Cystic Fibrosis Kidney Disease: 10 Tips for Clinicians

Increased longevity in people with cystic fibrosis (CF) means that more people are surviving long enough to develop kidney complications. Nephrologists and their colleagues now face a steep learning curve as many of them encounter patients with CF related kidney disease (CFKD) for the first time. This article presents perspectives from a medical sociologist with CF on what renal health professionals should know about people with CFKD. It outlines challenges that people with CFKD as they age, framing these struggles as opportunities for clinicians to help these unique patients achieve and maintain their best possible quality of life.

Increased longevity in people with cystic fibrosis (CF) means that more people are surviving long enough to develop kidney complications. Nephrologists and their colleagues now face a steep learning curve as many of them encounter patients with CF related kidney disease (CFKD) for the first time. This article presents perspectives from a medical sociologist with CF on what renal health professionals should know about people with CFKD. It outlines challenges that people with CFKD as they age, framing these struggles as opportunities for clinicians to help these unique patients achieve and maintain their best possible quality of life.
Keywords: cystic fibrosis, aging, illness management, patient perspectives, best practices Caring for people who are aging with cystic fibrosis (CF) presents unique challenges for kidney health professionals (1). Many people thriving with CF overall still develop chronic kidney disease as we grow older (2). Managing these issues now constitutes a critical component of healthy aging with CF.
I recently turned 34, which once would have been quite old for a CF patient (3). I am generally doing quite well, but have had symptoms of CF related kidney disease (CFKD) since at least my early 20s. These may include generalized chronic kidney disease (abnormal kidney function) and/or individual renal issues such as: mucus casts in the urine, stones in the tubules, pain in the flanks, fluid retention in the lower body, bacterial infections in the kidneys, nephritis from medication sensitivities, and wasting of electrolytes like potassium (4). Some of these issues may be specific to particular CF management strategies, such as antibiotics-and may not occur in all people treated with those approaches (5).
My symptoms get worse if I drink too much liquid or my electrolyte levels drop. This creates a horrible vicious cycle, because low electrolyte levels often make people very thirsty. Increased thirst leads to higher fluid consumption and thus more electrolyte wasting (6).
I should mention that lack of medical knowledge has never been a barrier for me. I grew up in my parents' neuroscience lab at a medical school, earned multiple advanced degrees in health disciplines, and eventually became a medical educator myself. Despite these advantages, I have found managing CFKD frustrating.
As I have worked with my clinicians to recover from inadequate management of my CF during childhood and adolescence, I have frequently heard similar statements from them. My current nephrologist noted that providers are now learning about management of CFKD largely from patients. This is a newer area of clinical practice because not long ago, people with CF rarely survived long enough to develop kidney disease (7). By consequence, things that kidney health practitioners who treat people with CF observe in their daily practice have not necessarily emerged yet in the research literature on CFKD. This piece thus offers implicit guidance for further study as well as explicit recommendations for direct clinical practice.
As a medical educator who has lived with CFKD for many years, I see value in sharing lessons I have learned. This article primarily reflects my own perspectives as a patient while also incorporating my background as an interdisciplinary sociomedical scientist. It uses input from a small group of clinicians and evidence from the research literature as context for my own voice as a person aging with CFKD. The article thus includes elements of both case study and critical review, but should be viewed principally as a perspectives piece that centers opportunities in both research and practice. Here are my top 10 tips for kidney providers working with adult CF patients: 1. Talk (12). Ask about tolerance of supplements and any trouble swallowing them. Help me find the least problematic options for electrolyte maintenance. 6. Provide me with specimen cups. This allows me to catch my urine any time I suspect an infection (13). Keep me supplied with lab orders so I can get samples cultured promptly. Make sure I know the time window within which samples must be processed after collection. Having urine declined at the lab is frustrating. 7. Check in about my blood glucose levels. The fact that I do not currently have CF related diabetes does not mean that I never will. Some CF patients without clinical diabetes have other issues with blood sugar management (14). Monitor me for any potential kidney impacts from blood sugar issues, not just diabetes. 8. Find out how much water I am drinking. People with CFKD have to drink enough liquid to physically thin our mucus and flush out hardened casts from the tubules (4). However, we must also exercise caution not to drink so much that we stress our kidneys (15) or exacerbate any existing electrolyte imbalances (12 Finally, a general suggestion for both seasoned nephrology providers and those who are just starting out. Reading literature and talking to colleagues are always great ways to learn about best practices in kidney care for people aging with CF. However, there will be times when the right strategy still seems unclear. At those times, the absolute best thing to do is ask the patient! Adults with CF are usually accustomed to advocating for ourselves and quite knowledgeable about our bodies (18). Take advantage of that whenever you can.

AUTHOR CONTRIBUTIONS
The author confirms being the sole contributor of this work and approved it for publication.