Differential Diagnosis for Elevated Serum Creatinine
Elevated serum creatinine is a common laboratory finding that can be caused by various conditions. Here's a differential diagnosis organized into categories:
- Single Most Likely Diagnosis
- Dehydration: This is often the most common cause of elevated serum creatinine, as it reduces blood volume and consequently renal blood flow, leading to a decrease in glomerular filtration rate (GFR).
- Other Likely Diagnoses
- Acute Kidney Injury (AKI): Conditions such as sepsis, shock, or nephrotoxic medications can cause AKI, leading to elevated serum creatinine.
- Chronic Kidney Disease (CKD): CKD is a progressive condition that can cause a gradual increase in serum creatinine over time.
- Nephrotic Syndrome: This condition is characterized by heavy proteinuria, hypoalbuminemia, and edema, which can lead to elevated serum creatinine.
- Medication-induced nephrotoxicity: Certain medications, such as NSAIDs, aminoglycosides, and contrast agents, can cause nephrotoxicity and elevate serum creatinine.
- Do Not Miss Diagnoses
- Rhabdomyolysis: This condition, characterized by muscle breakdown, can release myoglobin into the bloodstream, leading to acute kidney injury and elevated serum creatinine.
- Urinary tract obstruction: Obstruction of the urinary tract, such as kidney stones or bladder outlet obstruction, can cause a rapid increase in serum creatinine.
- Vasculitis: Conditions such as ANCA-associated vasculitis or lupus nephritis can cause inflammation of the blood vessels and kidneys, leading to elevated serum creatinine.
- Rare Diagnoses
- Myeloma kidney: This condition, associated with multiple myeloma, can cause cast nephropathy and elevate serum creatinine.
- Sarcoidosis: This autoimmune condition can cause granulomatous inflammation in the kidneys, leading to elevated serum creatinine.
- Amyloidosis: This condition, characterized by the deposition of abnormal proteins in the kidneys, can cause nephrotic syndrome and elevated serum creatinine.
- Lead nephropathy: Chronic lead exposure can cause kidney damage and elevate serum creatinine.
Each of these diagnoses has a unique set of clinical and laboratory features that can help guide the diagnostic workup and management of elevated serum creatinine.