MLT – Microbiology Questions And Answers

MLT – Microbiology Questions And Answers A Brucella isolate that does not produce H2S, does not require CO2, and is not inhibited by thionin or basic fuchsin is probably what species of Brucella? -Answer-B. melitensis A colony of no hemolytic, catalase-positive, coagulase-negative, GPC is most likely to be what organism? -Answer-S. epidermis’s A curved, Gram-negative rod that is nonfermentative, nitrate positive, and microaerophilic is probably what organism? -Answer-Campylobacter jejuni A fastidious, oxidase-positive Gram-negative cocci from a rectal swab might be presumptively identified as what organism? -Answer-Neisseria gonorrhoeae A fastidious, small to filamentous, Gram-negative rod from a nasopharyngeal swab is most likely to be what organism? -Answer-Haemophilus influenzae A Gram-negative rod isolated from a stool culture has the following reactions: Urease Neg, PAD Neg, Lysine decarboxylase Neg, Motility Neg, Citrate Neg. What is the mostly likely ID of the organism? -Answer-Shigella dysenteriae A Gram-negative rod isolated from a urine culture has the following reactions: IMViC ++--, Motility Pos, Urease Neg. What is the most likely ID of the organism? -Answer-E. coli A gram-negative rod was isolated from a blood culture with the following biochemical reactions: Urease Pos, PAD Pos, Citrate Pos, Motility Pos. What is the most likely ID of the organism? -Answer-Proteus mirabilis A motile, Gram-negative, slender, curved rod that is the cause of enteritis is best isolated on which agar? -Answer-Campylobacter blood agar A mucoid colony on blood agar medium indicates that which characteristic may be present? -Answer-organism has a capsule A mucoid, lactose-fermenter was isolated from a sputum specimen on MacConkey agar. The organism has the following biochemical reactions: Motility Neg, Oxidase Neg, Citrate Pos. What is the most likely ID of the organism? -Answer-Klebsiella pneumoniae A positive coagulase test is observed for what? -Answer-clotting of plasma A relatively slow growing and fastidious, GNR that produces a characteristic brown pigment on Feely-Gorman iron cysteine agar is most probably what organism? -Answer-Legionella pneumophila A slow-growing, unbranched, acid-fast bacilli that is nitrate negative and niacin negative is most likely what organism? -Answer-Micobacterium bovis Acid-fast bacteria appear what color microscopically? -Answer-red Acid-fast organisms in tissue are best stained by what method? -Answer-Kinyoun act against Gram-negative bacteria -Answer- act against Gram-positive bacteria -Answer- After inoculating the Mueller-Hinton plates for the Kirby-Bauer susceptibility test, how long should the plates dry before the disks are added? -Answer-at least 3 minutes, but not more than 15 minutes alkaline slant/acid deep -Answer-red or yellow bacteria/glucose positive & non-lactose fermenters All of the following are characteristics of broad-spectrum antibiotics? -Answer-act against bacterial and nonbacterial organisms An oxidase-positive, Gram-negative cocci from a throat culture might be what organism? -Answer-Moraxella catarrhalis Babes-Ernest granules are characteristic of what organism? -Answer-Corynebacterium diphtheriae Bacteriostatic agents do what? -Answer-inhibit the growth of the organism Capsules are the basis of which test? -Answer-serotyping Clue cells may be found in infections with what organism? -Answer-Gardnerella vaginalis Cultures of Staphylococcus aureus supply which cultures of Haemophilus? -Answer-V factor Cutaneous larva migrans or creeping eruption is caused by what organism? -Answer-Ancylostoma braziliense Enteric cytopathic human orphan viruses are also known by what name? -Answer-echoviruses