The therapeutic prescription for the organ transplant recipient: the linkage of immunosuppression and antimicrobial strategies

Efficacy and safety of carrimycin in ten patients with severe pneumonia following solid organ transplantation

BACKGROUND

The number of patients undergoing solid organ transplantation has increased annually. However, infections in solid organ transplant recipients can have a severe effect on patient survival owing to the continued use of immunosuppressants. Carrimycin is a novel macrolide antibiotic produced by genetically engineered streptomyces spiramyceticus harboring a 4''-O-isovaleryltransferase gene (ist) from streptomyces thermotoleran. Carrimycin has good antibacterial and antiviral effects. However, no relevant studies have been conducted on the efficacy and safety of carrimycin in patients with severe pneumonia (SP) after solid organ transplantation.

AIM

To explore the efficacy and safety of carrimycin in patients with SP after solid organ transplantation to provide a medication reference for clinical treatment.

METHODS

In March 2022, ten patients with SP following solid-organ transplantation were treated at our hospital between January 2021 and March 2022. When the condition was critical and difficult to control with other drugs, carrimycin was administered. These ten patients' clinical features and treatment protocols were retrospectively analyzed, and the efficacy and safety of carrimycin for treating SP following solid organ transplantation were evaluated.

RESULTS

All ten patients were included in the analysis. Regarding etiological agent detection, there were three cases of fungal pneumonia, two cases of bacterial pneumonia, two cases of Pneumocystis pneumonia, and three cases of mixed infections. After treatment with carrimycin, the disease in seven patients significantly improved, the course of the disease was significantly shortened, fever was quickly controlled, chest computed tomography was significantly improved, and oxygenation was significantly improved. Finally, the patients were discharged after curing. One patient died of acute respiratory distress syndrome, and two patients discontinued treatment.

CONCLUSION

Carrimycin is a safe and effective treatment modality for SP following solid organ transplantation. Carrimycin may have antibacterial and antiviral effects in patients with SP following solid organ transplantation.

Clinical Analysis of Pulmonary Nocardiosis in Patients With Autoimmune Disease

Nocardiosis is an opportunistic infection that most commonly involves the lung; however, only a few case reports of autoimmune disease complicated by pulmonary nocardiosis exist in the literature. We conducted a retrospective analysis of 24 cases of both autoimmune disease and pulmonary nocardiosis at the Peking Union Medical College Hospital between 1990 and 2012. Fifty-two cases were hospitalized with nocardiosis, 24 of whom had at least 1 autoimmune disease before the diagnosis of pulmonary nocardiosis. The cohort patients consisted of 5 men and 19 women, with a mean age of 44.2 years. All were negative for human immunodeficiency virus. All but 1 patient had received immunosuppressants, including corticosteroids, cyclophosphamide, azathioprine, methotrexate, or hydroxychloroquine. Fever (87.5%), cough (83.3%), and sputum (79.2%) were the most common clinical manifestations. Ten cases were accompanied by subcutaneous nodules and/or cutaneous abscesses, and 4 had brain abscess. Half of them were lymphocytopenic. Thirteen of the 16 cases who underwent lymphocyte subtype analysis had decreased CD4+ T-cell counts. Nineteen cases had decreased serum albumin levels. Nocardia was isolated from sputum (13/24), bronchoalveolar lavage fluid (4/6), lung tissue (5/6), pleural effusions (3/5), skin or cutaneous pus (7/10), and brain tissue (1/1). The most common imaging findings were air-space opacities (83.3%), followed by nodules (62.5%), cavitations (45.8%), and masses (37.5%). Five were administered co-trimoxazole only, and the others were treated with 2 or more antibiotics. All 5 cases with skin abscesses and 2 of the 4 cases with brain abscesses were treated by surgical incision and drainage. None underwent thoracic surgery. Corticosteroid dosages were decreased in all cases, and cytotoxic agents were discontinued in some cases. Twenty-two cases recovered, and 2 died. Pulmonary nocardiosis associated with an underlying autoimmune disease showed a female predominance and presentation at younger age. Immunosuppressant therapy, lymphocytopenia, particularly low CD4+ T-lymphocyte counts, and low serum albumin levels may be disease susceptibility factors. Air-space opacities and nodules were the most common chest imaging features, and disseminated nocardiosis with lung and skin involvement was more common among them. Early diagnosis and anti-nocardial antibiotics with modulation of the basic immunosuppressive therapy were important for them.

Development of a rapid serological assay for the diagnosis of strongyloidiasis using a novel diffraction-based biosensor technology

BACKGROUND

Strongyloidiasis is a persistent human parasitic infection caused by the intestinal nematode, Strongyloides stercoralis. The parasite has a world-wide distribution, particularly in tropical and subtropical regions with poor sanitary conditions. Since individuals with strongyloidiasis are typically asymptomatic, the infection can persist for decades without detection. Problems arise when individuals with unrecognized S. stercoralis infection are immunosuppressed, which can lead to hyper-infection syndrome and disseminated disease with an associated high mortality if untreated. Therefore a rapid, sensitive and easy to use method of diagnosing Strongyloides infection may improve the clinical management of this disease.

METHODOLOGY/PRINCIPAL FINDINGS

An immunological assay for diagnosing strongyloidiasis was developed on a novel diffraction-based optical bionsensor technology. The test employs a 31-kDa recombinant antigen called NIE derived from Strongyloides stercoralis L3-stage larvae. Assay performance was tested using retrospectively collected sera from patients with parasitologically confirmed strongyloidiasis and control sera from healthy individuals or those with other parasitoses including schistosomiasis, trichinosis, echinococcosis or amebiasis who were seronegative using the NIE ELISA assay. If we consider the control group as the true negative group, the assay readily differentiated S. stercoralis-infected patients from controls detecting 96.3% of the positive cases, and with no cross reactivity observed in the control group These results were in excellent agreement (κ = 0.98) with results obtained by an NIE-based enzyme-linked immunosorbent assay (ELISA). A further 44 sera from patients with suspected S. stercoralis infection were analyzed and showed 91% agreement with the NIE ELISA.

CONCLUSIONS/SIGNIFICANCE

In summary, this test provides high sensitivity detection of serum IgG against the NIE Strongyloides antigen. The assay is easy to perform and provides results in less than 30 minutes, making this platform amenable to rapid near-patient screening with minimal technical expertise.

Nocardiosis in transplant recipients

Nocardiosis is a rare opportunistic infection caused by Nocardia spp., an aerobic actinomycete, that mainly affects patients with cell-mediated immunity defects, such as transplant recipients. Despite recent progress regarding Nocardia identification and changes in taxonomic assignment, many challenges remain for the diagnosis or management of nocardiosis. This opportunistic infection affects 0.04 to 3.5 % of patients with solid organ or hematopoietic stem cell transplantation, depending on the organ transplanted, cytomegalovirus (CMV) infection, corticosteroids dose and calcineurin inhibitors level. Nocardiosis diagnosis relies on appropriate clinical, radiological and microbiological workup that includes the sampling of an accessible involved site and molecular microbiology tools. In parallel, extensive clinical and radiological evaluations are mandatory, including brain imaging, even in the absence of neurological signs. In transplanted patients, differential diagnosis is challenging, with co-infections reported in 20 to 64 % of cases. As the antibiotic susceptibility pattern varies among species, the antimicrobial regimen before species identification should rely on the association of antibiotics active on all species of Nocardia. Bactericidal antibiotics are required in cases of severe or disseminated disease. Furthermore, in transplant recipients, combination therapy is difficult to manage because of cumulative toxicity and interactions with immunosuppressive agents. Because of a high recurrence rate, antibiotic therapy should be prescribed for 6 to 12 months.

The occurrence and prevention of foodborne disease in vulnerable people

In developed countries, such as the United Kingdom and the United States, between 15% and 20% of the population show greater susceptibility than the general population to foodborne disease. This proportion includes people with primary immunodeficiency, patients treated with radiation or with immunosuppressive drugs for cancer and diseases of the immune system, those with acquired immune-deficiency syndrome and diabetics, people suffering from liver or kidney disease or with excessive iron in the blood, pregnant women, infants, and the elderly. Malnutrition and use of antacids, particularly proton-pump inhibitors, also increase susceptibility. We review the occurrence of infection by foodborne pathogens in these groups of people and measures to prevent infection. The nature and use of low microbial diets to reduce the risk of foodborne disease in immunocompromised patients are very variable. Diets for vulnerable people in care should exclude higher-risk foods, and vulnerable people in the community should receive clear advice about food safety, in particular avoidance of higher-risk foods and substitution of safer, nutritious foods.

Prevention and treatment of infectious complications after solid organ transplantation in children

Effective prevention, diagnosis, and treatment of infectious diseases after transplantation are key factors contributing to the success of organ transplantation. Most transplant patients experience different kinds of infections during the first year after transplantation. Children are at particular risk of developing some types of infections by virtue of lack of immunity although they may be at risk for other types due the effect of immunosuppressive regimens necessary to prevent rejection. Direct consequences of infections result in syndromes such as mononucleosis, pneumonia, gastroenteritis, hepatitis, among other entities. Indirect consequences are mediated through cytokines, chemokines, and growth factors elaborated by the transplant recipient in response to microbial replication and invasion, which contribute to the net state of immunosuppression among other effects. This review summarizes the major infections that occur after pediatric organ transplantation, highlighting the current treatment and prevention strategies, based on the available data and/or consensus.

Qualitative studies of the food safety knowledge and perceptions of transplant patients

Organ and stem cell transplant patients are at risk for foodborne illness due to disease and medically induced immunosuppression. The food safety knowledge and informational needs of these groups have not been documented in the literature. The objectives of this study were to assess transplant patients' food safety knowledge and perceptions, to probe the likelihood of practicing safe food handling behavior, and to test an educational strategy for future food safety interventions aimed at transplant patients. Subjects were organ or stem cell transplant patients, or their family care providers. Research was conducted in inpatient or outpatient facilities at a large, Midwestern United States comprehensive cancer and transplant center. Differences in survey data between the organ and stem cell transplant groups were determined by Student's t tests. Ethnographic methods were used to analyze qualitative focus groups and interview data for themes. Organ transplant patients had less motivation to follow food safety recommendations than did stem cell transplant patients, and they were more likely to consume risky foods. Stem cell transplant patients overall had a better understanding of their susceptibility to foodborne illness and had better prepared themselves with the knowledge and behavior changes needed to protect their health. Educational materials aimed at communicating food safety information for transplant patients were evaluated by patients and judged acceptable. This study found that organ transplant and stem cell transplant patients are distinct patient populations, with differing perceptions regarding the seriousness of foodborne illness and willingness to adopt preventative food handling practices. Population differences should be accounted for in food safety educational strategies.

Pretransplant lymphocyte count predicts the incidence of infection during the first two years after liver transplantation

Patients with end-stage liver disease (ESLD) show a low absolute number of peripheral blood lymphocyte subpopulations (PBLSs). We investigated if the baseline PBLS could categorize orthotopic liver transplantation (OLT) recipients into groups at high or low risk for infection after transplantation. PBLSs were prospectively studied in 63 consecutive patients (42 males; mean age +/- standard deviation: 53.5 +/- 10.3 years) with ESLD prior to OLT. Thirty-five patients (55.6%) developed a total of 79 infectious episodes during the first 2 years post-OLT. The median total lymphocyte count and PBLS levels [CD3+ T cells, CD4+ T cells, memory (CD45RO+) CD4+ T cells, T cell receptor alphabeta+ and gammadelta+ subsets, and CD19+ B cells] at baseline were significantly lower in patients with an infection compared with those without one (P < 0.05). There was a significant correlation between the risk of development of a post-OLT infection and a baseline total lymphocyte count < 1.00 x 10(3)/microL (P = 0.001), a baseline CD3+ T cell count < 0.75 x 10(3)/microL (P = 0.009), and a baseline CD4+ T cell count < 0.5 x 10(3)/microL (P = 0.008). In the multivariate analysis, this association between the baseline total lymphocyte level and infection remained significant (odds ratio: 10.1; 95% confidence interval: 1.9-39.5). In conclusion, the pre-OLT total lymphocyte count identifies a subset of patients at high risk for infection. PBLS monitoring prior to OLT may offer an opportunity for surveillance, tapering of immunosuppression, and preemptive therapy.

Selective effects of cyclosporine a on Th2-skewed dendritic cells matured with viral-like stimulus by means of toll-like receptors

Successful prevention of allograft rejection and graft-versus-host disease with immunosuppression depends on controlled balance of Th1 and Th2 immune responses to establish tolerance and fight infection. Here, we have analyzed the effects of cyclosporine A (CsA) on the differentiation and functions of dendritic cells (DC2) that induce Th2 T cells. DC2 were differentiated from monocytes in the presence of CsA and were matured with viral or bacterial agonists (poly[I:C] or lipopolysaccharide). DC2 differentiation was not affected by CsA. In contrast, cytokine responses were altered with inhibition of interleukin-10 production in poly(I:C)-matured DC2. Surprisingly, interleukin-10 secretion by immature DC2 was increased after CsA treatment. Internalization was impaired in treated DC2, and CsA decreased the T-cell proliferative capacity of DC2 matured with poly(I:C), but not with lipopolysaccharide. In conclusion, CsA altered T-cell activating functions of DC2 with, notably, a regulatory phenotype for immature DC2 and opposite effects on poly(I:C)-matured cells.

Delivery of rapamycin to dendritic cells using degradable microparticles

Degradable microparticles have the potential to protect and release drugs over extended periods and, if sized appropriately, can be passively targeted to phagocytic cells in vivo. Dendritic cells (DC) are a class of phagocytic cells known to play important roles in transplant rejection. Previously, we have demonstrated that DC treated with an immunosuppressive drug, rapamycin, have the ability to suppress transplant rejection. Herein, we describe a strategy to deliver an intracellular depot of rapamycin to DC. To achieve this, rapamycin was encapsulated into ~3.4 microm sized poly(lactic-co-glycolic)acid (PLGA) microparticles (rapaMPs), and release behavior was examined under intra-phagosomal (pH=5) and extracellular (pH=7.4) conditions. It was observed that 4 days following phagocytosis of rapaMP, DC have significantly reduced ability to activate T cells, in comparison to DC treated with soluble rapamycin. Hence, we conclude that DC-specific intracellular delivery of rapamycin results in better efficacy of the drug, with respect to its ability to modulate DC function, when compared to treating DC with extracellular rapamycin.

Factors Influencing the Magnitude and Clinical Significance of Drug Interactions Between Azole Antifungals and Select Immunosuppressants

The magnitude of drug interactions between azole antifungals and immunosuppressants is drug and patient specific and depends on the potency of the azole inhibitor involved, the resulting plasma concentrations of each drug, the drug formulation, and interpatient variability. Many factors contribute to variability in the magnitude and clinical significance of drug interactions between an immunosuppressant such as cyclosporine, tacrolimus, or sirolimus and an antifungal agent such as ketoconazole, fluconazole, itraconazole, voriconazole, or posaconazole. By bringing similarities and differences among these agents and their potential interactions to clinicians' attention, they can appreciate and apply these findings in a individualized patient approach rather than follow only the one-size-fits-all dosing recommendations suggested in many tertiary references. Differences in metabolism and in the inhibitory potency of cytochrome P450 3A4 and P-glycoprotein influence the onset, magnitude, and resolution of drug interactions and their potential effect on clinical outcomes. Important issues are the route of administration and the decision to preemptively adjust dosages versus intensive monitoring with subsequent dosage adjustments. We provide recommendations for the concomitant use of these agents, including suggestions regarding contraindicated combinations, those best avoided, and those requiring close monitoring of drug dosages and plasma concentrations.

Infectious complications in renal transplant recipients

Post-kidney transplant infection is the most common life-threatening complication of long-term immunosuppressive therapy. Optimal immunosuppression, in which a balance is maintained between prevention of rejection and avoidance of infection, is the most challenging aspect of posttransplantation care. The study of infectious complications in immunologically compromised recipients is changing rapidly, particularly in the fields of prophylactic and preemptive strategies, molecular diagnostic methods, and antimicrobial agents. In addition, emerging pathogens such as BK polyomavirus and West Nile flavivirus infections and the introduction of newer immunosuppressive agents that constantly change the risk profiles for opportunistic infections has added layers of complexity to this burgeoning field. Although remarkable progress has been made in these disciplines, comprehensive understanding of the clinical manifestations of infections remains limited, and the standardization of prophylaxis, diagnosis, and treatment of most infections is yet inadequately defined. The long-term goal for optimal care of transplant recipients, with respect to infection, is the prevention and/or early recognition and treatment of infections while avoiding drug-related toxicities.

Infectious complications associated with alemtuzumab use for lymphoproliferative disorders

BACKGROUND

Alemtuzumab is an emerging therapy for refractory lymphoproliferative disorders. The associated long-term risks of infection remain poorly defined.

METHODS

From July 2001 through December 2003, all patients who received alemtuzumab for the treatment of lymphoproliferative disorders at 1 institution underwent a retrospective evaluation to document infectious complications until death or end of follow-up in October 2004. Alemtuzumab recipients who underwent allogeneic hematopoietic stem cell transplantation were compared with a concurrent cohort who also underwent allogeneic hematopoietic stem cell transplantation but did not receive alemtuzumab.

RESULTS

Twenty-seven patients were identified (21 with chronic lymphocytic leukemia and 6 with plasma cell disorders). The overall mortality was 37%, with 7 of 10 deaths being related to infection. Significant opportunistic infections occurred in 9 patients (43%) with chronic lymphocytic leukemia, including cytomegalovirus, progressive multifocal leukoencephalopathy, adenovirus, toxoplasmosis, and acanthamaebiasis. Thirty nonopportunistic infections in 22 patients (82%) were also identified. The 3 deaths related to nonopportunistic infections all involved Enterococcus species bacteremia. When compared with a concurrent chronic lymphocytic leukemia cohort that underwent allogeneic hematopoietic stem cell transplantation, alemtuzumab recipients had an incidence of cytomegalovirus reactivation of 66.7% (6 of 9 patients), compared with 37% in the non-alemtuzumab group (10 of 27 patients; P = .15), and an incidence of post-transplant opportunistic infections (excluding herpesviruses) of 44.4% (compared with 29.6% in the non-alemtuzumab group; P = .41).

CONCLUSIONS

Despite the use of herpesvirus and Pneumocystis pneumonia prophylaxis, serious infectious complications occur in patients receiving alemtuzumab for lymphoproliferative disorders. Infectious complications are more varied and diverse in patients receiving alemtuzumab than has been reported in trials to date.

The prevention of infection post-transplant: the role of prophylaxis, preemptive and empiric therapy

The close linkage of infection with the nature and intensity of the transplant immunosuppressive program has led to the concept of the therapeutic prescription. This has two components: an immunosuppressive one to prevent or treat rejection and graft-versus-host disease and an antimicrobial one to make it safe. This review provides a conceptual framework to approach the risk and risk periods for infection in solid organ and hematopoietic stem cell transplant recipients as well as an approach to antimicrobial use in this population.

Infectious Complications in Renal Transplant Recipients

Renal transplantation has become a well-established therapeutic option for end-stage renal disease, but infectious diseases remain a significant cause of morbidity and mortality. Although a wide variety of pathogens may cause infection, viral ones must be regarded as the single most important class of infections. Progress has been made both in the prevention and the early recognition treatment of infections that are closely linked to rejection. Immunosuppressive therapy is central to the pathogenesis of both. Because of the particular characteristics of transplant recipients, it is desirable to establish a close collaboration between nephrologists, surgeons, and infectious disease specialists for the management of these patients. In this article, we describe the different kinds of infectious disease that may affect patients with kidney transplant and the fundamental principles of clinical management, particularly our experience in Polyoma virus (BK) infection.

Cytomegalovirus prophylaxis with valganciclovir in kidney, pancreas-kidney, and pancreas transplantation

Cytomegalovirus, seen in more than 50% of solid organ transplant recipients, is responsible for numerous direct and indirect consequences, including infection with opportunistic pathogens and allograft rejection. Prophylaxis with intravenous ganciclovir has been the gold standard for prevention; however, intravenous treatment is expensive and carries risks of its own. Oral ganciclovir, to be effective, must be given in large, divided doses. Valganciclovir, the valine ester of ganciclovir, at 900 mg/day, provides oral bioavailability equivalent to that of intravenous ganciclovir and superior to that of oral ganciclovir. This retrospective study assessed the efficacy of 3 months prophylaxis with valganciclovir in kidney, simultaneous pancreas-kidney, and pancreas transplantation. Of 161 patients, all of whom received potent immunosuppressive regimens and were followed for a mean of 440 days, only one developed cytomegalovirus infection, at 120 days post-transplantation. Two patients died, and two others lost their grafts. There were seven incidents of acute rejection. Only seven patients discontinued treatment early, five because of leukopenia. These results suggest that prophylaxis with 900 mg/day of valganciclovir for at least 3 months safely and effectively prevents cytomegalovirus infection in kidney, simultaneous pancreas-kidney and pancreas transplant recipients on highly potent immunosuppression.

Impact of Cytomegalovirus Match on Survival after Cardiac and Lung Transplantation

Acute cytomegalovirus (CMV) disease and indirect effects caused by the virus alter the outcome after solid organ transplantation. Long-term results after 54 lung and 139 cardiac transplants at a single center have been retrospectively analyzed with regard to CMV status. Standard CMV prophylaxis consisted of ganciclovir for 100 days. Lung recipients were pretransplant CMV negative in 32 per cent as compared to heart recipients with 23 per cent. Patient survival after mismatch transplants (donor positive, recipient negative) was significantly reduced as compared to the other match groups (42% vs 76% at five years, P = 0.01). In heart recipients, CMV positive patients receiving a CMV negative graft showed best survival, whereas in the group of lung recipients negative/negative matched transplants produced best results. In both groups, CMV negative grafts had a better outcome than CMV positive grafts, and a survival difference between heart and lung recipients was only observed in recipients of a CMV positive grafts. Despite ganciclovir prophylaxis, CMV match remains an important factor for survival follwing heart and, even more profoundly, lung transplantation. Because survival was least favorable in the mismatched group, prophylactic regimens warrant improvement. For CMV negative lung recipients, CMV matching might be considered.

Salvage therapy with voriconazole for invasive fungal infections in patients failing or intolerant to standard antifungal therapy

BACKGROUND

Invasive fungal infections (IFI), particularly those caused by Aspergillus and other angioinvasive molds, are associated with an excessive mortality despite therapy.

METHODS

Voriconazole was prescribed on a compassionate basis to patients with IFI who were intolerant to or who had progressed despite standard therapy. Outcome was determined by protocol-based criteria as established by the consensus definitions (complete response [CR], partial response [PR], stable disease, failure, and intolerance).

RESULTS

Forty-five patients were enrolled in a compassionate release program (29 [64%] because of failure of response to standard therapy), between 1998 and 2002. Of the 45 patients enrolled, 35 (78%) had invasive Aspergillus, 3 (7%) had Fusarium, and 2 (4%) had Scedosporium infections. Underlying illnesses were as follows: 13 (29%) solid-organ transplant (SOT), 11 (24%) BMT, and 7 (13%) hematologic malignancy. Site of infection was as follows: 26 (58%) pulmonary, 9 (20%) disseminated, 5 (11%) central nervous system (CNS), and 3 (7%) sinus. Overall response rates were as follows: 9 (20%) CR, 17 (38%) PR, 15 (33%) failure, and 4 (9%) intolerant. Seven of the eight (88%) patients with sinus or CNS disease demonstrated stabilization of the IFI. The median duration of voriconazole therapy was 79 days with 9 (20%) patients receiving over 1 year of therapy. Nine thousand one hundred twenty-eight days of therapy were given with only four serious adverse events in two cases considered possibly or probably drug related.

CONCLUSIONS

In this population of severely immunocompromised patients with life-threatening IFI who have failed or were intolerant to standard antifungal therapy, voriconazole demonstrated substantial efficacy and an acceptable level of toxicity.

Diagnostic yield of bronchoalveolar lavage following renal transplantation

Organ transplant recipients are at high risk of infectious pulmonary complications. In this retrospective study, the diagnostic yield of bronchoalveolar lavage (BAL) was evaluated in renal transplant recipients. The results were analysed in special regard to the clinical presentation of pulmonary infections and the possible impact of new immunosuppressive agents. Over a 5-year period 91 BAL were performed in 71 renal transplant recipients. Microorganisms were isolated from 69% of BAL (63/91): bacteria 32%; cytomegalovirus (CMV) 27%; Pneumocystis carinii (PC) 22%; other viruses 9% (HSV; EBV, RSV, adenovirus, HHV8); Aspergillus fumigatus 1%. Total cell counts and neutrophil counts in BAL were significantly elevated in bacterial infection, whereas BAL positive for PC showed eosinophilia (P<0.05). There was no association between clinical symptoms and the radiological pattern of infiltrates and the type of infection. Immunosuppression containing tacrolimus or mycophenolate mofetil was associated with a significantly higher percentage of PC and CMV infections compared to cyclosporin-based immunosuppression (65% vs. 30%, P<0.005). A considerable number of PC and CMV infections occurred beyond 6 months after transplantation. In conclusion, BAL has a high diagnostic yield in renal transplant recipients. Infection with CMV and PC should also be considered beyond 6 months after transplantation, and prophylaxis for opportunistic infections should be given if the immunosuppression is intensified.