History and Physical Examination
Most patients have no symptoms and signs of thiamine deficiency; therefore, it must be suspected in the appropriate clinical setting. Early symptoms and signs are often nonspecific and vague, such as fatigue. However, high-output cardiac failure should prompt investigation of thiamine deficiency as a cause. The same applies to neuropathic symptoms, particularly in the distal extremities.
Neurologic signs and symptoms of thiamine deficiency are as follows [11] :
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Poor memory, irritability, sleep disturbance
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Wernicke encephalopathy, [12] Korsakoff syndrome
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Bilateral, symmetrical lower extremity paresthesias, burning pain
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Muscle cramps
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Decreased vibratory position sensation
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Absent knee and ankle jerk
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Muscle atrophy
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Foot drop (late stage)
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Nystagmus (early sign) [39]
A study from Singapore, by Saini et al, reported that while Guillain-Barré syndrome (GBS) is an important cause of acute flaccid paralysis, thiamine deficiency should be considered an important differential diagnosis, particularly in patients with a history of dietary deprivation and incarceration. [38]
Cardiovascular signs and symptoms are as follows:
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Tachycardia
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Chest pain
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Wide pulse pressure
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Heart failure [13] (orthopnea with or without edema, warm skin due to vasodilation)
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Hypotension, shock
Gastroenterologic signs and symptoms are as follows:
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Anorexia
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Abdominal discomfort
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Constipation
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Dysphagia [14]
Infantile beriberi signs and symptoms are as follows [15] :
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CHF
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Aphonia
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Absent deep tendon reflex
The aforementioned study by Saini et al indicated that although the acute presentation of thiamine deficiency is similar to the presentation of GBS, thiamine deficiency is the more likely disorder when patients exhibit the following [38] :
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Subacute symptom evolution, with symptom evolution over weeks or more
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Presence of nystagmus and cerebellar dysfunction
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Encephalopathy (particularly if specific features of Wernicke disease/Korsakoff psychosis exist)
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Disproportionate vocal cord dysfunction, with paucity of other cranial nerve involvement
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Optic neuropathy
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Signs of volume overload
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Unexplained serum lactate elevation
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Normal cerebrospinal fluid protein
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Absence of sural sparing pattern on nerve conduction studies
A study by Mifsud et al described the characteristics of 56 cases of thiamine deficiency that were seen at a French tertiary hospital. A history of alcohol abuse was found in 45 patients (80%), and while neurologic symptoms were the basis for diagnosis in the majority of individuals, there were frequent instances of nonspecific and digestive symptoms. Moreover, the criteria for malnutrition were fulfilled in 34% of patients. Of the 54% of patients in whom brain magnetic resonance imaging (MRI) scans were performed, abnormal scans were found in 63% of cases. [39]
A study by Isenberg-Grzeda et al indicated that thiamine deficiency may be a frequent occurrence among inpatients with cancer, even in those who are of normal weight or overweight, lack other vitamin deficiencies, and are receiving multivitamin supplements. The single-center study found thiamine deficiency in 55.3% of 217 patients, with risk factors for the deficiency including active cancer treatment and fluorouracil-based chemotherapy. [40]
A literature review by Jain et al comparing the incidence of thiamine deficiency in patients with heart failure to that in controls reported an odds ratio of 2.53, with possible reasons for the deficiency in heart failure including diuretic use, dietary changes, and alterations in the absorption and metabolism of thiamine. The literature also indicated that thiamine supplementation may improve symptoms and ejection fraction in patients with heart failure. [41]
Alcoholism
Persons with chronic alcoholism have low thiamine intake, impaired thiamine uptake and storage, accelerated destruction of thiamine diphosphate, and varying degrees of energy expenditure. Alcohol is a direct neurotoxin. The effects on the body's supply of thiamine and on brain tissue are detrimental. Persons with known alcoholism should be administered parenteral thiamine as a routine action when they present to a medical facility.
Dieting
A patient’s dieting history also may hold a clue regarding thiamine deficiency. Fad diets often do not contain the necessary amounts of thiamine.
Dialysis and high energy consumption
Dialysis also robs thiamine from the circulation. In addition, states of high energy consumption, such as hyperthyroidism, pregnancy, or severe illness, require more thiamine and other nutrients.
Bariatric weight-loss surgery
Persons with a history of gastric bypass may also have beriberi. [24, 42, 43] For bariatric surgery patients, it is believed that a deficiency occurs primarily during the first 6 months after surgery, when individuals undergo the most rapid weight loss.
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Beriberi in an adult patient.
Tables
Population |
Age |
Allowance, mg/day |
Recommended Dietary Allowances (RDAs) |
||
Boys |
9-13 years |
0.9 |
Men |
>14 years |
1.2 |
Girls |
9-13 years |
0.9 |
Women |
14-18 years |
1.0 |
Women |
>19 years |
1.1 |
Pregnant/lactating women |
. . . |
1.4 |
Children |
1-3 years |
0.5 |
Children |
4-8 years |
0.6 |
Adequate Intakes (AIs) |
||
Infant |
0-6 months |
0.2 |
Infant |
7-12 months |
0.3 |
