That’s because symptoms tend to become apparent in the later stages of the disease, when it is most difficult to treat. Making matters worse, many of the symptoms that do ultimately appear are attributed to other conditions, per the NKF. That’s why it’s so crucial to know what to look for when it comes to renal disease. The sooner you spot symptoms, the sooner you can slow the progression of damage to your kidneys. Read on to find out which surprising kidney symptom may occur in your fingers, and why you should always tell a doctor if you notice it. RELATED: If You Drink This Beverage Often, Get Your Kidneys Checked, New Study Says. When your fingers become swollen, it typically means that your body is retaining fluid. One possible underlying cause is renal disease. According to the NKF, “the kidneys filter wastes from the blood and remove excess water from the body via urine. When the kidneys aren’t doing their job, this fluid can stay in the system instead of being excreted.” This can lead to swelling in the joints, a kidney symptom that the organization says “shouldn’t be dismissed.” Additionally, the NKF notes that “decreased kidney function can lead to sodium retention,” another cause for swelling. “Sodium accumulation is one of the consequences of renal failure, resulting in increased water intake, increases in the extracellular volume, and accompanying rise in blood pressure,” says a 2010 study on the matter.ae0fcc31ae342fd3a1346ebb1f342fcb RELATED: If You Notice This on Your Face, Have Your Kidneys Checked. While swelling in the fingers and hands is considered typical of late-stage renal disease, this same swelling is characteristic of heart disease, which the NKF notes often occurs simultaneously in patients. “If you have heart disease, it is likely that you have kidney disease and vice-versa. Many people don’t experience severe symptoms until their kidney or heart disease is quite advanced,” the organization writes. That’s why if you notice swelling, it may be linked to both causes at once—and you should speak with your doctor about both possibilities. “Swelling around the hands, feet, and ankles may be associated with kidney or heart failure,” write NKF experts. They add that kidney failure and heart failure often occur in tandem because “CKD [chronic kidney disease] is linked with high blood pressure, high cholesterol, and high blood sugar (diabetes), all of which can increase the risk of heart disease.” Symptoms of kidney disease typically only appear when the condition reaches an advanced stage, meaning it’s time to take immediate action if you believe you’re showing signs of kidney-related illness. According to the Mayo Clinic, those with chronic kidney disease may experience nausea, vomiting, loss of appetite, fatigue, changes in the frequency of urination, muscle cramps, dry or itchy skin, high blood pressure, shortness of breath, and chest pain. The NKF adds that you may also notice protein or blood in your urine, or your urine may appear foamy. If your swelling is accompanied by any of these symptoms, ask your doctor whether a kidney screening is right for you. For more health advice sent directly to your inbox, sign up for our daily newsletter. Though sudden swelling can be linked to chronic kidney disease or renal failure, it can also have a range of other underlying causes—many of them more benign. For instance, your swollen fingers may be the result of a salty meal causing sodium retention unrelated to a kidney condition, or your blood vessels reacting to heat, according to WebMD. These are both considered normal reactions, and should subside within hours. Swelling can also be the result of injury or infection, either of which may require medical attention. If symptoms persist over time, it could be something more serious, such as rheumatoid arthritis or lymphedema. Speak with your doctor to discuss the full range of possible underlying causes if your symptoms don’t resolve on their own. RELATED: If This Body Part Hurts You at Night, See Your Doctor.