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Pyridoxine Deficiency Clinical Presentation

  • Author: Richard E Frye, MD, PhD; Chief Editor: George T Griffing, MD  more...
Updated: Jan 15, 2014


Factors that increase the risk for pyridoxine deficiency [12]

  • Advanced age
  • Medical conditions
    • Severe malnutrition
    • Sickle cell disease
    • Inflammatory conditions[6, 7]
    • Rheumatoid arthritis[6]
    • Hospitalization
    • Celiac disease
    • Hepatitis and extrahepatic biliary obstruction
    • Hepatocellular carcinoma
    • Chronic renal failure
    • Kidney transplant[14]
    • Hyperoxaluria types I and II
    • High serum alkaline phosphatase level, such as in cirrhosis and tissue injury
    • Catabolic state
  • Medical procedures
    • Hemodialysis
    • Peritoneal dialysis
    • Phototherapy for hyperbilirubinemia
  • Medications
    • Cycloserine
    • Hydralazine
    • Isoniazid
    • D-penicillamine
    • Pyrazinamide
  • Social-behavioral conditions
    • Excessive alcohol ingestion (except for pyridoxine-supplemented beer)
    • Tobacco smoking
    • Severe malnutrition
  • Other risk factors
    • Poisoning, such as Gyromitra mushroom poisoning
    • Perinatal factors, such as a pyridoxine-deficient mother
    • Inherited conditions, such as pyridoxine-dependent neonatal seizures[8, 9, 10]

Other patient history

See the list below:

  • Sideroblastic anemia
  • Pregnancy - Pregnancy can cause a pyridoxine-deficient state; however, a change in the ratio of plasma PLP to pyridoxal does occur, thereby falsely suggesting a deficiency state if only serum PLP is measured.
  • Physical exercise - This may transiently increase plasma PLP levels.

Symptoms and conditions associated with low pyridoxine levels

See the list below:

  • General
    • Weakness
    • Dizziness
    • Inflammation[6, 7]
  • Cardiovascular
    • Atherosclerosis
    • Early myocardial infarction
    • Early stroke[7]
    • Recurrent venous thromboembolism
  • Hematologic - Fatigue resulting from anemia is an example.
  • Peripheral nervous system
    • Bilateral, distal limb numbness (appears early)
    • Bilateral, distal limb burning paresthesia (replaces numbness later in the course)
    • Distal limb weakness (rare)
  • Central nervous system (CNS)
    • Depression
    • Irritability
    • Confusion
    • Generalized seizures
    • White matter lesions
  • Gastrointestinal
    • Anorexia
    • Vomiting

Symptoms and conditions associated with secondary niacin deficiency (ie, pellagra)

See the list below:

  • Skin
    • Erythematous itching and burning
    • Blisters and vesicles
    • Hyperpigmentation and thickening
  • CNS
    • Depression
    • Anxiety
    • Irritability
    • Disorientation
    • Stupor
    • Coma
  • Gastrointestinal
    • Anorexia
    • Nausea
    • Abdominal discomfort and pain
    • Glossitis
    • Diarrhea


Physical examination findings may include the following:

  • Oral
    • Glossitis
    • Cheilosis
  • Dermatologic - Seborrheic dermatitis is an example.
  • Adult, neurologic
    • Distal limb numbness and weakness
    • Impaired vibration and proprioception
    • Preserved pain and temperature
    • Sensory ataxia
    • Generalized seizures
  • Neonatal and young infant, neurologic
    • Hypotonia
    • Irritability
    • Restlessness
    • Focal, bilateral motor, or myoclonic seizures
    • Infantile spasms
  • Secondary niacin deficiency
    • Skin - Dermatitis over sun-exposed areas; blisters and vesicles; beefy red, raw tongue
    • CNS - Confusion, dementia, disorientation, rigid tone, primitive reflexes


See the list below:

  • Pyridoxine intake is reduced in cases of severe malnutrition.
  • Pyridoxine absorption is reduced in elderly persons and in patients with intestinal disease or who have undergone surgery.
  • Pyridoxine clearance is enhanced by liver disorders, such as hepatitis, and by several medications.
  • Pyridoxine breakdown is enhanced in conditions associated with increased alkaline phosphatase levels.
  • Hematologic pathway enzymes with a low affinity for pyridoxine cause a microcytic-hypochromic pyridoxine-responsive anemia (ie, sideroblastic anemia). An X-linked inherited condition is observed in carrier females and affected males. An autosomal form of this disorder has been reported in a single family. Long-term alcohol ingestion and iatrogenically induced deficiencies can also result in this type of anemia.[15]
  • Hydrazones from isoniazid and certain mushrooms bind PLP to form isoniazid-hydrazone complexes, resulting in decreased pyridoxal availability for use in other reactions.
  • Pyridoxine-dependent seizures are caused by pyridoxine complexing with an excessive amount of Δ1 –piperideine 6-carboxylate, resulting in a pyridoxine deficiency. Excessive Δ1 –piperideine 6-carboxylate results from a deficiency in the enzyme α-aminoadipic semialdehyde dehydrogenase due to a mutation in the ALDH7A1 (antiquitin) gene.[16]
  • Low maternal pyridoxine levels can cause pyridoxine-responsive seizures.[11]
  • Excessive maternal pyridoxine supplementation can induce pyridoxine turnover, resulting in a higher requirement. Pyridoxine-responsive seizures may result.
  • Endogenous or exogenous estrogens can alter tryptophan metabolism by directly inhibiting kynureninase, a proximal, potentially rate-limiting enzyme in tryptophan metabolism. A pyridoxine-dependent compound, kynureninase is the same enzyme that is inhibited in the pyridoxine-deficient state. Altered tryptophan metabolism resulting from high estrogen levels may be attributed to a pyridoxine deficiency if the former is not considered.
Contributor Information and Disclosures

Richard E Frye, MD, PhD Associate Professor of Pediatrics, University of Arkansas for Medical Sciences College of Medicine; Director of Autism Research, Child and Behavioral Neurologist, Arkansas Children's Hospital Research Institute

Richard E Frye, MD, PhD is a member of the following medical societies: American Academy of Neurology, American Academy of Pediatrics, Child Neurology Society, International Neuropsychological Society

Disclosure: Nothing to disclose.


Serge A Jabbour, MD, FACP, FACE Professor of Medicine, Division of Endocrinology, Diabetes and Metabolic Diseases, Jefferson Medical College of Thomas Jefferson University

Serge A Jabbour, MD, FACP, FACE is a member of the following medical societies: American Association of Clinical Endocrinologists, American College of Physicians-American Society of Internal Medicine, American Diabetes Association, American Medical Association, American Thyroid Association, Endocrine Society, Pennsylvania Medical Society

Disclosure: Nothing to disclose.

Specialty Editor Board

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Received salary from Medscape for employment. for: Medscape.

Chief Editor

George T Griffing, MD Professor Emeritus of Medicine, St Louis University School of Medicine

George T Griffing, MD is a member of the following medical societies: American Association for the Advancement of Science, International Society for Clinical Densitometry, Southern Society for Clinical Investigation, American College of Medical Practice Executives, American Association for Physician Leadership, American College of Physicians, American Diabetes Association, American Federation for Medical Research, American Heart Association, Central Society for Clinical and Translational Research, Endocrine Society

Disclosure: Nothing to disclose.

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