Clostridium perfringens

Question 1

What is the shape of clostridium perfringens?

Answer 1

club shaped bacilii

Question 2

what type of hemolysis does clostridium perfringens show in blood agar?

Answer 2

On blood agar, the colonies are typically surrounded by a “double zone of
hemolysis”: an inner zone of complete hemolysis(beta hemolysis)  that is due to θ-toxin and a larger outer zone of
incomplete hemolysis (alpha hemolysis) that is due to α-toxin.

Question 3

Does clostridium perfringens produce catalase?

Answer 3

No

Question 4

What type of anaerobes are clostridium perfringens?

Answer 4

They are obligate anaerobes meaning they die at normal atmospheric concentrations of oxygen.

Question 5

What makes clostridium perfringens spores resistant to heat?

Answer 5

Dipicolinic acid

Question 6

How does clostridium perfringens enterotoxin work?

Answer 6

Clostridium perfringens enterotoxin targets the tight junctions in that connect the epithelial cell lining and destroy them causing inflammation and compromised structural integrity of the intestinal wall

Question 7

Explain how Naglers reaction is used to test for C.Perfringens

Answer 7

C. perfringens is cultured on an egg yolk
media plate. One side of the plate contains
anti-alpha-toxin, while the other side does
not.
A streak of C. perfringens is placed through
both sides. At the side without anti-toxin,
opacity will be seen at the streak area due to
the breakdown of lecithin into diglyceride.

Question 8

What is a common disease of clostridium perfringens?

Answer 8

clostridium perfringens enteritis enteritis

Question 9

What are the symptoms of clostridium perfringens enteritis?

Answer 9

Abdominal cramps
watery diarrhea
Vomiting

Question 10

What is the treatment for clostridium perfringens enteritis?

Answer 10

Most of the symptoms of clostridium perfringens enteritis improve over the course of the day as the bacteria makes its way through the digestive system so antibiotics are not needed, you only need to ensure the individual is well hydrated.

Question 11

What is another way clostridium perfringens can enter the body?

Answer 11

Clostridium perfringens can enter the body through wounds made by dirty sharp objects that were in the soil which is rich in C.Perfringens and other anaerobes

Question 12

What causes clostridial Myonecrosis?

Answer 12

This happens when there is a deep wound, and clostridial perfringens alpha toxin causes cells to swell up and lyse leading to rapid massive destruction of muscular and soft tissue. This leads to tissue death or gangrene.

Question 13

What are the symptoms of myonecrosis?

Answer 13

Extreme pain
swelling
Thin watery pus leaking out of the wound
Blood vessels can break forming blood filled bullae above the skin of gangrenous tissue
Fast moving infection can lead to massive tissue damage as well as fever and tachycardia, hypotension and shock leading to death.

Question 14

What is one of the classic signs of myonecrosis?

Answer 14

Crepitus, the sound of crackles being heard as you press down on the wound. It is also called gas gangrene

Question 15

What makes it hard to diagnose myonecrosis?

Answer 15

In the early stages, it is difficult to diagnose myonecrosis because it resembles cellulitis.

Question 16

What is the treatment of myonecrosis?

Answer 16

Complete and prompt surgical excision of the necrotic tissue including amputation if necessary
Supportive care to manage fluids and hemodynamics
High dose of antibiotic treatment of Penicillin V or clindamycin and broad spectrum antibiotics in very ill individuals
Hyperbaric oxygen can be used to kill clostridium perfringens.

Question 17

A 28-year-old man comes to the emergency department because of a painful wound on his arm for the past two days. He fell onto a decaying log while jogging on a forest trail, and sustained a deep laceration on his arm. He says it has grown progressively more painful since that time and seems to be spreading. His temperature is 38.1°C (100.6°F), pulse is 88/min, respirations are 16/min, and
blood pressure is 138/82 mm Hg. Physical examination shows a reddish-purple
necrotic lesion on the arm with gaseous distention and
crepitus of the surrounding tissue. A wound culture on blood agar shows a double-zone of both alpha and beta
hemolysis. What is most likely the case and why?

Answer 17

Clostridium perfringens is a gram-positive, rod-shaped, anaerobic, spore-forming pathogenic bacterium that is very common in nature and can be found as a normal component of decaying vegetation, soil, and the gastrointestinal tract. In traumatic open wounds
, the bacteria enters and causes gas gangrene. It releases a phospholipase, called alpha toxin, that eats cell membranes and thereby destroys tissues, releasing gas in the process. Gas gangrene is characterized especially by the degradation of muscle tissues, called myonecrosis. When cultured on blood agar, the bacteria produces a characteristic “double zone” of hemolysis.

Question 18

A 32-year-old woman comes to the emergency room because of pain in her arm. Physical examination shows that her arm is purple, and gas can be palpated beneath the Skin The woman has a history of injecting black tar heroin what is the most appropriate initial treatment strategy.

Answer 18

Myonecrosis is generally caused by Clostridium species, particularly Clostridium perfringens, or by group A Streptococcus (Streptococcus pyogenes). Clostridium species reside in soil as endospores and contaminate wounds. When anaerobic cellulitis
occurs, species such as C. perfringens proliferate and produce gas, which spreads along fascial plains. C. perfingens invades and destroys healthy muscle tissue
. It generally follows traumatic injury. Spontaneous gas
gangrene is usually caused by a separate species, C. septicum.
Treatment of traumatic gas gangrene requires surgical debridement. This should be done quickly, since debridement of necrotic tissue is important for improving survival, preventing limb amputation, and limiting complications of infection. It is common for a patient with gas gangrene to require multiple debridements.