Dr. Solanke Andrew Olusegun

Topic: Tetanus

Tetanus facts– Tetanus is frequently a fatal infectious disease.– Tetanus is caused by a type of bacteria

(Clostridium tetani).– The tetanus bacteria often enter the body

through a puncture wound, which can be caused by nails, splinters, insect bites, burns, any skin break, and injection-drug sites.

– All children and adults should be immunized against tetanus by receiving vaccinations.

– A tetanus booster is needed every 10 years after primary immunization or after a puncture or other skin wound which could provide the tetanus bacteria an opportunity to enter the body.

What is tetanus?

– Tetanus is an acute, often-fatal disease of the nervous system that is caused by nerve toxins produced by the bacteriumClostridium tetani. This bacterium is found throughout the world in the soil and in animal and human intestines.

Where do tetanus bacteria grow in the body?• Contaminated wounds are the sites where tetanus

bacteria multiply. Deep wounds or those with devitalized (dead) tissue are particularly prone to tetanus infection.

• Puncture wounds, such as those caused by nails, splinters, or insect bites, are favorite locations of entry for the bacteria. The bacteria can also be introduced through burns, any break in the skin, and injection-drug sites. Tetanus can also be a hazard to both the mother and newborn child (by means of the uterus after delivery and through the umbilical cord stump).

• The potent toxin that is produced when the tetanus bacteria multiply is the major cause of harm in this disease.

What is the incubation period for tetanus?

• The incubation period between exposure to the bacteria in a contaminated wound and development of the initial symptoms of tetanus ranges from two days to two months, but it's commonly within 14 days of injury.

Tetanus Causes

Clostridium tetani is a gram-positive rod-shaped bacterium that is found worldwide in soil; it is usually in its dormant form, spores, and becomes the rod-shaped bacterium when it multiplies. The vegetative rods produce the spore usually at one end of the rod The organisms are considered anaerobic.

Clostridium tetani is the bacterium responsible for the disease. The bacteria are found in two forms: as a spore (dormant) or as a vegetative cell (active) that can multiply.

The spores are in soil, dust, and animal waste and can survive there for many years. These spores are resistant to extremes of temperature.

Contamination of a wound with tetanus spores is rather common. Tetanus, however, can only occur when the spores germinate and become active bacterial cells.

The active bacterial cells release two exotoxins, tetanolysin and tetanospasmin. The function of tetanolysin is unclear, but tetanospasmin is responsible for the disease.

The disease typically follows an acute injury or trauma that results in a break in the skin. Most cases result from apuncture wound, laceration (cut), or an abrasion (scrape).

Other tetanus-prone injuries include the following:– frostbite,– surgery,– crush wound,– abscesses,– childbirth,– IV drug users (site of needle injection).

Wounds with devitalized (dead) tissue (for example, burns or crush injuries) or foreign bodies (debris in them) are most at risk of developing tetanus.

Tetanus may develop in people who are not immunized against it or in people who have failed to maintain adequate immunity with active booster doses of vaccine.

Picture of Clostridium tetani, with spore formation (oval forms at end of rods)

SymptomsTetanus often begins with mild spasms in the jaw muscles

(lockjaw). The spasms can also affect the chest, neck, back, andabdominal muscles. Back muscle spasms often cause arching, called opisthotonos.

Sometimes the spasms affect muscles that help with breathing, which can lead to breathing problems.

Prolonged muscular action causes sudden, powerful, and painful contractions of muscle groups. This is called tetany. These episodes can cause fractures and muscle tears.

Other symptoms include:DroolingExcessive sweatingFeverHand or foot spasmsIrritabilitySwallowing difficultyUncontrolled urination or defecation

Signs and tests

• Your doctor will perform a physical exam and ask questions about your medical history. No specific lab test is available to determine the diagnosis of tetanus.

• Other tests may be used to rule out meningitis, rabies, strychnine poisoning, and other diseases with similar symptoms.

Treatment

Treatment may include:

• Antibiotics, including penicillin, clindamycin, erythromycin, or metronidazole (metronidazole has been most successful)

• Bedrest with a nonstimulating environment (dim light, reduced noise, and stable temperature)

• Medicine to reverse the poison (tetanus immune globulin)

• Muscle relaxers such as diazepam

• Sedatives

• Surgery to clean the wound and remove the source of the poison (debridement)

• Breathing support with oxygen, a breathing tube, and a breathing machine may be necessary.

Expectations (prognosis)

• Without treatment, one out of four infected people die. The death rate for newborns with untreated tetanus is even higher. With proper treatment, less than 10% of infected patients die.

• Wounds on the head or face seem to be more dangerous than those on other parts of the body. If the person survives the acuteillness, recovery is generally complete. Uncorrected episodes of hypoxia (lack of oxygen) caused by muscle spasms in the throat may lead to irreversible brain damage.

Complications

Airway obstruction

Respiratory arrest

Heart failure

Pneumonia

Fractures

Brain damage due to lack of oxygen during spasms

How is tetanus prevented?

• Active immunization ("tetanus shots") plays an essential role in preventing tetanus. Preventative measures to protect the skin from being penetrated by the tetanus bacteria are also important. For instance, precautions should be taken to avoid stepping on nails by wearing shoes. If a penetrating wound should occur, it should be thoroughly cleansed with soap and water and medical attention should be sought. Finally, passive immunization can be administered in selected cases (with specialized immunoglobulin).