Bacte Flashcards
How is preparation for 100 ml of Kinyoun’s carbolfuchsin done?
A) 4 g basic fuchsin, 8 g phenol, 20 mL 95% alcohol, 100 mL distilled water
Which of the following compounds do not contribute to the acid-resistance and waxy character of the mycobacterial cell wall
N-acetylmuramic
Which of the following statements best supports the action of the detergent in Kinyoun’s method?
Detergent is used to force the carbolfuchsin into the mycobacterial cell wall
How would you describe acid-fast bacteria under the brightfield microscope using your Ziehl-Neelsen stain?
Red microorganisms on a blue background
An acid-fast smear on the Ziehl-Neelsen stain was reported as 2/50 fields on a 1000x magnification using the WHO/IUATLD standards. How would you report your findings?
2+
The KOH technique is used to aid in the identification of fungal infections, specifically dermatophytes. Which of the following is not a common dermatophyte?
Aspergillusniger
Which fungi listed below is most commonly found in nails and causes onychomycosis?
Tinea unguium
How is it that fungi can resist the keratin dissolving effects of potassium hydroxide?
Fungi contains chitin which resists the effects of KOH
Which urine is not acceptable for bacterial culture?
Routine (B)
Proper concentration for blood culture?
C
How many mL of blood chuchu in immunocompromised patient
20 (B)
Term used to describe your reduced O2 (10%) and CO2 (10%)
Microaerophiles
Time to transport CSF in lab
15 mins (D)
Best time to collect sa patient
before antibiotic (A)
Stain chuchu Bastia may picture ni si ya nag spirochetes
Silver Nitrate
Dye that can stain mycobacterium -
Crystal violet ( A)
Culture media that contains antibiotics and selective for neisseria
Thayer martin (D)
True/False) 1st statement: acid alcohol decolorize acid fast bacilli 2nd statement: mixing… 5%HCL 95% absolute alcohol
Both false
(True/False) 1st statement: Nigrosin detects capsule 2nd statement: New field detects capsular antigen
Both true
Case Ana: 25yr old sexually active….basta ang ngaman hndi ma stain ang T.pallidum
diameter is < 0.2
Swab used for vagina and cervix
Rayon
Media nga maka hold for 72 hrs
Thioglycollate
indicator of autoclave
Bacillus stearothermophilus
What is the principle of gram staining?
differential stain
In Eosin-methylene blue agar, lactose fermenters appear ____ while non-lactose fermenters appear ____?
Violet, clear
Which biochemical test differentiates staphylococcus against streptococcus and enterococcus?
Catalase test
Staphylococcus aureus is catalase ___ and coagulase ___?
Positive, positive
S. epidermidis is catalase ___ and coagulase ___?
Positive, negative
Which of the ff exhibits a brown halo in cystine- tellurite blood agar (CTBA)?
C. dipthriae
Which of the ff is normal flora of the colon, gives a characteristic horse manure odor and is responsible for causing pseudomembranous colitis?
C. difficile
Which of the ff has characteristics burnt flesh color in RCM and is responsible for trismus/lock jaw, opisthotonos and spasm of facial muscles?
C. tetani
What is a highly pleomorphic, club-shaped microorganism which produces leather-like lesions creating a pseudomembrane which can lead to lung paralysis in severe case?
C. diptheriae
Which of the ff characteristics describe true for Micrococcus spp.?
Gram positive cocci in circular tetrads
I. CAMP test positive result is an arrowhead or bowtie hemolysis.
II. CAMP Stands for Christine, Atkinson, Munch and Peterson Test
First statement is true, Second statement
is false
Mycobacterial disease wherein patient presents “leonine facie” with presence of skin lesions and symmetric nerve damage due to ineffective cell- mediated immune response?
Lepromatous leprosy
Stefan Salvatore was experiencing low grade fever, night sweat, sudden weight loss and was expectorating sputum streaked laden with blood. If the patient will pay the physician a visit, the physician will likely request for?
Kinyoun staining of sputum smear
Brienne Tarth complained of a persistent pruritic rash throughout her body after making a tip to Mexico. She appeared to be well nourished but her physical exam revealed lesions across her nasal bridge area, cheeks and abdomen. If the patient will pay the physician a visit, the physician will likely request for?
Biopsy of skin lesions subjected to ziehl-
neelsen
Fecility Smoak was admitted to a nearby hospital due to malaise, nonproductive cough and shortness of breath. She had daily fevers, night sweats and a recent 5kg weight loss. She shared that her mother dies of tuberculosis when she was only an infant. Liver and bone marrow biopsies showed granulomas with presence of AFB. She is probably infected with?
M. tuberculosis
A MT isolated a bacterium with ff characteristics: appear as cigarette packets under the microscope, catalase positive, gun metallic gray on CTBA and bull’s neck appearance of those infected by this bacterium. Which of the ff is the probable isolate?
C. diptheriae
Which of the ff products below is detected by VP test?
Acetoin
Which of the ff biochemical tests is used to identify non-lactose fermenters from late lactose fermenters?
ONPG test
Which of the ff enterics are known to cause diarrhea and re considered pathogens?
Samonella, shigella and yersinia
When grouped according to habitat, which of the ff is a trye enteric pathogen?
Y. enterocolitica
When grouped according to habitat, which of the ff is a true non-enteric pathogen?
Y. pestis
Pseudomonas aeruginosa can be diagnosed from the pigment known as ___?
Pyocyanin
Identify a selective medium that allows the isolation of N. gonorrheae and N. meningitidis?
Modified Thayer-Marin Agar
A microorganism that can grow in the small bowel and cause diarrhea in children, traveler’s diarrhea or a severe cholera like syndrome through enterotoxin production?
E. coli
TSIA reaction of P. aeruginosa?
K/K H2S –
A TSIA inoculated with an organism gave the ff reactions: Alkaline slant/acid butt. No gas production nor H2S production. This microorganism likely?
S. dysentariae
A TSIA inoculated with an organism gave the ff reactions: Acid slant/ acid butt. Gas production, no H2S production. This microorganism likely?
K. pneumoniae
Ornithine decarboxylase positive, indole negative with a characteristics burnt gun powder odor and swarming growth?
P. mirabilis
A group of elementary students became ill after earing undercooked ground beef prepared in the school cafeteria. The suspected pathogen, E. coli serotype 0157:H7 is usually recovered using which of the following media?
MacConkey agar with sorbitol
Which of the ff is the pH indicator in TSIA?
Phenol red
Which of the ff strains of E.coli is capable of using Hemolytic Uremic Syndrome (HUS)?
EHEC 0157:H7
Which of the ff microorganisms ferment glycose and lactose produces gas, has negative reaction
with H2S?
Klebsiella spp.
Which of the ff microorganism ferment glucose, does not produce gas, has a negative reaction with H2S?
Shigella spp.
What is the purpose of a mordant?
Upon the addition of mordant, lodine interacts with the CV+ to form CV-I complex which will attach to the cell wall, enlarging the complex making it hard to wash out.
What is the reason why AFS is considered as a presumptive test for Tb and not a confirmatory test?
There are different acid fast bacilli thus other confirmatory tests are performed
