Acute Kidney Injury (AKI)

Acute kidney injury (AKI) is a sudden decline in kidney function that develops over hours to days. It is commonly triggered by dehydration, severe infection (sepsis), certain medications, contrast dye used in imaging, or blockage of urine flow. Although AKI can be a serious condition, it is often reversible when identified early and treated promptly.

At The Medical Group of New Jersey, our nephrologists evaluate AKI quickly, determine the underlying cause, and initiate targeted treatment to protect kidney function and prevent long-term complications.

Symptom Onset & Initial Evaluation

AKI may cause no or few noticeable symptoms in the early stages and is often first detected through abnormal blood or urine tests. When symptoms do appear, they may include:

• Decreased urine output or dark-colored urine
• Swelling of the legs, ankles, or around the eyes
• Fatigue, confusion, or shortness of breath
• Nausea, vomiting, or loss of appetite

During your initial evaluation at The Medical Group of New Jersey, your nephrologist will:

• Review recent illnesses, medications (including NSAIDs, antibiotics, and contrast agents), and any fluid losses such as vomiting or diarrhea.
• Ask about urinary symptoms, flank pain, and any difficulty emptying the bladder.
• Perform a physical exam to assess hydration status, blood pressure, and signs of infection or urinary obstruction.
• Coordinate urgently with Hospital Medicine or Emergency Medicine if your condition requires immediate intervention.

Diagnosis & Risk Assessment

AKI is diagnosed based on rising serum creatinine levels and/or reduced urine output over a short period of time. To identify the cause and determine severity, your nephrologist may order:

• Basic metabolic panel: Assesses creatinine, BUN, electrolytes, and acid–base balance.
• Urinalysis and urine microscopy: Look for blood, protein, crystals, or casts.
• Urine electrolytes and fractional excretion tests: Help distinguish pre-renal, intrinsic, and post-renal causes.
• Renal ultrasound: Evaluates kidney size and checks for obstruction.
• Additional imaging or laboratory studies: Used when sepsis, rhabdomyolysis, toxins, or other systemic illnesses are suspected.

These findings help classify AKI as pre-renal, intrinsic (such as acute tubular necrosis or glomerulonephritis), or post-renal (obstructive), which directly guides the treatment approach.

Treatment & Management

Treatment focuses on correcting the underlying cause and supporting kidney recovery. Depending on the diagnosis, your care plan may include:

• Fluid resuscitation to restore circulation in dehydration or low blood pressure
• Stopping or adjusting nephrotoxic medications, including NSAIDs, certain antibiotics, and contrast dye
• Treating infections with appropriate antibiotics
• Relieving urinary obstruction, using catheter placement, stenting, or other urologic procedures
• Managing electrolyte abnormalities, especially potassium, to prevent dangerous arrhythmias

In severe cases where kidney function declines significantly, temporary dialysis may be necessary to remove toxins, manage fluid overload, and stabilize electrolytes while the kidneys heal.

Monitoring & Follow-Up

Your nephrologist will continue to monitor your recovery closely. Follow-up includes:

• Regular laboratory testing (creatinine, BUN, electrolytes, bicarbonate) during the acute phase—sometimes daily or several times per week
• Tracking urine output and overall fluid status
• Adjusting medications as kidney function returns to baseline
• Scheduling outpatient follow-up visits to ensure full or near-full recovery and to screen for residual Chronic Kidney Disease

Prognosis & Preventive Care

Many patients recover fully from AKI, especially when treatment begins early. However, experiencing AKI increases the risk of developing future episodes and may raise the likelihood of chronic kidney disease over time.

To reduce the risk of recurrence, your nephrologist may recommend:

• Staying well hydrated during illness, heat exposure, or periods of increased physical activity
• Avoiding unnecessary NSAIDs and discussing high-risk medications with your nephrologist at The Medical Group of New Jersey
• Informing all healthcare providers of any prior AKI, especially before contrast imaging or elective surgery

With prompt treatment, close monitoring, and preventive strategies, patients can often restore kidney function and protect long-term kidney health.