CC: Lower extremity swelling for 2 months
HPI: 32 year-old male with no known past medical history who presents with a chief complaint of lower extremity swelling for 2 months. Patient reports that he noticed swelling in his feet approximately 2 months prior to admission that has gradually worsened in severity. He now reports swelling extending to mid thighs that interferes with ability to ambulate comfortably, prompting him to present for evaluation. The swelling is not painful and without overlying skin discoloration and is symmetric bilaterally; he also states that his swelling is not firm but pits with digital pressure. He notes mild periorbital swelling over the past 3 weeks though he reports no visual disturbances. On exam, patient has periorbital edema and pitting lower extremity edema to mid thigh but otherwise no other signficant findings. Labs are significant for renal injury, non-gap acidosis, hyperkalemia, normocytic anemia, and UA>300 protein. The urine protein/creatinine ratio is 13.84, high above the cut off for nephrotic range proteinuria. Urine anion gap is positive. For work up of nephrotic syndrome, tests of ANA, SPEP/UPEP, Hepatitis panel, HIV, RPR, C3/C4, and HgbA1c were sent. The only pertinent finding was a HgbA1c of 10.1. A renal biopsy was pursued after ultrasound showed kidneys to be around 12cm in length with no other specific findings. Biopsy demonstrated patient to have Kimmelstiel Wilson nodules which is consistent with Diabetic Nephropathy.
Morning Report Pearls:
Once you have nephrotic range proteinuria, remember the types of nephrotic syndromes. This will help organize how to evaluate for underlying etiologies. Some of these syndromes can be idiopathic but most have secondary causes.
Some basic screenings should be done based off this information: HIV, HgbA1c, ANA, C3/C4, Hepatitis B/C, SPEP/UPEP with Light chains
Be on the look out for complications related to Nephrotic Syndrome secondary to loss of albumin (drop in oncotic pressure) and other proteins:
This patient had a non gap acidosis for which the differential is narrow:
Given the hyperkalemia in the setting of lack of oliguria or insults with CKD, it was thought that patient had Type IV RTA. Here is a breakdown of the RTAs: