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Shimon Kusne

Publications and source records attributed to Shimon Kusne.

At least 19 recordsLinked to original sources

Viral and fungal infections after liver transplantation--part II.

Viral and fungal infections in liver transplant recipients are important to recognize and treat early because of their association with substantial morbidity and mortality. Some viruses, such as cytomegalovirus and human herpesvirus 6, have immunomodulatory properties and can facilitate other infections, including fungal infections. Cytomegalovirus has long been recognized as an important virus in transplantation, but in the past decade other viruses have also received attention in the medical literature because of their association with particular clinical syndromes. Although human herpesvirus 6 has been associated with fever, rash, and encephalitis, a direct cause-and-effect relationship is still lacking. Human herpesvirus 8 has been found to be the cause of Kaposi sarcoma. Molecular techniques (e.g., pp65 antigenemia and polymerase chain reaction) that have been introduced for routine diagnosis of viruses have facilitated the diagnosis of asymptomatic viral infections and the institution of preemptive therapy. Nonetheless, the diagnosis of invasive fungal infections in liver transplant recipients is often delayed and thus associated with high mortality. Despite the use of new antifungal agents in clinical practice and the reduced incidence of fungal infections because of antifungal prophylaxis regimens, mortality has not decreased. Future patient outcomes may improve with early identification of patients who have risk factors for invasive fungal infections and with the development of new molecular diagnostic techniques for early detection.

Adult↗

Molecular and clinical perspectives of polyomaviruses: emerging evidence of importance in non-kidney transplant populations.

JC virus (JCV), BK virus (BKV) and simian virus 40 (SV40) are deoxyribonucleic acid (DNA) viruses, members of the family Polyomaviridae. These viruses establish persistent infections, and reactivate from latency in their host under immunosuppression. During the last few years there has been recognition of the morbidity related to polyomaviruses, particularly BKV in kidney transplant recipients. More importantly, recent studies indicate the potential implication of JCV, BKV, and SV40 in renal dysfunction among nonrenal organ transplant patients. Polyomaviruses are tumor-inducing viruses and animal models have provided evidence of the oncogenicity of these pathogens. Although data are not conclusive, molecular studies suggest an association of BKV and SV40 with malignancies among solid organ transplant patients. As new and potent immunosuppressive agents are introduced into clinical practice, it is believed that the incidence of polyomavirus-related diseases in organ transplantation might increase. This review evaluates the biologic and epidemiologic features of these 3 viruses, the data regarding their infections in nonkidney organ transplant patients and describes future directions in the management and research of these opportunistic pathogens.

BK Virus↗

Transmission of rabies virus from an organ donor to four transplant recipients.

BACKGROUND: In 2004, four recipients of kidneys, a liver, and an arterial segment from a common organ donor died of encephalitis of an unknown cause. METHODS: We reviewed the medical records of the organ donor and the recipients. Blood, cerebrospinal fluid, and tissues from the recipients were tested with a variety of assays and pathological stains for numerous causes of encephalitis. Samples from the recipients were also inoculated into mice. RESULTS: The organ donor had been healthy before having a subarachnoid hemorrhage that led to his death. Encephalitis developed in all four recipients within 30 days after transplantation and was accompanied by rapid neurologic deterioration characterized by agitated delirium, seizures, respiratory failure, and coma. They died an average of 13 days after the onset of neurologic symptoms. Mice inoculated with samples from the affected patients became ill seven to eight days later, and electron microscopy of central nervous system (CNS) tissue demonstrated rhabdovirus particles. Rabies-specific immunohistochemical and direct fluorescence antibody staining demonstrated rabies virus in multiple tissues from all recipients. Cytoplasmic inclusions consistent with Negri bodies were seen in CNS tissue from all recipients. Antibodies against rabies virus were present in three of the four recipients and the donor. The donor had told others of being bitten by a bat. CONCLUSIONS: This report documenting the transmission of rabies virus from an organ donor to multiple recipients underscores the challenges of preventing and detecting transmission of unusual pathogens through transplantation.

Adult↗

Prospective assessment of Platelia Aspergillus galactomannan antigen for the diagnosis of invasive aspergillosis in lung transplant recipients.

The clinical utility of Platelia trade mark Aspergillus galactomannan antigen for the early diagnosis of invasive aspergillosis was prospectively assessed in 70 consecutive lung transplant recipients. Sera were collected twice weekly and tested for galactomannan. Invasive aspergillosis was documented in 17.1% (12/70) of the patients. Using the generalized estimating equation model, at the cutoff value of >or= 0.5, the sensitivity of the test was 30%, specificity 93% with positive and negative likelihood ratios of 4.2 and 0.75, respectively. Increasing the cutoff value to >or= 0.66 yielded a sensitivity of 30%, specificity of 95%, and positive and negative likelihood ratios of 5.5 and 0.74. A total of 14 patients had false-positive tests, including nine who had cystic fibrosis or chronic obstructive pulmonary disease. False-positive tests occurred within 3 days of transplantation in 43% (6/14) of the patients, and within 7 days in 64% (9/14). Thus, the test demonstrated excellent specificity, but a low sensitivity for the diagnosis of aspergillosis in this patient population. Patients with cystic fibrosis or chronic obstructive pulmonary disease may transiently have a positive test in the early post-transplant period.

Adult↗

Efficacy of galactomannan antigen in the Platelia Aspergillus enzyme immunoassay for diagnosis of invasive aspergillosis in liver transplant recipients.

The utility of galactomannan antigen for diagnosing invasive aspergillosis was evaluated in 154 liver transplant recipients. Sample agreement was 98.5%, and patient specificity was 87%. Galactomannan positivity correlated with mortality, even when controlled for the number of tests performed. Whether galactomannan positivity identifies a subgroup at risk for poor outcome warrants further evaluation.

Adult↗

Use of parenteral colistin for the treatment of serious infection due to antimicrobial-resistant Pseudomonas aeruginosa.

Serious infection due to strains of Pseudomonas aeruginosa that exhibit resistance to all common antipseudomonal antimicrobials increasingly is a serious problem. Colistin was used as salvage therapy for 23 critically ill patients with multidrug-resistant P. aeruginosa infection. Twenty-two patients who had septic shock (n=14) and/or renal failure (n=21) received mechanical ventilatory support at baseline. The most common types of infection were pneumonia (n=18) and intra-abdominal infection (n=5). Colistin was administered for a median of 17 days (range, 7-36 days). Seven patients died during therapy, at a median of 17 days (range, 4-26 days) after initiation of treatment. A favorable clinical response was observed in 14 patients (61%); only 3 patients experienced relapse. Bacteremia was the only significant factor associated with treatment failure (P=.02). One patient manifested diffuse weakness that resolved after temporary cessation of colistin therapy. Colistin provides an important salvage therapeutic option for patients with otherwise untreatable serious P. aeruginosa infection.

Adult↗

Opportunistic mycelial fungal infections in organ transplant recipients: emerging importance of non-Aspergillus mycelial fungi.

To determine the spectrum and impact of mycelial fungal infections, particularly those due to non-Aspergillus molds, 53 liver and heart transplant recipients with invasive mycelial infections were prospectively identified in a multicenter study. Invasive mycelial infections were due to Aspergillus species in 69.8% of patients, to non-Aspergillus hyalohyphomycetes in 9.4%, to phaeohyphomycetes in 9.4%, to zygomycetes in 5.7%, and to other causes in 5.7%. Infections due to mycelial fungi other than Aspergillus species were significantly more likely to be associated with disseminated (P=.005) and central nervous system (P=.07) infection than were those due to Aspergillus species. Overall mortality at 90 days was 54.7%. The associated mortality rate was 100% for zygomycosis, 80% for non-Aspergillus hyalohyphomycosis, 54% for aspergillosis, and 20% for phaeohyphomycosis. Thus, non-Aspergillus molds have emerged as significant pathogens in organ transplant recipients. These molds are more likely to be associated with disseminated infections and to be associated with poorer outcomes than is aspergillosis.

Adolescent↗

Changes in the spectrum and risk factors for invasive candidiasis in liver transplant recipients: prospective, multicenter, case-controlled study.

BACKGROUND: This study determines whether the spectrum, risk factors, and outcome of invasive candidiasis in liver transplant recipients have changed. METHODS: Thirty-five consecutive liver transplant recipients with invasive candidiasis were prospectively studied in a case-controlled, multicenter study. One control was matched with the case for duration of hospitalization and the other for antibiotic use so that risk factors unique in liver transplantation could be elicited. RESULTS: In matched-pair analysis, antibiotic prophylaxis for spontaneous bacterial peritonitis (odds ratio [OR] 8.3, P=0.002), posttransplant dialysis (OR 7.6, P=0.0009), and retransplantation (OR 16.4, P=0.0018) were independently significant predictors of invasive candidiasis. Candida spp. included C. albicans in 65% of patients, C. glabrata in 21%, C. tropicalis in 9%, C. parapsilosis in 3%, and C. guilliermondii in 3%. Patients with C. albicans infections were less likely to have received antifungal prophylaxis than those with non-albicans Candida infections (13.6% vs. 50%, P=0.04). The mortality rate was 36.1% for the cases and 2.8% for the controls (OR 25.0, 95% confidence interval, 6.2-100.5, P=0.0002). Non-albicans Candida infections (P=0.04) and prior antifungal prophylaxis (P=0.05) correlated with poorer outcome in the cases. CONCLUSIONS: Our study has identified predictors for Candida infections in the current era that have implications relevant for targeting the prophylaxis toward the high-risk patients. Routine use of antifungal prophylaxis warrants concern given the emergence of non-albicans Candida spp. as significant pathogens after liver transplantation and higher mortality in patients with these infections.

Anti-Bacterial Agents↗

Invasive aspergillosis in liver transplant recipients: outcome comparison of therapy with amphotericin B lipid complex and a historical cohort treated with conventional amphotericin B.

Invasive aspergillosis (IA) in liver transplant recipients is associated with poor response rates and a very high mortality rate, despite administration of therapy with conventional amphotericin B. We conducted a single-center, retrospective study to compare the outcome of liver transplant recipients with IA who received amphotericin B lipid complex (ABLC) or conventional amphotericin B. IA was present in 12 ABLC-treated patients (definite, 4; probable, 8) and 29 amphotericin B recipients (definite, 11; probable, 18) in the historical cohort. The 60-day mortality rate was lower in the ABLC cohort: 4 (33%) of 12 patients versus 24 (83%) of 29 patients (P=.006). Only 1 of 4 ABLC recipients with definite IA died, compared with all 11 in the amphotericin B group. Sixty-day survival probability curves was significantly lower in the amphotericin B cohort (P=.008). ABLC therapy was the only independent mortality-protective variable (odds ratio, 0.31; 95% confidence interval, 0.07-0.44; P=.02). First-line or early salvage therapy for IA with ABLC was associated with significantly improved survival relative to a comparable historical group treated with amphotericin B.

Amphotericin B↗

Longitudinal study of cryptococcosis in adult solid-organ transplant recipients.

While studies in kidney recipients have found meningitis to be the most common clinical manifestation of cryptococcosis (Cry), it is unclear if the clinical presentation of Cry differs among various solid-organ transplant (SOT) recipients and whether the serum cryptococcal antigen (SCA) might predict the site of infection. We report the clinical manifestations and the correlation with a positive SCA among 55 consecutive SOT recipients diagnosed with Cry at the University of Pittsburgh Medical Center. These included: heart (n=13), lung (n=4), liver (n=28), kidney (n=9) and small bowel (n=1) recipients. While there were no significant differences in the manifestations of Cry in heart and lung recipients, kidney recipients had disseminated disease as the most common presentation (P=0.02). In contrast, pneumonia (P=0.003) and meningitis (P=0.02) were more frequent than disseminated disease in liver recipients. Positive SCA was higher in patients with disseminated disease and meningitis than in patients with isolated pneumonia (P=0.0001). Significant differences in the manifestations of Cry were observed among types of SOT populations. A positive SCA may be predictive of dissemination and meningitis, but it may not be sensitive for pulmonary disease.

Adult↗

LVAD bloodstream infections: therapeutic rationale for transplantation after LVAD infection.

INTRODUCTION: Patients who have ventricular assist devices (VADs) and experience bloodstream infection (BSI) have high mortality. We addressed 2 questions raised by the United Network for Organ Sharing (UNOS) priority policy for this problem: 1) Are organs wasted on this ultra-high-risk group? 2) Can device-related BSI be differentiated from transient BSI? METHODS: Patients with VADs who underwent heart transplantation from 1987 to 2001, who had BSI during VAD support, and who had positive cultures at VAD explant (device-related BSI, n = 10) were compared with those with negative cultures at explant (non-device-related BSI, n = 11). RESULTS: Patients with device-related BSI had an 80% (8/10) rate of persistent bacteremia; 30 days and 1 year after transplantation, mortality was 14% and 26%, respectively. Non-device-related BSI (n = 11) persisted in 18% (2/11); peri-operative and 1-year mortalities were 9% and 13%. Duration of VAD support predicted infection (132 vs 48 days, p < 0.001); hypo-albuminemia (2.9 +/- 0.5 mg/dl vs 3.3 +/- 0.8 mg/dl, p < 0.05), and a resistant organism predicted a device-related BSI. These patients had increased intubation requirements and had increased creatinine concentration during the first post-operative week, with no difference in liver function, blood loss, transfusions (packed red blood cells, fresh frozen plasma, or platelets), or hemodynamic stability vs patients with non-device BSI. Despite decreased immunosuppression, we found no difference in acute rejection events with device-related BSI. Re-infection with the pre-operative organism occurred in only 1 patient per group. CONCLUSIONS: These data suggest that urgent (Status 1A) cardiac transplantation is effective in stable patients with device-related BSI, and these data support the current UNOS policy. However, an extra-device source of BSI should be excluded by considering the isolated organism, the baseline nutritional status, and other risk factors.

Bacteremia↗

Parainfluenza virus infection in adult lung transplant recipients: an emergent clinical syndrome with implications on allograft function.

Parainfluenza virus is a common cause of seasonal upper respiratory tract infections in children and adults. Studies indicate that parainfluenza virus may play an important role in the etiology of respiratory tract infections in lung transplant recipients with an estimated incidence of 5.3 per 100 patients. Parainfluenza virus type 3 is the most frequent serotype in lung transplant patients. The rate of lower respiratory tract infections with parainfluenza virus among lung transplant recipients is between 10 and 66% of cases. In addition, trans-bronchial biopsy at the time of parainfluenza infection shows signs of acute allograft rejection. Subsequently, 32% of patients have been found to have active bronchiolitis obliterans at a median time of 6 months (range 1-14) postviral infection. These findings indicate that parainfluenza virus infections may have long-term implications for lung transplant recipients. Further studies are required to identify the mechanisms of immunomodulation of parainfluenza virus among these patients. In addition, controlled studies are needed to evaluate the efficacy of aerosolized ribavarin in the treatment of parainfluenza virus infection and to determine whether vaccines may be effective in these high-risk patients.

Administration, Inhalation↗

Infectious etiology of bronchiolitis obliterans: the respiratory viruses connection - myth or reality?

A variety of viruses, such as the influenza viruses A and B, the human respiratory syncytial virus, the parainfluenza viruses, and the adenoviruses, cause seasonal respiratory tract infections in young children and adults. Also, studies indicate that these viruses are an important group of pathogens in pediatric and adult lung transplant recipients. More importantly, accumulating data on these infections among lung transplant patients suggest that these illnesses may have immediate and long-term implications for the function of the transplanted lung, including the development of bronchiolitis obliterans. This is important because patient survival and allograft function in lung transplantation remain limited by the development of bronchiolitis obliterans. Models of lung transplantation indicate that respiratory viral infections cause acute and chronic airway damage after transplantation. The mechanism leading to allograft damage by respiratory viruses may be related to the production of alloreactive cytokines such as interleukin (IL)-1, tumor necrosis factor, IL-6 and IL-8 during viral replication. Current clinical data are suggestive of a possible role for respiratory viruses in the development of bronchiolitis obliterans, but further control studies are required to evaluate the significance of respiratory virus infections as a causal factor in the development of bronchiolitis obliterans in lung transplantation.

Bronchiolitis Obliterans↗

Trends in risk profiles for and mortality associated with invasive aspergillosis among liver transplant recipients.

To discern whether the characteristics and outcome of invasive aspergillosis in liver transplant recipients have evolved during the past decade, 26 patients who underwent transplantation during 1990-1995 (known as "the earlier cohort") were compared with 20 patients who underwent transplantation during 1998-2001 (known as "the later cohort"). Twenty-three percent of the Aspergillus infections in the earlier cohort occurred > or =90 days after transplantation, compared with 55% of such infections in the later cohort (P=.026). The earlier cohort was significantly more likely to have disseminated infection (P=.034) and central nervous system (CNS) involvement (P=.0004) than was the later cohort. The mortality rate was significantly higher for the earlier cohort (92%) than for the later cohort (60%; P=.012). Only disseminated infection (not the year of transplantation) approached statistical significance as an independent predictor of outcome. In the current era, invasive aspergillosis occurs later in the posttransplantation period, is less likely to be associated with CNS infection, and is associated with a lower mortality rate, compared with invasive aspergillosis in the early 1990s.

Adolescent↗

Pathogenesis and management of polyomavirus infection in transplant recipients.

Polyomaviruses (JC virus [JCV], BK virus [BKV], and simian virus 40 [SV40]) establish subclinical and persistent infections and share the capacity for reactivation from latency in their host under immunosuppression. JCV establishes latency mainly in the kidney, and its reactivation results in the development of progressive multifocal leukoencephalopathy. BKV causes infection in the kidney and the urinary tract, and its activation causes a number of disorders, including nephropathy and hemorrhagic cystitis. Recent studies have reported SV40 in the allografts of children who received renal transplants and in the urine, blood, and kidneys of adults with focal segmental glomerulosclerosis, which is a cause of end-stage renal disease and an indication for kidney transplantation. Clinical syndromes related to polyomavirus infection are summarized in the present review, and strategies for the management of patients who receive transplants are discussed.

Cystitis↗