Renal transplant

Presentations

• Transplant-related infection
• Medication side effects
• Rejection
• Graft-versus-host disease
• Post-operative complications

History

• Temperature increase or decrease from baseline – may signify rejection or infection
• Change in urine output – may significant rejection or acute dehydration
• Date of transplant – guides differential
• Rejection history
• Recent changes in immunosuppresion
• Chronic infections (CMV, EBV, HBV, HCV)
• Recent exposure to infections (varicella, TB, CMV)
• Complication with immunosuppression
• Recent travel or sick contacts
• Baseline creatinine, BP and immunosuppressive blood levels

Examination

• Volume status
• Periorbital oedema (GN)
• Retina (CMV/toxoplasmosis chorioretinitis; Listeria endophthalmitis)
• Sinuses (S. aureus, mucormycosis, invasive fungal disease)
• Mouth (Candida, HSV)
• Neck (Meningismus, retropharyngeal abscess)
• Lymphadenopathy (CMV, EBV, hepatitis, lymphoproliferative disorder)
• Lungs: CAP organisms + PJP, Aspergillus, TB, coccidioidomycosis, viral pneumonias
• CVS: Pericardial friction rub of uraemic pericarditis. New murmur

Examination

• Abdomen
  • Peritonitis without source is common. 
• Flank/suprapubic
  • UTI most common infection identified
• Graft
  • Inspect wound, palpate (tenderness suggests acute rejection, outflow obstruction or pyelonephritis) and auscultate (Bruit suggests renal artery stenosis, AV malformation or AV fistula)
• Perirectal abscess

Examination

• Access site infections
• Peripheral oedema (Recurrent GN, renal graft failure, nephrotic syndrome (native kidney/s), renal vein thrombosis, malnutrition, hypoalbuminaemai or heart failure
• Skin for cellulitis, endocarditis
• Mental status
  • Cyclosporine/tacrolimus neurotoxicity, steroid psychosis, HSV encephalitis, Listeria meningoencephalitis and cryptococcal meningitis

Infection by time

• <1mo (surgical bugs)
  • Resistant organisms: MRSA, VRE, Candida
  • Complications of surgery/hospitalisation: Aspiration, catheter infection, wound infection, anastomotic leaks, C. difficile
  • Colonisation of solid organ: Aspergillus, Pseudomonas, Klebsiella, Legionella
• 1-6mo (opportunistic)
  • On PJP and antiviral prophylaxis: Polyomavirus BK infection/nephropathy, C. difficile, HCV, adenovirus, influenza, Cryptococcus neoformans, M. TB
  • Without prophylaxis: Pneumonia, HSV, VZV, CMV, EBV, HBV, Listeria, Nocardia, Toxoplasma, Strongyloides, Leishmania, Trypanosoma cruzi
• >6mo (community-acquired infections +- opportunistic)
  • General: CAP, UTI, Aspergillus, Mucor, Nocardia
  • Late viral: CMV colitis/retinitis, HBV/HCV, HSV encephalitis, SARS, JC virus, skin cancer, lymphoma

Complications of renal transplant specifically

• Vascular: Renal artery stenosis, allograft infarction, AV fistulas, pseudoaneurysm, renal vein thrombosis
• Non-vascular: Ureteral obstruction, urine leak, periallograft haematomas/lymphocoeles/abscess, neoplasms, post-transplant lymphoproliferative disase
• Chronic renal dysfunction often occurs over time due to graft fibrosis and glomerulosclerosis
• Should discuss medication changes and imaging contrast decisions with transplant team prior to delivery
• Serum creatinine is the most valuable prognostic marker of graft function at all times
• Red cell casts and proteinuria may indicate recurrent or de novo glomerulonephritis
• Proteinuria may suggest rejection, drug toxicity, glomerular disease
• Obtain cyclosporine and tacrolimus levels for all patients on these

Imaging

• USS is best test for obstruction and helpful if suspected of having pyelonephritis, vascular complications, perinephric abscess, urine leak, wound infection or acute rejection

Graft dysfunction and failure

• Chronic dysfunction precedes the majority of graft failures
• Acute renal failure = 20% rise from baseline creatinine (vs. 50% rise in other patients)
• DDx
  • Mechanical: Ureteral obstruction, urine leak
  • Vascular: Renal artery stenosis, renal artery thrombosis, renal vein thrombosis
  • Glomerulonephritis
  • UTI
  • Interstitial nephritis (polyoma BK virus, CMV, HSV-1/2, adenovirus
  • Rejection: Hyperacute, acute or late (Mostly presents as HTN and reduced UO)
  • Recurrent pyelonephritis/reflux
  • Nephrotoxic agents
  • Non-compliance with medications or management of HTN/diabetes post-transplant
  • Chronic allograft nephropathy

Acute renal failure

• Difficult to differentiate immunosuppressive nephrotoxic ARF vs. infected allograft
  • Traditionally fever and graft tenderness suggested infection but this is rare nowadays
  • Elevated levels of cyclosporine or tacrolimus suggest nephrotoxic effects
  • Serum creatinine levels remain the most valuable prognostic indicator of graft function

Last Updated on October 9, 2020 by Andrew Crofton