tacrolimus and Hemolysis

We report a 17-yr-old boy who developed a microangiopathic hemolytic anemia presumed secondary to tacrolimus shortly following a living-related donor renal transplant. This was initially managed by plasmapheresis. Reinstitution of calcineurin inhibition using cyclosporine led to recurrence of hemolysis, so an alternative agent was needed. He was commenced on monthly intravenous belatacept, with no further recurrence of the hemolysis, and subsequent stable graft function. Modulation via CTLA-4 offers an alternative immunosuppressive tactic if current regimens produce graft threatening adverse effects. The method of administration and frequency of dosage of belatacept also lends itself well to the high-risk period of adolescence and transition. We propose that belatacept may therefore also have utility in difficult cases complicated by poor concordance, common in the adolescent age group.

Topics: Abatacept; Adolescent; Anemia, Hemolytic; B7-1 Antigen; B7-2 Antigen; Calcineurin; CTLA-4 Antigen; Graft Rejection; Hemolysis; Humans; Immunoconjugates; Immunosuppression Therapy; Immunosuppressive Agents; Kidney Transplantation; Living Donors; Male; Plasmapheresis; Postoperative Complications; Recurrence; Tacrolimus; Treatment Outcome

As a traditional immunosuppressive drug, tacrolimus showed the potency in treating ulcerative colitis. In this study, a novel drug delivery vehicle achieved by self-assembly was applied to tacrolimus. During the preparation, amphiphilic copolymer MPEG-PCL was chosen to form the unique core-shell structure, and tacrolimus was loaded into the hydrophobic core due to its great hydrophobicity. After several relevant tests, MPEG-PCL (2000-2000) was selected to be the most suitable and safest copolymer for drug carrier. For the tacrolimus loaded MPEG-PCL (2000-2000) micelles, the mean particle size and drug entrapment efficiency were ca. 25 +/- 5 nm and 98.47 +/- 0.43% respectively. The micelles could be stored for quite a long time even at room temperature after freeze-drying, and the freeze-drying process didn't affect the monodispersity of micelles. Transmission electron microscope (TEM) image emerged the spherical shape of micelles. Both Differential Scanning Calorimetric (DSC) and X-ray Diffractometer (XRD) assays demonstrated that tacrolimus was relatively completely incorporated into the core-shell structure. In vitro release profiles showed the apparent sustained release behavior compared with tacrolimus solution. Above all, animal treatment showed the most satisfactory therapeutic effect of tacrolimus loaded micelles, which means the micelles possess the ability to treat ulcerative colitis induced by dextran sulfate sodium (DSS) in mice. Therefore, micelles of MPEG-PCL could be a very promising novel vehicle for tacrolimus.

Topics: Animals; Body Weight; Calorimetry, Differential Scanning; Colon; Drug Delivery Systems; Hemolysis; Male; Mice; Mice, Inbred BALB C; Micelles; Microscopy, Electron, Transmission; Particle Size; Polyesters; Polyethylene Glycols; Rabbits; Tacrolimus; Temperature; X-Ray Diffraction

AIHA is a rare and serious complication of solid organ transplantation. Herein, we report four cases of warm or mixed AIHA in pediatric patients following combined liver, small bowel and pancreas transplant. The hemolysis was refractory to multiple treatment modalities including steroids, rituximab, IVIG, plasmapheresis, cytoxan, discontinuation of prophylactic penicillin, and a change in immunosuppression from tacrolimus to cyclosporine. All patients had resolution or marked improvement of hemolysis after discontinuation of maintenance of CNI and initiation of sirolimus immunosuppression. One patient developed nephrotic syndrome but responded to a change in immunosuppression to everolimus. Three of the four patients continue on immunosuppression with sirolimus or everolimus without further hemolysis, evidence of rejection or medication side effects. Based on our experience and review of similar cases in the literature, we have proposed a treatment algorithm for AIHA in the pediatric intestinal transplant patient population that recommends an early change in immunosuppressive regimen from CNIs to sirolimus therapy.

Topics: Anemia, Hemolytic, Autoimmune; Antibodies, Monoclonal, Murine-Derived; Calcineurin; Cyclophosphamide; Cyclosporine; Everolimus; Female; Hemolysis; Humans; Immunoglobulins, Intravenous; Immunosuppression Therapy; Immunosuppressive Agents; Infant; Intestines; Liver Transplantation; Male; Medical Records; Nephrotic Syndrome; Pancreas Transplantation; Penicillins; Plasmapheresis; Retrospective Studies; Rituximab; Sirolimus; Steroids; Tacrolimus; TOR Serine-Threonine Kinases; Transplantation; Treatment Outcome

Tacrolimus is an immunosuppressive drug essential for preventing organ rejection after transplantation. Since tacrolimus strongly binds to erythrocytes, therapeutic monitoring requires its quantification in whole blood lyzate, representing one of the most difficult to analyze biological fluids due to its high protein load. In this communication, we report on the successful combination of whole blood hemolysis employing ionic liquids, followed by sample preparation by means of on-line solid phase extraction (SPE) using restricted access materials (RAM), which permitted the efficient removal of hemoglobin and other large biomolecules. Among six different tested RAM columns, highest hemoglobin depletion and analyte extraction efficiency was obtained with a polymer-based, glycoprotein-coated RAM stationary phase (Biotrap 500 MS) operated at an alkaline pH of 10.7. Analyte quantification was performed by high-performance liquid chromatography-selected reaction monitoring tandem mass spectrometry (HPLC-SRM-MS/MS). The ability to quantify tacrolimus in therapeutically relevant concentrations in whole blood hemolyzates was demonstrated via external calibration with lower limits of detection and quantification of 2.00 and 7.23 ng mL(-1), respectively. Moreover, the investigation of heparin-pretreated blood samples during blood sampling led to an increase in sensitivity for the analyte, while the method appeared to be more robust with ethylenediaminetetraacetic acid as anticoagulant.

Topics: Adsorption; Calibration; Chromatography, High Pressure Liquid; Edetic Acid; Erythrocytes; Hemoglobins; Hemolysis; Heparin; Humans; Hydrogen-Ion Concentration; Immunosuppressive Agents; Ionic Liquids; Limit of Detection; Solid Phase Extraction; Spectrometry, Mass, Electrospray Ionization; Tacrolimus; Tandem Mass Spectrometry; Tissue Extracts

Tacrolimus (FK 506), a poorly soluble immunosuppressant is currently formulated in nonaqueous vehicle containing hydrogenated castor oil derivative for intravenous administration. Hydrogenated castor oil derivatives are associated with acute anaphylactic reactions. This proposes to overcome the problems of poor aqueous solubility of the drug and the toxicity associated with currently used excipients by the development of a new parenterally acceptable formulation using self-microemulsifying drug delivery system (SMEDDS). Solubility of FK 506 in various oils, surfactants, and cosurfactants was determined to identify SMEDDS components. Phase diagrams were constructed at different ratios of surfactants:cosurfactant (K(m)) to determine microemulsion existence area. Influence of oily phase content, K(m), aqueous phase composition, dilution, and incorporation of drug on mean globule size of microemulsions was studied. SMEDDSs were developed using ethyl oleate as oily phase and Solutol HS 15 as surfactant. Glycofurol was used successfully as a cosurfactant. Developed SMEDDS could solubilize 0.8% (wt/wt) FK 506 and on addition to aqueous phase could form spontaneous microemulsion with mean globule size < 30 nm. The resulting microemulsion was iso-osmotic, did not show any phase separation or drug precipitation even after 24 h, and exhibited negligible hemolytic potential to red blood cells.

Topics: Animals; Chromatography, Thin Layer; Drug Compounding; Drug Delivery Systems; Drug Design; Drug Stability; Emulsions; Female; Freezing; Hemolysis; Humans; Immunosuppressive Agents; In Vitro Techniques; Injections, Intravenous; Mice; Oils; Osmotic Pressure; Particle Size; Polyethylene Glycols; Sterilization; Surface-Active Agents; Tacrolimus

A woman on daclizumab developed thrombotic microangiopathy secondary to cyclosporine after a living-unrelated kidney transplant. Despite cyclosporine discontinuation, hemolysis persisted. The second dose of daclizumab was postponed 24 h, and after a maximum of two sessions of plasmapheresis (to avoid further modifications in daclizumab schedule) with plasma exchange, daclizumab was administered. Plasma infusions were prescribed until D-dimer and fibrinogen-degradation products normalized; thereafter, FK-506 was started without recurrence of the hemolytic picture and renal function restored. This observation suggests that in patients on daclizumab who develop thrombotic microangiopathy secondary to immunosuppressants, if discontinuation of the offending drug is unsuccessful, plasmapheresis with plasma exchange can be performed when the lowest levels of daclizumab exist, followed by daclizumab infusion. Plasma prescription must be continued thereafter until D-dimer and figrinogen-degradation products normalize. However, if hemolysis persists when daclizumab levels are high, plasma infusions are useful and plasmapheresis avoided. FK-506 administration did not result in recurrence of hemolysis during daclizumab induction.

Topics: Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Biomarkers; Blood Component Transfusion; Cyclosporine; Daclizumab; Drug Therapy, Combination; Female; Fibrin Fibrinogen Degradation Products; Hemolysis; Humans; Immunoglobulin G; Immunosuppressive Agents; Kidney Failure, Chronic; Kidney Transplantation; Living Donors; Male; Microcirculation; Middle Aged; Plasmapheresis; Polycystic Kidney Diseases; Tacrolimus; Thrombosis

Bone marrow transplantation using donors with minor ABO incompatibility may result in the rapid production of donor-derived red cell isohemagglutinins, causing hemolysis of recipient red cells.. The transplant of sibling-donor marrow with minor ABO incompatibility (group O donor marrow to group A recipient), using FK-506 as an immunosuppressant to prevent graft-versus-host disease, is reported. Following early myeloid engraftment, the recipient developed hemolysis of her entire A red cell population between Day 8 and Day 11. This brisk hemolytic anemia was due to rapid donor lymphoid engraftment that resulted in the explosive production of donor-derived anti-A.. Patients undergoing the transplantation of marrow from donors with minor ABO incompatibility in which the donor cells can produce isohemagglutinins against the recipient's red cells must be kept under vigilant observation for the possible development of severe hemolysis, particularly in the setting of profound T-cell suppression without B-cell suppression.

Topics: ABO Blood-Group System; Adult; Bone Marrow Transplantation; Hemolysis; Histocompatibility; Humans; Immunosuppressive Agents; Male; Tacrolimus

To determine the mechanism of hemolysis following organ transplantation, we studied the effect of immunosuppressants and/or superoxide (SO) on the in vitro destruction of red cells. The immunosuppressants tested included cyclosporin A (CyA), deoxyspagarine (DSG), and FK506. SO was obtained from the hypoxanthine-xanthine oxidase reaction. Of the three immunosuppressants studied, only CyA affected the size of red cells and directly produced hemolysis in an isotonic buffer without the involvement of an immune mechanism. In addition, SO and CyA showed a synergistic effect on hemolysis during prolonged incubation. Catalase and allopurinol prevented hemolysis by counteracting the activity of SO. In that SO is produced in excess during the recovery of blood flow after organ transplantation, the prolonged contact of red cells with CyA and SO may be involved in the development and reinforcement of hemolysis in vivo.

Topics: Adult; Cyclosporine; Drug Synergism; Erythrocytes; Hemolysis; Humans; Male; Superoxides; Tacrolimus

Topics: Adult; Anemia, Hemolytic; Bone Marrow Transplantation; Complement System Proteins; Erythrocytes; Female; Hemolysis; Humans; Liver Transplantation; Male; Tacrolimus