A 23 year old male patient demonstrating severe face and arm muscle spasms was brought to the emergency department by his brother. You note that the patient has many tattoos, including a fresh one on his shoulder. The brother tells you that the patient just got that tattoo yesterday, and that the tattoo parlor was “sketchy.” You order blood tests, and when you get the results, it confirms your suspicion: this patient is infected with Clostridium tetani, a common bacterium found in soil that can be transmitted by using dirty needles. The patient was never vaccinated against this bacterium. Clostridium tetani produces a toxin that affects neurons and their ability to release neurotransmitters. The worried brother asks you to explain this patient’s condition.

Upstream Causes

Direct causes

Severe face and arm muscle spasms

Can't speak

Fresh tattoo from possibly a dirty needle

HIV

Tetanus

Hepatitis B or C

Hep C

Fever

yellowish skin tone (Jaundice)

Swollen lymph nodes

Fever lasting more than 10 days

Being tired all the time

Hep B

Jaundice

Fever

Fatigue

Apetite loss

dangerous nerve ailment caused by the toxin of a common bacterium, Clostridium tetani.

Sudden, involuntary muscle tightening (muscle spasms) – often in the stomach

Painful muscle stiffness all over the body

Trouble swallowing

Jerking or staring (seizures)

Headache

Fever and sweating

Changes in blood pressure and fast heart rat

Indirect cause

Was never vaccinated for tetanus

DTaP vaccine protects young children from diphtheria, tetanus, and whooping cough

DT vaccine protects young children from diphtheria and tetanus

Tdap vaccine protects preteens, teens, and adults from tetanus, diphtheria, and whooping cough

Most all patients that present with tetanus is because they were not vaccinated

It is not a transferable disease

You can not get it from contact with someone

Jaw Cramping

Bacteria is most commonly found in soil

1657_lores

6373_lores

But can also be found in animal excrement, house dust, and the human colon

These spores enter the skin in this case via the infected tattoo needle

Produce a neurotoxin, tetanospasmin that enters your bloodstream

Your bloodstream carries the toxin to your nerves

Toxin/poison begins to block the relaxation muscle signals

Causing sustained muscle contractions shown above in both pictures

Eventually it will make it difficult to breath

Anatomy

Down stream causes

Physiology

Nervous tissue

Excitation Contraction

Organ systems

Nervous system: Detects & responds to stimuli

Muscular system: Assists with movement & heat production

Peripheral nervous system (PNS)

Central Nervous system (CNS)

Brain

Nerves and ganglia outside the brain and spinal cord

Autonomic nervous system

Somatic nervous system

Involuntary

Voluntary

Sympathetic nervous sysmtem

Parasympathetic nervous systems

Neurons

Axons

3 types of neurons

Axon hillock

Axon terminals

Myelin sheath

Nissl Body

Cell body

Node of ranvier

Dendrites

Schwann cell

Bi bolar

Multi polar

Uni polar

Cone shaped area where the axon leaves the cell body

Ends of the axon that contain synaptic vesicles

portion of the neuron that carries the impulse away for the cell body

Region of the neuron that receives incoming signals and conveys then towards the cell body

Fatty layers that surround and electrically-insulate the axon

Granules of touch endoplasmic reticulum in the cytoplasm

Gaps between the Schwann cells on a neurons axon

Cells that form myelin sheaths around axons of neurons in the central nervous system

Portion of the neuron that carries the impulse away form the cell body

Neurons with one extension off of their cell body

Neurons with two extensions from the cell body

Neurons with multiple extensions from the cell body

Most abundant

Found in special sensory organs: retina of the eye

commonly found in the dorsal root ganglia of the spinal cord

Synapse is a location where two neurons meet and exchange messages

Presynaptic neuron

Synaptic cleft

Neurotransmitter

Postsynaptic neuron

Chemical messengers released from the presynaptic neuron bind to the postsynaptic neuron

Neuron located before the synapse

Area of indirect contact between the presynaptic and postsynaptic neurons

Neuron location after synapse

Clostridium tetani

Excitatory VS Inhibitory

Summation

Process of converting an electrical stimulus to a mechanical response

Skeletal muscle fibers

Skeletal muscle cells

sarcolemma

T-tubules

sarcoplasmic reticulum

Plasma membrane of muscle fibers

extensions of the cell membrane that penetrate into the centre of skeletal and cardiac muscle cells

Stores calcium

Occurs when a neuron uses more than one message to determine if it should depolarize

Excitatory Neurotransmitters

Inhibitory Neurotransmitters

Hyper polarize the membrane

Make it more negative

Depolarize the membrane

Make it more positive

Excitatory postsynaptic potentials (EPSP)

Inhibitory postsynaptic potentials (IPSP)

Temporal summation

Spatial Summation

No summation

A message being transmitted every so often

A message being told by one person over and over

A message being told by multiple people at the same time

common soil bacterium

Rod shaped

Gram postive bacterium

Withstand extreme temperature conditions

C0214503-Clostridium_tetani

neuron-structure

synapse-28463798

types-of-neurons-QBI

Clostridium Tetani

Excitatory VS Inhibitory

Neurons

Process of summation

Organ system

Excitation-Contraction Coupling

Nervous system

Muscular system function

PNS

CNS

connect the CNS to the limbs and organs

The somatic nervous system

The autonomic nervous system

responsible for carrying sensory and motor information to and from the central nervous system

Voluntary movement

Sensory Neurons

Motor neurons

Sensory Neurons

Motor neurons

Carry info from nerves to CNS

Carry info from the brain and spinal cord to muscle fibers through out the body

Sensory info

Physical action in response to stimuli

responsible for regulating involuntary body functions

Like breathing and your heart beat

system allows these functions to take place without needing to consciously think about them happening

The parasympathetic system

The sympathetic system

maintain normal body functions and conserve physical resources

Once the treat has passed this system helps body go back to "normal"

slow the heart rate, slow breathing, reduce blood flow to muscles, and constrict the pupils

regulates the flight-or-fight response

prepares the body to expend energy and deal with potential threats

triggers a response by speeding up heart rate, increasing breathing, increasing blood flow to muscles, activating sweat secretion, and dilating the pupils

Allows the body to respond quickly to the situation

responsible for integrating sensory information and responding accordingly

Brain

Spinal cord

central control module of the body and coordinates activity

physical motion, secretion of hormones, the creation of memories, and the sensation of emotion

Spinal cord

carries information between the brain and body, but also carries out other tasks

connects with the nerves of the peripheral nervous system

Motor commands from the brain travel from the spine to the muscles

Sensory information travels from the sensory tissues toward the spinal cord and finally up to the brain

Contains circuits that control certain reflexive responses, such as involuntary movement your arm might make if you burn your finger

Spinal nerves can coordinate all of the muscles necessary to walk

Movement of our bodies which is voluntarily controlled by skeletal muscles

Involuntary movement happens with your smooth muscles and cardiac muscles

Food digestion (smooth muscles)

Walking, running, or swimming to name a few

Heart beat and blood flow (cardiac muscles)

electrically excitable cells in the nervous system that function to process and transmit information

Neurons send signals using action potentials

a shift in the neuron’s electric potential caused by the flow of ions in and out of the neural membrane

interneurons

motor neurons

Sensory neuron

Smell, hear, taste,feel and see

Most common type

Pass signals from sensory neurons and other interneurons to motor neurons

Movement

Involuntary

Voluntary

allow the brain and spinal cord to communicate with muscles, organs, and glands all over the body

The sequence of events converting action potentials in a muscle fiber to contraction

Motor neurons synapse with muscle cells at the neuromuscular junction

They release acetylcholine (ACh)

ACh attaches to chemically gated sodium ion channels on sarcolemma

Causing Sodium to rush in and depolarizes

Voltage-gated calcium channels open

calcium binds to troponin

Tropomyosin unblocks the myosin-binding sites on actin

myosin attaches to and slides past actin

Two types of summation

Excitatory increase the likelihood that the neuron will fire an action potential

Inhibitory decrease the likelihood that the neuron will fire an action potential

Depolarize

Hyperpolarize

Neurotransmitter binding opens chemically gated ion channels allowing sodium and potassium to pass simultaneously

The electrochemical gradient for sodium is bigger than potassium so more sodium enters then potassium leaves and results in depolarization

Neurotransmitter binding opens chemically gated ion channels allowing either potassium of Chloride to pass

Resulting hyperpolorization

Spatial summation

Temporal summation

Receiving one message over and over again

Receiving the same message from multiple neurons over and over again

Neurons constantly bring (presynaptic) messages and receive (postsynaptic)messages

They add the messages together

The electrical sum of the messages predicts whether or not the neuron depolarizes

The number must reach -55mV (threshold) in order to have action potential

Will not have an action potential if -55mV is not met

Once it reaches threshold the action potential depolarizes up to +30

Voltage potassium gates opens to repolarize

Hyper polarization occurs, becomes to negative

With the help of leaky channels resting membrane potential is reached at -70 mV

Enters the body through a cut or break in the skin

Produces and releases a neurotropic exotoxin called tetanospasmin.

Transported with blood and lymph, and taken up via endocytosis by nerve cells at the neuromuscular junctions

Once inside the neurons, tetanus toxin cannot be neutralised by antitoxin

Tetanus toxin acts on four areas of the nervous system

Brain

Spinal cord

Sympathetic system

Motor end plates in the skeletal system

Toxin blocks the release of the inhibitory neurotransmitters glycine and gamma-amino-butyric acid in the central nervous system

Leaves excitatory nerve impulses unopposed resulting in muscle spasms

Nervous System

Painful muscle contractions

Particularly your jaw and neck

Also referred to as "lock Jaw"

Interferes with breathing and swallowing

No cure

Treatment focuses on managing complications until the effects of the tetanus toxin resolve

Complete recovery from a tetanus infection requires new nerve endings to grow, which can take up to several months.

Once tetanus toxin has bonded to your nerve endings it is impossible to remove

Skeletal system

Severity of spasms may cause the spine and other bones to break

Respiratory system

Pulmonary embolism

Blood clot that travels from one part of body blocks main artery of lung or one of its branches

Respiratory failure

Most common cause of death

Muscle spasms interfere or stop your breathing

Cardiovascular system

Lack of oxygen may induce cardiac arrest

Pneumonia

Blocks motor neurons