Disease Description (Causes and Symptoms)
- Definition: A disease caused by thiamine (vitamin B1) deficiency. It mainly affects the peripheral and cardiovascular systems, causing decreased muscle strength, sensory abnormalities, gait disturbance, and heart failure.
- Causes: Thiamine deficiency may result from inadequate dietary intake (a diet primarily consisting of refined rice or grains), alcohol dependence, malabsorption (such as after gastrointestinal surgery), prolonged malnutrition or dialysis, or acute intake of large amounts of carbohydrates.
- Pathophysiology: Thiamine acts as a cofactor for energy-metabolism enzymes, including pyruvate dehydrogenase, α-ketoglutarate dehydrogenase, and transketolase. When thiamine is deficient, glucose metabolism is impaired, reducing energy production in tissues—especially nerves and cardiac muscle—and leading to metabolic acidosis, cellular dysfunction, and tissue damage.
- Main symptoms:
- Dry (neurologic) beriberi: Numbness in the hands and feet, decreased sensation, muscle atrophy, muscle weakness, gait disturbance, paralysis of the limbs, muscle pain, and coma (in severe cases)
- Wet (cardiovascular) beriberi: Leg edema, tachycardia, cardiomegaly, pulmonary congestion, and exertional or nocturnal dyspnea caused by congestive heart failure
- Central nervous system-related: Short-term memory impairment, confusion, nystagmus, and Wernicke encephalopathy (acute encephalopathy) → If treatment is delayed, it may progress to Korsakoff syndrome (memory loss and inaccurate memories)
Treatment
- Immediate treatment (principle): Thiamine supplementation
- Recommended regimen provided (general approach): Administer by injection for the first three days to one week (e.g., 100 mg intravenously or intramuscularly once daily for the first 7 days), then switch to oral thiamine (e.g., 10 mg/day) when symptoms improve and continue until complete recovery.
- In severe cases (suspected Wernicke encephalopathy or severe neurologic abnormalities), higher intravenous doses may be used according to hospital guidelines (e.g., some guidelines recommend repeated administration of 200–500 mg IV). The physician determines the route and dosage based on the patient's condition.
- Supportive treatment
- For symptoms of heart failure, diuretics and supportive treatment; oxygen therapy and inpatient observation if necessary
- Nutritional supplementation: Supplement other water-soluble vitamins as well (such as with a multivitamin), and correct magnesium deficiency if present (magnesium is necessary for thiamine function)
- Physical therapy and rehabilitation: Muscle-strength recovery and gait training
- Precautions (during treatment)
- In suspected patients, thiamine must be administered before glucose (administering glucose alone may worsen Wernicke symptoms).
- Response to treatment varies depending on the symptoms: Circulatory and eye-movement symptoms often improve rapidly, while peripheral nerve damage or psychiatric sequelae (Wernicke–Korsakoff syndrome) may recover incompletely or remain permanently.
Checklist Before an Outpatient Visit (Items to Prepare and Example Questions)
- Items to prepare (recommended to bring)
- A list of currently used medications and supplements (including dosage and frequency)
- Recent blood test results (if available), electrocardiogram results (if available), and records of hospitalization or other medical care
- The time symptoms began and how they have progressed (when they worsened), including records of changes in walking, edema, and shortness of breath
- Dietary habits (including staple foods and alcohol consumption), and records of weight changes
- Items useful to record before an outpatient visit
- The location and nature of abnormal sensations (such as numbness or pins and needles), the extent of muscle weakness, and the degree of limitations in daily activities
- Alcohol consumption (daily and weekly), and a history of gastrointestinal surgery or malabsorption
- Situations requiring an immediate emergency-room visit if symptoms worsen: Acute confusion, decreased consciousness, shortness of breath, sudden abnormal heartbeat, or fainting
Examples of General Questions to Ask the Doctor
- When should I expect this medication (thiamine) to start working? What are its side effects?
- In my case, do I need intravenous treatment (inpatient care), or is oral treatment sufficient?
- What is the expected recovery period (prognosis)? How likely are permanent sequelae?
- Which aspects of my lifestyle (diet and alcohol consumption) must I change?
- Should other nutrients (such as magnesium) also be tested or supplemented?
Examples of Disease-Specific Questions
- I frequently consume alcohol. Given my current alcohol consumption and lifestyle, how should I start thiamine supplementation? (Discuss an abstinence plan, supplementation dose, follow-up testing, etc.)
- I still have gait disturbance and weakness in my legs. When should rehabilitation (physical therapy) begin, what are its goals, and what degree of recovery can be expected?
Additional Precautions
- Prevention: Maintain a balanced diet (including thiamine-containing foods such as whole grains, pork, nuts, and legumes), and consider supplementation for high-risk groups (people with chronic alcohol use, malnutrition, or a history of gastrointestinal surgery).
- Complications: Wernicke–Korsakoff syndrome (memory impairment and confusion), permanent peripheral nerve damage, and heart failure (including the risk of death from heart failure) may occur.
- Epidemiologic features: More common in regions where refined rice or other single-food diets are prevalent and among populations with nutritional deficiencies or alcohol dependence (seasonal increases have also been reported).
If you wish, I can organize guidance on prioritizing a hospital visit based on your current symptoms (immediate emergency care, prompt outpatient visit, or routine outpatient visit) and a list of tests that may be expected at the hospital (blood tests, erythrocyte transketolase activity, urinary thiamine measurement, electrocardiogram/chest X-ray, etc.).