Definition
Triggered by a chronic vitamin B12 deficiency, funicular myelosis results in the regression of certain spinal cord areas.
Symptoms
Funicular myelosis is characterized by a breakdown of the myelin sheaths surrounding the nerves (so-called demyelination). If this sheathing of the nerve cells is missing, malfunctions and short circuits occur in the transmission of nerve impulses and stimuli. In funicular myelosis, the posterior strands and the lateral pyramidal strands of the spinal cord are particularly affected.
Here, information from the sensory organs is passed on to the brain. A dysfunction such as funicular myelosis leads to insecure gait and the resulting dizziness, as the body can no longer orient itself correctly in space (impaired depth sensitivity). In addition, patients suffer from sensory dysfunctions and pain, especially in the legs.
In addition, there is a rapid fatigue when walking, tongue burning and impotence, as well as urinary retention. If the optic nerve or the nerve path of vision is also affected, visual disturbances may occur. In most cases, funicular myelosis occurs in patients around the age of 45 years.
Muscle twitching is not a typical or specific symptom of funicular myelosis, but may occur. One reason for this is the increased reflexes. Even the slightest touch or movement, which would have no further consequences in a healthy person, can trigger reflexes and thus muscle twitches.
Spastic paralysis can also develop, which may initially manifest itself through muscle twitches. On the other hand, the muscle twitches can occur as a sign of loss of the sense of position (proprioception). If the sense of position is disturbed, one is no longer able to determine the position and posture (position) of e.g. the arm with closed eyes. The body’s own sense of self is missing. Balancing movements in the form of muscle twitches can occur.
Causes
The cause of funicular myelosis is the chronic deficiency of vitamin B12. In order to absorb the vitamin in the intestines, the body produces the so-called intrinsic factor in the stomach, which means that in stomach diseases there may be a malfunction of vitamin B12 absorption when the production of the intrinsic factor is disturbed. Another possible cause of a defective vitamin B12 deficiency is pernicious anemia.
Severe damage to the stomach lining can occur in cases of chronic gastritis (chronic atrophic gastritis), a malignant stomach tumor (gastric carcinoma; stomach cancer) or alcoholism, among others. If the stomach has been surgically removed, for example because of a gastric tumor, the stomach lining and thus the intrinsic factor formed there is completely absent. Similarly, fish tapeworm infestation can lead to such a high consumption of vitamin B12 by the parasite that the patient’s body no longer has sufficient vitamin B12 available for its own metabolism.
There is also an increased need for vitamin B12 during pregnancy and in various cancer diseases, such as leukemia or myeloma. If there is a pathological bacterial colonization in the intestine of the patient, a Vitamin B12 deficiency can also result from this. A one-sided nutrition, as well as hunger can also lead to an undersupply of vitamin B12.
The absorption of vitamin B12 can be negatively influenced by several intestinal diseases. These include, for example, Crohn’s disease and celiac disease (in adults), as well as celiac disease (in children) and the chronic functional impairment of the pancreas (chronic pancreatic insufficiency after inflammation or similar disease). If a part of the patient’s intestine has been removed, this can also lead to a reduced absorption of vitamin B12.
Some drugs, for example antiepileptic drugs and cytostatics, can have a negative effect on vitamin B12 metabolism. In addition, there are drugs that inhibit the absorption of vitamin B12 in the ileum. Proton pump inhibitors and the anti-diabetic drug metformin are particularly worth mentioning in this context, as these are very frequently taken drugs that are often prescribed regularly even in combination.
This may result in a serious vitamin B12 deficiency with symptoms of funicular myelosis, which can be misdiagnosed as diabetic polyneuropathy, especially in affected diabetics. The actual cause of the polyneuropathy is therefore not treated, although the symptoms could be remedied by simple administration of vitamin B12 (intravenously or orally).In the liver of humans a depot is available at Vitamin B12, therefore lack symptoms show up only after approximately 3 years impairment of the Vitamin B12 admission. The vitally necessary Vitamin can be manufactured only by bacteria and is naturally present in animal products such as meat, poultry, fish, mussels, sea fruits and little also in milk.
In yeast or plant products it does not occur in general, which means that especially vegans or vegetarians have to take vitamin B12 as a dietary supplement. Even people who are older than 50 years old should take additional vitamin B12 in order to fully cover their needs. In the case of chronic alcohol abuse, a vitamin B12 deficiency is more likely to occur, which in turn can lead to funicular myelosis.
Vitamin B12 deficiency is caused on the one hand by a chronic inflammation of the stomach lining, which occurs very frequently in alcoholics. The stomach lining can no longer produce the substance (intrinsic factor) necessary for the absorption of the vitamin, which is why vitamin B12 can no longer be absorbed. On the other hand, chronic alcoholics often no longer eat a balanced, healthy diet and do not get enough vitamin-B12 from outside. Vitamin B12 deficiency can also be caused by alcoholism. These articles may also be of interest to you:
- Consequences of alcohol
- Effect of alcohol on the various organs of the body
- Alcohol addiction
