Valor crítico da citrulina para as complicações do enxerto no transplante de intestino / Critical value of citrulline for complications of intestinal transplant graft

OBJETIVO: Analisar, numa ampla amostra, o valor crítico da citrulina que confirma a presença das principais complicações do enxerto: rejeição e infecção. MÉTODOS: Foram coletadas 2135 amostras de citrulina sérica, na forma de gota de sangue seca, de 57 doentes submetidos a transplante de intestino/multivisceral no Jackson Memorial Hospital na Universidade de Miami, de março de 2004 a abril de 2006. Todas as amostras são do pós-operatório três meses em diante, passada a conhecida curva de elevação da citrulina após a recuperação das lesões causadas pela isquemia e reperfusão do pós-transplante. RESULTADOS: Utilizando um valor limite menor que 13 µmoles/L, a sensibilidade da citrulina foi de 96,4 por cento para detectar rejeicão celular aguda (RCA) moderada ou grave. A especificidade para as complicações mais freqüentes, rejeição e infecção foi de 54 por cento-74 por cento nas crianças e 83 por cento-88 por cento nos adultos, e o valor preditivo negativo (VPN) foi > 99 por cento. CONCLUSÃO: A citrulina pode ser utilizada como método não-invasivo para avaliar a evolução do enxerto intestinal após três meses do TI. Os episódios de RCA moderado e grave podem ser afastados quando o valor da citrulina for maior que 13 µmoles/L devido ao alto valor preditivo negativo.

OBJECITIVE: A biochemical marker for detection of acute cellular rejection following small intestine transplantation has been sought. Citrulline, a non- protein amino acid synthesized mainly by functioning enterocytes, has been proposed. Trial sensitivity has been reportedly high but with low specificity. Thus, the goal was to determine, in a sufficiently large analysis, the significant value of citrulline level in the post-transplant setting, which would correlate with complications such as rejection and infection. METHODS: Since March, 2004 2,135 dried blood spot (DBS) citrulline samples were obtained from 57 small intestine transplant recipients three months or more after post-transplant, i.e., once the expected period of recovery in the citrulline levels had occurred. RESULTS: Using a <13 vs. > 13 µmoles/L cut off point, sensitivity of DBS citrulline for the detection of moderate or severe ACR was extremely high (96.4 percent). Furthermore, specificity estimates (given the absence of ACR and these particular infections), while controlling for time-to-DBS sample were reasonably high (54 percent-74 percent in children and 83 percent-88 percent in adults), and the negative predictive value (NPV) was >99 percent. CONCLUSION: Citrulline is a non-invasive marker to evaluate problems of the intestinal graft after three months post-transplant. Due to the high NPV, a moderate or severe ACR can be ruled out, based exclusively on knowledge of a high value for DBS citrulline.

Intestinal Graft-Versus-Host Disease after Bone Marrow Transplantation: 7 Cases Proven by Histopathologic Diagnosis / 대한소화기내시경학회지

Graft-versus-host disease (GVHD) is the major cause of morbidity or mortality after marrow transplantation. The intestinal involvement of GVHD is associated with high graft failure. It is usually difficult to diagnose gastrointestinal (GI) GVHD because symptom is nonspecific, and diagnostic criteria in endoscopic and histologic findings lack the gold standard. We reviewed 7 patients with GI GVHD proven by endoscopic biopsy from September 1999 to June 2003. The common GI symptoms at the time of endoscopy were diarrhea and abdominal pain. Four patients were acute GVHD, two acute and chronic GVHD, and one chronic GVHD. The interval from bone marrow transplantation to GVHD diagnosis by histological examination varied from 18 days to 259 days. The skin was involved in 5 patients. Two cases showed normal endoscopic finding. From these results, endoscopic biopsy is a essential tool in evaluating patients with GI complaints after bone marrow transplantation.