How to Treat Eikenella corrodens Bacteria in Human Bites on Face, hands, and Legs (oral and non-oral infections)

Many are bitten by animals, and the bite can cause a minor wound, but it can be accompanied by serious complications. One of the most serious complications of bites is rabies, or rabies. So you should know what to do when bitten.

Studies have revealed that the human bite is the second most common bite in emergency rooms, and it may be more dangerous than the bite of some predators, and the reason for this is due to the types of bacteria and viruses present in the human mouth. The human mouth contains millions of microbes that coexist inside the mouth between the teeth and gum pockets, and turn into harmful microbes by transferring them to other tissues through biting.

The most common pathogens associated with bite wounds are Streptococcus species, Staphylococcus species, Pasteurella multocida, Capnocytophaga canimorsus and anaerobic bacteria.

Sporadically other pathogens are isolated from bite wounds. Human bites differ from animal bites by higher prevalence of Staphylococcus aureus and Eikenella corrodens.

Infected human bites yield a similar spectrum of bacteria except for Pasteurellae and C. canimorsus; instead human bites are frequently complicated by Eikenella corrodens. When does the Allergic Reaction Appear?

What is the definition of Eikenella corrodens?

Eikenella corrodens is a Gram-negative facultative anaerobic bacillus that can cause severe invasive disease in humans.

E. corrodens is a rare pericarditis associated pathogen.

It is a fastidious, slow growing, human commensal bacillus, capable of acting as an opportunistic pathogen and causing abscesses in several anatomical sites, including the liver, lung, spleen, and submandibular region.

E. corrodens could independently cause serious infection in both immunocompetent and immunocompromised hosts

Eikenella corrodens, a gram negative rod, was cultured in about one third of 24 patients with human bite wounds. The organism was sensitive to penicillin but not to methicillin. Clinically the infections in which Eikenella corrodens were found were not different from other infections.

Most of patients in this series required surgical drainage. Surgical treatment consists of thorough exploration, exteriorization and excision of devitalized tissues. Complications were more frequent in sutured wounds, or when surgical drainage was delayed.

Animal Bite wounds

Animal Bites human dogs cats rats mice bats

Different from Mosquito bites or any insect stings

Human bites: Children are more susceptible to this type of bite, as a result of playing with an aggressive child. The bite is semi-circular, or oval, and red. It may leave bruises or holes in the place of the teeth. These bites are often on the face, upper extremities, or trunk.

Dog bites: often happen to children, and the most famous places for bites are the head and neck. In adults, the places of bites are often in the arms and legs, especially the right hand. Injuries range from scrapes, deep open wounds, and lacerations, and dog bites rarely lead to death.

are frequently located on the face; injuries inflicted by dogs are most common, especially in children. Bacteriology of infected dog and cat bite wounds includes Pasteurella multocida, Staphylococcus aureus, viridans streptococci, Capnocytophaga canimorsus, and oral anaerobes.

Cats injury: is often to the upper extremities, such as: the arms, hands, or the face. Deep wounds are a concern; Because cats have long and sharp teeth; So it is possible for bacteria to reach the bone, or joint, leading to inflammation. If infection occurs, it causes redness, swelling, and severe pain as quickly as 12 to 24 hours after the bite.

Rodent bites: The most famous of these are mice, and bites occur at night, often on the hands or face.

Antibiotic therapy against E. corrodens bacteria

It is indicated both for infected bite wounds and fresh wounds considered at risk for infection.

E. corrodens infections of the head and neck occur most frequently in the tonsil even in hosts with normal immunity. Coexistence with Streptococcus milleri group bacteria and the use of ineffective antibiotics can be exacerbating factors. First-choice drugs for E. corrodens infections should be third-generation cephems, carbapenems, or new quinolones.

Amoxicillin-clavulanate (and other combinations of extended-spectrum penicillins with beta-lactamase inhibitors) and moxifloxacin offer the best in vitro coverage of the pathogenic flora. Initial wound management consisting in irrigation and debridement is at least equally important with antibiotics for prevention of infection.

Successful antibiotic therapy

It can be achieved with benzylpenicillin or ampicillin which are the drugs of choice. E. corrodens is a slow growing bacterium of low virulence, rarely isolated in current practice because of its unusual association with conditions such as human bites, infections of the oral cavity or immuno-suppressive therapy.

The lifetime risk of experiencing a bite wound, human or animal, is approximately 50%, and bite wounds account for approximately 1% of all visits to emergency departments. The majority of bite wounds are inflicted by dogs and cats.

The need for prophylaxis against systemic infectious complications

particularly tetanus, should also be evaluated. Primary surgical repair is the treatment of choice for most clinically uninfected facial bite wounds, whereas delayed closure should be reserved for certain high risk or already infected wounds.

It is important to be aware of the possibility of complicating infections following bite wounds, particularly after cat bites.

Clinicians must have a high index of suspicion when evaluating any hand injury and clenched fist injuries of the hand should be treated by early adequate surgical debridement followed by IV penicillin given until operative cultures confirm or deny contamination with Eikenella corrodens.

Treatment of infections associated with cat and dog bites

Phenoxymethyl penicillin should be the drug of choice in treatment of infections associated with cat and dog bites. However, in case of slow recovery or no improvement, simultaneous lymphadenopathy or pneumonia, S. aureus or Francisella tularensis should be suspected; ciprofloxacin is recommended. For human bite infections the recommend treatment is phenoxymethyl penicillin in combination with penicillinase-stable penicillin.

Avulsive injuries with significant tissue loss represent the most difficult cases for definitive management and are also those most likely to require hospitalization.

a prospective study with serial aerobic, anaerobic, and 10% CO(2) cultures is needed to confirm these findings. Lack of organization in management was the most notable finding. Inpatient therapy with intravenous antibiotics usually is required. Treatment should revolve around the mnemonic ‘ODD BITES’: open treatment; debridement; drugs (antibiotics); bloodwork (leukocyte count); irrigation; tetanus prophylaxis; exploration (including X-rays); and swab (for culture and sensitivity).

Contaminated injuries

It is estimated that 250,000 human bites occur each year in the United States, mostly in children. Up to 25% of these infections are contaminated, indicating that the most feared diseases are hepatitis B and tetanus.

Although these diseases do not occur with every bite, hepatitis and tetanus may occur, especially in infected bites.

Complications of infection

The bite may cause complications such as infection, permanent disability or even amputation in some cases. The reason to saliva, which contains millions of bacteria that can cause infection, in addition to the hand itself and the microbes it may contain.

Hand bite

Professor Stephen Kennedy of the University of Washington in Seattle stated that “hand bite” in particular needs medical care, and it is necessary to take antibiotics to reduce infection and complications that can occur in 30-50% of cases.

Regarding the bite of children, it is less dangerous than adults, because adults can have gingivitis and the mouth contains more bacteria.


Regarding the measures that should be taken if a person is bitten by a person and penetrates the skin, Stop the bleeding by applying pressure to it using a clean cloth, and then wash the wound with water, apply an antibiotic ointment to prevent infection, and then bandage the affected area with a clean bandage.

It is reported that, according to the medical website “health day”, there is new research that reviewed many previous studies, which revealed the need to receive medical care and go to the doctor in case of a bite that causes the penetration of the teeth embedded in the skin of the hand, whether from a human or an animal, in order to prevent possible complications. .

To care for a human bite that has caused a skin wound

  1. Stop bleeding by applying pressure to the wound with a clean, dry cloth
  2. Wash the wound thoroughly with soap and water
  3. Apply a clean bandage
  4. Cover the injured area with a medical non-adhesive bandage
  5. Seek urgent medical attention

Risk of exposure to rabies:
Everyone who has been bitten by animals such as: raccoon, fox, wolf bat, needs immediate medical attention, even if the injury is minor; Where these animals may be carriers of rabies.

First Aid for Dealing with Animal and Human Bites:

One of common at home remedies, Washing the wound with soap and water; This reduces the incidence of infection.
Provide emergency medical attention such as:

In minor wounds:

  1. Wash the wound carefully.
  2. Apply an antibiotic cream.
  3. Cover the wound with clean gauze.
  4. See the emergency immediately if the wound is red, pain, high body temperature, swelling appears, or if you suspect that the dog was rabid.

In deep wounds:

  1. apply pressure to clean gauze; to stop the bleeding.
  2. When you are unable to stop the bleeding, or if you feel very tired, you should call an ambulance.
  3. Go to the doctor as soon as possible; to examine the wound.

When to see a doctor:

  1. ​When there is severe bleeding that does not stop after pressing on it for 15 minutes, or a feeling of severe pain.
  2. When you notice a rise in body temperature, or when the wound is red, pain, or swelling appears.
  3. If the bite is deep, and it has been five years since the last tetanus vaccination.
  4. If the bite wound is large.
  5. If the patient suffers from diabetes, liver disease, cancer, a weak immune system.