Microglia-derived HIV Nef+ exosome impairment of the blood-brain barrier is treatable by nanomedicine-based delivery of Nef peptides.

The negative factor (Nef) of human immunodeficiency virus (HIV) is an accessory protein that is thought to be integral to HIV-associated immune- and neuroimmune pathogenesis. Here, we show that nef-transfected microglia-released Nef+ exosome (exNef) disrupts the apical blood-brain barrier (BBB) and that only nef-transfected microglia release Nef in exosomes. nef-gfp-transduced neurons and astrocytes release exosomes but did not release exNef in the extracellular space. Apical administration of exNef derived from nef-transfected 293T cells reduced transendothelial electrical resistance (TEER) and increased permeability of the BBB. Microglia-derived exNef applied to either the apical/basal BBB significantly reduced expression of the tight junction protein, ZO-1, suggesting a mechanism of exNef-mediated neuropathogenesis. Microglia exposed to exNef release elevated levels of Toll-like receptor-induced cytokines and chemokines IL-12, IL-8, IL-6, RANTES, and IL-17A. Magnetic nanoparticle delivery of Nef peptides containing the Nef myrisolation site across an in vitro BBB ultimately reduced nef-transfected microglia release of Nef exosomes and prevented the loss of BBB integrity and permeability as measured by TEER and dextran-FITC transport studies, respectively. Overall, we show that exNef is released from nef-gfp-transfected microglia; exNef disrupts integrity and permeability, and tight junctions of the BBB, and induces microglial cytokine/chemokine secretion. These exNef-mediated effects were significantly restricted by Nef peptides. Taken together, this study provides preliminary evidence of the role of exNef in HIV neuroimmune pathogenesis and the feasibility of a nanomedicine-based therapeutics targeting exNef to treat HIV-associated neuropathogenesis.

Targeting strategies for Human immunodeficiency virus: a combinatorial approach.

The battle between human and the Human immunodeficiency virus (HIV) is on, with both of them rapidly improving their attacking and defense strategies. Many therapeutic agents for HIV infection have been designed and developed, However there are various aspects, like novel targets against HIV, which are yet to be unfolded with a goal of designing and developing novel drug molecules against HIV. This article reviews the current status and innovative new options for antiretroviral therapy for HIV and also discusses the various mechanisms of action for each class of drugs, and the problems yet to be solved with respect to HIV as a target for improvised treatment against AIDS.

Posttransplantation calcineurin inhibitor-induced hemolytic uremic syndrome: single-center experience.

INTRODUCTION: Calcineurin inhibitor (CNI) induced HUS, although rare, can be a serious complication of renal transplantation. Classical syndrome of microangiopathic hemolytic anemia, thrombocytopenia, and acute renal injury may not be fully manifested. METHODS: We retrospectively analyzed our data in 950 kidney recipients under follow-up in our center (1994-2008). We reviewed the kidney biopsies performed for these patients to exclude conflicting diagnoses like antibody mediated rejection. RESULTS: HUS was diagnosed in 12 patients (1.26%). None of them had HUS as the original kidney disease. Cyclosporine was the primary immunosuppression in 9 and tacrolimus in 3 patients. The median day of onset was 7 days. Manifestations were anemia (100%), thrombocytopenia (75%), elevated reticulocyte count (62.5%), fragmented red blood cells (8.3%), elevated lactate dehydrogenase (LDH) enzyme (83.3%), increased fibrin degradation product (FDP) (83.3%), reduced haptoglobin level (42.9%) and hyperbilirubinemia (25%). CNI elimination was the first step in the management. Transfusion of fresh frozen plasma (FFP) was used in 10 patients and plasma exchange with FFP in the other two. All grafts recovered function. Cyclosporine or tacrolimus were reintroduction in two patients after complete clinical and laboratory recovery. Both patients developed recurrence of HUS. While the former did not the latter did recover on further treatment of HUS. CONCLUSION: Anemia, thrombocytopenia, elevated LDH and FDP are the most frequent manifestations of HUS. Early CNI elimination and fresh plasma transfusion can revert CNI induced HUS and save the graft. Reintroduction of CNI may be deleterious to the graft and should be avoided.

Erythema nodosum in renal transplant recipients: multiple cases and review of literature.

We report 4 renal transplant recipients with erythema nodosum. Erythema nodosum is a cutaneous inflammatory reaction located on the anterior aspects of the lower extremities. It may be associated with a wide variety of diseases, including infections (as in Cases 1 and 2), sarcoidosis, rheumatologic diseases, inflammatory bowel diseases (as in Case 3), medications (as in Case 4), autoimmune disorders, pregnancy, and malignancies. Histopathologically, erythema nodosum is the stereotypical example of a mostly septal panniculitis with no vasculitis, and the inflammatory infiltrate in the septa varies with age of the lesion. In early lesions edema, hemorrhage, and neutrophils are responsible for the septal thickening, whereas fibrosis, peri-septal granulation tissue, lymphocytes, and multinucleated giant cells are the main findings in late stage. Etiological management - by anti-tuberculous therapy in Cases 1 and 2, by salazopyrin in Case 3, and by discontinuation of ciprofloxacin in Case 4 - was associated with regression. Erythema nodosum can develop in renal transplant patients who did not receive induction therapy, non-rejecters, and those with steroid-free protocols. Management of erythema nodosum should be directed to the underlying associated condition, which could be tuberculosis, inflammatory bowel disease, or drug related.

Early sirolimus therapy in renal transplant recipients at high risk: is it justified?

BACKGROUND: We studied early sirolimus (SRL) therapy in renal transplant recipients at high risk after administration of antithymocyte globulin or interleukin-2 receptor blockade induction. PATIENTS AND METHODS: In 45 patients, SRL therapy was started within 1 month after transplantation. The primary indications for conversion of treatment from calcineurin inhibitors (CNIs)-mycophenolate mofetil (MMF)-steroid to SRL-MMF-steroid were biopsy-proved rejection (after treatment), CNI toxicity, CNI elimination, and acute tubular necrosis. Pediatric, geriatric, and other patients with medical comorbidities were not excluded. RESULTS: Post-SRL rejection episodes were reported in 22.2% of recipients including 15.6% who were resistant to steroid therapy. Mean (SD) follow-up after SRL therapy was 59.9 (8.1) months. Proteinuria greater than 2 g/d (P = .001), leukopenia (P < .001), hyperlipidemia (P < .001), and transaminases values (P = .02) increased significantly after SRL therapy. Graft survival was 88.8%, and patient survival was 93.3%. There was significant improvement in serum creatinine concentration and estimated creatinine clearance by the end of the study (P < .001). A high incidence of adverse effects and infections was noted post-SRL therapy, and the drug was discontinued in 31% of patients because of multiple adverse effects. At multivariate analysis, age, hypertension, nutritional status, bone marrow suppression, hyperlipidemia, and graft dysfunction were identified as risk factors for worse graft and patient outcome. CONCLUSION: Early treatment with combined SRL-MMF-steroid may be effective as a CNI-free immunosuppression regimen in patients at high risk; however, there is a high rate of adverse effects during long-term follow-up.

Long-term follow-up of 100 high-risk renal transplant recipients converted from calcineurin inhibitors to sirolimus: a single center experience.

While conversion of stable renal transplant recipients (RTR) from calcineurin inhibitors (CNI) to sirolimus (SRL) is safe and effective, it is still under investigation for recent, high-risk cases. We studied the long-term effects of conversion of high-risk subjects maintained on a CNI, mycophenolate mofetil, plus steroid regimen to SRL, mycophenolate mofetil, plus steroid on graft and patient outcomes. We retrospectively reviewed the first 100 RTR converted to SRL treatment over approximately 5 years. The main indications for conversion were biopsy-proven acute rejection (BPAR), CNI toxicity, CNI elimination, and acute-tubular necrosis (ATN). Exclusion criteria were limited to bone marrow suppression. The overall mean +/- SD age was 38.5 +/- 15.6 years, including pediatric and geriatric age groups. Mean +/- SD body mass index (BMI) was 28.99 +/- 8.0 and 40% had a BMI > 30. There were 40% RTR from deceased donors and 60% showed 4 to 6 HLA mismatches. Preconversion total BPAR and steroid-resistant rejection incidences were 35% and 14%, respectively. Mean +/- SD time to start of SRL was 11.9 +/- 22.8 months posttransplantation. Proteinuria > 2 g/d, leukopenia, and hyperlipidemia increased significantly after conversion (P = .001, P = .0003, and P = .0001, respectively). Patient and graft survivals were 95% and 90%, respectively. There was significant improvement in graft function postconversion (P < .0001). There was a high incidence of side effects and cases of SRL discontinuation. Multivariate analysis demonstrated the influence of bone marrow suppression, obesity, hyperlipidemia, nutritional status, proteinuria, and graft function on graft and patient outcomes. We concluded that conversion from CNI to SRL was effective among high-risk RTR, but with a high incidence of adverse events during long-term follow-up.

Hyperinfection strongyloidiasis: an anticipated outbreak in kidney transplant recipients in Kuwait.

BACKGROUND: Hyperinfection strongyloidiasis is a potentially fatal syndrome associated with conditions of depressed host cellular immunity. A high degree of suspicion is required to detect cases early and thereby avoid a fatal outcome. PATIENTS AND METHODS: Three consecutive cadaveric kidney transplant recipients died within 2 months from hyperinfections with strongyloides. All members of the transplant team were involved in a campaign to localize the source of infection, identify and treat affected patients, and provide adequate prophylaxis to other transplant recipients. We reviewed cadaveric donor files and screened 61 hospital personnel, 27 hospital inpatients, and the 87 hospital outpatients transplanted in a year's time before that event for a possible source. The screening test included analysis of fresh stool samples on 3 consecutive days for strongyloides larvae. The anti-helminthic drug albendazol was administered to all patients during screening. They were followed for possible development of the disease during the infectivity period. RESULTS: The first 2 recipients received their kidneys from 1 cadaveric donor, while the third received it from a different donor. Both donors came from areas endemic for strongyloidiasis. The 3 recipients were on tacrolimus-based immunosuppression. The twin recipient of the second kidney was on cyclosporine and did not manifest a disease. All stool samples taken for screening were negative for the infective larvae. None of the other recipients developed the disease. CONCLUSIONS: Cadaveric donors were the possible source for this outbreak. Cyclosporine probably has a protective effect against strongyloides. In our setting, screening of cadaveric donors for strongyloides is mandatory before accepting them for donation, and oral prophylaxis is required for all recipients.

Cerebral aspergillosis diagnosed by detection of Aspergillus flavus-specific DNA, galactomannan and (1-->3)-beta-D-glucan in clinical specimens.

A case of cerebral aspergillosis was diagnosed by the detection of Aspergillus flavus-specific DNA in brain biopsy and serum specimens. The diagnosis was also supported by detection of elevated levels of galactomannan and (1-->3)-beta-d-glucan in serum specimens. Despite the presence of dichotomously branched septate hyphae in brain biopsy, the culture remained negative. The inability to isolate the organism in culture suggested that combined therapy of AmBisome and caspofungin was fungicidal for the fungus in the brain abscess.

The area under the concentration-time curve versus trough and peak blood level monitoring in renal transplant recipients on cyclosporine.

OBJECTIVE: The area under the concentration-time curve of cyclosporine microemulsion is the best measure of the absorption and beneficial effects in renal transplant recipients. We sought to determine the best method of monitoring cyclosporine levels in these patients. METHODS: Prospective evaluation of peak cyclosporine blood levels and area under the curve monitoring were performed for 1 year in 65 renal transplant recipients (study group). Cyclosporine trough levels and peak cyclosporine blood levels were correlated with the calculated area under the curve. Cyclosporine trough levels were monitored in equal numbers of matched controls. RESULTS: There were no significant differences in the incidence of acute rejection, cyclosporine nephrotoxicity, proteinuria, serum creatinine levels, or graft and patient outcomes between the groups (P = .1). Peak cyclosporine blood levels guided by calculating the area under the curve were found to be 27% to 32% lower than previously reported. The correlation coefficient was <70% for cyclosporine trough levels (P < .02) and >90% for peak cyclosporine blood levels (P < .001) when related to the calculated area under the curve. The calculated area under the curve was approximately 6000 ng/mL/h following transplantation, gradually decreasing to approximately 3000 ng/mL/h at 1 year. Both appeared to the acceptable therapeutic values. CONCLUSION: Calculating the area under the curve using trough and peak blood levels versus using isolated readings for either of these levels alone is the most effective method of monitoring cyclosporine in recipients undergoing renal transplant.

Single daily dose administration of cyclosporine in renal transplant recipients: a preliminary report.

INTRODUCTION: Cyclosporine microemulsion has been the mainstay immunosuppressive agent in renal transplantation for years. Since single daily dosing of cyclosporine is rarely used, the objective of this investigation was to evaluate the efficacy of a single daily dose versus twice daily dosing of cyclosporine in renal transplant recipients. METHODS: Retrospective evaluation of single-dose cyclosporine use was conducted for 15 renal transplant recipients for 12 months (study group). Equal numbers of matched renal transplant recipients were selected for age, sex, human leukocyte antigen mismatch, donor type, and immunosuppressive regimen (control group). Cyclosporine trough level and peak cyclosporine blood levels, 12-hour cyclosporine profile, and the area under the concentration-time curve were measured. RESULTS: There was a significant difference in cyclosporine peak blood level and calculated area under the curve after shifting to single-dose cyclosporine (P = .001). In the study group, the mean area under the curve was significantly below the average therapeutic range before (3154 ng/mL/ho) versus 5532 ng/mL/h after shifting to the single-dose regimen (which was therapeutic). This value was 5749 ng/mL/h in the control group. Total daily cyclosporine dose was lower in the study group when compared with the control group at 6 and 12 months (P = .01). There were significantly fewer adverse effects in patients in the study group than in patients in the control group. CONCLUSION: We conclude that although cyclosporine dose should be individualized in renal transplant recipients, a single dose of cyclosporine has the added advantage of decreasing dosages and cyclosporine-related adverse effects while maintaining optimal graft function.

Early acute rejection episodes in renal transplantation in relation to immunosuppression protocols: an audit of 100 cases.

INTRODUCTION: Early acute rejection episodes (ARE) have deleterious effects on graft outcomes. The incidence of ARE in the first 3 months has been reported to be <20%. In a recent audit of ARE among 100 renal transplants, we observed the rates to be high (30%). We retrospectively collected details of donor type, induction therapy, immunosuppression medications, drug levels, HLA mismatches, acute tubular necrosis (ATN), and delayed graft function (DGF) to correlate with ARE and response to therapy. RESULTS: Thirty rejection episodes occurred after a mean period of 14.3 days after transplantation. Ninety-one patients had induction treatment with either antithymocyte globulin (ATG) or interleukin 2 receptor antibodies (IL2 Rab). The drugs included cyclosporine, mycophenolate, sirolimus, azathioprine, and prednisolone in these patients. There was no significant difference in ARE among the different drug protocols (30.7%-35.2%). Subjects with 4 or more HLA mismatches displayed more ARE (40.3%) compared with those with 3 or less (23%). Subjects with ATN or DGF immediately posttransplantation had a higher incidence of ARE (39.2%) than those without them (26.3%). Deceased donor recipients had a higher episode of ARE (45.1%) compared with live related donor recipients (25%). On stratifying the known risk factors for ARE, subjects with no risk factors had the least (22.2%) ARE compared with those with one (32.5%) or two (47.6%) risk factors. Subjects who failed to achieve adequate cyclosporine (C2) levels showed significantly higher rates of ARE (86.9%) than those with adequate or higher levels (8.6%). CONCLUSION: Higher HLA mismatches, DGF, deceased donor, and failure to achieve adequate cyclosporine levels were observed to be major risk factors for the development of ARE.

Safety of caspofungin for treating invasive nasal sinus aspergillosis in a kidney transplant recipient.

INTRODUCTION: Invasive fungal sinusitis is a rare but often fatal infection in immunocompromised patients. Aggressive antifungal treatment is mandatory, but is not without risk. Caspofungin, an antifungal agent that is a member of the echinocandin family, an inhibitor of glucan synthesis in the fungal wall, is active against Aspergillus and Candidae infections. Although it works on the fungal wall, it does not affect mammalian cells; hence, its toxicity is minimal. CASE SUMMARY: This report describes a case of invasive Aspergillus sinusitis in a kidney transplant recipient with diabetes mellitus. The infection involved the apex of the right orbit causing optic nerve compression. The patient was treated with transnasal endoscopic decompression of the optic nerve and intravenous AmBisome (liposomal amphotericin B) for 2 weeks without clinical improvement. The combination of caspofungin and AmBisome administered for another 2 weeks yielded partial improvement. The AmBisome had to be discontinued due to deterioration of renal and hepatic function, but the patient completed a further 7-week course of caspofungin alone. Retro-orbital biopsy confirmed a complete response to treatment; the patient's renal and hepatic function returned to normal. CONCLUSION: This case indicates that caspofungin is effective to treat invasive Aspergillus sinusitis in kidney transplant recipients. This agent is well tolerated and safe with respect to renal and hepatic function.

Cytomegalovirus prophylaxis with ganciclovir in kidney transplant recipients receiving induction antilymphocyte antibodies.

BACKGROUND: Cytomegalovirus (CMV) is one of the serious viral infections after organ transplantation, especially in patients receiving anti-lymphocyte antibodies. Prevention of the infection using antiviral chemotherapy (ganciclovir) has gained interest in the transplant community due to the availability of quantitative methods for viral detection and monitoring. METHODS: Forty-six CMV seropositive kidney transplant recipients were assigned to receive induction immunosuppression with anti-thymocyte globulin (ATG, Fresenius). Prophylactic intravenous ganciclovir was administered for 2 weeks at a dose of 5 mg/kg/d (adjusted to kidney function) starting from the day of surgery. Patients were monitored regularly for CMV infection or disease over 1 year posttransplant. The time to CMV manifestation, the number of antigenemia assay-positive cells, the clinical severity of infection, the incidence of acute rejection, the graft function, and the duration of hospital stay were evaluated. This group was compared to a historical matched control cohort (n = 37) transplanted earlier who did not receive prophylactic ganciclovir. RESULT: The incidence of CMV disease was significantly less among the prophylaxis than the control group (6/46 patients [13%] vs 16/37 patients [43.2%], P = <.004). The time to develop CMV manifestations was much longer in the prophylaxis group than in the control group (median 92 vs 32 days, P

Role of non-invasive ventilation in difficult-to-wean children with acute neuromuscular disease.

Weaning from mechanical ventilation in children could be time-consuming and on many occasions, leads to reintubation with its associate complications. We report two children with acute neuromuscular disease, in whom bi-level positive airway pressure (BiPAP) as a mode of non-invasive ventilation was successfully used to wean the child from ventilators and prevented the need for tracheostomy. Despite the limited number of studies published in the literature suggesting BiPAP as a mode of weaning from mechanical ventilation, the technique when applied correctly seems to be safe and effective in weaning and avoiding tracheostomy.