What are the pathologies associated with tryptophan (an essential amino acid) deficiency?

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From the Research

Tryptophan deficiency can lead to several significant pathologies, most notably pellagra, characterized by dermatitis, diarrhea, dementia, and potentially death if untreated, as highlighted in a recent study 1. The pathologies originating from tryptophan deficiency are multifaceted and can impact various body systems. Some of the key conditions associated with tryptophan deficiency include:

  • Pellagra, a systemic disturbance caused by a cellular deficiency of niacin, resulting from inadequate dietary nicotinic acid and/or its precursors, the essential amino-acid tryptophan 2
  • Depression, anxiety, irritability, and cognitive impairments due to reduced serotonin synthesis
  • Sleep disturbances as melatonin production becomes compromised
  • Immune dysfunction since tryptophan is necessary for proper immune cell function and regulation
  • Protein synthesis disruptions leading to growth retardation in children and muscle wasting in adults

The diagnosis of pellagra is based on the patient's history and the presence of "3 D syndrome": dermatitis, diarrhea, and dementia, as noted in a study published in 2020 3. The treatment of pellagra consists of exogenous administration of niacin or nicotinamide, which can cure the condition, as well as topical management of skin lesions with emollients to reduce discomfort 2. It is essential to prioritize tryptophan-rich foods, such as turkey, chicken, eggs, cheese, fish, tofu, and legumes, in the diet to prevent tryptophan deficiency and its associated pathologies, as emphasized in a 2021 review 4. In severe cases, tryptophan supplements may be necessary under medical supervision. The underlying mechanism involves tryptophan's role as an essential amino acid that cannot be synthesized by the body and must be obtained through diet, making adequate intake crucial for preventing these pathological conditions.

References

Research

[Pellagra].

Sante (Montrouge, France), 2005

Research

Pellagra, an Almost-Forgotten Differential Diagnosis of Chronic Diarrhea: More Prevalent Than We Think.

Nutrition in clinical practice : official publication of the American Society for Parenteral and Enteral Nutrition, 2020

Research

Pellagra a review exploring causes and mechanisms, including isoniazid-induced pellagra.

Photodermatology, photoimmunology & photomedicine, 2021

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This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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