CRONOBACTER SAKAZAKII: CHARACTERISTICS, DISEASES - MEDICINE - 2025

Cronobacter sakazakii is a bacterium of the family of Enterobacteriaceae, capable of causing diseases in humans. Formerly known as Enterobacter sakazakii, its presence in the body has been related to cases of meningitis and gastroenteritis, especially in pediatric patients, although it can affect all age groups.

The etymology of the word cronobacter is very interesting. It comes from the Greek kronos, a titan of mythology, famous for having eaten each of his children at birth for fear of a prophecy that said that one of them would take away his power; the predilection of this bacterium for children gave it its name. Bacter is a suffix for any bacteria.

Unfortunately notorious for its occasional presence in infant formula, it has been responsible for several outbreaks of infection in infants and newborns admitted to neonatal intensive care units. This relationship was verified through the scientific method and the statistical association was significant.

Infection with this bacterium causes very nonspecific gastrointestinal symptoms in children. If not treated in time and with the ideal medications, the infection can progress to septic symptoms or meningitis, especially in preterm and immunocompromised neonates or infants.

Biological characteristics

Cronobacter sakazakii is a non-spore-forming gram-negative rod, facultative anaerobic, oxidase negative and catalase positive, belonging to the family of Enterobacteriaceae. This bacterium has lateral flagella that provide mobility. It was described in 2007 by the Japanese microbiologist Riichi Sakazaki; hence its name.

Its most important characteristic is the ability to form a polysaccharide capsule that helps it resist drying out and protects it against disinfecting agents.

In addition, this gives it the property of easily adhering to materials such as plastic, silicone, polycarbonate, glass and stainless steel, all used in food manufacturing.

Despite being inactivated by pasteurization and at temperatures above 70 ºC, its structural characteristics allow it to survive in dry environments, hence its ability to remain in the powder of infant formulas. It can also be found in tea bags, dried or dehydrated foods, and even sewage.

Diseases it produces

Cronobacter sakazakii has been implicated in severe infections in pediatric patients. Although it may also affect adults, cases in this age group are mild. The elderly and immunosuppressed patients can occasionally suffer serious illnesses caused by this germ.

Diseases caused by this bacteria include the following:

Central nervous system infections

Cronobacter sakazakii infections can cause meningitis, cerebritis, or encephalitis in vulnerable populations.

Necrotizing enterocolitis

Exclusive disease of newborns and infants. It occurs when bacteria lodge in the host's gastrointestinal tract.

Septicemia

Systemic and bloodstream infections are common in susceptible patients, especially premature and immunocompromised babies.

Symptoms

The severity of the symptoms will depend on the affected age group, immune status and affected system.

In pediatrics

In newborns and infants who have consumed contaminated milk formulas, the symptoms are more serious. The first signs of illness may be nonspecific, such as fever, inconsolable crying, loss of appetite, and irritability. After 72 hours from the onset of the condition, it tends to worsen and is considered sepsis.

In central nervous system infections, the first sign of severity is seizure. Sometimes they are difficult to diagnose because they are not usually tonic-clonic as in adults.

Babies become clouded, the fontanel is bulging and tense, the comatose state appears, and if it is not treated, death or catastrophic sequelae.

Necrotizing enterocolitis is a spectacular picture. It begins with rejection of food and vomiting without nausea. Then there is fever, bloating and intestinal loops are drawn through the abdominal wall; baby looks toxic with earthy skin discoloration. Eventually the intestines are perforated and the risk of death is high, even with surgery.

In adults

Most adults have mild or moderate symptoms that do not require intensive treatment. Oral antibiotics are sufficient. Problems occur in elderly or immunocompromised patients, in whom infections are serious and life-threatening.

Infections in these patients can affect the gastrointestinal, urinary, nervous, and skin systems. The most common symptoms are fever, diarrhea, abdominal pain, dysuria, vomiting, headache, dizziness, seizures, and coma. It is also possible to find skin lesions that serve as a gateway for the bacteria.

Septicemia is the most feared condition in adults. Infection of the blood promotes the seeding of the germ in any region of the body and can lead to a clinical picture that is difficult to manage. Septic patients present multiorgan failure with kidney, liver and respiratory failure with a high risk of fatal consequences.

Treatments

Treatment of the condition will be based on the severity of the disease and the systems affected. All patients with severe Cronobacter sakazakii infections should be hospitalized and permanently monitored. Therapeutic management of the disease includes:

Antibiotics

The combination of ampicillin and gentamicin has shown positive results as an antimicrobial treatment against Cronobacter sakazakii.

However, the emergence of strains resistant to these antibiotics has forced doctors to use cephalosporins of newer generations and a greater spectrum, as well as other aminoglycosides or carbapenems.

Support measures

The majority of hospitalized patients do not tolerate the oral route, so they must receive parenteral nutrition and hydration. Gastric protectors and antiemetics are also indicated to relieve gastrointestinal discomfort. Severely ill and septic patients may require assisted ventilation and continuous review.

Prevention

Prophylaxis is essential to avoid infection with Cronobacter sakazakii. Due to all the epidemiological antecedents concerning this bacterium, WHO and FAO have published several recommendations for the manufacturers of infant milk formulas and, more importantly, for their preparation.

Among the most important suggestions made by these entities are the following:

- Prepare the infant formula with water above 70 ° C.

- Do not prepare the formulas in advance, to minimize storage time.

- If it is necessary to store the milk, do so in refrigerators with a temperature below 5 ° C.

References

1. World Health Organization (2004). Enterobacter sakazakii and other microorganisms in powdered infant formula. Microbiological Risk Assessment Series. Recovered from: who.int
2. Center for Disease Control and Prevention (2017). Learn about Cronobacter. Recovered from: cdc.gov
3. Chenu, JW and Cox, JM (2009). Cronobacter ('Enterobacter sakazakii'): current status and future prospects. Letters in Applied Microbiology, 49 (2009): 153-159.
4. Fei, Peng et al. (2017). Antibiotic and Desiccation Resistance of Cronobacter sakazakii and C. malonaticus Isolates from Powdered Infant Formula and Processing Environments. Frontiers in Microbiology, 8: 316.
5. Kilonzo-Nthenge, A. et al. (2012). Prevalence and Antimicrobial Resistance of Cronobacter sakazakii Isolated from Domestic Kitchens in Middle Tennessee, United States. Journal of Food Protection, 75 (8): 1512-1517.
6. Luján Medina, Gabriel; Loredo Treviño, Araceli and Noe Aguilar, Cristóbal (2014). Cronobacter sakazakii: An Emerging Foodborne Pathogen. Acta Química Mexicana, 6 (12).
7. Argentine Society of Pediatrics (2015). Cronobacter sakazakii contamination of milk. Recovered from: sap.org.ar
8. Parra F., Julio and collaborators (2015). Risk of contamination by Cronobacter Sakazakii in powdered milk for infant nutrition. Chilean Journal of Nutrition, 42 (1).
9. Wikipedia (2018). Cronobacter sakazakii. Recovered from: en.wikipedia.org