When Is an IgA Nephropathy Hematuria Flare an Emergency?

Seeing dark, cola- or tea-colored urine can be frightening. While a brief episode of visible blood in the urine during a cold is a known and often self-limiting pattern in IgA nephropathy, you cannot tell if your kidneys are being injured just by looking at the color of your urine ^[1]. Because visible bleeding can sometimes lead to sudden kidney injury, and because blood can also come from infections, kidney stones, or other causes, it is important to know the difference between a common flare pattern and signs of a medical emergency ^[2]. Always follow a clear plan with your care team to check your kidney function.

What Does a Common Flare Pattern Look Like?

A classic IgA nephropathy flare is called synpharyngitic hematuria, meaning visible blood in the urine that occurs at the same time as a throat or respiratory infection ^[3][4].

• Timing: The dark urine typically starts while you are actively sick with a cold, sore throat, or other infection ^[3].
• Duration: The visible blood usually lasts for a few days (often 1 to 7 days) and then gradually clears up as you recover from the infection ^[3][4].
• Symptoms: You may have typical symptoms of your cold or flu, but you should not have new severe symptoms related to your kidneys or severe pain when urinating.

Even after your urine looks normal again, microscopic amounts of blood may remain, which is why follow-up testing is necessary ^[3].

When to Seek Care: A Triage Guide

Because you cannot assess kidney injury visually, you need to know when to seek emergency care versus when to call your nephrologist for a same-day urgent appointment.

Call Emergency Services Now

Seek immediate emergency medical attention if you experience any of these life-threatening warning signs:

• Inability to urinate: Passing very little or no urine at all, or being unable to pass urine because of blood clots, is a major warning sign of a severe acute kidney injury (AKI) or blockage ^[2].
• Shortness of breath: This can be a sign of fluid buildup in your lungs ^[5].
• Coughing up blood: A very rare but life-threatening complication called pulmonary hemorrhage requires immediate emergency care ^[6].
• Severe high blood pressure with symptoms: An extremely high blood pressure reading accompanied by severe headache, confusion, fainting, or vision changes ^[7][5].
• Fever with severe systemic illness: High fever, severe weakness, confusion, or persistent vomiting ^[7].

Contact Nephrology or Urgent Care Today

Call your nephrologist for a same-day assessment (or go to urgent care if they are unavailable) if you have:

• New or worsening swelling (edema): Rapid fluid buildup in your legs, ankles, or face ^[7][5].
• Falling urine output: Noticeably less urine than your usual baseline ^[2].
• New visible blood: Any new, out-of-pattern episode, especially if it occurs without a cold, is accompanied by severe pain, or lasts longer than a week.
• Blood clots: While not always an emergency, clots can cause blockages and require urgent evaluation.

Follow Your Agreed Flare Plan

If you have a familiar, brief episode of dark urine during a cold without any of the warning signs above, you should still follow the personalized plan agreed upon with your doctor. This typically involves contacting their office to report the flare and scheduling necessary lab work ^[8][9][10].

What to Expect from Medical Testing

Your doctor will likely order blood and urine tests to see how your kidneys are handling the flare ^[8][9][10].

• Blood tests: These measure serum creatinine (a waste product used to calculate your eGFR, an estimate of your kidney’s filtering function) and electrolytes (salts in your blood) to check for acute kidney injury.
• Urine tests: A urinalysis with microscopy looks for specific types of damaged red blood cells (dysmorphic red cells) or red-cell casts that confirm the bleeding is coming from your kidney filters. Your doctor will also use a quantitative test (like a protein-to-creatinine ratio) to measure proteinuria (protein in your urine), a marker of kidney filter stress.

Managing Medications and Fluids at Home

During a flare, it is crucial to manage your medications safely:

• Do not stop or adjust medications on your own: Drugs like blood pressure medications (ACE inhibitors or ARBs), diuretics, or SGLT2 inhibitors may need adjustment during an illness (a “sick-day plan”), but only under your doctor’s explicit guidance.
• Avoid NSAIDs: Painkillers like ibuprofen or naproxen can further stress your kidneys and should be avoided unless specifically approved by your clinician.
• Fluid management: While staying hydrated is important during a cold, do not force yourself to drink excess fluids if you have swelling, a fluid restriction, or noticeably reduced urine output.

Having a proactive plan in place helps you act quickly and confidently, ensuring that any potential complication is caught and treated early.