August 23, 2011 by dailybolusoflr
Renal Dysfunction in Renal Transplant Patients
· The kidney is the most commonly transplanted organ in the US.
· The most common time for acute rejection is in the 1st 4 weeks after transplantation, but acute rejection can occur at any time. This diagnosis is made by renal biopsy.
· Evidence of renal dysfunction in post-transplant patients should always raise suspicion for rejection, but reversible causes should be sought and corrected.
· Evaluation in the ED should include:
o UA can help diagnose infection; red cell casts or protein can point to glomerulonephrosis or vasculitis
o Ultrasound should be performed to evaluate for renal artery or vein thrombosis or renal artery stenosis. It can also find hydronephrosis from obstruction.
o BUN/Creatinine- can point to hypovolemia or other pre-renal states. Although it is important to note that an elevated BUN/creatinine ratio can also be seen in acute rejection states and in nephrotoxic states (most commonly from cyclosporine and tacrolimus)
o History- focus on typical infection questions, new medications that could have decreased effectiveness of cyclosporine/tacrolimus/sirolimus levels (some common: rifampin, phenobarbital, phenytoin, nafcillin, octreotide, valproic acid, St. Johns Wart), new nephrotoxic drugs (some common: gentamicin, vancomycin, bactrim, cimetadine, ranitidine, ketoconazole), urine output, suspicion for dehydration
o Exam-focus on site of transplanted kidney (is it tender or enlarged; site infected in recent surgery?); do they appear systemically ill (any systemic infection can lead to renal dysfunction)
Ref: Roberts and Hedges 5th edition (chapter 118)