Differential Diagnosis for Patient with Midline to Right Lower Flank Pain
Single Most Likely Diagnosis
- Chronic Pain or Neuropathic Pain Post-Nephrectomy: The patient's history of right open nephrectomy 8 months ago and the persistence of similar pain since then, now worsening, suggests that the pain could be related to the surgical intervention. The development of chronic pain or neuropathic pain post-surgery is a recognized complication.
Other Likely Diagnoses
- Urinary Retention or Bladder Outlet Obstruction: Symptoms of polyuria, polydipsia, and dribbling could indicate issues with the bladder or urethra, such as obstruction or retention, which might be causing or contributing to the flank pain.
- Kidney Stone or Nephrolithiasis: Although the patient has had a nephrectomy, it's possible for stones to form in the remaining kidney or in the ureter, causing flank pain. The pain's location and radiation could suggest a stone, especially if it has moved or is causing obstruction.
- Pyelonephritis or Kidney Infection: An infection in the remaining kidney could cause flank pain, especially if it's severe or recurrent. The symptoms of polyuria and polydipsia might also be related to a urinary tract infection.
Do Not Miss Diagnoses
- Ureteral Stricture or Obstruction: This is a potential complication post-nephrectomy and could cause severe pain, urinary retention, and other urinary symptoms. Missing this diagnosis could lead to severe consequences, including loss of the remaining kidney function.
- Renal Cell Carcinoma in the Remaining Kidney: Although less likely, given the recent history of nephrectomy for presumably similar reasons, it's crucial not to miss a new or recurrent malignancy in the remaining kidney, which could present with flank pain and other systemic symptoms.
- Sepsis from Urinary Source: Sepsis arising from a urinary tract infection or obstruction is a life-threatening condition that must be promptly identified and treated.
Rare Diagnoses
- Amyloidosis: A rare condition that can cause chronic pain and renal issues, including proteinuria and renal failure. It might be considered if other diagnoses are ruled out and the patient has systemic symptoms.
- Retroperitoneal Fibrosis: A rare condition characterized by the proliferation of fibrous tissue in the retroperitoneum, which can encase and obstruct structures such as the ureters, leading to renal failure and severe pain.