What questions should be asked to a patient with a history of possible Acute Kidney Injury (AKI), presenting with dark urine and nausea?

From the Guidelines

When evaluating a patient with possible acute kidney injury (AKI) who reports dark urine and nausea, I recommend asking questions that cover recent exposures, medication history, symptoms, and medical background to promptly identify the likely cause of AKI and guide immediate management decisions.

Key Questions to Ask

• Timing of symptom onset, specifically when they first noticed dark urine and nausea
• Urine volume (oliguria or anuria), associated symptoms like fever, flank pain, edema, or changes in mental status
• Recent medication use, particularly NSAIDs, antibiotics (especially aminoglycosides, vancomycin), ACE inhibitors, ARBs, diuretics, and contrast agents 1
• Recent illnesses, dehydration episodes, or trauma
• Pre-existing conditions like hypertension, diabetes, heart failure, or previous kidney disease
• Recent procedures involving contrast agents or surgeries
• Family history of kidney disease, recent travel, occupational exposures to nephrotoxins, and recreational drug use

Rationale

The combination of dark urine and nausea specifically raises concern for intrinsic causes like acute tubular necrosis, glomerulonephritis, or rhabdomyolysis, making these targeted questions essential for prompt diagnosis and treatment 1.

Considerations

According to the acr appropriateness criteria® renal failure study published in the Journal of the American College of Radiology in 2021, AKI is defined as an increase in creatinine by 0.3 mg/dL within 48 hours or an increase in serum creatinine to 1.5 times baseline (within prior 7 days) or urine volume 0.5 mL/kg/hr for 6 hours 1. Given the high incidence of AKI and its significant impact on patient morbidity and mortality, it is crucial to identify the specific cause of AKI to guide appropriate intervention 1. Evaluation of the patient with AKI includes a thorough history, physical examination, and laboratory analysis of blood and urine, and renal biopsy may be indicated for differentiation of nephritic and nephrotic syndromes 1. By asking the right questions, healthcare providers can quickly identify the likely cause of AKI and initiate prompt treatment to improve patient outcomes.

From the Research

Patient Assessment

To assess a patient with a history of possible Acute Kidney Injury (AKI) presenting with dark urine and nausea, the following questions should be asked:

• What is the patient's medical history, including any previous episodes of AKI or kidney disease? 2, 3
• What are the patient's current symptoms, including the duration and severity of dark urine and nausea? 2, 3
• What medications is the patient currently taking, including any that may be nephrotoxic? 2, 4
• Has the patient recently undergone any medical procedures, such as contrast imaging studies? 2
• What is the patient's volume status, including any signs of dehydration or fluid overload? 5

Etiology and Classification

To determine the underlying cause of AKI, the following questions should be asked:

• Is the AKI prerenal, intrinsic renal, or postrenal in nature? 2, 3, 6
• Are there any signs of decreased renal perfusion, such as hypotension or dehydration? 2, 5
• Are there any signs of intrinsic renal damage, such as hematuria or proteinuria? 4, 6
• Are there any signs of postrenal obstruction, such as flank pain or difficulty urinating? 2, 3

Diagnostic Evaluation

To evaluate the patient's kidney function and determine the severity of AKI, the following questions should be asked:

• What are the patient's serum creatinine and urine output levels? 2, 3, 4
• Are there any other laboratory abnormalities, such as electrolyte imbalances or acid-base disturbances? 4, 5
• Are there any imaging studies, such as renal ultrasound or CT scan, that may be helpful in evaluating the patient's kidney function? 2, 5