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Microbiology SJSM > Block 2 (Santosh's review) > Flashcards

Block 2 (Santosh's review) Flashcards

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1
Q

Chlamydia trachomia (Harry Potter)

Niche

Strains
ABC
D-K
L1,2,3

Feature

VF

Tests

(“HP’s CUTe CAT PuRs LouD in the morNinG”)

A

Humans

ABC= Trochoma (a very serious eye infection that can lead to blindness (trichiasis))

D-K = Neonatal conjunctivitis & pneumonia, Adult (cervicitis, urethritis, prostatitis)

L1-3= LGV (lymphoma granulomatous venerum

Feature= It forms HP (Halbertaedter-prowzek) bodies (these store glycogen)

VF= No peptidoglycan wall means its resistant to B-lactam antibiotics (cefuroxime)

Tests= Giema staining shows the HP inclusion bodies

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2
Q

Actinomyces Nocardia:
- Nocardia brasiliensis
- Nocardia ostitidis vaviarum

Causes what infection?

Tests (BAMS)

Treatment?

(“ACT NAtural & Don’t Panic… BAMS!!”)

A

Causes Actinomycotic mycetoma (chronic + slow progressive granulomatous infection of the skin, connective tissue, & bone forming swollen discharging sinuses (yellow granules)

Tests=
- Modified Brown-Brenn (shows gram-negative & branching)
- Acid-fast (1% sulphuric acid or 3% HCL in 95% ethanol)
- Sabourain agar & Brain heart infusion

Treat= surgically drain sinuses, then use a large dose of penicillin

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3
Q

Actinomyces Israelii

Causes what infection?

Tests (BAMS)

Treatment?

(“ACTIng in MAY then ….BAMS Dead Profession”)

A

Causes= Actinomycosis (from a tooth abscess/infection in the mandible with yellow-sulphur granules and inflammation)

Tests=
- Brain-heart infusion agar
- Acid-fast staining
- modified Brown-Brenn test shows gram-negative branching organisms)
- Sabouraund’s agar

Treat= drain + penicillin

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4
Q

Legionella

Nich

Causes what infection?

Tests (BAMS)

Treatment?

(“PLEasE WIPe your Loins”)

A

Gram-negative bacilli

Niche= water + amoebas

Causes=

Legionellosis (Legionnaires disease= L. pneumophila Look for atypical pneumonia + fever, headache, confusion, focal neuro def, scanty non-purulent sputum, hypernatremia)

Mild legionellosis NO PNEUMONIA (Pontiac fever = fever, headache, myalgia)

Tests= Immunofluorescent stain (antisera-direct) & urine ELISA (antigen detection)

Treat= Legionnaires (a high dose of erythromycin or fluoroquinolones as an alternative (Levofloxacin)
&
Pontiac fever = self-limiting

Predispotions= alcoholic liver cirrhosis, smoking, AIDS, & hospitalization

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5
Q

Vibrio cholera

Causes what infection?

Pathogenesis

Tests

Treatment?

(“NOt Good, ViCtory FACes GIrls ToDay”)

A

Gram-negative motile, oxidase-positive, halophilic, bacilli

Causes= food poisoning (sudden onset of effortless vomiting & profuse watery diarrhea (rice water-stool)

Patho= v. cholera is ingested and multiplies in the small intestine –> releases cholera toxin to increase Adenylate cyclase and increase cAMP production to inhibit G-inhibitory protein and cause more salt and water loss into the bowels (diarrhea)

Tests= alkaline peptone water growth, non-lactose fermenting (pale on MacConkeys), sensitive to TCBS, ferments glucose

Treat= IV rehydration and tetracycline (or cotrimoxazole)

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6
Q

Psittacosis (aka parrot fever) chlamydia

Niche

Causes what?

Tests

Treat

“PArrots Have Great ColourFul Dives”

A

Niche= birds

IP ~14 days cause atypical pneumonia + hepatitis (headache, fever, chills, myalgia, malaise, non-productive cough, rales

Tests= Giemsa stain (shows cytoplasmic inclusions), serodiagnosis via complement fixation test

Treat= doxycycline

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7
Q

Mycoplasm pneumoniae

Features

Causes what?

VF

Tests

Treat

(“My PEnis FEEls iTChy & AChy”)

A

Feat= pleomorphic/fried egg colonies

causes= Atypical pneumonia (low fever, chronic onset/recovery), tracheobronchitis, acute pharyngitis

VF= P1 antigen to adhere to a sialylated glycoprotein at the base of ciliated cells or the surface of RBCs (adherence to mucus membranes)

Tests=
- Animal serum (sterol) + yeast extract medium shows mulberry colonies
- Cold agglutination (insensitive/nonspecific)
- Compliment fixation test (high false positives)
- ELISA (IgG+M antibodies)

Treat= erythromycin + tetracylcine

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8
Q

Klebsiella granulomatosis (calymatobacterium) vs Klebsiella pneumoniae

Grams

Cause what?

Tests

Treatment

K. granulomatosis (“KiNG DONOVAN WRIGHT”)

K. Pneumonia (“Kill NyPD”)

A

Both are gram-negative, capsulated, motile bacilli

K.granulomatosis = Donovanosis (marked beefy red ulcers with rolled edges (painless)) shows Donovan bodies on wright’s stain (intracellularly)

K. peunomiae = pneumonia esp in alcoholics (Friedlander’s disease = upper lobes abscesses with currant jelly sputum)

Tests

MacConkeys + pink lactose fermeters = both
Giemsa stain & Wright’s stain show donovan bodies = k. granulomatosis

Treat doxycycline = both

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9
Q

pseudomonas aruginosa associated with cystic fibrosis

Gram

VF

Pathogenesis

Tests

Treat

“NOt Good, PiCk ANoTher Fruit To Peel”

A

gram-negative, motile oxidase + catalase positive, strict aerobic bacilli

VF= endo/exo-toxins, enzymes, pyocyanin (damages cilia)

Patho= patients with cystic fibrosis have reduced clearance capacities and are more at risk of p. aruginosa

Tests=
- MacConkeys (pale NLF colonies)
- Oxidase + catalase positive
- TSI (metallic sheen)
- Nutrient agar ( blue/green + fruity smell)
- pyocin + bacteria phage typing

Treat= ticarcillin or piperacillin & an aminoglycoside (gentamycin or ankimycin)

Prevent= keep neutrophil levels above 500 mew/L

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10
Q

Neonatal meningitis

Three organisms in descending order of likely hood s

Treatment
less than a month old
more than a month old

“NEonateS LoVe Alot”

A

E.coli
S. agalactia
L. monocytogenes

Look for=
Early: lethargy, hypotonia, vomiting
Late: Fontanelle bulging

Treat:
less than a month = ampicillin + aminoglycoside (gentamycin) or a 3rd gen cephalosporin (cefotaxime or ceftazidime (higher risk tho)
&
more than a month= vancomycin + a 3rd gen cephalosporin (cefotaxime or ceftriaxone)

Kid/adults classical triad fever, headache, neck stiffness)

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11
Q

Neonatal diarrhea

Three most common organisms that cause it

“Newborn Diet CauSeS diarrhea”

A

C. jejuni
Salmonella
Shigella

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12
Q

Mechanism of action for isoxazolyl

“Supports MSsa & Reduces MRsa”

A

active against MSSA
but
inactive against MRSA

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13
Q

Mechanism of action of ciprofloxacin
“Can I Dick Girls Today?”

A

It inhibits DNA gyrase and topoisomerase IV
&
its used for:
- gram-negative bacilli that cause (Gi and urinary tract infections
- Some gram-positive pathogens
- N. gonorrhea
- Chlamydia trachomatic
- Ureaplasma urealyticum
- Pseudomonas aruginosa

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14
Q

Mech of action of Clindamycin
“CLIP’s from The 50’s”

A

it binds the 50s subunit of the bacterial ribosome and prevents peptide translocation thereby blocking elongation and bacteria protein synthesis

Used for
c. perfringes
Bacteroides
strep. a pyogenes

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15
Q

Borrelia
B. recurrentis
B. duttoni
B. hermsii

Cause what?

“BaRF OnTo Every Desk”

B. Burgdorferi

causes what?

pathogenesis

Tests

Treat

Co-infections

“BURGers In LighT BARbacue sauceD”

A

Relapsing fever via ornithodorus tick bites (rodent born)

Look for IP 14 days fever, headache, myalgia, arthralgias, photophobia

Sometimes has hypotension and shock, which are fatal

B. burgdorferi

causes Lyme disease via ixodid ticks

Patho=
Stage1: gradual spreading rash + sometimes a bull’s eye (rash =erythema migrans)
Stage2: dissemination into the blood (weeks/months later) multiple skin lesions, neurological symptoms (cranial neuritis/meningitis), cardiac symptoms )myocardial, AV block)
Stage 3: post-infection (months/years later) monoarthritis in the knees

Tests=
- ELISA (1st test)
- Western blot (confirmatory test)
- Barbour Stoenner-kelly medium
- PCR (to detect borrelia antigens in the joint fluid)

Treat= doxycycline or ceftriaxone via IV if symptoms reoccur

Co-infections
- Babesiosis (severe in asplenic patients)
- Human granulocytic anoplasmosis

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16
Q

R. Rickettsia

causes what?

Niche

VF

Test

Treatment

A

Causes= Rocky Mountain fever (fever, severe headache, chills, aches, nausea and then 2-6 days later a developing maculopapular rash (1st on palms and soles then the chest)

Niche= ticks that bite rodents or dogs

VF= Induced phagocytosis & recruit actin for intracellular spreading

Test=
- Giemsa stain or direct immuno fluorescent antibody test
-Serology weil-felic reaction (r.rickettsia reacts with p. vulgaris OX2,19)

Treat= chloramphenicol or tetracycline

if untreated it invades the blood and causes death

17
Q

Leptospira interrogans

Niche?

Features:

Causes what?

Tests?

Treat

A

Niche= rat pee

Feat= spirochete with hook-shaped ends

Causes=
Mild (anicteric) Leptospirosis = fever, myalgia, headaches, conjunctival hemorrhages, rash, photophobia, diarrhea + vomiting
&
Severe Leptospirosis (Weil disease) = Fever, hepatitis (jaundice/acute liver failure), nephritis, anemia, high risk of hemorrhaging, & cardia issues (myocarditis, arrhythmia, pericarditis etc.)

Test= microscopy

Treat= benzyl penicillin (or doxycycline incase of allergy)

18
Q

Coxiella burnetii

Niche?

Causes what?

Test

Feature

Treat
“COws BRinG us DQ”

A

Niche Sheep, goats, and cattle (inhaled via aerosols)

Causes Q fever:
Acute= 2-6 weeks post-infection, the sudden onset of fever, chills, headache, & atypical pneumonia
&
Chronic= months-years post-infection causes low-grade fever & endocarditis

Test
- Indirect fluorescent antibody test
- Giemsa stain (shows gram-negative obligate intracellular parasites)

FEAT= Resistant to lysosomal enzymes

Treat=
acute -doxycycline
chronic doxycycline + hydroxychloroquine (interferes with parasite lysosome interaction)

19
Q

Treponema pallidum

Niche

Caused what?

Pathology

Tests

Treat

“TraP Some CRiCkets in sticky BanDs”

A

niche= mucus membranes (mouth/genitals)

Causes= Syphilis

Patho=

  • Primary stage: painless chancre on the genitals (resolves spontaneously at 3-6 weeks)
  • Secondary stage: Disseminated progression (moves into the blood) Pleomorphic-maculopapular rash (on the palms/soles which spread) & condylomata (painless wart-like lesion white-ish
  • Latent stage: No symptoms, but serology is positive for syphilis
  • Tertiary stage (some patients progress): causes
    —> Cardiovascular syphilis (~10yrs later, the treponema causes chronic inflammation of aortic vessels supplying the heart, causing necrosis and ultimately aortic dissection/aortic aneurysm)
    ANTIBIOTICS DON’T WORK FOR THIS VARIANT
      ---> Gumma (chronic, very destructive granulomatous lesions with a necrotic center that ulcerate (skin/bones) (fucks up the face pretty badly)

Others include neuro and congenital syphilis (not covered in B2 … hopefully)

Tests=
- Grows super slow (months to years for progression)
- Darkfield Direct microscopy of chancre discharge
- serological tests (non & specific tests for antibodies)
- immunofluorescence
- Treponema hemagglutination assay

Treat= benzathine penicillin, or if allergic, use doxycycline (only the primary/secondary stage)

20
Q

When treating a patient with syphilis (treponema palladium), what adverse reaction might occur?
“JuSTin Picked Selener”

A

Jarisch-Herheimer reaction

Pathogenesis= happens after being treated with penicillin because of the bacterial endotoxins released after antibiotic therapy

Its SELF-LIMITING (fever, chills, myalgia, headache)

Note it they develop hypertension or tachycardia they risk death

21
Q

Clostridium perfringes (Non enteric infection)

Gram’s report

Causes what?

Pathology

Tests

Treatment

Predispositions

“No GoodS when CamPinG ArouNd GaS PrOpane fires”

A

Gram-negative, obligate anaerobe, spore-forming double zone of hemolysis (boxcar-shaped) bacilli

Causes: Gas gangrene (aka clostridial myonecrosis)

Pathology:
1. C.perfringes infiltrates a wound & multiplies (anaerobic conditions).

  1. It secretes exotoxins i.e alpha-toxin (phospholipase lecithinase), to degrade phospholipids in the tissue causing myonecrosis, inhibiting leukocytes and making gas (seen via CT)
  2. the gas spreads to healthy tissue to colonize and fuck shit up

Early symptoms= sudden onset of SEVERE/UNRELENTING pain, followed by edema and tenderness

Later symtoms=
- massive edema with discolouration (bronze–> red-purple —> black) & bullae
- Serosanguinous discharge is usually dark and stinky
- crepitus (cracking skin from the gas)

Systemic toxicity symptoms (uh oh, double fuck)
- early (fever + tachycardia)
- late (shock + multiorgan failure) dead

Tests=
- Blood agar (double-zone/target hemolysis inner =Beta)
- Nagier’s reaction (positive = alpha-toxin)
- Robertson’s cooked meat medium (pink =acid saccharolytic & black = necrotic)
- Litmus milk fermentation (positive shows red colonies)

Treat= surgery (usually amputation), penicillin G, & a hyperbaric O2 chamber

Predispositions= ischemic vascular disease or peripheral arteriosclerosis

22
Q

Clostridium perfringes (Enteric infection)

Causes

Pathology

Tests

Complications & treatment & predispositions

“CamPing in Dirt is Wet And Problematic, I Prefer SoftNess”

A

Causes= Food poisoning

Patho= c. perfringes type A release enterotoxin (heat resistant toxins) which become pre-formed in food (SELF-LIMITING), causing abdominal pain and watery diarrhea within 24hrs of eating

Tests= stool cultures

Complication= Clostridial necrotizing enteritis (affects the small intestine via the beta toxin (from type C c.perfringes) to cause severe abdominal pain, vomiting, and bloody stool

Treat= Piperacillin, tetracycline, & clindamycin

Predispositions=
- protein-calorie deficiency
- starchy diet (lots of sweet potatoes)
- nematode infection

23
Q

Campylobacter jejuni

Gram stain

Growth conditions/transmission

Causes what?

Complications

Test

Treat

“NO Good CaJun Dishes aRe RouGh on Every Person’s tummy”

A

Gram-negative, oxidase-positive, microaerophilic polar flagellated bacilli

Grows at 37-42 degrees Celsius & transmitted via the fecal-oral route

Causes= Gastroenteritis (IP~3 days with watery/bloody diarrhea, fever, & abdominal cramps)

Complations=
- Guillain-Barre synd (ascending flaccid paralysis)
- Reactive arthritis (arthritis, conjunctivitis, & urethritis)
- Reiter’s syndrome

Test= Presence of pus cells (sensitive to nalidixic acid)

Treat= Erythromycin or ciprofloxacin

24
Q

Clostridium difficile

Gram’s report

Niche

Causes what?

Pathology

VF

Test

Treat

“Positively GoodS APles Picked At Breakfast Mmmm!”

A

Gram-positive, obligate anaerobe, spore-forming, bacilli

Niche= Gi tract

Causes= Antibiotic-Associated diarrhea + pseudomembranous colitis (watery diarrhea, cramping/pain, abdominal tenderness, fever)

Patho=
—> When a patient is treated with a large dose of antibiotics (esp clindamycin), it wipes out most gut flora, but the resistant c. difficile can take over
—> 1st response is short/sluggish, allowing c.difficile to multiple
—> 2nd response (anamnestic) is prompt/powerful/prolonged with IgG’s against the toxin A leading to pseudomembranous colitis

VF= Toxin A (enterotoxin= diarrhea) & Toxin B (cytotoxin = pore forming)

Test= Stool toxin test (PCR + Enzyme immuno assay to detect toxins)

Treat=
- Metronidazole
- oral vancomycin
- fidaxomicin

25
Q

Haemophilus influenza

niche

Gram’s report

Test

VF

Causes

Treat

Prevent

“No Good Can Be HIdden In COPs But SENd it”

A

niche= nasopharynx

Gram-negative cocobacilli

Test= chocolate agar (forms double zone/target hemolysis due to available factors X (heme) & V (NAD) grows well with s. aureus because of this)

VF= capsule (polymer of ribitol phosphate) & IgA protease

Causes=
- Un- encapsulated strain: Exacerbates COPD, Ostitis media, sinusitis, & pneumonia
&
- Type B strain (capsulated + more severe): neonatal Meningitis (K1 antigen), epiglottitis, septic arthritis (asplenic), & bacteremia)

Treat=
- For meningitis, use cefotaxime or ceftriaxone
- For everything else, use amoxicillin-clavulanate or cefuroxime

Prevent=
- Hib vaccine (active immunity via a purified type B capsular polysaccharide + DTap booster
&
Chemoprophylaxis = rifampicin (NOT PREGGOS)

26
Q

Ecoli

Gram’s report

Niche

Causes

Tests

VF

Subtypes

A

gram-negative, facultative anaerobic bacilli

Niche= gut, fecal matter, & water

Causes: UTI, neonatal meningitis, neonatal septicemia, & diarrhea

Serotypes= “O” Somatic, “H” Flagellar, “K” capsular

VF= P fimbriae (these bind to P blood group antigens causing a risk for UTIs in CGD patients

Subtypes:
- EPEC (enteropathogenic) = infantile diarrhea, usually SELF-LIMITING, causing a loss of microvilli; NOTE breastfeeding is protective

  • ETEC (enterotoxigenic) = travellers diarrhea (rapid onset with nausea, vomiting, & abdominal pain. Treat with rehydration & ciprofloxacin

EIEC (enteroInvasive) = causes bacillary dysentery (mucopurulent + bloody poop) & fever, abdominal pain and tenesmus (frequent urge to pee)

VTEC/EHEC O157:H7 BEEF (vero-cytotoxin/enterohemorrhagic) = causes hemorrhagic colitis (very bloody diarrhea) and hemolytic uremic syndrome (thrombocytopenia, acute kidney injury, anemia from occluded blood vessels)

Test= pale colonies on sorbito MacConkeys agar

Treat=
- neonatal meningitis= cefotaxime
- local/systemic disease= Ampicillin, cefotaxime, aminoglycoside, ciprofloxacin, trimethoprim/sulfamethoxazole
- UTI= Ciprofloxacin/trimethoprim/sulfamethoxazole

27
Q

Shigellae dysenteriae

Gram’s report

Causes

Pathology

VF

Tests

Treatment

A

Gram-negative, facultative anaerobic, bacilli

Causes=
- shigellosis (bacillary dysentery): mucoid/bloody diarrhea, abdominal cramps, high fever & tenesmus (urge to pee)
- hemolytic uremia syndrome (hemolytic anemia, thrombocytopenia, acute renal failure)

Path= ingesting a small dose –> bacteria multiply in the large intestine & enter the gut epithelia
—> they multiply again and spread into the lamina propria to slough off epithelia, causing inflammation and polymorph invasion (dysentery)

VF= shigatoxin (exo+endo toxin)

Tests=
- Pale on MacConkey’s (no H2S or lactose fermentation)
- Pus cells

Treat=
-SELF LIMITING & rehydrate
- only use antibiotics if –> the infection’s severe, a very young child or the patient is elderly /or/ has AIDS
(Ampicillin, cotrimoxazole, or ciprofloxacin)

28
Q

Salmonella typhi

Niche

Gram’s

Causes

Pathology

VF

Tests

Treatment

A

Niche: gut risk from undercooked chicken/eggs

Gram-negative, catalase positive, glucose fermenting motile bacilli

Causes=
- Typhoid fever (Rose spots on the trunk/belly, fever, chills, abdomenopathy)
- Osteomyelitis ( especially sickle cell patients

Patho (typhoid):
Ingest a large dose of s. typhi, which migrate to the Peyers patch via M cells through the epithelium —> in they Peyers patch they infect macrophages and spread into the blood, causing septicemia + systemic disease

VF= flagella, Vi capsules (evade neutrophils), & endotoxin (polysaccharide + lipid A induce a cytokine storm IL1,6 & TNFa causing septic shock and clots)

Tests=
- Gastric acid sensitive
- Kaufman + whites ID (“O” antigen (9,12) phase 1 (d) phase 2 (-))

Treat=
-1st fluoroquinolones (ciprofloxacin)
- Or 3rd gen cephalosporins (ceftriaxone) for severe infection

Prevent=
- live attenuated vaccines (parental inactivated vaccine(Vi polysaccharide IM) & live oral vaccine = active immunization

29
Q

Eating undercooked beef can cause food poisoning via

A

E.coli (VTEC/EHEC) O157:H7

30
Q

Eating runny eats can cause food poisoning via

A

Salmonella

31
Q

Eating canned food can cause food poisoning via

A

Clostridium botulism

32
Q

Eating raw pork can cause food poisoning via

A

yersinia entercolitica

33
Q

Eating raw shellfish can cause food poisoning via

A

Vibrio vulnificus & Vibrio parahaemolyticus

34
Q

Eating reheated rice can cause food poisoning via

A

Bacillus cereus

35
Q

Bordetella pertussis

Grams

Causes

Pathology

VF

Tests

Treatment

A

Gram-negative strictly aerobic coccobacilli

Causes= Whooping cough (100-day cough)

Patho:
- Catarrhal Stage (very contagious with cough, rhinitis, sneezing, & a low-grade fever)
- Paroxysmal whooping Stage ( Severe paroxysmal cough & inspiratory whoop that leads to hypoxia, cyanosis, protruding tongue, eyes, and veins. Note patient is a very high vomit risk)
- Convalescent stage (the recovery period where the patient is not infectious, but some can still develop superinfections leading to pneumonia and death)

VF=
- Tracheal cytotoxin (destroys cilia to reduce clearance capacity)
- Filamentous hemagglutination (improves attachment to mucus membranes)
- Pertussis toxin (AB subunits B (Binding) & A (active cleave and does ADP-ribosylation to inhibit Gi –> activated AC –> more cAMP–> PKA which inhibits lymphocytes & phagocytes))

Tests= Grow in a Bordet-Gnegou or charcoal yeast extract

Treat = Erythromycin (4 days). Side effects are GI irritation and pyloric stenosis in infants. An alternative is Azithromycin or ampicillin

36
Q

Bacillus cereus

Grams

Niche

Causes

Pathology

VF

Tests

Treat

A

Gram-positive, aerobic, spore-forming, intracellular bacilli

Niche= Reheated rice/overnight rice

Causes= Food poisoning within 24hrs

Pathology=
- Spores survive the cooking process and germinate when the rice is reheated rice to pre-form their enterotoxin (cereulide), which is then ingested when the rice is eaten

Emetic form = Enterotoxin 1 (causes nausea and vomiting 30mins-to-6hrs post-ingestion)

Diarrheal form= Enterotoxin 2 (causes watering diarrhea and abdominal pain 6-15hrs post ingestion it usually lasts around 24hrs

VF= Cereulide (enterotoxin)

Tests= Blood agar shows anthracoid colonies (10^8 is significant)

Treat= SELF-LIMITING only rehydrate unless it’s severe use vancomycin or clindamycin & an aminoglycoside

37
Q

Aeromonas hydrophila

Niche

Cause

Test

Treat

A

Niche= water

Causes=
- gastroenteritis (seafood/oysters) SELF-LIMITING
- cellulitis + necrotizing fasciitis (water-related wounds)
- myonecrosis + eczema in AIDs patients
- Septicemia

Test=
- Sheep blood agar (shows beta hemolysis)
- MacConkey’s (shows pink lactose fermenting colonies)
- Oxidase positive & Indole negative
- Selective media CIN (show pink centred colonies)
- O129 differential disc = Resistant

38
Q

Corynebacterium diphtheria

Grams

Niche

Causes

VF

Tests

Treat

A

Gram-positive, facultative aerobe (club-shaped) bacilli in angular arrangements (Chinese lettering)

Niche= Respiratory tract

Causes=
Diptheria (fever, sore throat with a gray-white pseudomembrane (scraping causes bleeding, bull-neck (cervical lymphadenopathy))
&
If toxin disseminates (enters the blood) = myocarditis, arrhythmias, & reversible polyneuropathy

VF=
- Diptheria toxin (exotoxin) that inactivates eF2 to inhibit protein synthesis
- Fibrinous exudate (a gray-white pseudomembrane covering the back of the throat)

Tests=
- Neisser + Albert’s stains show metachromatic granules (red + blue)
- Elek test is positive for the diphtheria toxin
- Loeffler medium shows fast growth and metachromatic granules
- Selective media is the Cysteine-tellurite agar which shows black colonies

Treat= penicillin G + Diptheria antitoxin (alternatives = macrolide and erythromycin)

Microbiology SJSM (12 decks)

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