Differential Diagnosis
- The patient's presentation with malaise, nausea, anorexia, lethargy, and elevated creatinine level after recent chemotherapy for high-grade lymphoma is concerning for several potential diagnoses.
Single Most Likely Diagnosis
- Tumor Lysis Syndrome (TLS): This condition is a life-threatening metabolic disorder that occurs when a large number of cancer cells die rapidly, releasing their contents into the bloodstream. Given the patient's recent chemotherapy session and high-grade lymphoma diagnosis, TLS is a highly likely cause of his acute kidney injury (indicated by the elevated creatinine level). TLS can lead to elevated uric acid, phosphorus, and potassium levels, which can cause renal failure.
Other Likely Diagnoses
- Nephrotoxicity from Chemotherapy: Certain chemancer agents are known to be nephrotoxic and can cause acute kidney injury. Given the patient's recent chemotherapy, this is a plausible cause of his elevated creatinine level.
- Dehydration: Patients undergoing chemotherapy often experience nausea, vomiting, and diarrhea, leading to dehydration. Dehydration can cause a prerenal acute kidney injury, which would explain the elevated creatinine level.
- Sepsis: Patients with cancer, especially those undergoing chemotherapy, are at increased risk of developing infections. Sepsis can cause acute kidney injury and would explain the patient's malaise, nausea, and lethargy.
Do Not Miss Diagnoses
- Hemorrhagic Cystitis: This is a potentially life-threatening condition caused by certain chemotherapy agents, such as cyclophosphancer and ifosficer. It can cause renal failure and would be a critical diagnosis to miss.
- Obstruction of the Urinary Tract: Although less likely, an obstruction of the urinary tract (e.g., kidney stones, tumor obstruction) can cause acute kidney injury and would be a critical diagnosis to miss.
Rare Diagnoses
- Thrombotic Microangiopathy (TMA): This is a rare condition characterized by the presence of microthrombi in small blood vessels, which can cause renal failure. Certain chemotherapy agents and cancer types can increase the risk of TMA.
- Membranous Nephropathy: This is a rare autoimmune condition that can cause renal failure. Although unlikely, it could be a consideration in this patient, especially if other causes are ruled out.