CORYNEBACTERIUM

Question 1

• Catalase positive, gram-positive rods
• Non–acid-fast, non–spore-forming, and mostly
  non-branching rods

Answer 1

CORYNEBACTERIUM

Question 2

C. jeikeiumand C. urealyticum

Answer 2

Lipophilic Corynebacteria

Question 3

o C. diphtheriae, C. pseudotuberculosis,
C. pseudodiphtheriticum, C. striatum, C.
ulceransand C. xerosis

Answer 3

Non-Lipophilic Corynebacteria

Question 4

a can be divided into non lipophilic
and lipophilic species
* Majority of the species are found as indigenous
microbiota of the skin and mucous membrane of
humans and animals. Species are pathogenic to
animals, plants, and humans.

Question 5

found in fresh water.
Corynebacterium are also found in salt water,
soil, and air

Question 6

Species are non-motile, non-encapsulated, nonspore forming and highly theomorphic rod

Question 7

Specie are glucose and maltose fermenters
except

Answer 7

C. pseudodiphthericum and C. urealyticum.

Question 8

slightly curved, grampositive rods

Question 9

“club shape” or coryneform

Question 10

Cells are arranged singly, in “palisades” of
parallel cells or in pairs of cells connected after
cell division to form V or L shapes: “Chinese
letters” appearance

Question 11

“diphtheria-like

Question 12

Specie causing human infections in Corynebacterium

Answer 12

C.
diphtheriae, C. jeikeium, C. pseudotuberculosis,
C. pseudodiphthericum, C. ulcerans, and C.
urealyticum

Question 13

Majority of the species are found as indigenous microbiota of the skin and mucous membrane of humans and animals. Species are pathogenic to animals, plants, and humans.

Answer 13

CORYNEBACTERIUM

Question 14

AKA: diphtheria bacillus or Kleb-Loffler bacillus

Answer 14

CORYNEBACTERIUM DIPHTHERIAE

Question 15

Facultative anaerobe, Inhabits the human nasopharynx in carrier

Answer 15

CORYNEBACTERIUM DIPHTHERIAE

Question 16

inhalation of contaminated respiratory droplets or direct contact with infected cutaneous lesions.

Answer 16

MOA for Corynebacterium diphtheriae

Question 17

Readily killed by heat and by most of the usual disinfectants.
• Glucose and maltose fermenter

Answer 17

CORYNEBACTERIUM DIPHTHERIAE

Question 18

VF OF CORYNEBACTERIUM DIPHTHERIAE

Answer 18

Diphtheria toxin

Question 19

Preferred medium for Preferred medium

Answer 19

Enriched medium with
serum, cysteine and potassium tellurite

Question 20

o Rounded ends and “club-shaped swelling”
o highly pleomorphic cells are arranged in pairs and create X, V, Y and L formation that closely resembles Chinese letters.

Answer 20

Microscopy of CORYNEBACTERIUM DIPHTHERIAE

Question 21

(-) Urease; (+) Nitrate reduction.

Answer 21

Biochemical Test for CORYNEBACTERIUM DIPHTHERIAE

Question 22

Nasopharyngeal and throat swabs

Answer 22

Best specimen for CORYNEBACTERIUM DIPHTHERIAE

Question 23

THREE BIOTYPES OF CORYNEBACTERIUM DIPHTHERIAE

Answer 23

• Intermedius
• Mitis
• Gravis

Question 24

Very small, flat, dry, and grayish-black
colonies; non-haemolytic

Answer 24

Intermedius

Question 25

Small, black and convex that have “fried-egg appearance

Answer 25

Mitis

Question 26

Large, flat and dark gray colonies “daisy-head appearance”

Answer 26

Gravis

Question 27

used for the visualization of metachromatic granules which is also known as Much granules.

Answer 27

Albert stain

Question 28

• Heat-labile • Produced by strains with a lysogenic b-phage that carries the TOX gene.

Answer 28

DIPHTHERIA TOXIN

Question 29

• Tissue necrosis and exudates formation (psedomembrane lining) over the tonsils, larynx and pharynx • Alkaline pH (7.8 to 8.0), aerobic environment and sufficient amount of iron in the medium.

Answer 29

DIPHTHERIA TOXIN

Question 30

Acute, infectious disease characterized by production of systemic toxin and false membrane lining (Pseudomembranous formation) of the throat mucous membrane → respiratory obstruction.

Answer 30

RESPIRATORY DIPHTHERIA

Question 31

(+): 4 mm to 5 mm fine precipitin lines at 45 angle to the streaks.

Answer 31

Immunodiffusion Test - Elek’s Test

Question 32

AKA: diphtheria antitoxin test (in vivo test)

Answer 32

Guinea pig lethal Test

Question 33

detection of diphtheria antitoxin (in vitro)

Answer 33

Tissue Culture Test

Question 34

used for detection of toxin genes

Answer 34

Polymerase Chain Reaction

Question 35

Preferred medium for isolation and identification of crynebacterium

Answer 35

Cystine Tellurite Blood Agar

Question 36

o Modification of the Tinsdale agar o Selective and Differential o Contains sheep blood, bovine serum, cysteine

Answer 36

Cystine Tellurite Blood Agar

Question 37

Positive reaction for Cystine Tellirite Blood Agar

Answer 37

Colonies of corynebacterial exhibit a black or brown color after 48 hours

Question 38

C. diphtheriae, C. ulcerans and C. pseudotuberculosis.

Answer 38

Positive organism for CTBA

Question 39

Sheep blood, cystine, potassium tellurite and sodium thiosulfate

Answer 39

Tinsdale Agar

Question 40

o (+) Black color surrounded by halo o (+) all bio types of C. diphtheriae

Answer 40

Tinsdale Agar

Question 41

Urea production: C. urealyticum

Answer 41

Christensen Urea Slant

Question 42

Microscopic and metachromatic granules of C. diphtheriae.

Answer 42

Pai’s Slant or Loeffler’s Serum Agar

Question 43

(+): C. diphtheriae exhibit “poached- egg” appearance

Answer 43

Pai’s Slant or Loeffler’s Serum Agar

Question 44

Metachromatic diphtheriaeare called

Answer 44

Babes ernst bodies

Question 45

o Used to determine the susceptibility of a person to diphtheria. o Involves the intradermal introduction of a small amount of the diphtheria toxin into the arm of the suspected individual.

Answer 45

Schick Test

Question 46

(+): Redness and Swelling around the site.

Answer 46

Schick Test

Question 47

Most frequently isolated and most clinically significant. • Urinary pathogen, strict aerobe and lipophilic • Do not ferment glucose and maltose • Microscopy: V shaped and palisades • Culture: BAP –pinpoint, white smooth, non- haemolytic • Urease producer • Most frequent isolated and most clinically significant among them all.

Answer 47

C. UREALYTICUM

Question 48

• Normal flora of nasopharynx • Respiratory infection, UTI, cutaneous wound infection in immunocompromised. • Microscopy: arranged in parallel rows or palisades and do not exhibit any other characteristics “pleomorphism” that is similar to other. • Urease and nitrate positive

Answer 48

C. PSEUDODIPHTHERITICUM

Question 49

• Skin normal flora in inguinal, axillary and rectal sites. • Obligate aerobe and antibiotic resistant • Immunocompromised, Common cause of diphtheroid prosthetic valve endocarditis in adults. • Microscopy: Pleomorphic, club-shaped and arranged in V-shaped • Urease and Nitrate negative

Answer 49

C. JEIKEIUM

Question 50

• Animal contact and unpasteurized dairy products. • Skin ulcers and exudative pharyngitis • Associated with diphtheria-like sore throats. • Culture: BAP-narrow zone of b-hemolysis • CTBA - brown halo • Loeffler’s serum agar: Exhibit growth • (+): Urease and gelatinase; (-) nitrate reduction.

Answer 50

C. ULCERANS

Question 51

• Animal pathogens that human can contract thru direct contact with infected animals. • Dermonecrotic toxin causes death of various cell types • Diphtheria toxin (causative agent) • Culture: CTBA –black color and surrounded by brown halo • BAP: small and yellowish-white • (+) urease; (-) gelatinase

Answer 51

C. PSEUDOTUBERCULOSIS

Question 52

Preferred for collection.

Answer 52

Calcium alginate swa