Beriberi pathophysiology

Jump to navigation Jump to search

Beriberi Microchapters

Home

Patient Information

Overview

Historical Perspective

Classification

Pathophysiology

Causes

Differentiating Beriberi from other Diseases

Epidemiology and Demographics

Risk Factors

Screening

Natural History, Complications and Prognosis

Diagnosis

Diagnostic Study of Choice

History and Symptoms

Physical Examination

Laboratory Findings

Electrocardiogram

X-ray

Echocardiography and Ultrasound

CT scan

MRI

Other Imaging Findings

Other Diagnostic Studies

Treatment

Medical Therapy

Surgery

Primary Prevention

Secondary Prevention

Cost-Effectiveness of Therapy

Future or Investigational Therapies

Case Studies

Case #1

Beriberi pathophysiology On the Web

Most recent articles

Most cited articles

Review articles

CME Programs

Powerpoint slides

Images

American Roentgen Ray Society Images of Beriberi pathophysiology

All Images
X-rays
Echo & Ultrasound
CT Images
MRI

Ongoing Trials at Clinical Trials.gov

US National Guidelines Clearinghouse

NICE Guidance

FDA on Beriberi pathophysiology

CDC on Beriberi pathophysiology

Beriberi pathophysiology in the news

Blogs on Beriberi pathophysiology

Directions to Hospitals Treating Beriberi

Risk calculators and risk factors for Beriberi pathophysiology

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Abdelrahman Ibrahim Abushouk, MD[2]

Overview

The lack of thiamine pyrophosphate (TTP) impairs the functions of four enzymes involved in energy production and neurotransmitter synthesis, namely pyruvate dehydrogenase, α-ketoglutarate dehydrogenase, transketolase, and branched-chain α-ketoacid dehydrogenase. Energy deprivation and deficient neurotransmitter synthesis probably explain the neural and cardiac dysfunctions, observed with beriberi.

Pathophysiology

Physiology

The active form of thiamine, "thiamine pyrophosphate or TTP" is an essential cofactor for four enzymes i.e. these enzymes use TTP to transfer an aldehyde unit to their substrates in various metabolic pathways.[1] These enzymes are:

Pathogenesis

Deficiency of TTP leads to impaired activity of the four aforementioned enzymes, causing energy deprivation and deficient synthesis of acetylcholine, glutamate and GABA neurotransmitters. Thiamine deficiency mainly affects the tissues that require high amounts of energy (ATP) as the heart and the brain. It is believed that energy deprivation and deficient neurotransmitter synthesis are responsible for the neural defects in dry beriberi. Other studies revealed non-coenzyme functions for thiamine in the brain as maintaining cell membrane stability and possibly acting as a trophic factor.[2] Although energy deprivation is also believed to be the main mechanism of wet beriberi, the full pathophysiological picture of this subtype is not yet fully elucidated.

Genetics

  • In most cases, beriberi is a sporadic condition with no family history. However, a rare condition known as genetic beriberi may prevent the body from absorbing thiamine.
  • A study by Bravata et al. could not identify specific mutations in thiamine transporter genes in individuals with sporadic beriberi.[3] Some studies indicated the possibility of genetic predisposition for Wernicke-Korsakoff syndrome.[4]

Associated Conditions

Since beriberi is common in countries with unbalanced food sources in terms of contained nutrients, other vitamin deficiencies may be associated.

Gross Pathology

Late stage paralysis with atrophy in dry beriberi. [6]

Microscopic Pathology

There are no specific microscopic features in tissues affected with beriberi. However, in advanced stages, the tissues might show the microscopic features of:

References

  1. Singleton CK, Martin PR (2001). "Molecular mechanisms of thiamine utilization". Curr Mol Med. 1 (2): 197–207. doi:10.2174/1566524013363870. PMID 11899071.
  2. Bâ A (2008). "Metabolic and structural role of thiamine in nervous tissues". Cell Mol Neurobiol. 28 (7): 923–31. doi:10.1007/s10571-008-9297-7. PMID 18642074.
  3. Bravatà V, Minafra L, Callari G, Gelfi C, Edoardo Grimaldi LM (2014). "Analysis of thiamine transporter genes in sporadic beriberi". Nutrition. 30 (4): 485–8. doi:10.1016/j.nut.2013.10.008. PMID 24607307.
  4. Blass JP, Gibson GE (1979). "Genetic factors in Wernicke-Korsakoff syndrome". Alcohol Clin Exp Res. 3 (2): 126–34. doi:10.1111/j.1530-0277.1979.tb05286.x. PMID 391073.
  5. Shible AA, Ramadurai D, Gergen D, Reynolds PM (2019). "Dry Beriberi Due to Thiamine Deficiency Associated with Peripheral Neuropathy and Wernicke's Encephalopathy Mimicking Guillain-Barré syndrome: A Case Report and Review of the Literature". Am J Case Rep. 20: 330–334. doi:10.12659/AJCR.914051. PMC 6429982. PMID 30862772.
  6. https://upload.wikimedia.org/wikipedia/commons/8/88/Late_stage_of_paralysis_with_atrophy_in_dry_beriberi.jpg Attribution: W. Hamilton Jefferys [Public domain
  7. Chandrakumar A, Bhardwaj A, 't Jong GW (2018). "Review of thiamine deficiency disorders: Wernicke encephalopathy and Korsakoff psychosis". J Basic Clin Physiol Pharmacol. 30 (2): 153–162. doi:10.1515/jbcpp-2018-0075. PMID 30281514.


Template:WikiDoc Sources