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Clostridial Intra-Abdominal and Pelvic Infections


Larry M. Bush

, MD, FACP, Charles E. Schmidt College of Medicine, Florida Atlantic University;

Maria T. Vazquez-Pertejo

, MD, FACP, Wellington Regional Medical Center

Reviewed/Revised Jun 2023

Clostridia, primarily Clostridium perfringens, are common in mixed intra-abdominal infections Mixed Anaerobic Infections Anaerobes can infect normal hosts and hosts with compromised resistance or damaged tissues. Anaerobic infections can include both single anaerobic species or multiple anaerobic species with... read more resulting from a ruptured viscus or pelvic inflammatory disease. Symptoms of abdominal infection may include fever, pain, and tenderness; symptoms of pelvic infection may include a foul-smelling discharge. Diagnosis is by Gram stain and culture. Treatment is with penicillin and surgical debridement.

Clostridial infections of the abdomen and pelvis are serious and sometimes fatal.

Clostridium species are common residents of the gastrointestinal tract and are present in many abdominal infections, generally mixed with other enteric organisms. Clostridia are often the primary agents in the following:

  • Emphysematous cholecystitis

  • Gas gangrene of the uterus (which may occur after delivery and was previously common among patients who had a septic abortion)

  • Certain other female genital tract infections (tubo-ovarian, pelvic, and uterine abscesses)

  • Infection after perforation in colon carcinoma

The primary organisms are C. perfringens and, in the case of colon carcinoma, C. septicum. Clostridia produce exotoxins (lecithinases, hemolysins, collagenases, proteases, lipases) that can cause necrosis. Gas formation is common. Clostridial septicemia may cause hemolytic anemia because lecithinase (alpha-toxin) disrupts red blood cell membranes. With severe hemolysis, muscle necrosis, and coexisting toxicity, acute renal failure can occur.

Symptoms and Signs

Symptoms of clostridial infections are similar to those of other abdominal infections (eg, pain, fever, abdominal tenderness, a toxic appearance). Patients with a uterine infection may have a foul-smelling, bloody vaginal discharge, and gas sometimes escapes through the cervix. Rarely, acute tubular necrosis develops.


Sepsis may be a complication of intra-abdominal or uterine clostridial infections. Initial symptoms can include fever, chills, vomiting, diarrhea, abdominal pain, hypotension, tachycardia, jaundice, cyanosis, and oliguria.

In 7 to 15% of patients with sepsis due to C. perfringens, acute massive intravascular hemolysis occurs. These patients have jaundice and red-tinged serum and urine. Spherocytes, ghost cells, and sometimes C. perfringens can be seen in a stained blood smear. Blood cultures are positive for C. perfringens.

Clostridial sepsis may result in multiorgan failure, which is frequently fatal, often within 24 hours of hospital admission.


  • Gram stain and culture

Early diagnosis of clostridial infections requires a high index of suspicion. Early and repeated Gram stains and cultures of the site, pus, lochia, and blood are indicated. Gram stain of the wound discharge shows gram-positive rods; polymorphonuclear cells are absent because of destruction by alpha-toxin.

Because C. perfringens can occasionally be isolated from healthy vagina and lochia, cultures are not specific.

X-rays may show local gas production (eg, in the biliary tree, gallbladder wall, or uterus).


  • Surgical debridement

  • High-dose penicillin (or carbapenems, beta-lactam/beta-lactamase inhibitors, metronidazole, or clindamycin)

Treatment of clostridial abdominal and pelvic infections is surgical debridement and penicillin G 5 million units IV every 6 hours for at least 1 week. Alternatively, carbapenems Carbapenems Carbapenems include Ertapenem Imipenem Meropenem Carbapenems are parenteral bactericidal beta-lactam antibiotics that have an extremely broad spectrum. They are active against read more , beta-lactam/beta-lactamase inhibitors (eg, piperacillin/tazobactam) metronidazole, or clindamycin may be used. Clindamycin is often used in combination with penicillin because clindamycin has the ability to suppress toxin production. When polymicrobial anaerobic infection is a concern, a carbapenem or a beta-lactam/beta-lactamase inhibitor combination is used. Organ removal (eg, hysterectomy) may be necessary and can be lifesaving if debridement is insufficient.

The usefulness of hyperbaric oxygen has not been established.

Key Points

  • Clostridial intra-abdominal and pelvic infections are serious and sometimes fatal.

  • Like other abdominal infections, clostridial abdominal infections cause pain, fever, and abdominal tenderness, and patients have a toxic appearance.

  • Patients with a clostridial uterine infection may have a foul-smelling, bloody vaginal discharge; gas sometimes escapes through the cervix.

  • Early diagnosis of clostridial infections requires a high index of suspicion and early and repeated Gram staining and cultures of the samples from the site and samples of pus, lochia, and blood.

  • Treat with surgical debridement and high-dose penicillin or other antibiotics (carbapenems, beta-lactam/beta-lactamase inhibitors, metronidazole, clindamycin).

Drugs Mentioned In This Article

Drug Name Select Trade
Zosyn, Zosyn Powder
Flagyl, Flagyl ER, Flagyl RTU, LIKMEZ, MetroCream, MetroGel, MetroGel Vaginal, MetroLotion, Noritate, NUVESSA, Nydamax, Rosadan, Rozex, Vandazole, Vitazol
Cleocin, Cleocin Ovules, Cleocin Pediatric, Cleocin T, CLIN, Clindacin ETZ, Clindacin-P, Clinda-Derm , Clindagel, ClindaMax, ClindaReach, Clindesse, Clindets, Evoclin, PledgaClin, XACIATO
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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