Sketchy Micro: Bacteria

Staphylococcus aureus

Gram positive cocci (grape-like, gold in color - the golden staph of Moses)

- Gram positive (Moses robe is purple)

- Catalse + (cat -> converts H2O2->H2O)

- Coagulase + (Parting the red sea -> changes fibrin to fibrinogen = clotting factor)

Beta hemolytic (bright red B lightbulb)

What lysing pattern does S. Aureus have?

yellow (+) = tall man in yellow vest

What color does S. aureus turn a mannitol salt agar?

Protein A (A on Moses's staph): binds FC region of AB prevent complement, opsonization and phagocytosis

What is the main virulence factor of S. Aureus?

S. Aureus (bandages on camels knees)

What is the most common cause of septic arthritis in adults?

S. aureus infects the tricuspid valve usually is very rapid (camel running fast, women clutching heart with drug mortar and pestel in front of three pyramids)

What valve/organism is usually involved when an IV drug user gets bacterial endocarditis?

S. Aureus -> non-specific binding of MHC to T cell causing a cytokine storm (man with scalded head wearing a TSS lightening bolt cape)

What causes TSS and scalded skin syndrome?

Vancomycin (caravan) or Nafcillin in MRSA (naf for staph)

What do you use to treat S. Aureus?

Staphylococcus Epidermidis/saprophyticus

(violet color, cat, ammonia bottle, non-coagulase jello) both in normal skin flora (dirt on plumbers arms)

Gram positive cocci, catalase positive, urease positive, coagulase negative is what?

infects hardware (orthopedic joints, heart valves), catheters (tubing) via biofilms (gung on pipes)

How does S. epidermidis cause infection?

- Vancomycin (van) or removal of the prosthetic hardware

- Novobiocin sensitive (naval of plumber showing)

What is the treatment of S. Epidermidis?

Staphylococcus saprophyticus

(young lady on counter drinking a bladder shaped drink, no belly button showing = novobiocin resistant)

What is the most common cause of UTI in sexually active young females?

Streptococcus pyogenes (The pie genies bakery)

What is group A strep called?

hyaluronic acid (hot apple pie in glass covering with beta hemolytic lamp over it)

What makes up S. Pyogene's capsule, and lysis pattern?

- Impetigo (honey crusted pie)

- Erysipelas (cellulitis with well demarcated borders) - red mittens holding impetigo pie)

- Strep throat (pharyngitis - red scarf around neck of baker)

What skin lesions does S. Pyogenes cause?

called streptococcal pyrogenic exotoxin (SPE)

- Scarlet Fever (strawberry tongue, red scarf for pharyngitis, and wide spread rash that spares the face (gingerbread man with no red frosting on face)

- Toxic shock like syndrome (Cape with bolt) via super antigen (SPE A, SPE C)

- Necrotizing fasciitis (burnt gingerbread man, B = SPE B) "flesh eating bacteria" requiring amputation

What three issues does Strep toxin cause?

in GAS = main virulence factor for Rheumatic fever (Master chef wearing a miter hat = mitral valve)

- interferes with opsonization, antiphagocytic, mimic heart myosin (molecular mimicry)

- Can only come from pharyngitis, not impetigo (chef wearing red scarf)

What is a M protein?

J: Joints (polyarthritis)

O: "heart" problems (mitral valve stenosis)

N: Nodules on extensor surfaces (arms, elbows, knees)

E: Erythema marginatum

S: Sydenham's Chorea (milk maid grip)

"JONES cupcakes"“

What does the JONES criteria stand for?

allows strep to be beta hemolytic (we form Anti-Streptolsin O AB -> check titers for active infection or in the case of PSGN/RF)

Why is Stretolysin O relevant?

Virulence factor of GAS that phosphorylates plasminogen to Plasmin (used to lyse clots in MI)

What is streptokinase?

GAS (basset hound licking cupcakes)

What is bacitracin sensitive?

Stretococcus Agalactiae (galactic baby)

purple: gram +

Beta lamps = beta hemolytic

basset hound with capsule = bacitracin resistant

Gram positive cocci, beta hemolytic, bacitracin resistant

GBS (Group B Strep = Strep. Agalactiae)

- galactic baby in helmet coughing wearing a septic red next to tunnel (vagina)

- culture mom at 35 weeks and give intrapartum penicillin if + (stabbing pencils into the mothership with 35 writing on it)

What is a major cause of pneumonia, meningitis, sepsis infection of newborns received in the vaginal canal?

S. agalactiae (hydrolyzes sodium hippurate - hippo doll with head capsule) and CAMP tent

What bacteria is hippurate test +, and CAMP +?

Streptococcus Pneumonia (the alpha knight tournament)

- purple background (gram +)

- Knight in armor (capsule = major virulence factor), with his chin exposed (optichin sen)

- double lance sword (diplococci)

- mud on horses legs (doesn't grow in bile)

Gram positive lancet diplococci, alpha hemolytic, with polysaccharide capsule, optichin sensitive, bile soluble

Strep Pneumonia

- rust colored single lobe on chest (rust colored, lobar pneumonia)

What is the most common community acquired pneumonia?

Strep Pneumonia

- MOPS (squire mopping up muddy mess), with number 1 sign

What is the number 1 cause of meningitis, otitis media, pneumonia, and sinusitis?

Proteases that cleave IgA - allow invasion of mucosa

How does Strep Pneumonia invade hosts?

Encapsulated bacteria (strep pneumonia, haemophilus influenzae, Neisseria Meningitidis, salmonella typhi)

What are sickle cell patients with splenectomy most at risk for?

Adults: 23 valiant polysaccharide (IgM response that doesn't last long)

Children: 7 valent conjugated (diptheria toxin) to increase AB response (IgG) longer lasting

"Adults in the Mezzanine, Children on the Ground"

What are the two different pneumococcal vaccines?

Strep. Veridians

- Jester in no armor, face mask over whole face including chin, donkey with bile resistant boots

Gram positive, alpha hemolytic, non-encapsulated, optochin resistent, bile resistant?

Dental caries -> most common cause for acute bacterial endocarditis

- deck of cards with plate shield = Makes dextran from glucose -> allows it to bind to fibrin from platelets in damaged heart (enter via dental surgery)

What is Strep viridians associated with?

strep sanguineous

What is a common cause of mitral valve endocarditis?

Enterococcus (intestinal/round)

E. Faecalis (many people under the California caucus sign = more common)

Buff protester ("stop the fees") = E. Faecium is more dangerous

"resist the 6.5% N.Ca" = can grow in NaCl

bile resistnat boots

Gram positive cocci, bile resistant, 6.5% sodium growth?

UTI, Endocarditis, biliary tree infection

"Do U Heart Trees"

What does Enterococcus cause?

Nosocomial and resistant to vancomycin (not going in van)

- Give Linezolid (police "LINE") and Tigacycline (tiger stripes on police line)

What can you use to treat E. Faecium

Neisseria "Noir series"

- red theme (gram -)

- double handcuff (diplococci)

- blue ring (oxidase positive)

- holding chocolate agar

Gram negative diplococci, oxidase positive, grows on chocolate agar

enriched with vancomycin, polymixin, nystatin to kill off many organisms except Neisseria

"Vice city Private Nvestigator"

starring THAYER MARTIN = VPN agar (selective agar)

what is VPN agar?

it inhibits C5-9 and prevents formation of the MAC (membrane attack complex)

- Thayer Martin as "MAC" the private eye

- Airs 5-9pm

How does Neisseria prevent its own attack?

1. antigenic variation pili allows movement to surfaces

2. IgA protease will cleave IgA at its hinge point = survival along mucosal surfaces

- different pocket watch chain metals

- Ace with IgA symbol in MAC's hat

What are Neisseria's virulence factors?

in areas of close contact (college dorms, military recruits) via respiratory droplets (kissing, sharing drinks etc)

hence why this scene takes place in a college dorm "a Shocking death on campus"

Where is Neisseria meningitides usually contracted?

Meningitides ferments maltose/glucose

- MALT liquor in MACs hand

- found in nasal cavity (nasopharyngeal swab on the MALT bottle)

What differentiates Neisseria Meningitides vs. gonorrhea and where is it found?

A, C, D polysaccharide capsules not B hence why most infections are type B

- Syringes on the floor covered by capsules, B has no syringe in the capsule. capsule evades phagocytosis = major virulence factor

Which strains of Neisseria Meningitides do we have vaccines against?

those with sickle cell disease (sickle and hammer flag) as it is encapsulated

What population is more susceptible to Neisseria meningitides?

massive inflammatory response to LOS (lipooligiosaccharides) (burning envelopes) followed by leakage of interstitial fluid by capillaries -> hypovolemia (sprinklers going off on top landing on outlet = SHOCK)

What is the toxin/response to Neisseria meningitides?

characteristic petechial rash (spots on boxers and carpet)

What dermatological sequela occur with Neisseria meningitides?

Severe shock from Neisseria meningitides -> thrombocytopenia -> DIC (disseminated intravascular coagulation: bleeding gums, oozing at puncture sites)-> severe vasoconstriction = adrenal infarctions that will worsen shock (15% fatality)

waterhouse visualized through the window

What is waterhouse-fritter syndrome?

ceftriaxone (3rd generation cephalosporine) as this can penetrate BBB

- three axes on the firefighter

How do you treat Neisseria Meningitides?

rifampin (police holding off family members at door holding rifle)

How would you treat someone in close contact (spends more than 8 hrs w/ patient during 7 days prior to onset)?

"Gonzo's" = gonorrhea (The violinists last clap)

- Gram negative (red) diplococci (two red pillows on chair)

- facultative intracellular and invade PMN (polymorphonuclear lymphocytes - white round chairs)

NOT encapsulated: glass falling off table and breaking

thick purulent discharge on table from dripping wax from uterine lamp

What kind of bacteria is Neisseria gonorrhea?

Fitz Hugh Curtis (Note the Fitz Hugh Curtis Band) -> violin string like adhesions in liver from PID spread to peritoneum

What is a sequela of PID cause by gonorrhea in a female?

polyarthritis that is asymmetric (knight falling and breaking his knees)

What is another sequela of Neisseria gonorrhea?

conjunctivitis within 5 days of birth (mother QUICKLY shielding baby's eyes) opposed to chlamydia that is a slow developing conjunctivitis

What can a neonate get from a mother with gonorrhea?

ceftriaxone (three axis on the wall) but will also treat for assumed co-infection with chlamydia (azithromycin) hence why there are clam shells on the table

How do you treat gonorrhea?

Bacillus cereus (aerobic and spore forming)

- viking vomiting, heated rice (usually from reheating a starch -> re-activates spores leading to diarrhea)

What illness do you get from eating re-heated rice?

Clostridium tetani

"Rhesus research revolution"

gram positive bacilli

-obligate anaerobes (gas masks)

- Spore forming (walnuts)

rusty nails, barbed wire, pots of soil indicate they are found in dirt and usually enters body through a puncture wound (stab wounds, construction zones etc)

How is clostridium tetani transmitted?

1. Trismus (lockjaw) involves spasms of the jaw muscle and clenching of the teeth

- Rhesus sardonicus (to grin, evil - monkey grinning)

2. Opisthotonus: powerful muscle spasms that cause an arching of the back (monkey arching back)

3. Spasmodic inhalation and seizures in the diaphragm and rib cage reduce ventilation.

What are symptoms of tetanus?

Puncture wound with item that has spores on it -> spores stay at wound site embedded in flesh -> toxin travels retrograde through motor axons -> spinal cord (monkey pulling scissor toxins up from bottom to top)

How does tetanus enter the body?

Attacks Renshaw cells and cleaves snare and inhibit exocytosis of NT GABA and glycine into synapse (inhibiting inhibitors -> spastic paralysis)

-Monkey cutting SNARE trap with G&G worker

What does tetanus toxin do?

Renshaw cells

Inhibitory Interneurons that coordinate complex motor activities -> target of tetanus (monkey holding a wrench and a saw)

- They monitor firing from motor cells and work to prevent hyperactivity (in tetanus without this = hyperactivity)

it is a toxoid vaccine (conjugated) and AB responds to the toxin, NOT to the organism

What is the vaccine available for tetanus?

"robotulism"

- gram positive bacilli (rods) (purple hues)

- spore formers (nuts -> like tool nuts)

- obligate anaerobes (gas mask)

Describe Clostridium botulinum

improper canning of food allows TOXIN to flourish in anaerobic environment and produce heat stable toxin (hence why you should cook canned foods)

- robots made of cans

How is Clostridium botulinum transmitted?

flaccid paralysis (no muscle contraction), descending paralysis (opposite of Guillen Barre ascending paralysis). Especially a whole family coming in sick, or those returning from a camping trip (eating out fo cans)

- Early symptoms: ptosis and diplopia

- toxin can't cross BBB: only symptoms in PNS (gut->blood->PNS)

-Robots with drooping heads, eyes are closing

What are the symptoms of botulinum poisoning?

Toxin is a protease that cleaves SNARE protein -> blocks acetylcholine release (prevents exocytosis vesicles from docking to the membrane to release the Ach) and

results in paralysis (botox or botulism infection)

- Guy in gas mask cutting Ach wires with SNARE scissors

How does Clostridium botulinum work?

Reduced muscle tone (hypotonia) from botulinum poisoning

floppy robot baby over honey

What is floppy baby syndrome?

clostridium botulinum SPORES (not toxins) exist in 12% of honey. Babies don't have robust flora of gut and can't outcompete the bacteria. Once ingested the spores release toxin

Why can babies not eat honey?

Clostridium defficile

"field trip to the chocolate factory"

most hospitalized patients have it, but are not symptomatic

- Spore forming (walnuts)

- gram positive bacilli (purple hats/masks)

- obligate anaerobe (gas masks on workers)

- Poorly washed hands (spores are easily transferred, must use soap and water - not just alcohol -> nosocomial diarrhea)

- Antibiotics (clindamycin) wipe out normal gut flora allowing toxin formation

- Sign that says "CLEAN your hands" for clindamycin

What causes c. diff infections?

1) Exotoxin A: binds to the brush border in the intestines -> inflammation, cell death, watery diarrhea (A is for apples being brushed with chocolate)

2) Exotoxin B: disrupts cytoskeleton by depolymerizing actin -> enterocyte death and necrosis (B=black licorice looks like actin being chewed up by a little kid on the ground)

What are the two toxins formed by Clostridium Defficile?

yellow grey exudate forming a pseudomembrane covering colonic mucosa = pseudomembranous colitis

- worker packing black licorice in sheets of yellow wrapping

What is a would be seen in a colonic infection of c. diff?

assay to detect toxin in stool via PCR

- kid sitting upstream of the chocolate fountain and worker finding his shoe downstream

How do you test for c. diff?

- Oral vancomycin (don't use iV as we want to deliver max dose of AB directly to location of infection - van unloading in the back of the factory with a tongue sticking out)

- Metronidazole (metro train coming through factory)

How do you treat C. diff?

Clostridium Perfringes

"Private Ringen's motorcycle accident"

- spore forming (walnuts)

- gram positive bacilli (rod - purple awning)

- obligate anaerobe (gas mask)

- causes double zone of hemolysis on agar (rare for anaerobe, "double fine zone" on red sign)

accidents/deep wounds with large amounts of flesh exposed to dirt/soil where spores are

- Private Ringens has cuts on his knees after motorcycle accident with spilled over pots of soil

How is Clostridium perfringens transmitted?

Gas gangrene: after entering wounds it can cause clostridial myonecrosis, and produce gas under the tissue -> cracking sound on palpation (gas made as bacteria consumes carbohydrates)

- Gas leaking out of motorcycle

Food poisoning: from spore ingestion (late onset)

What are the effects of Clostridium perfringes infection?

Alpha toxin: this is a lecithinase (phopholipase) that effects lipid bilayer/cell membranes and lyses RBC (hemolysis) -> myonecrosis

- Alpha flag hung up with lipid membrane like proteins falling off, with red tomatoes smashed on the ground

What is the toxin of Clostridium perfringens

SLOW: spores need time to reproduce in gut and create toxin -> transient diarrhea that doesn't need treatment

- Slow sign falling over into spilled "motorcycle oil" that looks like diarrhea

What is the temporal onset of diarrhea in clostridium perfringes?

IV penicillin G

- woman in tomato stand holding a pencil

What is the treatment for C. diff?

Corynebacterium diphtheriae

"Corazon de la Corrida" (heart of the bull fight

- gram positive bacilli (purple ring)

- non-spore forming

- club shaped, Y or V shaped with metachromatic granules that stain with aniline dyes (granules will stain red and rest of cell will stain blue - moroccos that are red/blue with zig zag shapes

2 subunits (A active, B binding)

- toxin causes ribosylation of elongation factor 2 -> inhibits ribosome function -> inhibits protein synthesis -> cell death

- accordion player (elongating instrument) wearing green (toxin) bow tie

What does the corynebacterium diphtheria toxin do?

thick grey exudate in the oral pharynx (psuedomembranous exudate)

- children eating grey cotton candy covered in a green membrane wrapping

What does corynebacterium diphtheria in the pharynx?

found in the throat and tonsils as it spreads via respiratory droplets -> airway obstruction/lymphadenopathy -> bulls neck (thickening of the neck)

- Usually in immigrants (hence why sketchy was in diff language (no vaccines)

- bull spitting with tongue out and large neck

How is diphtheria transmitted?

- Myocarditis like arrhythmia and heart block (lethal effect of infection)

- Neuropathy: will damage myelin nerve fibers and cause local paralysis (beginning in the posterior pharynx -> other CNS deficits)

- cape with bull in the shape of a heart

- man eating sausage links to look like myelinated cells

What are two non-pharyngeal effects of diphtheria?

- plate swab on Tellurite and Loeflers media (kid watching television and laughing and enjoying the show)

- Eleks test: in vitro assay with antitoxin on it (bull sticking tongue out to like matador)

How do you diagnose Diphtheria?

toxoid vaccine given with tetanus and pertussis (DTaP) to elicit a powerful IgG response

- Syringes on bull

What is the vaccine for Diphtheria?

give passive immunization via anti-toxoid

What is the treatment for Diphtheria?

Listeria monocytogenes

"santa's list"

- gram positive bacillis (rod - purple oblong ornaments)

- beta hemolytic (beta lamp on top of tree)

- Catalase positive (cat)

motile and facultative intracellular bacteria

- Extracellularly: moves with "tumbling motility" and uses flagella (tumbling ornaments coming off tree)

- Intracellularly: it rapidly polymerizes actin along the cell wall allowing it to move quickly (called an Actin rocket = rocket in santa's bag/cell) this is how it jumps from cell to cell

How does Listeria move?

In near freezing temperatures (icicles on window)

In what environment does listeria multiple?

contaminates food items (even if they are refrigerated) like unpasteurized milk/dairy

- cheese left out for santa

How do you get listeria?

pregnant women (20x as likely, shouldn't eat soft cheeses) -> may lead to termination or meningitis in a newborn (third most common cause in newborns ((first = GBS, then E. coli) and in elderly)

- pregnant mom, baby on floor with space meningitis helmet

What population is most at risk for listeria?

Ampicillin (amp under the tree with guitar) for just listeriosis

- for elderly (>60) with meningitis: ampicillin, vancomycin, and ceftriaxone

How do you treat listeria? What about meningitis from listeria in the elderly?

Proteus Mirabilis

" The god of the public restroom"

- gram negative enteric bacilli (red hue)

- swarming motility when plated (swarming tentacles)

- faculative anaerobe

- urease positive (ammonia spray)

- H2S positive

Proteus mirabilis

- urease positive bacteria that makes an alkaline environment turns stag horn calculi -> struvite stones made of ammonia, magnesium, and phosphate (painful, kidney damage, recurrent infection)

- staghorn helmet while he is throwing a stone

What causes staghorn calculi in the kidney?

Struvite kidney stones and UTIs with fishy odor

- fish on floor, and man peeing in bathroom

What can Proteus Mirabilis cause?

Sulfonamides

- smelly eggs on floor

How do you treat Proteus Mirabilis?

Yersinia enterocolitica / pestis

" Yersins Pets"

- gram negative enteric bacilli (red hue)

"English terrier"

- transmitted through puppy feces most commonly effecting children

- contaminated milk products

- poopy puppy licking baby on stool holding milk

How is Yersinia enterocolitica transmitted?