First-hit SETBP1 mutations cause a myeloproliferative disorder with bone marrow fibrosis

ABSTRACT

SETBP1 mutations are found in various clonal myeloid disorders. However, it is unclear whether they can initiate leukemia, because SETBP1 mutations typically appear as later events during oncogenesis. To answer this question, we generated a mouse model expressing mutated SETBP1 in hematopoietic tissue: this model showed profound alterations in the differentiation program of hematopoietic progenitors and developed a myeloid neoplasm with megakaryocytic dysplasia, splenomegaly, and bone marrow fibrosis, prompting us to investigate SETBP1 mutations in a cohort of 36 triple-negative primary myelofibrosis (TN-PMF) cases. We identified 2 distinct subgroups, one carrying SETBP1 mutations and the other completely devoid of somatic variants. Clinically, a striking difference in disease aggressiveness was noted, with patients with SETBP1 mutation showing a much worse clinical course. In contrast to myelodysplastic/myeloproliferative neoplasms, in which SETBP1 mutations are mostly found as a late clonal event, single-cell clonal hierarchy reconstruction in 3 patients with TN-PMF from our cohort revealed SETBP1 to be a very early event, suggesting that the phenotype of the different SETBP1+ disorders may be shaped by the opposite hierarchy of the same clonal SETBP1 variants.

Evaluating the performance of large language models in haematopoietic stem cell transplantation decision-making

In a first-of-its-kind study, we assessed the capabilities of large language models (LLMs) in making complex decisions in haematopoietic stem cell transplantation. The evaluation was conducted not only for Generative Pre-trained Transformer 4 (GPT-4) but also conducted on other artificial intelligence models: PaLm 2 and Llama-2. Using detailed haematological histories that include both clinical, molecular and donor data, we conducted a triple-blind survey to compare LLMs to haematology residents. We found that residents significantly outperformed LLMs (p = 0.02), particularly in transplant eligibility assessment (p = 0.01). Our triple-blind methodology aimed to mitigate potential biases in evaluating LLMs and revealed both their promise and limitations in deciphering complex haematological clinical scenarios.

Idiopathic erythrocytosis: a germline disease?

Polycythemia Vera (PV) is typically caused by V617F or exon 12 JAK2 mutations. Little is known about Polycythemia cases where no JAK2 variants can be detected, and no other causes identified. This condition is defined as idiopathic erythrocytosis (IE). We evaluated clinical-laboratory parameters of a cohort of 56 IE patients and we determined their molecular profile at diagnosis with paired blood/buccal-DNA exome-sequencing coupled with a high-depth targeted OncoPanel to identify a possible underling germline or somatic cause. We demonstrated that most of our cohort (40/56: 71.4%) showed no evidence of clonal hematopoiesis, suggesting that IE is, in large part, a germline disorder. We identified 20 low mutation burden somatic variants (Variant allelic fraction, VAF, < 10%) in only 14 (25%) patients, principally involving DNMT3A and TET2. Only 2 patients presented high mutation burden somatic variants, involving DNMT3A, TET2, ASXL1 and WT1. We identified recurrent germline variants in 42 (75%) patients occurring mainly in JAK/STAT, Hypoxia and Iron metabolism pathways, among them: JAK3-V722I and HIF1A-P582S; a high fraction of patients (48.2%) resulted also mutated in homeostatic iron regulatory gene HFE-H63D or C282Y. By generating cellular models, we showed that JAK3-V722I causes activation of the JAK-STAT5 axis and upregulation of EPAS1/HIF2A, while HIF1A-P582S causes suppression of hepcidin mRNA synthesis, suggesting a major role for these variants in the onset of IE.

ALK inhibitors increase ALK expression and sensitize neuroblastoma cells to ALK.CAR-T cells

Selection of the best tumor antigen is critical for the therapeutic success of chimeric antigen receptor (CAR) T cells in hematologic malignancies and solid tumors. The anaplastic lymphoma kinase (ALK) receptor is expressed by most neuroblastomas while virtually absent in most normal tissues. ALK is an oncogenic driver in neuroblastoma and ALK inhibitors show promising clinical activity. Here, we describe the development of ALK.CAR-T cells that show potent efficacy in monotherapy against neuroblastoma with high ALK expression without toxicity. For neuroblastoma with low ALK expression, combination with ALK inhibitors specifically potentiates ALK.CAR-T cells but not GD2.CAR-T cells. Mechanistically, ALK inhibitors impair tumor growth and upregulate the expression of ALK, thereby facilitating the activity of ALK.CAR-T cells against neuroblastoma. Thus, while neither ALK inhibitors nor ALK.CAR-T cells will likely be sufficient as monotherapy in neuroblastoma with low ALK density, their combination specifically enhances therapeutic efficacy.

Effects of blocking CD24 and CD47 'don't eat me' signals in combination with rituximab in mantle-cell lymphoma and chronic lymphocytic leukaemia

Mantle-cell lymphoma (MCL) is a B-cell non-Hodgkin Lymphoma (NHL) with a poor prognosis, at high risk of relapse after conventional treatment. MCL-associated tumour microenvironment (TME) is characterized by M2-like tumour-associated macrophages (TAMs), able to interact with cancer cells, providing tumour survival and resistance to immuno-chemotherapy. Likewise, monocyte-derived nurse-like cells (NLCs) present M2-like profile and provide proliferation signals to chronic lymphocytic leukaemia (CLL), a B-cell malignancy sharing with MCL some biological and phenotypic features. Antibodies against TAMs targeted CD47, a 'don't eat me' signal (DEMs) able to quench phagocytosis by TAMs within TME, with clinical effectiveness when combined with Rituximab in pretreated NHL. Recently, CD24 was found as valid DEMs in solid cancer. Since CD24 is expressed during B-cell differentiation, we investigated and identified consistent CD24 in MCL, CLL and primary human samples. Phagocytosis increased when M2-like macrophages were co-cultured with cancer cells, particularly in the case of paired DEMs blockade (i.e. anti-CD24 + anti-CD47) combined with Rituximab. Similarly, unstimulated CLL patients-derived NLCs provided increased phagocytosis when DEMs blockade occurred. Since high levels of CD24 were associated with worse survival in both MCL and CLL, anti-CD24-induced phagocytosis could be considered for future clinical use, particularly in association with other agents such as Rituximab.

Evolutionary signatures of human cancers revealed via genomic analysis of over 35,000 patients

Recurring sequences of genomic alterations occurring across patients can highlight repeated evolutionary processes with significant implications for predicting cancer progression. Leveraging the ever-increasing availability of cancer omics data, here we unveil cancer's evolutionary signatures tied to distinct disease outcomes, representing "favored trajectories" of acquisition of driver mutations detected in patients with similar prognosis. We present a framework named ASCETIC (Agony-baSed Cancer EvoluTion InferenCe) to extract such signatures from sequencing experiments generated by different technologies such as bulk and single-cell sequencing data. We apply ASCETIC to (i) single-cell data from 146 myeloid malignancy patients and bulk sequencing from 366 acute myeloid leukemia patients, (ii) multi-region sequencing from 100 early-stage lung cancer patients, (iii) exome/genome data from 10,000+ Pan-Cancer Atlas samples, and (iv) targeted sequencing from 25,000+ MSK-MET metastatic patients, revealing subtype-specific single-nucleotide variant signatures associated with distinct prognostic clusters. Validations on several datasets underscore the robustness and generalizability of the extracted signatures.

Characterization of SARS-CoV-2 Mutational Signatures from 1.5+ Million Raw Sequencing Samples

We present a large-scale analysis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) substitutions, considering 1,585,456 high-quality raw sequencing samples, aimed at investigating the existence and quantifying the effect of mutational processes causing mutations in SARS-CoV-2 genomes when interacting with the human host. As a result, we confirmed the presence of three well-differentiated mutational processes likely ruled by reactive oxygen species (ROS), apolipoprotein B editing complex (APOBEC), and adenosine deaminase acting on RNA (ADAR). We then evaluated the activity of these mutational processes in different continental groups, showing that some samples from Africa present a significantly higher number of substitutions, most likely due to higher APOBEC activity. We finally analyzed the activity of mutational processes across different SARS-CoV-2 variants, and we found a significantly lower number of mutations attributable to APOBEC activity in samples assigned to the Omicron variant.

Humoral and cellular immune response in patients with hematological disorders after two doses of BNT162b2 mRNA COVID-19 vaccine: A single-center prospective observational study (NCT05074706)

Hematological patients at higher risk of severe COVID-19 were excluded from the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine trials. In this single-center observational prospective study (NCT05074706), we evaluate immune response in the hematological patients followed at the Hematological Division of San Gerardo Hospital, Monza (Italy) deemed to be severely immunosuppressed after vaccination with two doses of the BNT162b2 vaccine. Anti-SARS-CoV-2 immunoglobulin G titers above the cutoff value of 33.8 BAU/ml were detected in 303 (80.2%) out of the 378 patients enrolled. Patients with lymphoproliferative disorders had a significant lower probability of immunization (43.2% vs. 88.4%, p < 0.001). Patients treated with anti-CD20 showed a significantly lower probability of immunization compared to all other treatments (21.4%, p < 0.0001). Among 69 patients who failed seroconversion, 15 patients (22.7%) showed a positive T-cell response. Patients previously treated with anti-CD20 were 2.4 times more likely to test positive for T-cell responses (p = 0.014). Within a follow-up of 9 months from the second COVID-19 vaccination, symptomatic SARS-CoV-2 infections were reported by 20 patients (5.3%) and four of them required hospitalization. Successful serological or T-cell-mediated immunization conferred protection from symptomatic COVID-19. Patients treated with anti-CD20 who were not seroconverted after vaccination might still be protected from COVID-19 due to the T-cell immune response.

Tyrosine Kinase Inhibitor discontinuation in Chronic Myeloid Leukemia: eligibility criteria and predictors of success

TKI discontinuation proved to be safe and feasible in patients with CML with deep and durable molecular responses, introducing an additional treatment goal for these patients beyond overall survival. However, treatment interruption is a safe procedure only with appropriate patient selection and monitoring. Clinical and biological factors associated with better outcomes do not yet offer a precise stratification of patients according to their risk of relapse. This article aims at reviewing the leading studies present in the field in order to define eligibility criteria for discontinuation and predictors of success.

Abstract 1544: Generation of ALK CAR-T cells for neuroblastoma therapy

Neuroblastoma (NB) is the most deadly cancer in children with dismal survival in high-risk patients. The majority of NB express the full length anaplastic lymphoma kinase (ALK) receptor, that typically acts as driver oncogene together with MYCN. In contrast to ALK-driven lung cancer or lymphoma, targeted therapies with ALK tyrosine kinase inhibitors (TKIs), despite encouraging, induce only partial responses in NB. Therefore, additional tools to improve NB treatment are strongly needed. To specifically target NB cells, we developed a series of ALK chimeric antigen receptor (CAR) T constructs from antibodies that recognize both human and mouse ALK. Murine ALK CAR-T cells are able to control the growth of ALK+ leukemia and NB in syngeneic tumor models without detectable toxicity. From the leading candidate, we generated fully humanized ALK CAR-T cells that showed potent in vitro killing activity against a large panel of human NB lines, with activity comparable to GD2 CAR-T cells that are currently in clinical trials for NB patients. Remarkably, ALK CAR-T treatment synergized in vivo with the ALK inhibitor lorlatinib. Mechanistically, lorlatinib not only reduced tumor growth, but enhanced ALK expression on the surface of tumor cells, thereby facilitating ALK CAR-T targeting. Combination of ALK CAR-T cells with lorlatinib resulted in enhanced killing of NB cells and cure or markedly increased survival in mouse models of human metastatic NB even with low ALK expression. These findings support the clinical development of ALK CAR-T cells for NB therapy.

Citation Format: Elisa Bergaggio, Wei-Tien Tai, Andrea Aroldi, Ineês Mota, Diego Alvarado, Elisa Landoni, Jasna Metovic, Manuel Nüesch, Rafael Blasco-Patiño, Mauro Papotti, Gianpietro Dotti, Roberto Chiarle. Generation of ALK CAR-T cells for neuroblastoma therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1544.

Integrated Genomic, Functional, and Prognostic Characterization of Atypical Chronic Myeloid Leukemia

Supplemental Digital Content is available for this article.

Atypical chronic myeloid leukemia (aCML) is a BCR-ABL1-negative clonal disorder, which belongs to the myelodysplastic/myeloproliferative group. This disease is characterized by recurrent somatic mutations in SETBP1, ASXL1 and ETNK1 genes, as well as high genetic heterogeneity, thus posing a great therapeutic challenge. To provide a comprehensive genomic characterization of aCML we applied a high-throughput sequencing strategy to 43 aCML samples, including both whole-exome and RNA-sequencing data. Our dataset identifies ASXL1, SETBP1, and ETNK1 as the most frequently mutated genes with a total of 43.2%, 29.7 and 16.2%, respectively. We characterized the clonal architecture of 7 aCML patients by means of colony assays and targeted resequencing. The results indicate that ETNK1 variants occur early in the clonal evolution history of aCML, while SETBP1 mutations often represent a late event. The presence of actionable mutations conferred both ex vivo and in vivo sensitivity to specific inhibitors with evidence of strong in vitro synergism in case of multiple targeting. In one patient, a clinical response was obtained. Stratification based on RNA-sequencing identified two different populations in terms of overall survival, and differential gene expression analysis identified 38 significantly overexpressed genes in the worse outcome group. Three genes correctly classified patients for overall survival.

Chronic myeloid leukemia: Second-line drugs of choice

The efficacy of second-line treatment for chronic myeloid leukemia (CML) plays an important role in allowing CML patients to enjoy a normal life expectancy. Four tyrosine kinase inhibitors (TKIs) are presently available: bosutinib, dasatinib, nilotinib, ponatinib. Each one has different safety and activity profiles, which are reviewed here. No controlled studies are available to guide treatment decision, which must be based on the characterization of leukemic cells, especially in cases of resistance to TKI, coupled with the safety profile of each TKI. Patient comorbidities also play an important role in the treatment decision, which can achieve a new durable response in over 50% of treated patients.

Neurological symptoms in essential thrombocythemia: impact of JAK2V617F mutation and response to therapy

Patients with essential thrombocythemia (ET) often suffer from neurological symptoms (NS) not ever resulting from previous thrombotic cerebral events (TCE). We reported NS occurred in 282 patients, in order to identify the factors influencing ET-related NS in the absence of TCE, and the response to therapy. Overall, 116 of 282 patients (41%) presented NS; 101 of them (87%) reported subjective transient and fluctuating NS, without concurrent TCE, which we defined as ET-related NS, by frequency: cephalalgia, chronic paresthesias, dizziness or hypotension, visual disturbances, and tinnitus. In univariate analysis, ET-related NS resulted more frequently in young people (P = 0.017) and in females (P = 0.025). We found a higher prevalence of JAK2V617F mutation in ET-related NS patients (P = 0.021). In multivariate analysis, gender (P = 0.024) and JAK2V617F mutation (P = 0.041) remained significantly associated with the development of ET-related NS, with a risk of about four times higher for JAK2V617F-mutated patients (OR = 3.75). Ninety-seven of 101 patients with ET-related NS received an antiplatelet (AP) agent at the time of NS, whereas only selected high-risk ET-related NS patients were treated with a cytoreductive drug, according to the published guidelines and similarly to patients without NS. We observed that only 32 of 97 (33%) patients with ET-related NS achieved a complete response after AP treatment. Among the 65 non-responder patients, 36 (55.4%) improved NS after the introduction of cytoreductive therapy; therefore, the addition of cytoreductive treatment should be considered in this setting.

Natural History of Hepatitis C Virus Infection in Adult Renal Graft Recipients

AIM

To study the natural history of hepatitis C virus infection in renal transplantation, 464 HbsAg negative patients were prospectively studied from 1989.

METHODS

AntiHCV was tested by ELISA II and HCVRNA by Amplicor HCV RNA tests.

RESULTS

Two hundred nine patients were antiHCV positive (C+). HCVRNA was confirmed in 89% of C+ patients. Compared with the 255 anti-HCV negative (C-), C+ had undergone longer periods of dialysis (P = .0001), were more transfused (P = .01), and included more retransplants (P = .002). Immunosuppression was azathioprine (AZA) plus steroids in 133 and cyclosporine (CsA) in 331 patients. Liver biopsy showed chronic active hepatitis in 50, cirrhosis in 8, and fibrosing cholestatic hepatitis in 2 patients. Histologic progression of liver disease was confirmed in 18 of 26 patients. The causes of death in 84 patients (51 C+ vs 33 C-) were cardiovascular disease in 49%, sepsis in 13%, liver failure in 14%, neoplasia in 21%, and hepatocarcinoma in 2%. The 14-year patient survival was 75% in C+ and 86% in C- (P = .002). By multivariate analysis, age (>40) (P = .001) and C+ (P = .019) correlated with a worse patient survival. If patients were stratified according to age (<40 vs > or =40), younger C+ patients had a lower survival probability (P = .03). The 14-year graft survival was 44% in C+ vs 60% in C- patients (P = .001) but pure graft survival was similar (68% in C+ vs 72% in C-) (P = .13).

CONCLUSION

The presence of C+ significantly reduced both patient and graft survival in the long-term with liver failure being the second most frequent cause of death.

Risk factors associated to kidney stones in primary hyperparathyroidism

Nephrolithiasis is the most important clinical manifestation of primary hyperparathyroidism (PHPT), although nowadays this disorder is often asymptomatic. Clinical or biochemical differences between PHPT patients with and without nephrolithiasis have not been clearly identified in most of the previous studies. The aim of the study was to investigate clinical and biochemical parameters in kidney stone former (SF) and non-stone former (NSF) patients with PHPT in order to identify potential risk factors. Serum and plasma samples from 55 consecutive patients (43 females, 12 males) with PHPT were collected after overnight fasting; 24-h urine collection and a fresh sample of urine for sediment analysis were obtained from all patients. Clinical data were recorded in all. Out of 55 patients, 22 had kidney stones, which were symptomatic in 73%. SFs showed circulating PTH, total and ionized calcium, 1,25 dihydroxyvitamin D3, urinary calcium excretion and 24-h urine oxalate levels significantly higher than NSFs. Hypercalciuria was often concomitant with massive quantities of calcium oxalate crystals in urine sediment. Hypercalciuria and relatively high oxaluria were associated with stone formation with an odds ratio (OR) of 4.0 and 7.0, respectively, which rose to 33.5 when they coexisted. Hypomagnesuria and hypocitraturia were common in at least one third of all PHPT patients, but they were not associated to an increased OR. As expected, they were positively correlated with urine calcium excretion, suggesting that calcium, magnesium and citrate are commonly regulated at renal level. In conclusion, hypercalciuria, higher oxalate excretion and severe PHPT are associated with kidney stones in PHPT.

[Hepatitis C virus and renal transplantation]

Liver disease has emerged as an important cause of morbidity and mortality after renal transplantation (RT). Hepatitis C virus (HCV) is the leading cause of liver disease after RT. The impact of HCV infection on patient and graft survival is currently a major concern. Retrospective studies with appropriate follow-up have mainly demonstrated that HCV positive patients have greater mortality compared to HCV negative recipients after RT. Novel investigations by large databases (United States Renal Data Systems (USRDS)) have shown that recipients of donor HCV-positive kidneys are at an independently increased risk of mortality, adjusted hazard ratio 2.12 (95% confidence interval (95% CI), 1.72-2.87, p<0.001); there was no evidence that any subgroup was less affected. With appropriate informed consent, the use of a renal graft from an HCV positive donor could be offered to an HCV infected recipient. Many renal transplant candidates have satisfactory virological responses to antiviral therapy; the persistence of HCV clearance over a prolonged follow-up after RT has been recently noted. Further prospective studies are needed to define better the course of HCV infection among renal allograft recipients.

[Bone complications of renal transplantation. How to identify and prevent them]

Bone disease is a very frequent complication after renal transplantation (RTx). The main features of transplant bone disease include the osteopenic-osteoporotic syndrome, often complicated by fractures, avascular osteonecrosis of bones, bone pain syndrome and growth retardation in the children. The bone loss is greater during the first 12 months after RTx and can reach the osteoporotic range in above 40% of patients, with a fracture rate of 2-3% per year. The story of bone disease over the long pre-uremic and uremic period is one of the main causal factors. After RTx, glucocorticoid therapy seems to play the major causal role. Much more disputed is the role of the other immunosuppressive drugs, of persistent secondary hyperparathyroidism, and age. Hypophosphatemia and some genetic factors could also affect bone loss after RTx. Diabetic patients are particularly prone to develop bone disease after RTx. The main prophylactic interventions consist in the optimal control of hyperparathyroidism during the pre-transplant period, prescribing parathyroidectomy for autonomous hyperparathyroidism, not-responding to medical therapy. After RTx, both bisphosphonate and vitamin D metabolites, variably associated with calcium supplementation, have been demonstrated to have some beneficial effect on bone loss, at least in the first year after RTx. However, there are no data about the possible efficacy of these treatments on fracture rate.

From cyclosporine to the future

Most of the experience acquired in our unit with cyclosporine (CsA) comes from randomized trials. A first trial demonstrated that CsA-treated patients had a better 10-year graft survival than azathioprine-treated patients. A second trial showed equivalence between double therapy with CsA plus steroids and triple therapy with CsA, steroids, and azatioprine. A third trial showed similar 2-year graft survival with CsA monotherapy and triple therapy. A larger multicenter study that compared three different CsA-based regimens showed similar long-term graft survival with monotherapy, double therapy, and triple therapy. However, patients given monotherapy had less frequent steroid-related side-effects. Finally a more recent multicenter international trial showed that the rate of acute rejection can be reduced without increasing side effects by adding the monoclonal antibody basiliximab to the triple therapy. By reviewing our cumulative experience with CsA we found a mean graft half-life of 18.7 years for cadaver renal transplant recipients and 31.9 for the living transplant recipients. No significant attrition of graft function was found for patients with grafts functioning at 15 years. Two important issues with the present immunosuppression concern the long-term nephrotoxicity of calcineurin inhibitors and the cardiovascular disease, which is at least in part related to the use of steroids. To face these problems, we are currently involved in two multicenter trials, one comparing sirolimus plus mycophenolate mofetil to sirolimus plus low-dose CsA, while the other trial compares certican plus CsA to certican plus CsA plus corticosteroids.

Design of a trial comparing sirolimus plus mycophenolate mofetil versus sirolimus plus cyclosporine

We present the study design of a prospective, multicenter, randomized trial aimed at comparing the effects of two different combinations of sirolimus. Renal transplant recipients will be allocated to receive either sirolimus and mycophenolate mofetil (group A) or sirolimus and cyclosporine (group B). The primary endpoint will be the graft function at 3, 6, 12, 24, 36, 48, and 60 months. A number of secondary endpoints will also be considered. To obtain a significant difference in the primary endpoint 180 patients will be enrolled.

High prevalence, low pathogenicity of hepatitis G virus in kidney transplant recipients

BACKGROUND

Prevalence and pathogenicity of hepatitis G virus infection in long-term renal transplant recipients, are not fully known.

AIM

To evaluate long-term impact of HGV infection on liver disease of renal transplanted patients.

PATIENTS AND METHODS

A total of 155 hepatitis B surface antigen negative kidney transplant recipients, followed for a mean of 11 years after renal transplantation, were studied. Of these 48 (31%) patients had persistently elevated serum aminotransferase values. Frozen serum samples were tested for HGV-RNA and HCV-RNA by nested reverse transcribed polymerase chain reaction, and for anti-hepatitis G virus and anti-hepatitis C virus by enzyme-linked immunosorbent assay Hepatitis C virus-RNA was typed by a line probe assay and quantified by a branched DNA signal amplification assay

RESULTS

Hepatitis G virus-RNA was detected in 37 (24%) patients and anti-hepatitis G virus in another 26 (17%). Seventy (45%) patients had serum anti-hepatitis C virus and 63 of these (90%) had serum hepatitis C virus-RNA. Hepatitis G virus-RNA positive and negative patients were similar in terms of age, sex, duration of dialysis, rate of transfusion, chronic liver disease, rate of hepatitis C virus infection and immunosuppressive therapy. Fifteen (41%) hepatitis G virus-RNA seropositive patients were hepatitis C virus co-infected. Hepatitis C virus-RNA levels were significantly lower in the 15 hepatitis C virus/hepatitis G virus co-infected patients than in the 48 patients with hepatitis C virus infection only (2.2 vs 10.8 MEq/ml, p = 0.02). Only 3 hepatitis G virus carriers had persistently elevated alanine aminotransferase compared to 29 hepatitis C virus carriers (14% vs 60%, p < 0.001), 10 patients co-infected with both hepatitis G virus and hepatitis C virus, and in 6 patients with neither infection (67% vs 8%, p < 0.001).

CONCLUSIONS

Hepatitis G virus infection is common among kidney transplant patients, it carries a low risk of chronic liver disease even in long-term follow-up. Low levels of hepatitis C virus-RNA found in hepatitis G virus carriers suggest an interaction between these two viruses in immunosuppressed patients.

Effect of increased arterial resistance index on long-term outcome of well-functioning kidney grafts

An abnormal vascular status is present in the transplanted kidney. To define whether vascular factors might influence kidney function of the graft, the renal volume, blood flow and vascular resistance of a group of healthy subjects were compared with those of a group of well functioning renal transplants by color Doppler ultrasonography. Sixty healthy subjects and 75 well functioning cadaver renal transplant recipients were compared by color Doppler ultrasonography. Subsequently, 15 couples of donors and recipients of a living related renal graft were compared to observe the differences between the two organs of the same subject in a different environment. The variables studied were: the diameters and the volume of the kidney, renal blood flow and renal resistance index (RI). The group of cadaver renal transplant patients showed higher mean blood pressure (P = 0.009), higher serum creatinine levels (P = 0.0001) and lower endogenous creatinine clearance (P < 0.0001) than healthy controls. The length (P < 0.00001) and volume (P < 0.001) of the kidneys of cadaver transplanted patients were significantly greater than those of healthy subjects, while the length and volume of the living donors kidneys were identical to those of the recipients. RI, measured on renal vessels, showed lower values in healthy subjects and in kidney donors than in transplanted patients (P < 0.00001). Well functioning transplanted kidneys showed increased renal arterial RI. This non-immunologic factor did not appear to be detrimental with renal function in time, at least until 50 months after successful grafting.

The clinical status of cadaveric renal transplant patients treated for 10 year with cyclosporine therapy

In this paper we assessed the clinical status of 150 cadaveric renal transplant patients who received cyclosporine without interruption for 10 yr. The mean creatinine clearance was 59.2 +/- 15.71 at 1 yr and 55.6 +/- 24.91 mL/min at 10 yr (p = 0.039). Patients were subdivided into four quartiles according to the mean creatinine clearance at 1 yr. The 14 patients with the lowest quartile showed a significant decrease of creatinine clearance from the 1st to 10th year (from 31.5 +/- 5.83 to 24.8 +/- 14.00 mL/min; p = 0.038) while no difference between the mean creatinine clearance at 1 and at 10 yr was found in the other three quartiles. At 10 yr, 84.6% patients needed antihypertensive therapy, a rate similar to that seen at 1 yr (81.4%). The mean plasma cholesterol (253 +/- 57.8 mg/dL) and triglyceride (197 +/- 113.1 mg/dL) at 10 yr were similar to those found at +/- yr (243 +/- 48.2 and 201 +/- 143.0 mg/dL, respectively). Most patients have a high degree of rehabilitation 10 yr after uninterrupted cyclosporine therapy and all patients but 3 were able to work.

Effects of three immunosuppressive regimens on vertebral bone density in renal transplant recipients: a prospective study

The influence of three different immunosuppressive regimens with cyclosporine (CsA) on the development of osteopenia in renal transplant patients was assessed. Fifty-three adults with first kidney transplants participated in a randomized trial to analyze the efficacy of three different immunosuppressive regimens: CsA alone (group 1), CsA plus steroids (group 2), and CsA plus steroids plus azathioprine (group 3). Lumbar spine bone mineral density was assessed by dual energy x-ray absorptiometry every 6 months for 18 months. The values for trabecular mass were expressed as bone mineral density and as a fraction of the standard deviation of the mean of the normal value for patient's sex and decade of age (Z-score). Statistical analysis was performed on Z-score and "Z-score change" (value after 6 months minus the basal value at transplantation). At the 18th month, the Z-score increased significantly in treatment group 1 without steroids (P=0.006) and decreased significantly in steroid-treated groups 2 (P<0.001) and 3 (P<0.001). Comparing the two genders, Z-score decreased less in premenopausal women than in men (P=0.018). "Z-score change" did not correlate with steroid dosage, was high in patients with high basal bone mineral density, and was directly associated with the duration of dialysis (P=0.008). In conclusion, premenopausal transplant recipients showed a lower decrease of lumbar bone mineral density than men. In transplant recipients given CsA with steroids, lumbar bone mineral density decreased significantly, while it increased significantly in patients given CsA alone.

Cancer incidence in 854 kidney transplant recipients from a single institution: comparison with normal population and with patients under dialytic treatment

In this retrospective historical study, we compared the incidences of malignancies observed among 854 renal transplant recipients (RT) with at least 1 yr of follow-up, with the incidences of neoplasias among patients under regular dialytic treatment (RDT) and a control population from Northern Italy. Cox's proportional hazard model was used in RT recipients in order to evaluate the prognostic factors related to the development of neoplasia. Seventy six out of 854 RT patients (8.9%) developed some malignant neoplasia: 46% of these 76 were cutaneous neoplasias including melanomas, and the remaining 54% non cutaneous cancers: 33% miscellaneous tumors (MT), mostly adenocarcinomas, 17% Kaposi's sarcomas (KS), 4% non-Hodgkin's lymphomas (NHL). Malignancies had a higher incidence (p < 0.01) among RT recipients than among control and RDT patients. However, MT were equally frequent among the three groups. RDT patients on the contrary, had similar incidence of neoplasias when compared to the control population, but showed a lower incidence of squamous cell carcinomas (SCC). The risk ratios (RR) for the most frequent neoplasias among RT recipients vs. control population were: 224.7 for KS, 7.4 for NHL, 6.2 for SCC, 5.7 for basal cell carcinomas (BCC), 4.0 for MT. The risk of developing a de novo neoplasia was of about 13% at 10 yr and of 34% at 20 yr. In RT recipients, Cox's proportional analysis showed that age > 40 at transplantation and male sex were the only risk factors associated with an increased incidence of neoplasias, while no difference was observed between conventional (azathioprine+methylprednisolone: Aza+MP) and CsA therapy or in CsA monotherapy vs. double or triple therapy. However, KS occurrence correlated both with CsA dose (RR 15.2 for monotherapy; 12.5 for double therapy; 2.98 for triple therapy) and with 10 or more i.v. methylprednisolone pulses for treatment of rejection (RR 5.2). We conclude that in our series CsA does not increase the risk for development of neoplasias, when compared to conventional immunosuppression.

Increased detection of antibody to hepatitis C virus in renal transplant patients by third-generation assays

To assess the sensitivity and specificity of third-generation assays for antibody to hepatitis C virus (anti-HCV), sera from 244 renal transplant patients (113 positive for anti-HCV enzyme-linked immunosorbent assay [ELISA]-2) were studied. Hepatitis C virus RNA was detected by a reverse-transcripted nested polymerase chain reaction. Antibody to HCV was detected by ELISA-3 in 108 (96%) ELISA-2-positive samples. Five (4%) ELISA-2-positive sera were negative by both ELISA-3 and polymerase chain reaction. In the anti-HCV-negative group, six (5%) additional cases were ELISA-3-positive; three of these were confirmed by recombinant immunoblot assay-3 (RIBA-3) and polymerase chain reaction. Recombinant immunoblot assay-3 was used to resolve 82 RIBA-2-indeterminate and three RIBA-2-negative sera. Using RIBA-3, 49 (60%) RIBA-2-indeterminate samples were positive, five (6%) ELISA-3-negative samples were negative, and 28 (34%) were remained indeterminate. Recombinant immunoblot assay-2-negative samples were indeterminate with RIBA-3. Hepatitis C virus RNA was detected in all RIBA-3-positive and 58% of the RIBA-3-indeterminate samples. Third-generation assays for anti-HCV are more sensitive and specific than second-generation assays in renal transplant patients.

A randomized trial comparing triple-drug and double-drug therapy in renal transplantation. Analysis at 7 years

This is the 7-year update of a randomized trial comparing triple (TT) and double (DT) immunosuppressive therapy in renal transplantation. At 7 years, patient survival rate was 85% in DT vs. 87% in TT (P = NS); graft survival rate was 73% in DT and 68% in TT (P = NS); pure graft survival was 86% in DT vs. 77% in TT (P = 0.096). The 7-year graft survival rate was 67% for cadaver graft recipients vs. 92% for living-related graft recipients (P = 0.044). No difference in the slopes of plasma creatinine between the two groups was observed. Ten DT and 13 TT patients changed their original therapy: statistical analysis, however, was carried out according to intention to treat. Both CsA levels and doses were significantly higher in DT than in TT group (P < 0.001) at any time point up to the 7th year. At univariate analysis, a living-related donor kidney (P = 0.044) and immediate recovery of renal function (P < 0.001) were the only two parameters associated with graft survival at 7 years. At multivariate analysis, only early graft function recovery was correlated with late graft survival (RR = 10.480). Thus, even in the longterm, there is no difference between DT and TT, either in patient or in graft survival: at the doses we used, TT had a lower prevalence of late side effects than DT, however, long-term pure graft survival was better, although not significantly, in DT than in TT. The possibility of a safe shift from one regimen to the other one makes the two treatments complementary rather than alternatives.