What is the purpose of adding sodium polyanethol sulfonate (SPS) to nutrient broth media for the collection of blood cultures?

Select the media of choice for recovery of Vibrio cholerae from a stool specimen:

Blood agar plates are ideally prepared with 5% RBCs obtained from:

Cycloserine-cefoxitin-fructose agar (CCFA) is used for the recovery of:

Prereduced and Vitamin K₁ supplemented blood agar plates are recommended isolation media for:

Which procedure is appropriate for culture of genital specimens in order to recover Chlamydia spp.?

The Voges-Proskauer (VP) test detects which end product of glucose fermentation?

Which of the following reagents is added to detect the production of indole?

Which genera are positive for phenylalanine deaminase?

An isolate of E.coli recovered from the stool of a patient with severe bloody diarrhea should be tested for what sugar before sending to a reference laboratory for serotyping?

Which genera of Enterobacteriacea are usually nonmotile at 36^oC?

Which single test best separates Klebsiella oxytoca from Klebsiella pneumoniae?

The characteristics of being lactose negative, citrate negative, urease negative, lysine decarboxylase negative, and nonmotile best describe which organism?

In grouping Shigella organisms, agglutination by group B antisera indicates that the species is:

Pus with blue green-color was aspirated from empyema. A Gram stain of the aspirated material showed many WBCs and numerous gram-negative bacilli. The most likely etiologic agent in this case would be:

A visitor to South America returns with diarrhea, and infection with Vibrio cholerae is suspected. Select the best media for recovery and identification of this organism.

What atmospheric condition is needed to recover Campylobacter spp. from specimens inoculated onto a Campy-selective agar at 35-37^oC and 42^oC?

Which medium should be used to recover Bordetella pertussis from a nasopharyngeal specimen?

Which media is recommended for the recovery of Brucella spp. from blood and bone marrow specimens?

In addition to CO₂ requirement and biochemical characteristics, Brucella melitensis and Brucella abortus are differentiated by growth on media containing which two dyes?

Which medium is best for recovery of Legionella pneumophila from clinical specimens?

The majority of Haemophilus influenzae infections are caused by which of the following capsular serotypes?

Which Haemophilus sp. is difficult to isolate and recover from genital ulcers and swollen lymph nodes?

A spherical, gram-positive coccus that is catalase positive, non-motile and unable to produce acid from glucose anaerobically is best identified as a member of the genus:

Slime production is associated with which Staphylococcus species?

Bacitracin A disks (0.04 units) are used for the presumptive identification of which group of beta-hemolytic Streptococcus spp.?

Streptococcus pneumonia and Viridans streptococci can be differentiated by which test?

The salt tolerance test (6.5% salt broth) is used to presumptively identify:

The Quellung test is used to identify which Streptococcus spp.?

The L-pyrolidonyl-B-naphtylamide (PYR) hydrolysis test is a presumptive test for which streptococci?

Alpha-hemolytic streptococci recovered from a wound were found to be penicillin resistant. Given the following results, what is the most likely identification?

Bile esculin +

Bile solubility 0

6.5% salt +

SXT R

PYR +

A gram-positive coccus isolated from a blood culture has the following characteristics:

Optochin susceptibility-Negative

Bacitracin (0.04 U) susceptibility-Negative

Bile esculin hydrolysis-Negative

Hippurate hydrolysis-Positive

Catalase-Negative

This organism is most likely:

Modified Thayer-Martin (MTM) media is used primarily for the selective recovery of which organism from genital specimens?

The superoxol test is used as a presumptive test for:

Culture on Modified Thayer-Martin (MTM) medium of a vaginal swab produced several colonies of gram-negative diplococci that were catalase and oxidase positive and superoxol negative. Given the following carbohydrate reactions, select the most likely identification:

Glucose +

Fructose 0

Maltose +

Lactose +

Sucrose 0

Bacillus anthracis and Bacillus cereus can best be differentiated by which tests?

A non-spore-forming, slender gram-positive rod forming palisades and chains was recovered from a vaginal cultures and grew well on tomato juice agar. The most likely identification is:

A gram-positive branching filamentous organism recovered from a sputum specimen was found to be positive with modified acid-fast stain method. What is the most likely presumptive identification?

Which of the following organisms is the cause of Lyme disease?

Primary atypical pneumonia is caused by:

Which organism typically produces “fried-egg” colonies on agar within 1-5 days of culture from a genital specimen?

A direct smear from a nasopharyngeal swab stained with Loeffler’s methylene blue stain showed various letter shapes and metachromatic granules. The most likely identification is:

Which of the following is the best rapid, noncultural test to perform when Gardnerella vaginalis is suspected in a patient with vaginosis?

A gram-positive spore-forming bacillus growing on blood agar anaerobically produces a double zone of hemolysis and is positive for lecithinase. What is the presumptive identification?

Which spore type and location is found on C. tetani?

Which Clostridium spp. is most often recovered from a wound infection with gas gangrene?

A Gram stain smear taken from the periodontal pockets of a 30-year-old male with poor dental hygiene showed sulfur granules containing gram-positive rods (short diphtheroids and some unbranched filaments). Colonies on blood agar resembled “molar teeth” in formation. The most likely organism is:

Mycobacteria stained with Ziehl-neelsen or Kinyuon methods using a methylene blue counterstain, are seen microscopically as:

Acid-fast staining of a smear prepared from a digested sputum showed slender, slightly curved, beaded red mycobacterial rods. Growth on Middlebrook 7H10 slants produced buff-colored microcolonies with a serpentine pattern after 14 days at 37 ^oC. Niacin and nitrate reduction tests were positive. What is the most probable presumptive identification?