Lymphoplasmacytic hyperplasia (possibly pre-PTLD) has varied expression and appearance in intestinal transplant recipients receiving Campath immunosuppression

Risk factors associated with post-kidney transplant malignancies: an article from the Cancer-Kidney International Network

In kidney transplant recipients, cancer is one of the leading causes of death with a functioning graft beyond the first year of kidney transplantation, and malignancies account for 8-10% of all deaths in the USA (2.6 deaths/1000 patient-years) and exceed 30% of deaths in Australia (5/1000 patient-years) in kidney transplant recipients. Patient-, transplant- and medication-related factors contribute to the increased cancer risk following kidney transplantation. While it is well established that the overall immunosuppressive dose is associated with an increased risk for cancer following transplantation, the contributive effect of different immunosuppressive agents is not well established. In this review we will discuss the different risk factors for malignancies after kidney transplantation.

Aggressive posttransplant lymphoproliferative disease in a renal transplant patient treated with alemtuzumab

Post transplant lymphoproliferative disease (PTLD) is a rare but potentially fatal complication after solid organ transplantation. The risk of PTLD varies with type of organ transplant, Epstein-Barr virus serostatus of the donor and recipient, age, and intensity of immunosuppression. We report a case of a 45-year-old man who developed aggressive PTLD 7 months after receiving a cadaveric renal transplant. He received 30 mg alemtuzumab intravenously intraoperatively as induction immunosuppression followed by maintenance immunosuppression with tacrolimus and mycophenolate mofetil. The patient presented with intestinal perforation and gastrointestinal bleeding. Histopathology revealed Epstein-Barr virus-positive diffuse large B-cell lymphoma with a high mitotic index involving multiple segments of small and large intestines and leading to perforation of the ileum, jejunum, and cecum. The patient had Stage IV disease and treatment consisted of immunosuppression reduction and 375 mg/m rituximab weekly for four doses. Unfortunately, the patient had recurrent intestinal perforation followed by fatal gastrointestinal bleeding. There have been very few case reports of PTLD after alemtuzumab induction in renal transplant and the case discussed had simultaneous multiple perforations in the small intestine and colon.

Present status and future perspectives of intestinal transplantation

Intestinal transplantation (ITx) is the only definitive therapy for irreversible intestinal failure. Owing to the limited short- and long-term graft survival over the years, ITx has been a complementary treatment to home parenteral nutrition. However, the development of intestinal and multivisceral transplantation has been significant over the past 15-20 years owing to the progress in immunosuppressive therapy, refinement of surgical techniques, post-transplant care, intestinal immunology, and immunological as well as anti-infectious monitoring. The improvement of patient- and graft survival over the last few years together with data on the cost effectiveness of ITx, following 2 years after transplantation, may require a redefinition of the indication for ITx.

Characterization of CXCL13+ Neoplastic T Cells in Cutaneous Lesions of Angioimmunoblastic T-cell Lymphoma (AITL)

Skin manifestations of angioimmunoblastic T-cell lymphoma (AITL) are frequent, sometimes as first manifestations of the disease. In the absence of a specific marker for neoplastic cells, diagnosis of AITL in skin biopsies is often difficult. CD10 and CXCL13 have been recently recognized as characteristic markers of AITL, but have not been yet investigated in the skin. We analyzed 15 skin biopsies from 8 patients with AITL having skin manifestations and compared them to 14 skin biopsies from patients with various cutaneous lymphocytic infiltrates. A few CD10 lymphocytes were found in only 2 samples of the AITL group, the identification of which was hampered by the presence of a dermal CD10 cell population with dendritic features. By contrast, CXCL13 lymphoid cells were identified in most AITL cutaneous biopsies (n=12, 80%), whereas, absent in all samples from control cases. Among 12 biopsies with CXCL13 cells, cutaneous involvement by AITL was suspected in only 5 on the basis of light microscopy and classic immunophenotyping. In another case, a diagnosis of cutaneous marginal zone B-cell lymphoma had been proposed. In conclusion, this study shows that neoplastic AITL CXCL13 T cells localize in the skin and that accurate diagnosis of AITL lesions can be done in skin specimens using CXCL13 immunostaining on paraffin-embedded tissues.

Current status of transplantation of the small intestine

The evolution of small bowel transplantation has been significant over the past 20 years to the point at which it can now be considered a viable and often successful option in the treatment of many forms of short bowel syndrome. A refinement of surgical techniques, improved immunosuppression, enhanced understanding of gut immunology, and better treatment and prevention of complications have contributed to a marked improvement in graft and patient survival. Whereas this transplant population is still beset with many potential complications after isolated bowel or multivisceral transplantation and long-term graft survival (like with other solid organ transplants) remains a challenge, the future holds promise for a continuation of the current positive trend of improvement in several areas.

Small intestine transplantation today

INTRODUCTION

Intestinal transplantation has become a life-saving therapy in patients with irreversible loss of intestinal function and complications of total parenteral nutrition.

DISCUSSION

The patient and graft survival rates have improved over the last years, especially after the introduction of tacrolimus and rapamycin. However, intestinal transplantation is more challenging than other types of solid organ transplantation due to its large amount of immune competent cells and its colonization with microorganisms. Moreover, intestinal transplantation is still a low volume procedure with a small number of transplanted patients especially in Germany. A current matter of concern is the late referral of intestinal transplant candidates.

CONCLUSION

Thus, patients often present after onset of life-threatening complications or advanced cholestatic liver disease. Earlier timing of referral for candidacy might result in further improvement of this technique in the near future.

Opportunistic infections in 547 organ transplant recipients receiving alemtuzumab, a humanized monoclonal CD-52 antibody

BACKGROUND

Alemtuzumab is being increasingly used for the prevention and/or treatment of acute allograft rejection in organ transplant recipients. We assessed the risks of infection in, to our knowledge, the largest cohort and broadest range of organ transplant recipients yet reported to have received alemtuzumab.

METHODS

All patients who received alemtuzumab from September 2002 through March 2004, either as induction therapy at the time of transplantation or for the treatment of rejection, were evaluated for the development of an opportunistic infection (OI) until death or for 12 months after receipt of the last dose of alemtuzumab.

RESULTS

A total of 547 recipients were included, 65% of whom received alemtuzumab for induction therapy only. Overall, 56 recipients (10%) developed 62 OIs, including cytomegalovirus disease (n = 16), BK virus infection (n=12), posttransplantation lymphoproliferative disease (n=5), human herpesvirus 6 infection (n=1), parvovirus infection (n=1), esophageal candidiasis (n=12), cryptococcosis (n=2), invasive mold infection (n=4), Nocardia infection (n=4), mycobacterial infection (n=3), Balamuthia mandrillaris infection (n=1), and toxoplasmosis (n=1). Patients who received alemtuzumab for induction therapy were significantly less likely to develop an OI, compared with patients who received alemtuzumab for rejection therapy (4.5% vs. 21%; P<.001). Independent predictors of the development of an OI were administration of alemtuzumab for rejection therapy (odds ratio [OR], 3.5; 95% confidence interval [CI], 1.8-6.8; P<.001), allograft failure (OR, 2.1; 95% CI, 1.1-4.4; P=.04), and receipt of a lung transplant (OR, 3.7; 95% CI, 1.7-8.0; P=.001) or an intestinal transplant (OR, 8.3; 95% CI, 3.5-19.5; P<.001).

CONCLUSIONS

Patients who received alemtuzumab for the treatment of allograft rejection were significantly more likely to develop an OI, compared with patients who received alemtuzumab for induction therapy only. Such data have implications for new antimicrobial prophylactic strategies.

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Malignancy in pediatric transplant recipients

Malignancy is a well defined complication of chronic immunosuppression. Post transplant malignancies appear to be related to cumulative doses of immunosuppression, and in pediatric patients, acute infection of previously naive patients. The most commonly encountered malignancy in this age population is Post Transplant Lymphoproliferative Disorder (PTLD). PTLD is not a single entity but rather represents a continuum of disease. Treatment of PTLD should be initiated with immunosuppression reduction. Standard dose chemotherapy leads to significant morbidity. With the introduction of anti-CD20 antibody treatment with rituximab, chemotherapy has become second line therapy. The occurrence of solid malignancy appears to be associated with chronic immunosuppression. These cancers include those of skin, gynecologic organs, and the rectum, all of which appear to have the strongest association with viral mediators. Several strategies have been postulated to minimize the occurrence of malignancy. These include ganciclovir prophylaxis for the prevention of PTLD and the use of mychophenolic acid and TOR inhibitor maintenance to diminish the incidence of PTLD and solid malignancies. This leaves transplant physicians with several new and novel immunosuppressive agents with uncertain oncologic potentials that will need to be examined over the next decade.

Malignancy after transplantation

As newer immunosuppressive regimens have steadily reduced the incidence of acute rejection and have extended the life expectancy of allograft recipients, posttransplant malignancy has become an important cause of mortality. In fact, it is expected that cancer will surpass cardiovascular complications as the leading cause of death in transplant patients within the next 2 decades. An understanding of the underlying pathobiology and how to minimize cancer risks in transplant recipients are essential. The etiology of posttransplant malignancy is believed to be multifactorial and likely involves impaired immunosurveillance of neoplastic cells as well as depressed antiviral immune activity with a number of common posttransplant malignancies being viral-related. Although calcineurin inhibitors and azathioprine have been linked with posttransplant malignancies, newer agents such as mycophenolate mofetil and sirolimus have not and indeed may have antitumor properties. Long-term data are needed to determine if the use of these agents will ultimately lower the mortality due to malignancy for transplant recipients.