The patients with beriberi do not report any signs or symptoms of thiamine deficiency. Signs and symptoms at the early stage are often nonspecific, such as fatigue, thigh failure of high cardiac-output can direct the diagnosis to thiamine deficiency.

Some of the neurological symptoms of beriberi are: poor memory, sleep disturbances, Korsakoff syndrome, irritability, muscle cramps, muscle atrophy, and foot drop. Beriberi also manifests with some cardiovascular symptoms such as tachycardia, heart failure, chest pain, hypotension and shock. The gastroenterologic symptoms of beriberi are anorexia, constipation, dysphagia, and abdominal discomfort [6] [7].

• Malnutrition

  "Shoshin beriberi", which is a fulminant form of cardiovascular beriberi accompanied by hemodynamic deterioration with high cardiac output and decreased systemic blood pressure, caused by thiamine deficiency due to alcoholic abuse or malnutrition, is [ncbi.nlm.nih.gov]

  Beriberi was a disease of malnutrition caused by the consumption of overmilled rice. [dictionary.cambridge.org]

• Congestive Heart Failure

  This was defined as the presence of signs of congestive heart failure or shock in the absence of fever or other signs of sepsis, hypovolaemia or cardiac abnormalities, with rapid clinical improvement following parenteral thiamine. [ncbi.nlm.nih.gov]

  Complications may include: Coma Congestive heart failure Death Psychosis Beriberi is extremely rare in the United States. [nlm.nih.gov]

  Although, untreated Beriberi can eventually lead to death Commencing thiamine supplementation can cause an improvement in the symptoms If congestive heart failure occurs, the prognosis is poor. [dovemed.com]

  Congestive heart failure may need to be excluded as may other vitamin deficiencies (vitamin B12, niacin) if neurological symptoms are present. [patient.info]

• Fatigue

  The most common symptoms of chronic beriberi due to thiamine deficiency include dyspnoea, fatigue, leg oedema, lower extremity weakness and numbness. [ncbi.nlm.nih.gov]

  Symptoms are fatigue, diarrhea, appetite and weight loss, disturbed nerve function causing paralysis and wasting of limbs, edema, and heart failure. [medical-dictionary.thefreedictionary.com]

  In the childhood and adult versions of the disease there is a preliminary condition of fatigue, loss of appetite, and a numb tingling feeling in the legs. This condition can then lead to either wet or dry beriberi. [science.jrank.org]

  Beriberi is the result of a prolonged thiamin deficiency with symptoms including fatigue, poor reflexes, irritability, memory loss, and sleep disturbances. [web.archive.org]

• Burning Feet

  Deficiency diseases: Pellagra, sub-acute combined degeneration, burning feet syndrome and pyridoxine deficiency. ii. Metabolic diseases: Diabetes Mellitus, Uremia, Porphyria etc. iii. [biologydiscussion.com]

  feet, and later symptoms consist of painful parasthesias in the distal upper limbs as well, weakness and atrophy of the feet and hands, and distal atrophic skin and hair loss; the "wet" form is characterized by edema resulting from a high output form [medical-dictionary.thefreedictionary.com]

  feet), - targeted compensation of detected deficiencies, - life-long supplementation and controlled adjustment, - periodic follow-up examinations to close inspection intervals. [karger.com]

• Tachypnea

  Respiratory system examination revealed tachypnea and on auscultation there were bilateral basal fine crepitations, electrocardiogram showed T wave inversions. Abdominal examination revealed tender hepatomegaly. [jdrntruhs.org]

  Recent surveys using whole blood thiamine diphosphate (TDP) revealed that thiamine deficiency was associated with cardiac dysfunction and tachypnea in Cambodian infants [ 32, 34 ]. [ncbi.nlm.nih.gov]

• Loss of Appetite

  General symptoms include loss of appetite and overall lassitude, digestive irregularities, and a feeling of numbness and weakness in the limbs and extremities. (The term beriberi is derived from the Sinhalese word meaning “extreme weakness.”) [humantermuem.es]

  In the childhood and adult versions of the disease there is a preliminary condition of fatigue, loss of appetite, and a numb tingling feeling in the legs. This condition can then lead to either wet or dry beriberi. [science.jrank.org]

  Beriberi is a disease caused by a lack of Vitamin B1 (thiamin).The thiamin-deficiency disorder is characterized by muscle weakness, loss of appetite, nerve degeneration and sometimes oedema. [infonet-biovision.org]

• Acute Abdomen

  In this article, we report the case of a 7-month-old child with thiamine deficiency presented with neurological symptoms and simulation of acute abdomen. [ncbi.nlm.nih.gov]

• Heart Failure

  Shoshin beriberi, a fulminant form of heart failure due to thiamine deficiency has a different presentation to the classical form of beriberi heart failure. [ncbi.nlm.nih.gov]

  Both patients responded dramatically to thiamine, and this emphasizes the importance of considering thiamine deficiency as a cause of heart failure even when the cardiac output is low. [doi.org]

  Congestive heart failure may need to be excluded as may other vitamin deficiencies (vitamin B12, niacin) if neurological symptoms are present. [patient.info]

• Tachycardia

  Parts of the heart, thus, undergo injury and the patient starts showing physical symptoms of tachycardia, edema and myocardial injury. [symptoma.com]

  Beriberi, also caused by thiamine deficiency, accounted for his tachycardia, polyneuropathy, areflexia, hypothermia and biochemical abnormalities. [ncbi.nlm.nih.gov]

  The patient developed progressive ascending weakness, limited extraocular movement, confusion, edema, tachycardia and hypotension. He was intubated and mechanically ventilated. [jcmr-online.biomedcentral.com]

  Later, patients experience weakness, peripheral neuropathy, headache, and tachycardia. [fpnotebook.com]

• Hypotension

  "Shoshin beriberi" cardiac failure has a different presentation, with vasoconstriction, hypotension and severe metabolic acidosis. A three-month breast-fed infant developed these features (biochemical tests confirmed the diagnosis). [ncbi.nlm.nih.gov]

  He became hypotensive and laboratory evaluation revealed an elevated Troponin-I level of 20.95 ng/mL (Reference value 0.11 ng/mL). [jcmr-online.biomedcentral.com]

  After 5 days of daily 100 mg IV thiamine and supportive care, the hypotension resolved and the patient was extubated and was released from the hospital 3 weeks later. Our case shows via CMR profound myocardial edema associated with wet beriberi. [vumc.org]

  Beriberi also manifests with some cardiovascular symptoms such as tachycardia, heart failure, chest pain, hypotension and shock. The gastroenterologic symptoms of beriberi are anorexia, constipation, dysphagia, and abdominal discomfort. [symptoma.com]

• Jugular Venous Distention

  He had slight jugular venous distention, edema of the face and upper and lower extremities, ascites, and loud heart sounds with an S3 gallop. [ncbi.nlm.nih.gov]

• Orthostatic Hypotension

  Also or just may be present: -tachycardia, hypotension, chest pain, cardiomegaly, dyspnea, rapid pulse and/or orthostatic hypotension. [enfermedad-de-wernicke.weebly.com]

• Muscle Weakness

  Muscle weakness in the first patient progressed even after admission to the hospital, and urinary retention, Wernicke's encephalopathy, lactic acidosis, paralytic ileus, and heart failure appeared subsequently. [ncbi.nlm.nih.gov]

  leg cramps, muscle weakness), limb swelling, elevated pulse, and heart failure. Wernicke-Korsakoff syndrome is a related condition (with symptoms such as a jerky gait, disorientation, and impaired short-term memory) that occurs among alcoholics. [diet.com]

• Numbness of the Feet

  The toes feel numb and the feet have a burning sensation; the leg muscles become sore and the calf muscles cramp. The individual walks unsteadily and has difficulty getting up from a squatting position. [encyclopedia.com]

  Severe thiamin deficiency leads to a disease called beriberi with the added symptoms of tingling and numbness in the feet and hands, loss of muscle, and poor reflexes. Beriberi is not common in the United States and other developed countries. [web.archive.org]

• Muscular Atrophy

  Classically it is characterized by multiple neuritis, muscular atrophy, weakness, cardiovascular changes, and progressive edema. beriberi the name given to thiamin deficiency in humans. See thiamin nutritional deficiency. [medical-dictionary.thefreedictionary.com]

• Arthralgia

  Amerindian communities of Uiramutã, state of Roraima, Brazil, June 2008 Signs and symptoms N Percent Lower extremity edema 77 85 Lower extremity parasthesias 76 83 Leg pain 71 78 Weakness 71 78 Difficulty walking 69 76 Fatigue 67 74 Difficulty running 60 66 Arthralgia [ncbi.nlm.nih.gov]

• Facial Edema

  The first patient had generalized edema on inspection (pedal, sacral as well as facial edema), and evidence of pericardial effusion with increased left and right ventricular thickness. The lungs were edematous with areas of consolidation. [doi.org]

• Psychiatric Manifestation

  Beriberi is one of several thiamine-deficiency related conditions which may occur concurrently, including Wernicke's encephalopathy (mainly affecting the central nervous system), Korsakoff's syndrome (amnesia with additional psychiatric manifestations [icd.codes]

  Beriberi is one of several thiamine-deficiency related conditions, which may occur concurrently, including Wernicke's encephalopathy (mainly affecting the central nervous system), Korsakoff's syndrome (amnesia with additional psychiatric manifestations [ipfs.io]

• Nystagmus

  Proximal myopathy, lower limb fasciculations and areflexia, restricted bilateral eye abduction and nystagmus were observed. Blood investigations demonstrated compensated lactic acidosis, acute kidney injury and leucocytosis. [ncbi.nlm.nih.gov]

  Classically, Wernicke encephalopathy is characterized by confusion (encephalopathy), ataxia, and nystagmus. Korsakoff syndrome is a more severe finding that includes confabulations. [pixorize.com]

  In the pseudomeningitic variety there there are symptoms of nystagmus, vomiting and convulsions but normal cerebrospinal fluid (CSF). [patient.info]

  Signs include: nystagmus (flickering of the eye), muscle twitching; a bulging fontanelle; and convulsions and unconsciousness. [web.archive.org]

• Peripheral Neuropathy

  An adult with Crohn's disease on home total parenteral nutrition (TPN) for 8 months presented with peripheral neuropathy and ataxia. The patient was found to be deficient of thiamine. [ncbi.nlm.nih.gov]

  The manifestations of the disease are peripheral neuropathy (impairment of the sensory, motor or reflex functions of the extremities), or degeneration of the myelin in muscle sheaths. [symptoma.com]

• Paresthesia

  Cases had lower extremity edema (85%), upper extremity paresthesias (84%), and lower extremity weakness and pain (78%). [ncbi.nlm.nih.gov]

• Amnesia

  Beriberi is one of several thiamine-deficiency related conditions which may occur concurrently, including Wernicke's encephalopathy (mainly affecting the central nervous system), Korsakoff's syndrome (amnesia with additional psychiatric manifestations [icd.codes]

  […] neurological syndromes are recognized: dry beri-beri (a patchy axonal polyneuropathy), Wernicke encephalopathy (characterized by the triad of confusion, ophthalmoplegia, and ataxia), and Korsakoff’s psychosis (manifesting as retrograde and anterograde amnesia [n.neurology.org]

  Retrograde amnesia, inability to form new memories, confabulation and hallucinations are the most common signs and symptoms. Korsakoff’s psychosis isn’t curable; sufferers are permanently handicapped and often require ongoing supervision. [ems1.com]

  The essential features are anterograde and retrograde amnesia, often with disorientation and confabulation. The last usually makes the patient delightful but any check of the authenticity of stories will reveal them as confabulation. [patient.info]

• Apathy

  Hypermetabolic states also predispose to deficiency and this includes fever, pregnancy, postoperative state, total parenteral nutrition and renal dialysis. [ 11 ] A loop diuretic can also increase the risk. [ 12 ] Presentation History Early features Fatigue and apathy [patient.info]

  It is accompanied by a degree of apathy – lack of interest in life or other activities that were previously enjoyable. Often patients are diagnosed with depression at this point. [healthhype.com]

  It is characterised by weakness of eye muscles, so that the patient cannot look upwards or sideways and a state of disorientation and apathy. [biologydiscussion.com]

  These brain abnormalities are called the Wernicke-Korsakoff syndrome, which has two parts: Wernicke encephalopathy causes confusion, apathy, difficulty walking, and eye problems, including involuntary eye movements (nystagmus) and partial paralysis of [merckmanuals.com]

Replacing of thiamine is the first step to ascertain the diagnosis of the disease. If the patient responds to the treatment, it would be safe to measure the thiamine deficiency as the cause of the trouble. Since thiamine is non-toxic at higher levels, this method of managing the condition offers little risk.

Measuring blood thiamine pyruvate, glyoxylate levels and alpha-ketoglutarate levels, urinary excretion of thiamine and its metabolites provides the correct diagnosis of the condition.

Thiamine loading test has been considered as the best indicator of thiamine deficiency. If there is an increase of more than 15% of the enzyme activity is seen, it is indicative of a deficiency of the vitamin. This test, however, is both expensive and time-consuming.

Urinary methylglyoxal levels: Measuring methylglyoxal levels and thyroid-stimulating hormone (TSH) also helps to rule out thyrotoxicosis-induced heart failure.

Troponin I: Higher levels of troponin I is seen in patients with heart failure induced by thiamine deficiency.

Metabolic acidosis is also caused by thiamine deficiency because of the increased lactic acid production. In gastrointestinal beriberi, patients report abdominal pain caused due to lactic acidosis [8] [9][10].

• Thiamine Decreased

  Daily needs for thiamine decrease when fat forms a large part of the diet and increase when the diet is high in carbohydrates. Pregnancy, lactation, an overactive thyroid and fever increase the requirement for thiamine. [health24.com]

  Decreased uptake of thiamine from the GI tract: Active transport of thiamine into enterocytes is disturbed during acute alcohol exposure. Liver thiamine stores are reduced due to hepatic steatosis or fibrosis. [en.wikipedia.org]

The goal of the treatment of beriberi is to substitute the deficiency of thiamine, reduce the morbidity associated with such deficiency and prevent complications. If the correct diagnosis is ascertained, there must be prompt administration of parenteral thiamine. Thiamine substitution therapy must be continued until all the symptoms associated with beriberi are gone [11].

Beriberi, if not cured on time, can be fatal. In this disease, the patient is robbed of the energy even for the daily activities making them lethargic. Beriberi is treatable even in the severe cases. Thus, the prognosis of the patient with beriberi is good. In case of wet beriberi, the improvement is observed within 12 hours.

Development of beriberi is caused by the deficiency of thiamine. There are several mechanisms by which this can occur, such as lack of thiamine intake, increased consumption of thiamine, and decreased absorption.

Lack of thiamine intake: A diet with high levels of thiaminases (milled rice, raw freshwater fish, ferns), anti-thiamine factor (tea, coffee, or betel nuts), or high levels of sulfite causes a lack of thiamine. There are some diet-related factors that can cause a reduction in the thiamine intake are alcoholic state, starvation state and gastric bypass surgery or parental nutrition devoid of adequate thiamine levels.

Increase in the consumption of thiamine: The increase in the metabolism of thiamine can result from having a diet rich in carbohydrate or saturated fat, hypothyroidism, pregnancy, lactation, fever with severe infections. Increased depletion of thiamine occurs in patients with diarrhea, or one who are undergoing diuretic therapies, hemodialysis, or peritoneal dialysis. Thiamine loss is often associated with the increase in the rate of urine flow.

Decrease in the absorption of thiamine: Reduction in the absorption of thiamine is observed in patients with chronic intestinal disease, malnutrition, gastric bypass surgery, folate deficiency, and alcoholism. Folate deficiency causes indirect thiamine deficiency as thiamine of the body is not activated.

Infantile beriberi: Infantile beriberi occurs in the infants who are 2-4 months of age and are exclusively fed with mother’s milk, whose mother is thiamine deficient.

Patients with chronic alcoholism must be administered parenteral thiamine as alcohol is a direct neurotoxin and causes low and impaired thiamine intake and storage. It also leads to the accelerated destruction of the thiamine diphosphate. When the person is dieting, he often neglects the correct intake of micronutrients, and hence leads to several vitamin deficiency diseases [3] [4].

The population of developing countries is at a higher risk of vitamin deficiency diseases. Though no accurate data is available, beriberi is reported in the refugees who are dependent on the emergency food aid, rich in carbohydrate and saturated fats. There is a lack of micronutrient supplementation in such diet [5].

When the person is devoid of thiamine, the stores of this vitamin in the body get depleted within a month, after which there are several symptoms such as resting tachycardia, decrease in the deep tendon reflexes, or peripheral neuropathy. Beriberi is categorized into two types: dry beriberi and wet beriberi.

Dry beriberi: When the thiamine deficiency involves the nervous system, it is termed as dry beriberi. This type of beriberi is seen in patients with poor calorie-intake and higher physical inactivity. The manifestations of the disease are peripheral neuropathy (impairment of the sensory, motor or reflex functions of the extremities), or degeneration of the myelin in muscle sheaths.

One of the significant presentations of dry beriberi is Wernicke encephalopathy. In this condition, there is an orderly sequence of symptoms such as vomiting, horizontal nystagmus, fever, ataxia, and progressive mental impairment. All these symptoms lead to Korsakoff syndrome. Only 50% of the patients who reach this stage recover completely [7].

Wet beriberi: When beriberi involves the cardiovascular system, it is referred to as wet beriberi. There is peripheral vasodilation causing high cardiac output. Salt-water retention mediated by renin-angiotensin-aldosterone system is also observed. With vasodilation, the kidneys detects the loss of volume and thus starts conserving the salt.

When salt retention occurs, more fluid is absorbed causing edema of the extremities. This puts extra burden on the heart and it is severely overworked. Parts of the heart, thus, undergo injury and the patient starts showing physical symptoms of tachycardia, edema and myocardial injury.

Shoshin beriberi is a rapid form of wet beriberi causing predominant injury to the heart, and the inability of the heart muscles to fulfill its functions. In this case, edema is absent, however, cyanosis of the hands and feet, tachycardia, and anxiety is observed. If no treatment is initiated, death is almost certain within hours or days [6].

Complications: Some of the severe complications of beriberi are coma, congestive heart failure, psychosis and death.

Correct dose of thiamine through diet daily can help prevent beriberi.

Beriberi is a disease that occurs due to deficiency of thiamine pyrophosphate. Thiamine pyrophosphate is the active form of the vitamin thiamine or vitamin B1. The functions of the active form of thiamine are that it acts as a coenzyme in the metabolism of carbohydrate by decarboxylation of alpha-ketoacids and in the pentose monophosphate pathway.

Thiamine is a water-soluble vitamin (which the body cannot produce) and is concentrated in the skeletal muscles, brain, kidneys, liver and heart. It is excreted by the kidneys. If the proper amount of Vitamin B1 is not taken through diet, it can lead to deficiency of this vitamin. In hyperthyroidism, pregnancy, severe liver disease and lactation, there is an excessive use of the vitamin contributing to the deficiency. Food is an excellent source of vitamin B1. Some of the food-items that are rich in thiamine are whole grain foods, milk and milk products, green leafy vegetables, juices (orange and tomato), and legumes [1] [2].

Patients must know that vitamins are very important for the working of the body. These micronutrients must be provided to the body in adequate amount in order to combat deficiency.

Beriberi is asymptomatic but as it progresses, its manifestations are severe. Alcohol and fad diet worsens the condition in such patients. Once the problem is addressed, the patients are advised to maintain the appropriate diet.