Amphotericin B removal by plasma exchange

Examination of drug removal profiles in patients undergoing therapeutic plasma exchange: A retrospective study

INTRODUCTION

Therapeutic plasma exchange (TPE) eliminates disease-contributing substances but may also affect drug concentrations. This study aimed to assess the prevalence of prescription drugs removable via TPE by reviewing patient medication histories.

METHODS

A retrospective, single-center study was conducted from January 1, 2021 to December 31, 2022. The study included 244 patients undergoing 1087 TPE sessions. Drugs prescribed to patients on TPE days were categorized as "yes" (probably removable), "maybe" (possibly removable), and "no" (unlikely removable) regarding their removability via TPE.

RESULTS

Among 3966 prescriptions, 556 (14.0%) were analyzed, with 21.8%, 36.5%, and 41.7% falling into the "yes," "maybe," and "no" categories for removability. Although only 14.0% were categorized, 83.6% of patients received at least one analyzable drug. Among them, 83.8% had at least one potentially removable drug.

CONCLUSION

Real-world data highlights the need for caution in drug treatments during TPE to ensure optimal therapeutic outcomes, particularly for specific drugs.

Effect of Therapeutic Plasma Exchange on Itraconazole Pharmacokinetics: A Case Study

ABSTRACT

The authors present the case of a 34-year-old male patient who underwent therapeutic plasma exchange (TPE) for amyopathic dermatomyositis. Immunosuppression resulted in Aspergillus lentulus pulmonary infection , requiring treatment with super bioavailable-itraconazole. Therapeutic itraconazole concentrations were attained after 2 weeks of treatment after dose adjustments. Interestingly, a substantial reduction in plasma itraconazole concentration was observed during TPE, which was attributed to an insufficient delay between the dosing of itraconazole and TPE initiation. Furthermore, there was an increase in plasma concentration post-TPE, which presumably reflects the redistribution of itraconazole from peripheral compartments back into plasma. This was confirmed by sampling of the TPE plasmapheresate, which revealed that changes in plasma concentration overestimated itraconazole clearance. These findings highlight that the pharmacokinetics of itraconazole are altered during TPE, which should be considered when timing drug administration and obtaining plasma concentrations.

Drug Dosing in Patients Undergoing Therapeutic Plasma Exchange

Therapeutic plasma exchange (TPE) is an extracorporeal process in which a large volume of whole blood is taken from the patient's vein. Plasma is then separated from the other cellular components of the blood and discarded while the remaining blood components may then be returned to the patient. Replacement fluids such as albumin or fresh-frozen plasma may or may not be used. TPE has been used clinically for the removal of pathologic targets in the plasma in a variety of conditions, such as pathogenic antibodies in autoimmune disorders. TPE is becoming more common in the neurointensive care space as autoimmunity has been shown to play an etiological role in many acute neurological disorders. It is important to note that not only does TPE removes pathologic elements from the plasma, but may also remove drugs, which may be an intended or unintended consequence. The objective of the current review is to provide an up-to-date summary of the available evidence pertaining to drug removal via TPE and provide relevant clinical suggestions where applicable. This review also aims to provide an easy-to-follow clinical tool in order to determine the possibility of a drug removal via TPE given the procedure-specific and pharmacokinetic drug properties.

Is Antimicrobial Treatment Effective During Therapeutic Plasma Exchange? Investigating the Role of Possible Interactions

Antimicrobial treatment during therapeutic plasma exchange (TPE) remains a complex issue. Recommendations based on a limited number of experimental studies should be implemented in clinical practice with caution. Effective management of infections due to plasma or albumin-related interactions, as well as impaired pharmacokinetics, in critical illness is difficult. Knowing the pharmacokinetics of the drugs concerned and the procedural aspects of plasmapheresis should be helpful in planning personalized treatment. In general, possessing a low distribution volume, a high protein-binding affinity, a low endogenous clearance rate, and long distribution and elimination half-lives make a drug more prone to elimination during TPE. A high frequency and longer duration of the procedure may also contribute to altering a drug's concentration. The safest choice would be to start and finish TPE before antimicrobial agent infusion. If this not feasible, a reasonable alternative is to avoid administering the drug just before TPE and to delay the procedure for the time of the administered drug's distributive phase. Ultimately, if plasma exchange must be performed urgently or the drug has a very narrow therapeutic index, monitoring its plasma concentration is advised.

The impact of therapeutic plasma exchange and double filtration plasmapheresis on hemostasis in renal transplant recipients

Aim. To investigate the impact of double filtration plasmapheresis (DFPP) and therapeutic plasma exchange (TPE) on hemostasis in renal transplant recipients. Materials and methods. 54 renal transplant patients with an acute humoral rejection were treated with therapeutic apheresis methods: 24 patients with DFPP and 30 patients with TPE. In all patients was performed 3-4 session. We analyzed international normalized ratio (INR), activated partial thromboplastin time (APTT), fibrinogen concentration and platelet count just before and after each session, and after the course of all procedures. After TPE plasma replacement was performed with an equivalent volume of a fresh frozen plasma. After DFPP was performed 10-20% albumin solution. Results and discussion. After each DFPP session was occurred an increased INR and aPTT. After course of all DFPP procedures fibrinogen level decreased by 46%. It was associated with increase of APTT and INR by 35% and 32% respectively. Mainly it was associated with dose of the procedures (volume of plasma perfusion), but not with the plasma separator type. One patient noted hemorrhagic complication. After each TPE session level of fibrinogen concentration, INR and aPPT remained in the normal range, but there was a moderate reduction in platelet count, more pronounced than during DFPP. Hemorrhagic complications were not. Conclusion. Double cascade plasmapheresis and therapeutic plasma exchange generate preconditions for hemorrhagic complications such as increased aPTT and INR, reduce fibrinogen concentration. However, bleeding complications are rare. At the same time, during high volume DFPP should be careful when initially level of fibrinogen is low. In this case fibrinogen concentration should be controlled after the procedure for timely replenishment of its deficit.

Impact of plasma exchange on pharmacokinetic disposition of micafungin

Change in the pharmacokinetic disposition of an antifungal agent micafungin (MCFG) by 8-hour plasma exchange (PE) with 3200 mL replacement was examined in a stem cell transplant recipient. On pharmacokinetic analysis of the time course of the serum concentrations of MCFG, it was determined that PE shortened the elimination half-life of MCFG from 16.5 hours to 6.3 hours. Total clearance (CL(tot)) was increased from 0.366 L/h to 0.932 L/h by PE. PE-dependent clearance (CL(pe)) accounted for approximately two-thirds of CL(tot), and PE was found to contribute to the removal of nearly 40% of the total body store of MCFG. It was confirmed that a significant amount of MCFG was excluded into apheresed plasma waste. In addition, adsorption of MCFG onto plasma-separating membrane was strongly suggested, because the CL(pe) exceeded the rate of plasma apheresis and MCFG concentrations in apheresed plasma were lower than those in circulating blood collected at the same time. The marked elimination of MCFG during PE can be explained by its low volume of distribution and high affinity for serum proteins. Judging from these findings as well as those of other reports, MCFG can be considered one of the drugs most susceptible to removal by PE. Our findings suggest that an increment in the regular dose of MCFG would be required at the next administration after PE.