Capstone assignment on
Associates degree in Medical Technology
96-year-old female was admitted to the hospital with complaint of generalized weakness and diarrhea. She described persistent diarrhea without blood for two weeks as well as fever, body ache and chills. Patients’ past history revealed she was relatively healthy with a previous history of cholesterol management with medication and medications for back pain. Blood Pressure on arrival was within normal limits. Initial lab work was ordered at 17:37 and the CBC revealed an elevated white blood cell count of 13.4 (4.8-10.8%) with a differential that showed an elevated neutrophil count of 82.4% (45.0- 75.0%), 16.0 % lymphocytes (15.0-45.0%), 0.8% monocytes (1.0-10.0%), 0.4% eosinophils (0.0-5.0%), and 0.4% basophils (0.0-3.0%). Her CBC also showed a slightly decreased red blood cell count of 4.09 mill/cmm (4.20-5.40 mill/cmm) with a hemoglobin and hematocrit within normal limits. Red blood cell indices were also normal. CMP revealed elevated total bilirubin 1.5 mg/dl (0.10-1.20 mg/dl), alkaline phosphatase 145 IU/L (39-136 IU/L), AST 182 IU/L (8-46 IU/L), and elevated ALT 262 (12-78 IU/L). The patient had an elevated heart rate and temperature of 101.5 degrees Fahrenheit indicating a positive sepsis screen although her Lactic acid was within normal limits at 1.3 mmol/L (0.4-2.0 mmol/L). Patient was started on the broad-spectrum antibiotics Fortaz. Blood cultures were collected.
The following morning labs were collected and received into the laboratory at 03:00. After centrifugation the tech noticed the tubes did not appear as though they had been spun. With further investigation the tech realized the patient’s specimens were grossly hemolyzed. The patients CBC now indicated a variety of suspect flags and system flags. There was a rapid change from the previous evenings CBC results. The following are comparison tables showing the initial CBC results with the first morning results:
Table 1: Initial evening results. Red values indicate abnormal results.
Table 2: Morning CBC results indicating sudden change in patient condition. Red values indicate abnormal results.
4.8-10.8 (10^3/uL) 4.20-5.40 (10^6/uL)
4.8-10.8 (10^3/uL) 4.20-5.40 (10^6/uL) 12.0-16.0 (g/dL) 36.0-47.0 (%)
81-99 (fL) 27.0-33.0 (pg) 32.0-36.0 (g/dL) 11.6-15.6 (%) 150-400 (10^3/uL) 45.0-75.0 (%) 15.0-45.0 (%) 1.0-10.0 (%) 0.0-5.0 (%)
81-99 (fL) 27.0-33.0 32.0-36.0 11.6-15.6
150-400 (10^3/uL) 45.0-75.0 (%) 15.0-45.0 (%) 1.0-10.0 (%) 0.0-5.0 (%)
(pg) (g/dL) (%)
A slide review was done, and massive intravascular hemolysis was observed. The peripheral smear showed a severe decrease in RBCs, with the presence of spherocytosis, toxic vacuolization, polychromasia with basophilic stippling, immature RBCs, erythrophagocytosis, and immature neutrophils. Images of the patient’s peripheral smear are shown below. The house supervisor was notified of these results. Later than morning, the patient’s blood cultures alarmed indicating growth in the anaerobic bottles. A preliminary gram stain revealed large gram-positive bacilli. Anaerobic culture results revealed the organism as Clostridium perfringens.
Following this exercise, the reader will be able to describe
Microbiology chemical nature
Student Learning Outcome (SLO)
Following this exercise, the reader will be able to compile an accurate diagnosis and treatment
Clostridium perfringens by its
Following this exercise, the reader will be able to list the 6 different Major types of Clostridium
perfringens based on toxins
plan for a patient with Clostridium perfringens
Following this exercise, the reader will be able to evaluate transmission of Clostridium
Following this exercise, the reader will be able to classify the complications that can occur from
a Clostridium perfringens infection.
Clostridium perfringens was first discovered in 1892 by George Nuttall and William Welch which is why it was originally named Clostridium welchii. Clostridium perfringens is an anaerobic, Gram-positive, rod-shaped, encapsulated pathogenic bacterium of the genus Clostridium. Clostridium perfringens is typically found in the soil, raw meat and poultry, in the intestines of certain animals, but is also often found as part of the intestinal normal flora and sometimes in the vaginal flora. Clostridium perfringens is one of the most common causes of food poisoning in the United States and infections due to C. perfringens can lead to types of tissue necrosis, septicemia and diseases such as enterocolitis and gas gangrene. Immunosuppression, malignancy and diabetes are the most common risk factors for developing complications induced by C. perfringens. The most common vehicle for transmission is
undercooked beef, followed by poultry since clostridium perfringens is not transmitted from person to person; it is not as contagious as other clostridium species like clostridium difficile.Clostridium perfringens has 6 major different toxins that cause all types of infections and diseases.  The major toxins involved in diseases are alpha (CPA), beta (CPB), epsilon (ETX), iota (ITX), enterotoxin (CPE), and necrotic B-like (NetB) toxins. While the alpha toxin and enterotoxin are known to cause human disease each of the toxins can lead to a different pathology in humans and animals. All types of Clostridium perfringens produce alpha toxin which has been reported to hydrolyze phospholipids in red blood cell membranes, leading to massive hemolysis and severe tissue hypoxia due to the failure of oxygen transport function restricting blood flow towards the area of infection producing an anaerobic environment essential for the proliferation of the bacteria. Alpha toxin causes food poisoning and the disease gas gangrene, which is the most common infection with Clostridium perfringens, it affects deep muscle tissue where gas is released causing tissue death and can be very life-threatening. Beta toxin is responsible for the disease  Pigbel which is a form of acute,segmental, necrotizing enteritis presenting as a common and life-threatening disease among the people of the highlands of Papua New Guinea. The epsilon toxin plays an important role in the disease enterotoxemia in sheep and goats and recently has been associated with development of Multiple sclerosis in humans as they have been shown to have antibodies to the epsilon toxin of Clostridium perfringens. The iota toxin and its enzymatic activity destroys normal cell functions and is responsible for diseases in animals implicated in some diarrheic outbreaks among calves and lambs. Enterotoxin produced by Clostridium perfringens is responsible for causing the gastrointestinal symptoms of several food- and nonfood-borne human gastrointestinal diseases. NetB is a pore-forming toxin identified in avian necrotic enteritis but so far has not been linked to pathogenicity in humans. Diagnosis of Clostridium perfringens is somewhat difficult as it is not a routine test for clinical laboratories and needs to be specially ordered by the physician if they suspect it to be the cause of infection. Physicians will notice that the patient presents with hemolysis increased levels of indirect bilirubin, LDH and anemia are indications for further testing but if gross hemolysis is noticed immediate action needs to be taken as that could lead to death. Clostridium perfringens can be diagnosed or confirmed by detection of the bacteria and/or toxin in a stool culture or by PCR methods, stool studies will also include WBCs, ova, and parasites to help rule out other etiologies.
The Alpha toxin produced by Clostridium perfringens is the most lethal of the toxins and can cause intravascular hemolysis in patients if untreated. Intravascular hemolysis is the rupture or lysis of RBC within the circulation in vivo (in a living system). When the membrane of erythrocytes rupture, they release their hemoglobin into the plasma and will cause visible discoloration of plasma causing it to appear red or pink, as we seen in the case study. There was a rapid change in the patient blood results from the initial blood draw until the 3:00am draw as the deterioration of the body systems is fast and we see that with the red blood cell (RBC) / hemoglobin (Hb) discrepancy and by the hemolysis, in the presence of infection should prompt the physicians to consider clostridium perfringens septicemia to act quickly to provide appropriate treatment because of the severity of the disease. The patient in the case study had a peripheral smear done which was indicative of intravascular hemolysis as it showed a
decrease in mature RBCs and an increase with immature RBCs with toxic vacuolization, also a great indicator of an infection in the blood. Clostridium perfringens can also lead to sepsis in your blood which is a life-threatening complication of an infection, chemicals released in the bloodstream to fight the infection trigger inflammation throughout the body and not only fight the infection but can trigger a response throughout the body causing inflammation and changes that can damage multiple organ systems. Sepsis has symptoms that include fever, difficulty breathing, low blood pressure, and a fast heart rate which is how our patient presented in the case study. Clostridium perfringens septicemia is rare due to CPA-mediated destruction of red blood cells but typically proves rapidly fatal in this situation early antibiotic treatment would be essential. Our Patient had Blood cultures done to confirm a blood infection and the next morning it grew Clostridium perfringens. Once the organism is identified we can now proceed with treatment although the patient was started on broad spectrum antibiotics, we can now narrow the antibiotics to what is needed. Infection with C perfringens is probably the most serious condition, and treatment should be started as soon as suspicion arises. You treat C. perfringens by managing any complications until it passes, dehydration caused by diarrhea and vomiting is the most common complication. C. perfringens strains are generally sensitive to a variety of antibiotics, such as penicillins, cephalosporins, carbapenems, clindamycin, metronidazole and vancomycin. Benzylpenicillin has been listed as the first choice.However, there is experimental data indicating that clindamycin and metronidazole, among others, may reduce alpha toxin activity more rapidly. You can prevent Clostridium perfringens food poisoning by cooling and storing foods correctly, use a clean meat thermometer to determine whether foods are cooked to a safe temperature, and finally When in doubt, throw it out and never take the chance with your body.
This patient presented with persistent GI symptoms. She did have some indicators of sepsis, but the severity was not apparent. Her Lactic acid results on arrival were within normal limits and her initial CBC was relatively unremarkable with the presence of neutrophilia and slightly anemia. In time span of less than 12 hours the patient’s condition deteriorated rapidly. The C. perfringens bacteria rapidly proliferated causing massive intravascular hemolysis which lead to the patient’s death only a few hours after her specimens were received in the lab the lab the morning after her arrival. Unfortunately, because of the patient’s age an autopsy was not performed, and the exact source of the Clostridium perfringens infection was not determined. Because of her GI symptoms, it is hypothesized that the patient suffered from enteritis for a couple of weeks and eventually the bacteria caused a perforation in her bowel that led to large numbers of bacteria entering her blood stream. This large amount of bacteria produced high amount of toxins that caused severe and rapid damage to her RBCs and the patient was unable to recover. Clostridium perfringens produces many different toxins that enhance the virulence of this organism depending on the type and source of the infection. It is important to understand the way this organism causes disease and how to recognize this organism so that rapid detection and prompt treatment can prevent deterioration of patient condition to the point where treatment is ineffective.
1. Navarro, Mauricio A et al. “Mechanisms of Action and Cell Death Associated with Clostridium perfringens Toxins.” Toxins vol. 10,5 212. 22 May. 2018, doi:10.3390/toxins10050212.
2. Cooke RA. Pig Bel. Perspect Pediatr Pathol. 1979;5:137-52. PMID: 575409
3. Stevens DL, Maier KA, Mitten JE. Effect of antibiotics on toxin production and viability of
Clostridium perfringens. Antimicrob Agents Chemother. 1987; 31 (2): 213-8.
4. Sakaue, M., Ota, K., Nakamura, E. et al. Type A fulminant Clostridium perfringens sepsis
indicated RBC/Hb discrepancy; a case report. BMC Infect Dis 19, 719 (2019).
5. Julian I. Rood, Vicki Adams, Jake Lacey, Dena Lyras, Bruce A. McClane, Stephen B. Melville,
Robert J. Moore, Michel R. Popoff, Mahfuzur R. Sarker, J. Glenn Songer, Francisco A. Uzal, Filip Van Immerseel,Expansion of the Clostridium perfringens toxin-based typing scheme,Anaerobe,Volume 53,2018,Pages 5-10,ISSN 1075-9964,
6. Francisco A Uzal, John C Freedman, Archana Shrestha, James R Theoret, Jorge Garcia, Milena M Awad, Vicki Adams, Robert J Moore, Julian I Rood, Bruce A McClane Future Microbiol. Author manuscript; available in PMC 2015 Jan 1. Published in final edited form as: Future Microbiol. 2014; 9(3): 361–377. doi: 10.2217/fmb.13.168, PMCID: PMC4155746
7. Content source: Centers for Disease Control and Prevention, National Center for Emerging and Zoonotic Infectious Diseases (NCEZID), Division of Foodborne, Waterborne, and Environmental Diseases (DFWED)
8. Success! In clinical laboratory science: complete review/[edited by] Anna P. Ciulla, Donald C. Lehman. —4th ed.p; cm. Rev. ed of: Prentice Hall health’s Q and A review of medical technology/clinical laboratory science/ Anna P. Ciulla, Georganne K. Buescher [editors]. 3rd ed. C2002. Includes bibliographical references and index. ISBN-13: 978-0-13-512628-6
9. Wagley S, Bokori-Brown M, Morcrette H, Malaspina A, D’Arcy C, Gnanapavan S, Lewis N, Popoff MR, Raciborska D, Nicholas R, Turner B, Titball RW. Evidence of Clostridium perfringens epsilon toxin associated with multiple sclerosis. Mult Scler. 2019 Apr;25(5):653-660. doi: 10.1177/1352458518767327. Epub 2018 Apr 21. PMID: 29681209; PMCID: PMC6439943
When and for how long is a person able to spread the disease?
C. perfringens is not spread person-to-person.
Even after the infection
What is the morphology and cultural characteristics of Clostridium perfringens?
Gram Positive bacilli, grows anaerobically
Gram negative bacilli, grows aerobically
Gram positive cocci grows anaerobically
Gram negative cocci grows aerobically
How Can You Diagnose Clostridium perfringens?
laboratory test detects the bacteria or the toxin in a stool sample
Palpation of the stomach
No test to confirm
What are some complications that can occur from a C. perfringens infection?
A 35-year-old man is brought to the hospital a few days after a biking accident. He is found to
have multiple fractures with open wounds in the leg. His vital signs show low blood press