Snapshot A 54-year-old man presents to his primary care physician with chest pain. His chest pain began approximately 2 weeks ago and worsens when taking deep breaths. He reports that sitting up and leaning forward improves his symptoms and that his chest pain is not associated with exertion. He says that his symptoms are associated with mild shortness of breath and fatigue. Medical history is significant for type 2 diabetes mellitus, hyperlipidemia, and hypertension. He has been non-adherent to his medications. Social history is notable for smoking 1 pack of cigarettes per day for 20 years. Vital signs are significant for a blood pressure of 163/112 mmHg. On physical examination, there is a pericardial friction rub and peripheral edema. On laboratory testing, his glomerular filtration rate (GFR) 48 mL/minute/1.73 m2. Introduction Clinical definition chronic kidney disease (CKD) describes abnormalities in kidney structure or function occuring for > 3 months e.g., glomerular filtration rate (GFR) < 60 mL/minute/1.73 m2 for > 3 months when CKD requires renal transplantation or dialysis, the patient is said to have end-stage renal disease (ESRD) Epidemiology incidence 1 in 10 American adults have some form of CKD risk factors older age diabetes mellitus hypertension acute kidney injury microalbuminuria or proteinuria overweight or obesity smoking, alcohol, and drug abuse Etiology insults that result in renal damage e.g., diabetes mellitus, autoimmune disease (such as lupus), and hypertension Pathogenesis in normal conditions the kidneys have the ability to maintain glomerular filtration rate (GFR) in the setting of nephron loss this is accomplished by hyperfiltration and hypertrophy of the remaining nephrons when GFR decreases to 50% there will be an increase plasma substances such as creatinine and urea a number of sequela occur as the GFR continues to decrease such as hyperkalemia metabolic acidosis normochromic normocytic anemia secondary to decreased synthesis of erythropoietin secondary hyperparathyroidism hyperphosphatemia hypocalcemia secondary to decreased hydroxylation of 25-hydroxyvitamin D to calcitriol impairment of sodium and free water excretion this results in extracellular fluid (ECF) expansion and total-body volume overload this leads to peripheral and pulmonary edema and hypertension Prognosis typically progressive loss of renal function and may result in ESRD Presentation Symptoms typically asymptomatic in early stages of the disease clinical presentation secondary to uremia include fatigue nausea and vomiting pruritis chest pain secondary to pericarditis or pleuritis seizure Physical exam hypertension uremic frost growth retardation in children peripheral edema osteitis fibrosa cystica osteomalacia "renal rickets" Imaging Renal ultrasound indication considered the first-line imaging modality when working up a patient with CKD used to evaluate between obstructive and intrinsic parenchymal disease to assess for retroperitoneal involvement and renal cysts Studies Labs complete blood count (CBC) can see normochromic, normocytic anemia basic metabolic panel ↑ blood urea nitrogen (BUN), creatinine, and potassium ↑ phosphate ↑ parathyroid hormone ↓ calcium ↓ calcitriol cystatin C it is secreted but not reabsorbed an endogenous marker of renal function urine studies to assess for proteinuria can see waxy-casts on urinalysis in patients with ESRD and CKD Biopsy percutaneous renal biopsy is typically performed when there is renal impairment (or nephrotic range proteinuria) and the diagnosis is unclear after extensive workup Differential Acute on chronic kidney disease Treatment Conservative protein restriction indication a method of managing dietary protein that may reduce the rate of renal decline Medical ACE inhibitors or ARBs indications considered first-line for strict blood pressure control blood pressure goal of < 130/80 mmHg blood pressure control can help delay worsening of CKD to manage proteinuria in patients with diabetic kidney disease vitamin D supplementation indication for prevention and treatment of secondary hyperparathyroidism erythropoiesis-stimulating agent indication can be considered to manage anemia in patients with CKD hemoglobin goal is 10-12 g/dL phosphate binders indication to treat hyperphosphatemia in patients with CKD statins indication used as cholesterol lowering therapy in patients with CKD dialysis indication in patients with severe metabolic acidosis, hyperkalemia, pericarditis, intractable volume overload, and encephalopathy Operative renal transplant indication a treatment option for patients with CKD Complications Anemia Mineral and bone disease Hypertension Hypervolemia Depression Cardiovascular disease