Infection complicating percutaneous liver biopsy in liver transplant recipients

Multiloculated Liver Abscess: A Complication of Endoscopic Ultrasound-Guided Liver Biopsy

Endoscopic ultrasound (EUS)-guided liver biopsy is gaining popularity for liver parenchymal sampling due to its detailed visualization of liver anatomy, precision in sampling, and the ability to combine liver biopsy with other endoscopic goals. In this study, we present a case involving an anatomically complex, immunocompromised patient who underwent EUS-guided liver biopsy. While the samples were sufficient and progressed the management of her autoimmune hepatitis, her course was complicated by a multiloculated liver abscess. EUS liver biopsy has an excellent safety profile, but a small risk of infection remains, especially in immunocompromised patients or those with preexisting biliary obstruction.

Prognostic value of protein biomarkers in liver transplantation: A systematic review

Liver transplantation is currently the preferred method for the treatment of advanced liver disease and early-stage hepatocellular carcinoma (HCC). Although advances in surgical techniques, immunosuppressive drugs and postoperative management have reduced the incidence of postoperative complications, how to effectively predict or diagnose postoperative complications earlier and reduce their incidence is still a clinical concern. We performed a comprehensive proteomics literature research to identified protein biomarkers in complications after liver transplantation. Seventeen studies met the inclusion criteria including ischemia reperfusion injury (IRI) (n = 4), acute rejection (AR) (n = 4), renal dysfunction (n = 4), HCC recurrence (n = 2), primary graft dysfunction (PGD) (n = 1), infection (n = 1), and liver fibrosis (n = 1). A total of 625 differentially expressed proteins (DEPs) have been reported between postoperative complications and controls, of which 63 have been validated by quantitative protein expression and 26 have been reported by at least two studies and showed consistently changes. The results of the bioinformation analysis show that the immune system, especially the innate immune system and cytokine signaling in immune system, is an important protein-mediated pathway that affects the prognosis of liver transplantation.

Variability in personal protective equipment in cross-sectional interventional abdominal radiology practices

Purpose

To determine institutional practice requirements for personal protective equipment (PPE) in cross-sectional interventional radiology (CSIR) procedures among a variety of radiology practices in the USA and Canada.

Methods

Members of the Society of Abdominal Radiology (SAR) CSIR Emerging Technology Commission (ETC) were sent an eight-question survey about what PPE they were required to use during common CSIR procedures: paracentesis, thoracentesis, thyroid fine needle aspiration (FNA), superficial lymph node biopsy, deep lymph node biopsy, solid organ biopsy, and ablation. Types of PPE evaluated were sterile gloves, surgical masks, gowns, surgical hats, eye shields, foot covers, and scrubs.

Results

26/38 surveys were completed by respondents at 20/22 (91%) institutions. The most common PPE was sterile gloves, required by 20/20 (100%) institutions for every procedure. The second most common PPE was masks, required by 14/20 (70%) institutions for superficial and deep procedures and 12/12 (100%) institutions for ablation. Scrubs, sterile gowns, eye shields, and surgical hats were required at nearly all institutions for ablation, whereas approximately half of institutions required their use for deep lymph node and solid organ biopsy. Compared with other types of PPE, required mask and eye shield use showed the greatest increase during the SARS-CoV-2 pandemic.

Conclusion

PPE use during common cross-sectional procedures is widely variable. Given the environmental and financial impact and lack of consensus practice, further studies examining the appropriate level of PPE are needed.

Graphical abstract

Ultrasonographically guided percutaneous transhepatic liver biopsy after pediatric liver transplantation

BACKGROUND

Complications associated with ultrasonographically guided percutaneous transhepatic liver biopsy (PTLB) after liver transplantation (LT) have been rarely reported, and there is no consensus about its safety. We retrospectively reviewed the safety and outcomes of PTLB after pediatric LT.

METHODS

Between January 2008 and December 2019, 8/1122 (0.71%) pediatric patients who underwent ultrasonographically guided PTLB after LT developed complications. The median age at PTLB was 7.8 years (range 0.1-17.9). Grafts included left lobe/left lateral segment in 1050 patients and others in 72. PTLB was performed using local anesthesia±sedation in 1028 patients and general anesthesia in 94.

RESULTS

Complications after PTLB included acute cholangitis in 3 patients, sepsis in 2, respiratory failure due to over-sedation in 1, subcapsular hematoma in 1, and intrahepatic arterioportal fistula in 1. The incidence of complications of PTLB in patients with biopsy alone and those with simultaneous interventions was 0.49% and 3.19%, respectively (p = .023). Patients who developed acute cholangitis, respiratory failure, subcapsular hematoma, and arterioportal fistula improved with non-operative management. Of two patients with sepsis, one underwent PTLB and percutaneous transhepatic portal vein balloon dilatation and developed fever and seizures the following day. Sepsis was treated with antibiotic therapy. Another patient who underwent PTLB and exchange of percutaneous transhepatic biliary drainage catheter developed fever and impaired consciousness immediately. Sepsis was treated with antibiotic therapy, mechanical ventilation, and continuous hemofiltration.

CONCLUSIONS

Percutaneous transhepatic liver biopsy after pediatric LT is safe. However, combining liver biopsy with simultaneous procedures for vascular and biliary complications is associated with an increased risk of complications.

Sepsis Following Liver Biopsy in a Liver Transplant Recipient: Case Report and Review of Literature

Percutaneous liver biopsy is a relatively safe procedure with low complication rates. Infections following liver biopsy are uncommon and can lead to a poor outcome. There are limited data on liver biopsy-related infections among liver transplant (LT) recipients. Also, there is a paucity of data regarding the use of prophylactic antibiotics in LT patients undergoing percutaneous liver biopsy. We report a case of systemic sepsis following percutaneous liver biopsy in a LT recipient with choledochojejunal anastomosis. This was followed by severe rejection and deterioration of liver function and recurrence of primary sclerosing cholangitis (PSC) to the extent that he has been listed for retransplantation. This case report emphasizes the potential risk of sepsis in LT recipients with bilioenteric anastomosis undergoing percutaneous liver biopsy. This increased risk may warrant periprocedural broad spectrum antibiotic prophylaxis, in this subgroup of patients.

Prognostic value of endogenous and exogenous metabolites in liver transplantation

Liver transplantation has been widely accepted as an effective intervention for end-stage liver diseases and early hepatocellular carcinomas. However, a variety of postoperative complications and adverse reactions have baffled medical staff and patients. Currently, transplantation monitoring relies primarily on nonspecific biochemical tests, whereas diagnosis of multiple complications depends on invasive pathological examination. Therefore, a noninvasive monitoring method with high selectivity and specificity is desperately needed. This review summarized the potential of endogenous small-molecule metabolites as biomarkers for assessing graft function, ischemia-reperfusion injury and liver rejection. Exogenous metabolites, mainly those immunosuppressive agents with high intra- and inter-individual variability, were also discussed for transplantation monitoring.

Guidelines on the use of liver biopsy in clinical practice from the British Society of Gastroenterology, the Royal College of Radiologists and the Royal College of Pathology

Liver biopsy is required when clinically important information about the diagnosis, prognosis or management of a patient cannot be obtained by safer means, or for research purposes. There are several approaches to liver biopsy but predominantly percutaneous or transvenous approaches are used. A wide choice of needles is available and the approach and type of needle used will depend on the clinical state of the patient and local expertise but, for non-lesional biopsies, a 16-gauge needle is recommended. Many patients with liver disease will have abnormal laboratory coagulation tests or receive anticoagulation or antiplatelet medication. A greater understanding of the changes in haemostasis in liver disease allows for a more rational, evidence-based approach to peri-biopsy management. Overall, liver biopsy is safe but there is a small morbidity and a very small mortality so patients must be fully counselled. The specimen must be of sufficient size for histopathological interpretation. Communication with the histopathologist, with access to relevant clinical information and the results of other investigations, is essential for the generation of a clinically useful report.

Posttransplant biopsy risk for stable long-term pediatric liver transplant recipients: 451 percutaneous biopsies from two multicenter immunosuppression withdrawal trials

Although liver biopsy is the gold standard for assessing allograft health, its attendant risk has deterred its use in routine monitoring of stable liver transplant recipients during long-term follow-up. We utilized prospectively collected data on adverse events from 2 clinical trials of immunosuppression withdrawal to quantify the risk of liver biopsy in pediatric liver transplant recipients. The trials included 451 liver biopsies in 179 children. No biopsies led to bleeding requiring transfusion or intervention, suggesting a clinically significant bleeding risk of <0.8%. Complications were reported in 5.5% of biopsies (95% CI 3.6%-8.1%): 5.8% (21/363) of protocol biopsies and 4.5% (4/88) of for-cause biopsies (P = .80). Mild complications occurred in 1.8% of biopsies, moderate in 1.8%, and severe in 2.0%. The majority of complications (89%) resolved within 1 week. Six of 9 (67%) severe complications were related to biliary issues; 5 were episodes of cholangitis. Biopsy-related cholangitis occurred only in children with underlying biliary strictures. Overall, biopsy-related complications were infrequent and resolved quickly. Severe complications were rare, with occult biliary stricture as the dominant driver. Our study provides evidence for clinicians who are considering the risk vs benefit of surveillance liver biopsies in pediatric liver transplant recipients.

Liver biopsy-related infection in liver transplant recipients: A current matter of concern?

Data from published studies regarding risk factors for liver biopsy (LB)-related infectious complications in liver transplant recipients are inconsistent. We carried out a retrospective cohort study analyzing consecutive LBs for orthotopic liver transplant patients at a tertiary hospital (2001-2011): there were 667 LB procedures (575 percutaneous procedures and 92 transjugular procedures) in 286 liver transplant recipients. There were 20 complications in 19 patients (overall incidence = 3.0%): 10 were infectious complications (8 cases of bacteremia and 2 cases of peritonitis). The causal microorganisms were mainly Pseudomonas aeruginosa (4 patients) and Enterobacteriaceae (4 patients). All complications occurred with biopsies performed in patients hospitalized for more than 48 hours (381 biopsies for 201 patients); hence, only this group was included in the risk factor analysis. The variables associated with the development of infectious complications after LB were the presence of impaired biliary drainage at the time of biopsy (40% versus 15.1%, P = 0.03) and low albumin levels (2.4 versus 3.1 g/dL, P = 0.01). In conclusion, according to our experience, infectious complications secondary to LB in liver transplant recipients are related to hospitalization at the time of biopsy, particularly in the presence of impaired biliary drainage and low albumin levels.

Hepatic emphysema associated with ultrasound-guided liver biopsy in a dog

An eleven-year-old Chinese Crested Powder Puff dog presented with polydipsia/polyuria, inappetence, diarrhea and vomiting underwent an ultrasound-guided percutaneous liver biopsy. Two days post-biopsy the clinical condition of the dog acutely deteriorated with fever, dyspnea, ataxia and subcutaneous emphysema. Radiographs and ultrasound showed focal severe hepatic emphysema in the region of the previous liver biopsy. Post-mortem examination revealed chronic hepatitis with dissecting fibrosis, acute hepatitis with hemorrhage and in the hindlimb musculature extensive hemorrhage and necrosis. Pure cultures of the gas producing bacteria Clostridium perfringens were isolated in samples from the hind limb musculature. We propose that the hepatic emphysema in the region of the biopsy site was a result of a clostridial infection.

Strategies for the prevention of infection after solid organ transplantation

Infection is a frequent complication of organ transplantation and is associated with significant morbidity and mortality. Preventative antimicrobial strategies are a key component of the care received by transplant patients. This review summarizes the evidence supporting anti-infective prophylaxis in this setting. Specific recommendations for the prevention of bacterial, fungal, viral and parasitic infection after transplant are made, with a focus on recent developments in the field of transplant infectious diseases.

Test-retest repeatability of MR elastography for noninvasive liver fibrosis assessment in hepatitis C

PURPOSE

To conduct a rigorous evaluation of the repeatability of liver stiffness assessed by MR elastography (MRE) in healthy and hepatitis-C-infected subjects.

MATERIALS AND METHODS

A biopsy-correlated repeatability study using four-slice MRE was conducted in five healthy and four HCV-infected subjects. Subjects were scanned twice on day 1 and after 7-14 days. Each slice was acquired during a 14-s breath-hold with a commercially available acquisition technique (MR-Touch, GE Healthcare). Results were analyzed by two independent analysts.

RESULTS

The intraclass correlation coefficient (ICC) was 0.85 (90% confidence interval [CI]: 0.71 to 0.98) for the between-scan average of maximum stiffness within each slice and 0.88 (90% CI: 0.78 to 0.99) for the average of mean stiffness within each slice for the primary analyst. For both analysts, the average of the mean liver stiffness within each slice was highly reproducible with ICC of 0.93 and 0.94. Within-subject coefficients of variation ranged from 6.07% to 10.78% for HCV+ and healthy subjects.

CONCLUSION

MRE is a highly reproducible modality for assessing liver stiffness in HCV patients and healthy subjects and can discriminate between moderate fibrosis and healthy liver. MRE is a promising modality for noninvasive assessment of liver fibrosis (CLINICALTRIALS.GOV IDENTIFIER: NCT00896233).

Percutaneous liver biopsy after living donor liver transplantation resulting in fulminant hepatic failure: the first reported case of hepatic compartment syndrome

A 28-year-old female who underwent live donor liver transplantation 3 years prior presented after percutaneous liver biopsy with abdominal and shoulder pain, nausea, vomiting, and elevated liver enzymes. Computed tomography (CT) showed an intrahepatic and subcapsular hematoma. There was a progressive increase in liver enzymes, bilirubin, and INR and a decline in hemoglobin. Subsequent CT imaging revealed flattening of the portal vein consistent with compression by the enlarging hematoma. Liver failure ensued and the patient required urgent retransplantation. The explant demonstrated ischemic necrosis of greater than 90% of the liver parenchyma. We report this case of “Hepatic Compartment Syndrome” leading to fulminant hepatic failure.

Serial measurement of Doppler hepatic hemodynamic parameters for the diagnosis of acute rejection after live donor liver transplantation

To elucidate the role of Doppler hepatic hemodynamic parameters as surrogate markers of acute rejection (AR) after live donor liver transplantation (LDLT), serial Doppler measurements were prospectively performed during the first 2 weeks after LDLT to compare the longitudinal hepatic hemodynamic changes between patients with histologically proven AR and patients without histologically proven AR. Forty-six patients that had undergone adult-to-adult LDLT using a right lobe graft were enrolled in this study. The portal venous maximum velocity (PVV; cm/second), portal venous flow volume, hepatic arterial peak systolic velocity, hepatic arterial pulsatility index, hepatic venous maximum velocity, hepatic venous pulsatility index, and splenic arterial pulsatility index were measured. Fourteen patients were diagnosed by biopsy to have clinically relevant AR. Markedly increased PVV was seen soon after surgery and gradually decreased in both patients with clinically relevant AR and patients without clinically relevant AR. This serial change of decreasing PVV was significantly greater in patients with clinically relevant AR (P < 0.0001). After postoperative day 6, the PVV in patients with clinically relevant AR was significantly lower than that in patients without clinically relevant AR (PVV on postoperative day 6: 35.6 +/- 21.3 versus 58.3 +/- 27.1 cm/second, respectively, P = 0.0080). A PVV cutoff value of 20.2 cm/second demonstrated the best accuracy for predicting clinically relevant AR. The sensitivity and specificity for predicting clinically relevant AR were 92.9% and 87.1%, respectively. The area under the curve was 0.94. In conclusion, serial Doppler measurement of hepatic parameters in LDLT is useful for the diagnosis of clinically relevant AR. Clinically relevant AR should therefore be suspected when a marked unexpected decrease in the PVV is observed.

Safety and efficacy of sonographic-guided random real-time core needle biopsy of the liver

PURPOSE

To determine the safety and efficacy of real-time, sonographic-guided, random percutaneous needle biopsy of the liver in a tertiary medical center.

METHOD

From an IRB-approved biopsy database, all patients who had random liver biopsy performed over a 24-month period were selected. In 350 patients, 539 random percutaneous needle biopsies of the liver were performed under real-time sonographic visualization. The following were recorded from the electronic medical record: patient demographics, indication for biopsy procedure; radiologist's name; needle type and gauge and number of passes; use and amount of i.v. sedation or anesthesia; adequacy of the specimen; and complications following the procedure.

RESULT

Of 539 biopsies, 378 (70%) biopsy procedures were performed on liver transplant recipients. Of the biopsy procedures in nontransplant patients, 81/161 (50%) concurrently underwent biopsy of a focal liver mass. An 18-gauge automated core biopsy needle was used in 536/539 (99%). Median number of passes per biopsy procedure was 1 (mean, 1.7; range, 1-6). Sedation using midazolam and fentanyl was used in 483/539 (90%). There were only 8 inadequate specimens (1.5%, [2.3, upper 95% confidence limit, fully described in Statistical Analysis]). Complications were identified in 11/539 biopsy procedures (2.0%, [2.6, upper 95% confidence limit]): 5 with severe postprocedural pain, 3 with symptomatic hemorrhage, 2 with infection, and 1 with a rash. There were no sedation-related complications and no deaths related to the procedure.

CONCLUSION

Real-time, sonographic-guided, random core-needle liver biopsy is a safe and highly effective procedure.

Protocol liver allograft biopsies

Protocol liver allograft biopsies are liver biopsies carried out at specific time points according to predetermined guidelines, rather than in response to specific indications such as change in the patient's clinical status or biochemical tests. Use of protocol liver allograft biopsy has been declining over the last decade: an informal survey of 35 transplant units showed that whereas 65% of units undertake protocol biopsies for those grafted for Hepatitis C virus infection, only 25% do so for patients grafted for other indications. In this overview, we consider the arguments against and those in favor of liver biopsies in adult liver allograft recipients. Arguments against the use of protocol liver biopsies are that they biopsies put the patient are associated with a small risk of morbidity and mortality, are expensive, do not provide useful information and do not alter clinical practice. The estimated rate of major complications is 0.6% and the estimated mortality rate 0.02%. However, the argument in favor of protocol biopsies is that even when standard liver tests are normal, there is on-going inflammation in the graft which, if immunosuppression is not altered, will lead to progressive fibrosis, cirrhosis and even graft loss. Conversely, normal liver histology may allow for reduction in the immunosuppression and so lower the risk of the complications associated with immunosuppression. Currently available diagnostic techniques are not yet sufficiently sensitive or specific to provide an accurate reflection of the state of the graft and the presence or absence of graft damage. We conclude that, while there are no clear data showing that protocol liver allograft biopsies are cost effective and lead to improved patient and graft outcome, such biopsies still have a role in the management of the liver transplant recipient.

Histologic abnormalities are common in protocol liver allograft biopsies from patients with normal liver function tests

The utility of protocol liver allograft biopsies remains controversial, particularly in patients with normal liver function tests (LFTs). However, histologic evaluation of these biopsies provides an opportunity to examine the types and severity of liver diseases that can occur in livers with normal clinical and biochemical function. We studied 165 protocol allograft biopsies taken from 100 liver transplant patients at the time of normal LFTs and normal clinical function at 3 to 8 months (n=36), 1 year (n=52), 2 to 3 years (n=54), and 4 to 5 years (n=23). Biopsies were classified as normal, minimal changes (eg, nonaggressive portal or lobular mononuclear inflammation, steatosis <10%), fatty liver disease, recurrent primary liver disease, and transplant-related disease (portal-based rejection or central venulitis, an inflammatory pattern that encompasses perivenular hepatocyte dropout, mononuclear inflammation, pigment-laden macrophages, and variable zone 3 fibrosis). Among these 100 patients, a total of 394 protocol biopsies were performed, and 165 (42%) were taken at the time of normal LFTs and normal clinical function. One hundred twenty-one (73%) were normal or showed minimal/nonspecific changes. Forty-four (27%) showed histologic abnormalities that included fatty liver disease (n=19, nonalcoholic in 18 cases; 13 with mild steatosis, 6 with moderate steatosis, 7 with grade 1/3 steatohepatitic activity, and 2 with stage 1/4 steatohepatitic fibrosis), recurrent primary biliary cirrhosis (n=9; all stage 1/4), recurrent hepatitis C infection (n=6; grade 0/4 in 1, grade 1/4 in 5, stage 0/4 in 4, stage 1/4 in 1, and stage 2/4 in 1), recurrent sarcoidosis (n=1), Ito cell hyperplasia (n=4; marked in 2 and mild in 2), central venulitis (n=10; 5 with mild zone 3 fibrosis or central vein obliteration and 1 with central-portal bridging fibrosis), and mild acute portal rejection (n=2). We judged the histologic changes to be of clinical significance in 19 (11.5%) cases. These results indicate that even at the time of normal clinical and laboratory function, a significant fraction of protocol allograft biopsies harbor histologic (27%) and clinically significant (11.5%) abnormalities. These most commonly include fatty liver disease, low-grade/low-stage recurrent hepatitis C and primary biliary cirrhosis, and central venulitis (including some cases with subsequent fibrosis progression). The data support performance of protocol biopsies to assess allograft status, and provide insight into the types and severity of liver diseases that can smolder in transplanted (and by extension, probably also in native) livers with apparent normal function.

The clinical significance of early histological rejection with or without biochemical abnormality in adult living donor liver transplantation for hepatitis B virus related end stage liver disease

There is no agreement regarding the treatment of early allograft rejection (EAR) in adult living donor liver transplantation (LDLT). A protocol biopsy was performed in 62 adult LDLT recipients. Twenty-one patients (33.9%) had histological evidence of EAR. Of these, 14 patients had biochemical abnormalities and seven patients had no associated biochemical abnormalities. None of the seven patients with subclinical EAR (11.3% of the entire study population) were treated, and no subsequent rejection was observed. Gender mismatch (female-to-male) was the single independent risk factor for histological EAR [odds ratio (OR) = 13.458; 95% confidence interval (CI), 1.836-98.649] and the cumulative probability for a subsequent rejection was higher in patients with EAR (OR = 11.085; 95% CI, 1.221-100.654). However, the actuarial 1 year patient and graft survival rate in patients with EAR (81.0% and 85.5%) were similar to those without EAR (92.7% and 97.25%; P = 0.127 and 0.302, respectively). The presence of an initial biochemical abnormality was an independent risk factor for both a decreased patient survival (OR = 5.827; 95% CI, 1.095-31.017; P = 0.039) and graft loss (OR = 20.646; 95% CI, 2.044-208.524; P = 0.010). Subsequent rejection developed more frequently in patients with EAR. However, the survival is not determined by the presence of EAR but by the presence of a biochemical abnormality.

Subcapsular hematoma of the graft after liver transplantation

Subcapsular hematoma of the graft is an underreported complication of liver transplantation (LT). Among 408 LT performed from September 1, 1985, to September 1, 2000, eight patients developed a subcapsular hematoma within 30 days after LT (8/408 = 2.0%). Among the six early cases observed, five required further surgical approaches due to hematoma progression, rupture, and hemorrhage. One patient underwent liver retransplantation due to uncontrollable hepatic hemorrhage. The two more recent cases were successfully treated by early opening of the Glisson's capsule with hemostasis of the hepatic raw bleeding surface. The five patients who developed acute renal failure required dialysis. Three patients died during hospitalization. Among the survivors, two were discharged on the postoperative (PO) day 15; the others on PO day 37, 38, and 56. In conclusion, subcapsular hematoma of the graft is a potentially serious complication of LT that may produce severe hemorrhage, shock, and in extreme cases, graft loss or even death. The severity of the complication is related to the extension of the decapsulated area of the graft. An early surgical approach with intentional opening of the hematoma before progression of the lesion seems to facilitate hemostasis and improve results.

Controversies in liver biopsy: who, where, when, how, why?

Liver biopsy continues to have a central role in the evaluation of patients with suspected liver disease. The procedure is often indicated to evaluate otherwise unexplained liver biochemical test abnormalities, but the precise degree of serum aminotransferase elevations that should prompt a liver biopsy is controversial, as is the need for liver biopsy in all patients with suspected nonalcoholic fatty liver disease and chronic hepatitis C. Standard liver biopsy is contraindicated in patients with severe coagulopathy and ascites, although the degree of coagulopathy that contraindicates a liver biopsy is controversial. A transjugular approach is an alternative in patients with coagulopathy or ascites. Controversy surrounds all the technical aspects of liver biopsy, particularly the choice of needle (cutting vs suction) and the use of ultrasound to mark or guide the biopsy site. Bleeding is the major complication of liver biopsy, with a risk of 0.3%; cutting needles are more likely to cause hemorrhage than are suction needles. Traditionally, liver biopsy has been the province of the hepatologist/ gastroenterologist. However, an increasing number of liver biopsies are performed by radiologists. The implications of this trend with respect to patient outcome, safety, and training of fellows is unclear.

The natural history of acute histologic rejection without biochemical graft dysfunction in orthotopic liver transplantation: a systematic review

Protocol biopsy results in the first few weeks after liver transplantation sometimes display histologic features of acute cellular rejection (ACR), even in the absence of significant clinical or biochemical dysfunction. At present there is no clear consensus about the need to treat such cases with adjuvant immunosuppression. This systematic review describes, from the available evidence, the natural history of untreated histologic ACR in the absence of biochemical graft dysfunction. An electronic search of the Medline, Embase, and Cochrane Library databases was performed to select studies that reported protocol liver biopsies in the early posttransplant period from 1983 to 2000. Studies that identified patients with ACR on protocol biopsy who were not treated with adjuvant immunosuppression formed the basis of the study group. Data from individual studies were extracted using standardized pro forma and pooled for descriptive analysis. The search identified 3431 studies, of which 516 were cited in full. Of these, 15 studies met all of the inclusion criteria. These 15 studies reported on 1566 patients who had protocol biopsies performed in the early posttransplant period, of which 1048 (67%) had histologic evidence of ACR. Three hundred and thirty one (32%) patients with histologic ACR on protocol biopsy had no associated biochemical graft dysfunction. Without treatment, only 14% of these patients subsequently developed biochemical graft dysfunction requiring adjuvant immunosuppression. Steroid-resistant rejection and chronic rejection both had a prevalence of 4% in patients with untreated histologic ACR and no biochemical graft dysfunction. Withholding adjuvant immunosuppression from patients with histologic ACR and no biochemical graft dysfunction seems to be safe, as long as graft function is carefully monitored. The rationale for performing protocol biopsies in the absence of biochemical graft dysfunction is questionable.

Ultrasound-assisted percutaneous liver biopsy performed by a physician assistant

OBJECTIVE

Percutaneous liver biopsy is an essential diagnostic tool utilized in the management of patients with liver disease. This procedure is generally performed by a physician and has a small but well-defined complication rate. We report on the complication rate and efficiency of ultrasound-assisted percutaneous liver biopsy performed by an experienced physician assistant.

METHODS

One thousand eighty-six consecutive outpatient liver biopsies (847 hepatic allografts and 239 native livers) were performed at a single center by a physician assistant between June, 1996 and June, 2000. Patients with hepatic mass lesions, unusual hepatic anatomy, and uncorrectable coagulopathy (international normalized ratio > 1.7, platelet count < 50 x 10(9)/L) were excluded. Bedside ultrasonography was used to determine the optimal site for the liver biopsy. Liver biopsies were performed with a 15-gauge Jamshidi aspiration biopsy needle. Patients were observed for 3 h after biopsy, followed by dismissal with subsequent contact in 24 h to assess outcome and complications.

RESULTS

Adequate tissue was obtained in 1084 cases (99.8%), with a mean tissue length of 3.2 cm. After the procedure, narcotic analgesia was necessary in 116 (10%) of the patients undergoing liver biopsies. The overall complication rate requiring hospitalization was 0.6%. Major complications requiring intervention occurred in four patients (0.4%). There were no deaths resulting from liver biopsies.

CONCLUSION

We conclude that outpatient percutaneous liver biopsy can be safely and effectively performed by a trained physician assistant.

Hyperbilirubinemia and cholestatic liver injury in hepatitis C-infected liver transplant recipients

OBJECTIVE

A cholestatic pattern of liver injury has been observed in liver transplant recipients with rapidly progressive hepatitis C. We assessed the frequency and causes of cholestasis in hepatitis C-infected liver transplant patients, and evaluated the clinical and pathological course of those with cholestatic hepatitis C.

METHODS

Sixty-nine sequential liver transplant recipients who had detectable hepatitis C viremia were studied retrospectively. Records and diagnostic tests were examined from patients who developed hyperbilirubinemia.

RESULTS

Hyperbilirubinemia occurred in 33 of 69 (48%) hepatitis C-infected liver transplant patients. A thorough evaluation including review of clinical and laboratory data, ultrasound with Doppler, cholangiogram, and liver biopsy identified causes of hyperbilirubinemia other than hepatitis C in 26 of 33 patients. Seven patients developed cholestatic hepatitis C characterized by histological features of recurrent hepatitis C and cholestatic liver injury with ballooning of centrilobular hepatocytes, bile ductular proliferation, and canalicular cholestasis, in the absence of other causes of cholestasis. Five progressed rapidly to bridging fibrosis and two died of complications related to liver failure. Four patients with cholestatic hepatitis C showed extended survival after the onset of hyperbilirubinemia.

CONCLUSIONS

1) Hepatitis C is a relatively infrequent cause of cholestasis in liver transplant recipients. 2) The diagnosis of cholestatic hepatitis C requires a multimodality approach to exclude other causes of cholestasis. 3) Cholestatic hepatitis C ranges in severity and is not always associated with rapid development of graft failure, although significant histological abnormalities are frequent.

Prevention of infections in solid organ transplant recipients

Solid organ transplantation has become an important therapeutic option for multiple chronic diseases. With the advent of newer and potent immunosuppressive regimens, graft survival has improved, but at the expense of an increased risk for the development of infections secondary to bacterial, fungal, viral and parasitic pathogens. Prevention of such infectious complications with effective, well tolerated, and cost-effective anti-microbials would be ideal to improve the outcome of transplanted patients. However, the emergence of multi-drug resistant pathogens, medication toxicity and drug-drug interactions need to be carefully evaluated. This review summarizes the most relevant data pertaining to our current understanding of infection prevention for solid organ transplant recipients. Specific recommendations are given for the prevention of each group of microorganisms and types of solid organ transplant.