Tacrolimus Therapeutic Drug Monitoring in Stable Kidney Transplantation and Individuation of CYP3A5 Genotype.

The posology of tacrolimus (TAC) is usually guided by its therapeutic drug monitoring. Some patients reach target concentrations (CTs) quickly, others more slowly. In a retrospective study, 20 kidney transplant recipients were included (mean age, 50.7 ± 14.1 years; weight 64.0 ± 14.2 kg; patients clinically stable for over a year). We studied cytochrome CYP3A5 genotype, in particular CYP3A5 6986A>G, the most important polymorphism related to the metabolism of TAC (wild genotype CYP3A5 *1 genotype, and CYP3A5 *3 variants). One year after transplantation, the CTs were 5.0 to 8.0 ng/mL. The patients were divided into group A (TAC doses < 6.0 mg/d) and group B (TAC doses > 6.0 mg/d). All were tested for the CYP3A5 gene sequence to characterize their polymorphism. Patients with CYP3A5 *1/*1 and *1/*3 were extensive metabolizers, and those with CYP3A5 *3/*3 were poor metabolizers. In group A and group B, the average TAC doses at the time of therapeutic drug monitoring were 3.0 ± 1.4 ng/mL (0.05 ± 0.03 mg/kg) and 12.8 ± 3.7 ng/mL (0.2 ± 0.1 mg/kg), respectively (P < .001). Group A was the poor metabolizers genotype, while in group B, the extensive metabolizers genotype was present. Patients with the CYP3A5 *1/*1 or *1/*3 genotype required 1.5 to 2 times higher doses than patients *3/*3 to reach CT. This genetic test allows clinicians to know, before the kidney transplant, the patient's TAC metabolism pattern and then to optimize the drug exposure.

Kidney Transplantation in Elderly Recipients: A Single-Center Experience.

In this retrospective single-center study we evaluated the outcome after kidney transplant in recipients older than 65 years in terms of patient and graft survival and causes of death. PATIENTS AND METHODS: From 1993 to 2016, 109 consecutive first single kidney transplants in recipients older than 65 years were included. Furthermore, 2 age groups have also been identified (group A, 65-70 years old vs group B, 71-76 years old). Donor and recipient characteristics were analyzed. Other parameters were cold and warm ischemia times, delayed graft function, biopsy-proven acute rejection, and causes of death. Induction immunosuppressive therapy was performed with basiliximab or thymoglobulin. Baseline triple immunosuppression included calcineurin inhibitor, antimetabolite, and steroids. The results of preimplantation biopsies, which were performed in all expanded criteria donors were analyzed and graded according to Karpinski 2009 classification. RESULTS: Overall mortality was 39.4%: 23.2% women and 76.8% men. Causes of death were infections in 42%, tumors in 23%, cardiovascular disease in 14%, cerebrovascular disease in 7%, and unknown in 14%. The most common cause of death in men was infections (52%), and the most common cause in women was tumors (55%). At 1, 3, 5, and 10 years, overall patient survival was 89%, 84%, 72%, and 45%, and overall graft survival was 100%, 97%, 89%, and 84%, respectively. Patient and graft survival were statistically different between group A vs group B (P = .006 and P = .02, respectively). At univariate analysis significant risk factors for increased mortality were age, delayed graft function, and cold ischemia time. At multivariate analysis, delayed graft function maintained statistical significance. CONCLUSIONS: Kidney transplantation in patients older than 65 years is safe, feasible, and has good graft survival. Mortality is statistically significant in patients older than 71 years, despite a persistent low graft loss.

De Novo Solid Tumors After Kidney Transplantation: Is It Time for a Patient-Tailored Risk Assessment? Experience From a Single Center.

BACKGROUND: Progress in immunosuppressive therapy and perioperative techniques has improved the survivals of both grafts and patients. The patient, however, is exposed to the risks of aging and side effects of immunosuppression. De novo tumors are the 2nd cause of death in the organ transplant population. The aim of this study was to evaluate whether the current accepted guidelines for the pre-transplantation study and the post-transplantation follow-up have been effective, in our kidney transplant population, regarding early detection and treatment, improving prognosis, and reducing mortality of some curable neoplastic diseases. METHODS: We considered de novo tumors in kidney transplant patients from 1995 to 2010 (n = 636) excluding hematologic and nonmelanoma skin tumors from our study. RESULTS: There were 64 de novo tumors in 59 patients out of 636 kidney transplant patients; 29.68% were urogenital cancer, 26.56% gastrointestinal cancer, 12.5% melanoma, 6.25% lung cancer, 6.25% biliopancreatic cancer, 4.68% visceral Kaposi sarcoma, 4.68% breast cancer, 4.68% thyroid cancer, 1 pleural mesothelioma, 1 meningioma, 1 merkeloma. Twenty patients died because of cancer. Ten patients had a late de novo tumor diagnosis, when the stage of tumor was advanced and not suitable for curative treatment. CONCLUSIONS: Because of the increased neoplastic risk, we consider it mandatory to carry out a meticulous screening and to implement pre-transplantation study concerning this increased neoplastic risk population to detect a subgroup of patients presenting the highest risk to improve their outcome.

Preemptive liver-kidney transplantation in von Gierke disease: a case report.

Type 1a glycogen storage disease (GSD 1a), or von Gierke disease, is a rare, autosomal-recessive disease caused by a deficiency of glucose-6-phosphatase, which leads to glycogen accumulation in the liver, kidney, and intestinal mucosa. Clinical manifestations include hypoglycemia, growth retardation, hepatomegaly, lactic acidemia, hyperlipidemia, and hyperuricemia. Long-term complications include renal disease, gout, osteoporosis, pulmonary hypertension, short stature, and hepatocellular adenomas, which may undergo malignant transformation. Herein we have described the management and the clinical course of a GSD1a patient who underwent simultaneous preemptive liver- kidney transplantation (SPLKT), which solved the liver and renal disease. We confirmed the rapid normalization of glucose metabolism, and correction of hyperlipemia after liver transplantation. In our opinion uremic patients with GSD 1a with or without adenomas must be considered for SPLKT. To our knowledge this is the fifth case of SPLKT and the first preemptive one to be described in the literature.

[Uretero-vescical anastomosis during kidney transplantation. Preliminary results of two surgical techniques]. / L'anastomosi uretero-vescicale nel trapianto di rene. Risultati preliminari di due tecniche a confronto.

AIM: The most frequent urologic complications after renal transplantation involve the uretero-vescical anastomosis (leakage, stenosis, and reflux), with a frequency of 1% to 30% in different series. METHODS: We present our results in a prospective randomized trial performed from October 2004 to September 2005, in a cohort of 36 patients, who underwent renal transplantation from cadaveric donor at our institution. A uretero-vescical anastomosis according to Lich-Gregoir was used in 18 cases (group A), whereas an anastomosis according to Knechtle was performed in other 18 patients (group B), respectively. The groups were comparable for donors and recipients characteristics. The mean donor age was 46.3 years vs 44.9 years, and the mean duration of cold ischemia was 1 086+/-296 min vs 1 100+/-381 min for group A and for group B respectively. The mean recipient age was 47.5 years vs 46.1 for group A and group B, respectively. RESULTS: No differences were evidenced between the two uretero-vescical anastomosis in term of surgical complications, infections or patient and graft survival at one year of follow-up. Stenosis and leakage involved 2 patients for each group respectively. Numbers of infections, days of antibiotic therapy were similar between the two groups. CONCLUSION: Our early experience does not evidence differences between the two types of uretero-vescical anastomosis.

Intraperitoneal Tenckhoff catheter for the treatment of recurrent lymphoceles after kidney transplantation: our early experience.

Lymphoceles may occur as frequently as 16% of the time after kidney transplantation, becoming clinically evident between 18 and 180 days after surgery. The management of lymphoceles is unclear. Percutaneous needle aspiration and external drainage are associated with high recurrence and complications. Surgical intraperitoneal marsupialization of lymphocele is considered the treatment of choice, but requires hospital admission, general anesthesia, and sometimes extensive surgical dissection. We discuss our experience in the treatment of recurrent symptomatic lymphocele intraperitoneally drained using a Tenckhoff catheter in 7 consecutive patients. Clinical manifestations became evident between 26 and 90 days after transplantation. The diagnosis was obtained with abdominal ultrasound in all cases; mean lymphocele diameter was 14 +/- 6 cm. After percutaneous drainage, performed to differentiate urinoma/lymphocele and to rule out infections, the lymphocele recurred within 1 month. Thereafter, we decided to treat recurrent lymphatic collection using a Tenckhoff catheter. The lymphocele was located during the operative procedure using a sterile 3.5-MHz ultrasound probe. With the patient under local anesthesia, we performed 2 vertical 1-cm incisions to the lymphocele and peritoneum, respectively. The Tenckoff catheter was first positioned into the lymphocele and the tunneled inside the peritoneal cavity. One cuff of the Tenckhoff was fixed to the fascia to avoid possible delocalization. The patients were discharged the same day. The catheter was removed 6 months later with no evidence of lymphocele recurrence.

De novo malignancies after kidney and liver transplantations: experience on 582 consecutive cases.

De novo malignancies after transplantation are a growing problem of solid organ transplant recipients, due to longer survival follow-up under chronic immunosuppression. The aim of this study was to analyze a population of 582 consecutive kidney (n = 382) and liver (n = 202) transplant recipients, who survived at least 12 months after transplantation, at a single transplant center for the development of de novo cancers. The incidence of de novo malignancies was 7% after both renal and liver transplantation. The median elapsed time from transplant to the diagnosis of de novo malignancy was 45 months (range 3 to 220) months for kidney and 37 months (range 12 to 101 months) for liver transplants. Skin cancers were the most common within renal recipients, while gastroenteric cancers were more frequently encountered in liver transplants. Oropharyngeal and upper digestive tract tumors were always associated with a history of chronic alcohol consumption in liver recipients. Liver transplant recipients treated for acute rejection had a worse cancer prognosis than patients without rejection 1- and 2-year survivals 83% and 63% versus 36% and 17% (P = .026). The estimated 1- and 2-year survival rates for all types of de novo malignancies were 79% and 66%, including 64% and 51% for solid organ tumors versus 89% and 89% for skin cancers and posttransplant lymphoproliferative disorder (PTLD) (P = .17) in renal transplants and 70% and 42%, including 57% and 28% for solid organ tumors versus 85% and 64% for skin cancers and PTLD (P = .43) in liver transplants respectively.

Effects of successful renal transplantation on left ventricular mass.

Left ventricular hypertrophy is an independent cardiovascular risk factor in the general population and in patients with chronic renal failure. Relatively little is known about the effects of renal transplantation on left ventricular hypertrophy. The aim of this study was to determine the changes in left ventricular mass after successful renal transplantation and to evaluate the importance of some clinical, laboratory, and echocardiographic variables on the trend to left ventricular hypertrophy. Twenty-three patients with end-stage renal disease were studied by ambulatory blood pressure monitoring and echocardiography before and 2 years following renal transplantation. After 24 months of follow-up, all transplant recipients had adequate renal function (serum creatinine <2 mg/dL). At the end of the study, we observed a significant decrease in left ventricular mass and left ventricular mass index compared to the pretransplantation period. In renal transplant recipients, the prevalence of left ventricular hypertrophy significantly decreased (78% versus 44%, P < .03) after 2 years of follow-up. Systolic 24-hour blood pressure was the only predictor of left ventricular mass and of left ventricular mass index at 2 years after transplantation. In conclusion, successful renal transplantation produces a regression of left ventricular hypertrophy. This beneficial effect depends on a decrease in systolic pressure levels.

Renoprotective effect of early inhibition of the renin-angiotensin system in renal transplant recipients.

The aim of this work was to study the effect of early administration of angiotensin-converting enzyme inhibitors (ACEI) and angiotensin II type-I receptors blockers (ARB) on renal function and proteinuria in renal transplant recipients with good, stable renal function and mild proteinuria. Twenty four patients started ACEI/ARB therapy within 14 months after surgery (RAS-). Before (T0) and every month for 2 years after the initiation of ACEI/ARB we evaluated creatinine clearance (CrCl), proteinuria/day (UP), UP/CrCl (FUP), arterial blood pressure, and serum lipid levels. Twenty-eight patients who never received ACEI/ARB (RAS+) were studied in the same fashion. In the RAS+ CrCl was reduced after 2 years compared with T0 (64.5 +/- 2.6 vs 75.0 +/- 3.2 mL/min, P < .003); UP and FUP were both significantly increased (666 +/- 65 vs 132 +/- 20 mg/day 8.8 +/- 1.2 vs 2.6 +/- 0.6 mg/mL x 10(3); P < .001 and .002) compared with T0. Moreover, UP (P < .04), FUP (P < .03), and the percentage reduction of CrCl (11.4% +/- 5% vs 4.6% +/- 1.8%; P < .05) were greater in RAS+ than RAS- subjects at 2 years of the study. The values of other parameters did not show significant differences between the two groups. In conclusion, this study suggested that ACEI/ARB have renoprotective effects, when used in patients with good stable renal function and mild proteinuria. These drugs may play a role to prevent chronic allograft nephropathy.

Renal transplantation in a patient affected by Mounier-Kuhn syndrome.

Tracheobronchomegaly, also called Mounier-Kuhn syndrome, consists in dilatation of the trachea and major bronchi because of atrophy or absence of their elastic fibers and smooth muscle cells. Standard chest radiography often does not permit diagnosis because only lateral imaging, obtained with X-rays or chest CT scan, shows the true degree of tracheal dilatation. Surgery has no role in tracheomegaly, except for the complications of tracheal stenosis or pneumothorax. The present work reports cadaveric renal transplantation in a 43-year-old woman affected by end-stage renal disease and suffering from congenital tracheobronchomegaly diagnosed during the first decade of life. No surgical or anesthetic problems were encountered during the immediate perioperative period. The patient did not require pulmonary physiotherapy. Antibiotic prophylaxis was given for 10 days. No pulmonary infection developed, and the patient was discharged from the hospital asymptomatic with normal renal function at 25 days after the transplant. Four months later, the patient experienced bronchitis with cough and fever. Antibiotic therapy was performed with totally resolution of symptoms. At 8 months of follow-up after kidney transplantation, the patient is asymptomatic with normal renal function.

Renal allograft protection with early angiotensin-converting enzyme inhibitors administration.

Twenty renal transplant recipients (RTx) with a normal ultrasound pattern of renal artery who began angiotensin-converting enzyme inhibitor (ACEI) therapy within 14 months after surgery (ACEI(+)) were studied retrospectively to evaluate endogenous creatinine clearance/1.73 m(2) body surface area (CrCl), proteinuria (UP), UP/CrCl (FUP), mean arterial pressure (MBP), total cholesterol, LDL, HDL, and triglycerides. Before (T(0)) and every month for 2 years after initiation of ACEI. Twenty-four RTx who never received ACEI (ACEI(-)) were studied in the same fashion. No differences in the parameters were noted at T(0); all RTx had CrCl >60 mL/min, Up less than 0.5 g/d, and stable renal function for 3 months before the study. In the ACEI cohort CrCl was reduced after 2 years compared with T(0) (65.6 +/- 2.8 vs 76 +/- 3.2 mL/min, P <.004), UP and FUP were both increased (660 +/- 60 vs 130 +/- 20 mg/d, 8.9 +/- 1.3 vs 2.8 +/- 0.6 mg/mL x 10(3); P <.001 and.002, respectively). UP >0.5 g/d was present in three cases. After 2 years the ACEI(+) group showed a decrease in CrCl (68.2 +/- 3.1 vs 73 +/- 2.2 mL/min) and the increase in UP (181 +/- 21 vs 139 +/- 18 mg/d) and in FUP (3.1 +/- 0.7 vs 2.6 +/- 0.9 mg/mL x 10(3)), which were not significantly different from the values at T(0). No cases showed UP >0.5 g/d. Moreover UP (P <.04), FUP (P <.03) and the percent reduction of CrCl (11.2 +/- 2.5% vs 4.6 +/- 1.8%, P <.05) were greater among ACEI(-) than ACEI(+) patients at 2 years. ACEI(-) patients showed correlation between the percent reduction of CrCl and UP (r =.51, P <.04). The values of MBP and lipids did not reveal any significant difference between the two groups. In conclusion, this study suggests that ACEI have a renoprotective effect, when used early, and may also prevent chronic allograft nephropathy.

[Cardiovascular disease after renal transplantation]. / La malattia cardiovascolare dopo trapianto renale.

Cardiovascular disease is the leading cause of morbidity and mortality following renal transplantation. Because many renal transplant recipients die with functioning grafts, deaths resulting from cardiovascular disease have became an increasingly important cause of graft loss, particularly after the first post-transplantation year. Moreover, a contribution of some cardiovascular risk factors to renal allograft dysfunction has been demonstrated. A number of observational studies suggest that cardiovascular disease is more common in renal transplant patients than in the general population. The excessive risk for cardiovascular disease is related to a high prevalence and accumulation of atherogenic risk factors before and after transplantation. Hypertension, post-transplantation diabetes and hyperlipidemia are well-recognized risk factors for the development of cardiovascular events after renal transplantation and are strongly associated with immunosuppressive therapy. Progressive renal dysfunction may also influence the risk of cardiovascular complications after renal transplantation. The elevated risk may also be caused by non- traditional risk factors such as anaemia, adhesion molecules, hyperhomocysteinemia, microinflammatory state, abnormal coagulation and oxidative stress. To prevent post-transplantation cardiovascular disease it is crucial to define the etiological risk factors. Some risk factors can be modified, and for some of these, there is strong evidence from studies in the general population that intervention improves survival. Given the significant morbidity and mortality of cardiovascular disease in renal transplant recipients, aggressive treatment intervention for potentially modifiable factors are strongly advocated after transplantation. In addition to treatment intervention, risk management should also involve tailoring the immunosuppressive regimen to minimize both direct and indirect cardiovascular risks. In this article we attempted to review and quantify the post-transplant risk factors for cardiovascular disease as well as offer suggestions on optimizing the therapy or treatment strategies to minimize the risk of cardiovascular complications in renal transplant patients. Reduction of cardiovascular morbidity and mortality can improve not only the life expectancy and quality of life of the transplant recipients but also their graft function and survival.

Hepatitis C virus risk: a hepatitis C virus related syndrome.

BACKGROUND: The association between mixed cryoglobulinemia (MC) and hepatitis C virus (HCV) infection has been recently described in many reports. OBJECTIVE: The aim of this study was to evaluate the long-term prognosis of hepatitis C virus-positive patients affected by mixed cryoglobulinemia with or without kidney involvement. PATIENTS: At total of 119 hepatitis C virus-positive patients affected by mixed cryoglobulinemia were divided in two groups. Group A: mixed cryoglobulinemia without kidney involvement (103 cases); group B: mixed cryoglobulinemia with glomerulonephritis (GN) (16 cases). A further 37 patients affected by mesangio-proliferative glomerulonephritis (MPGN) were evaluated as controls (group C). METHODS: Anti-hepatitis C virus antibodies were determined by commercial kits and hepatitis C virus-RNA was detected by polymerase chain reaction (PCR) amplification of the 5' untranslated region (5'UTR) of the virus. The hepatitis C virus genotype was determined according to Okamoto. Liver biopsy was performed in 62 patients, bone marrow biopsy in 65 patients, and kidney biopsy in all patients with proteinuria. RESULTS: In group A, 46 patients (45%) were affected by chronic liver disease (CLD), 21 (20%) by low-grade non-Hodgkin's lymphoma (NHL) and 16 (15%) by both diseases. All patients of group B were affected by type I membrano-proliferative glomerulonephritis, 3 (19%) by chronic liver disease, 6 (37%) by low-grade non-Hodgkin's lymphoma, and 7 (44%) by both diseases. Several genotypes of hepatitis C virus were found, but Type 1b was prevalent. In group C, no patient showed chronic liver disease or non-Hodgkin's lymphoma. Younger age, higher mean blood pressure, lower C4 serum level, and poorer survival significantly distinguished group B from group A. Survival rates at 5 years were: 87.4% for group A, 89.5% for group C, and 50.0% for group B. None of the patients of group B developed kidney failure requiring dialysis, whilst infections were the leading cause of death. CONCLUSIONS: In hepatitis C virus-positive patients, the presence of mixed cryoglobulinemia associated with kidney involvement seems to indicate a new syndrome characterized by immune system impairment, lack of progression to kidney failure, and poor survival (hepatitis C virus-Risk syndrome).

Interferon therapy in HCV-positive mixed cryoglobulinaemia: viral and host factors contributing to efficacy of the therapy.

BACKGROUND: In a previous paper, we reported on the short-term efficacy of alpha-interferon in the treatment of hepatitis C virus positive mixed cryoglobulinaemia. AIMS: We investigated the long-term effects of therapy in a larger group of patients, and the viral and host factors able to influence the response to treatment. METHODS: In 27 females and 15 males (mean age 54.8 +/- 9.1 years) affected by mixed cryoglobulinaemia, bone marrow biopsy and phenotyping of marrow cells were performed before treatment and at the end of follow-up. A liver biopsy was obtained from patients showing biochemical signs of chronic liver disease. The presence of hepatitis C virus was assessed by detection of serum anti-hepatitis C virus antibodies, and hepatitis C virus-RNA. The treatment schedule was 3 million units of recombinant interferon alpha-2b three times a week for one year. Follow-up lasted for 1 year after the end of treatment. The response was classified as follows: 1) Complete response: Disappearance of the cryocrit (or reduction of more than 50%) and of all clinical manifestations of the disease. 2) Partial response: Disappearance of all clinical signs of the disease, but reduction of cryocrit of less than 50%. 3) Minor response: Reduction of cryocrit of less than 20% associated with the disappearance of one or more (but not all) signs of vasculitis. RESULTS: Anti-hepatitis C virus antibodies were present in 41 (95%) patients, and hepatitis C virus-RNA was detectable in all cases. Before therapy, marrow histology showed a massive monomorphous infiltration by plasmacytoid lymphocytes indicating the presence of low-grade non-Hodgkin lymphoma in 7 cases (16.6%). After therapy, 13 (31%) patients achieved a complete response, 23 patients (55%) a partial response, and 6 patients (14%) a minor response. Seven of the responders and all patients showing partial or minor responses relapsed a few months after withdrawal of therapy. At the end of the follow-up, only 6 patients had obtained complete remission. Bone marrow examination showed that B-lymphocytic monoclonal infiltrate had disappeared in 3 long-term responders. No difference was found between responders and non-responders/relapsers in terms of age, sex, duration of the disease, severity of symptoms, liver function tests, rheumatoid factor or complement levels, while the lack of response was associated with the presence of genotype 1b, liver cirrhosis, and high cryoglobulin level. CONCLUSIONS: Mixed cryoglobulinaemia is associated with a high prevalence of B-cell lymphomas. Alpha-Interferon is an effective agent for the treatment of this disease and seems able to determine regression of the lymphoproliferative disorder. The hepatitis C virus genotype and cryoglobulin level are the most important predictive factors of response to therapy.

Lansoprazole and ethanol metabolism: comparison with omeprazole and cimetidine.

Since some antisecretory drugs such as cimetidine and ranitidine, interfere with ethanol metabolism by inhibition of hepatic and/or gastric alcohol dehydrogenase, we investigated the effect of lansoprazole, a new protonic pump inhibitor, on gastric and hepatic alcohol dehydrogenase activity. We also compared the lansoprazole effect with that of omeprazole and cimetidine, respectively. Ethanol blood concentration after oral intake or intravenous administration of ethanol was estimated either in normal male human volunteers or in male rats before and after one week pretreatment with lansoprazole, omeprazole and cimetidine. Furthermore, the in vitro effect of these drugs was studied on both human and rat gastric and hepatic alcohol dehydrogenases. Finally, we measured the effect of the treatment on the reduced hepatic glutathione to test the effects of the drugs on first-pass metabolism of ethanol. The results reported in this paper indicate that lansoprazole, as well as omeprazole, does not affect ethanol metabolism, and that protonic pump inhibitors seem to be safer than imidazole-derived drugs in subjects unable to reduce ethanol intake during conditions requiring acid secretion inhibition.

Hepatitis C virus and non-Hodgkin's lymphomas.

Hepatitis C virus (HCV) seems to be the aetiologic agent of mixed cryoglobulinaemia, and as this 'benign' lymphoproliferative disorder can frequently develop into more aggressive haematological disorders, this study was undertaken to determine the prevalence of HCV infection in non-Hodgkin's lymphomas. 199 unselected subjects treated by three haematological centres in Northeast Italy were investigated for the presence of HCV infection. As controls, the prevalence of HCV infection was determined in a group of patients affected by other haematological malignancies (153 subjects) and in the general population of the same geographical area in the cohort study called the Dyonisos project (6917 subjects). The presence of anti-HCV antibodies was determined by a commercial kit and, in positive cases, by PCR amplification of the 5' untranslated region of the virus. The HCV genotype was also obtained by PCR amplification of the Core region with type-specific primers. The presence of serum cryoglobulins was determined in each case of NHL. HCV infection was significantly (P < 0.00000001) higher in patients with non-Hodgkin's lymphomas (28.0%) when compared with that of the general population (2.9%), and with the group of patients affected by other malignancies (3.1%). The prevalence is particularly high in low-grade (38.4%), as compared with intermediate (11.4%), or high-grade (15.2%) lymphomas. The presence of the virus is significantly (P < 0.000001) associated with the presence of detectable levels of cryoglobulins. On the basis of these findings. HCV seems to play an important role in the development of low-grade non-Hodgkin's lymphomas.