Urine CultureUrine Culture

Urine Gram StainUrine Gram Stain

Urine Culture QuantitationUrine Culture Quantitation

Clean catch or catheterized urineClean catch or catheterized urinePlate = 1000 organisms/mlPlate = 1000 organisms/ml

Clean catch: >10Clean catch: >1055 orgs/ml orgs/ml

Suprapubic urineSuprapubic urine Any colony is significiantAny colony is significiant

Urine CulturesUrine Cultures

11 . .Plates initially read at 18-24 hrPlates initially read at 18-24 hr

22 . .All specimens plated after NOON of All specimens plated after NOON of the previous day, hold another the previous day, hold another overnightovernight

33 . .Gram positives take longer to growGram positives take longer to grow

Most Common Pathogens of Most Common Pathogens of Human Urinary TractHuman Urinary Tract

Community acquiredCommunity acquired– E. coliE. coli is most frequent pathogen isolated is most frequent pathogen isolated– KlebsiellaKlebsiella sp and other Enterobacteriaceae sp and other Enterobacteriaceae– Staphylococcus saprophyticusStaphylococcus saprophyticus

Hospital acquiredHospital acquired– E. coli, Klebsiella,E. coli, Klebsiella, other other Enterobacteriaceae Enterobacteriaceae– Pseudomonas aeruginosaPseudomonas aeruginosa– Enterococci and StaphylococciEnterococci and Staphylococci

Abbreviated IdentificationAbbreviated Identification

E. coliE. coli– Non-swarming, spot indole pos, oxidase Non-swarming, spot indole pos, oxidase

negneg1.1. Lactose positive (MacConkey or eosin Lactose positive (MacConkey or eosin

methylene blue), PYR (pyrrolidonyl methylene blue), PYR (pyrrolidonyl arylamidase) test positivearylamidase) test positive

2. 2. APIAPI

Abbreviated IdentificationAbbreviated Identification

Proteus Proteus spp.spp.– Swarming growthSwarming growth

– IndoleIndoleNegative: Negative: P. mirabilis/penneriP. mirabilis/penneri

– P. mirabilis: P. mirabilis: maltose neg, ornithine posmaltose neg, ornithine pos– P. penneri: P. penneri: maltose pos, ornithine negmaltose pos, ornithine neg

Positive: Positive: P. vulgarisP. vulgaris

Abbreviated IdentificationAbbreviated Identification

P. aeruginosaP. aeruginosa– Oxidase-positive bacillusOxidase-positive bacillus– Typical smell (grapes)Typical smell (grapes)– Colony morphology Colony morphology P. aeruginosa: P. aeruginosa:

metallic/pearlescent, rough, pigmented, metallic/pearlescent, rough, pigmented, mucoidmucoid

– Indole-negativeIndole-negative

Abbreviated IdentificationAbbreviated Identification CHROMagar Orientation CHROMagar Orientation

– Presumptive ID for some UTI pathogens Presumptive ID for some UTI pathogens E. coliE. coli (dark rose to pink) (dark rose to pink) Enterococci (turquoise blue)Enterococci (turquoise blue) S. saprophyticus S. saprophyticus (light pink to rose)(light pink to rose) S. agalactiae S. agalactiae (light blue-green to light blue)(light blue-green to light blue) Proteus-Morganella-ProvidenciaProteus-Morganella-Providencia group (brown) group (brown) Klebsiella-Enterobacter-SerratiaKlebsiella-Enterobacter-Serratia group (dark blue) group (dark blue)

– Issues and challengesIssues and challenges All except All except E. coliE. coli and enterococci require further ID and enterococci require further ID

– Small Small E. coli E. coli colonies require spot indole colonies require spot indole Poor growth of some gram-positive bacteria Poor growth of some gram-positive bacteria NonselectiveNonselective–– other pathogens may or may not other pathogens may or may not

produce color changeproduce color change

Abbreviated IdentificationAbbreviated Identification

Enterococcus Enterococcus spp.spp.– Cocci or coccobacilli in pairs and chainsCocci or coccobacilli in pairs and chains– >1 mm colonies>1 mm colonies– Non-hemolytic on SBANon-hemolytic on SBA– Catalase-negativeCatalase-negative– PYR-positivePYR-positive(pyrrolidonyl-(pyrrolidonyl--naphthylamide -naphthylamide

hydrolysis)hydrolysis)

S. agalactiae S. agalactiae (GBS)(GBS)– Cocci in pairs and chainsCocci in pairs and chains– Catalase-negativeCatalase-negative– Narrow zone of beta-hemolysis on SBANarrow zone of beta-hemolysis on SBA– Rapid hippurate hydrolysis test (beta strep only) Rapid hippurate hydrolysis test (beta strep only) OROR– Test for CAMP factor (spot or O/N) Test for CAMP factor (spot or O/N) OROR– Typing by particle agglutinationTyping by particle agglutination– R/O beta hemolytic R/O beta hemolytic EnterococcusEnterococcus (PYR+) (PYR+)

Abbreviated IdentificationAbbreviated Identification

-hem Enterococcus

YeastYeast– Candida albicansCandida albicans

Microscopy required: oval, budding yeastMicroscopy required: oval, budding yeast Colonies <48 h old on blood-containing medium with Colonies <48 h old on blood-containing medium with

““feetfeet”” or mycelial projections or mycelial projections

*CHROMagar*CHROMagar

Abbreviated IdentificationAbbreviated Identification

Candida Candida CHROMagarCHROMagar

Abbreviated IdentificationAbbreviated Identification

Why females has higher incidence Why females has higher incidence of UTIof UTI ?? ??

Short urethraShort urethra Anus nearby urethra Anus nearby urethra contraceptivescontraceptives

Now to the labNow to the lab……