Causes and epidemiology of deficiency
In medical practice, Acidum pantothenicum hypovitaminosis is diagnosed extremely rarely. The main and virtually sole etiological cause of this pathological condition is the alimentary factor, i.e., a permanent lack of the nutrient in the daily diet.
Since this chemical compound is found in almost all common foods, developing a pronounced deficiency on a standard diet is virtually impossible.
Pathogenesis and metabolic disorders
When pantothenic acid deficiency develops, critical biochemical processes in the body are impaired:
- Normal synthesis of cholesterol is disrupted.
- Production of vital glucocorticoids suffers.
- The synthesis rate of protective immunoglobulins (Ig) drops.
- Tissue repair processes deteriorate, and the overall tensile strength of collagen fibers decreases, leading to pronounced impaired regeneration.
Clinical manifestations in organ systems
Generalized pantothenic acid deficiency causes multiorgan pathology:
- Nervous system: sleep disorders, chronic fatigue, persistent headaches, unpleasant paresthesias, nerve inflammation (neuritis), and even paralysis occur.
- Endocrine status: irreversible degenerative changes develop in the adrenal cortex, triggering the clinical picture of hypocorticism.
- Cardiovascular system: dystrophic changes accompanied by cardiac arrhythmias are registered in the myocardium.
- Gastrointestinal tract: patients lose appetite (anorexia) and suffer from cavitary and membrane digestion disorders.
- Immune system: against the background of marked immunosuppression, susceptibility to severe inflammatory and infectious diseases increases sharply. Specific renal function impairments are also noted.
Safety and toxicity
An important feature of pantothenic acid is its complete atoxicity. Even when this substance enters the body in very high doses, it does not lead to negative consequences. Modern medical literature does not describe a single case of intoxication or overdose with this vitamin.
Briefly: answers to topical questions
Which vital coenzymes does pantothenic acid form a part of?
Pantothenic acid is a precursor vitamin for the synthesis of the essential acylation coenzyme — coenzyme A.
- Coenzyme A (CoA / HS-CoA) is a complex compound whose active form contains an adenylic nucleotide, a thioethanolamine residue, and pantothenic acid (in the form of pantetheine).
The process of synthesis of this coenzyme in the body includes phosphorylation of pantothenic acid using ATP, addition of cysteine to form 4'-phosphopantetheine, and subsequent adenylylation.
What is the average daily requirement of an adult for pantothenic acid?
The average daily requirement of the body for pantothenic acid is about 10 mg.
The vitamin is ubiquitous in nature and is contained in sufficient quantities in almost all foods (yeast, liver, egg yolk, fish, milk, meat, legumes, green parts of plants). In addition, part of the required amount of the vitamin is synthesized by the normal intestinal microflora. This is precisely why pathological conditions associated with pantothenic acid deficiency are very rare.
In which metabolic reactions does the active form of vitamin B5 participate?
The active form of vitamin B5 (coenzyme A) participates in enzymatic reactions that catalyze the activation and transfer of acyl and acetyl groups.
Main metabolic reactions:
- Formation of active forms of fatty acids.
- Activation of acetate (acetic acid) with the formation of a high-energy bond in the acetyl-CoA molecule.
- Oxidative decarboxylation of $\alpha$-keto acids (pyruvic and $\alpha$-ketoglutaric) as part of the corresponding multienzyme dehydrogenase complexes.
Pantothenic acid is everywhere (παντόθεν — from everywhere): it is always present in food, and its deficiency hits the nerves, adrenals, and heart!
Class and exam questions
Why is vitamin B5 deficiency so rare?
Pantothenic acid deficiency is practically never encountered in clinical practice, as this vitamin is found in almost all foods.
What changes in the endocrine system are caused by B5 deficiency?
The deficiency causes degenerative changes in the adrenal cortex, leading to the development of hypocorticism and decreased synthesis of glucocorticoids.
Is an excess of pantothenic acid dangerous in case of overdose?
No, excess vitamin B5 is completely non-toxic even in high doses; cases of intoxication are not described in medical practice.
What else to study on this topic
- Synthesis of mineralocorticoids and catecholamines
- Mechanisms of hypocorticism development in B5 deficiency
- Disorders of cavitary and membrane digestion
- Pathogenesis of myocardial dystrophy in hypovitaminosis
- The role of pantothenic acid in immunoglobulin synthesis
Master the entire topic in the "Pathophysiology" course
This is a summary. The course covers everything tested in classes and exams.
- Complete study guide on "Vitamin B5" and 4,913 other subject pages
- Assignments and quizzes after every topic — just like in a colloquium
- AI tutor answers questions on the topic anytime
- 135 video lessons on the subject
Other topics in "Chapter 14. Vitamin Metabolism Disorders"
Free video lessons: pathophysiologyShort lessons with lecture notes — no registration required.
Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.