Kidney Function

There are many causes of late kidney transplant dysfunction. Common causes include chronic transplant injury resulting from rejection and nonimmunologic causes, such as hypertension, calcineurin-inhibitor nephrotoxicity, urinary obstruction, viral or bacterial infections, and, less commonly, recurrent disease. We present an interesting case in which the cause of late transplant dysfunction was identified on a transplant biopsy.

Ingestion of a very large amount of methanol usually causes serious toxicity. Methanol is metabolized by alcohol dehydrogenase in the liver to formaldehyde and then quickly transformed by aldehyde dehydrogenase to formic acid. Although methanol is directly responsible for the initial signs and symptoms of inebriation, formaldehyde and formate are responsible for the characteristic blindness and metabolic acidosis with a high plasma anion gap. Lactic acid accumulation also can occur through inhibition of mitochondrial cytochrome oxidase by formate.

Background: The role of smoking as a risk factor for adverse renal outcomes after kidney transplant has not been well studied. We therefore undertook this investigation to assess the association of smoking with transplant outcomes.Study Design: Retrospective cohort study.Setting & Participants: 997 consecutive laparoscopic live donor kidney transplant recipients at a tertiary-care transplant center.Predictor: Smoking at the time of the transplant evaluation.Outcomes & Measurements: Primary outcome is transplant survival.Results: At the time of pretransplant evaluation, 329 participants had ever smoked and 668 participants had never smoked. Transplant survival was worse in ever smokers compared with never smokers (adjusted HR, 1.47; 95% CI, 1.08-1.99; P = 0.01), as was patient survival (adjusted HR, 1.60; 95% CI, 1.06-2.41; P = 0.02). First-year rejection-free survival was substantially worse (adjusted HR, 1.46; 95% CI, 1.05-2.03; P = 0.03) and risk of rejection on or before posttransplant day 10 was much higher (adjusted HR, 1.8; 95% CI, 1.10-2.94; P = 0.02) in ever smokers compared with never smokers. Glomerular filtration rate (estimated using the Modification of Diet in Renal Disease Study equation) at 1 year posttransplant was lower and poor early transplant function was more common in ever smokers on univariate, but not multivariate, analysis.Limitations: Lack of quantitation of smoking exposure and uncertainty about whether patients were still smoking at the time of transplant.Conclusions: Our results suggest that any history of smoking before transplant is associated with impaired transplant and patient survival and increases the risk of early rejection after live donor kidney transplant. Further study is needed to determine whether smoking may impart immunomodulatory and perhaps nephrotoxic effects.