פרק 40- Chapter 40 Diseases of the Nervous System Caused by Nutritional Deficiency Flashcards
Table 40-1
CLINICAL FINDINGS IN NUTRITIONAL POLYNEUROPATHY
Table 40-2
MECHANISMS WHEREBY MALABSORPTION MAY BE RELATED TO NEUROLOGIC DISEASE
Table 40-3
VITAMIN-RESPONSIVE INHERITED DISORDERS AFFECTING THE NERVOUS SYSTEM (6)
Thiamine (B1) (4)
Pyridoxine (B6) (3)
Cobalamin (B12) (2)
Folic acid. (3)
Biotin (2)
Nicotinamide (1)
מהם האזורים העיקריים הנפגעים בניוון צרבלרי אלכוהולי
(alcoholic cerebellar degeneration) ?
א. Dentate nucleus and the triangle of Guillain Mollaret
ב. Vermis and anterior lobes of cerebellum
ג. Flocculonodulus .
ד. Purkinie fibers at the inferior aspect of cerebellum
Vermis and anterior lobes of cerebellum
Alcoholic” Cerebellar Degeneration
הביטוי מתייחס לניוון ורמיס ואונות קדמיות של הצרבלום באלכוהוליסטים. בעבר השיעור היה כפול משל מחלת וורניקה, וכמוהו – שכיח בהרבה בגברים. מאופיין בהליכה על בסיס רחב, דרגה משתנה של אטקסיה טרונקלית ושל הרגליים; הידיים פגועות פחות ולרוב בכלל לא. ניד ודיסארתריה אינם שכיחים. בנוסף נראה רעד אטקטי (אינטנציונלי), וכן רעד תנוחתי בידיים הדומה לאחד הסוגים הפרקינסונים. האטקסיה הטרונקלית מאופיינת בנדנוד בתדירות ספציפית של 2-3 הרץ בכיוון אנטרו-פוסטריורי. הסימפטומים מתפתחים על פני שבועות-חודשים, ואז נשארים קבועים שנים רבות. לעיתים המהלך הוא של החמרות סביב זיהום\התקף דליריום טרמנס.
פתולוגיה – ניוון של כל המרכיבים הנוירו-צלולרים של קורטקס הצרבלום, ובמיוחד של תאי פורקינייה באספקטים אנטריורי וסופריורי של הורמיס.
בהדמיה רואים אטרופיה צרבלרית
ישנן 2 צורות שחשוב לשים אליהן לב:
1) התייצגות המוגבלת לאי יציבות של עמידה והליכה; השינויים הפתולוגים במקרה זה מוגבלים לחלק אנטרו-פוסטיורי של הורמיס.
2) צורה חריפה וחולפת, ופרט לכך זהה למאפייני הצורה הכרונית.
צורות אלה, ובעיקר הצורה החולפת, זהים להתייצגות הצרבלרית של מחלת וורניקה (פתולוגית וקלינית). ואכן, לדעת אדאמס, הם מייצגים אותו תהליך מחלה (אלא שבמחלת וורניקה יש גם התייצגות אוקולרית וקוגניטיבית, ובהתנוונות האלכוהולית הצרבלריות מבודדת וכרונית).
הסיבה להתנוונות הצרבלרית היא כמעט בוודאות חסרים תזונתיים (ולא אפקט טוקסי של אלכוהול), וספציפית של תיאמין (לבד או כגורם עיקרי), לאור השיפור הנראה באטקסיה תחת טיפול בויטמינים.
עוד תופעות הקשורות לחסרים תזונתיים ואלכוהול
תיאור קליני של מטופל עם הפרעה בעמודות האחוריות.
באיזה מעגל ביוכימי תהיה הפרעה?
1. heme
2. cobalamine
3. tocopherol
Cobalamin= b12
- The spinal cord, brain, optic nerves, and peripheral nerves are all affected by vitamin B12 (cobalamin) deficiency, giving rise to a classic neurologic syndrome. The spinal cord is usually affected first and often exclusively. The term subacute combined degeneration (SCD) is customarily reserved for the spinal cord lesion of vitamin B12 deficiency and serves to distinguish it from other types of spinal cord diseases that happen to involve the posterior and lateral columns.
- The nervous system involvement in
SCD is roughly symmetrical and distal, and sensory disturbances precede the motor ones
Loss of vibration sense is the most consistent sign; it is more pronounced in the feet and legs than in the hands and arms and frequently extends over the trunk. Position sense is usually impaired in parallel. The motor signs, usually limited to the legs, include a mild symmetrical loss of strength in proximal limb muscles, spasticity, enhanced tendon reflexes, clonus, and extensor plantar Responses. -
Cognitive symptoms and signs are frequent, ranging from irritability, apathy,
somnolence, suspiciousness, and emotional instability to a marked confusional or depressive psychosis or dementia. - Visual impairment caused by optic neuropathy occasionally may be an early or sole manifestation of pernicious anemia; examination discloses roughly symmetrical centrocecal scotomata and optic atrophy in the most advanced cases.
- CSF – NAD or protein elevated
- NCS – slowing conduction and reduced sensory potentials though may be normal at first
- MRI – T2 hyperintensity of posterior columns
מה מהבאים לא שכיח בחסר ויטמין
B12?
א. אטקסיה צרבלרית
ב. נוירופתיה
ג. פגיעה בתחושת ויברציה
ד. סימנים פירמידלים
לא תהיה אטקסיה צרבלרית
- The spinal cord, brain, optic nerves, and peripheral nerves are all affected by vitamin B12 (cobalamin) deficiency, giving rise to a classic neurologic syndrome. The spinal cord is usually affected first and often exclusively. The term subacute combined degeneration (SCD) is customarily reserved for the spinal cord lesion of vitamin B12 deficiency and serves to distinguish it from other types of spinal cord diseases that happen to involve the posterior and lateral columns.
- The nervous system involvement in
SCD is roughly symmetrical and distal, and sensory disturbances precede the motor ones
Loss of vibration sense is the most consistent sign; it is more pronounced in the feet and legs than in the hands and arms and frequently extends over the trunk. Position sense is usually impaired in parallel. The motor signs, usually limited to the legs, include a mild symmetrical loss of strength in proximal limb muscles, spasticity, enhanced tendon reflexes, clonus, and extensor plantar Responses. -
Cognitive symptoms and signs are frequent, ranging from irritability, apathy,
somnolence, suspiciousness, and emotional instability to a marked confusional or depressive psychosis or dementia. - Visual impairment caused by optic neuropathy occasionally may be an early or sole manifestation of pernicious anemia; examination discloses roughly symmetrical centrocecal scotomata and optic atrophy in the most advanced cases.
- CSF – NAD or protein elevated
- NCS – slowing conduction and reduced sensory potentials though may be normal at first
- MRI – T2 hyperintensity of posterior columns
חולה הסובלת ממיאסטניה גראביס וויטיליגו מתלוננת על חוסר יציבות. בבדיקתה רומברג חיובי, ערות החזרים, הפרעה בתחושה עמוקה. איך תטפל
א. סטרואידים
ב. פירידוקסין
ג. ויטמין E
ד. B12
B12
Picture suggestive fo combined subacute degeneration of spinal cord – B12 deficiency.
קצת על המסיחים האחרים-
א. Steroids – not indicated as does not sound like an exacerbation of MG.
ב. B6 - associated with INH – neuropathy- painful sensorimotor neuropathy, loss of
Reflexes. Also associated with homocysteinemia – which in excess can lead to vascular thrombosis.
* In B6 toxicity – paradoxical sensory neuropathy, ganglionopathy, no weakness, ataxia and areflexia, purely sensory,
ג. Vit E: spinocerebellar syndrome, ataxia, areflexia, opthalmoparesis, Retinitis pigmentosa, muscle weakness and raised CPK.
אחות חדר ניתוח, צמחונית, סובלת מחולשה וערות החזרים. מדוע?
1. exposure to Nitric oxide
2. exposure to halothane
3. exposure to Carbon monoxide
Exposure to nitric oxide!
Uncommon instances of vitamin B12 deficiency are observed in lactovegetarians and in infants nursed by mothers deficient in vitamin B12; vitamin B12 deficiency may also be a result of a rare genetic defect of methyl malonyl-CoA Mutase as discussed further on.
It should be further commented that interference with methionine synthetase, a methyl cobalamin-dependent Enzyme, can be produced by exposure to nitrous Oxide. Chronic exposure can produce the entire subacute combined syndrome but more often, an individual is marginally deficient, often but not always elderly, and even short exposure may then induce symptoms. A megaloblastic anemic state, as well as the neurologic features of SCD, is thereby induced by the gas. This illness, cleverly named “anesthesia paresthetica“ by Kinsella and Green, arises in operating room personnel (we have seen it in several anesthesia nurses), occasionally in dentists, and in abusers of the gas (whippets) to obtain a “high.” Their serum B12 levels are usually in the low-normal range, and measurements of methylmalonic acid are greatly elevated (see further on).
High serum concentrations of cobalamin metabolites, methylmalonic Acid (normal range, 73 to 271 nmol/L), and *homocysteine (normal range 5.4 to 16.2 mmol/L) are additional reliable indicators of an intracellular cobalamin deficiency and can be used to corroborate the diagnosis in cases of low-mid-range B12 levels.
בן 46 עם מחלת קרוהן הכוללת מעורבות ה-
terminal ileum
מפתח פרסתזיות ברגליים והפרעה בהליכה, ובבדיקתו נמצאו העדר החזרי אכילס וסימן ע”ש בבינסקי דו-צדדי. תחושת רטט חסרה
בבהונות ובקרסוליים. איזו הפרעה המטבולית אופיינית במצב זה?
א. ירידה ב- methylmalonyl-CoA .
ב. עלייה ב- propionyl-CoA .
ג. ירידה ב- homocysteine .
ד. עלייה ב- methionine
עלייה ב
Proprionyl Co-A
lack of the cobalamin-dependent enzyme methylmalonyl-CoA mutase leads to the accumulation of methylmalonyl-CoA and its precursor, propionyl-CoA. According to this mechanism, propionyl-CoA displaces succinyl-CoA, which is the usual primer for the synthesis of even-chain fatty acids; this results in the anomalous insertion of odd-chain fatty acids into membrane lipids, such as are found in myelin sheaths. Conceivably, this biochemical abnormality underlies the lesions of myelinated fibers that characterize the disease. However, Carmel and associates described a hereditary form of cobalamin
deficiency in which methylmalonylCoA
mutase activity was normal, despite the presence of typical neurologic abnormalities. In their view, the primary failure is one of methylation of homocysteine to methionine, that is, a failure of the methionine synthetase reaction, for which the coenzyme methylcobalamin is necessary.
או במילים אחרות- שני הסברים להפרעה:
1. בעיה במתילמלוניל קו א מוטאז=> הצטברות של
מתילמלוניל קו איי + פרופריוניל קו איי
2. כשל במתליציה של הומוציסטאין למתיונין=> הצטברות של הומוציסטאין.
בן 41 לאחר ניתוח מעיים. תלונות של אי ציצבות בהליכה. בבדיקה- הגבלה בתנועות עיניים, אטקסיה. בבדיקה גנטית- חסר באנזים
tocopherol
איזה טיפול יעזור?
1.Vitamin E
2. Vitamin B1
3. Vitamin B12
4. Vitamin B6
Vitamin E
Vitamin E Deficiency
This occurs in 2 types: a defect in intestinal absorption** and an inherent
hepatic enzyme deficiency that blocks incorporation of vitamin E into lipoprotein. A rare neurologic disorder of childhood, sometimes later in life, consisting essentially of spinocerebellar degeneration in association with polyneuropathy and pigmentary retinopathy, has been attributed to a deficiency of vitamin E consequent to prolonged intestinal fat malabsorption.
*Ataxia, loss of tendon reflexes, ophthalmoparesis, proximal muscle weakness with elevated serum creatine kinase, and decreased sensation are the usual manifestations of vitamin E deficiency.
In affected children, neurologic function improves after long-term daily
supplementation with high doses of vitamin E. In recent years there have been reports of a form of spinocerebellar degeneration attributable to an inherited but conditioned deficiency of vitamin E that may closely mimic the phenotype of Friedreich ataxia. The onset is usually in early adolescence, but there is variability, particularly among different families. In these patients, absorption and transport of vitamin E to the liver is normal, but hepatic incorporation of tocopherol (the active form of vitamin E) into very-low-density lipoproteins is defective (Traber et al). The abnormality has been traced to a mutation in TTPA, the gene encoding a-tocopherol transfer protein (Gotoda et al). In a sense, this is a vitamin deficiency conditioned by a genetic mutation. An important feature of these cases is that chronic oral administration of large doses of vitamin E can halt and even reverse progression of the ataxia
—-
קצת על המסיחים הנוספים:
* B1 Korsakoff
* B12- SCD
B6= Pyridoxine deficiency or excess has been associated with a sensory polyneuropathy. the occurrence of neuropathy caused by INH was recognized in the early 1950s, doon after the introduction of this drug for the treatment of tuberculosis.
pyridoxine deficiency also leads to homocystinemia because the vitamin is a coenzyme for the conversion of homocysteine to cystathionine. vascular thrombosis may result from the excess homocysteine. sever pyridoxine deficiency in animals and humans also causes seizures.
תסמונת הכוללת ניוון ספינו-צרבלרי
spinocerebellar degeneration
פולינוירופתיה ורטינופתיה פיגמנטרית
pimentary retinopathy.
חסר כרוני באחד הויטמינים הבאים עלול לגרום לתסמונת זו:
א. tocopherol
ב. thiamine
ג. riboflavin
ד. pyridoxine
Vitamin E= tocopherol
Vitamin E Deficiency
This occurs in 2 types: a defect in intestinal absorption** and an inherent
hepatic enzyme deficiency that blocks incorporation of vitamin E into lipoprotein. A rare neurologic disorder of childhood, sometimes later in life, consisting essentially of spinocerebellar degeneration in association with polyneuropathy and pigmentary retinopathy, has been attributed to a deficiency of vitamin E consequent to prolonged intestinal fat malabsorption.
*Ataxia, loss of tendon reflexes, ophthalmoparesis, proximal muscle weakness with elevated serum creatine kinase, and decreased sensation are the usual manifestations of vitamin E deficiency.
In affected children, neurologic function improves after long-term daily
supplementation with high doses of vitamin E. In recent years there have been reports of a form of spinocerebellar degeneration attributable to an inherited but conditioned deficiency of vitamin E that may closely mimic the phenotype of Friedreich ataxia. The onset is usually in early adolescence, but there is variability, particularly among different families. In these patients, absorption and transport of vitamin E to the liver is normal, but hepatic incorporation of tocopherol (the active form of vitamin E) into very-low-density lipoproteins is defective (Traber et al). The abnormality has been traced to a mutation in TTPA, the gene encoding a-tocopherol transfer protein (Gotoda et al). In a sense, this is a vitamin deficiency conditioned by a genetic mutation. An important feature of these cases is that chronic oral administration of large doses of vitamin E can halt and even reverse progression of the ataxia
—-
קצת על המסיחים הנוספים:
* B1= thiamine- Korsakoff
* B2= riboflavin- night blindness and lipid storage myopathy.
B6= Pyridoxine deficiency or excess has been associated with a sensory polyneuropathy. the occurrence of neuropathy caused by INH was recognized in the early 1950s, doon after the introduction of this drug for the treatment of tuberculosis.
pyridoxine deficiency also leads to homocystinemia because the vitamin is a coenzyme for the conversion of homocysteine to cystathionine. vascular thrombosis may result from the excess homocysteine. sever pyridoxine deficiency in animals and humans also causes seizures.
בת 20 מגיעה למיון עם אטקסיה, הליכה על בסיס רחב, הפרעה בתנועות עיניים הוריזונטליות, בלבול.
בMRI DWI-
היפראינטנסיות בתלמוס מדיאלי דו”צ. מה הצעד האבחנתי הבא?
א. רמת טרנסקטולאז בדם
ב. אנגיוגרפיה
ג. רמת אלכוהול.
רמת טרנסקטולאז בדם.
The acute lesions of the Wernicke-korsakoff syndrome in the mammillary bodies, and other medial thalamic and periaqueductal areas can be demonstrated in most cases by magnetic resonance imaging (MRI). The changes are most apparent on FLAIR, T2, and diffusion-weighted sequences (if there is hemorrhage), but they may also enhance.
Measurements of serum thiamine and red blood cell transketolase have been explored as aids to diagnosis but are not sufficiently sensitive for clinical use and they are not readily available. Before treatment with thiamine, patients with Wernicke disease show a marked reduction in transketolase.
Patients who die in the acute stages of Wernicke disease show symmetrical lesions in the paraventricular regions of the thalamus and hypothalamus, mammillary bodies, periaqueductal region of the midbrain, floor of the fourth ventricle (particularly in the regions of the dorsal motor nuclei of the vagus and vestibular nuclei), and superior cerebellar vermis. Lesions are consistently found in the mammillary bodies and less consistently in other areas.
תיאור של וורניקה-קורסקוף. מה מהבאים ישתפר ראשון לאחר מתן הטיפול:
1. אופתלמופלגיה
2. אטקסיה
3. בלבול
4. הפרעת זכרון
אופתלמופלגיה ישתפר ראשון
בחורה עם הקאות מרובות. בבדיקה אטקסיה, הפרעה בתנועות עיניים ובלבול. מה הפתולוגיה בהדמייה?
1. T2 mamillary bodies
2. T2 pons
3. T2 meningeal enhancement
T2 mammillary bodies
The changes are most apparent on the fluid-attenuated inversion recovery (FLAIR), T2, and diffusion-weighted sequences (if there is hemorrhage), but they may also Enhance. It is not clear to what extent gradient-echo MRI images can be expected to consistently reveal the small hemorrhagic lesions of the diencephalon and periventricular areas. imaging is particularly useful in patients in whom stupor or coma has supervened or in whom ocular and ataxic signs are otherwise inevident, but in milder cases a normal MRI does not preclude the diagnosis. The typical MRI changes are observed in only 58 percent of cases according to Weidauer and colleagues. In the chronic state, the mammillary bodies
may be shrunken if measured by volumetric techniques
בן 70, מובא על ידי משפחתו עקב ירידה קוגניטיבית בשבועיים האחרונים. בבדיקתו הפרעה בזיכרון לטווח קצר בלבד, קשב והתמצאות שמורים. אין הפרעה ויזוספציאלית. מה האבחנה?
א. TGA
ב. קורסקוף
ג. אלצהיימר
ד. Multi-infarct dementia
קורסאקוף
The Korsakoff amnesic state (Korsakoff psychosis) retentive memory is impaired out of proportion to all other cognitive functions in an otherwise alert and responsive patient. most often associated with the thiamine deficiency of alcoholism and malnutrition, but it may be a symptom in structural lesions of the medial thalami or the hippocampal portions of the temporal lobes, such as infarction in the territory of branches of the posterior cerebral arteries, hippocampal damage after cardiac arrest, third ventricular tumors, and herpes simplex encephalitis. An almost equivalent type of memory disturbance may also follow acute lesions of the basal septal nuclei of the frontal lobe. Transient impairments of retentive memory of the Korsakoff type may be the salient manifestations of temporal lobe epilepsy, concussive head injury, and a transient global amnesia. The anatomic basis of the Korsakoff amnesic syndrome is described in Chap. 20.
In the nutritionally deficient patient, Korsakoff amnesia is usually associated with and immediately follows the occurrence of Wernicke disease
term Wernicke disease or Wernicke encephalopathy is applied to a symptom complex of ophthalmoparesis, nystagmus, ataxia, and an acute apathetic–confusional state. If an enduring defect in learning and memory results, as it often does, the symptom complex is designated as the Wernicke-Korsakoff syndrome.
קורסאקוף נראה כמו
TGA
ארוך!