microbio quiz 3: yeast and UTI

candida albicans morphology

IMA: white, pasty, and convex

chromagar: mottled green
BA: feet

cornmeal: chlamydospores

candida albicans clinical

most common cause of serious fungal disease

candida albicans and dubliniensis biochem

cycloheximide tolerant, germ tube pos

candida dubliniensis morphology

IMA: white, pasty, and convex
chromagar: dark solid green
cornmeal: clusters of chlamydospores

candida dubliniensis clinical

candida associated with recurrent oral candidiasis in HIV patients, fluconazole-susceptible isolates able to rapidly develop resistance in vitro

candida glabrata clinical

candida associated with UTIs

candida glabrata morphology

IMA: white, pasty, and convex

chromagar: pink to lavendar
cornmeal: no pseudohyphae or chlamydospores

candida glabrata and parapsilosis biochem

cycloheximide susceptible, germ tube neg

candida parapsilosis morphology

chromagar: white or pink

cornmeal: lacey like pseudohyphae

candida tropicalis morphology

chromoagar: blue

cornmeal: vigorous hyphal growth

candida tropicalis biochem

cycloheximide susceptible, germ tube neg(may be pos after 3 hrs)

candida auris clinical

candida that is the cause of serous and invasive illness, nosocomial and difficult to id, multidrug resistant, high mortality

candida auris morphology and biochem

chromagar: light blue with blue halo
cycloheximide sensitive

cryptococcus disease

acute or chronic infection, pulmonary or meningitis

cryptococcus morphology

IMA: dome shaped, shiny white/tan, may be mucoid
chromagar: scant white growth

cryptococcus biochem

cycloheximide sensitive, no pseudohyphae, caffeic acid pos, urease pos

cryptococcus neoformans

cryptococcus thats an opportunist in immunocompromised, CGB agar neg

cryptococcus gatii

cryptococcus that can infect healthy people, CGB agar positive, reportable to public health

antifungal testing

performed on all blood culture isolates and sterile sites, or by request for other sites
TREK sensitive Yeast One
CLSI breakpoints for candida only

UTI demographic

more women affected due to length of urethra, increased in male geriatric patients, diabetes mellitus

types of UTIs

pyelonephritis, cystitis, urethritis, uncomplicated, complicated

pyelonephritis

local: dysuria, flank pain, cua tenderness

systemic: high fever, chills, malaise

cystitis

local: dysuria, frequency, urgency, suprapubic pain
system: possible low grade fever

urethritis

local: dysuria, urethral discharge, irritation
systemic: usually none

uncomplicated UTI

UTI that occurs in healthy patients, lower urinary tract, resolves with treatment/outpatient, usually a single episode

complicated UTI

UTI that occurs in patients with risk factors, upper urinary tract, more difficult to treat, risk of kidney damage, bacteremia, mords

UTI virulence factors

adherence(fimbrae), motility(ascending infection), biofilm, iron uptake, toxin production, urease leading to calculus formation, capsule, cytokine evasion

ascending UTI

most common UTI caused by GN enterics or GPCs

hematogenous spread

UTI caused by bloodstream infection: s. aureus, salmonella in immunocompromised, MTB, nosocomial candida, listeria, GAS, etc.

clean catch midstream

urine collection, first void is best, preparation very important

catheters

straight: intermittent
Foley: indwelling, take sample from drainage port, never take sample from bag

pediatric urine bag

sample collection type used in pediatrics, not ideal for culture due to high contamination rate

suprapubic aspirate bag

invasive urine collection type used when other methods are not possible, suitable for anaerobic culture

nephrostomy

urine collection type that is attached to kidneys and leg, has high contamination risk

prostatic secretions

type of collection that is used to distinguish prostatitis from urethritis, cystitis, or upper UTI

collection and transport of urine

process within 2hrs or in fridge at 4C for up to 24hrs
boric acid sodium borate/formate allows for 48hr stability at room temp: boric acid inhibits bacteria and formate stabilizes urine

reflex to culture

leukocyte esterase pos
nitrite from GN enterics(false neg from enterococcus, pseudomonas, and staph sapro)
pyuria: wbc >5/hpf

media for urine culture

BA, Mac, orientation agar

invasive specimens hold for three days: CO2 on CA or ANA brucella

colony counting

.001 ml loop: 1colony = 1,000 cfu/ml

.01 ml loop: 1 colony = 100 cfu/ml

max limit: 10^5 = >100,000 cfu/ml

colony significance

significant: greater than or equal to 10^5 cfu/ml
maybe significant: greater than or equal to 10³ cfu/ml, especially women with symptoms or evidence of acute cystitis

suprapubic or straight catheter: any amount significant
UTIs rarely polymicrobial: reported mixed flora for greater than or equal to 3 potential uropathogens

urogenital flora

CoNS(except staph sapro), micrococcus, corynebacterium(except c urealyticum), viridans, lactobacillus, gardnerella vaginalis

gram neg uropathogens

enterobacteriaceae, pseudomonas aeruginosa, acinetobacter baumanii, stenotrophomonas maltphila

gram pos uropathogens

staph aureus(especially MRSA), staph sapro, staph epidermidis(geriatric, catheter), enterococcus(geriatric), beta hemolytic strep

other uropathogens

aerococcus urinae, actinotignum schaalii, alloscardovia omniocolens, neisseria gonorrhoeae, yeasts

gardnerella vaginalis

gram stain: pleomorphic gram variable rods
morphology: tiny clear pinpoints

biochem: catalase neg

lactobacillus

gram stain: long thin parallel GPR
morphology: small/med alpha hemolytic
biochem: catalase neg

staph sapro biochem

catalase pos, staphaurex neg, novobiocin resistant

micrococus

gram stain: GPC in tetrads
morphology: yellow colonies
biochem: catalase pos, coagulase neg, modified oxidase pos, bacitracin sensitive

GBS, strep agalactiae

microbiota of female genital and GI tract that can confer neonatal disease
morphology: soft beta hemolysis, whitish gray, orange
biochem: catalase neg, CAMP pos, hippurate hydrolysis pos, latex b

viridans streptococci

gram stain: GPC

morphology: alpha hemolytic, tiny
biochem: catalase neg, optochin resistant, pyrase neg

enterococcus

gram stain: GPC in chains
morphology: medium, gray, non hemolytic
biochem: catalase neg/pseudo, pyrase pos, hydrolysis of esculin in bile, growth in 6.5% NaCl

pseudomonas aeruginosa

gram stain: long slender GNR
morphology: pigment, metallic

biochem: non lactose fermenter

acinetobacter baumanii calcoaceticus complex

gram stain: large GNCB, may appear gram pos
morphology: lavendar on mac
biochem: strict aerobes that oxidize glucose, oxidase neg, non motile

stenotrophomonas maltophila

gram stain: GNR

Mac: lavender green
biochem: strict aerobes that oxidize glucose, oxidase neg, motile

ecoli

morphology: medium, gray, beta hemolytic|
biochem: lactose fermenter(A/A), indole pos

klebsiella

morphology: spready, white, mucoid
biochem: lactose fermenter(A/A), non motile, LDC pos, Indole(pos for oxy, neg for pneu)

enterobacter

morphology: dark pink on mac, flat
biochem: lactose fermenter A/A, ornithine pos, citrate pos, urea pos

neisseria gonorrheae

gram stain: GNCB
morphology: grown on CA, tan

biochem: oxidase pos, oxidizes glucose only, NET prolylaminopeptidase
must have 2 identifying tests to report