Fall 2019, Patho Exam 2 Review

WEEK 4 – NERVOUS SYSTEM A. Nervous System a. What makes up the autonomic nervous system? i. The sympathetic and parasympathetic nervous systems ii. What is the parasympathetic nervous system? 1. It conserves energy ...

WEEK 4 – NERVOUS SYSTEM A. Nervous System a. What makes up the autonomic nervous system? i. The sympathetic and parasympathetic nervous systems ii. What is the parasympathetic nervous system? 1. It conserves energy and the body’s resources 2. “Rest and Digest” iii. What is the sympathetic nervous system? 1. Responds to stress by preparing the body to defend itself 2. “Fight or Flight” 3. How does this happen (5)? a. Catecholamines released – epinephrine b. Mobilizes energy stores and increases blood glucose and decreases release of insulin c. Redistributes blood flow and increases muscle perfusion d. Increases diameter of bronchioles in the lungs e. Decreases peristalsis of the GI tract and skin B. Primary Brain Injury a. How are primary brain injuries classified? i. Focal or diffuse b. What are focal brain injuries? i. Specific, grossly observable brain lesions that occur in a precise location ii. Ex: epidural hemorrhage, subdural hemorrhage c. What are diffuse brain injuries? i. Also called multifocal injuries ii. Includes brain injuries due to hypoxia, meningitis, encephalitis, and damage to blood vessels d. What effect does swelling have after a traumatic brain injury (TBI)? i. Can lead to dangerous increases in intracranial pressure ii. REMEMBER: the brain is within a limited space, and increased pressure can cause collateral dysfunction 1. Ex: neurogenic diabetes insipidus – ADH not secreted thus polyuria C. Autonomic Hyperreflexia a. Who is most likely affected by autonomic hyperreflexia? i. Patients that have lesions at the T5-6 level or above b. What is autonomic hyperreflexia characterized by (7)? i. Paroxysmal hypertension (up to 300mm Hg systolic) ii. Pounding headache iii. Blurred vision iv. Sweating above the lesion level with flushing of skin 1. Why does this occur? a. The hypothalamus is unable to regulate body heat because of sympathetic nervous system damage v. Piloerection vi. Nasal congestion vii. Bradycardia (30-40bpm) D. Delirium and Dementia a. Delirium 2 i. What age does delirium occur? 1. Usually older ii. What is the onset? 1. Acute – most common during hospitalizations iii. Are there any associated conditions (9)? 1. UTI 2. Thyroid disorders 3. Hypoxia 4. Hypoglycemia 5. Toxicity 6. Fluid-electrolyte imbalance 7. Renal insufficiency 8. Trauma 9. Multiple medications iv. What is the course? 1. Fluctuating; remits with treatment v. What is the duration? 1. Hours to weeks vi. How is the patient’s attention? 1. Impaired vii. How is their sleep-wake cycle? 1. Disrupted viii. How is their alertness and orientation? 1. Impaired ix. What is their behavior like? 1. Agitated, withdrawn/depressed x. What is their speech like? 1. Incoherent 2. Can be rapid or slowed xi. What are their thoughts like? 1. Disorganized with delusions xii. What are their perceptions like? 1. Hallucinations/illusions b. Dementia i. What age does dementia occur? 1. Usually older ii. What is the onset? 1. Usually insidious 2. Acute in some cases of strokes/trauma iii. Are there any associated conditions (9)? 1. May have no other conditions 2. Brain trauma iv. What is the course? 1. Chronic slow decline v. What is the duration? 1. Months to years vi. How is the patient’s attention? 1. Intact early 3 2. Often impaired late vii. How is their sleep-wake cycle? 1. Usually normal or fragmented viii. How is their alertness? 1. Normal ix. How is their orientation? 1. Intact early 2. Impaired late x. What is their behavior like? 1. Intact early xi. What is their speech like? 1. Word-finding problems xii. What are their thoughts like? 1. impoverished xiii. What are their perceptions like? 1. Usually intact early E. Alzheimer’s Disease a. What is Alzheimer’s Disease i. The leading cause of dementia ii. One of the most common causes of severe cognitive dysfunction in older adults iii. Late onset causes about 90% b. What are risk factors of Alzheimer’s? i. Greatest risk factors are age and family history ii. Other risk factors: diabetes, hypertension, hyperlipidemia, obesity, smoking, depression, cognitive inactivity or low education attainment, female gender, estrogen deficit at the time of menopause, physical inactivity, head trauma, elevated serum homocysteine and cholesterol levels, oxidative stress, and neuroinflammation c. What is the cause of AD? i. Exact cause is unknown and no real understanding of disease process ii. Early onset familial AD is autosomal dominant 1. What gene defects are linked to AD (3)? a. Amyloid precursor protein (APP) on chromosome 21 b. Presenilin 1 (PSEN1) on chromosome 14 c. PSEN2 on chromosome ___ d. How is AD diagnosed? i. FIRST, rule out ALL other causes of dementia F. Stroke a. What is the incidence of stroke? i. Two times higher in blacks than whites ii. Tends to run in families b. What is the most common type or stroke? i. Ischemic – thrombotic or embolic 1. What is the diagnostic cause? a. No identifiable cause established by conventional diagnostics and are classified as “undetermined” or “cryptogenic” c. What are possible outcomes of stroke? i. The mildest outcome can be almost unnoticed 4 ii. The most severe outcomes include hemiplegia, coma, and death d. How are strokes classified? i. According to pathology 1. Ischemic – thrombotic or embolic 2. Global hypoperfusion – as in shock 3. Intracerebral hemorrhage e. What is the most commonly involved artery? i. Middle cerebral artery f. What is the single greatest risk factor for stroke? i. Uncontrolled hypertension g. What are other risk factors for stroke (13)? i. Insulin resistance and diabetes mellitus ii. High total cholesterol or low high-density lipoprotein (HDL) cholesterol level, elevated lipoprotein-A level iii. Hyperhomocysteinemia iv. Congestive heart disease and peripheral vascular disease v. Asymptomatic carotid stenosis vi. Polycythemia and thrombocytopenia vii. Atrial fibrillation viii. Postmenopausal hormone therapy ix. High sodium intake, low potassium intake x. Smoking xi. Physical inactivity xii. Obesity xiii. Chronic sleep deprivation G. Guillain-Barre Syndrome (GBS) a. What is GBS? i. An autoimmune disease triggered by a preceding bacterial or viral infection b. What are first manifestations? i. Numbness, pain, paresthesias, or weakness in the limbs c. How do motor signs manifest? i. As an acute or subacute progressive paralysis ii. Proximal muscles may be involved earlier and more significantly than distal muscles iii. Paresis/paralysis may be present in an ascending pattern involving limbs, respiratory muscles, and bulbar muscles d. How does weakness progress? i. Usually plateaus or improves by the 4th week in 90% of cases 1. After plateau, strength improves over a period of days to months, with the majority reaching levels similar to their pre-disease state ii. Respiratory weakness leads to need for ventilator support in 10-30% of cases iii. Cranial nerve weakness manifests as facial weakness and bulbar weakness in chewing, swallowing, and coughing H. Multiple Sclerosis a. What is MS? i. A chronic inflammatory disease involving degeneration of CAN myelin, scarring or formation of plaque, and loss of axons 5 b. What is the cause of MS? i. An autoimmune response to self-antigens in genetically susceptible individuals c. What is the first demyelinating event? i. AKA “clinically isolated syndrome” ii. A single episode of neurologic dysfunction lasting greater than 24 hours that can be a prelude to MS d. Are there replases or remissions? i. Initially, 90% present with remissions and exacerbations ii. 10% present with a primary progressive course iii. 90% will develop a progressive course 10-20 years after onset iv. Once walking problems develop, progression occurs quickly regardless of type I. Myasthenia Gravis a. What is MG? i. A chronic autoimmune disease mediated by acetylcholine receptor (AchR) antibodies that act at the neuromuscular junction b. What is the onset? i. Typically insidious c. What do clinical manifestations begin? i. May first appear during pregnancy, postpartum period ii. In conjunction with administration of certain anesthetic agents d. What are hallmark symptoms (2)? i. Exertional fatigue ii. Weakness that worsens with activity, improves with rest, and recurs with resumption of activity e. What are typical complaints? i. Fatigue after exercise ii. Recent history of recurring upper respiratory tract infections f. What muscles are affected? i. Muscles of the eyes, face, mouth, throat, and neck are affected first ii. What muscles are most affected? 1. Extraocular muscles and levator muscles 2. What are manifestations of this (3)? a. Diplopia b. Ptosis c. Ocular palsies iii. What muscles are next most involved? 1. Muscles of facial expression, mastication, swallowing, and speech g. What are later signs of disease progression? i. Respiratory distress and difficulty breathing J. Parkinson’s Disease a. What is the pathogensis of PD? i. Unknown ii. Several genes have been identified iii. What is the primary pathology? 1. Degeneration of basal ganglia (corpus striatum, globus pallidus, subthalamic nucleus, substantia nigra) iv. What are hallmark pathologic features? 1. Loss of dopaminergic pigmented neurons 6 2. Dopamine loss includes: brainstem, thalamus, and cortex b. What are classic motor manifestations (5)? i. Resting tremor ii. Pill-rolling tremors iii. Bradykinesia/akinesia (poverty of movement) iv. Rigidity (muscle stiffness) v. Postural abnormalities c. What is the characteristic appearance? i. Wide-eyes, unblinking, staring expression with facial muscles smoothed out and almost immobile ii. Saliva frequently drools iii. Skin of face is frequently greasy iv. Gait is pathognomonic: individual walks with slow, short, shuffling steps; arms are flexed, abducted, and held stiffly at side; and trunk is bent slightly forward 1. Person may break into a run spontaneously or when pushed forward or backward v. Tendency is to fall to the side d. What are some of the most common depressing symptoms (3)? i. Postural instability ii. Sleep disorders iii. Difficulty concentrating K. Pain a. Acute Pain i. What is a characteristic experience? 1. An event ii. What is the source of pain? 1. External agent or internal disease usually known iii. What is the onset? 1. Usually sudden iv. What is the duration? 1. Transient but up to 6 months v. What are the clinical signs (5)? 1. Increased pulse rate 2. Elevated blood pressure 3. Increased respiratory rate 4. Diaphoresis 5. Dilated pupils vi. What is the clinical course? 1. Suffering but usually decreases over time vii. What is the prognosis? 1. Likelihood of eventual complete relief b. Chronic Pain i. What is a characteristic experience? 1. A situation; state of existence ii. What is the source of pain? 1. Unknown 2. If known, treatment is prolonged or ineffective 7 iii. What is the onset? 1. May be sudden or develop insidiously iv. What is the duration? 1. Prolonged and persistent (months to years) v. What are the clinical signs? 1. Response patterns vary 2. Fewer overt signs (adaptation) vi. What is the clinical course? 1. Suffering usually increases over time vii. What is the prognosis? 1. Complete relief usually not possible c. Neuropathic Pain i. What is neuropathic pain? 1. Chronic pain initiated or caused by a primary lesion or dysfunction in the nervous system and leads to long-term changes in pain pathway structures (neuroplasticity) and abnormal processing of sensory information ii. What happens to the pain experienced? 1. It is amplified without stimulation by injury or inflammation iii. How is it described? 1. Burning, shooting, shock-like, or tingling iv. What are the characteristics? 1. Hyperalgesia 2. Increased sensitivity to a normally painful stimulus (touch, pressure, pinprick, cold, and heat) 3. Allodynia – the induction of pain by normally nonpainful stimuli L. Headaches a. Migraine (with or without aura) i. What is the age of onset? 1. Childhood, adolescence, or young adulthood ii. What is the common gender affected? 1. Female iii. Is there a family history of headaches? 1. Yes iv. What is the onset and evolution? 1. Slow to rapid v. What is the time course? 1. Episodic vi. What is the quality? 1. Usually throbbing vii. What is the location? 1. Variable, often unilateral viii. Are there any associated features (2)? 1. Prodrome 2. Vomiting b. Cluster headache/Proximal hemicrania i. What is the age of onset? 1. Young adulthood, middle age