CLOSTRIDIUM SEPTICUM: CHARACTERISTICS, MORPHOLOGY, SYMPTOMS - BIOLOGY - 2025

Clostridium septicum is a pathogenic sporulated anaerobic bacterium of mainly veterinary importance that rarely affects humans. This microorganism is among the 13 most virulent species of Clostridia and is classified within the cytotoxic clostridia, being highly resistant to adverse conditions due to the formation of spores.

The spores are widely distributed in nature, especially they are found in soils rich in organic matter. In Veterinary Medicine, C. septicum is included among the causative agents of soil-associated diseases.

Clostridium septicum

Clostridium septicum is a pathogenic and virulent species, but it does not have invasive power on healthy tissues. Therefore, the infection occurs in a similar way to other clostridia, such as C. chauvoei, C. tetani or C. perfringens; by contamination of a wound with spores of the microorganism.

The wound functions as a gateway; this is how the spore enters the tissue. Wounds from shearing, peeling, castration or injection of veterinary products are the main causes of contamination with the spore in animals.

The microorganism needs a trigger that provides optimal conditions of low oxygen tension in the tissues.

In this way, the microorganism is able to germinate to the vegetative form and reproduce in appreciable quantity to produce the toxins that are ultimately responsible for the disease.

The infection is of rapid course, the microorganism affects the subcutaneous and muscular tissue, then septicemia, toxic-infectious shock and death of the animal occur.

Gas gangrene or necrotizing fasciitis in humans

It is less frequent and most of the time it is caused by the perfringens species.

However, when C. septicum is present, it is due to serious infections with high mortality associated with underlying malignant processes such as colon or cecum carcinoma, breast carcinoma, and hematological malignancies (leukemia-lymphoma).

Since C. septicum can form part of the intestinal microbiota of 2% of the population, if there is a tumor or metastasis at this level, a disruption of the mucosal barrier occurs, allowing the hematogenous invasion of the bacteria.

The neoplastic process itself generates an environment of hypoxia and acidosis from the anaerobic tumor glycolysis, favoring the germination of the spore and progression of the disease.

Other risk factors are surgical procedures such as endoscopies, irradiation or barium enema among others.

Clinical manifestations

After the surgical maneuver in the animal, if the wound becomes contaminated, some symptoms can be observed in 12 to 48 hours. The wound is usually swollen with tight skin.

The behavior of the animal is not normal, it becomes depressed, has pain in the affected area and fever. There is almost never an opportunity to observe these signs, therefore it is not treated in time and the caretaker simply notices when he sees the dead animal.

The diagnosis is generally made post-mortem. At necropsy, a blackish, moist, jelly-like material with a characteristic putrid odor can be seen under the wound skin.

Diagnosis

Culture media and conditions

Clostridia grow well in a laboratory-prepared medium containing thioglycollate broth, cysteine, or peptone, to which pieces of meat, liver, spleen, or brain are added. This medium is known as the Tarozzi medium.

It also grows in media enriched with vitamins, carbohydrates and amino acids. They grow well on blood agar and egg yolk agar.

The media should be neutral in pH (7.0) and incubated at 37 ° C for 1 to 2 days.

The culture media should be placed in an anaerobic jar. The seeded media with a commercial envelope (GasPak) is placed inside the jar.

This envelope catalytically reduces oxygen by hydrogen generated along with carbon dioxide.

Biochemical tests

Negative tests

Lecithinase, lipase, urease, catalase, indole, fermentation of mannitol, rhamnose and sucrose.

Positive tests

Milk coagulation, fermentation of glucose, maltose, salicin, glycerol, motility. Produces acetic and butyric acid.

Tests with variable result +/-:

Hydrolysis of gelatin, hydrolysis of esculin and fermentation of lactose.

There are semi-automated and automated methods for the identification of clostridial species. Among them we can mention: Api 20 A®, Minitek®, Rapid ID 32 A®, Anaerobe ANI Card®, Rapid Anaerobe ID®, RapID-ANA® or Crystal Anaerobe ID®.

Treatment

Clostridium septicum is sensitive to a wide variety of antibiotics.

Among them:

Ampicillin / sulbactam, cefoperazone, cefotaxime, cefotetan, cefoxitin, ceftriaxone, chloramphenicol, clindamycin, imipenem, metronidazole, penicillin G, piperacillin / tazobactam, ticarcillin / ac. clavulanate, Amoxicillin / ac. clavulanic.

However, there is almost never an opportunity for its administration and when it is achieved the toxin has wreaked havoc and the affected individual dies irremediably.

Prevention

A commercially available vaccine called Polibascol 10 (1 mL of injectable suspension for cattle and sheep), which protects against clostridial diseases.

It has a good immune response, providing an active immunization that can last 6 months in the case of prevention against C. septicum and up to 12 months for other clostridia.

The vaccine contains:

• Toxoid (alpha) of C. perfringens Type A
• Toxoid (Beta) of C. perfringens Type B and C
• Toxoid (Epsilon) of C. perfringens Type D
• Complete culture of C. chauvoei
• Toxoid C. novyi
• Toxoid C. septicum
• C. tetani toxoid
• Toxoid C. sordellii
• C. haemolyticum toxoid
• Adjuvant: Aluminum potassium sulfate (alum)
• Excipients: Thiomersal and formaldehyde.

There is no vaccine for humans.

Contraindicated in: sick or immunosuppressed animals.

References

1. Cesar D. Clostridial Diseases. Animal health and welfare. Pp 48-52
2. Polibascol vaccine technical data sheet 10-1939 ESP-F-DMV-01-03. Ministry of Health, Social Services and Equality. Spanish Agency for Medicines and Health Products. Veterinary Medicines Department. pp 1-6
3. Elía-Guedea, M, Córdoba-Díaz E, Echazarreta-Gallego E and Ramírez-Rodríguez J. Clostridial necrotizing fasciitis associated with perforated colonic neoplasia: importance of an early diagnosis. Rev. Chil Cir. 2017; 69 (2): 167-170
4. Ortiz D. Isolation and molecular characterization of clostridia associated with the soil in cattle areas of Colombia with mortality problems in cattle. Degree work to qualify for the title of Doctor of Science-Animal Health. 2012, National University of Colombia, Faculty of Veterinary Medicine and Zootechnics.
5. Koneman E, Allen S, Janda W, Schreckenberger P, Winn W. (2004). Microbiological Diagnosis. (5th ed.). Argentina, Editorial Panamericana SA
6. Arteta-Bulos R, Karinm S. Images in clinical medicine. Non traumatic Clostridium septicum myonecrosis. N Engl J Med. 2004; 351: e15
7. Gagniere J, Raisch J, Veziant J, Barnich N, Bonnet R, Buc E, et al. Gut microbiota imbalance and colorectal cancer. World J Gastroenterol. 2016; 22 (1): 501-518
8. Carron P, Tagan D. Fulminant spontaneous Clostridium septicum gas gangrene. Ann Chir. 2003; 128 (1): 391-393