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Kidney Function and Other Manifestations of Polycystic Kidney Disease

Exon Publications, Brisbane, Australia

ABSTRACT

Polycystic Kidney Disease (PKD) is a genetic disorder that leads to the formation of numerous fluid-filled cysts in the kidneys and affects other parts of the body. Genetic mutations disrupt normal cellular functions, leading to uncontrolled cell growth and cyst formation. As these cysts expand, they impair the kidneys' ability to filter waste, resulting in chronic kidney disease and potentially end-stage renal disease. PKD also causes issues beyond the kidneys, such as liver cysts, aneurysms, heart problems, and digestive issues. This chapter explores the impact of PKD on kidney function, and the extrarenal manifestations of the disease.

Keywords: Cyst formation mechanisms in polycystic kidney disease; Extrarenal complications of PKD; Growth patterns of kidney cysts in PKD; Impact of PKD on kidney function; Kidney function decline in PKD; Liver cysts in polycystic kidney disease; Mechanisms of cyst growth in PKD; PKD impact on cardiovascular health; Polycystic kidney disease extrarenal manifestations; Role of inflammation in PKD progression

Correspondence: Exon Publications, Brisbane, Australia. books@exonpublications.com

Cite as: Kidney Function and Other Manifestations of Polycystic Kidney Disease. In: Polycystic Kidney Disease: Public Education. Brisbane (AU): Exon Publications, 2024. Online first 2024 May 28. ISBN: 978-0-6458663-8-4.

Doi: https://doi.org/10.36255/kidney-function-other-manifestations-polycystic-kidney-disease

Copyright: Exon Publications.

License: This article is published under Attribution-NonCommercial-NoDerivatives license (BY-NC-ND 4.0) https://creativecommons.org/licenses/by-nc-nd/4.0/

INTRODUCTION

Polycystic Kidney Disease (PKD) significantly impacts the kidneys and other organs in the body. It is a genetic disorder characterized by the development of numerous cysts in the kidneys. Over time, these cysts can grow larger and larger. One of the reasons they grow is because of an increase in fluid secretion into the cysts. The cells lining the cysts pump fluid into the sacs, causing them to expand. As cysts grow, they compress the surrounding kidney tissue, leading to further damage and loss of kidney function. This is why PKD is a progressive disease, meaning it gets worse over time. The growing cysts not only impair the kidneys' ability to filter waste from the blood but can also cause pain and other complications. This chapter aims to provide an understanding of the consequences of PKD on kidney function, and the various ways the disease affects other parts of the body (110).

KIDNEY FUNCTION

PKD has a profound impact on kidney function, often leading to significant health challenges over time. The kidneys are vital organs that filter waste products and excess fluids from the blood, regulate electrolyte levels, and maintain overall fluid balance in the body. In PKD, the development of numerous fluid-filled cysts disrupts these essential functions. These cysts grow and multiply, causing the kidneys to enlarge and lose their ability to work properly.

One of the earliest impacts of PKD on kidney function is an increase in kidney size. As the cysts grow, they push against the normal kidney tissue, causing the kidneys to become larger than usual. Although the kidneys may initially continue to function relatively well, the pressure from the growing cysts gradually damages the healthy kidney tissue.

High blood pressure

As the disease progresses, the growing cysts take up more space and reduce the amount of healthy tissue available to filter waste from the blood. This leads to a decline in kidney function. One of the first signs of this decline is an increase in blood pressure. The kidneys play a crucial role in regulating blood pressure by balancing fluid and salt levels. When they are impaired by PKD, they struggle to perform this function, leading to high blood pressure, or hypertension. High blood pressure is a common and serious complication of PKD, which can further damage the kidneys and increase the risk of heart disease and stroke.

Chronic kidney disease

Another major impact of PKD on kidney function is the gradual loss of the kidneys' filtering ability, leading to chronic kidney disease (CKD). CKD is a condition where the kidneys cannot filter waste and excess fluids efficiently, causing waste products to build up in the blood. Symptoms of CKD may include fatigue, swelling in the legs and feet, nausea, and difficulty concentrating. If left unmanaged, CKD can progress to end-stage renal disease (ESRD), where the kidneys can no longer function on their own.

In addition to affecting kidney function, PKD can also lead to other health problems. For example, the cysts can cause pain and discomfort, particularly in the back and sides. Kidney stones, which are hard deposits of minerals that form in the kidneys, are more common in people with PKD and can cause severe pain and urinary problems.

EXTRARENAL MANIFESTATIONS OF POLYCYSTIC KIDNEY DISEASE

PKD is known for its primary impact on the kidneys, but it also affects other parts of the body. These effects are called extrarenal manifestations, meaning they occur outside the kidneys. One of the most common extrarenal manifestations of PKD is the development of cysts in the liver. These liver cysts are usually not as harmful as kidney cysts, but they can cause discomfort and enlargement of the liver. In some cases, the cysts can become infected or bleed, leading to additional complications. Women with PKD are more likely to develop liver cysts, especially if they have had multiple pregnancies.

Aneurysms

PKD can also affect the blood vessels, leading to an increased risk of aneurysms. An aneurysm is a weakened area in the wall of a blood vessel that can balloon out and potentially burst. This is particularly concerning when it occurs in the blood vessels of the brain, known as intracranial aneurysms. If an intracranial aneurysm ruptures, it can cause a stroke or severe bleeding in the brain, which can be life-threatening.

Heart problems

Heart problems are another extrarenal manifestation of PKD. Individuals with PKD are at a higher risk of developing heart valve abnormalities, such as mitral valve prolapse. This condition occurs when the valve between the heart's left atrium and left ventricle does not close properly, allowing blood to flow backward. Although this condition is usually mild, it can sometimes cause palpitations, chest pain, or shortness of breath.

Gastrointestinal issues

PKD can also affect the gastrointestinal system. Diverticulosis, a condition where small pouches form in the walls of the colon, is more common in people with PKD. These pouches can become inflamed or infected, causing pain and digestive issues. Additionally, some individuals with PKD may experience hernias, which are bulges of tissue that push through a weak spot in the abdominal muscles.

Reproductive health

Reproductive health can also be impacted by PKD. Women with the disease may experience complications during pregnancy, such as high blood pressure or preeclampsia, which can pose risks to both the mother and the baby. It is important for women with PKD to receive regular prenatal care and to be monitored closely throughout their pregnancy.

Other manifestations

Beyond these physical manifestations, PKD can also have a significant impact on mental and emotional health. Living with a chronic condition that affects multiple organs can be challenging and stressful. Individuals with PKD may experience anxiety, depression, or other mental health issues as they cope with the disease. Support from healthcare professionals, family, and support groups can be crucial in managing these emotional challenges.

CONCLUSION

PKD is a complex condition that affects not only the kidneys but also other organs and systems in the body. The formation and growth of cysts in the kidneys are driven by genetic mutations that disrupt normal cellular functions, leading to significant kidney damage over time. This results in chronic kidney disease and can progress to end-stage renal disease, requiring dialysis or a kidney transplant. Beyond the kidneys, PKD can cause liver cysts, aneurysms, heart valve problems, and digestive issues, among other complications.

NOTICE TO THE USER

This article is part of our public education series. It was written by professional medical writers for the public using simple terms based on our medical book Polycystic Kidney Disease and articles indexed in PubMed, and further peer-reviewed for factual accuracy by independent experts. It is intended solely for informational purposes and is not to be considered medical advice. The views and opinions expressed in this article are believed to be accurate at the time of publication, but the publisher, editors, or authors cannot be held responsible or liable for any errors, omissions, or consequences arising from the use of the information contained in this article. The publisher makes no warranties, implicit or explicit, regarding the contents of this article or its use.

COPYRIGHT

The copyright of this article belongs to Exon Publications (Publisher). The electronic version is published under Creative Commons Attribution-NonCommercial-NoDerivs 4.0 (BY-NC-ND 4.0) https://creativecommons.org/licenses/by-nc-nd/4.0/. What does this mean? BY: Credit must be given to the Publisher as the original source. NC: Only noncommercial uses of the work are permitted. ND: No derivatives or adaptations of the work are permitted. For commercial purposes, please contact the Publisher.

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