SEMIFINAL: Neisseria & Moraxella Flashcards
1
Q
All species are cytochrome oxidase and catalase positive except for?
A
N. elongata subsp. nitroreducens and N. bacilliformis
2
Q
Considered second most
commonly reported STDs
A
Gonorrhea
3
Q
Localized to the mucosal surfaces (urethra, endocervix, anal canal, pharynx, and conjunctiva)
A
Neisseria gonorrhoeae
4
Q
This may cause sterility, ectopic pregnancy, or perihepatitis (Fitz-Hugh–Curtis syndrome)
A
Pelvic inflammatory disease
5
Q
A gonococcal eye infection during vaginal delivery through an infected birth canal
A
Ophthalmia neonatorum
6
Q
Treatment for opthalmia neonatorum
A
Antimicrobial eye drops, generally erythromycin
7
Q
These species of Neisseria is exclusively found only in
humans
A
N. meningitidis & N. gonorrhoeae
8
Q
When N. meningitidis enters the bloodstream, two main diseases can occur
A
fulminant meningococcemia & meningitis
9
Q
This may occur with or without meningitis and carries a 25% mortality rate, even if treated
A
Meningococcemia, or sepsis
10
Q
Hemorrhaging of blood into skin and mucous
membranes, producing bruises
A
Purpura
11
Q
Enumerate the virulence factors of Neisseria
A
- Receptors for human transferrin
- Capsule (N. meningitidis)
- Pili (fimbriae)
- Cell membrane proteins
- Lipooligosaccharide (LOS) or endotoxin
- Immunoglobulin A (IgA) protease
12
Q
Fine hairlike projections that are important in the initial attachment of the organism to host tissues
A
Pili (fimbriae)
13
Q
Inhibit phagocytosis of the organism by neutrophils and aid in the exchange of genetic material between cells
A
Pili (fimbriae)
14
Q
Possesses a polysaccharide capsule that is antiphagocytic and serves as an important virulence factor
A
N. meningitidis
15
Q
Similar to lipopolysaccharide of enteric gram-negative bacilli and helps in the organism’s evasion of the complement mediated cell lysis
A
Lipooligosaccharide
16
Q
Other Neisseria spp.
A
- Saprophytic Neisseria
- Normal microbiota in respiratory culture
17
Q
It is extremely susceptible to drying and temperature change
A
N. gonorrhoeae
18
Q
Reduced recovery of N. gonorrhoeae may result as soon as _________ after collection
A
30 minutes
19
Q
When inoculated swabs are used in collecting neisseria samples, what transport system must be used?
A
Amie’s medium with charcoal
20
Q
What swabs are preffered for collecting neissseria samples?
A
Dacron or rayon swabs
21
Q
Why are calcium alginate and cotton swabs not used for collecting neisseria samples?
A
Because they are inhibitory to N. gonorrhoeae
22
Q
IDENTIFY:
Otitis media (young children)
Chronic upper respiratory infection
A
Moraxella catarrhalis
23
Q
These are aerobic, nonmotile, non–spore-forming, gram- negative diplococci.
A
Neisseria
24
Q
What is needed in order to grow Neisseria?
A
Carbon dioxide because Neisseria is capnophilic
25
These are plates utilize for bedside plating
Jembec Plates
26
These are sensitive to sodium polyanethol sulfunate which is found in blood culture bottle
N. gonorrhoeae & N. meningitidis
27
If a blood culture broth is inoculated, the SPS content should not exceed?
0.025%
28
If blood is first collected in vacutainer tubes containing the SPS, the specimen must be transferred to the broth cultured system within
1 hour of collection
29
Appearance of neisseria when gram stained
Kidney-shaped or coffee- bean shaped diplococci
29
This is diagnostic especially from a urethral discharge specimen, in men only
Gram negative diplococci inside a poymorphonuclear leukocytes
30
This should not be gram stained because nonpathogenic commensal Neisseria may be present and this is not diagnostic of the infection
Pharyngeal specimen
31
In symptomatic females, this is only presumptive evidence of gonococcal infection
direct examination of endocervical secretion
32
What is the media of choice for neisseria?
- Trypticase soy agar with 5 % sheep blood
- Chocolate Agar (CA)
- Selective medium
such as:
Thayer-martin medium
MTM
Martin-Lewis
GC-LECT
NYC medium
33
Has chocolate agar as base; enriched with IsoVitaleX supplement
Thayer- Martin
34
This inihibits gram-negative bacteria in Thayer-Martin
Colistin
35
This inhibits yeast in Thayer-Martin
Nystatin
36
This inhibits gram-positive bacteria in Thayer-Martin
Vancomycin
37
What are the antibiotics or inhibitory agents of Thayer-Martin?
- Vancomycin
- Colistin
- Nystatin
38
This inhibits swarming Proteus spp. in MTM
Trimethoprim
39
What are the antibiotics or inhibitory agents of Martin Lewis?
- Colistin
- Anisomycin
- Vancomycin
40
What are the antibiotics or inhibitory agents of MTM?
- Colistin
- Nystatin
- Trimethoprim
41
Contains additional antimicrobials to inhibit bacteria found in oropharyngeal specimen specifically N. meningitidis
GC-LECT
42
What are the antibiotics or inhibitory agents of GC-LECT?
- Colistin
- Amphotericin B
- Vancomycin & Lincomycin
- Trimethoprim
43
This inhibits yeast in GC-LECT
Amphotericin B
44
This inhibits growth of gram positive bacteria in GC-LECT
Vancomycin & Lincomycin
45
This inhibits yeast in Martin Lewis
Anisomycin
46
Transparent clear to yellow medium containing lysed horse blood, horse plasma, yeast dialysate, and the same antimicrobials as to that of MTM
New York City Medium
47
Inhibits the growth of genital mycoplasma or Ureaplasma urealyticum
New York City Medium
48
N.gonorrhoeae, N. meningitidis, & M. catarrhalis grow best in increase....?
Carbon dioxide around 3-7%
49
Why should you not use Scented or colored candles in candle extinction jar?
Because it is inhibitory to gonococci
50
Are occasionally able to grow on gonococcal selective media
Gram-negative rods, such as Kingella & Acinetobacter spp.
51
It appears as GN rod form in 10-unit penicillin disk test
Kingella
52
It appears as GN Diplococcia form in 10-unit penicillin disk test
Neisseria
52
It appears as GN elongated and filamentous in 10-unit penicillin disk test
Acinetobacter spp.
53
Oxidase reagent
1% dimethyl-p-phenylenediamine dihydrochloride or
tetramethyl-p-phenylenediamine dihydrochloride
53
This test must be done on all suspected isolates of N. gonorrhoeae
oxidase test
54
Positive reaction for oxidase test (filter paper)
a purple color develops within 10 seconds
55
Positive reaction for oxidase test (reagent dropped directly onto colony)
the colony turns deep
purple to black.
56
What is the standard method of identification of Moraxella and Neisseria species?
- Acid production from glucose, maltose, lactose, sucrose, and fructose in a CTA base medium and a carbohydrate-free control
(HISTORICALLY)
- Buffered, low peptone substrate with the appropriate carbohydrate
57
The test is used to determine the ability of an organism to hydrolyze DNA
DNase Test
58
The medium used in DNase test is pale green because of the?
DNA-methyl green complex
59
In DNase test, if the organism growing on the medium hydrolyses DNA the _____ fades and the colony is surrounded by a __________
green color and colorless zone, respectively
60
In the presence of hydrochloric acid, it is DNase positive when there is a clear zone surrounding the inoculum, streak with the rest of the plate remaining ______. The positive reaction takes approximately _____________ to form
opaque and 5 minutes, respectively
61
Used for differentiating M. catarrhalis from Neisseria
DNase test
62
IDENTIFY: Absence of a clear halo around the inoculum streak.
DNase negative in the presence of hydrochloric acid
63
In the presence of toluidine blue, it is DNase positive when there is an appearance of a _______ surrounding the inoculum streak. The rest of
the plate remains ________
pink halo and blue, respectively
64
IDENTIFY: Absence of the pink halo surrounding the inoculum streak
DNase negative in the presence of toluidine blue
65
Also used to distinguish Serratia from Enterobacter and Staphylococcus from other species
DNase test
66
These are DNase positive bacteria
Serratia & S. aureus
67
The traditional method for the identification of Neisseria spp. was
carbohydrate utilization in cystine trypticase agar (CTA)
68
Contains 1% of the individual carbohydrate and phenol red as a pH indicator
Cystine trypticase agar (CTA)
69
If the organism uses the particular carbohydrate, acid, it is characterized by?
yellow color in 24-72 hours
70
What is the expected negative result in carbohydrate utilization method- CTA?
No color change compared to control uninoculated tube
70
What is the expected positive result in carbohydrate utilization method- CTA?
Yellow color at the top of the tube only (indicating carbohydrate utilization)
71
TRUE OR FALSE:
In carbohydrate utilization method- CTA, you need to avoid incubation in oxygen because it may alter the media, resulting in a color change to yellow throughout the entire tube and a false-positive
FALSE. you need to avoid incubation in carbon dioxide (CD)
72
In carbohydrate utilization method- CTA, N. gonorrhoeae is positive for?
Glucose ONLY
73
In carbohydrate utilization method- CTA, N. lactamica is negative for?
Sucrose ONLY
74
In carbohydrate utilization method- CTA, N. meningitidis is positive for?
Glucose & Maltose
75
In carbohydrate utilization method- CTA, nonpathogenic Neisseria spp., is negative for?
Lactose ONLY
76
In carbohydrate utilization method- CTA M. catarrhalis is negative for?
ALL (glucose, maltose, lactose, and sucrose)
77
IDENTIFY:
Principle- PCR amplification target gene
Cobas CT/NG Test
78
IDENTIFY:
Principle- Real time PCR
Xpert CT/NG
79
IDENTIFY:
Principle- target amplification
APTIMA GC or APTIMA Combo2
80
IDENTIFY:
Principle- Strand displacement amplification
BD ProbeTec ET
81
IDENTIFY:
Principle- PCR amplification
Abbott RealTime CT/NG
82
These are the preferred assays for the detection of N. gonorrhoeae in clinical specimens because of increased sensitivity, specificity, and
ability to test with a noninvasive urine specimen
Nucleic acid amplification tests (NAATs)
83
These have the additional advantage of being less sensitive to transport and storage conditions compared with culture
Nucleic acid amplification tests (NAATs)
84
NAAT is not recommended for:
- child sexual assault involving boys
- extragenital infections (i.e., rectal, oropharyngeal) in prepubescent girls
85
NAATs can also detect both ___________ and __________ in the same specimen
N. gonorrhoeae and C. trachomatis, respectively
86
This is the preferred method for testing urethral specimens from boys or extragenital specimens from boys and girls
Culture
87
The only method to monitor the effectiveness of treatment because NAATs are not approved for use as a test of cure
Culture
88
This is necessary to monitor antimicrobial resistance.
N. gonorrhoeae
89
Chromogenic Substrate Enzyme test used for N. gonorrhoeae
prolyl-hydroxylprolyl aminopeptidase
90
Chromogenic Substrate Enzyme test used for N. meningitidis
beta-galactosidase and gammaglutamyl
aminopeptidase
91
This test is done to differentiate the N. lactamica from N. meningitidis and where you can determine an organisms ability to produce beta-galactosidase (enzyme present in lactose fermenter)
O- Nitrophenyl- B- D- Galactopyranoside (ONPG) test
92
This bacterium may grow on selective media and may be confused with N.meningitidis
N. lactamica
93
What bacteria is ONPG positive?
Neisseria lactamica
94
What bacteria is ONPG negative?
N. meningitidis
95
This maybe misidentified as N. gonorrhoeae because it may appear false positive for glucose
N. cinerea
96
This is the only gram-negative bacteria that hydrolyzes DNase
M. catarrhalis
97
It can grow in BAP at 22°C and 35°C in nutrient agar
M. catarrhalis
98
Aside from M. catarrhalis, which specie of Neisseria is also negative for glucose, maltose, lactose, sucrose, and fructose acid production
N. flavescens
99
Aside from inhibiting yeast growth in Martin Lewis this also functions as antifungal agent
Anisomycin
100
In jembec plates, this would activate the tablet and generate a carbon dioxide atmosphere in the pouch
Moisture in the agar
101
This NAAT test method is manufactured by cepheid
Xpert CT/NG
102
This NAAT test method is manufactured by Roche Diagnostics
Cobas CT/NG Test
103
This NAAT test method is manufactured by hologic
APTIMA GC and APTIMA Combo2
104
What are the antibiotics or inhibitory agents of NYC
- Colistin
- Amphotericin B
- Vancomycin
- Trimethoprim
105
What is the ideal incubation condition and duration of Neisseria and Moraxella?
Incubation at 35C to 37C for 72 hours in a CO2-enriched humid atmosphere
106
In most microbiology laboratories, what kinds of incubators are used?
CO2 incubators that automatically humidify or pan of water that can be placed in the bottom
107
In this method of oxidase test, a colony from a plate is rubbed onto the reagent with an applicator stick or a non-nichrome loop
Filter paper method
108
This method of oxidase test is convenient but it renders the organism nonviable for subculture
Oxidase reagent dropped directly onto colony
109
This starts as nasopharyngeal colonization and develops to fatal bacterial meningitis
N. meningitidis
