytica?
Amebiasis: bloody diarrhea, dysentery, liver abscess, RUQ pain
What disease does Mucor species cause?
Mucormycosis
What disease does Pneumocystis carinii cause?
Pneumocystis Carinii Pneumonia
What disease does Sporothrix Schenckii cause?
Sprotricosis
What disease does Trypanosoma Cruzi casue?
Chaga’s Disease (heart disease)
What disease is caused by Giardia Lamblia?
Giardiasis: bloating, flatulence, foul-smelling diarrhea
What disease is caused by Leishmanina donovani?
Visceral Leishmaniasis (Kalaazar)
What disease is caused by P. Carinii?
Diffuse interstitial pneumonia in HIV
What disease is caused by the plasmodium species (vivax, ovale, malariae, falciparum) ?
Malaria: cyclic fever, headache, anemia,
splenomegaly
What disease is caused by Trypanosma Gambiense and Rhodesiense?
African Sleeping sickness