Bacteria gram negative

Question 1

Gram neg. “coccoid” rods include what?

Answer 1

H. Influenzae, Pasteurella, Brucella and Bordetella

Question 2

differentiating b/w N. meningitidis and N. gonorrhoeae?

Answer 2

Meningitiditis= Maltose fermenter Gonorrhoeae=nonfermenter (but does ferment Glucose)

Question 3

two subclasses of gram neg. Rods?

Answer 3

lactose fermenter and lactose nonfermenter

Question 4

two subclasses of gram neg. lactose fermenting rods?

Answer 4

slow vs fast

Question 5

List the gram neg. lactose fermenting rods with associated subclass

Answer 5

Fast: Klebsiella, E. Coli, Enterobacter (MacConKEE’s agar)Slow: Citrobacter, Serratia (also use MacConkey’s agar, just Crappy and Slowly)

Question 6

Subclasses of gram neg. Lactose nonfermenting rods?

Answer 6

oxidase + vs oxidase -

Question 7

List gram neg. Lactose nonfermenting rods and their associated subclass

Answer 7

Oxidase neg.: Shigella, Salmonella, Proteus, Yersinia (PYSS)Oxidase pos.: Pseudomonas

Question 8

List different kinds of oxidase + comma shaped gram neg. bacteria and how to differentiate them from the rest

Answer 8

Campylobacter Jejuni: (grows in 42 degree C) Vibrio cholerae: (grows in alkaline media) Helicobacter (Produces urease)

Question 9

EMB agar?

Answer 9

Another option used to grow lactose fermenting gram neg. (along with MacConkey’s). They grow as purple/black colonies. E. oil grows as purple colonies with green sheen.

Question 10

Differences b/w N. Meningitidis and Gonorrhoeae

Answer 10

Meningicocci: Maltose fermenters, has polysachharide capsule, Vaccine, Respiratory and oral secretions, Causes meningococcemia, meningitis, waterhouse-friderichsen syndrome, Prophylaxis with rifampin, cipro ceftriaxone for those in close contact, treatment with CeftriaxoneGonococci: Glucose fermenters, no polysaccharide capsule, no vaccine, STI, causes gonorrhea, septic arthritis, conjunctivitis in babies, PID, Fitz-Hugh curtis syndrome, prevention with condoms and treatment ceftriaxone (+azithromycin against chlamydia)

Question 11

H Influenzae:classification in lab algorithm?mode of transmission?Media it grows on?different disease it can cause?Other?

Answer 11

-coccoid gram neg. rod -aerosols-Chocolate agar with factor V (NAD+) and X (hematin)-HaEMOPhilus causes: Epiglottis, Meningitis, Otitis media, Pneumonia -HiB is most invasive type

Question 12

Legionellamode of transmission?Media it grows on?different disease it can cause?Other?

Answer 12

-aerosol transmission from environmental water source habitat-charcoal yeast extract cultured with iron and cysteine -legionnaire’s disease: severe pneumonia, fever, GI and CNS symptoms-Pontiac fever: mild flu-like syndrome -Treat with macrolides or quinolone. -Lab can show hyponatremia

Question 13

P. aeruginosaclassification in lab algorithm?mode of transmission?different disease it can cause?Other?

Answer 13

• lactose non-fermenting oxidase +-Water source-PSEUDOH- Pneumonia, Sepsis, External otitis (malignant in diabetics)/Ecthyma gangrenosum (rapidly progressive necrotic cuteaneous lesions caused by bacteremia…seen in immunocompromised ppl), UTI, Diabetic osteomyelitis, hot tub folliculitis-produces blue-green pigment
• treat with (depending on source) aminoglycosides ( gentamicin/tobramycin) plus extended spectrum penicillin (piperacillin, ticarcillin, cefepime) carbapenema (imepenem, meropenem) monobactams ( aztreonem), fluroquinolones (cipro), or multiparty res (colistin, polymyxin)

Question 14

Different types of E Coli

Answer 14

EIEC: Invasive dysentery; invades intestinal mucosa and causes necrosis and inflammation; clinical pic similar to shigellaETEC: Traveller’s diarrhea; heat labile and stable toxinsEPEC: Pediatric diarrhea; Adheres to apical surface and flattens villi preventing absorptionEHEC: Dysentery and possible HUS with O157:H7; Shiga-like toxin causes necrosis and inflammation and can sometimes incite cytokine response to lead to HUS (micro thrombi form on endothelium damaged by Toxin)…does not ferment sorbitol unlike the other E. Coli

Question 15

Klebsiellaclassification in lab algorithm?mode of transmission?different disease it can cause?Other?

Answer 15

-Fast Lactose fermenting gram neg.-intestinal flora that can cause lobar pneumonia in alcoholics and diabetics when aspirated. - You don’t drink or have diabetes, do you have Klebsiella?: NAA; nosocomial UTIs, Aspiration pneumonia, Abscesses on liver and lungs

Question 16

Salmonella vs Shigella

Answer 16

Salmonella: have flagella (SALMON swim), can disseminate hematogenously, antibiotics may prolong fecal exertion of organism, invades intestinal mucosa and causes a monocytic response, can cause bloody diarrheaShigella: no flagella, spreads cell to cell, antibiotics shorten duration of fecal excretion of organism, invades intestinal mucosa and causes PMN response, often causes bloody diarrhea

Question 17

Salmonella typhi

Answer 17

causes typhoid fever and only found in humans. characterized by rose spots on abdomen, fever, headache and diarrhea. Can remain in gallbladder and cause a carrier state.

Question 18

Campylobacter jejuniclassification in lab algorithm?mode of transmission?different disease it can cause?Other?

Answer 18

-oxidase + comma shaped gram neg. that grows in 42degrees celcius (hot like CAMPfire)- fecal-oral spread through foods such as poultry, meat, unpasteurized milk. -major cause bloody diarrhea, especially in children-common antecedent to GBS and reactive arthritis

Question 19

vibrio cholerae classification in lab algorithm?mode of transmission?different disease it can cause?Other?

Answer 19

• oxidase + comma shaped gram neg. that grows in alkaline media-unsanitary water; endemic in developing countries -Produces profuse rice-water diarrhea via cholera toxin that permanently activates protein G, inc. cAMP

Question 20

Yersinia

Answer 20

usually transmitted from pet feces, contaminated milk or pork. Causes mesenteric adenines that can mimic crohn’s dz or appendicitis

Question 21

H. Pylori

Answer 21

-oxidase + comma shaped gram neg. that is urease +. -causes gastritis and peptic ulcers in duodenum. risk factor for gastric adenocarcinoma and lymphoma.-treatment is triple therapy: PPI, clarithromycin and amoxicillin/flagyl

Question 22

leptospiraclassification?mode of transmission?different disease it can cause?Other?

Answer 22

-spirochete-found in water contaminated with animal urine - can cause photophobia with conjunctival suffusion (erythema without exudate)…Weil disease: severe form with jaundice and azotemia from liver and kidney dysfunction; fever, hemorrhage and anemia

Question 23

Borrelia Burgdorferi

Answer 23

-spread through tick bites (Ixodes tick; same as babesia)-LymeEarly localized: erythema migrans, flu-like symptoms, +/-facial nerve palsyEarly disseminated: arthralgias, polyneuritis, 3rd degree heart block Late disseminated: migratory polyarthritis, polyneuropathy, encephalopathy, B/L FACIAL NERVE PALSYTreatment: doxycycline, ceftriaxone

Question 24

Treponema pallidum

Answer 24

Syphillis:-primary: painless chancre sore on genitals. If available, use dark-field microscopy to visualize treponemes influid from chancre B . Serologic testing: VDRL/RPR (non-specifc), confirm diagnosis with specific test (e.g., FTA-ABS)-secondary: 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).-Tertiary: Gummas (chronic granulomas), aortitis (vasa vasorum destruction), neurosyphilis (tabes dorsalis, “general paresis”), Argyll Robertsonpupil. Signs include broad-based ataxia,+ Romberg, Charcot joint, stroke without hypertension. For neurosyphilis: test spinal fluid with VDRLor RPR.Congenital syphillis:- Later presentation: Saber shins, saddle nose, CN VIII deafness, Hutchinson teeth, mulberry molars.-To prevent, treat mother early in pregnancy, as placental transmission typically occurs after first trimester.

Question 25

Argyll-Robertson pupil

Answer 25

Argyll Robertson pupil constricts with accommodation but is not reactive to light. Associated with 3° syphilis.(“prostitute pupil”: accommodates but does not react)

Question 26

VDRL false positive

Answer 26

VDRL detects nonspecific antibody thatreacts with beef cardiolipin. Inexpensive, widely available test for syphilis, quantitative, sensitive but not specific. Many false positives, including viral infection (e.g., mononucleosis [EBV], hepatitis), some drugs, and SLE.V: viruses (mono and hepatitis)D: drugs R: rheaumatic fever L: lupus antigen

Question 27

Anaplasma spp.-Dz-mode of transmission/source

Answer 27

-anaplasmosis with berry-like inclusion in granulocytes-ixodes ticks

Question 28

bartonella spp.-Dz-mode of transmission/source

Answer 28

-cat scratch dz, ancillary angiomatosis -cat scratch

Question 29

borrelia burgdorferi-Dz-mode of transmission/source

Answer 29

-lyme dz-ixodes ticks

Question 30

Borrelia recurrentis -Dz-mode of transmission/source

Answer 30

-recurrent fevers -louse

Question 31

Brucella spp.-Dz-mode of transmission/source

Answer 31

-Brucellosis-unpasteurized dairy

Question 32

campylbacter-Dz-mode of transmission/source

Answer 32

-bloody diarrhea -puppies and livestock (fecal-oral ingestion of undercooked meat)

Question 33

Coxiella burnetii-Dz-mode of transmission/source

Answer 33

-Q fever: presents as pneumonia with flu-like symptoms (with myalgia) and GI upset. - Aerosols of cattle/sheep amniotic fluid

Question 34

–Ehrlichia chaffeensis

Answer 34

• Erlichiosis with Monocytes with berry-like inclusions in cytoplasm - lone star ticks

Question 35

Francisella tularensis-Dz-mode of transmission/source

Answer 35

-Tularemia-ticks, rabbits, deer fly

Question 36

Leptospira spp.-Dz-mode of transmission/source

Answer 36

-leptospirosis-animal urine

Question 37

mycobacterium leprae-Dz-mode of transmission/source

Answer 37

-leprosy-humans with leprosy/armadillos

Question 38

Pasteurella multocida-Dz-mode of transmission/source

Answer 38

-cellulitis/osteomyelitis-animal bite, cats, dogs

Question 39

Typhus

Answer 39

• Rickettsia prowazekii (louse) or Rickettsia typhi (fleas)- Rash starting on Trunk (Typhus) and spreads out sparing palms and soles (so basically opposite of Rickettsii)

Question 40

RMSF

Answer 40

-Rickettsia rickettsii, spread through dermacentor ticks- found in South Atlantic states, especially NC. -triad: fever, headache and rash-Rash typically starts at wrists and ankles and then spread to trunk, palms and soles

Question 41

Yersinia pestis-Dz-mode of transmission/source

Answer 41

-plague -fleas (rats and prairie dogs are reservoirs)

Question 42

Gardnerella vaginalis

Answer 42

pleomorphic, gram-variable rod that is involved in vaginosis. Presents as a gray vaginal discharge with a fishy smell; nonpainful (vs. vaginitis). Associated with sexual activity,but not sexually transmitted. Bacterial vaginosis is also characterized by overgrowth of certain anaerobic bacteria in vagina. Clue cells, or vaginal epithelial cells covered with Gardnerella bacteria, are visible under the microscope Treatment: metronidazole or (to treat anaerobic bacteria) clindamycin.

Question 43

Chlamydiae-how does it replicate?-three important types, how they spread and their dz-treatment

Answer 43

-replicates by “Envading” as elementary form, then when in cell, it changes to Reticulate form. This allows it to undergo replication by fission and break down into multiple elementary forms-chlamydia pneumoniae: aerosols to cause pneumonia-C. psittaci: aerosols from parrots/other birds to cause Psittacosis pneumonia-C. trachomatis: causes PID, reactive arthritis (reiters syndrome) (can’t climb a tree), nongonococcal urethritis (can’t pee), conjunctivitis (can’t see)-treatment: azithromycin or doxy

Question 44

Chlamydia trachomatis serotypes

Answer 44

ABC: African, Blindness, Chronic dz…can cause follicular conjunctivitis typically seen to lead to blindness in africa…and can also cause chronic infxnD-K: PID/urethritis, neonatal pneumonia (staccato cough…can’t say “weeeeee”), neonatal conjunctivitis L1, L2 and L3: Lymphogranuloma Venereum- starts out as painless ulcers in genitals/anus and leads to painful inguinal lymph nodes that ulcerate. Treat with DOXY

Question 45

mycoplasma

Answer 45

Class: no cell wall, no gram stain, pleomorphic. Sterols for stability.
Transmission: close quarters, most common in lose cells.
Tx w/ macrolides, doxy, or Fluoro. NO pen bc no cell wall