Possible increase of the neurotoxicity of vincristine by the concurrent use of posaconazole in a young adult with leukemia

Acute fluconazole toxicity: a case presenting with protean manifestations including systemic and neurologic symptoms

Neurologic adverse effects of triazole antifungal compounds used for the treatment of systemic and deep mycoses are relatively rare. The most common presentation is the involvement of peripheral nervous system, usually presenting with subjective symptoms such as paresthesia, dysesthesia, or numbness. Among these compounds, fluconazole has relatively more frequent neurological adverse reactions.A 54-year-old man was admitted with numbness and weakness in his both feet, which gradually worsened and resulted in difficulty in ambulation over time. He had no morbidity other than hypertension. He developed polyneuropathy (PNP), lower gastrointestinal system bleeding, acute renal insufficiency, thrombotic thrombocytopenic purpura, and confusional state. Severely disabling axonal and demyelinating sensorimotor PNP which led to immobilization of the patient for a few weeks but was recovered. When a more detailed past medical history was taken, he admitted to ingestion of 200 mg/day fluconazole for 1 month for onychomycosis without any prescription. This unusual combination of these rare adverse reactions of fluconazole may be explained by activation of an immune mechanism triggered by the drugs and genetic factors, or some other unknown individual factors.This case is reported due to the presence of rare systemic and neurologic adverse events of fluconazole, leading to this unusual clinical picture. We would like to emphasize fluconazole-related systemic and neurologic adverse reactions with life-threatening potential should be kept in mind.

Vincristine toxicity with co-administration of fluconazole during induction therapy for pediatric acute lymphoblastic leukemia

BACKGROUND

Antifungal prophylaxis is recommended for patients with acute lymphoblastic leukemia (ALL) during high-risk periods such as induction; however, increased vincristine toxicities have been reported with the co-administration of triazole antifungals. We sought to determine whether vincristine-associated toxicities are higher among children with ALL concurrently given fluconazole prophylaxis compared to no prophylaxis.

PROCEDURE

Using a retrospective cohort design, we reviewed records of pediatric patients treated for newly diagnosed ALL from 2003 to 2013. Patients were classified by fluconazole exposure during induction. The development of vincristine-associated toxicity and vincristine dose adjustment were the primary outcomes evaluated. The adjusted risk difference (RD) for vincristine-related toxicity associated with triazole exposure was determined.

RESULTS

We identified 197 patients meeting inclusion criteria for evaluation, 160 (81%) of whom received fluconazole prophylaxis. Among patients receiving fluconazole, 36/160 (22%) developed vincristine toxicity compared to 7/37 (19%) among those not receiving prophylaxis (RD: 3%, 95% confidence interval [CI] -11 to 18%). Adjusting for patient age and race, no statistically significant increased risk for vincristine-associated toxicity with fluconazole exposure was observed (RD 5%, 95% CI -8 to 17%). An increased risk for vincristine-associated toxicity was independently associated with age 10 years or older (RD 19%, 95% CI 4-34%).

CONCLUSION

Co-administration of fluconazole during induction therapy for pediatric ALL does not significantly increase the risk for vincristine-associated toxicities; however, patients 10 years or older are at an increased risk for toxicity independent of fluconazole exposure. Prophylaxis with fluconazole during induction therapy for pediatric ALL, if warranted, appears to be a safe clinical practice.

Evaluation of the implementation rate of primary antifungal prophylaxis and the prognosis of invasive fungal disease in acute leukemia patients in China

BACKGROUND

Invasive fungal disease (IFD) is a major complication of acute leukemia, thus primary antifungal prophylaxis (PAP) is recommended by guidelines. Nevertheless, guidelines might not be commonly followed in developing countries due to economic factors. The primary objectives were to evaluate the implementation rate of PAP in acute leukemia patients in China and to compare the prognosis of IFD with and without PAP. The secondary objectives were to investigate the safety of PAP, clinical characteristics of IFDs and risk factors of breakthrough.

METHODS

This was a retrospective observational single-center study, including non-M3 acute myeloid leukemia (AML) and acute lymphocytic leukemia (ALL) patients receiving uniform induction or salvage chemotherapy between 2012 and 2016.

RESULTS

There were 29.4% of patients without PAP among a total of 248 cases. The incidence of breakthrough proven/probable/possible IFDs was 24.7%, 6.5%, 5.5%, 5.4% and 5.3% in control (no prophylaxis), fluconazole, itraconazole, voriconazole and posaconazole group respectively (P = 0.007), while the percentage of patients requiring empirical or pre-emptive therapy was 54.8%, 45.7%, 23.3%, 18.9%, 10.5% respectively (P < 0.001). PAP could also significantly improve IFD-free survival (P < 0.001) and reduce 90-day overall mortality in patients on AML salvage regimen (P = 0.021). There were no statistical differences in PAP-related adverse events. Past history of IFD (OR 9.5, P = 0.006) was confirmed to be independent risk factors.

CONCLUSIONS

There are a considerable number of acute leukemia patients without PAP in China, who have higher IFD incidence, increased empiric/pre-emptive antifungal drug use and worse IFD-free survival.

Hyperlipidemia Alters the Pharmacokinetics of Posaconazole and Vincristine Upon Co-Administration in Rats

Objectives

Co-administration of posaconazole (PSZ) and vincristine (VCR) in the treatment of patients with acute lymphoblastic leukemia increases the neurotoxicity of VCR. Our aim is to study the effect of increased lipoprotein levels on the pharmacokinetics of PSZ and VCR upon co-administration in rats.

Methods

Rats were assigned to three groups, normolipidemic (NL), intermediate hyperlipidemic (IHL), and extreme hyperlipidemic (HL) groups. All rats were administered PSZ orally followed by VCR intravenously 4 h later. For the pharmacokinetic study, serial plasma samples were collected over 96 h and for tissue distribution study; plasma, lung, and liver tissues were collected over 48 h post oral dosing.

Results

Posaconazole showed higher plasma concentrations than VCR at all time points. Co-administration of VCR with PSZ reduced PSZ weight normalized oral clearance, increased PSZ area under the plasma concentration–time curve (AUC) from time zero to infinity, showed higher PSZ liver concentrations, and increased VCR volume of distribution of the central compartment. Upon increasing the lipoprotein levels, PSZ showed higher plasma availability and delayed tissue distribution, whereas VCR had shown a significant decrease in PSZ AUC_0-24h, AUC_0-tlast, and AUC_o-inf (NL = IHL > HL) and a significant increase in the volume of distribution (NL = IHL < HL). Vincristine has shown higher tissue uptake and concentrations.

Conclusion

Monitoring cholesterol and triglyceride levels in patients with acute lymphoblastic leukemia is advisable to decrease VCR neurological side effect incidences and delay the activity of both PSZ and VCR.

Consensus guidelines for optimising antifungal drug delivery and monitoring to avoid toxicity and improve outcomes in patients with haematological malignancy, 2014

Antifungal agents may be associated with significant toxicity or drug interactions leading to sub-therapeutic antifungal drug concentrations and poorer clinical outcomes for patients with haematological malignancy. These risks may be minimised by clinical assessment, laboratory monitoring, avoidance of particular drug combinations and dose modification. Specific measures, such as the optimal timing of oral drug administration in relation to meals, use of pre-hydration and electrolyte supplementation may also be required. Therapeutic drug monitoring (TDM) of antifungal agents is warranted, especially where non-compliance, non-linear pharmacokinetics, inadequate absorption, a narrow therapeutic window, suspected drug interaction or unexpected toxicity are encountered. Recommended indications for voriconazole and posaconazole TDM in the clinical management of haematology patients are provided. With emerging knowledge regarding the impact of pharmacogenomics upon metabolism of azole agents (particularly voriconazole), potential applications of pharmacogenomic evaluation to clinical practice are proposed.

Posaconazole-vincristine coadministration triggers seizure in a young female adult: a case report

Coadministration of azoles and vincristine has been shown to increase vincristine neurotoxic effects due to the inhibition of cytochrome P450 (CYP) isoform 3A4, for which vincristine is a substrate. Despite the absence of any casual relationship between seizure and coadministration of azoles, few case reports of vincristine-induced seizure have been documented after coadministration of fluconazole or posaconazole in children. In this paper we are reporting the first young female adult who experienced generalized seizure after coadministration of posaconazole and vincristine. The 19-year-old female was diagnosed with acute lymphoblastic leukemia. She started induction phase of Berlin Frankfurt Muenster protocol along with posaconazole 200 mg three times daily as prophylactic antifungal therapy. Five days after the third vincristine dose, she developed generalized seizure accompanied by high blood pressure and SIADH. Her neurological exam/CT scan did not show any abnormality. In conclusion, this study reports a novel finding in the sense that all previous case reports pertaining to posaconazole-vincristine-induced seizure in literature involved children. Physicians should be made aware of this rare possible outcome to closely monitor their patients and take appropriate measures to prevent such possible adverse effect.

Chemical denervation of the renal artery by vincristine in swine. A new catheter based technique

BACKGROUND

Renal sympathetic denervation is a promising technique for the treatment of resistant hypertension. We evaluated a novel method for chemical sympathetic denervation of the renal artery by local delivery of vincristine, an antineoplastic drug with potential for peripheral neurotoxicity, using a dedicated catheter in an animal model.

METHODS

Local delivery of vincristine by a specially designed catheter, was performed unilaterally in the renal arteries of 14 juvenile Landrace swine. The procedure was then repeated in the contralateral renal artery using a placebo mixture. Animals were euthanized at 28 days and histological specimens of renal arteries and perirenal arterial stroma containing renal nerves were extracted and sectioned. The number of uninjured nerves in each histological section was then quantified, following identification by immunohistochemical staining.

RESULTS

In all animals delivery of vincristine and placebo mixtures was successful and uncomplicated. Both vincristine- and placebo-treated renal arteries were angiographically patent at the end of the procedure. The mean number of intact nerves in all sections was significantly lower in the group of vincristine (p<0.05).

CONCLUSIONS

Catheter-based delivery of vincristine in the renal artery of an experimental model is feasible and results in significant reduction in the number of renal nerves. Our findings warrant further confirmation in animal and human studies.

Adverse interactions between antifungal azoles and vincristine: review and analysis of cases

Triazole and imidazole antifungal agents inhibit metabolism of vincristine, leading to excess vinca alkaloid exposure and severe neurotoxicity. Recent reports of debilitating interactions between vincristine and itraconazole, as well as posaconazole, voriconazole and ketoconazole underscore the need to improve medical awareness of this adverse combination. We, therefore, undertook a comprehensive analysis of reports of adverse drug interactions (ADIs) with the combination of vincristine and azole antifungal agents, established a new classification, and provided a detailed summary of these toxicities. In patients who had sufficient data for analysis, 47 individuals were identified who had an ADI with the combination of vincristine and antifungal azoles. Median age was 8 years (1.3-68 years) with 33(70%) having a diagnosis of acute lymphoblastic leukaemia. Median time to ADI with vincristine was 9.5 days with itraconazole, 13.5 days posaconazole and 30 days voriconazole. The median number of vincristine doses preceding the ADI was 2 doses with itraconazole, 3 doses posaconazole and 2 doses voriconazole. The most common severe ADIs included gastrointestinal toxicity, peripheral neuropathy, hyponatremia/SIADH, autonomic neuropathy and seizures. Recovery from these ADIs occurred in 80.6% of patients. We recommend using alternative antifungal agents if possible in patients receiving vincristine to avoid this serious and potentially life-threatening drug interaction.

Risk of azole-enhanced vincristine neurotoxicity in pediatric patients with hematological malignancies: old problem - new dilemma

One of the most well-known drug interactions in pediatric oncology concerns the co-administration of itraconazole, an antifungal triazole, and vincristine, an antileukemic agent, which seems to enhance the risk of neurotoxicity of the latter, mediated through the cytochrome CYP450 enzyme system. The aim of this article is to review the metabolism of these two drugs, to analyze the published cases with severe triazole-enhanced vincristine neurotoxicity, to discuss the pathophysiological mechanisms of this adverse effect, and to contribute in understanding the differences in triazole-vincristine interaction severity.

Clinical practice guideline for the use of antimicrobial agents in neutropenic patients with cancer: 2010 update by the infectious diseases society of america

This document updates and expands the initial Infectious Diseases Society of America (IDSA) Fever and Neutropenia Guideline that was published in 1997 and first updated in 2002. It is intended as a guide for the use of antimicrobial agents in managing patients with cancer who experience chemotherapy-induced fever and neutropenia. Recent advances in antimicrobial drug development and technology, clinical trial results, and extensive clinical experience have informed the approaches and recommendations herein. Because the previous iteration of this guideline in 2002, we have a developed a clearer definition of which populations of patients with cancer may benefit most from antibiotic, antifungal, and antiviral prophylaxis. Furthermore, categorizing neutropenic patients as being at high risk or low risk for infection according to presenting signs and symptoms, underlying cancer, type of therapy, and medical comorbidities has become essential to the treatment algorithm. Risk stratification is a recommended starting point for managing patients with fever and neutropenia. In addition, earlier detection of invasive fungal infections has led to debate regarding optimal use of empirical or preemptive antifungal therapy, although algorithms are still evolving. What has not changed is the indication for immediate empirical antibiotic therapy. It remains true that all patients who present with fever and neutropenia should be treated swiftly and broadly with antibiotics to treat both gram-positive and gram-negative pathogens. Finally, we note that all Panel members are from institutions in the United States or Canada; thus, these guidelines were developed in the context of North American practices. Some recommendations may not be as applicable outside of North America, in areas where differences in available antibiotics, in the predominant pathogens, and/or in health care-associated economic conditions exist. Regardless of venue, clinical vigilance and immediate treatment are the universal keys to managing neutropenic patients with fever and/or infection.

Adverse effects of treatment in childhood acute lymphoblastic leukemia: general overview and implications for long-term cardiac health

Survival of childhood acute lymphoblastic leukemia (ALL) is one of the greatest medical success stories of the last four decades. Unfortunately, childhood ALL survivors experience medical late effects that increase their risk of morbidity and premature death, often due to heart and vascular disease. Research has helped elucidate the mechanisms and trajectory of direct damage to the heart from treatment exposure, particularly to anthracyclines, and has also contributed knowledge on the influences of related chronic conditions, such as obesity and insulin resistance on heart health in these survivors. This article summarizes the key issues associated with early morbidity and mortality from cardiac-related disease in childhood ALL survivors and suggests directions for interventions to improve long-term outcomes.

Executive Summary: Clinical Practice Guideline for the Use of Antimicrobial Agents in Neutropenic Patients with Cancer: 2010 Update by the Infectious Diseases Society of America

This document updates and expands the initial Infectious Diseases Society of America (IDSA) Fever and Neutropenia Guideline that was published in 1997 and first updated in 2002. It is intended as a guide for the use of antimicrobial agents in managing patients with cancer who experience chemotherapy-induced fever and neutropenia.

Recent advances in antimicrobial drug development and technology, clinical trial results, and extensive clinical experience have informed the approaches and recommendations herein. Because the previous iteration of this guideline in 2002, we have a developed a clearer definition of which populations of patients with cancer may benefit most from antibiotic, antifungal, and antiviral prophylaxis. Furthermore, categorizing neutropenic patients as being at high risk or low risk for infection according to presenting signs and symptoms, underlying cancer, type of therapy, and medical comorbidities has become essential to the treatment algorithm. Risk stratification is a recommended starting point for managing patients with fever and neutropenia. In addition, earlier detection of invasive fungal infections has led to debate regarding optimal use of empirical or preemptive antifungal therapy, although algorithms are still evolving.

What has not changed is the indication for immediate empirical antibiotic therapy. It remains true that all patients who present with fever and neutropenia should be treated swiftly and broadly with antibiotics to treat both gram-positive and gram-negative pathogens.

Finally, we note that all Panel members are from institutions in the United States or Canada; thus, these guidelines were developed in the context of North American practices. Some recommendations may not be as applicable outside of North America, in areas where differences in available antibiotics, in the predominant pathogens, and/or in health care–associated economic conditions exist. Regardless of venue, clinical vigilance and immediate treatment are the universal keys to managing neutropenic patients with fever and/or infection.

Vincristine: Can its therapeutic index be enhanced?

Vincristine is one of the most widely used and more effective drugs in paediatric oncology. The dose-limiting toxicity of neuropathy, lack of proven neuroprotective measures and an incomplete understanding of the pharmacokinetics and pharmacogenetics of vincristine have limited its therapeutic potential. Recent advances in the understanding of vincristine pharmacokinetics and pharmacogenetics, and potential methods of preventing neurotoxicity are reviewed which could enable dose escalation and dose individualisation in order to enhance the therapeutic index.

Treatment of intestinal and hepatic mucormycosis in an immunocompromized child

During ALL chemotherapy, a 4-year-old patient presented with febrile neutropenia and abdominal pain. Ultrasound examinations were repeatedly normal. Computerized tomography on day 7 demonstrated appendicitis and multiple hepatic foci identified as mucormycosis (Absidia corymbifera). Successful outcome was achieved by aggressive re-surgery, long-term antifungal therapy with serum level-monitored posaconazole, and recovery of neutrophil counts. Considering the interference of posaconazole with CYP3A4, vincristine was administered during 72 hr posaconazole windows. Pediatric intestinal mucormycosis, still associated with a >70% case-fatality rate, calls for early imaging and surgery to establish the diagnosis, reduce the fungal mass, and provide a rationale for using posaconazole.

Posaconazole-increased vincristine neurotoxicity in a child: a case report

A 9-year-old girl was managed according to the COPRALL 04 protocol for treatment of a relapse of acute lymphoblastic leukemia. Owing to a previous case of disseminated fusariosis, posaconazole was started 5 days before initiation of chemotherapy. Six days after the last dose of vincristine, the child reported symptoms of severe peripheral neuropathy, abdominal cramps, and constipation. After this, she developed fluctuations in her level of consciousness and seizures. After cessation of therapy with posaconazole, a complete resolution of the above occurred within 7 days. This case illustrates the possibility of vincristine toxicity exacerbated by coadministration of posaconazole. As posaconazole is an inhibitor of the isoenzyme CYP3A4, interactions with drugs that are metabolized via this pathway, such as vincristine, can be anticipated. Another possibility is that, like itraconazole, posaconazole may also inhibit P-glycoprotein-mediated vincristine efflux. Although case reports of neurotoxicity owing to possible interaction between itraconazole and vincristine exist in the literature, only 1 case report relating to the possible interaction between posaconazole and vincristine exists. Clinicians should be made aware of this possible drug-drug interaction.