A 40-year-old woman is referred for evaluation of chronic kidney disease (CKD). She has a two-year history of intermittent back, bilateral flank, and central abdominal pain. She has lost approximately 15 lbs (6.8 kg) and is easily fatigued. She had an episode of deep venous thrombosis one year ago that has not recurred. She has noticed mild bilateral pedal edema. She works in an office and denies using tobacco or illicit drugs. Up until two years ago, she felt well and is unaware of any chronic medical problems. Her current medications include over-the-counter acetaminophen and ibuprofen for pain control.
Her examination is unremarkable except for diffuse mild abdominal tenderness and bilateral, 2+, brawny lower extremity edema.
Laboratory results are as follows:

On renal ultrasound, both kidneys measure 12.5 cm (normal 9-12 cm). There is bilateral clubbing and mild-to-moderate dilation of the calices without dilation of the mid or distal ureters.
Which of the following is the most likely diagnosis?

Question

A 40-year-old woman is referred for evaluation of chronic kidney disease (CKD).  She has a two-year history of intermittent back, bilateral flank, and central abdominal pain.  She has lost approximately 15 lbs (6.8 kg) and is easily fatigued.  She had an episode of deep venous thrombosis one year ago that has not recurred.  She has noticed mild bilateral pedal edema.  She works in an office and denies using tobacco or illicit drugs.  Up until two years ago, she felt well and is unaware of any chronic medical problems.  Her current medications include over-the-counter acetaminophen and ibuprofen for pain control.
Her examination is unremarkable except for diffuse mild abdominal tenderness and bilateral, 2+, brawny lower extremity edema.
Laboratory results are as follows:

On renal ultrasound, both kidneys measure 12.5 cm (normal 9-12 cm).  There is bilateral clubbing and mild-to-moderate dilation of the calices without dilation of the mid or distal ureters.
Which of the following is the most likely diagnosis?

Quizplus · Accepted Answer

11ec193a_9902_87ce_853d_49b7c704465f_MD0002_00 This patient's presentation is most consistent with retroperitoneal fibrosis, a rare disorder causing mid and distal ureteral obstruction without the usual ureteric dilation seen in obstructive uropathy. Retroperitoneal fibrosis is usually idiopathic, but it has been associated with drugs (e.g., beta blockers, bromocriptine, ergots), malignancy (e.g., lymphoma), infections (e.g., TB), and radiation therapy. Retroperitoneal fibrosis is the result of chronic inflammation with fibroblast proliferation, leading to chronic periaortitis and involvement of surrounding structures. Patients typically present with pain that is dull, noncolicky, and occurring in a girdle distribution. Abdominal CT is preferred along with biopsy when clinically indicated. Treatment involves steroids, relieving ureteral obstruction (e.g., percutaneous nephrostomy tube or surgery), and treating the underlying disorder. This patient has many findings of retroperitoneal fibrosis, including history of long-standing abdominal pain, weight loss, previous DVT (likely due to venous obstruction), lymphedema, typical ultrasound findings, renal failure with bland urinary sediment, and elevated ESR and CRP. (Choice A) Advanced cervical cancer usually spreads into the broad ligament and causes obstruction of one or both ureters with significant ureteric dilation, which is not consistent with this patient's findings. (Choice B) Chronic glomerulonephritis usually presents with proteinuria, which is not present in this patient. (Choice C) Chronic interstitial nephritis usually presents with casts and more active urinary sediment (e.g., WBCs, RBCs), but it does not cause caliceal clubbing. (Choice D) Renal tuberculosis typically presents as a combination of upper and lower genitourinary tract disease with hematuria, sterile pyuria, ureteric strictures, contracted bladder; and calcification of the vas deferens, seminal vesicles, or prostate. Educational objective: Retroperitoneal fibrosis typically presents with nonspecific pain in the low back, flank, or abdomen. Patients usually have progressively worsening periaortic fibrosis that leads to kidney injury, ureteral obstruction without ureteral dilation, and possible IVC obstruction with edema and DVT. Treatment involves steroids, relieving the obstruction, and treating the underlying cause. __________ References: Idiopathic retroperitoneal fibrosis: prospective evaluation of incidence and clinic-radiologic presentation. (http://www.ncbi.nlm.nih.gov/pubmed/19593223) Obstructive nephropathy as a result or retroperitoneal fibrosis: a review of its pathogenesis and associations. (http://www.ncbi.nlm.nih.gov/pubmed/10495799)

A 40-Year-Old Woman Is Referred for Evaluation of Chronic Kidney