The CAMP reaction is a prompt and reliable procedure for the presumptive identification of group B streptococci when a candle jar atmosphere is used during incubation
.
What is difference between camp and reverse CAMP test?
Reverse CAMP test can be used for differentiation of Clostridium perfringens from other Clostridium species
. Here, a CAMP test positive Group B Streptococcus is streaked in the center of sheep blood agar, and Clostridium perfringens is streaked perpendicular to it.
How does reverse CAMP test work?
A reverse CAMP reaction is a reaction whereby
hemolysis by the beta-hemolysin of staphylococci is inhibited through the production of phospholipase C or D by some organisms
(e.g., S. agalactiae, Listeria, Corynebacterium spp., and Clostridium perfringens).
Why it is called reverse CAMP test?
Alpha toxin producing C. perfringens and group B, β-haemolytic streptococci grow in a characteristic pattern on blood agar. The test is called reverse CAMP test
because CAMP factor produced by S. agalactiae is used for the detection of Clostridium perfringens from other Clostridium species
.
What does a CAMP test show?
The CAMP test (Christie–Atkins–Munch-Peterson) is a test to identify group B β-hemolytic streptococci (Streptococcus agalactiae) based on their formation of a substance (CAMP factor) that enlarges the area of hemolysis formed by the β-hemolysin elaborated from Staphylococcus aureus.
What organisms are CAMP test positive?
A number of other gram-positive and gram-negative bacteria are known to react positively in the CAMP test, including Rhodococcus equi (9), Pasteurella haemolytica (8), Listeria monocytogenes, Listeria seeligeri (27), Aeromonas sp. (7), certain Vibrio spp. (18), and group G streptococci (34).
What is a positive reverse CAMP test?
A positive reverse CAMP result, shown by Clostridium perfringens, is
a “bow tie” or reversed arrow zone of enhanced hemolysis at the junction of the two cultures
(Fig. 5) (1, 8).
What is camp factor?
CAMP factor is
a diffusible, heat-stable protein produced by group B streptococci
. This is a synergistic test between Staphylococcus aureus and Streptococcus agalactiae. S. agalactiae produces CAMP factor.
What does beta hemolysis look like?
Beta-hemolysis (β-hemolysis), sometimes called complete hemolysis, is a complete lysis of red cells in the media around and under the colonies:
the area appears lightened (yellow) and transparent
. Streptolysin, an exotoxin, is the enzyme produced by the bacteria which causes the complete lysis of red blood cells.
Is C. perfringens reverse CAMP positive?
The reverse CAMP test proved to be a highly sensitive test since
97.0% of all Clostridium perfringens cultures tested gave an easily discernible positive reaction
.
Is CAMP test selective or differential?
CAMP Test. CAMP factor is a
diffusible
, heat-stable protein produced by group B streptococci. This is a synergistic test between Staphylococcus aureus and Streptococcus agalactiae.
What is hippurate hydrolysis?
Hippurate hydrolysis test is
used to detect the ability of bacteria to hydrolyse substrate hippurate into glycine and benzoic acid by action of hippuricase enzyme present in bacteria
. Hippuricase is a constitutive enzyme that hydrolyzes the substrate hippurate to produce the amino acid glycine.
What is Nagler’s reaction?
Lecithinase test or Nagler’s reaction is
a biochemical test used to identify organisms that liberate phospholipases (lecithinases) e.g. Clostridium perfringens
.
What is double zone of hemolysis?
On blood agar, the colonies are typically surrounded by a “double zone of hemolysis”:
an inner zone of complete hemolysis that is due to θ-toxin and a larger outer zone of incomplete hemolysis that is due to α-toxin
.
