Page 139 - JSOM Winter 2018

An Ongoing Series

Tetanus

Mark W. Burnett, MD

Introduction minutes, and complete recovery from the disease may take
months. Death rates range from 10% to 20% for this form
An earthquake strikes a developing world nation without of the disease. Neonatal tetanus may occur when an infant is
warning in the middle of the night, turning the poorly built born to a mother who is not immunized against tetanus and
homes and apartment buildings into piles of cinderblocks and has not acquired transplacental antibodies against the disease
twisted corrugated metal. Survivors are pulled from the rubble prior to birth. This form of tetanus is most common in poor
by neighbors, as well as by members of a US military unit that areas where care of the umbilical stump is not hygienic follow-
is training in the area. Once the survivors have their airway, ing birth. Localized tetanus, where the muscle spasms occur in
breathing, and circulation assessed, another more insiduous a localized area near the contaminated wound, and cephalic
threat to life has to be addressed and not forgotten—the risk tetanus, in which cranial nerves palsies can result, are far less
of tetanus.
common—but both may progress to the generalized form of
the disease (Figures 1–3).
Background and Clinical Presentation
Tetanus is a caused by a neurotoxin produced by an anaero-
bic, spore-forming, gram-positive bacillus named Clostridium FIGURE 1 This 1965
photograph depicts the face
tetani. The bacterium itself is sensitive to hot environments as of a 46-year-old man that
well as oxygen, but the spores it produces are resistant to heat displayed the characteristic
and antiseptic agents. Soil of agricultural areas throughout the facial muscle spasm known
world contains the spores, which are harbored in the intestines as rictus, caused by the toxins
produced by the bacterium,
of numerous types of farm animals as well as rats, dogs, and Clostridium tetani. This
cats. Humans who work close to the land may have their skin facial appearance lead to this
colonized, making them potentially at risk for infection. condition becoming known as
lockjaw. In this particular case,
the tetanus was attributed to
The bacterium and the spores it produces can enter through shell fragments embedded in a
breaks in the skin caused by injuries as diverse as cuts by metal, wound to his hand.
abrasions, puncture wounds, compound fractures, crush inju-
ries, gunshot wounds, burns, and frostbite. In the low-oxygen,
anaerobic environment of a wound, the spores germinate and Source: CDC/ Armed Forces Institute of Pathology (AFIP)/ C. Farmer;
https://phil.cdc.gov/Details.aspx?pid=1657
produce toxins that are spread though the blood and lym-
phatic systems. Following an incubation period of between 3 Diagnosis
days and 3 weeks, the disease can manifest itself in the forms
of generalized tetanus (including neonatal tetanus), local tet- The diagnosis of tetanus is made clinically, based on the unique
anus, and cephalic tetanus. In all types of tetanus, the toxin appearance of the physical findings. Isolation of the organism
produced interferes with neurotransmitter release that in turn in a wound happens in less than one-third of all cases—and
leads to muscle spasms and continuous involuntary muscle can occur in patients who do not have the disease.
contraction or tetany.
Treatment
Generalized tetanus is the most common form of tetanus, rep-
resenting three-fourths of all cases worldwide. In adults, this Wound prophylaxis against tetanus requires a clinical as-
disease manifests as descending muscle contraction involving sessment to determine if the wound is “clean and minor” or
the jaw (“lockjaw”), often progressing to involve muscles of “dirty or contaminated.” For clean wounds, if vaccine history
the neck, throat, and abdomen. Spasms may last for several is unknown or is fewer than three doses or if the most recent
COL Burnett is currently chief of Pediatric Infectious Diseases at Tripler Army Medical Center in Hawaii and is the pediatric subspecialties
consultant to the US Army Surgeon General. He is board certified in pediatrics and pediatric infectious diseases. He has served overseas in
Korea, Germany, Kosovo, Iraq, Afghanistan, and Kuwait and as the JSOTF-P surgeon in the Philippines. He is a graduate of the University of
Wisconsin-Madison and the Medical College of Wisconsin.

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