Etiological agents of bacteremia in the early period after liver transplantation

Bacteremia is one of the major infections in orthotopic liver transplantation (OLT). The study of 83 adults who underwent OLT from 2001 to 2004, included patients followed prospectively from the day of transplantation to 4 weeks after the procedure by bacteriological cultures. The microorganisms were investigated according to standard National Committee for Clinical Laboratory Standards (NCCLS) procedures. Blood samples were examined in 59 recipients (71.1%) before and in 76 patients (91.6%) during the month after transplantation. Among 249 investigated samples, 96 were positive, as cultured from 19 recipients before OLT and 48 patients afterward. The most common were Gram-positive cocci (n = 71) and coagulase-negative staphylococci (n = 52), including methicillin-resistant coagulase-negative staphylococci (MRCNS). Enterococcus spp. occurred in 9 isolates (high-level aminoglycoside-resistant enterococci [HLAR] strains were cultured). We cultured the Enterobacteriaceae family (n = 16 isolates) and (n = 15 isolates), Gram-negative nonfermenting rods some of which were extended spectrum beta-lactamase producing [ESBL(+)] strains. The predominance of Gram-positive cocci was caused by CNS, and the use of prophylaxis to reduce Gram-negative bacteria. The increased rate of isolation of bacteria with multidrug resistance (MDR) to antimicrobial agents may be due to their frequent use for prophylaxis of bacterial infections in OLT. These MDR bacterial strains caused severe BSI after OLT.     

Surgical site infections in liver recipients in the early posttransplantation period: etiological agents and susceptibility profiles

OBJECTIVE: This study evaluated the frequency of microbial isolates and their susceptibility profiles from cultures at the surgical site of 83 liver recipients in the early posttransplantation period. PATIENTS AND METHODS: We prospectively collected microbiologic culture data on 83 adult patients undergoing orthotopic liver transplantation (OLT) using standard procedures and commercially available tests. Susceptibility of the strains to antibacterial agents was performed by the Clinical and Laboratory Standards Institute (CLSI) guidelines. RESULTS: All patients were followed prospectively for the first 4 weeks after surgery. Among 284 microbial isolates from clinical surgical site samples in 80 liver recipients, cultures were positive in 110 samples. The most commonly isolated species were: Gram-positive cocci (n = 222 isolates, 78%) with dominance of methicillin-resistant coagulase-negative staphylococci (MRCNS; 42%) and high-level aminoglycoside-resistant enterococci (HLAR strains; 24.3%). Gram-negative bacteria were identified in 21.5% of positive cultures, including 30 strains (24%) from the Enterobacteriaceae family, with 13.3% of extended spectrum beta-lactamase producers [ESBL(+)]. Significant differences (P = .0012) were observed during the analysis of changes in the occurrence of Gram-positive bacteria isolated from the surgical site in the first week versus the second to the end of the fourth week. CONCLUSION: Gram-positive bacteria predominated as 78% of isolates.     

Outcome of infections caused by multiple drug-resistant bacteria in liver transplant recipients

OBJECTIVE: To evaluate the impact of infections caused by multiple-drug-resistant (MDR) bacteria on the clinical outcome of liver transplant recipients. METHODS: Retrospective study including all episodes of bacterial infection diagnosed in patients undergoing liver transplantation from January 19, 1999, to June 30, 2002. The diagnosis of bacterial infection required microbiological documentation. Mortality associated with episodes of infection by MDR bacteria was compared to that observed after antibiotic-susceptible bacterial infections. RESULTS: Among 99 patients undergoing liver transplantation during the study period, there were 57 episodes of bacterial infections. Gram-negative bacilli were the predominant etiologic agents (76%) and Pseudomonas aeruginosa was the most frequent bacterial species found in these cases (23 isolates, 28%). Thirty-six episodes of infection (63%) were caused by MDR bacteria. Mean time after transplantation to the diagnosis of infection was 17 days. Mortality associated with episodes of MDR bacterial infections (nine deaths, 25%) was not significantly different from that observed during episodes of antibiotic-susceptible bacteria (five deaths, 24%; P =.92). CONCLUSION: These data suggest that resistance to multiple antimicrobial agents does not have an impact on the mortality associated to bacterial infections in liver transplant recipients.     

原位肝移植术后早期细菌、真菌感染的临床研究

目的:探讨原位肝移植术后病人细菌、真菌感染的临床特点,常见病原菌及其耐药性,总结防治经验。方法:就74例原位肝移植病人术后,针对感染进行各个系统的定期检测,观察感染发生时间、部位、病原谱及药物敏感性等指标。结果:74例肝移植病人中,术后并发感染者48例,感染率为64.9%;包括单纯细菌感染24例(32.4%),单纯真菌感染6例(8.1%),混合感染(细菌合并真菌)18例(24.3%)。其中革兰阴性杆菌共占34.6%,革兰阳性球菌占34.1%。真菌占31.3%。感染大部分发生在术后1个月以内。最常见的感染部位是呼吸道,其次为尿道和胆道。感染的病原菌依次为金黄色葡萄球菌、铜绿假单胞菌和肺炎克雷伯菌。病原菌中革兰阴性杆菌对头孢吡肟和美罗培南敏感性较高,革兰阳性球菌对万古霉素和替考拉宁敏感性较高。结论:肝移植病人术后感染是影响存活的重要因素,应重视移植术前后对病人的监测和预防性抗生素应用等措施。在处理感染病情时,应综合考虑病原菌谱、药敏结果、多部位复合感染及混合感染等因素。     

Detection of Clostridium difficile in stool samples from patients in the early period after liver transplantation

OBJECTIVE: We examined the frequency of detection of Clostridium difficile (CD) toxins compared with the recovery of C. difficile in stool specimen cultures among orthotopic liver transplant (OLT) patients with nosocomial diarrhea in the early period. MATERIALS AND METHODS: The study included stool samples obtained during the first 30 days after OLT in adults who were suspected of CD-associated diseases. The identification of cultured CD strains was performed by standard microbiological methods. The presence of CD toxins was assayed using a commercial immunoassay. RESULTS: All patients were followed prospectively for CD infections from the date of OLT for the first 4 weeks after surgery. Among 54 samples, 16.7% were culture-positive for CD. CD toxins were tested on 54 samples, yielding 63% toxin-positive samples and 30% toxin- and culture-negative results. In the first week after OLT, samples from 19 patients were subjected to CD investigation. Among 19 samples positive for toxin, 52.6% of all samples were culture-negative. We analyzed 35 samples from the second to the fourth week after OLT in 31 recipients. Among 35 samples, 68.6% and 25.7% were positive for CD toxin and for culture, while 20% of samples were negative for toxin and culture. CONCLUSION: In our study, 63% of samples were toxin-positive with 16.7% yielding growth of CD and 30% being negative for toxins and cultures.     

Bacterial and Fungal Infections in the Early Post-transplantation Period After Liver Transplantation: Etiologic Agents and Their Susceptibility

Objective

It has been reported in many studies that one of the main factors influencing morbidity and mortality in patients receiving transplants is infection after transplantation.

Patients and Methods

The study included 190 adult patients undergoing orthotopic liver transplantation (OLT) between September 2001 and December 2007. All the patients were followed prospectively for infections from the OLT date and during the first 4 weeks after surgery. Immunosuppression consisted of steroids and tacrolimus. Antimicrobial prophylaxis included piperacillin/tazobactam, fluconazole, and selective bowel decontamination (SBD) was performed. Samples of clinical materials were investigated for microbiological cultures. The micro-organisms were cultured and identified in accordance with standard bacteriological procedures. Susceptibility testing was performed using Clinical and Laboratory Standards Institute procedures.

Results

From 190 OLT recipients, 2213 clinical samples were obtained for microbiological examination. Positive cultures were found in 27.2% (n = 603) of all samples tested; 1252 strains were collected. Gram-positive bacteria were found in 64.1% (n = 802), Gram-negative bacteria were found in 31.6% (n = 396), and fungal strains were isolated in 4.3% (n = 54). Surgical site specimens (n = 1031) were obtained from 190 recipients during the first month after transplantation. Positive cultures accounted for 29.2% (n = 301) of all samples tested. Among the isolated microbial strains (n = 677), most common were Gram-positive bacteria (73.7%; n = 499). Gram-negative bacteria comprised 25.1% (n = 170). There were fungal strains in 1.2% (n = 8). There were 539 urine specimens. Positive cultures accounted for 16.7% (n = 90) of those. Among the isolated microbial strains (n = 210), most common were Gram-negative bacteria (62.4%; n = 131). Gram-positive bacteria comprised 28.6% (n = 60) and fungi 9% (n = 19). There were 549 blood specimens. Positive cultures were found in 30.6% (n = 168) of all samples tested. Among the isolated microbial strains (n = 263), most common were Gram-positive bacteria in 72.3% (n = 190); Gram-negative bacteria were found in 26.2% (n = 69), and fungal strains were isolated in 1.5% (n = 4). There were 69 respiratory tract specimens. Positive cultures were found in 46.4% (n = 32) of all samples tested. Among the isolated microbial strains (n = 84), most common were Gram-positive bacteria (51.2%; n = 43); Gram-negative bacteria comprised 27.4% (n = 23) and fungi 21.4% (n = 18).

Conclusions

(1) Surgical site samples were predominated samples after LTx. (2) Our study showed Gram-positive bacteria were 64.1% (n = 802), Gram-negative bacteria, 31.6% (n = 396) and fungal strains isolated in 4.3% (n = 54). (3) The increased proportion of isolates of multi-drug–resistant bacterial strains (methicillin resistant coagulase negative Staphylococcus, vancomycin-resistant Enterococcus, high-level aminoglycoside resistance, and extended- spectrum β-lactamase). (4) These data indicate strict cooperation infection control procedures in these patients.     

Late cytomegalovirus disease following liver transplantation

The widespread use of antiviral prophylaxis or preemptive therapy among orthotopic liver transplantation (OLT) recipients has reduced the occurrence of early cytomegalovirus (CMV) disease. Late disease is increasingly reported. Little is known about CMV disease occurring beyond the first year after transplantation. The aim of this study was to evaluate the occurrence of CMV disease two or more years after OLT and to determine its risk factors and clinical features. Eighty-one consecutive OLT recipients followed for 2 years or longer after transplantation were included in the study. Data were collected on demographic and clinical variables, clinical presentation, treatment, and outcome of late CMV disease. Late CMV disease occurred in 7/81 liver recipients (8.5%) at a mean time of 5.9 years after OLT (range: 3.5--9.3, median: 6.3 years). All seven patients were women, with a mean age of 47.7 years (range: 26--60, median: 59 years). There was no association between the development of late CMV disease and the occurrence of rejection episodes, treatment with corticosteroids, or the early use of antiviral prophylaxis. Clinical presentation included fever and disturbed liver functions in all patients, one patient had concurrent CMV pneumonitis and one CMV retinitis. Though all patients responded to ganciclovir, two had recurrent disease episodes and one patient died of secondary bacterial sepsis. Late-onset CMV disease can occur several years after OLT. Although it manifests classic clinical features of early disease, it is not associated with traditional risk factors and its pathogenesis may differ from that of early disease.     

肝移植术后细菌性感染的病原学特征及分布特点

目的研究肝移植术后细菌感染的流行病学规律。方法回顾性分析451例患者原位肝移植术后细菌学资料。结果肝移植术后239例患者出现细菌感染,细菌感染率为53．0％,共分离出菌株304株,其中革兰阳性（G^＋）球菌占59．9％（182／304）,革兰阴性（G^-）杆菌占40．1％（122／304）。易感器官依次为呼吸道和胆道,感染发生率分别为81．5％（248／304）,15．1％（46／304）。呼吸道感染以G^＋菌为主,占65．3％,胆道感染以G^-为主,占60．9％,两者有显著性差异（P〈0．01）。结论肝移植术后细菌感染率高,主要以G^＋球菌感染为主,条件致病菌及多重耐药菌株较多见。肝移植术后细菌感染的菌群与部位间有明显相关关系,在预防或治疗感染时应针对不同感染部位采取不同措施。     

Hepatic abscess after liver transplantation: 1990-2000

BACKGROUND: Infections following solid-organ transplants are a major cause of morbidity and mortality. Few studies have reported the complications of hepatic abscesses. METHODS: This investigation consisted of a retrospective chart review of all solid-organ transplant recipients from 1990 to 2000. Criteria for diagnosis included parenchymal hepatic lesions, positive cultures from liver aspirates or blood cultures, or both, and a compatible clinical presentation. RESULTS: Of 2,175 recipients of all organ transplants (heart, lung, kidney, liver, pancreas), we identified 12 patients who had experienced 14 episodes of hepatic abscess, all in liver transplant recipients. Median time from transplant to hepatic abscess was 386 days (range 25-4,198). The most common predisposing factor was hepatic artery thrombosis (HAT), which occurred in eight patients, and was diagnosed at an average of 249 days (range 33-3,215) after transplantation. Clinical presentation of hepatic abscess was similar to that described in non-immunosuppressed patients. All but one patient showed hypoalbuminemia (<3.5 g/dL); those with HAT also had significantly elevated lactate dehydrogenase. Liver aspirates grew gram-positive aerobic bacteria (50% of isolates), gram-negative aerobic bacteria (30%), and anaerobes and yeasts (10% each). Patients received an average of 6 weeks of intravenous antibiotic therapy. Catheter drainage was successful in 70% of cases; and five patients required retransplantation. Altogether, five of the patients died, yielding a mortality rate of 42%. CONCLUSIONS: Hepatic abscess, a rare complication after liver transplantation, was frequently associated with hepatic artery thrombosis. Mortality was higher than in patients who had not undergone transplantation. Prolonged antibiotic therapy, drainage, and even retransplantation may be required to improve the outcome in these patients.     

Etiologic Agents of Bacteremia in the Early Period After Simultaneous Pancreas–Kidney Transplantation

Background

Bacteremia is among the known complications in simultaneous pancreas-kidney transplantation (SPKT). This study evaluated the frequency of microbial isolates and their susceptibility profiles among cultures of clinical samples obtained from blood and from the tips of blood vessel catheters of 26 SPKT recipients suspected of bacteremia in the early posttransplant period.

Patients and Methods

Data on microbiologic blood cultures of 26 adult patients undergoing SPKT were collected prospectively from 2001 to the end of 2006. The isolation and identification of cultured microorganisms were performed according to standard microbiological procedures and commercially available tests. The susceptibility of the strains to antibacterial agents was established by the Clinical and Laboratory Standards Institute guidelines.

Results

All patients were followed prospectively for the first 4 weeks after surgery. Among 66 clinical samples, there were 23 microbial isolates from blood samples of 17 recipients and catheter tips of 12 recipients. The most common isolates were Gram-positive bacteria (73.9%) with domination of staphylococci (64.7%) and MRCNS strains (81.8%). Gram-negative bacteria comprised 17.4% of positive cultures, whereas yeast-like fungi, 8.7% with a predominance of Candida glabrata.

Conclusion

Our study showed predominately Gram-positive bacteria in 73.9% of isolates. The increased proportion of multi-drug-resistant bacteria and fungi to antimicrobial agents may be due to the frequent use of these agents for prophylaxis of bacterial infections in patients.     

The use of liver grafts from donors with bacterial meningitis

BACKGROUND: The shortage of suitable donors for transplantation is a worldwide problem. The use of cadaveric donors with bacterial meningitis may be associated with an increased risk of sepsis. We report the results of orthotopic liver transplantation (OLT) from 33 such donors between 1989 and 1999. METHODS: The hospital records of recipients from cadaveric donors with meningitis (study group) were retrospectively reviewed and compared with matched recipients from cadaveric donors dying from causes other than meningitis (recipient-matched control group). RESULTS: A total of 34 recipients underwent 21 whole, 10 reduced, and 3 split liver transplants from 33 cadaveric donor livers with bacterial meningitis. The donor meningitis pathogens were Neisseria meningitidis (n=14), Streptococcus pneumoniae (n=4), Haemophilus influenzae (n=1), Streptococcus species (n=2), and unknown (n=12). Twenty-seven patients had an elective OLT and seven patients had an emergency OLT. Adequate antimicrobial therapy before organ procurement and after transplant was administrated. The mean posttransplant follow-up was 37 months (range: 1 day-106 months). There was no difference in recipient and graft survival rates between the study and the recipient-matched groups. In the study group, there were no infectious complications caused by the meningeal pathogens. Overall patient survival rates were 79%, 76%, 72%, and 72% at 1, 6, 12, and 60 months, respectively. Graft survival was 77%, 70%, 65%, and 65% at 1, 6, 12, and 60 months, respectively. The survival rate in elective cases was significantly better than emergency cases (P<0.05). CONCLUSION: Liver transplantation from donors with bacterial meningitis is a safe procedure provided both donors and recipients receive adequate antimicrobial therapy.     

Surgical Site Infections in the Early Posttransplant Period After Simultaneous Pancreas–Kidney Transplantation

Objective

This study evaluated the frequency of microbial isolates and their susceptibility profiles among cultures from the “surgical site” of 26 simultaneous pancreas-kidney (SPKT) recipients in the early posttransplant period.

Patients and Methods

Data on microbiologic cultures of 26 adult patients undergoing SPKT were collected prospectively from 2001 to the end of 2006. The isolation and identification of cultured micro-organisms was performed according to standard microbiological procedures and commercially available tests. Susceptibility of the strains to antibacterial agents was made by the Clinical and Laboratory Standards Institute (CLSI) guidelines.

Results

All patients were followed prospectively for the first 4 weeks after surgery yielding 168 microbial isolates from the surgical site. The most commonly isolated organisms were Gram-positive bacteria (65.5%) with domination of staphylococci (52.7%) as methicillin-resistant S aureus and methicillin-resistant coagulase-negative staphylococci. The second most common were enterococci (33.6%) with the presence of an high level aminoglycoside-resistant strains (64.9%) and vancomycin-resistant strains (2.7%). Gram-negative bacteria comprised 19% of positive cultures; among them were isolated extended spectrum beta-lactamase producers and carbapenem-resistant strains. Yeast-like fungi comprised 15.5% of positive cultures. In conclusion, we observed predominantly Gram-positive bacteria, comprising 65.5% of isolates. The increased proportion of multi-drug-resistant bacterial isolates may be due to the frequent prophylaxis of bacterial infections in patients.     

Postoperative severe pneumonia in adult liver transplant recipients

Severe pneumonia in adult liver transplantation (OLT) recipients is a dangerous condition with significant morbidity and mortality. To analyze the risk factors for postoperative severe pneumonia in OLT patients, we collected data from 132 consecutive adult patients who underwent OLT between February 1999 and April 2004. According to the American Thoracic Society consensus statement, episodes of severe pneumonia were observed in 24 patients (18.2%). We retrospectively reviewed the etiology diagnosis, treatment, and prognosis of the 24 recipients. Bacteria were responsible for 95.8% of these episodes (23 of 24), fungi for 16.7% (4 of 24) and viruses for 4.4% (1 of 24). Twenty-six percent of the bacterial pneumonias were due to Streptococcus alpha hemolyticus. The mortality rate was 37.5% (9 of 24) for patients with severe pneumonia versus 7.4% (8 of 108, P = .004) for patients without pneumonia. Two cases with hepatorenal syndrome died, and three patients with coinfection by bacteria and fungi died. Acute rejection episodes occurred in 15 patients, four of whom died. Mechanical ventilation and tracheotomy were required in 13 cases (54%). Six who experienced prolonged intubation died. Sputum and pleural fluid cultures helped to establish a diagnosis in 91.7% (22 of 24) of cases. Twenty cases (83%) underwent reduction in the immunosuppressive regimen. Patient age, intraoperative transfusion requirements, extubation time, and hospital stay were fatal predictors of prognoses. We concluded that early detection of the responsible pathogen; timely and specific diagnosis; reduction in the immunosuppressive regimen; appropriate treatment with reliable, effective techniques; and implementation of sensitive culture-based antibiotics was an effective strategy to treat severe adult pneumonia in liver transplantation recipients.     

Steatotic liver transplantation in the mouse: a model of primary nonfunction

BACKGROUND: The number of potential donor organs deemed suboptimal for transplantation because of hepatic steatosis is rising as the obesity rate increases. However, no mouse transplant model has been described within the framework of hepatic steatosis. We describe the development of and our initial experience with a steatotic mouse orthotopic liver transplant model using the ob/ob mouse. This model is technically achievable and functionally mimics primary nonfunction. MATERIALS AND METHODS: Adapting techniques of a nonarterialized murine transplant model, C57BL6 ob/ob mice aged 5-7 weeks (26-35 g) and lean controls served as liver donors and recipients. Orthotopic liver transplantation (OLT) was performed using a two-cuff technique at the infrahepatic cava and portal vein. The suprahepatic cava was anastomosed end to end, and the bile duct was stented. The hepatic artery was not reconstructed. RESULTS: Lean-to-lean OLT was performed with 70% (n = 10) long-term survival. ob/ob-to-age-matched lean recipients had 0% (n = 10) survival because of size discrepancy. ob/ob livers were transplanted to size-matched lean recipients (>3 months old) with short-term survival of 30% (n = 10). These mice survived the operation, awakened, but expired within 24 h. Serum transaminases revealed a significantly higher injury profile in the recipients of the steatotic livers, and histology showed massive centrilobular coagulative necrosis with hemorrhage, the overall picture being that of primary nonfunction. CONCLUSIONS: This novel use of the ob/ob mouse for OLT provides us with a model for steatotic transplantation with primary nonfunction as the end point and may help to better understand the response of the steatotic liver to the insult of transplantation.     

Early Bacteremia After Solid Organ Transplantation

Objective

Bloodstream infections (BSI) are a major cause of morbidity and mortality after solid organ transplantation. Our aim was to analyze early BSI after solid organ transplantation.

Materials and Methods

A prospective cohort study included patients undergoing a kidney, simultaneous kidney-pancreas (SPK), or orthotopic liver transplantation (OLT) from 2003-2007. We prospectively collected demographic variables, underlying chronic diseases, transplantation procedures, and posttransplant complications. Recorded cases of BSI were defined as significant according to CDC criteria. Early BSIs were considered to be those appearing within 30 days posttransplantation.

Results

During the study period, we performed 902 transplantations: 474 renal, 340 liver, and 88 pancreas. Seventy episodes of early BSI were diagnosed in 67 patients (7.4%). The incidences of BSI according to the type of transplantation were: 4.8% in renal, 4.5% in SPK, and 12% in OLT (P < .001). Sixty-three percent of the bacteria isolated were gram-negative, the most frequent being Escherichia coli, of which 18 (54%) were extended-spectrum beta-lactamase-producing (ESBL), and Pseudomonas aeruginosa, of which 18 (31%) were multidrug-resistant. The most frequent gram-positive bacteria were coagulase-negative staphylococci (20%). The urinary tract was a frequent source of BSI (27%), followed by a catheter (18%). Two patients (3%) died, both liver recipients, but neither death was related to the BSI.

Conclusions

In our setting, the incidence of early BSI among solid organ transplant recipients was high, especially liver recipients, but with low associated mortality. The most frequent sources of infection were urinary tract and catheter. Gram-negative BSI showed a high rate of multidrug resistance.     

Urinary tract infections in the early posttransplant period after liver transplantation: etiologic agents and their susceptibility

Background

We performed an analysis of etiologic agents for urinary tract infections in the early posttransplant period after orthotopic liver transplantation (OLT) in adult recipients.

Patients and Methods

The study covered the first 4 weeks after OLT of 190 patients from September 2001 to the end of 2007. Immunosuppression consisted of steroids and tacrolimus. Antimicrobial prophylaxis was piperacillin/tazobactam, fluconazole, and SBD. Urine samples were cultured to identify microorganisms in accord with standard microbiological procedures and to test susceptibility using Clinical Laboratory and Standards Institute guidelines.

Results

Urine specimens (n = 539) examined from 185 recipients (97.4%) showed 210 microbial strains. The most common were Gram-negative (n = 131; 62.4%) with predominance of Escherichia coli (28.2%), Enterobacter cloacae (19.1%), and Acinetobacter baumannii (11.4%). Extended-spectrum β- lactamases (ESBL(+)) strains were isolated in 38.5% of cases. Gram-positive bacteria comprised 28.6% (n = 60): The most common strains were enterococci (85% including HLAR 80.4% and VRE 17.6%] and staphylococci 11.8% [MRSA/MRCNS; 100%]. There were 19 (9%) fungal strains.

Conclusions

In general, the identification in urine samples of multi-drug-resistant bacterial and fungal strains in patients after OLT such as ESBL(+) 38.5%; HLAR 80.4%; VRE 17.6%; and MRSA/MRCNS 100% requires better infection control.     

Late cytomegalovirus disease following liver transplantation

The widespread use of antiviral prophylaxis or preemptive therapy among orthotopic liver transplantation (OLT) recipients has reduced the occurrence of early cytomegalovirus (CMV) disease. Late disease is increasingly reported. Little is known about CMV disease occurring beyond the first year after transplantation. The aim of this study was to evaluate the occurrence of CMV disease two or more years after OLT and to determine its risk factors and clinical features. Eighty-one consecutive OLT recipients followed for 2 years or longer after transplantation were included in the study. Data were collected on demographic and clinical variables, clinical presentation, treatment, and outcome of late CMV disease. Late CMV disease occurred in 7/81 liver recipients (8.5%) at a mean time of 5.9 years after OLT (range: 3.5--9.3, median: 6.3 years). All seven patients were women, with a mean age of 47.7 years (range: 26--60, median: 59 years). There was no association between the development of late CMV disease and the occurrence of rejection episodes, treatment with corticosteroids, or the early use of antiviral prophylaxis. Clinical presentation included fever and disturbed liver functions in all patients, one patient had concurrent CMV pneumonitis and one CMV retinitis. Though all patients responded to ganciclovir, two had recurrent disease episodes and one patient died of secondary bacterial sepsis. Late-onset CMV disease can occur several years after OLT. Although it manifests classic clinical features of early disease, it is not associated with traditional risk factors and its pathogenesis may differ from that of early disease.     

Surveillance of Bacterial and Fungal Infections in the Postoperative Period Following Liver Transplantation: A Series From 2005–2011

Orthotopic liver transplantation (OLT) is a life-saving procedure for the treatment of many end-stage diseases, but infectious and acute rejection episodes remain major causes of morbidity and mortality. Bacterial and fungal infections can be due to intra-abdominal, biliary, respiratory, urinary, wound, central venous catheters (CVC) or unknown sources. Using the computerized database of our microbiology laboratory, we analyzed all the bacterial and fungal infections in the first three months following OLT among 151 consecutive adult recipients at single center between January 2005 and December 2011. Samples included blood, bile CVC, urine, and bronchoalveolar lavage (BAL) specimen. Culture and identification of the isolated microorganisms was done in accordance with standard microbiological procedures. Three hundred thirteen samples from the above sites showed positive results for gram-positive cocci (n = 137; 43.8%), gram-negative rods (n = 156; 49.8%), and Candida species (n = 19; 6.1%). One patient (0.3%) experienced a CVC-related infection caused by Fusarium oxysporum. Bacterial and particularly biliary tract infections seem to play major roles in morbidity and mortality in the first three months following OLT. The major contributors to patient morbidity and mortality were candidemia and/or invasive candidiasis mainly from the biliary tract and/or CVC-related infections.     

Decreased survival in liver transplant patients requiring chronic dialysis: a Canadian experience

BACKGROUND: Chronic kidney disease is associated with increased mortality among nonrenal organ transplant recipients. End-stage renal disease (ESRD) is a serious complication after orthotopic liver transplantation (OLT). It is unclear if the outcomes of these individuals are different from nontransplant patients requiring dialysis or a kidney transplant. METHODS: We report the incidence of ESRD in OLT recipients and compare their outcomes to matched dialysis controls. We analyzed 4186 patients who received an OLT in Canada between January 1981 and December 2002 and 228 matched, nontransplant, chronic dialysis controls. RESULTS: The incidence of ESRD after OLT was 2.9% (n=120). The unadjusted mortality rate for those who required chronic dialysis was 49.2% compared with 26.8% in those who did not develop kidney failure (P<0.0001). The survival of OLT recipients on dialysis was lower than the matched chronic dialysis cohort (log-rank test, P=0.01). A kidney transplant was performed in 24% of the OLT recipients and 21% of the matched dialysis cohort, and their overall survival was similar. The OLT patients who remained on dialysis had a significantly lower survival when compared with matched dialysis patients who did not receive a kidney transplant (log-rank test, P=0.0002). CONCLUSIONS: Mortality was greater for OLT recipients on dialysis than would be expected from a matched, nontransplant, dialysis cohort. Kidney transplantation may abrogate some of this increased mortality risk.     

Significance of a T-lymphocytotoxic crossmatch in liver and combined liver-kidney transplantation

BACKGROUND: In contrast to kidney transplants a positive crossmatch is no contraindication for liver transplantation (OLT). In liver transplantation, antibody mediated rejections are rarely reported and a liver graft is suspected to have protective effects for kidney grafts when transplanted simultaneously. The aim of this study was to evaluate the effect of a positive crossmatch on outcome after OLT and combined liver and kidney transplantation (CLKTx). METHODS: We analyzed retrospectively the impact of a positive crossmatch on graft survival and rejection episodes after OLT (793pats) and CLKTx (18pats, 2.2%). Immunosuppression consisted of either Cyclosporine- or Tacrolimus-based regimens. RESULTS: A total of 50/811 (6%) of patients had a positive crossmatch, 45/793 (5.6%) with liver transplantation alone and 5/18 (28%) of patients with CLKTx. Follow-up ranged from 1 to 122.5 months (median 45.8 months). One- and 5-year graft survival rates of liver transplants alone with a positive crossmatch were 89.6% and 75.3%, respectively and were 88% and 77.5% in crossmatch negative recipients. Additionally, the incidence of acute and steroid-resistant rejection (44% and 15.5%) was not significantly increased in patients with a positive crossmatch when compared with patients with a negative crossmatch (38% and 19%). None of the patients with a positive crossmatch and CLKTx underwent a hyperacute-rejection episode after transplantation, and kidney graft survival 100%. CONCLUSIONS: In conclusion, a positive crossmatch is no contraindication for OLT and CLKTx. Furthermore, not having to wait for results of donor/recipient crossmatching can shorten cold ischemia time and may improve the clinical outcome.