Fungal and mycobacterial infections after Campath (alemtuzumab) induction for renal transplantation

Preclinical pharmacology and toxicology evaluation of an anti-CD52 monoclonal antibody produced by perfusion fermentation process

Anti-cluster of differentiation 52 (CD52) monoclonal antibody (mAb) has been employed in the treatment of chronic lymphoblastic leukemia and multiple sclerosis. Previously we developed a perfusion process to produce the biosimilar mAb named “Mab-TH.” A series of quality assessments was conducted in the fields of structural identification, purity analysis, and activity measurement. After these quality researches, this report laid emphasis on preclinical pharmacology and toxicology evaluation. Mab-TH was characterized in biological, pharmacological, and toxicological properties in comparison with the original drug, alemtuzumab. Binding activity and immune-dependent toxicity as in vitro activity were evaluated. Severe immunodeficient mice transplanted with a human leukemia cell line were also used as an in vivo pharmacological model and a 4-week repeated dosing study in cynomolgus monkeys was conducted to evaluate the safety differences. Our results demonstrated that Mab-TH, the anti-CD52 antibody generated by a perfusion process, had high similarity in in vitro and in vivo activities compared with alemtuzumab in relevant preclinical models. The results supported it as a biosimilar candidate for clinical evaluation.

Posttransplantation tuberculosis management in terms of immunosuppressant cost: a case report in Myanmar

Drug interactions between anti-tuberculosis and immunosuppressive medications after renal transplantation are a common problem in Myanmar. The efficacy of both types of drugs can be reduced during the treatment period, which can lead to graft failure and flare-ups of infection. Drug adjustments, with frequent monitoring and close follow-up, are crucial in this period. Ketoconazole decreases tacrolimus metabolism by inhibiting cytochrome P450-3A5 enzymes and P-glycoprotein. It is cost effective and has been frequently used to reduce the dose and cost of tacrolimus. Here, we report the case of a 56-year-old male renal transplant recipient with anti-tuberculosis medications.

Infectious Complications of Biological and Small Molecule Targeted Immunomodulatory Therapies

The past 2 decades have seen a revolution in our approach to therapeutic immunosuppression. We have moved from relying on broadly active traditional medications, such as prednisolone or methotrexate, toward more specific agents that often target a single receptor, cytokine, or cell type, using monoclonal antibodies, fusion proteins, or targeted small molecules. This change has transformed the treatment of many conditions, including rheumatoid arthritis, cancers, asthma, and inflammatory bowel disease, but along with the benefits have come risks. Contrary to the hope that these more specific agents would have minimal and predictable infectious sequelae, infectious complications have emerged as a major stumbling block for many of these agents. Furthermore, the growing number and complexity of available biologic agents makes it difficult for clinicians to maintain current knowledge, and most review articles focus on a particular target disease or class of agent. In this article, we review the current state of knowledge about infectious complications of biologic and small molecule immunomodulatory agents, aiming to create a single resource relevant to a broad range of clinicians and researchers. For each of 19 classes of agent, we discuss the mechanism of action, the risk and types of infectious complications, and recommendations for prevention of infection.

Mycobacterium tuberculosis after solid organ transplantation: A review of more than 2000 cases

BACKGROUND

Mycobacterium tuberculosis (TB) is a common pathogen worldwide, and it may cause significant infection after solid organ transplantation (SOT). We reviewed all reported TB cases to provide an update on its epidemiology, clinical presentation, management, and outcome after SOT.

METHODS

MEDLINE, EMBASE, and OVID were reviewed from January 1, 1998, to December 31, 2016, using keywords tuberculosis and solid organ transplant or transplantation.

RESULTS

There were 187 publications reporting 2082 cases of TB among kidney (n = 1719), liver (n = 253), heart (n = 77), lung (n = 25), and kidney-pancreas (n = 8) recipients. Among cohort studies, the median incidence was 2.37% (range, 0.05%-13.27%) overall. Most TB disease was considered reactivation of latent infection, occurring beyond the first year after SOT. Early-onset cases were seen among donor-derived TB cases. Fever was the most common symptom. Radiologic findings were highly variable. Extrapulmonary and disseminated TB occurred 29.84% and 15.96%, respectively. Multidrug-resistant TB was rare. Treatment using 4 or 5 drugs was commonly associated with hepatotoxicity and graft dysfunction. All-cause mortality was 18.84%.

CONCLUSIONS

This large review highlights the complexity of TB after SOT. Reactivation TB, donor-transmitted infection, extrapulmonary involvement, and disseminated disease are common occurrences. Treatment of TB is commonly associated with hepatotoxicity and graft dysfunction.

Mycobacterium tuberculosis infection following kidney transplantation

Introduction and Aims. Post-transplant tuberculosis (TB) is a problem in successful long-term outcome of renal transplantation recipients. Our objective was to describe the pattern and risk factors of TB infection and the prognosis in our transplant recipients. Patients and Methods. This study was a retrospective review of the records of 491 renal transplant recipients in our hospital during the period from January 1986 to December 2009. The demographic data, transplant characteristics, clinical manifestations, diagnostic criteria, treatment protocol, and long-term outcome of this cohort of patients were analyzed. Results. 16 patients (3,2%) developed post-transplant TB with a mean age of 32,5 ± 12,7 (range: 13–60) years and a mean post-transplant period of 36,6months (range: 12,3 months–15,9 years). The forms of the diseases were pulmonary in 10/16 (62,6%), disseminated in 3/16 (18,7%), and extrapulmonary in 3/16 (18,7%). Graft dysfunction was observed in 7 cases (43,7%) with tissue-proof acute rejection in 3 cases and loss of the graft in 4 cases. Hepatotoxicity developed in 3 patients (18,7%) during treatment. Recurrences were observed in 4 cases after early stop of treatment. Two patients (12.5%) died. Conclusion. Extra pulmonary and disseminated tuberculosis were observed in third of our patients. More than 9months of treatment may be necessary to prevent recurrence.

Cutaneous Mycobacterium haemophilum infection in a kidney transplant recipient after acupuncture treatment

Mycobacterium haemophilum is a slow-growing nontuberculous mycobacterium that can cause disease in both immunocompetent and immunocompromised patients. The most common clinical presentations of infection are the appearance of suppurative and ulcerated skin nodules. For the diagnosis, samples collected from suspected cases must be processed under the appropriate conditions, because M. haemophilum requires lower incubation temperatures and iron supplementation in order to grow in culture. In this case report, we describe the occurrence of skin lesions in a kidney transplant recipient, caused by M. haemophilum, associated with acupuncture treatment. The diagnosis was established by direct smear and culture of material aspirated from cutaneous lesions. Species identification was achieved by characterization of the growth requirements and by partial sequencing of the hsp65 gene. The patient was successfully treated with clarithromycin and ciprofloxacin for 12 months. Considering that the number of patients receiving acupuncture treatment is widely increasing, the implications of this potential complication should be recognized, particularly in immunosuppressed patients.

The response of intestinal stem cells and epithelium after alemtuzumab administration

Intestinal stem cells may have important roles in the maintenance of epithelial integrity during tissue repair. Alemtuzumab is a humanized anti-CD52 lymphocytic antibody that is increasingly being used to induce immunosuppression; intestinal barrier function is impaired during treatment with alemtuzumab. We investigated the response of intestinal stem cells to epithelial damage resulting from alemtuzumab treatment. Intestinal epithelial cell loss and abnormal Paneth cell morphology were found following a single dose of alemtuzumab. The animals receiving alemtuzumab exhibited increased apoptosis in the villi 3 days after alemtuzumab treatment and in the crypt on day 9, but apoptosis was scarce on day 35. We assessed expression of Musashi-1- and Lgr5-positive stem cells following alemtuzumab treatment. Increased numbers of cells staining positive for both Musashi-1 and Lgr5 were found in the stem cell zone after alemtuzumab treatment for 3 and 9 days. These data indicated that the epithelial cells were injured following alemtuzumab treatment, with the associated expansion of intestinal stem cells. After alemtuzumab treatment for 35 days, the numbers of intestinal epithelial cells and intestinal stem cells returned to normal. This study suggests that alemtuzumab treatment induced the increase in stem cells, resulting in the availability of more enterocytes for repair.

Influence of alemtuzumab on the intestinal Paneth cells and microflora in macaques

Alemtuzumab has been recently introduced for induction therapy in organ transplantation. However, the pathogenesis and molecular mechanism of the impact of such induction therapy on bacterial infections remain to be clarified. We found the alterations of Paneth cells including abnormal Paneth cell granules and expression of lysozyme and defensin 5 in response to lymphocyte depletion by alemtuzumab. Lymphocyte depletion resulted in decreased expression of TNF-alpha, IFN-gamma, IL-10 and TGF-beta in the intestine. The diversity of gut bacteria varied significantly between different times of alemtuzumab treatment. Abnormal expression of granule peptides might result in impairment of host gut microflora. The alterations in bacterial microflora had almost reversed 56days after alemtuzumab treatment, which was consistent with our results that Paneth cells were recovered to secrete antimicrobial peptides to govern gut microflora. These findings indicated the associations between changes of Paneth cell function and gut microflora and supported the important role of Paneth cells to barrier impairment with the use of alemtuzumab in organ transplantation.

Mycobacterium tuberculosis infection in transplant recipients: early diagnosis and treatment of resistant tuberculosis

PURPOSE OF REVIEW

To provide a better understanding and summarize recent advances in the diagnosis and treatment of Mycobacterium tuberculosis (MTB) infection in solid organ transplant (SOT) candidates and recipients.

RECENT FINDINGS

Despite advances in SOT medicine, MTB causes substantial morbidity and mortality in SOT recipients, with reported prevalence rates of 0.4-6%. The primary source of posttransplant MTB is reactivation of pretransplant latent MTB infection. The short-term mortality rate in SOT recipients with drug-susceptible active MTB is 30%. In immunocompromised persons with extensively drug-resistant MTB, the mortality rate approaches 100%. Clinical presentation is often atypical with more than half of SOT recipients presenting with extrapulmonary or disseminated disease. Pretransplant latent MTB infection screening and treatment is the cornerstone for preventing reactivation and dissemination of active MTB posttransplant. Treatment of active MTB in SOT recipients is problematic, given significant drug toxicity and interaction with immunosuppressive agents.

SUMMARY

A high degree of suspicion for latent and active MTB infection in SOT candidates and recipients is warranted to establish a timely diagnosis and initiate life-saving appropriate therapy.

A randomized trial of alemtuzumab versus antithymocyte globulin induction in renal and pancreas transplantation

BACKGROUND.: Alemtuzumab and rabbit antithymocyte globulin (rATG) are commonly used for induction of immunsuppression for kidney and pancreas transplantation, but the two agents have not been compared directly. METHODS.: We conducted a prospective randomized single-center trial comparing alemtuzumab and rATG induction in adult kidney and pancreas transplantation in patients treated with similar maintenance immunosuppression. RESULTS.: Between February 1, 2005, and September 1, 2007, 222 patients randomly received either alemtuzumab (n=113) or rATG (n=109) induction; 180 (81%) underwent kidney alone, 38 (17%) simultaneous pancreas-kidney, and 4 (2%) pancreas after kidney transplants. Of 180 kidney-alone transplants, 152 (84%) were from deceased donors, including 61 (34%) from expanded criteria donors. Retransplantation, human leukocyte antigen match, antibody titer, expanded criteria donors, race, cytomegalovirus status, delayed graft function, and immunologic risks were similar between the two induction groups. With a median follow-up of 2 years (minimum 1 year), overall patient, kidney, and pancreas graft survival rates were 96%, 89%, and 90%, respectively. Survival, initial length of stay, and maintenance immunosuppression (including early steroid elimination) were similar between alemtuzumab and rATG groups, but biopsy-proven acute rejection (BPAR) episodes occurred in 16 (14%) alemtuzumab patients compared with 28 (26%) rATG patients (P=0.02). Late BPAR (>12 months after transplant) occurred in 1 (8%) alemtuzumab patient and 3 (11%) rATG patients (P=NS). Infections and malignancy were similar between the two induction arms. CONCLUSION.: Alemtuzumab and rATG induction therapies were equally safe, but alemtuzumab was associated with less BPAR.

Cryptococcus neoformans fatal sepsis in a chronic lymphocytic leukemia patient treated with alemtuzumab: case report and review of the literature

Cryptococcosis is a disseminated fungal disease typically associated with immunosuppression and characterized by high mortality rates. Cryptococcus neoformans has been reported to be isolated from blood cultures in around 20% of patients with cryptococcosis, and cryptococcemia has been correlated with poor prognosis. We report a case of fatal C. neoformans fungemia in a neutropenic patient with a history of chronic lymphocytic leukemia treated with alemtuzumab. The patient presented with loss of consciousness and died after 5 days of antifungal therapy with liposomal amphotericin B. The international literature regarding opportunistic infections after immunosuppressive therapy with alemtuzumab with particular attention on fungal infections has also been reviewed.

Islet transplantation with alemtuzumab induction and calcineurin-free maintenance immunosuppression results in improved short- and long-term outcomes

BACKGROUND

Only a minority of islet transplant recipients maintain insulin independence at 5 years under the Edmonton protocol of immunosuppression. New immunosuppressive strategies are required to improve long-term outcomes.

MATERIALS AND METHODS

Three subjects with unstable type 1 diabetes mellitus underwent islet transplantation with alemtuzumab induction and sirolimus-tacrolimus maintenance for 3 months and then sirolimus-mycophenolic acid maintenance thereafter. Follow-up was more than 2 years. Comparison was with 16 historical subjects transplanted under the Miami version of the Edmonton protocol.

RESULTS

Insulin independence was achieved in 2 of 3 alemtuzumab and 14 of 16 historical subjects. Those who did not achieve insulin independence only received a single islet infusion. Insulin-independence rates remained unchanged in the alemtuzumab group, but decreased from 14 of 16 (88%) to 6 of 16 (38%) in the historical group over 2 years. Insulin requirements increased in the historical group while remaining stable in the alemtuzumab group. Comparison of functional measures at 3 months suggested better engraftment with alemtuzumab (P=NS). Further comparison of alemtuzumab versus historical groups, up to 24 months, demonstrated significantly better: Mixed meal stimulation index (24 months, 1.0+/-0.08 [n=3] vs. 0.5+/-0.06 pmol/mL [n=6], P<0.01), mixed meal peak C-peptide (24 months, 5.0+/-0.5 [n=3] vs. 3.1+/-0.3 nmol/mL [n=6], P<0.05), HbA1c (24 months, 5.4+/-0.15 [n=3] vs. 6.3+/-0.12 pmol/mL [n=10], P<0.01). Administration of alemtuzumab was well tolerated. There was no increased incidence of infections in alemtuzumab subjects despite profound, prolonged lymphocyte depletion.

CONCLUSIONS

Islet transplantation with alemtuzumab induction was well tolerated and resulted in improved short- and long-term outcomes. Further investigation is underway for validation.