The C terminus of AvrXa10 can be replaced by the transcriptional activation domain of VP16 from the herpes simplex virus

The avirulence gene avrXa10 of Xanthomonas oryzae pv oryzae directs the elicitation of resistance in a gene-for-gene manner in rice lines carrying the resistance gene Xa10. We have localized a transcriptional activator domain in the C terminus of AvrXa10 by using amino acid replacement mutagenesis. One mutant, with replacements at three hydrophobic amino acid residues in the C-terminal domain, was defective for transcriptional activation in yeast and avirulence activity in rice. The activation domain from the herpes virus protein VP16 restored the ability of the bacteria expressing the hybrid protein to elicit a resistance reaction. Elicitation was specific for Xa10, and the reaction had the hallmarks of the response to AvrXa10. The results indicate that a domain with the properties of a transcriptional activator plays a critical role in AvrXa10 function. The results also indicate that the protein has the potential to interact with the plant transcriptional program, although a role for the domain in the stability or conformation of the protein in the plant cannot be excluded. In a broader sense, the transcriptional activation domain of avrXa10 may represent a prokaryotic version of the acidic transcriptional activation domain, which heretofore has been found exclusively in eukaryotes.

Laparoscopic versus open donor nephrectomy: comparing ureteral complications in the recipients and improving the laparoscopic technique

BACKGROUND

Laparoscopic live donor nephrectomy (LDN) is a recently developed procedure, the performance of which needs to be studied. Given the reported advantages in the donors, this study looks at graft outcome and ureteral complications in recipients of kidneys procured by open donor nephrectomy (ODN) versus LDN.

METHODS

The LDN recipients consisted of 193 patients since 3/27/96. A total of 168 ODN recipients from 1991 to 1998 served as controls. Immunosuppression protocols were similar for both groups.

RESULTS

Two-year graft survival for LDN and ODN was 98% and 96%, respectively. Two-year patient survival for LDN and ODN was 98% and 97%, respectively. The incidence of delayed graft function and mean serum creatinine at 3 and 12 months was similar in both groups. However, the number of ureteral complications that required operative repair was significantly higher for LDN recipients compared to ODN recipients, 7.7% (n=15) vs. 0.6% (n=1) respectively (P=0.03). Ureteral stenting was required in an additional 3.1% (n=6) of LDN and 2.4% (n=4) of ODN (P=NS). There was, however, a learning curve with time. For the first 130 LDN patients, a total of 20 ureteral complications were recorded, whereas only one occurred in the more recent 63 patients (P=0.03).

CONCLUSIONS

The higher ureteral complication rate in LDN recipients has improved over time as technical causes have been identified. We have noted significant improvement in ureteral viability by using the endogastrointestinal anastomosis instrument on the ureter and peri-ureteral tissue. LDN is therefore an excellent alternative to ODN. Identification of hazards unique to this technique is critical before its broader application.

Portopulmonary hypertension and the liver transplant candidate

The management of the liver transplant (OLT) candidate with portopulmonary hypertension (PPHTN) has dramatically changed in the past 3 years. Careful preoperative evaluation with functional characterization of right ventricular function plays a critical role. The pulmonary vascular response to epoprostenol infusion serves as a deciding factor for OLT candidacy. Careful perioperative attention to avoid right ventricular failure from acutely elevated pulmonary artery pressures or sudden increases in right ventricular preload is a key physiologic tenet of management. With increased surgical expertise, anesthetic sophistication, and availability of epoprostenol, PPHTN is no longer considered an absolute contraindication for OLT.

Laparoscopic living donor nephrectomy and multiple renal arteries

BACKGROUND

Laparoscopic donor nephrectomy (LDN) is a new technique. While the short-term recipient renal function is equivalent to that of the traditional open nephrectomy (ODN), long-term function and potential exclusion criteria, such as the presence of multiple renal arteries, are as yet unknown.

METHODS

Retrospective review of 124 consecutive LDN performed from March 1996 to September 1997 with 117 ODN as historical controls.

RESULTS

The 1-year actuarial graft and patient survival for LDN kidneys were 94% and 95%, respectively. These were not statistically different from that of the ODN controls. The presence of multiple renal arteries did not alter graft and patient survival or prevalence of immunologic events. The number of recipient ureteral complications in the LDN group was 11.2% compared with 3.4% in ODN (P < 0.01). Following correction for a learning curve with accompanying technical modifications, the prevalence of recipient ureteral complications has decreased to 7% in the last 94 patients (P = nonsignificant versus ODN).

CONCLUSIONS

LDN represents a viable alternative to ODN for living renal transplants. Advantages for the donor are matched by equivalent functional results for the recipients.

Reduced transfusion requirements during major hepatic resection with use of intraoperative isovolemic hemodilution

BACKGROUND

Allogeneic blood transfusion during liver resection for malignancies has been associated with an increased incidence of tumor recurrence and decreased survival in some series. Isovolemic hemodilution (IH) has been utilized in cardiac, orthopedic, and major general surgery procedures to reduce the use of banked blood products. We therefore sought to determine the safety and efficacy of IH during major hepatic resection in an adult population.

METHODS

Thirteen consecutive patients undergoing major hepatic resection with IH were compared with 13 age- and disease-matched controls. The diseases included metastatic colorectal adenocarcinoma (8 versus 9), hepatoma (2 in each group) and other (3 versus 2); and the procedures included total (right or left) hepatic lobectomy (8 versus 11), partial lobectomy (3 versus 1) and trisegmentectomy (2 versus 1).

RESULTS

There was no significant difference in operating time, estimated blood loss, fresh frozen plasma, platelets, amount of crystalloid or colloid infused between the two groups. There was no perioperative morbidity related to IH. The use of IH resulted in a 60% reduction in mean packed red blood cells transfusion during major hepatic resection. Only 38% of patients undergoing IH required packed red cells transfusion, whereas 77% of historical control patients required allogenic transfusion.

CONCLUSION

The use of IH reduces the need for homologous transfusion during major hepatic resection. IH is a safe technique during hepatic resection and is not associated with perioperative morbidity.

Torsion of intraperitoneal renal transplants: imaging appearances

OBJECTIVE

Torsion of a renal transplant is a rare complication with nonspecific clinical manifestations. Prompt detection is necessary to allow surgical treatment and to preserve renal function. We describe the radiologic appearances of torsion of intraperitoneal renal transplants in patients who have undergone simultaneous renal and pancreatic transplantation or dual renal transplantation.

CONCLUSION

Renal transplant torsion should be suspected when a change in renal axis associated with abnormal perfusion occurs in an intraperitoneal kidney.

Acute pancreatitis and fulminant hepatic failure

BACKGROUND

The association of acute pancreatitis with fulminant hepatic failure (FHF) was first recognized in 1973. Since then, few studies have described the clinical profile of the FHF patient with acute pancreatitis. Identification of the distinguishing attributes of pancreatitis in combination with FHF will provide a more sound basis for clinical management. The purposes of this study were to identify distinguishing clinical characteristics of acute pancreatitis in FHF and to compare outcomes with those of patients with acutely decompensated chronic liver disease and acute pancreatitis (DECOMP).

STUDY DESIGN

This was a retrospective survey of 30 patients with FHF and 30 with DECOMP admitted during the period July 1995 to July 1997.

RESULTS

The prevalence of acute pancreatitis in FHF and DECOMP was 33% and 23%, respectively. Acute pancreatitis was associated with severe hepatocellular synthetic dysfunction, renal insufficiency, requirement for endotracheal intubation, increased acuity of illness at the time of ICU admission, more rapid decompensation during the disease, and significantly greater mortality in both the FHF and DECOMP groups.

CONCLUSIONS

In both FHF and DECOMP, acute pancreatitis increases disease acuity and mortality. Acute pancreatitis does not occur with significantly greater frequency in FHF. Implementation of orthotopic liver transplantation may not be warranted in this setting.

Reducing the length of stay after kidney transplantation--the intensive outpatient unit

The need to reduce the costs associated with the initial hospitalization for kidney transplantation has led to the development of outpatient facilities in which patients can be seen on a daily basis. The implementation of a kidney transplant intensive outpatient unit (IOPU) is described. Prior to the opening of the IOPU, the median and mean lengths of stay after kidney transplantation in our program were 14.0 and 18.9 d, respectively. Subsequent to the opening of the IOPU, the median and mean lengths of stay after kidney transplantation have gradually decreased and are currently 5.0 and 7.5 d, respectively. The median inpatient cost of transplantation, excluding organ acquisition charges, has decreased by 54%, from $25516 to $11616. Patient satisfaction has exceeded 80%. The IOPU represents an effective means of reducing the cost associated with transplantation, without sacrificing the quality of care.

Fungaemia due to Cryptococcus laurentii and a review of non-neoformans cryptococcaemia

Cryptococcus laurentii is one of several non-neoformans cryptococci that have rarely been associated with human infection. The spectrum of clinical infection due to non-neoformans species ranges from skin lesions to fungaemia. Most cases of non-neoformans fungaemia have been nosocomially acquired and have been associated with indwelling intravascular catheters and neutropenia. Limited data on in vitro susceptibilities of non-neoformans cryptococci show these species to be more resistant to fluconazole and flucytosine than most Cr. neoformans. Two such cases are presented here.

AvrXa10 contains an acidic transcriptional activation domain in the functionally conserved C terminus

The avrXa10 gene of Xanthomonas oryzae pv. oryzae, the causal agent of bacterial blight of rice, is a member of the avrBs3 avirulence gene family and directs the elicitation of resistance in a gene-for-gene manner on rice lines carrying the resistance gene Xa10. The carboxyl (C) terminus of AvrXa10 has a previously undescribed domain that is structurally similar to the acidic activation domain of many eukaryotic transcription factors in addition to three nuclear localization signal (NLS) sequences. Removal of the C-terminal 38 codons containing the putative activation domain, but retaining the NLS sequences, was concomitant with the loss of avirulence activity. The C-terminal coding regions of avrBs3 and avrXa7 can be replaced by the corresponding region of avrXa10, and the genes retained specificity for the resistance genes Bs3 in pepper and Xa7 in rice, respectively. The avrBs3 and avrXa7 avirulence activities of the hybrid genes were also lost upon removal of the terminal 38 codons. When fused to the coding sequence of the Gal4 DNA binding domain, AvrXa10 activated transcription in yeast and Arabidopsis thaliana. Removal of the carboxyl region severely reduced transcriptional activation. AvrXa10 would have to be localized to the host cell nucleus to function autonomously in transcriptional activation. Consistent with this requirement, mutations in all three NLS sequences of avrXa10 caused a loss in avirulence activity. The findings demonstrate the requirement of the C terminus for AvrXa10 function and the potential for the members of this family of avirulence gene products to enter the host nucleus and alter host transcription.

Dobutamine stress echocardiography for preoperative cardiac risk stratification in patients undergoing orthotopic liver transplantation

This study attempts to evaluate the efficacy of dobutamine stress echocardiography for preoperative cardiac risk stratification in patients undergoing orthotopic liver transplantation. Two hundred twenty consecutively submitted patients were evaluated in preparation for orthotopic liver transplantation. Dobutamine stress echocardiography was performed in 80 patients with known or suspected coronary artery disease. Follow-up information was available in 40 patients in the form of cardiac catheterization and/or outcome from liver transplantation to validate the dobutamine stress echo findings. The prevalence of coronary artery disease in this cohort was 5% and was closely associated with the presence of diabetes mellitus. Dobutamine stress echocardiography, when interpreted as abnormal in the presence of wall motion abnormalities only, is associated with a sensitivity, specificity, and positive and negative predictive value of 100%. Dobutamine stress echocardiography is highly efficacious and should be the screening study of choice to detect coronary artery disease in patients undergoing orthotopic liver transplantation.

The clinical implications of hypophosphatemia following major hepatic resection or cryosurgery

OBJECTIVES

To determine the incidence and predisposing factors leading to postoperative hypophosphatemia after major hepatic surgery and the consequences of this electrolyte abnormality.

DESIGN

A retrospective study.

SETTING

A university tertiary care referral center.

PATIENTS AND METHODS

Thirty-five consecutive patients undergoing either major hepatic resections or cryosurgery from July 1994 through January 1997 were retrospectively reviewed for the occurrence of hypophosphatemia and postoperative complications.

MAIN OUTCOME MEASURES

Prolonged ventilatory support, intensive care unit and hospital stays, and the incidence of postoperative complications.

RESULTS

The overall incidence of hypophosphatemia in our series was 21 (67%) of 35 with a mortality rate of 1 (2.8%) in 35. Mean operative time, estimated blood loss, partial vascular occlusion time, and transfusion requirements were similar between the hypophosphatemic and the nonhypophosphatemic groups. The presence of postoperative complications was significantly greater in the hypophosphatemic group (17 [80%] of 21) vs the nonhypophosphatemic group (4 [28%] of 14) (P<.05). The incidence of antacid use in the hypophosphatemic group (14 [66%] of 21) was significantly higher than the use in the nonhypophosphatemic group (2 [14%] of 14) (P<.05).

CONCLUSIONS

Hypophosphatemia commonly occurs in major hepatic procedures. The presence of moderate hypophosphatemia is associated with the use of antacid therapy but no other perioperative or operative variables. The occurrence of hypophosphatemia correlates with an increased incidence of postoperative complications. Awareness of this entity can direct aggressive replacement of phosphates and avert the occurrence of severe hypophosphatemia and associated complications.

Apoptosis and hepatic allograft reperfusion injury

Necrosis and apoptosis are distinct, but nonexclusive mechanisms of cell death. Until recently, investigators have focused upon necrosis as the sine qua non of lethal cell injury. Specifically, within the realm of liver transplantation, preservation strategies dealing with ischemia/reperfusion injury have concentrated upon minimizing the biochemical and histologic correlates associated with necrosis. Little is known of the role of apoptosis in reperfusion injury in human liver transplantation. Post-reperfusion liver biopsies from 35 patients were retrospectively analyzed for histologic evidence of necrosis. Apoptosis was identified histologically and using a chromogenic technique of in situ labeling of fragmented DNA. The number of apoptotic cells increased in parallel with the necrosis reperfusion score in a significant fashion (p = 0.003 by ANOVA). There was not a Zone 1, 2 or 3 predominance to the histologic distribution of apoptotic cells. The recipient peak serum transaminase values were also noted to increase with the reperfusion score (p = 0.001 by ANOVA). These results suggest that: 1) apoptosis occurs in the setting of reperfusion injury during human orthotopic liver transplantation (OLT); and 2) the extent of apoptosis increases in parallel with pathologic and biochemical parameters of reperfusion injury. Given the distinct nature of apoptosis and the highly regulated and conserved pathway for its initiation, inhibition of apoptosis with specific molecular targets, may serve to decrease allograft reperfusion injury.

Dopamine transporter mRNA is increased in the CNS of Zucker fatty (fa/fa) rats

The obese Zucker fa/fa rat is characterized by hyperinsulinemia, obesity, and altered monoamine metabolism in the central nervous system (CNS). It has been proposed that the changes in monoamine metabolism may contribute to the metabolic pathophysiology of these animals. Because it has been reported that insulin may regulate the catecholamine reuptake transporters, which terminate monoaminergic synaptic signaling, in the present study we tested whether messenger ribonucleic acid (mRNA) levels for the noradrenergic (NE) or dopaminergic (DA) transporters were altered in obese fa/fa vs. lean Fa/Fa Zucker rats. We found significantly elevated DA transporter levels in both the ventral tegmental area/substantia nigra pars compacta (VTA/SNc) and zona incerta (ZI) of obese Zucker fa/fa rats (164 +/- 24% of control levels, p = .024; and 316 +/- 61% of control levels, p = .019, respectively). Measurement of mRNA for tyrosine hydroxylase (TH), the rate-limiting enzyme for NE and DA synthesis revealed no effect of the fa gene in either NE or DA neurons. These findings suggest that increased DA clearance, and perhaps decreased DA signaling, may occur in the obese Zucker fa/fa rat.

Epstein-Barr virus-related posttransplantation lymphoproliferative disorder involving pancreas allografts: histological differential diagnosis from acute allograft rejection

The clinical and pathological features of acute pancreas allograft rejection and involvement of the graft by posttransplantation lymphoproliferative disorders (PTLD) overlap. Because the treatment is diametrically opposite in these two types of lesions, an accurate diagnosis is essential. The histological features in pancreas allograft needle biopsy specimens (n=7) and pancreatectomies (n=4) from four patients with Epstein-Barr virus (EBV)-related PTLD were compared with the material from 14 patients who did not develop PTLD after 12 to 58 months of follow-up and whose biopsy specimens (n=10) and pancreatectomies (n=10) showed rejection-related heavy or atypical inflammatory infiltrates. Features typical of rejection included most (>75%) being of mixed small and large, activated-appearing T lymphocytes, a smaller component of mature plasma cells, and variable numbers of eosinophils. Cytologically atypical cells were always a minority (< 10%). The inflammation involved the septal spaces with proportional involvement of the exocrine tissue, veins, ducts, and arteries. The inflammation was particularly targeted against the acini and was associated with acinar cell damage. Features characteristic of PTLD were nodular and expansile infiltrates, composed of a significant proportion of atypical, plasmacytoid B cells (40% to 70% of the infiltrate); Reed-Sternberg-like cells were noted in two patients. The infiltrates involved the parenchyma randomly with no apparent affinity for the acinar tissue. Extensive infiltration of the peripancreatic soft tissues was common. Arterial walls were not involved in PTLD unless there was concurrent acute vascular rejection. Features identified in both conditions were foci of necrosis and infiltration of venous walls with associated endotheliitis. Samples with concurrent PTLD and acute rejection showed combinations of these features. In situ hybridization for EBER (Epstein-Barr-encoded RNAs) was positive only in the samples from patients with PTLD. Based on the assessment of morphological differences and the selective use of relatively simple ancillary techniques, PTLD can be correctly diagnosed even in small tissue samples such as needle biopsy specimens. An early diagnosis will lead to the appropriate treatment.

Primary hepatic low-grade B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) associated with primary biliary cirrhosis

We describe a case of low-grade B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) arising in the liver of a patient with early-stage primary biliary cirrhosis (PBC). The patient, a 62-year old woman, presented with abnormal liver function tests, a positive antimitochondrial antibody titer (1:160), and a liver mass. The resected mass, 6.0 x 5.0 x 4.0 cm, had the features of MALT-type lymphoma. The neoplastic cells were small lymphoid cells of B-cell lineage that surrounded reactive lymphoid follicles and infiltrated bile ductules to form lymphoepithelial lesions. The uninvolved liver had histologic evidence of early stage PBC, characterized by segmental duct destruction with granulomata and an inflammatory infiltrate in the portal triads composed of lymphocytes, plasma cells, and occasional eosinophils. A periportal lymph node showed histologic features of the hyaline-vascular type of Castleman's disease, without evidence of malignant lymphoma. Low-grade B-cell lymphomas of the MALT type rarely arise in the liver and, to our knowledge, have not been reported previously in association with PBC. The association in this case suggests that chronic antigenic stimulation as a result of PBC induced the accumulation of acquired MALT, which subsequently transformed to low-grade B-cell lymphoma.

Insect resistance of transgenic tobacco expressing an insect chitinase gene

Chitinase expression in the insect gut normally occurs only during moulting, where the chitin of the peritrophic membrane is presumably degraded. Thus, insects feeding on plants that constitutively express an insect chitinase gene might be adversely affected, owing to an inappropriately timed exposure to chitinase. This hypothesis was tested by introducing a cDNA encoding a tobacco hornworm (Manduca sexta) chitinase (EC 3.2.1.14) into tobacco via Agrobacterium tumefaciens-mediated transformation. A truncated but enzymatically active chitinase was present in plants expressing the gene. Segregating progeny of high-expressing plants were compared for their ability to support growth of tobacco budworm (Heliothis virescens) larvae and for feeding damage. Both parameters were significantly reduced when budworms fed on transgenic tobacco plants expressing high levels of the chitinase gene. In contrast, hornworm larvae showed no significant growth reduction when fed on the chitinase-expressing transgenics. However, both budworm and hornworm larvae, when fed on chitinase-expressing transgenic plants coated with sublethal concentrations of a Bacillus thuringiensis toxin, were significantly stunted relative to larvae fed on toxin-treated non-transgenic controls. Foliar damage was also reduced. Plants expressing an insect chitinase gene may have agronomic potential for insect control.

Successful use of chronic epoprostenol as a bridge to liver transplantation in severe portopulmonary hypertension

BACKGROUND

Portopulmonary hypertension, defined as mean pulmonary artery pressure >25 mmHg in the presence of a normal pulmonary capillary wedge pressure and portal hypertension, is a known complication of end-stage liver disease that has been associated with high morbidity and mortality at the time of liver transplantation. We have recently reported the successful treatment of portopulmonary hypertension with chronic intravenous epoprostenol and now report the first patient with severe portopulmonary hypertension successfully treated with epoprostenol who subsequently underwent successful liver transplantation.

METHODS

A patient with severe portopulmonary hypertension was treated with intravenous epoprostenol, 23 ng/kg/min, for a 4-month period, after which the portopulmonary hypertension resolved and the patient underwent successful liver transplantation.

RESULTS

The patient was discharged, continues to do well, and at 3 months is off epoprostenol with near normal pulmonary artery pressures.

CONCLUSIONS

Chronic epoprostenol, in conjunction with a multidisciplinary, well-planned perioperative evaluation and treatment plan, may be the answer to a heretofore untreatable disease.

Mycophenolate mofetil reduces the risk of acute rejection less in African-American than in Caucasian kidney recipients

BACKGROUND

Multicenter clinical trials have shown that mycophenolate mofetil (MMF) reduces the risk of acute rejection, but it is unknown whether African-Americans constitute a subgroup of recipients less likely to benefit from MMF.

METHODS

This study compared the acute rejection rates within 6 months of kidney transplantation in MMF-treated transplant patients with those on azathioprine (AZA) at a single center. The study population consisted of 353 consecutive recipients of cadaver or living donor kidney transplants. African-Americans constituted 43% of the patients on AZA and 49% of the patients on MMF. Variables used in a Cox regression analysis included MMF immunosuppression, recipient race, type of transplant, delayed graft function, postoperative immune induction, average cyclosporine trough level, and HLA mismatch.

RESULTS

Significantly fewer patients on MMF experienced a biopsy-proven rejection episode than those treated with AZA (24% vs. 42%, respectively; relative risk [RR]=0.57, P=0.001). This decrease in risk was greater in Caucasian transplant recipients (MMF vs. AZA: 16% vs. 46%, RR=0.35, P < 0.001) than in African-American patients (32% vs. 36%, RR=0.88, P=0.6). Within each race stratum, the mean cyclosporine trough levels averaged over 2-week intervals were nearly identical for AZA- compared with MMF-treated patients. In the regression model, the effect of MMF on the incidence of rejection was again less in African-American than in Caucasian patients.

CONCLUSIONS

Kidney recipients treated with MMF have a significantly lower risk of acute rejection within 6 months of transplantation than those given AZA. This reduction in risk is significantly less in African-American recipients than Caucasians.

A novel approach to the treatment of chronic allograft nephropathy

BACKGROUND

Progressive deterioration of renal function in kidney transplant recipients is the leading cause of graft failure. Both nonimmunologic and immunologic mechanisms contribute to this deterioration.

METHODS

Twenty-eight cyclosporine (CsA)-treated renal transplant recipients (21 cadaveric, 5 living, 2 simultaneous kidney-pancreas) with progressive deterioration of renal function were prospectively enrolled in a clinical trial and had their immunosuppressive regimen changed 24.3+/-7.7 months after transplant. All patients had their CsA dose reduced by 50%, azathioprine was discontinued, and mycophenolate mofetil was added to the medical regimen. The mean creatinine of the patients at the initiation of the change in immunosuppression was 3.5+/-1.2 mg/dl (range 1.9 to 6.2 mg/dl).

RESULTS

Before the change in immunosuppression, the mean loss in renal function as indicated by the least-squares slope of the reciprocal of creatinine versus time was -0.006+/-0.002 (mg/dl)-1 per month. The change in immunosuppression significantly decreased the rate of loss in renal function for most patients when compared with their pretreatment values with a mean slope of 0.007+/-0.003 (mg/dl)-1 per month (P=0.003). Renal function improved in 21 of 28 patients. Only one patient had continued deterioration of renal function. In a multivariate analysis adjusting for CsA dose, mean arterial blood pressure, and baseline creatinine, the change in immunosuppression was significantly associated with improved renal function (P=0.02). There were no acute rejections after the immunosuppression change.

CONCLUSIONS

We conclude that adding mycophenolate mofetil and reducing CsA in patients with chronic deterioration of graft function is well tolerated and results in a short-term improvement in renal function.

Use of renal allografts from donors positive for hepatitis B core antibody confers minimal risk for subsequent development of clinical hepatitis B virus disease

BACKGROUND

The risk associated with transplantation of renal allografts from hepatitis B virus core antibody-positive (HBcAb(+)), hepatitis B virus surface antigen-negative (HBsAg(-)) donors is not well defined.

METHODS

Over 4 years, we performed 45 kidney transplants from IgG HBcAb(+), IgM HBcAb(-), HBsAg(-) donors into recipients with a history of prior hepatitis B virus (HBV) infection or reported vaccination. We examined HBV-related outcomes in these 45 patients, in comparison with 45 recipients of allografts from HBcAb(-) donors (matched for transplant type, date, and pretransplant HBV antibodies). We sought evidence for HBV transmission by testing posttransplant sera for the presence of HBcAb, hepatitis B virus surface antibody, and HBsAg. Additionally, we analyzed alanine aminotransferase profiles and allograft survival rates for all patients.

RESULTS

No patient receiving an allograft from an HBcAb(+) donor developed clinical HBV infection. No patient receiving an allograft from an HBcAb(+) donor had HBsAg detected through retrospective testing of stored sera or through prospective routine clinical evaluation and care. However, among the HBcAb(+) kidney recipients, 27% developed new HBcAb and/or hepatitis B virus surface antibody after transplant; in contrast, only 4% of control patients developed new antibody responses (relative risk=4.94; confidence interval 1.07-22.83). Among the recipients of HBcAb(+) organs, 18% developed elevated transaminases after transplant, in comparison with 36% of the controls. No association was found between "seroconverter" status and elevated alanine aminotransferase profiles in either group.

CONCLUSIONS

Transplantation of renal allografts from HBcAb(+), HBsAg(-) donors was not associated with clinically detectable HBV disease or antigenemia. However, recipients had a significantly increased risk of HBV seroconversion, consistent with exposure to HBV antigen. These results suggest that HBcAb(+) kidneys can be safely used if transplanted into appropriate recipients, but highlight the need for effective HBV vaccination and vaccine-response monitoring in potential recipients.

Selective bowel decontamination in hospitalized patients awaiting liver transplantation

BACKGROUND

Infection remains a major contributor to morbidity and mortality following orthotopic liver transplantation (OLT). Selective bowel decontamination (SBD) in hospitalized patients is one strategy for prophylaxis.

METHODS

A retrospective case-control study was performed using 18 consecutive hospitalized patients receiving SBD prior to OLT during the period September 1995 to September 1996. Eighteen consecutive hospitalized patients without SBD transplanted during the period March 1995 to September 1995 served as a historical control group.

RESULTS

Selective bowel decontamination was associated with a significantly decreased prevalence of positive cultures for gram-negative bacteria and fungi and reduced overall hospital charges.

CONCLUSION

In hospitalized patients awaiting OLT, SBD is an effective prophylactic measure against infectious morbidity associated with gram-negative bacteria and fungi.