board review microbiology bacteria

Question 1

cause of trench fever

Answer 1

Bartonella quintana

reservoir is humans

vector is lice.

self limited

Question 2

Bartonella quintana

REservoir?

Vector?

is the disease self limited

Answer 2

human = reservoir

vector = lice

self limited

Question 3

On the boards

painless violaceous nodule on the skin with fever in an HIV pt.

has a cat

Answer 3

Bacillary angiomatosis

dont confuse with kaposi sarcoma

TRICK:

BACILLARY ANGIOMATOSIS = neutrophilic infiltrate

Kapsoi sarcoma = Lymphocytic infiltrate

Question 4

bacteroides fragilis

is a common normal Gi flora (strict anarobe) –>

periotonitis and serios anaerobic infections (GI and pelvic abscesses) no bowel sound.

tx?

Answer 4

metronidazole 1st line

clindamycin2nd line

Question 5

two important microaerophilic

Answer 5

*H pylori

campylobacter jejuni

Question 6

what is the only known microorganism that can thrive in the highly acidic environment of the stomach

Answer 6

H pylori

Question 7

on the board.

pt with recurrent UTIand stag horn struvite kidney stone.

Ammonium magnesium phosphate (struvite stone)

Answer 7

Proteus mirabilis

Question 8

Q on boards

Both klebsiella and Proteus mirabilis

can cause Stag horn struvite kidney stones.

how can you tell the difference bw the two?

Answer 8

question will tell you

Lactose fermenter (Klebsiella)

Question 9

Q on boards

pt with Proteus mirabilis kidney stone. whats the treatment

Answer 9

ceftriaxone

or

TMP/SMX + gentamicin

Question 10

Q on boards

a pt w/ recurrent UTIs, now presents with fever, N/V, flank pain, hematuria

whats the cause?

Answer 10

Proteus mirabilis

Question 11

Q on boards

male pt with burning pee,

negative culture for ghonorrhea and chylamdia.

Urease +.

cause???

Answer 11

Ureaplasma urealyticum

urethritis in MALES (if neither gonococcus or chlamydia identified)

Question 12

painful genital ulcer with exudate “pus” and unilateral painful swollen lymphadenopathy (bubo) draining pus.

what is STI

** whats the treatment??

Answer 12

Haemophilus ducreyi (chancroid)

TX: ***Azithromycin

or

cetriaxone

Question 13

immigrant

child with drooling, hoarseness, sit in a “sniffing position” with

body leaned forward and head and nose tiled forward/upward

enriched chocolate agar.

diagnosis?

Answer 13

epiglottis

due to Haemophilus influenza type B

Question 14

the polysaccharide b capsule vaccine induced immune response only works in a person over what age?

this is the H influ type B vaccine

Answer 14

only induces immune response in children > 18 months

this is why it was ineffecive in protecting children younger than 18.

Question 15

for the boards

meningitis during the first 3 months (is due to microorganism acquired during passage) list most common

Answer 15

1, Grp B strept

2. E. coli
3. Listeria monocytogenes

Question 16

on the boards

look for pt with sudden onset of headache, confusion, watery diarrhea, and severe pneumonia

cause?

Answer 16

legionella pneumophila

Question 17

trick boards questions

where do legionella pneumophila multiply?

Answer 17

macrophages in the alveoli

phagocytosed by macrophages and multiple –> enter the alveoli –> pneumonia

Question 18

Q on boards

pt with HA, confusion, watery diarrhea and severe pneumonia

labs: hyponatremia.

(legonella)

whats the tx?

Answer 18

*Erythromycin.

first aid: macrolides (azithromycin) and fluoroquinolones (levofloxacin)

Question 19

Q on the boards

what is the SAFE immunization in pregnancy for bordetella pertussis?

Answer 19

DTAP

Question 20

on the boards

pt from _eastern europ_e who is living on a farm and eating unpasteurized milk (usually goat cheese) is seen with a fever (going on for months) that rises in the morning and falls at night(undulant fever) with *sweating*,

muscle aches and arthritis (*** bilateral Sacroiliitis***)

Answer 20

Brucella

Question 21

brucella

will invade the reticuloendothelial system and induce granuloma in the lymph nodes, liver, spleen and ?

Answer 21

bone marrow

diagnosis: bone marrow, blood culture, or positive bengal rose rxn (demonstration of antibodies w/ ELISA)

Question 22

tx for brucella

and there side effects

Answer 22

tx with both

doxycycline (can cause drug induced lupus)

Gentamicin (nephrotoxicity, ototoxicity)

Question 23

name the uresase pathogens for the boards

Answer 23

cryptococcus (an opportunistic meningitis in HIV pt, inc CSF opening pressure)

Klebsiella pneumonia –> red sputum- look for alcoholics, diabetics or pts w/ chronic lung disease

H pylori

Proteus mirabilis –> recurrent UTI –> staghorn stone

Ureaplasma urealyticum –> urethritis in Males ( if neither gonoccous or chlamydia identified)

Question 24

on the boards

pt from arkansas (or oklahoma, missouri) presents with Black based ulcers on his arms and enlarged lymph nodes.

he is handling rabbit products

oculoglandular, typhoidal (mouth), pneumonic w/ the formation of granulomatous lesion in the lung, spleen liver.

what treatment should you do?

A. aspirate the LN

B. give streptomycin and dont aspirate

Answer 24

do NOT aspirate the LN - highly infectious

give streptomycin

diagnosis = tularemia

ulcers commonly present on hand.

Question 25

first line tx for pasteurella multocida?

Answer 25

**avoid suturing** animal bite woulds tx: **amoxicillin clavulanate** from combank - if pt has sulfa or penicillin allergy give doxycyclin.

Question 26

Yersinia pestis Reservoir? human gets infect how? leading to 3 complications?

Answer 26

reservoir is **rodents** **flee bites human** **pneumonic, septicemic,** or the **bubonic plaques**

Question 27

yersinia pestis bubonic plaque presentation **Question!** how would you treat?

Answer 27

**_enlarged LN_** **_black necrotic skin lesions (black death)_** **invades lungs, liver, spleen** also from combank: fever, cough, dyspnea, hemoptysis, painful lymphadenopathy. can lead to DIC, necrosis of finger tips and tip of nose. TX: **streptomycin** (aminoglycosides) , **tetracycline**

Question 28

culture of the lymph gland aspirate shows gram negative **rod** w/ **bipolar staining (saftey pin appearance)** what organism

Answer 28

**yersinia pestis**

Question 29

what is the route of transmission or infection with **yersinia enterocolitica**

Answer 29

**fecal oral route** or **raw unpasteurized milk.** - may cuase diarrhea (enterotoxin in the ileum) in kids \< 5

Question 30

Q on boards yersinia enterocolitica can cause **colonic ulceration --\>** dysentery (bloody diarrhea) in adults, what complication will it cause if it spreads?

Answer 30

**liver** and **splenic absecces**

Question 31

question on boards what type of patients are susceptible to **yersinia enterocolitica**

Answer 31

**hemochromatosis** and **hemolytic anemia** pts bc it is **siderophilic (iron loving) bacteria**

Question 32

Q on boards yersinia enterocolitica is associated with what type of arthritis?

Answer 32

**reactive arthritis (reiters syndrome)**

Question 33

all of the following can cause reactive arthritis except? (aspriate joint and not septic) how do you sterilize joint before aspriation? **yersinia** **chlamydia trachomatis** **shigella** **campylobacter infection** **gonorrhea.**

Answer 33

**gonorrhea** **sterilize joint - chlorhexadine**

Question 35

**H pylori** causes **intestine lgastric adenocarcinoma** or **diffuse type**

Answer 35

**​intestinal type gastric adenocarcinoma** not diffuse (linitis plastica)

Question 36

trick Q on boards pt that has H pylori infection, now diagnosed with **MALT lymphoma** how shouuld you treat the lymphoma? A. give chemo B. give PPI C. tx the H pylori infection

Answer 36

**treat the H pylori infection** **(amoxicillin, clarithromycin** and **PPI)** if pt allergic to penicillin use metronidazole. which in turn will cure the MALT lymphoma

Question 37

Q on boards what bacterial infection precedes **reactive arthritis** and **guillian barre syndrome?**

Answer 37

**campylobacter jejuni**

Question 38

what two bacteria cause appendicitis like signs

Answer 38

**yersinia enterocolitica** * pet feces * dysentery (bloody diarrhea) * precedes reactive arthritis (reiters syndrome) **campylobacter jejuni** * unpasteurized milk * diarrhea bloody * precedes guillain barre syndrome

Question 40

**Q : tx for bacteroides fragilis** a common normal GI flora (strict anerobe) --\> peritonitis and serious anaerobic infections (GI and pelvic abscess)- **no bowel sounds**

Answer 40

**metronidazole** ## Footnote if metronidazole isnt answer choose **clindamycin**

Question 41

Q on boards (trick) presents as a **painless violaceous nodule** on the skin with **fever** in a **HIV** patient. examation of the nodule shows **neutrophilic** infiltrate . nodule shown in exhibit below. what is the cause?

Answer 41

**bacillary angiomatosis** in **AIDS** pt dont confuse with **kaposi sarcoma** (less acute than bacillary angiomatosis and usually macular) **Kaposi** will have **Lymphocytic infiltrate (**not neutrophilic)

Question 42

tx of bacillary angiomatosis in AIDs pt?

Answer 42

**erythromycin** +/- **rifampin** ## Footnote sketchy says azithromycin and doxycycline

Question 43

on boards rash that is macular, papular, annular or follicular​ pt with a hx of **painless gential ulcer** healed 6 weeks ago and started to have generalized rash including the **palms** and **soles** diagnosis ?

Answer 43

**secondary syphilis**

Question 44

on the boards pt diagnosed with tiertary syphilis Gummas (tumor like balls of inflammation/granulomas) involving: soft tissue, CNS, bone, cardiovascular \* pt develops an **aortic aneurysm** with no hx of cardiovascular risk. what is the pathophysiology in the development of this?

Answer 44

syphilitic aoritits --\> destruction of the **VASA VASORUM** (supplying nutrition to the aortic wall) --\> **aortic aneurysm**

Question 45

on the boards pt presents with loss of vibration sense, discriminative touch, and proprioception in the lower extremties as well as unsteadiness while eyes are closed **+ romberg sign** on further question he says he had a STI 10 years back and said it went away on its on what is the cause

Answer 45

**Tabes dorsalis ​** caused by untreated syphilis. degeneration of nerves of the dorsal column (fasciculus **gracilis)** note trick!!! romberg test is only positive in dorsal column damage not cerebellar.

Question 46

Q on boards what is the only treatment for neurosyphilis? PCN-G \*\*\* what if the patient has **allergy to PCN**

Answer 46

**desensitize** and **treat w/ PCN**

Question 47

there will be a + **quellung rxn** in ?

Answer 47

**capsulated bacteria**

Question 48

**epidermolytic toxin A and B (exfoliative toxin)** are responsible for what in gram + cocci

Answer 48

**SSSS** **staphylococcal scalded skin syndrome**

Question 49

pt presents with fever, septic shock, **confusion**, diffuse erythemaotus rash, **desquamation** on the **palms** and **soles,** vomiting, diarrhea - **hypotension** puritic maculopapular lesions on the extremities you diagnose **toxic shock syndrome toxin-1** what is the mechanism

Answer 49

**superantigen activates CD4 Th cells** which stimulate cytokine release the above mechanism is caused by staph a. (lethal) also can be caused by Exotoxin **A** and **C** of strept pyogenes

Question 50

how does staph epidermidis virulent factor work

Answer 50

produces **Glycocalyx** forms a hydrophobic **biofilm** which is adhesive to foreign surfaces (valves and catheters)

Question 51

for boards the most common causative organism of **cystitis** in a young healthy **pregant** women as well as postpartum endometritis/bacteremia is?

Answer 51

**group B strept agalactiae** tx penicillin or ampicillin

Question 52

explain how **protein A** (virulence factor) attributes to the pathogenicity of staph aureus

Answer 52

**protein A** binds ot the **Fc portion** of **IgG** at the complement binding site **preventing** the **activation of complement**

Question 53

for the boards **community acquired MRSA** it colonizes the nasopharynx and skin in close contact setting. look for pt with **recurrent cellulitis** or **boils** (contact sports, military recruits, native americans, gays, iv drug user, prison. what is the treatment

Answer 53

**trimethoprim-sulfamethoxazole (FIRST LINE)** **doxycycline** **clindamycin**

Question 54

what is the most important virulence factor of strept pyogenes (GRP A )

Answer 54

**M protein** protects it from phagocytosis and inhibiting complement activation.

Question 55

on the boards pt with redness and swelling of the extremity with **bullae** and **enlarged lymph nodes**

Answer 55

**erysipelas** caused by strep pyogenes

Question 56

on the boards look at a **post-surgical patient** in the **icu** with **fever, hypotension, skin rash**, and **implanted device** or **young women** presented with these symptoms during menstruation and using tampon diagnosis.

Answer 56

**TSS ​** either caused by staph or strept.

Question 57

**on the boards** blood cultures for Toxic shock sydrome are \_\_\_\_ for staph a. \_\_\_\_ for strept pyogenes

Answer 57

**\*\*\*\*\*\*\*\*NEGATIVE** for **staphylococcal TTS** ## Footnote **positive = streptococcal TSS ​**

Question 58

on the boards severe infections with **S. Pneumoniae** are seen in pts with (MM, Asplenia, SS) \*\* alcoholism or hypogammaglobulinemia look for a pt with **fatal pneumococcal bacteremia** and **disseminated intracappilary coagulopathy (DIC)** due to ?

Answer 58

**lack of IgG** (required for opsonization).

Question 59

boards pt with **UTI, sepsis, endocarditis** and **traunsurethral resection** of the **prostate (TURP)** grows on **6.5% salt broth (NaCL)** and **bile** cause?

Answer 59

**enterococci (Grp D** streptocci)

Question 60

what is the leading cause of invasive bacterial respiratory disease in pts with HIV?

Answer 60

**Stept pneumoniae** not PJP

Question 61

what are you IgA protease secreting bacteria

Answer 61

**Strept pneumonia** **N gonorrhea** **N meningitidis** **H influ type B**

Question 62

High yield which streptococcus viridans subtype produces **_dextrans_** from sucrose --\> bacteria adherence to **_FIBRIN_** -platelets aggregates on **_damaged_ heart valves** what type of endocarditis this causes TX?

Answer 62

strept **sanguinis** causes subacute endocarditis it also can cause dental enamel caries TX: penicillin and aminoglycosides

Question 63

**strept mutans** can cause caries how?

Answer 63

**fermentation of sugar --\> lactic acid** (deminieralization of enamal)

Question 64

Question on boards not in first aid **Peptostreptococcus** are **anaerobic**, multiform, gram + non-spore forming bacteria, commensal organism, mainly in mouth look for pt with **periodontal disease** or **difficulty in swallowing** **(post stroke or ALS who presents with cavitary pneumonia**) what can this microbe cause?

Answer 64

**\*\*\*lung abscess\*\*\*** brain, liver, breast abcesses in **immunocompromised pts.**

Question 65

true or false. there is **no** increased risk for listeria infection in pt with immunoglobulin or complement deficiency ?

Answer 65

**true**

Question 66

for the boards what microbe gram + **aerpboc rod "chinese letter appearance"** black colonies on potassium tellurite cytoplasm contains metachromatic granules that stain with aniline dyes

Answer 66

**corynebacterium diphtheria**

Question 67

for the boards **diphtheria toxin** works how? and what other microbe uses the **virulence factor exotoxin AB** to do the same thing

Answer 67

**ADP-ribosylate** the **host EF-2** --\> inhibition of protein synthesis and cell death.. **P. aeruginosa.**

Question 68

contraceptive intrauterine devices inc the risk for GU infections with?

Answer 68

**actinomyces israelii**

Question 69

beaded branching filamentous and weakly acid fast. first presents with **lung infection** (cavitary) then spread to form **brain abscess** in pts with cell mediated immunosuppression know that this bacteria can also cause **mycetoma** (chornic foot infection --\> bone and soft tissue sinuses what bacteria does this

Answer 69

nocardia

Question 70

trick question **which neisseria** has a capsule? N meningitidis: (maltose and glucose oxidzer) N. Gonorrhoeae: (only glucose oxidizer)

Question 71

Q on boards the most common cause of **ophthalmia neonatorum** occurs in the **first five days.** **bilateral purulent discharge**

Answer 71

**Neisseria gonorrhoeae**

Question 72

currant jelly **stool** in a previously healthy 7-10 month infant your thinking?

Answer 72

**intussusception**

Question 73

**on boards** alcoholic pt with pneumonia in the upper lobe complaining of cough with a bloody "currant jelly" sputum

Answer 73

**Klebsiella pneumonia**

Question 74

pwhwich batteria is the **only** toxiicogenic bacterial diarrhea in which antibiotics significantly shorten the duration of the disease ?

Answer 74

**vibrio cholerae** TX: tetracyclines, **rehydration w/ glucose and sodium**

Question 75

**neutropenia** --\> pseudomonal bacteremia --\> **ecthyma gangrenosum** (pseudomonal sepsis in very ill pt) look for a **rounded indurated black lesion** with **central ulceration** tx with ?

Answer 75

**antipseudomonal antibiotics**

Question 76

**pyoderma gangrenosum.** asoociated with vasculitis, RA, Myelofibrosis, multiple myelome, and crohns disease TX with?

Answer 76

**prednisone.**

Question 77

the cause of pneumonia in **cystic fibrosis** **or** **nosocomial infections** in pts with **ventilatory support** your thinking the cause is?

Answer 77

**pseudomonas**

Question 78

TX of pseudomonas which cepholosporins cant be used\*\*\*

Answer 78

**antipseudomonal penicillin (piperacillin)** and **aminoglycosides** or **ciprofloxacin** (fluoroquinolones) can use: **ceftazidime, cefepine** canT use: **ceftriaxone or cefuroxime**

Question 79

on boards pt living in new york and has spreading erythematous rash with raised border and central clearing at the site of a bite. **erythemia chronicum migrans** what stage of lymes disease is this? do you need to do serology test?

Answer 79

**stage 1** do **not** need to do serology tx with Doxycycline,

Question 80

on the boards **pt**presents with **polyarthiritis, headache, meningitis,** and **cranial neuritis** and **bells palsy**

Answer 80

**stage 2 lyme disease**

Question 81

pt who lives in NY and presents with heart problems although he has no history of cardiac disease he is diagnosis with lymes disease. what is the heart condition

Answer 81

**3rd degree AV block**

Question 82

on the boards. pt with a **fever** that **starts every 8 days** then **breaks** with **excessive sweat** and **rash** commonly have **splenomegaly** what is the diagnosis and what are the symptoms and relapsing fever due to?

Answer 82

**borrelia recurrentis** the relapse of the fever and symptoms is due to antigen variation (the immune system does not recognize the change antigen)

Question 83

what are the two intracellular parsites that require the host ATP for replication

Answer 83

chlamydia and rickettsia

Question 84

pt with recent hx of tick bite who has **rash** on **palms** and **soles** spreading **proximally** to the **trunk** with **fever, arthralgia, headache** and **inc LFTs** \*\*\*what is the diagnosis what is treatment?

Answer 84

**rickettsia rickettsii** tx: doxycycline or chloramphenicol (during pregnancy)

Question 85

what are the 6 infections that cause **rash** on the **palm** and **soles**

Answer 85

**rocky mountain spotted fever** **toxic shock syndrome** **meningococcemia** **coxsackie A** **secondary syphilis**

Question 86

on the boards **cattle farmer (cattle slaughterer,** or around animals during delivery) who presents with a **sudden onset fever** and **dry cough (atypical pneumonia)** what is the severe complication of this infection?

Answer 86

diagnosis **coxiella burnetii (Q fever)** develop **endocarditis (chronic)** evaluate with TEE tx with tetracycline.

Question 87

pt with pneumonia that had a **gradual onset, pharyngitis an hoarseness of voice** sinusitis frequently with the pneumonia. you used what to diagnosis **chlamydia pneumoniae** how would you treat this

Answer 87

diagnose with giemsa stain to identiy the **intracytoplasmic inclusions -** however know that **PCtR** is the **standard test** **doxy or azithromycin**

Question 88

Q on boards **pet shop worker** or **veterinarians** (\*\* with **parrotts)** with **atypical pneumonia** what is diagnosis and how would you treat how does it spread

Answer 88

**chlamydia psittaci** **TX: doxxycyline** bacteria shed from feces of birds (parrots) to respiratory track

Question 89

**TRICK ON BOARDS** you treat a pt for **chlamydia psittaci** with **doxycycline** however the pt is not responding to doxy and still has symptoms of pneumonia what is the new diagnosis

Answer 89

**histoplasmosis** note if it was the other way around and the patient wasnt responding to amphoterin B then it would be chlamydia psittaci

Question 90

mycoplasma pneumonia can cause - hemolytic anemia. what is the mechanism

Answer 90

**B cell** response --\> antibodies (Ig**M** **cold agglutinins)** react with "**I**" antigen on RBCs at low temp 4 degree C --\> hemolysis

Question 91

what are some extrapulmonary manifestations of mycoplasma pneumonia 1. on boards: pt with red ear drum and painful

Answer 91

**1._Bullous myringitis_** others **splenomegaly.**, arthritis, and CNS changes mainly **confusion**.

Question 92

Q on boards presents as **cervical lymphadenitis** in children. localized to lymphatic tissue possible exposure to mycobacterium Q: diagnosis Q: how do you treat?

Answer 92

**M. Scrofulaceum** **Node excision w/out chemo**

Question 93

boards **pt** who has a **non healing skin ulcer** on the **hands** following trauma and is working around **fish tanks (**fish tank granuloma) diagnosis? tx?

Answer 93

**M. marinum** **rifampin** and **ethambutol** (resistant to isoniazid)