Clostridium Tetani Diagnosis

Clostridium tetani is the rod-shaped bacterium that causes tetanus in humans. These bacteria are common in soil and animal feces. Though only about 50 cases of tetanus occur in the U.S. per year, it remains a significant cause of death in other parts of the world. Laboratory tests are generally ineffective in identifying infection by Clostridium tetani. Therefore, doctors often diagnose tetanus by identifying symptoms and the circumstances leading to infection.

Infection

• The most common cause of infection by Clostridium tetani worldwide is poor hygiene that leads to infection of the umbilical stump in infants. In the U.S., infection is usually caused by contamination from soil, manure or rusted metal. Frequent use of intravenous drugs increases the risk of tetanus. Individuals with open sores, including burns, bites, ulcers, gangrene or surgical scars, also have a higher risk of tetanus infection.

Symptoms

• The symptoms of tetanus are an important aspect of diagnosis. Jaw and neck stiffness, commonly leading to a condition known as "lockjaw," is a telltale sign. Difficulty swallowing, pain at the site of infection and spasms of the neck, back, abdominal and respiratory muscles are not uncommon. Respiratory spasms can lead to obstruction of the airway and asphyxiation.

Onset

• A lag time of anywhere from five days to two weeks typically passes between the incident that causes the infection and the appearance of symptoms. This delay leads most physicians to administer antimicrobial and immune globulin treatment preemptively whenever a high-risk event occurs. This makes medical history, particular the occurrence of some particular opportunity for infection, the most important aspect of tetanus diagnosis.

Progression

• Once infection by Clostridium tetani has set in, the first symptoms appear in the head and neck and gradually spread through the rest of the body. Spasms that arch the back appear in waves, along with general muscle rigidity and dysfunction of the autonomic nervous system. In localized tetanus, where a relatively minor infection has produced a small toxin load, spasms may be limited to a part of the body near the site of infection. If left untreated, cephalic tetanus develops and results in nerve dysfunction and damage, heart arrhythmia and fever.

Medications

• The preferred medication for treatment of tetanus, according to Johns Hopkins, is 7.5mg/kg metronidazole given intravenously over six hours. Alternatively, penicillin, erythromycin, tetracycline, chloramphenicol or clindamycin can be used. In cases where the toxin produced by the infection has not yet interacted with body tissues, tetanus immune globulin (TIG) can be used to neutralize the infection. Vaccination against tetanus is the most common form of prevention.