Introduction:
Chronic kidney disease is a condition characterized by loss of kidney function. It is a significant and majorly present disease. The kidneys are a vital organ of the body mainly to filter waste products and remove toxins, they also help in homeostasis and regulation. They also produce hormones to control blood pressure and other functions. Chronic kidney disease results when kidney function declines, and waste products accumulate. Severe end-stage kidney disease patients require a kidney transplant.
In chronic kidney disease patients, there is a high tendency to develop gastrointestinal symptoms like nausea, vomiting, indigestion, feeling full quickly, loss of appetite, and weight loss. Diarrhea or constipation may also be seen, accompanied by pain. While kidney impairment is the major anthology in patients with chronic kidney disease, there is growing evidence that neurological causes have an important role in prompting gastrointestinal symptoms. These symptoms appear to have a neurological connection as there is an evident linkage. This article intends to explore the neurological causes of gastrointestinal symptoms in chronic kidney disease patients.
How Does the Neuroanatomy of the Gut-Brain Axis Work?
The gut-brain axis is a system of communication that connects the gastrointestinal tract and central nervous system. There is an extensive network of neurons in the gut wall, which helps regulate all the functions of the gut system, like motility, secretions, and regulation of function. The central nervous system includes the higher centers which modulate and help the processes reach their adequate pathways. This, along with the autonomic nervous system, has an important duty to control gastrointestinal motility and function, the flow of blood, adequate pain, and sensitivity sensations.
What Are the Gastrointestinal Symptoms of Chronic Kidney Disease?
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Gastroparesis: Gastroparesis refers to the delay in emptying of the stomach. This could be a result of the effect of toxins on the gastric tract or an alteration in the hormonal levels. There is also an autonomic neural issue as a possible causative factor.
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Dysfunction: Bowel dysfunction could result in constipation, diarrhea, or a combination of both. Constipation is difficulty in passing stool and straining. Diarrhea means the passing of loose stools, a result of an increase in the permeability of the intestine. Both these gastrointestinal issues are highly discomforting and painful for the patient.
- Increased Sensitivity: Increased sensitivity in the gastrointestinal tract leads to extreme pain and discomfort. This is mainly attributed to inflammation of the neurogenic cause. The nerve pathways can get hypersensitized or even alteration in the processing of pain pathways can occur.
What Are the Neurological Causes of Gastrointestinal Symptoms in Chronic Kidney Disease?
There is a neurological dimension in most of the diseases and their symptoms. This is because there are numerous intricate communications between the various nervous systems and all organs. Any kind of disruption in these results in issues in the gastrointestinal and renal system dysfunction. Some neural causes for gastrointestinal symptoms in chronic kidney disease include:
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Uremic Neuropathy: When there is an excess of urea toxins in the body, especially in chronic kidney disease, it results in a condition where there is damage to the nerves in the peripheral system. This is called uremic neuropathy. This can lead to dysfunction in the gastrointestinal motility and secretions. Nerve damage through this neuropathy can further result in impaired bowel function and exacerbation of symptoms like bloating, dysmotility, nausea, and vomiting.
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Neural Inflammation: Systemic inflammation leads to increased stimulation of all the pathways related to pain, and discomfort. Chemical mediators have a major role in disrupting the normal neurotransmitter function. This leads to dysmotility in the gut leading to further gastrointestinal symptoms. Chronic kidney disease is also associated with significant systemic inflammation; this can extend to a neural system within the gastrointestinal tract, too. There is a complex linkage between neural pathways and neurotransmitters which have a role in exacerbating the disease symptoms.
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Metabolic Abnormalities: In chronic kidney disease, it is common to have a major imbalance in the electrolyte levels in the body. This leads to acid-base disturbances and many hormonal alterations. This affects the overall functioning of the system. An increase in potassium levels, known as hyperkalemia has a major influence on the excitability of the muscles and release of neurotransmitters. When this happens, a myriad of gastrointestinal symptoms also arise.
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Hormones: Alterations in insulin and glucagon, commonly seen in diabetics have a major influence on gut motility and nutrient absorption. They affect energy consumption and utilization, too. This further leads to gut issues seen in chronic kidney disease. So, hormones also have a neutral effect on the gastrointestinal system in patients with renal disease.
What Are the Therapeutic Implications?
Understanding the neurological cause of chronic kidney disease and gastrointestinal symptoms can have a significant effect on patient therapy. A few examples are:
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Pharmacotherapy: Medications such as Gabapentinoids and tricyclic antidepressants may be indicated by the healthcare provider to manage the neurological component of the abdominal pain and discomfort. Along with that, medicines like Metoclopramide can also help enhance motility and reduce gastrointestinal problems.
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Diet Modification: Taking medications with the intent to reduce toxins like uremic and phosphates can help reduce the other symptoms, too.
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Stress Management: To help with coping with the symptoms, it is advised for the patient to take stress management and behavioral therapies. Practicing mindfulness and meditation also helps reduce the increased nerve stimulation and promotes better digestion and gut health.
Conclusion
The neurological causes of gastrointestinal symptoms in chronic disease are numerous and complex. There is a significant association between the neurons in the gut, central nervous system, autonomic nervous system, and the gastrointestinal system as a whole. There is a need to understand these mechanisms with the intent to figure out the exact cause for exacerbated symptoms seen in chronic kidney patients. Finding the cause and helping in its intervention will help relieve the patient's symptoms and improve patient outcomes to a great extent. A multidisciplinary approach focusing on nephrology, gastroenterology, and neurology is required to diagnose and manage symptoms from a comprehensive perspective and treat the patient as a whole.
