Pyrophosphate is the biologically active form of vitamin B₁.

Thiamine dietary deficiency from excess of polished rice can cause beriberi. 

Alcoholism.

 

 

 

 

Deficiencies of thiamine in chronic alcoholics are related to Wernicke–Korsakoff syndrome, which is characterized by loss of memory, lackadaisical behavior, and a continuous rhythmic movement of the eyeballs. 
  • Thiamine (vitamin B₁) reserves may be depleted within several weeks of inadequate dietary intake or malabsorption 3
  • Severe deficiency can lead to Wernicke encephalopathy, Korsakoff syndrome, and/or beriberi, which are relatively uncommon in the United States 3
    • Beriberi is typically the result of prolonged, mild to moderate deficiency; it is the most common manifestation in developing countries 4 5
    • Wernicke encephalopathy most commonly results from severe short-term thiamine deficiency; if untreated, it progresses to Korsakoff syndrome 4

  • Wernicke encephalopathy is a medical emergency and can result in permanent brain damage or death if not treated emergently; immediately administer high-dose IV thiamine 3 times daily for at least 3 to 5 days or until clinical improvement ceases 1 2

 

 

Where you get them: Most people get thiamine from breakfast cereals and whole grains. Riboflavin can be found in:

  • whole grains
  • milk
  • eggs
  • dark green vegetables

Get your daily servings of green vegetables with this green smoothie.

Why you need them: Deficiencies in thiamine and riboflavin generally don’t pose a problem in the United States. This is due to the fact that many foods, such as milk and whole-grain cereals, are fortified with the vitamins. It can become an issue with people who misuse alcohol, however, presenting symptoms such as confusion and cracks along the sides of the mouth.

 

 

 

 

 A severe and chronic form is known as beriberi.[1][5] There are two main types in adults: wet beriberi, and dry beriberi.[1] Wet beriberi affects the cardiovascular systemresulting in a fast heart rate, shortness of breath, and leg swelling.[1] Dry beriberi affects the nervous system resulting in numbness of the hands and feet, confusion, trouble moving the legs, and pain.[1] A form with loss of appetite and constipation may also occur.[3]Another type, acute beriberi, is found mostly in babies and presents with loss of appetite, vomiting, lactic acidosis, changes in heart rate, and enlargement of the heart.[6]

Risk factors include a diet of mostly white ricealcoholismdialysis, chronic diarrhea, and taking high doses of diuretics.[1][4] Rarely it may be due to a genetic condition which results in difficulties absorbing thiamine found in food.[1] Wernicke encephalopathy and Korsakoff syndrome are forms of dry beriberi.[4] Diagnosis is based on symptoms, low levels of thiamine in the urine, high blood lactate, and improvement with treatment.[7]

Treatment is by thiamine supplementation, either by mouth or by injection.[1] With treatment symptoms generally resolve in a couple of weeks.[7] The disease may be prevented at the population level through the fortification of food.[1]

Thiamine deficiency is rare in the United States.[8] It remains relatively common in sub-Saharan Africa.[2] Outbreaks have been seen in refugee camps.[4] Thiamine deficiency has been described for thousands of years in Asia and became more common in the late 1800s with the increased processing of rice.[9]

 

B 1 (thiamine) Wet beriberi (high-output cardiac failure), dry beriberi (peripheral neuropathy),

 

Wernicke-Korsakoff syndrome (eye movement disorders, ataxia and impaired memory)

Deficiencies of thiamine in chronic alcoholics are related to Wernicke–Korsakoff syndrome,

which is characterized by loss of memory, lackadaisical behavior, and a continuous rhythmic movement of the eyeballs. 

Wernicke’s encephalopathy (temporal lobe) - ataxia, nystagmus
Korsakoff (Mammilary bodies) - confabulation, psychosis

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Symptoms include loss of appetite, weakness, pain in the limbs, shortness of breath, and swollen feet or legs.
Treatments include B-1 supplements and eating more B-1-rich foods, such as whole-grain cereals, beans, and beef.

 

  • Patients who are alcohol dependent and malnourished, have severe liver disease or alcohol withdrawal, or are hospitalized for trauma, head injury, or acute illness are at high risk for developing Wernicke encephalopathy; treat prophylactically with high doses of parenteral thiamine
  • Initiate prompt thiamine replacement in patients with beriberi
  • After initial parenteral therapy, continue long-term oral thiamine maintenance therapy for several months or indefinitely

 

  • Consider Wernicke encephalopathy in any intoxicated patient who does not recover fully from intoxicated state
  • Always administer thiamine before glucose in a patient with suspected Wernicke encephalopathy, particularly in a patient who is intoxicated or who abuses alcohol, presenting with hypoglycemia
    • Administration of glucose without thiamine can precipitate or worsen Wernicke encephalopathy

 

 

Complications of Injecting Drug Use

  • Local problems—Abscess (Figures 240-2 
    Image not available.

    A 32-year-old woman with type 1 diabetes developed large abscesses all over her body secondary to injection of cocaine and heroin. Her back shows the large scars remaining after the healing of these abscesses. (Courtesy of ­Richard P. Usatine, MD.)

    and 240-3; Abscess), cellulitis, septic thrombophlebitis, local induration, necrotizing fasciitis, gas gangrene, pyomyositis, mycotic aneurysm, compartmental syndromes, and foreign bodies (e.g., broken needle parts) in local areas.2
    • IDUs are at higher risk of getting methicillin-resistant Staphylococcus aureus(MRSA) skin infections that the patient may think are spider bites (Figure 240-4).
    • Some IDUs give up trying to inject into their veins and put the cocaine directly into the skin. This causes local skin necrosis that produces round atrophic scars (Figure 240-5).
  • IDUs are at risk for contracting systemic infections, including HIV and hepatitis B or hepatitis C.
    • Injecting drug users are at risk of endocarditis, osteomyelitis (Figures 240-6and 240-7), and an abscess of the epidural region. These infections can lead to long hospitalizations for intravenous antibiotics. The endocarditis that occurs in IDUs involves the right-sided heart valves (see Chapter 50, Bacterial Endocarditis).2 They are also at risk of septic emboli to the lungs, group A β-hemolytic streptococcal septicemia, septic arthritis, and candidal and other fungal infections.

 

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