Differential Diagnosis

The patient presents with an elevated creatinine level of 1.79, a GFR estimated at 36, sinus tachycardia, and nonspecific ST and T wave abnormalities on the EKG. Based on these findings, the differential diagnosis can be categorized as follows:

• Single Most Likely Diagnosis
  • Chronic Kidney Disease (CKD): The elevated creatinine level and decreased GFR strongly suggest CKD. The nonspecific EKG changes can be seen in various conditions, including electrolyte imbalances that are common in CKD.
• Other Likely Diagnoses
  • Dehydration: Can cause a rise in creatinine and lead to sinus tachycardia due to hypovolemia. Electrolyte imbalances from dehydration can also cause nonspecific EKG changes.
  • Electrolyte Imbalance: Abnormal levels of potassium, calcium, or magnesium can affect kidney function and cause EKG changes, including nonspecific ST and T wave abnormalities.
  • Cardiac Conditions: Such as coronary artery disease or cardiomyopathy, which can lead to sinus tachycardia and nonspecific EKG changes. Reduced kidney function can also be a consequence of heart failure.
• Do Not Miss Diagnoses
  • Acute Kidney Injury (AKI): Although the GFR suggests chronic disease, an acute component or exacerbation could be present, especially if there's a recent increase in creatinine. AKI can be caused by various factors, including medications, toxins, or severe dehydration.
  • Hyperkalemia: A life-threatening condition that can cause cardiac arrhythmias, including those seen on the EKG. It's a common complication of kidney disease.
  • Uremic Pericarditis: Inflammation of the pericardium due to uremia, which can cause chest pain and EKG changes. Although less common, it's a serious condition that requires prompt recognition.
• Rare Diagnoses
  • Amyloidosis: A condition where abnormal proteins (amyloid) accumulate in organs, potentially affecting both the kidneys and heart, leading to the observed symptoms and EKG changes.
  • Sarcoidosis: An inflammatory disease that can affect multiple organs, including the kidneys and heart, potentially causing the observed abnormalities.

Each of these diagnoses requires careful consideration of the patient's full clinical picture, including history, physical examination, and additional diagnostic tests as needed.