Lathyrism is a syndrome that occurs as a result of slow poisoning; it is caused by excessive consumption of certain dodder peas over a long period of time. As neuro-lathyrism, the disease damages the nervous system and causes chronic spastic paralysis.
What is lathyrism?
Lathyrism is a syndrome caused by gradual poisoning. The cause of the poisoning is the excessive consumption of certain peas over a long period of time. Lathyrism appears mainly in the form of neuro-lathyrism. In this case, the poisoning affects the motor nervous system and leads to a variety of motor and sensory symptoms. Lathyrism is particularly prevalent in geographic areas characterized by severe aridity of the climate. It can assume the proportions of an epidemic when, due to unfavorable climatic conditions, large segments of the population depend on the consumption of chickling peas and foods made from them (especially flour). Because chickling peas have a high resistance to drought, they are sometimes the only remaining staple food under unfavorable agricultural conditions. While lathyrism tends to be a thing of the past in Europe, epidemic proportions of lathyrism are known, particularly from Ethiopia, China, India and Bangladesh. Not only humans contract lathyrism; animals such as horses can also be affected.
Causes
Lathyrism is also known as “chickpea poisoning.” However, the syndrome is not caused by excessive consumption of chickpeas, but by that of seed chickpeas. Seeded chickpeas, however, look very similar to the seeds of chickpeas. If a person’s diet consists of at least 40 percent peas and chickpea species for at least six months, they are at high risk of developing lathyrism. However, even eating smaller amounts can cause symptoms of poisoning. Chickling peas (Lathyrus) belong to the legume family and occur in numerous species. Some species contain so-called lathyrogenic amino acids, especially in the seeds. These are toxic and trigger the disease in humans. The propionitrile derivatives of the plant have a neurotoxic effect: they damage the motor nerve fibers that transmit the signals for contraction or relaxation from the nervous system to the muscles. By interfering with signal transmission, propionitrile derivatives impair the functioning of the musculoskeletal system: the nerve fibers do not transmit the commands from the central nervous system, or transmit them incompletely, or false signals are generated, leading to involuntary contractions of the muscles. These involuntary movements are thereby beyond the control of the affected person.
Symptoms, complaints, and signs
Lathyrus poisoning results in characteristic symptoms such as pain, limb twitching, and spasms of the extremities. Weak or stiff, immobile legs are also among the symptoms of lathyrism. Another feature of the disease is so-called paresthesias. These are spurious sensations such as tingling, itching, and the perception of cold or warmth that are not based on an actual stimulus. In addition, the disturbed neuronal transmission can lead to tremor of the arms in rarer cases. In a tremor, the affected person suffers from a rhythmic twitching, in this case in the muscles of the arms. In some cases, sufferers can temporarily suppress the tremor, but not completely or permanently. Tremor is not unique to lathyrism; it is a potential sign of disease for numerous conditions. Tremor due to lathyrism is a so-called toxic tremor caused by intoxication. In lathyrism, sensory disturbances (hypesthesia) may also manifest. These are disturbances in the perception of touch and pressure on the skin. In addition, the sensation of temperature, pain and position may be impaired. Acute gastrointestinal problems and bladder dysfunction may also occur as part of lathyrism.
Diagnosis and course of the disease
For a correct diagnosis, a good medical history plays a crucial role above all. Without treatment of lathyrism, the symptoms described above may increase.In the later course of the disease, paraspasticity may occur: A spastic paralysis of both legs. Another potential consequence of lathyrism is blindness in the form of retrobulbar neuritis. This is an inflammation of the optic nerve behind the eyeball that causes blindness.
Complications
In most cases, lathyrism is diagnosed at a very late stage. This is because the symptoms only become noticeable over time and are not particularly characteristic of this disease. In most cases, those affected suffer from cramps and involuntary muscle twitching. Sometimes the legs can only be moved with difficulty and appear very stiff. The quality of life of the affected person is significantly reduced and limited by lathyrism. Likewise, there is itching and tingling in various regions of the body. The patient’s perception is also negatively affected by this disease. It is not uncommon for complaints to occur in the stomach and intestines and for those affected to suffer from restrictions in the bladder. In the worst case, without treatment of lathyrism, the affected person will die. Direct treatment of the symptoms is often not possible. As a rule, the sufferer of lathyrism must abstain from the sacred ingredient and stop eating the beans. In most cases, this can limit the symptoms. Life expectancy is usually only reduced if consumption is not restricted and the sufferer continues to consume the beans or seeds.
When should you see a doctor?
A number of characteristic symptoms occur with lathyrism. If limb twitching, cramps or unusual pain are noticed, a doctor should be consulted. The same applies to weak and immobile or stiff legs. If paresthesias are added to these symptoms, there may be a serious underlying condition that needs to be investigated. People who notice repeated twitching or notice that the above symptoms are increasing are best to talk to their family doctor immediately. At the latest, if disturbances of the bladder function or acute gastrointestinal complaints are added, the lathyrism must be taken to the doctor. The physician can clarify the cause and initiate appropriate therapy, which usually causes the symptoms to subside quickly. Further visits to the doctor are necessary if the treatment has no effect or if symptoms reappear after some time. The right contact person is the general practitioner or an internist. Allergy sufferers should talk to the allergist in charge and inform him about the unusual symptoms. Children always require a pediatric examination if they have symptoms of lathyrism.
Treatment and therapy
When small amounts of Lathyrus seeds are consumed, the administration of charcoal may be considered as the first treatment measure. The Information Center against Poisoning in NRW recommends this measure for a dose of 20 to 50 seeds. If less than 20 seeds are consumed or the flowers of the vetchling are eaten, the Poison Control Center recommends drinking plenty of fluids, provided no symptoms are present. If symptoms occur, medical advice is needed. A specific treatment, especially for advanced lathyrism, does not exist. However, in principle, improving the diet and taking high doses of vitamin B are among the measures that various sources consider useful. However, the exact therapy must be determined individually by physicians; the choice of treatment method depends primarily on the stage of the disease and the therapeutic measures available locally.
Outlook and prognosis
The timing of treatment initiation is an essential criterion for a favorable prognosis. If therapy is foregone altogether, symptoms will worsen. Spastic paralysis of the legs is then just as possible as blindness. Non-treatment is thus associated with the worst prospects. Long-term negative consequences also result if people have made chickpeas a main food component over a long period of time. In industrialized countries, lathyrism almost no longer occurs. The disease is particularly prevalent in economically weaker regions in China and India. Historically, during periods of famine, the population resorted to eating chickpeas because no other food was available.For example, it is documented from the Napoleonic wars. Animals can also fall ill from chickpea poisoning. If small amounts are consumed once, even an abundant intake of water will alleviate the symptoms. Prognosis in the early stages is generally good. However, pre-existing conditions and advanced age can cause complications. Poisoning is not as well tolerated by such organisms. If dodder peas become a major food component over a long period of time, irreparable long-term damage must be expected.
Prevention
To prevent lathyrism, a balanced diet and avoidance of (regular) consumption of the chickpea is of great importance. However, lathyrism occurs mainly in times of hardship and in poorer countries, where the affected populations do not have the choice to abstain from eating chickpea as a food. In the long term, green genetic engineering aims to provide a remedy for this problem: The toxic substances in the seeds of the Lathyrus species could be eliminated with the help of genetic engineering. However, the breakthrough success of this measure has yet to be seen.
Aftercare
In most cases, the measures of an aftercare for a lathyrism are severely limited, so that affected persons with this disease are primarily dependent on a quick and, above all, also on an early diagnosis of the disease. As a rule, the disease cannot be cured on its own, so that treatment by a doctor is always necessary. The earlier a doctor is consulted, the better the further course of the disease usually is. Direct treatment is not always necessary for this disease. In many cases, the poisoning can also be alleviated relatively well by taking charcoal, although the affected person should pay attention here to a correct dosage and also to a regular intake of the tablets. Likewise, the intake of vitamin B through food can have a positive effect on the further course of lathyrism and alleviate the symptoms. In this case, a doctor can prepare a diet plan, which can generally have a positive effect on the further course of the disease. As a rule, lathyrism does not reduce the life expectancy of the affected person.
What you can do yourself
If lathyrism poisoning is suspected, a doctor must be consulted in any case. Accompanying the medical therapy, some household and natural remedies can be resorted to in order to alleviate the symptoms and discomfort. First, however, the affected person should take it easy and pay attention to a balanced and healthy diet. In the first days after the poisoning, the diet should consist of diuretic and laxative foods so that the toxin can be flushed out as quickly as possible. Foods high in vitamin B should also be included in the diet. Thus, dairy products, liver and cereal products help the body to remain efficient despite poisoning and to overcome the disease without consequences. Furthermore, sufficient liquid should be taken in, preferably water or herbal teas. Diuretic preparations from the drugstore are also suitable. For gastrointestinal complaints or headaches, preparations from naturopathy, such as valerian, arnica or lemon balm, as well as preparations with calendula ointment, are helpful. The exact therapy must be determined together with a doctor, who will include the constitution of the patient and the stage in which the lathyrism is.
