CNS conditions Flashcards
meninges
=An infection of meninges, protective tissue of the brain that causes stiff neck, headache and fever
caused by: Bacterial meningitis is caused by bacterial infection. This is contagious and deadly. Most common types of bacterial species that cause bacterial meningitis are, Streptococcus pneumonia – causes pneumococcal meningitis, Neisseria mengitidis – causes meningococcal meningitis. Listeria monocytogens and Haemophilus Influenza. This can spread through coughing, sneezing and sharing utensils, etc.
pop: mainly affects babies, preschool children and young people
risk factors: Age - Children below 5 years are more prone to develop viral meningitis. Bacterial meningitis is common in below 20 years of age, pregnancy, weakened immune system and skipping vaccinations
s&s: sudden onset of fever, headache, and stiff neck.
There are often other symptoms, such as headache with nausea or vomiting, decreased appetite, confusion or difficulty concentrating, sudden fever, severe headache that seems different than normal, seizures, sensitivity to light, Sleepiness, lethargy and a skin rash
prognosis: Untreated bacterial meningitis is almost always fatal. With treatment the risk of death is reduced. In new-borns the risk of death with treatment is 20 to 30%, in older children it is around 2% with treatment. The death risk is higher for adults even with treatment at 19 to 37%.
epilepsy
=a common neurological disorder that affects the brain caused by frequent seizures. Seizures are bursts of electrical activity in the brain that temporarily affect how it works.
focal seizure–> abnormal activity in just one area of your brain
generalised seizures–> all areas of the brain
causes: Genetics, Previous head trauma (car accidents), Brain abnormalities (brain tumours, stroke), Infections (meningitis, HIV), Prenatal injury (poor nutrients from mother), Developmental disorders (autism)
patho: Seizures are paroxysmal manifestations of the electrical properties of the cerebral cortex. A seizure occurs when there is a sudden imbalance between the excitatory and inhibitory forces within the network of cortical neurons in favour of a sudden onset net excitation.
risk factors: Age (common in children and older adults), Family history, Head injuries, Stroke and other vascular diseases (leads to brain damage), Dementia, Brain infections (meningitis, causes inflammation in the brain and spinal cord), Seizures in childhood
s&s: depends on which part of brain is affected. Uncontrollable jerking and shaking (known as a ‘fit’), Losing awareness and staring blankly into space, Becoming stiff, Strange sensations, such as a ‘rising’ feeling in the tummy and unusual tastes or smells, and a tinging feeling in your arms or legs, Collapsing, Psychological symptoms such as fear, anxiety or deja vu
treatment: Anti-epileptic drugs (main treatment), Surgery (remove part of the brain causing the seizures), Therapies (vagus nerve stimulation, ketogenic diet (low carbs + high protein), Deep brain stimulation (implanted electrodes into specific part of the brain to reduce seizures), Responsive neurostimulation (pacemaker-like device to help reduce number of seizures
parkinson’s disease
=a progressive neurodegenerative disorder associated with the loss of dopaminergic neurons mainly within the substantia nigra region of the brain. This causes a generalised slowing of movements (bradykinesia), resting tremors and rigidity in most patients.
caused by: largely unknown, Believed to be a combination of genetic and environmental factors, such as a use of pesticides and herbicides, Familial history usually affects younger patients (mutations in α-synuclein, parkin, UCHL1, DJ1, PINK1, and LRRK2 genes)
patho: Nerve cells in this part of the brain are responsible for producing a chemical called dopamine.
Dopamine acts as a messenger between the parts of the brain and nervous system that help control and co-ordinate body movements.
If these nerve cells die or become damaged, the amount of dopamine in the brain is reduced.
This means the part of the brain controlling movement cannot work as well as normal, causing movements to become slow and abnormal
s&s: develop gradually
tremour (often starting in hand or arm and occurs when limb is at rest), slowness of movement (bradykinesia), muscle stiffness (rigidity) can result in painful muscle cramps (dystonia), balance problems, loss of sense of smell, nerve pain, urinary problems, excessive sweating, difficulty swallowing, depression and anxiety, mild cognitive impairment, dementia
treatment: can’t be cured but medication can help control symptoms
Carbidopa-levodopa, Inhaled carbidopa-levodopa, Carbidopa-levodopa infusion, Dopamine agonists, MAO B inhibitors, Catechol O-methyltransferase (COMT) inhibitors, Anticholinergics, Amantadine, Adenosine receptor antagonists (A2A receptor antagonist), Nuplazid (Pimavanserin). surgery- deep brain stimulation
ddx: Essential tremor, Huntington chorea, Dementia with Lewy bodies, Progressive supranuclear palsy, Neuroacanthocytosis, Normal pressure hydrocephalus
MS
=chronic inflammatory, auto-immune disorder of CNS where there are multiple areas of de-myelination within the brain and spinal cord. The damage disrupts parts of the NS to transmit signals resulting in range of signs and symptoms, including physical, mental, and sometimes psychiatric problems.
caused by: unclear cause. Possibly genetics, and environmental factors.
patho: either destruction by the immune system or failure of the myelin-producing cells. Damage is believed to be caused, in-part, by attack on the nervous system by the person’s own immune system.
pop: prevalence increases with latitude (e.g. higher in N Europe, lower in tropics). females
risk factors: geographical location, genetic pre-disposition, viral infection
s&s: Central: fatigue, cognitive impairment, depression, anxiety, unstable mood. Visual: nystagmus, optic neuritis, diplopia. Speech: dysarthria. Throat: dysphagia. MSK: weakness, spasms, ataxia. Sensation: pain, hypoesthesias, paraesthesia. Bowel: incontinence, diarrhoea or constipation. Urinary: incontinence, frequency or retention
prognosis: typically, condition is slowly progressive. Average life expectancy is 30 years from the start of the disease (5-10 years less than that of unaffected people). 40% of MS patients reach the seventh decade of life. Most people lose the ability to walk before death, 90% are capable of independent walking at 10 years from onset, and 75% at 15 years.
ddx: spinal cord or brain neoplasm, encephalomyelitits, vit B12 deficiency (neuro degeneration), Schilder disease (children), diabetes, hypertension, hyperlipidemia, arthritis (RA, ReA, PA)
Temporal arteritis
=a type of vascular inflammatory condition that affects the arteries near the temples of the head that supply the scalp. This usually occurs when the vessels become inflamed or constricted.
caused by: unknown, possibly an autoimmune response
pop: over 50s, more women than men.
s&s: a throbbing, continuous headache. Other symptoms include loss of appetite/weight loss, fatigue, fever, tenderness on the scalp or temples, jaw pain that becomes worse after chewing, muscle aches in the arms, shoulders, hips, thighs, lower back and buttocks, and vision problems e.g., double vision, blurry or transient vision loss which can lead to permanent vision loss if not treated.
treatment: There is currently no cure for this condition. But in order to prevent any further damage treatment should be sought immediately. Treatments that are available consist of glucocorticoids like oral prednisone for two years or longer and then gradually reduced over the years. A newly established drug called tocilizumab is now used to treat temporal arteritis via injection.
