RECOMENDACIONES

 One out-of-place congenital problem:

 Neural tube defects:

 associated w/ high levels of alpha fetoprotein in the amniotic fluid and maternal serum. Their incidenc is decreased w/ maternal folate ingesting during pregnancy

 Spina bifida occulta:

• failure of bony spinal canal to close, but no structural herniation. Usually seen in lower vertebral levels in association w/ tuft of hair (associated with increased levels of AFP)

 Meningocele:

• meninges herniate through spinal defect

 Meningomyelocele:

• meninges and spinal cord herniate through spinal canal defect

 Anencephaly: no development

 Concussion:

 Transient paralysis of cerebral function immediately after head trauma

 Manifested by dizziness, cold perspiration, visual disturbance & loss of consciousness

 Most people recover completely w/in a few hours or days

 Contusion:

 Bruise of the brain parenchyma typically involving the subunit of the gyrus

 Brain Tumors

 Adult

 70% above Tentorium (i.e. cerebral hemispheres)

 Incidence: Metastases > Astrocytoma (including glioblastoma) > Meningioma

 Child

 70% below Tentorium (i.e. cerebellum)

 Incidence: Astrocytoma > Medulloblastoma > Ependymoma

 Subdural head injury:

 Traumatic subdural hematomas are among the most lethal of all head injuries, common during abuse cases

 See in 15% of head traumas

 Tiny “bridging veins” running between brain surface & its outer covering stretch & tear, allowing blood to collect

 These veins rupture due to sudden change in velocity of head during trauma

 Signs/symptoms – confusion, headaches, disorientation, fluctuating levels of consciousness or coma

 Develop gradually over time, occurring several hours or even days after initial injury

 Intracranial hemorrhage:

 Epidural hematoma

 Rupture of middle meningeal artery, often secondary to fracture of temporal bone

 Lucid interval; CT shows biconcave disk not crossing suture lines

 Subdural hematoma

 Rupture of bridging veins.

 Venous bleeding (less pressure) w/ delayed onset of symptoms.

 Seen in elderly individuals, alcoholics, and blunt trauma.

 Crescent shaped hemorrhage that crosses suture lines

 Pt lapses into a coma and fluctuating levels consiousness hours after blunt trauma→dx: subdural hematoma

 Subarachnoid hemorrhage

 Rupture of an aneurysm (usually Berry aneurysm) or AV malformation

 Patient complains of “worst headache of my life”

 Bloody or xanthochromic spinal tap

 Berry aneurysms:

• Aka “saccular aneurysms”

• Most common cause of nontraumatic subarachnoid hemorrhage

• 90% are in the anterior part of the circle of Willis

♦ MOST common site is the anterior communicating artery (Or branch of the middle cerebral)

 In the past, middle meningeal

• Rupture, is the most common complication, causes severe headache, and leads to hemorrhagic stroke

• Associated with adult polycystic kidney disease, Ehlers-Danlos syndrome, and Marfan’s syndrome

• May result in cerebrovascular accident

 Parenchymal Hematoma

 Caused by HTN, amyloid angiopathy, DM, and Tumor

 Meningioma:

 Intracranial tumor arising from arachnoid, usually occurring in adults >30 y.o.

 Cerebral infarction (stroke):

 Infarction of cerebrum due to arterial occlusion by a thrombus or embolus from the heart or carotid artery

 Common signs/symptoms – sudden paralysis & numbness on one side of body

 Encephalitis:

 An uncommon inflammation of the brain

 Most commonly caused by VIRAL infection –Like HSV

 Exposure to viruses via:

 Insect bites, food/drink contamination, inhalation of respiratory droplets, skin contact

• In rural settings – arboviruses carried by mosquitos or ticks or that are accidentally ingested

• In urban settings – enteroviruses are most common (Coxsackie virus, poliovirus, & echovirus)

 Other causes:

 HSV, varicella, measles, mumps, rubella, adenovirus, rabies, West Nile virus

 Once virus is in blood it can localize in brain tissue causing inflammation

 WBCs invade to try to fight off infection – brain swells – can cause destruction of nerve cells, bleeding & brain damage

 Symptoms – fever, headache, vomiting, photophobia, stiff neck/back, confusion (disorientation, drowsiness, clumsiness)

 Meningitis:

 Brain & spinal cord meninges become inflamed

 May be bacterial OR may be caused by a number of viruses (Echovirus, Coxsackie, Mumps, etc.)

 Bacteria are the most common cause of Meningitis – think Neisseria meningitides is BActeria

• Don’t get clowned, because Encephalitis is from VIRAL

 Viral meningitis rarely results in permanent neural damage

 CSF Findings in Meningitis

 Type Pressure Cell Type Protein Sugar

 Bacterial Up PMNs Up Up Down

 Fungal/TB Up Lymphos Up Up Down

 Viral Normal/Up Lymphos Up Normal Normal

 May be transferred by respiratory droplets

 Most common in adults – Neisseria meningitidis & S. pneumoniae (elderly)

• N. meningitidis:

♦ Transmission via respiratory droplets

♦ Key virulence factor in N. meningitidis is its antiphagocytic capsule, same as S. Pneumoniae

♦ IgA protease also in an important virulence factor

♦ Treat it w/ PEN G

 Most common in children < 2 y.o. – H. influenzae

 Most common in adults – Neisseria meningitidis & S. pneumoniae

 Most common in the elderly – S. pneumoniae

• NOTE all 3 of the most common have Capules

 Common Causes of Meningitis

 Newborn (0-6 m)  Group B Strep, E. coli, Listeria

• Listeria Monocytogenes might cause Fetal Death or meningitis (Think the baby goes LISTless)

 Don’t confuse with Floppy baby (Botulism)

♦ Also causes Dysentery, Cholera, and Gastroenteritis

 Children (6 m – 6y) S. pneumoniae, N. meningitidis, H. influenza B, Enteroviruses

 Adults (6y – 60y)  N. meningitides, Enteroviruses, S. pneumoniae, HSV

 Adults (60+)  S. pneumoniae (#1 in eldely), Gram – rods, Listeria

 Infecting organism enters body through nose & throat

 Signs & symptoms – high fever, severe headache, & neck stiffness

 Arnold-chiari Malformation

 Brain coming through Foramen Magnum

 Syringomyelia

 Softening and cavitation around central canal of spinal cord

 Crossing fibers of spinothalamic tract are damaged

 Bilateral loss of pain and temperature sensation in upper extremities with preservation of touch sensation

 Most common C8-T1

 Common in Arnold Chiari malformation

 Tabes Dorsalis

 Degeneration of dorsal columns and dorsal roots due to tertiary syphilis, resulting in impaired proprioception and locomotor ataxia

 Associated with Charcot joints, shooting lightening pain, Argyll-Robertson pupils, and absence of deep tendon reflexes

 One out-of-place disorder:

 Fetal alcohol syndrome:

 Newborns of moms who consumed significant amounts of alcohol (teratogen) during pregnancy (highest risk at 3-8 wks)

 Have increased incidence of congenital abnormalities, including pre- & postnatal developmental retardation, microcephaly, facial abnormalities, limb dislocation, and heart and lung fistulas

 Mechanism may include inhibition of cell migration

 The #1 cause of congenital malformations in the U.S.