Trimethoprim-sulfamethoxazole induced acute interstitial nephritis in renal allografts; clinical course and outcome.
BACKGROUND
Acute interstitial nephritis (AIN) secondary to trimethoprim-sulfamethoxazole (TMP-SMX) is well documented as a cause of acute renal failure in native kidneys. TMP-SMX is the standard prophylactic agent against pneumocystis carinii (PCP) used in the early post-transplant period, however, it has to date only been indirectly associated with AIN in renal allografts.


METHODS
We describe eleven renal transplant patients with acute allograft dysfunction in whom a transplant biopsy demonstrated primary histopathologic features of allergic AIN, all of whom were receiving TMP-SMX in addition to other medications known to cause AIN.


RESULTS
All cases occurred within 1 month of transplantation and accounted for 2.12% (11/518) of the total number of transplant biopsies performed during the study period. However, this figure increased to 10.1% (11/109) when those biopsies performed for early allograft dysfunction (< 1 month) were taken into account. After discontinuation of TMP- SMX alone, all patients had an immediate improvement in serum creatinine with excellent long term allograft function - mean improvement of serum creatinine from 465 micromol/l to 136 micromol/l at last follow-up (range 15 - 55 months).


CONCLUSIONS
AIN secondary to TMP-SMX, although an uncommon cause of allograft dysfunction over the study period, accounted for over 10% of cases of allograft dysfunction within the first month of transplantation. Therefore, a high degree of clinical suspicion for TMP-SMX-induced AIN is warranted when confronted with early acute allograft dysfunction.
Department of Nephrology, Beaumont Hospital, Dublin, Ireland.
J P
JP
Garvey
C M
CM
Brown
S H
SH
Chotirmall
A M
AM
Dorman
P J
PJ
Conlon
J J
JJ
Walshe
D000208:Acute Disease; D000328:Adult; D000368:Aged; D000890:Anti-Infective Agents / Q000009:adverse effects* / Q000627:therapeutic use; D003404:Creatinine / Q000097:blood; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D007668:Kidney / Q000473:pathology / Q000503:physiopathology; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D009395:Nephritis, Interstitial / Q000139:chemically induced* / Q000175:diagnosis / Q000473:pathology; D015662:Trimethoprim, Sulfamethoxazole Drug Combination / Q000009:adverse effects* / Q000627:therapeutic use
D000890:Anti-Infective Agents; D007166:Immunosuppressive Agents; D015662:Trimethoprim, Sulfamethoxazole Drug Combination; D003404:Creatinine