Kidney stones, medically known as renal calculi, are hard deposits of minerals and salts that form within the kidneys. They vary in size and often cause severe pain as they travel through the urinary tract. Understanding the signs of stone passage is important for managing this painful experience and knowing next steps for your health.
Physical Indicators of Passage
The most significant indicator that a kidney stone has passed is often a sudden and dramatic reduction in the intense, wave-like pain, known as renal colic, that characterizes its movement. While some residual soreness or a dull ache might linger for a short period, the acute, severe discomfort subsides once the stone exits the body. This relief signifies that the obstruction in the urinary tract has cleared.
Observing the stone itself provides definitive confirmation of passage. You can attempt to catch the stone by urinating through a fine-mesh strainer or coffee filter. Kidney stones can appear small, gritty, or even jagged, with colors varying from yellow or brown to darker shades like black, or occasionally white, depending on their mineral composition.
Immediately following passage, you might notice temporary changes in urination, such as increased frequency or a sensation of relief. Blood in the urine, or hematuria, is a common symptom experienced throughout the stone’s journey, often causing the urine to appear pink, red, or brown. This visible blood subsides shortly after the stone passes, though it can persist briefly.
When You Don’t See the Stone
It is common for individuals to experience significant pain relief without ever visually confirming the passage of a kidney stone. Very small stones, under 4 millimeters, can pass through the urinary system with minimal or no noticeable symptoms, making them easy to miss even with careful straining.
Additionally, some kidney stones, particularly uric acid stones, may partially dissolve or break down into very fine, unidentifiable particles before passing. In these instances, the primary indicator of passage remains the substantial alleviation of pain. If your severe symptoms resolve, it strongly suggests the stone has moved, even if you do not see it.
What to Do After It Passes
After you suspect a kidney stone has passed, contacting your healthcare provider is an important next step. Informing them about the suspected passage allows them to update your medical record and provide further guidance. If you successfully collected the stone, keep it clean and dry in a secure container, such as a cup with a lid or a plastic bag, and bring it to your doctor’s office or a laboratory for analysis.
Analyzing the stone’s chemical makeup is important because it helps identify the specific type, such as calcium oxalate or uric acid. This information helps determine the underlying causes of stone formation and develop tailored prevention strategies to reduce future risk. Your doctor may also recommend follow-up imaging tests, such as an ultrasound, X-ray, or CT scan, within a few weeks or months. These scans confirm complete passage, ensure no residual fragments remain, and rule out any potential obstruction or damage to the urinary tract.
Urgent Medical Attention
While the passage of a kidney stone often brings relief, certain symptoms warrant immediate medical attention. If severe pain returns or worsens after initial relief, especially if accompanied by a fever higher than 101.5 degrees Fahrenheit, chills, or signs of infection such as cloudy or foul-smelling urine, you should seek emergency care. These symptoms could indicate a new stone, a persistent obstruction, or a serious urinary tract infection that requires prompt treatment.
An inability to urinate, even with a strong urge, is an emergency sign that could signal a complete blockage of the urinary tract. Persistent nausea and vomiting that prevents fluid intake also requires urgent care, as it can lead to dehydration and further complications. Prompt evaluation and intervention are important in these scenarios to prevent kidney damage or other severe health issues.