What Is Beriberi?
Beriberi is a moderate to severe thiamine nutrient deficiency mainly caused by dietary lack of thiamine or vitamin B1. It is, in fact, capable of inflicting lasting damage targeting the nervous system and heart. The word beriberi is derived from a Sinhalese word meaning “extreme weakness or fatigue” as the severe deficiency in this vitamin B1 manifested as defective enzymatic and metabolic pathways in the energy cycle of the body leading to life-threatening symptoms in patients with a severe deficit.
What Are the Functions of Thiamine?
Thiamine is a nutrient-rich source that people obtain dietarily and has multiple roles in many enzymatic bodily functions, including breaking down of carbohydrates, muscular contractions, stimulation of conduction in nerve cell pathways, reduction of glucose, and creation of acids that aid in digestion.
Thiamine (vitamin B1) was the first B vitamin to have been identified, but the detrimental effects of thiamine deficiency have been linked to several causatives in developing countries. Thiamine is also a cofactor for several enzymes involved in these constant metabolic cycles to produce energy. The thiamine-dependent enzymes are fundamentally not only important for the biosynthesis of neurotransmitters but also for producing reducing substances that are used up by our immune system in oxidant stress defense. Thiamine is also pivotal to the synthesis of pentose for the production of nucleic acid precursors.
What Causes Thiamine Deficiency?
Beriberi is thus principally a deficiency of this vitamin B1 or thiamin. It is quite common to experience thiamine deficiency in pregnancy and lactation that raise the threshold for an individual's thiamin requirement. Even in breastfed infants who can potentially acquire the symptoms of this disease clinically, this remains a crucial element dietarily as the milk derived from a malnourished mother may be deficient in thiamin if the pregnancy or lactating patient is suffering from thiamine deficiency during this phase.
Thiamine plays a central role in cerebral metabolism that has major manifestations in the cerebral linked thiamine deficiencies (TD), namely cardiovascular disease in the case of wet beriberi and nervous system linked diseases in the case of dry beriberi and Wernicke–Korsakoff syndrome.
Before the discovery of thiamine, the major health problem was found in people hailing from East Asian countries where polished rice (thiamine is mainly present in the husk of rice) is the staple food, given the fact that thiamine is mainly present only in the husk of the rice. These causes of thiamine deficiency include the reliance on foods in which the vitamin has been inactivated by processing in the case of polished rice, more seen in developing countries where it is a staple diet.
Also, other causes like overcooking or eating foods that contain thiaminase-producing bacteria, as seen in people who in some raw fish, etc., may also be some reasons for dietary deficiency of B1.
Research suggests that thiamine deficiency has been reported to cause severe neuropathies or specific conditions like postural orthostatic tachycardia syndrome. Research also indicates that it is possible to trace beriberi as a genetic disorder that can be transmitted from the mother to their infants while breastfeeding if the mother’s body is thiamine deficient.
What Are the Clinical Features of Beriberi?
Important symptoms of beriberi not only include loss of normal appetite and disturbances in the gastrointestinal tract but also the affected individuals feeling extreme weakness. Due to weight loss, the patient may become extremely thin and develop cardiac issues or edema in certain regions.
In cases of severe deficiency, mental depression, loss of memory, and anxiety associated with the onset of neuropathies may be very common.
Beriberi is also a polyneuritic syndrome affecting the lower limbs. Symptoms of dry beriberi include weakness and pain in the limbic regions, weight loss, and in severe cases, partial paralysis.
Beriberi, however, remains the main classical manifestation of chronic dietary deficiency related to vitamin B1.
1. Symptoms of Wet Beriberi:
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Increased heart rate or tachycardia.
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Swelling or edema of the lower legs.
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Muscle weakness, insomnia, or inability to sleep.
2. Symptoms of Dry Beriberi:
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Pain strange tingling sensations.
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Confusion.
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Difficulty in walking properly.
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Difficulty in eye movements.
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Difficulties in speech or ability to speak.
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Partial or complete loss of sensation in hands and feet in severe cases.
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Loss of muscle functioning or, lastly, paralysis of the lower limbs in severe deficiency.
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Wernicke Encephalopathy - This is a complicated disorder that can definitively cause damage to the regions of the thalamus and hypothalamus of the brain with symptoms such as confusion, loss of memory coordination, loss of muscular activity, and muscle tone issues with vision.
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Korsakoff Syndrome - This condition is also linked to thiamine deficiency, causing damage in the memory-forming units of the brain. This leads to symptoms such as memory loss and hallucinations problems in forming new memories for the patient.
How to Diagnose Thiamine Deficiency?
Physicians may rely on both blood as well as urine tests to help measure the levels of thiamine in a person’s bloodstream to diagnose beriberi. The reference range ideally for thiamine in normal individuals is 2.5 - 7.5 micro g/dL in blood.
In wet beriberi, the cardiovascular symptom is more prominent because of cardiac insufficiency and enlargement, with a tendency to have rheumatoid inflammation. Physicians may recommend assessing the TK (thymidine kinase) activity in red blood cells. A comparatively or severely low TK activity of red cells is a reliable diagnostic indicator of mild, moderate, or severe thiamine deficiency.
Physical examination to check for vital signs and other neurological damages or cardiac issues should be crosschecked by referral to a cardiologist or neurologist. The common signs of neurological damage to look out for are mainly the ability to walk properly or stay balanced during walking or in certain postures. This can show if there are any issues with the patients' lack of coordination or weak reflexes due to disturbances in the reflex arc pathway. Tachycardia and edema in affected areas are also to be checked by the physician apart from this basic diagnostic criterion for treating beriberi.
How to Prevent and Manage Beriberi?
To prevent beriberi, it is essential in maintaining a healthy and balanced diet is important. Foods that are rich in thiamine such as milk products, green leafy vegetables, fortified cereals, proteinaceous eggs, fish, legumes, meats, nuts, seeds, whole grains, and certain vegetables like asparagus, beet greens, brussels sprouts, squash, tomatoes, etc., can definitely aid in better prognosis by dietary consumption for thiamine deficient individuals.
Beriberi patients who have a history of either alcohol abuse or suffer from chronic alcoholism as a habit should undergo counseling to get rid of the habit completely or limit alcohol consumption to reduce further risk of aggravating cardiac or neurologic complications due to vitamin B1 deficiency.
This disorder can be mainly explicitly targeted by the physician in an attempt to replace the thiamine level in the blood cells by hence increasing the daily dietary intake of vitamins. Patients may also be treated with Thiamine supplements that can be given orally or in injectable form, depending on the extent of weakness.
Along with the diet and medications, patients are also advised for regular follow-up and blood tests to monitor if the body is functioning enough to absorb the vitamin correctly.
Conclusion:
To conclude, the dietary supplementation with thiamine and identification of clinical symptoms of this deficiency helps in managing this condition without aggravating neurologic or cardiac complications. Also, during pregnancy and lactation, thiamine deficiency should be avoided to prevent potential transmission to the infant.