Acute kidney injury on top of chronic kidney disease

It may be reversible, but reduced kidney reserve makes early identification of the trigger especially important.

Chronic kidney disease develops over time, while acute kidney injury is a rapid change over hours or days. Common triggers include dehydration from vomiting or diarrhoea, a severe infection, low blood pressure, urinary blockage, and medicines that affect kidney blood flow or fluid balance. Blood tests showing rising creatinine and changes in urine output help clinicians recognise the acute change.

The condition may cause little warning at first. Possible features include passing less urine, swelling, nausea, unusual drowsiness, breathlessness or worsening fatigue. These features can also have other causes, so assessment relies on examination, blood and urine tests, and sometimes imaging.

Contact a clinician promptly if you have chronic kidney disease and become acutely unwell, especially after fluid loss, fever, difficulty passing urine or a recent medicine change. Bring a current medicines list and describe your usual urine pattern, recent intake and any vomiting or diarrhoea.

Do not try to correct the problem by forcing large amounts of fluid, because this may be unsafe when the body is retaining fluid. Avoid starting non-prescribed anti-inflammatory painkillers. A clinician should decide whether any regular medicine needs temporary adjustment and treat the underlying cause.

Seek emergency care for severe breathlessness, chest pain, new confusion, fainting, marked drowsiness, inability to pass urine, rapidly increasing swelling, or persistent vomiting that prevents drinking. These signs can reflect dangerous fluid, salt or waste-product changes and should not wait for a routine appointment.

Ask what likely triggered the acute change, how your current blood results compare with your usual kidney function, whether imaging is needed, which medicines are safe during the illness, and when blood and urine tests should be repeated. Also ask for clear instructions about fluid intake and the symptoms that should trigger emergency care.