Step I CNS path q

[MudPhud20XX]

A 48-year-old woman has experienced headaches for the past week. On physical examination her temperature is 37.6° C (99.7° F), pulse 73 bpm, respirations 16 bpm, and blood pressure 130/85 mmHg. She has a lumbar puncture performed. The cerebrospinal fluid (CSF) opening pressure is 220 mm H2O, the CSF protein 60 mg/dL, and the CSF glucose 75 mg/dL (serum glucose 105 mg/dL). A CT scan shows the findings in the image. Biopsy of the mass reveals gliosis and fibrosis with necrosis, neutrophils, and lymphocytes. Which of the following is the most likely diagnosis?

 

[MudPhud20XX]

A 23-year-old man develops ascending paralysis after recovering from an atypical pneumonia. A spinal tap reveals an increase in spinal fluid protein and lymphocytes. The glucose is normal. Which cell type is damaged in this disorder?

 

[MudPhud20XX]

A 6-year-old boy is brought in to see his pediatrician by his mother, who reports that he has been walking strangely and falling down more over the past 6 months. On examination, he is found to have a hemangioblastoma in his right eye. On which chromosome does the gene responsible for this boy’s condition most likely reside?

 

[MudPhud20XX]

A 27-year-old pregnant woman visits an obstetrician for routine prenatal care, and reveals that she has forgotten to take folic acid supplements daily. Concerned about this, her physician orders some blood tests which reveal an elevated α-fetoprotein. When the baby is born 3 months later, a tuft of hair is found over the lumbar section of the vertebral column. No signs of increased intracranial pressure (i.e., papilledema) or other abnormalities are noted. What neural tube defect is likely present in this baby?

 

[MudPhud20XX]

An 8-year-old boy is brought to see a physician by his parents, who report that he has had some weakness in the past week. Initially, he had difficulty walking, and he now has difficulty lifting his arms as well. He has also been complaining of a tingling sensation in his fingers and toes. On examination, he is found to have diminished biceps and patellar reflexes bilaterally and decreased sensation on his hands and feet, but normal mental status, no papilledema, and he is afebrile. What likely preceded the onset of this boy’s neurological symptoms?

 

[MudPhud20XX]

A 65-year-old retired airline pilot, who had a past history of chronic ischemic heart disease, died suddenly of a myocardial infarction. Mental function prior to his demise was normal. At autopsy the brain had a reduced weight (see figure). Sections through the cerebral cortex revealed deeply eosinophilic neurons, some of which contained remnants of pyknotic-appearing nuclear material. There was no inflammatory infiltrate or evidence of acute injury. What is the most likely cause of the changes in the brain?

 

[Transposony]

A 65-year-old retired airline pilot, who had a past history of chronic ischemic heart disease, died suddenly of a myocardial infarction. Mental function prior to his demise was normal. At autopsy the brain had a reduced weight (see figure). Sections through the cerebral cortex revealed deeply eosinophilic neurons, some of which contained remnants of pyknotic-appearing nuclear material. There was no inflammatory infiltrate or evidence of acute injury. What is the most likely cause of the changes in the brain?

Chronic hypoxic-ischemic encephalopathy

 

[MudPhud20XX]

right on!

The brain shows narrow gyri and sulci indicating cerebral atrophy. Sections through the cerebral cortex showed deeply eosinophilic neurons, some of which contained nuclear remnants. These are apoptotic neurons or "red neurons" and are most often due to chronic ischemia of the brain, which is most often caused by atherosclerosis of the internal carotid arteries and/or middle cerebral arteries. Loss of these neurons in layers 3, 5, and 6 diminishes the mass of the cerebral cortex causing narrow gyri and sulci.

 

[lunalight]

A 23-year-old man develops ascending paralysis after recovering from an atypical pneumonia. A spinal tap reveals an increase in spinal fluid protein and lymphocytes. The glucose is normal. Which cell type is damaged in this disorder?

This is GBS, so T cells?
Edit: Its late and I forgot that in GBS the immune attack doesn't have to be just on myelin, it can be on the Schwann cells too and sometimes the axons themselves.

A 6-year-old boy is brought in to see his pediatrician by his mother, who reports that he has been walking strangely and falling down more over the past 6 months. On examination, he is found to have a hemangioblastoma in his right eye. On which chromosome does the gene responsible for this boy’s condition most likely reside?

VHL gene is on chromosome 3 (I think!)

A 27-year-old pregnant woman visits an obstetrician for routine prenatal care, and reveals that she has forgotten to take folic acid supplements daily. Concerned about this, her physician orders some blood tests which reveal an elevated α-fetoprotein. When the baby is born 3 months later, a tuft of hair is found over the lumbar section of the vertebral column. No signs of increased intracranial pressure (i.e., papilledema) or other abnormalities are noted. What neural tube defect is likely present in this baby?

Spina bifida occulta

An 8-year-old boy is brought to see a physician by his parents, who report that he has had some weakness in the past week. Initially, he had difficulty walking, and he now has difficulty lifting his arms as well. He has also been complaining of a tingling sensation in his fingers and toes. On examination, he is found to have diminished biceps and patellar reflexes bilaterally and decreased sensation on his hands and feet, but normal mental status, no papilledema, and he is afebrile. What likely preceded the onset of this boy’s neurological symptoms?

This is Charcot-Marie-Tooth, so I want to say foot drop, but not sure if that counts as a neurological symptom. If it does, then I have no idea what the answer is, lol

 

[MudPhud20XX]

This is GBS, so T cells?
Edit: Its late and I forgot that in GBS the immune attack doesn't have to be just on myelin, it can be on the Schwann cells too and sometimes the axons themselves. --> correct

The patient has developed Guillain-Barré syndrome (GBS) after recovering from a Mycoplasma pneumoniae atypical pneumonia. GBS is the most common acute peripheral neuropathy and is an autoimmune demyelination syndrome involving peripheral and spinal nerves. Schwann cells are the primary cells for synthesizing myelin. GBS is characterized by a rapidly progressive ascending (sometimes descending) motor weakness. There is a danger of respiratory muscle paralysis and death. Spinal fluid shows increased protein and lymphocytes; however, glucose is normal. Treatment involves use of plasmapheresis. Most patients recover after a few weeks to months with or without permanent disability.




VHL gene is on chromosome 3 (I think!) --> correct



Spina bifida occulta --> correct



This is Charcot-Marie-Tooth, so I want to say foot drop, but not sure if that counts as a neurological symptom. If it does, then I have no idea what the answer is, lol

--> correct good job

 

[MudPhud20XX]

An 8-year-old boy is brought to see a physician by his parents, who report that he has had some weakness in the past week. Initially, he had difficulty walking, and he now has difficulty lifting his arms as well. He has also been complaining of a tingling sensation in his fingers and toes. On examination, he is found to have diminished biceps and patellar reflexes bilaterally and decreased sensation on his hands and feet, but normal mental status, no papilledema, and he is afebrile. What likely preceded the onset of this boy’s neurological symptoms?

 

[Mr. Mojo Risin]

An 8-year-old boy is brought to see a physician by his parents, who report that he has had some weakness in the past week. Initially, he had difficulty walking, and he now has difficulty lifting his arms as well. He has also been complaining of a tingling sensation in his fingers and toes. On examination, he is found to have diminished biceps and patellar reflexes bilaterally and decreased sensation on his hands and feet, but normal mental status, no papilledema, and he is afebrile. What likely preceded the onset of this boy’s neurological symptoms?

What is... C. jejuni infection, Alex?

 

[MudPhud20XX]

This boy has Guillain-Barré syndrome, a peripheral neuropathy characterized by ascending muscle weakness. This autoimmune condition is typically preceded by an infection, often viral.

GBS can be caused by Campylobacter jejuni or CMV

What is... C. jejuni infection, Alex?

 

[MudPhud20XX]

A 57-year-old man goes to see a neurologist for a 6-month history of significant weight loss and difficulty swallowing. On examination, he is noted to have an absent gag reflex and difficulty elevating his shoulders and turning his head against resistance. In light of the significant weight loss, the neurologist feels that this man may have a malignant brain tumor. A tumor at what cranial foramen would cause these findings?

 

[lunalight]

This boy has Guillain-Barré syndrome, a peripheral neuropathy characterized by ascending muscle weakness. This autoimmune condition is typically preceded by an infection, often viral.

GBS can be caused by Campylobacter jejuni or CMV

I'm confused...is this the same one I answered? I thought he had CMT...

 

[Mr. Mojo Risin]

A 57-year-old man goes to see a neurologist for a 6-month history of significant weight loss and difficulty swallowing. On examination, he is noted to have an absent gag reflex and difficulty elevating his shoulders and turning his head against resistance. In light of the significant weight loss, the neurologist feels that this man may have a malignant brain tumor. A tumor at what cranial foramen would cause these findings?

Jugular foramen

 

[MudPhud20XX]

I'm confused...is this the same one I answered? I thought he had CMT...

it's the answer for the below question

An 8-year-old boy is brought to see a physician by his parents, who report that he has had some weakness in the past week. Initially, he had difficulty walking, and he now has difficulty lifting his arms as well. He has also been complaining of a tingling sensation in his fingers and toes. On examination, he is found to have diminished biceps and patellar reflexes bilaterally and decreased sensation on his hands and feet, but normal mental status, no papilledema, and he is afebrile. What likely preceded the onset of this boy’s neurological symptoms?

 

[MudPhud20XX]

Jugular foramen

correct.

This man’s difficulty swallowing and absent gag reflex suggest that cranial nerves IX and X are affected, and the impaired shoulder lifting and head turning suggest that cranial nerve XI is affected as well. These three nerves all exit the cranium through the jugular foramen.

 

[MudPhud20XX]

A 34-year-old man has polydipsia and polyuria. With the patient fasting, a 24-hour urine sample shows a volume of 7.8 L and osmolality of 135.0 mOsmol/kg, while the plasma osmolality is 270.0 mOsmol/kg. His urine is negative for red blood cells, leukocytes, protein, and glucose. His blood pressure and heart rate are both normal. What is a likely cause of polyuria in this patient?