Clostridium Tetani Flashcards
What is the shape of clostridium tetani?
Bacillus/ rod shaped
What cells does it affect and how?
Tetanospasmin enters Renshaw cells and cleaves SNARE proteins which are responsible for pulling vesicles containing neurotransmitters to the neuron membrane. This prevents the release of these inhibitory neurotransmitters called Glycine and Gaba.
What cells does it affect and how?
Toxin binds to the presynaptic membrane; it is internalized through endocytosis. Light chain is translocated across the membrane. The L chain acts as specific endopeptidase against synaptobrevin (a synaptic vesicle protein necessary for vesicle fusion with the plasma membrane) Without intact synaptobrevin, synaptic vesicles accumulate at
the nerve ending, unable to release their contents of the inhibitory neurotransmitters
How does it enter the body?
Spores are likely to enter by penetrating trauma like a puncture wound. It can be from dirty wounds like a rusty nail or even a clean wound like a kitchen knife. The puncture wound is warm and anaerobic and ideal for growth of clostridial spores
How long does it take to notice tetanus?
Tetanus has a delayed onset of about a week to a month after initial injury.
What is the triad of symptoms of tetanus?
Trismus: Mild to severe muscle spasms of lower jaw
Risus Sardinius: Abnormal sustained grin caused by facial muscle spasm
Opisthonos: Severe spasm of all muscles silmutaneously
Define local tetanus
This is when persistent spasms are localized only around the area of injury. Can persist for a few months but then subsides.
Define cephalic tetanus and how it happens
This is limited to muscles supplied by Cranial nerves only. Happens in cases of head trauma such as skull fractures, eye injuries, middle ear infections and tooth extractions. More likely to cause death.
Define neonatal tetanus and how it happens
Affects newborns of mothers who have not been immunized when the umbilical cord is cut by a non sterile instrument. Newborns of immunized mothers are protected by passive immunity
What is the diagnosis of tetanus?
Spatula test is done: Wooden spatula is used to touch the posterior pharyngeal wall. Positive test results in involuntary contraction of the jaw.
Bioassay can be used to detect toxin in the serum
Why is it difficult to culture Clostridium Tetani?
Anaerobes are very slow to grow
What is the treatment for tetanus?
Treated with tetanus immune globulin, a antitoxin that binds to tetanospasmin.
Muscle relaxants
Pain medication and other supportive care measures are taken while immune system clears infection.
How long does it take to fully recover from tetanus?
Full recovery takes months of intensive care
A 22-year-old male presents to the emergency department with a gunshot wound to the abdomen. The bullet did not puncture the patient’s bowel but did lacerate the
spleen The patient was given a splenectomy and then transferred to the intensive care unit. However, the next day, the patient developed a rigid abdomen and then began clenching his fists and arching his back.
What would be the next best step in the management of this patient?
This patient has a tetanus infection that entered through the gunshot wound, likely while the patient was on the ground following the injury. Patients with early tetanus can, in rare circumstances, develop abdominal rigidity similar to the presentation of an acute surgical abdomen. However, the presence of other classic tetanus symptoms differentiate tetanus
from surgical abdomen. These symptoms include: stiff neck, risus sardonicus, periods of apnea, dysphagia
, clenched fists, arched back, and flexed, abducted arms with extended legs.
All patients with tetanus should undergo wound debridement and be give tetanus immune globulin. Because tetanus spores germinate in necrotic tissue
, debridement helps to eliminate both the spores and their germination environment. In addition to wound debridement and immune globulin, patients may also be given muscle relaxants to help control spasms, though this does not help treat the infection itself. If a person’s breathing seems to be affected, mechanical ventilation may also be given as supportive treatment.
How many kinds of Vaccines are there against tetanus?
Diphteria and tetatnus (DT) Diphtheria, tetanus and pertussis (DTaP) Tetanus and diphteria (Td) Tetanus, diphteria and pertussis (Tdap) 4 total
