Transcript tetanus toxoid
TETANUS
Manvi gupta
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Introduction.
Definition
Tetanus is an acute , often fatal disease caused by an
exotoxin
produced by the bacterium C
lostridium tetani.
But prevented by immunization with tetanus toxoid
.
It is characterized by generalized rigidity and convulsive spasms of skeletal muscles . The muscle stiffness usually involves the jaw (lockjaw)and neck and then becomes generalized.
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Introduction (con ).
History:
•
Tetanus was first described in Egypt over 3000 years ago(Edwin smith papyrus).
• It was again described by Hippocrates •Carle and Rattone in 1884 who first noticed tetanus in animals by injecting them with pus from a fatal human tetanus case.
•During the same year , Nicolaier produced tetanus in animals by injecting them with samples of soil.
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Introduction(con).
History:
•In 1889, Kitasato isolated the organism from a human victim,showed that it produced disease when injected into animals,and reported that the toxin could be neutralized by specific antibodies.
•Nocard demonstrated the protective effect of passively transferred antitoxin,and passive immunization in humans •Passive immunization and prophylaxis for tetanus during World War I •Tetanus Toxoid was first widely used during world war II [email protected]
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Causative Organism Clostridium tetani
Acridine orange stain of characteristic C tetani with endospores wider than the characteristic drumstick shape. [email protected]
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Clostridium tetani
• C.tetani
is : * a slender gram-positive, anaerobic rod that may develop a terminal spore giving it a drumstick appearance.
* It is sensitive to heat presence of oxygen.
and cannot survive in the
• It produces two exotoxins :
1) tetanolysin .
its function of is not known with certainty. 2) tetanospasmin is a neurotoxin and causes the clinical manifestations of tetanus.
Tetanospasmin estimated Human lethal dose is 2.5 ng/kg ( (a nanogram is one billionth of a gram) [email protected]
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Courtesy : Google Image on tetanus [email protected]
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Spores:
*very resistant to heat and the usual antiseptics.
•They can not survive autoclaving at minutes.
(121 °C)for 20 • relatively resistant to phenol agents.
& other chemical • widely distributed in soil and faces of horses, sheep, cattle , dogs , cats , rats, guinea pigs , and chickens.
and in the intestines Manure-treated soil may contain large numbers of spores . Spores may persist for months to years. [email protected]
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Epidemiology: a:Occurrence. b:Reservoir .
c:Mode of Transmission d:Communicability
Source : CDC.,google pictures 10
Epidemiology:
• Tetanus - Greek Word -- Tetanos -to Contract • Tetanus Remains a Major Public Health Problem in the Developing World and Is Still Encountered in the Developed World.
• There Are about 800 000 : 1 Million Deaths Due to Tetanus Each Year.
80%
of These • Deaths Occur in and It Remains Endemic in 90 Countries World Wide.
Africa and South East Asia
1998 - U.K,USA 7 Cases, 41 Cases Including One Neonate
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Epidemiology(con):
•
Occurrence:
Tetanus occurs worldwide but is most frequently encountered in densely populated regions in
hot , damp climates with soil rich in organic matter.
•
Reservoir :
Organisms are found primarily in the soil and intestinal tracts of animals and humans.
•
Mode of Transmission:
is primarily by: * contaminated wounds, *Tissue injury( surgery , burns , deep puncture wounds , crush wounds , Otitis media ,dental infection , animal bites, abortion , and pregnancy).
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Epidemiology (contu ):
•Communicability
Tetanus is not contagious from person to person .It is the only vaccine preventable disease that is : “ infectious but not contagious” .
Temporal pattern : Peak in winter and summer season.
Incubation Period : 8 DAYS ( 3-21 DAYS)
Source : CDC.,google pictures 13
Host Factors :
• Age : I t is the disease of active age (5-40 years), New born baby, female during delivery or abortion • Sex : males
>
females • Occupation risk : Agricultural workers are at higher • Rural
>
Urban areas .
• Immunity : Herd immunity( community immunity) does not protect the individual.
• Environmental and social factors : Unhygienic custom habits , Unhygienic delivery practices.
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Pathogenesis .
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Pathogenesis
*C. tetani usually enters the body through a wound.
*In the presence of anaerobic conditions, the spores germinate and start to produce toxin and disseminated via blood and lymphatics.
*Toxin reaches the CNS . by passing along the motor nerves to the anterior horn cells of the spinal cord . (The shortest peripheral nerves are the first to deliver the toxin to the CNS, which leads to the early symptoms of facial distortion and back and neck stiffness.) *Toxins act at several sites within the central nervous system, including : 1) peripheral motor end plates, 2) spinal cord, 3) brain, 4) sympathetic nervous system. [email protected]
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How tetanospasmin reaches the CNS .
• Tetanospasmin is taken up by motor neurons in the peripheral nerve endings through
endocytosis
. It then travels along the axons until it reaches the motor neuron cell bodies in the spinal cord, by fast retrograde transport.
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Speed of toxin transport:
The toxin travels via intra axonal transport at a rate of 75 -250 mm/day .
A process which takes 2 -14 days to reach the CNS.
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Pathogenesis (con )
The typical clinical manifestations of tetanus are caused when tetanus toxin interferes with release of neurotrans mitters blocking inhibitory impulses. This leads to unopposed muscle contra ction and spasm. Seizures may occur, and the autonomic nervous system may also be affected.
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Mechanism of Action of Tetanus Toxin
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Clinical Features
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Incubation period :
I P. ranges from
3 to 21 days
, usually about 8 days. In general : *The further the injury site is from the CNS, the longer the I P. *The shorter the I P, the higher the chance of death. * In neonatal tetanus, symptoms usually appear from
4 to 14 days
after birth, averaging about 7 days. [email protected]
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Types of tetanus
: (On the basis of clinical findings, three different forms of tetanus have been described) . 1)
Local tetanus
is an uncommon form of the disease,in which patients have persistent contraction of muscles in the same anatomic area of the injury.
Local tetanus may precede the onset of generalized tetanus but is generally milder .Only about 1%of cases are fatal.
23 Source : CDC.
Types of tetanus(con)
2)Cephalic tetanus
is a rare form of the disease, occasionally occurring with otitis media(ear infections)in which
C. tetani
is present in the flora of the middle ear , or following injuries to the head . There is involvement of the cranial nerves, especially in the facial area. [email protected]
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Types of tetanus(contu)
3)
generalized tetanus
It is The most common type (about 80%)of reported tetanus .The disease usually presents with a descending pattern.
Neonatal tetanus is a form of generalized tetanus
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Sequence of events
Lock Jaw Stiff Neck Difficulty Swallowing Muscle Rigidity Spasms
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Risus Sardonicus in Tetanus Patient
A person suffering from tetanus undergoes convulsive muscle
contractions of the jaw--called LOCKJAW
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Opisthotonos in Tetanus Patient
The contractions by the muscles of the back and extremities may become so violent
and strong that bone fractures may occur
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Opisthotonos in Tetanus Patient
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Oposotinus postion in tetanus [email protected]
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Unfortunately, the affected individual is
conscious throughout the illness,
but cannot stop these contractions
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Rusty nail may cause prick &
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Type of Tetanus
Traumatic T.
Puerperal T.
Otogenic T.
Idiopathic T.
T. Neonatorum
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Complications .
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Diagnosis
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Laboratory diagnosis
*There are
no laboratory findings
characteristic of tetanus. *The diagnosis is
entirely clinical
and does not depend upon bacteriologic confirmation.
•C. tetani is recovered from the wound in only 30% of cases and can be isolated from patients who do not have tetanus. •Laboratory identification of the organism depends most importantly on the demonstration of toxin production in mice. [email protected]
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Clinically it is confirmed by noticing the following features: 1. Risus sardonicus or fixed sneer .
2. Lock jaw .
3. Opisthotonos position.) ( extension of lower extremities, flexion of upper extremities and arching of the back. The examiners hand can be passed under the back of the patient when he lies on the bed in supine 4. Neck rigidity [email protected]
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Diagnostic tests for tetanus:
Spatula Test
: Apet and Kamad discribe a simple bedside test to diagnose tetanus : the posterior pharyngeal wall is touched with a spatula and a reflex spasm of the masseters indicates a +ve.test.
This test shows 94 % sensitivity . and 100 % specificity.
The altered whistle
: This explained as an early effect of tone in facial muscles which causes the classic R . sardonicus [email protected]
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scale for the severity and the prognosis of tetanus: Score
:
One point
for each of the following
7 items
: •
I P
.
<
7 days (period between injury and 1 st .symptom.) •
Period of onset
<
48 hours ( period between 1 st . Symptom and 1 st . Spasm. ) •
Acquired from
burns, surgical wounds, compound fractures, or septic abortion .
•
Addiction
(Narcotics) •
Generalized
tetanus •
Temperature
•
Tachycardia
greater than 104 ° F (40 ° C) greater than 120 beats per minute (>150 42
Total score indicates the severity and the prognosis as follows:
Score
Severity Prognosis (mortality rate) 0 -1 2 -3 4 5 : 6 mild moderate severe very severe
< 10 % 10 : 20 % 20 : 40 % > 50 %
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1) Medical Management .
2)
Wound Management .
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Medical Management
Aim of TTT:
(1) provide supportive care ( until the tetano spasmin that is fixed in tissue has been metabolized ) by : • a: treatment of muscle spasm, • b: prevention of respiratory complications. • c: prevention of metabolic complications.
(2)
neutralization
of circulating toxin to prevent the continued spread. (3)
elimination of the source of toxin
.
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How to treat :
1: Admit patients with
severe:
to the (
ICU
). For risk of reflex spasms . 2: maintain a
dark and quiet room
for the patient. 3: Avoid unnecessary procedures .
4: Seriously consider
prophylactic intubation
with succinylcholine in all patients with moderate to-severe clinical manifestations. Intubation and ventilation are required in 67% of patients . [email protected]
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How to treat :
5:Perform
tracheostomy
in patients requiring intubation for more than 10 days. Tracheostomy has also been recommended after onset of the first generalized seizure.
7:
Tetanus immune globulin
(TIG)(passive immunization) is recommended for treatment of tetanus. TIG can only help remove unbound tetanus toxin, but it cannot affect toxin bound to nerve endings. A
single IM. dose of 3000-5000 units is generally recommended
be identified.
for children and adults, with part of the dose infiltrated around the wound if it can [email protected]
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How to treat : Recovered individuals :
do not necessarily develop “natural Immunity”
against the infection---
because of
extreme potency
of the toxin and
very small amount
produced during the infection, It does not elicit a strong , protective immune response which would produce enough antibodies against future re-infection.
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How to treat : SO
Active immunization with tetanus toxoid
should begin or continue as soon as the person’s condition has stabilized.
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Drugs:
1) Penicillin G:
Adult
10-24 million U/d. ( IV/IM/6h. )
Pediatric
100,000-250,000 U/kg/d. (IV/IM/6h. ) ( 10- to 14-d course of treatment is recommended.) [email protected]
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Drugs:
2) Metronidazole : *considered as a drug of choice by many.
* has a better safety profile, better tissue penetrability and negligible CNS excitability.
(penicillin can cause seizures at high doses).
It can also be given rectally
Adult
500 mg orally/6h or 1 g IV /12h; not to exceed 4 g/d
Pediatric
15-30 mg/kg/d IV divided /8-12h; not to exceed 2 g/d 51
Drugs:
3)Doxycycline : Used when there is contraindication to penicillin or metronidazol.
Adult
100 mg orally/IV /12h
Pediatric
<8 years: Not recommended <45 kg : 4.4 mg/kg/d) PO/IV divided bid > 45 kg: Administer as in adults [email protected]
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Drugs:
Anticonvulsants:
Sedative-hypnotic agents are the mainstays of tetanus treatment.
1) Diazepam (Valium): Depresses all levels of CNS, including limbic and reticular formation, possibly by increasing activity of GABA(γ-Amino-butyric acid ), a major inhibitory neurotransmitter.
Adult
Mild spasms: 5-10 mg PO /4-6h Moderate spasms: 5-10 mg IV(diluted in 8 ml glucose 5% or saline ) Severe spasms: Mix 50-100 mg in 500 mL D5W and infuse at 40 mg/h
Pediatric
Mild spasms: 0.1-0.8 mg/kg/d PO divided tid/qid Moderate or severe spasms: 0.1-0.3 mg/kg IV q4-8h [email protected]
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2) Phenobarbital: used to * prolong effects of diazepam.
* treat severe muscle spasms.
Adult
1 mg/kg IM q4-6h; not to exceed 400 mg/d
Pediatric
5 mg/kg/d IV/IM divided tid/qid [email protected]
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Skeletal muscle relaxants
These agents can inhibit both monosynaptic and polysynaptic reflexes at spinal level, possibly by hyperpolarization of afferent terminals.
* Baclofen (Lioresal) a physiological GABA agonist
Adult
<55 years: 1000 mcg IT(intrathecal) >55 years: 800 mcg IT
Pediatric
<16 years: 500 mcg IT >16 years: Administer as in adults [email protected]
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Differential Diagnoses
Mandible dislocations, Stroke , Encephalitis Subarachnoid Hemorrhage Hypocalcemia Dystonic Reactions Meningitis Peri-tonsillar Abscess Rabies
Other Problems to Be Considered
Intraoral disease Odontogenic infections Globus hystericus Hepatic encephalopathy Hysteria Strychnine poisoning [email protected]
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Wound Management .
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All wounds should be cleaned with
H2O2
&antiseptic.
Necrotic tissue and foreign material should be removed.
Passive immunization.
Active immunization. Or Both.
PREVENTION
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PREVENTION How to kill spores :
• Spores are extremely stable ,but killed by: Immersion in boiling water for 15 • • minutes.
Autoclaving for 15-20 minutes at 121 ° c.
Sterilization by dry heat for 1 -3 hrs at • 160 °C.
Ethylene oxide sterilization is sporocid .
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PREVENTION
Fumigation
• Sterilization of
operation theatre
by : * 500 ml of formalin , 200gms of Pot permanganate/30 cu . meters of space *All windows and doors are closed except one . *Fissures between the panels of the doors and windows are closed with adhesive tape *After 12 hours the doors and windows are opened and the theatre is aired for 24 hours before decommissioning it.
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Active Immunization
by using tetanus toxoid
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TETANUS TOXOID
• Tetanus toxoid was developed by Descombey in 1924, • Tetanus toxoid immunizations were used extensively in the armed services during World War II.
• Tetanus toxoid consists of a formaldehyde-treated toxin.
• There are two types of toxoid available — 1) adsorbed (aluminum salt precipitated)toxoid 2) fluid toxoid equal,the .
• Although the rates of seroconversion are about adsorbed toxoid is preferred because the antitoxin response reaches higher titers lasting and is than that following the fluid toxoid.
longer [email protected]
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Passive Immunization
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Passive Immunization
1. ATS(equine)I g. 1500 IU/s.c after sensitivity test (or) 2. ATS(human)I g. 250-500 IU, no anaphylactic shock, very safe and costly.
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Tetanus Neonatorum.
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Newborn showing risus sardonicus and generalized spasticity
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THANK YOU
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