Infectious Disease Compendium



Anaerobic gram positive rod; includes C. botulinum, C. difficile (Clostridioides difficile) as of 2018. (PubMed), C. novyi, C. perfringens, C. ramosum, C. septicum, C. sordellii, C. tetani. Some are spore formers and exist forever in the environment.

Epidemiologic Risks

Most Clostridia are found in soil and gi tracts.


- C. botulinum: botulism. Progressive weakness usually starting with ocular muscles. A and B is contaminated food (besides canned goods has occurred with fresh carrot juice (PubMed), that's the problem with being a vegan) and wounds (has occurred in cocaine users, growing in a sinus), F is from fish. There have also been cases with the cheap and the vain (that would make a good movie title) using laboratory grade botulism toxin to self treat their wrinkles, which is far more concentrated than the commercial preparation.

There is also the newly discovered (2013) H for which there is no anti-toxin (PubMed).

Also occurs from drinking Pruno, illicit fruit based alcohol brewed in prison toilets. I can't make this stuff up (PubMed).

Black tar heroin is associated with wound botulism (PubMed) and some will get it more than once. Can you say addicting?

- C. novyi: soft tissues infections in heroin users, specifically Scottish heroin users laddie (PubMed).

- C. perfringens: Gas gangrene, one of the several necrotizing soft tissue infections. Skin popping drugs a major risk factor.

With gas gangrene: If you wait for gas in the diagnosis of gas gangrene, you might as well call the morgue. To make the diagnosis of gas gangrene, get a tissue gram stain. Carry it to the lab yourself, watch the tech stain it, look through the microscope and when you see a boxcar shaped, bipolar staining gram positive rod, swear softly to yourself and run, not walk, to the nearest phone for a surgeon, unless you are a surgeon. Then run like the Flash to the OR and get that patient debrided. This is a disease where you do not have a lot of time.

10% of outbreaks of gastroenteritis (PubMed); the classic being pig roasts.

- C. ramosum: Gas gangrene one of the several necrotizing soft tissue infections.

- C. septicum: sepsis from intra-abdominal source: often cecal cancer or lymphoma chemotherapy that kills the Peyers patches.

- C. sordellii: occasional bacteremia/sepsis esp after childbirth, abortion (? including after Mifepristone (RU-486), and in IVDA (PubMed). Usually fatal. A smattering of foot infections although not toxigenic strains and associated with bowel cancer (PubMed).

- C. tetani: tetanus aka lock jaw.


C. botulinum: Antitoxin therapy equine serum; in the United States can obtained from state health departments or the CDC (404-639-2206 workdays, 404-639-2888 other times). Wound botulism should be debrided PLUS penicillin, 10 to 20 million units qd OR metronidazole, but not proven to help.

Patients (in this case heroin users) who receive the antitoxin <12 hours after presentation do better.

Botulism can lead to permanent sequela (PubMed).

C. perfringens: penicillin OR metronidazole PLUS clindamycin PLUS debridement. Do not delay surgery for hyperbaric oxygen (unless the patient is suffering from the bends as well).

C. ramosum: penicillin/beta lactamase inhibitor combinations, imipenem, metronidazole.

C. septicum: penicillin PLUS clindamycin PLUS debridement.

C. sordellii: penicillin PLUS clindamycin PLUS debridement.

C. tetani: see tetanus for details. Human tetanus immune globulin (HTIG) 500 IU. Active immunization must also be initiated; getting tetanus does not lead to immunity. Metronidazole preferred, penicillin, imipenem but only metronidazole has been shown to help. Treat with muscle relaxants especially diazepam; the cause of death is autonomic dysfunction.


Clostridium are often part of mixed infections or an unimportant bacteremia in a stable patient. The trick is deciding when it is important and when it is not. That is why there are ID doctors, he says in a self serving note.

Curious Cases

Relevant links to my Medscape blog

It's a gas.

Top Ramosus

I'm Baaaaaaaaaaaaak.

Classical Gas. Gangrene.

Don't Pass on the Gas.

Then Another

A Great Idea

Scary Bug

Not Enough Time

Double Vision

Pulling the Plug

Bowel to Aorta or Aorta to Bowel?

Something Evil Must Be Going On

Sometimes Catastrophic, Sometimes Mostly Harmless

Odd Typhlitis

Always Ask Why

Last Update: 05/03/18.