Reversible skeletal disease and high fluoride serum levels in hematologic patients receiving voriconazole

Associations of cumulative voriconazole dose, treatment duration, and alkaline phosphatase with voriconazole-induced periostitis

OBJECTIVE

To investigate the associations of cumulative voriconazole dose, treatment duration, and alkaline phosphatase with voriconazole-induced periostitis.

MATERIALS AND METHODS

One hundred and thirty-one patients with voriconazole use were identified using a clinical informatics tool. Health record data including age, sex, immune status, alkaline phosphatase, voriconazole levels, voriconazole dose, frequency, and treatment duration were collected. Imaging studies during the duration of treatment were reviewed by two radiology trainees and imaging features of voriconazole-induced periostitis were confirmed by a board-certified musculoskeletal radiologist. The length, location in the body, location in the bone, type, and morphology of periostitis lesions were recorded. Incident voriconazole-induced periostitis was defined as new periostitis on imaging after 28 days or more of voriconazole treatment in the absence of an alternative diagnosis. Univariate Firth's logistic regression models were performed using cumulative voriconazole dose, treatment duration, and average ALP as predictors and incident VIP as the outcome.

RESULTS

There were nine patients with voriconazole-induced periostitis and 122 patients without voriconazole-induced periostitis. The most common lesion location in the body was the ribs (37%) and morphology was solid (44%). A 31.5-g increase in cumulative voriconazole dose was associated with 8% higher odds of incident periostitis. Increased treatment duration (63 days) and higher average alkaline phosphatase (50 IU/L) were associated with 7% higher odds of periostitis and 34% higher odds of periostitis, respectively.

CONCLUSION

Increased cumulative voriconazole dose, treatment duration, and average alkaline phosphatase were associated with higher odds of voriconazole-induced periostitis.

Skeletal fluorosis secondary to methoxyflurane use for chronic pain

Skeletal fluorosis is rare and occurs secondary to chronic high amounts of fluoride consumption, manifesting as diffuse osteosclerosis, skeletal pain, connective tissue calcification, and increased fracture risk. Methoxyflurane is a volatile, fluorinated hydrocarbon-inhaled analgesic, and the maximum recommended dose is 15 mL (99.9 % w/w) per wk. A rodent study found increased skeletal fluoride after methoxyflurane exposure. However, skeletal fluorosis secondary to methoxyflurane use in humans has rarely been reported. We present the case of a 47-yr-old female with diffuse osteosclerosis secondary to fluorosis from methoxyflurane use for chronic pain, presenting with 3 yr of generalized bony pain and multiple fragility fractures. Lumbar spine BMD was elevated. CT and radiographs demonstrated new-onset marked diffuse osteosclerosis, with calcification of interosseous membranes and ligaments, and a bone scan demonstrated a grossly increased uptake throughout the skeleton. Biochemistry revealed an elevated alkaline phosphatase and bone turnover markers, mild secondary hyperparathyroidism with vitamin D deficiency, and mild renal impairment. Zoledronic acid, prescribed for presumed Paget's disease, severely exacerbated bony pain. Urinary fluoride was elevated (7.3 mg/L; reference range < 3.0 mg/L) and the patient revealed using methoxyflurane 9 mL per wk for 8 yr for chronic pain. A decalcified bone biopsy revealed haphazardly arranged cement lines and osteocytes lacunae and canaliculi, which was consistent with an osteosclerotic process. Focal subtle basophilic stippling around osteocyte lacunae was suggestive of fluorosis. Although fluorosis is not a histological diagnosis, the presence of compatible histology features was supportive of the diagnosis in this case with clinical-radiological-pathological correlation. Skeletal fluorosis should be considered as a cause of acquired diffuse osteosclerosis. Methoxyflurane should not be recommended for chronic pain. The risk of repeated low-dose exposure to fluoride from methoxyflurane use as analgesia may be greater than expected, and the maximum recommended dose for methoxyflurane may require re-evaluation to minimize skeletal complications.

Abbreviated abstract

Skeletal fluorosis is rare and occurs secondary to chronic high amounts of fluoride consumption, manifesting as diffuse osteosclerosis, skeletal pain, connective tissue calcification, and increased fracture risk. We present the case of a 47-yr-old female with skeletal fluorosis secondary to long-term methoxyflurane for chronic pain. The risk of repeated low-dose exposure to fluoride from methoxyflurane use for analgesia may be greater than expected, and the maximum recommended dose for methoxyflurane may require re-evaluation to minimize skeletal complications.

Thoracic periosteal reaction secondary to voriconazole use in an adult transplant patient

Periosteal reaction may result from multiple causes including infection, trauma, medications, and neoplasms. One important etiology that must be considered in the differential diagnosis of symmetric periosteal reaction, especially in immunocompromised patients, is voriconazole use. We present a case of a 65-year-old man who underwent liver transplantation complicated by acute hypoxic respiratory failure and Aspergillus infection. Long term voriconazole therapy was initiated with resultant development of thoracic periosteal reaction which improved following discontinuation of the medication. Given the preferential upper body distribution of periosteal reaction induced by voriconazole, chest radiologists might be the first ones to recognize this adverse effect.

Voriconazole-induced arthritis, enthesitis and periostitis

Voriconazole is a fluoride-containing anti-fungal. Prolonged exposure can result in fluoride deposition within the bone extracellular matrix, resulting in periostitis and arthritis. We report a patient who developed widespread bony pain and polyarthralgia while on voriconazole therapy for COVID-19-associated pulmonary aspergillosis. No associated autoimmune rheumatic disease or alternative cause was noted. Blood investigations showed elevated total serum alkaline phosphatase, bone-specific ALP and fluoride levels, with normal serum voriconazole levels. A whole body nuclear bone scan showed multifocal periostitis. A diagnosis of voriconazole-induced periostitis and arthritis was made. Complete resolution of clinical symptoms with normalisation of the serum ALP occurred within four weeks of voriconazole cessation. While voriconazole-induced periostitis/arthritis is a recognised phenomenon in solid organ and haematopoietic stem cell transplant patients on long-term voriconazole, this case highlights the importance of having a high index of suspicion in other settings including CAPA. Clinical presentation can be mistaken for bony metastatic disease or other inflammatory arthritis.

Using disproportionality analysis to explore the association between periostitis and triazole antifungals in the FDA Adverse Event Reporting System Database

Though triazole antifungals are the first choice for preventing and treating invasive fungal infections, periostitis caused by voriconazole has been described in emerging case reports; however, no studies exist on this association in real-world clinical settings. Our study aimed to identify the association between periostitis and triazole antifungals by analyzing data from the FDA Adverse Event Reporting System (FAERS). We extracted and analyzed reports on the association between periostitis and triazole antifungals in FAERS from the first quarter of 2004 to the second quarter of 2022 using OpenVigil 2.1. Disproportionality analysis was performed to evaluate the association between periostitis and triazole antifungals, and chi-squared (χ²), relative reporting ratio (RRR), reporting odds ratio (ROR), proportional reporting ratio (PRR), and Bayesian confidence propagation neural networks (BCPNN) of information components (IC) were reported. In total, 143 patients experienced periostitis while using voriconazole. Disproportionality analysis identified an association between periostitis and voriconazole (χ² = 82,689.0, RRR = 583.6, 95%CI [472.4, 721.1], PRR = 1808.9, 95%CI [1356.0, 2412.9], ROR = 1831.7, 95%CI [1371.6, 2446.3], IC = 9.2, 95%CI [8.6, 9.8]). However, no safety signals were observed between periostitis and other triazole antifungals. When stratified by sex and age, disproportionality analysis identified positive signals between periostitis and voriconazole. The possible association between periostitis and voriconazole should attract sufficient attention in clinical practice. Alternative treatment with other triazole antifungals can be considered, and causality needs to be verified in further prospective studies.

Systemic Antifungal Therapy for Invasive Pulmonary Infections

Antifungal therapy for pulmonary fungal diseases is in a state of flux. Amphotericin B, the time-honored standard of care for many years, has been replaced by agents demonstrating superior efficacy and safety, including extended-spectrum triazoles and liposomal amphotericin B. Voriconazole, which became the treatment of choice for most pulmonary mold diseases, has been compared with posaconazole and itraconazole, both of which have shown clinical efficacy similar to that of voriconazole, with fewer adverse events. With the worldwide expansion of azole-resistant Aspergillus fumigatus and infections with intrinsically resistant non-Aspergillus molds, the need for newer antifungals with novel mechanisms of action becomes ever more pressing.

Voriconazole-induced periostitis post lung transplantation

Voriconazole is a broad-spectrum triazole antifungal used to treat invasive fungal infections. It is commonly used prophylactically in immunocompromized patient cohorts, including transplant recipients. Diffuse periostitis is a very rare complication of chronic voriconazole use. It is associated with diffuse bone pain, elevated serum alkaline phosphatase and fluorine levels. Characteristic imaging findings include periosteal thickening with a dense, nodular, irregular and often bilateral pattern. We describe the case of a 71-year-old female who presented with multifocal bone pain six years following double lung transplantation. Her post transplantation course had been complicated by a life threatening episode of sepsis secondary to Scedosporium apiospermum, a rare invasive fungal infection following which lifelong prophylaxis with oral Voriconazole was commenced. We discuss the characteristic clinical and imaging manifestations of this rare condition.

Spectrum of voriconazole-associated periostitis in clinical characteristics, diagnosis and management

PURPOSE

Previous knowledge about the relationship between voriconazole exposure and periostitis was mainly based on limited case reports and few retrospective studies. The purpose of this study was to assess the clinical characteristics, diagnosis and management of voriconazole-associated periostitis.

METHODS

Case reports and case series from 1998 to November 30, 2021 on periostitis induced by voriconazole were collected for retrospective analysis.

RESULTS

Forty four patients (18 male and 26 female) from 34 studies were included in total. The median age was 58 years (29-74). The majority of patients had undergone organ transplantation (50.0%) or suffered from hematologic malignancy (31.81%). The median onset time of symptoms was 6 months after the start of voriconazole. The most common initial symptom was diffuse skeletal pain (68.28%) which can be severe and even disabling (66.7%). Ribs (37.21%), femurs (32.56%), scapulae (25.58%), humerus (23.26%), and clavicle (23.26%) were the common involved locations. Most cases were accompanied by different degrees of elevated serum alkaline phosphatase and fluoride level, while some presented with elevated bone-specific alkaline phosphatase. The main radiological features included periosteal reaction and multifocal high radiotracer uptake on bone scintigraphy. The formation of new bone was characterized with bilateral, irregular, nodular, as well as high density. The resolution of symptoms was observed with discontinuation of voriconazole in all patients, of whom 18 patients (52.94%) were relieved within a week. Itraconazole, posaconazole or isavuconazole were safe alternatives to voriconazole in voriconazole-induced periostitis.

CONCLUSION

Voriconazole-induced periostitis is an infrequent complication characterized by bone inflammation involving one or multiple skeletal areas. Bony pain, elevated serum alkaline phosphatase as well as fluoride level are suspicious signs during voriconazole treatment.

Fluoride Pharmacokinetics in Urine and Plasma Following Multiple Doses of MK-8507, an Investigational, Oral, Once-Weekly Nonnucleoside Reverse Transcriptase Inhibitor

MK-8507 is an investigational HIV-1 nonnucleoside reverse transcriptase inhibitor being developed for the treatment of HIV-1 infection. MK-8507 contains 2 trifluoromethyl groups that may result in fluoride release through metabolism, but the extent of MK-8507-related fluoride release in humans has yet to be determined. This double-blind, placebo-controlled, 2-period, parallel-group, multiple-dose trial in healthy participants without HIV-1 who were administered a fluoride-restricted diet and once-weekly doses of MK-8507 aimed to estimate the relationship between MK-8507 dose and fluoride exposure. A total of 15 adult male and 3 adult female (of non-childbearing potential) participants were randomized to receive MK-8507 200 mg (n = 6), MK-8507 800 mg (n = 6), or placebo (n = 6). Change from baseline in mean daily fluoride excretion averaged over 7 days following the administration of MK-8507 200 mg resulted in a net mean increase of 19.8 μmol (90% confidence interval, 12.2-27.4) relative to placebo and did not exceed 57 μmol, a threshold related to the mean difference between the daily reference dose set by the US Environmental Protection Agency and the average dietary fluoride intake in the United States. However, daily urinary fluoride excretion exceeded the threshold following administration of 800 mg MK-8507 (75.1 μmol [90% confidence interval, 67.5-82.7]). Assuming a linear relationship between MK-8507 dose and estimated mean daily fluoride released at steady-state, data interpolation suggests that the US Environmental Protection Agency reference dose for fluoride would not be exceeded in most patients when administering MK-8507 at doses currently under clinical investigation (≤400 mg once weekly).

Consensus guidelines for optimising antifungal drug delivery and monitoring to avoid toxicity and improve outcomes in patients with haematological malignancy and haemopoietic stem cell transplant recipients, 2021

Antifungal agents can have complex dosing and the potential for drug interaction, both of which can lead to subtherapeutic antifungal drug concentrations and poorer clinical outcomes for patients with haematological malignancy and haemopoietic stem cell transplant recipients. Antifungal agents can also be associated with significant toxicities when drug concentrations are too high. Suboptimal dosing can be minimised by clinical assessment, laboratory monitoring, avoidance of interacting drugs, and dose modification. Therapeutic drug monitoring (TDM) plays an increasingly important role in antifungal therapy, particularly for antifungal agents that have an established exposure-response relationship with either a narrow therapeutic window, large dose-exposure variability, cytochrome P450 gene polymorphism affecting drug metabolism, the presence of antifungal drug interactions or unexpected toxicity, and/or concerns for non-compliance or inadequate absorption of oral antifungals. These guidelines provide recommendations on antifungal drug monitoring and TDM-guided dosing adjustment for selected antifungal agents, and include suggested resources for identifying and analysing antifungal drug interactions. Recommended competencies for optimal interpretation of antifungal TDM and dose recommendations are also provided.

Voriconazole‐Associated Periostitis: New Insights into Pathophysiology and Management

Voriconazole‐associated periostitis (VAP) is an underrecognized and unpredictable side effect of long‐term voriconazole therapy. We report two cases of VAP occurring in the post‐transplant setting: a 68‐year‐old lung transplant recipient who required ongoing voriconazole therapy, in whom urinary alkalinization was used to promote fluoride excretion and minimize voriconazole‐related skeletal toxicity, and a 68‐year‐old stem‐cell transplant recipient with a high voriconazole dose requirement, identified on pharmacogenomic testing to be a CYP2C19 ultrarapid metabolizer, the dominant enzyme in voriconazole metabolism. This is the first reported case of pharmacogenomic profiling in VAP and may explain the variability in individual susceptibility to this uncommon adverse effect. Our findings provide new insights into both the management and underlying pathophysiology of VAP. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Voriconazole-associated periostitis: Pathophysiology, risk factors, clinical manifestations, diagnosis, and management

Voriconazole use has been associated with osteoarticular pain and periostitis, likely due to high fluoride content in the drug formulation. This phenomenon has been described primarily with high dosage or prolonged course of voriconazole therapy in immunocompromised and transplant patient populations. Patients typically present with diffuse bony pains associated with elevated serum alkaline phosphatase and plasma fluoride levels in conjunction with radiographic findings suggestive of periostitis. We provide a comprehensive review of the literature to highlight salient characteristics commonly associated with voriconazole-induced periostitis.

A Phase 1 Trial to Evaluate the Relationship Between Fluoride Intake and Urinary Fluoride Excretion in Healthy Participants

Chronic overexposure to fluoride can have deleterious effects in the musculoskeletal system. Some fluorine‐containing therapeutics, such as voriconazole, release fluoride through metabolism. Therefore, drug‐related fluoride exposure should be assessed for novel therapeutics suspected of releasing fluoride through metabolism. Two trials were conducted to identify the optimal method of assessing drug‐related fluoride exposure. In trial 1, designed to assess reproducibility of fluoride pharmacokinetics in urine and plasma, 14 participants were administered a fluoride‐restricted diet and once‐daily doses of sodium fluoride (2.2 mg [1 mg of fluoride] on days 1 and 2; and 13.2 mg of sodium fluoride [6 mg of fluoride] on days 3 and 4). In trial 2, designed to confirm the selected method for fluoride detection, 12 participants were administered a fluoride‐restricted diet and randomized to receive voriconazole (400 mg twice, 12 hours apart, on day 1 [131 mg/d of fluoride maximum], then 3 doses of 200 mg every 12 hours [65.3 mg/d of fluoride maximum]) or placebo. Plasma fluoride concentrations and urinary fluoride excretion were assessed in each trial. Assessment of plasma fluoride concentrations in trial 1 was limited by 301 of 854 samples (35.2%) below the lower limit of quantitation. Urine fluoride excretion was readily measured and demonstrated a decrease from baseline during the fluoride‐restricted diet phase, as well as dose‐proportional increases with fluoride administration. In trial 2, increases in urine fluoride were successfully observed in participants administered voriconazole. In conclusion, fluoride exposure was optimally assessed by urinary fluoride excretion in conjunction with strict dietary fluoride restrictions, as measurements were consistent and reproducible.

Voriconazole-induced periostitis

Voriconazole is a fluorinated drug from the triazole group that is widely used in the prophylaxis and treatment of fungal infections in immunosuppressed patients. Chronic use of this medication can generate, as an adverse effect, a multifocal, asymmetric, diffuse and nodular periosteal reaction, associated with severe and disabling skeletal pain and elevated alkaline phosphatase and serum fluoride. Radiography is the imaging technique of choice for periostitis diagnosis. In general, clinical manifestations and radiographic findings disappear, when the drug is discontinued. We report the clinical case of a 44 year-old woman diagnosed with acute myeloid leukemia, who developed an invasive fungal infection treated with voriconazole after a stem cell transplant. Nine months after starting antifungal treatment, she manifested symptoms and radiological signs compatible with periostitis. Due to clinical suspicion, we decided to suspend voriconazole, with consequent resolution of clinical manifestations and radiological findings.

Review of Pharmacologic Considerations in the Use of Azole Antifungals in Lung Transplant Recipients

Mold-active azole antifungals are commonly prescribed for the prevention of invasive fungal infections in lung transplant recipients. Each agent exhibits a unique pharmacologic profile, an understanding of which is crucial for therapy selection and optimization. This article reviews pharmacologic considerations for three frequently-used azole antifungals in lung transplant recipients: voriconazole, posaconazole, and isavuconazole. Focus is drawn to analysis of drug-interactions, adverse drug reactions, pharmacokinetic considerations, and the role of therapeutic drug monitoring with special emphasis on data from the post-lung transplant population.

Bone Health Management After Hematopoietic Cell Transplantation: An Expert Panel Opinion from the American Society for Transplantation and Cellular Therapy

Bone health disturbances commonly occur after hematopoietic cell transplantation (HCT) with loss of bone mineral density (BMD) and avascular necrosis (AVN) foremost among them. BMD loss is related to pretransplantation chemotherapy and radiation exposure and immunosuppressive therapy for graft-versus-host-disease (GVHD) and results from deficiencies in growth or gonadal hormones, disturbances in calcium and vitamin D homeostasis, as well as osteoblast and osteoclast dysfunction. Although the pathophysiology of AVN remains unclear, high-dose glucocorticoid exposure is the most frequent association. Various societal treatment guidelines for osteoporosis exist, but the focus is mainly on menopausal-associated osteoporosis. HCT survivors comprise a distinct population with unique comorbidities, making general approaches to bone health management inappropriate in some cases. To address a core set of 16 frequently asked questions (FAQs) relevant to bone health in HCT, the American Society of Transplant and Cellular Therapy Committee on Practice Guidelines convened a panel of experts in HCT, adult and pediatric endocrinology, orthopedics, and oral medicine. Owing to a lack of relevant prospective controlled clinical trials that specifically address bone health in HCT, the answers to the FAQs rely on evidence derived from retrospective HCT studies, results extrapolated from prospective studies in non-HCT settings, relevant societal guidelines, and expert panel opinion. Given the heterogenous comorbidities and needs of individual HCT recipients, answers to FAQs in this article should be considered general recommendations, with good medical practice and judgment ultimately dictating care of individual patients. Readers are referred to the Supplementary Material for answers to additional FAQs that did not make the core set.

Considerations for Medications Commonly Utilized in the Oncology Population in the Intensive Care Unit

An increasing number of oncologic patients are presenting to the intensive care unit with complications from both their chronic disease states and cancer therapies due to improved survival rates. The management of these patients is complex due to immunosuppression (from the malignancy and/or treatment), metabolic complications, and diverse medication regimens with the potential for significant drug-drug interactions and overlapping adverse effects. This chapter will provide clinicians with an overview of non-chemotherapy medications frequently encountered in the critically ill oncologic patient, with a focus on practical considerations.

Current Concepts and Future Directions in the Pharmacology and Treatment of Coccidioidomycosis

Coccidioidomycosis remains a significant clinical problem with substantial morbidity and mortality. The vast majority of infections are asymptomatic and the need for early primary therapy remains controversial. The use of triazole antifungals has improved tolerability of therapy but concerns about acute and long-term toxicities among available agents limit their use. In addition, recent findings of decreased in vitro fluconazole susceptibility to as many as 37% of Coccidioides spp. isolates raises concerns regarding optimal therapy for these infections as fluconazole is commonly used for therapy including central nervous system disease. Thus, new agents from novel antifungal classes are currently in preclinical and clinical development aimed at reducing toxicity and improving outcomes of these serious infections.

Voriconazole-Induced Periostitis After Allogeneic Stem Cell Transplantation

A 34-year-old man with history of Hodgkin lymphoma presented 7 months after allogeneic stem cell transplantation with an unexplained severe musculoskeletal pain syndrome. A Tc-MDP bone SPECTCT showed multiple foci with moderate to intense bone uptake across the axial and appendicular skeleton consistent with periostitis. The patient had been on voriconazole daily for 4 months to treat an Aspergillus pneumonia, and in the absence of other causes, a drug-induced periostitis was suspected. Voriconazole was changed to posaconazole with complete resolution of the musculoskeletal symptoms within 3 weeks.

Impairing fluoride export of Aspergillus fumigatus mitigates its voriconazole resistance

Fungi have evolved specific export activities to balance intracellular levels of the toxic ion fluoride, while the first-line antimycotic voriconazole contains fluorine. This study aimed to explore whether impaired fluoride export might result in altered susceptibilities of the human pathogenic mould Aspergillus fumigatus towards this antifungal compound. Functional characterization of the putative fluoride exporter in A. fumigatus was performed in the context of azole resistance by generating deletion strains that were assessed for their resistance against fluoride and voriconazole. The FexA fluoride exporter of A. fumigatus appears to be expressed constitutively, and targeting its encoding gene results in significantly increased sensitivity towards this halide. Impaired fluoride export correlates with increased susceptibility of an azole-resistant fexAΔ strain. These results demonstrate that the fexA-encoded gene product is the major fluoride export activity of A. fumigatus, and that voriconazole serves as a source of fluoride. However, these data do not support the application of voriconazole based on fluoride toxicity.

Spectrum of Voriconazole-Induced Periostitis With Review of the Differential Diagnosis

OBJECTIVE

Voriconazole is an antifungal medication used primarily for the treatment of Candida and Aspergillus infections. A fairly newly described side effect of long-term voriconazole use is periostitis. The purpose of this article is to describe the main differential consideration-hypertrophic osteoarthropathy-and other differential diagnoses, including venous stasis, thyroid acropachy, and hypervitaminosis A.

CONCLUSION

With knowledge of imaging appearance, clinical manifestations, and outcomes, radiologists can make an accurate diagnosis of voriconazole-induced periostitis, and clinical teams can initiate appropriate management.

Diffuse periostitis as the primary presenting radiological finding in an AML patient with disease relapse

Acute myelogenous leukemia is a hematologic malignancy defined by the presence of myeloid blasts causing bone marrow infiltration. Evaluation and workup of acute myelogenous leukemia is based on comprehensive medical history, physical examination, laboratory evaluation, and bone marrow sampling. Magnetic resonance (MR) imaging is the study of choice in the evaluation of this disease including the initial evaluation, treatment follow-up, and complications. Herein, we report a case of relapse of the acute myelogenic leukemia in an adult patient who presented with diffuse periostitis in his lower extremities diagnosed on MR imaging and confirmed on Technetium bone scan, which also showed periostitis along the bilateral humeri. To our knowledge, this was not previously reported in the English literature.

A vexing case of bone pain in a renal transplant recipient: Voriconazole-induced periostitis

Immunosuppression increases the risk of opportunistic infections including fungal infections in solid organ transplant recipients. Voriconazole is used to treat invasive aspergillus infections but prolonged usage may rarely lead to periostitis. Increased plasma fluoride concentration leading to osteoblastic upregulation is thought to be the catalyst, and symptom reversal occurs with discontinuation of the offending agent. A renal transplant recipient who was on voriconazole for invasive aspergillosis developed diffuse debilitating symmetrical bone pain. Having ruled out other neurological, metabolic, and drug etiologies, voriconazole-induced periostitis was diagnosed. Increased plasma fluoride level was documented, but bone scan was non-specific. A therapeutic discontinuation of voriconazole and switch to posaconazole provided rapid symptom resolution. The patient accidently restarted voriconazole as an outpatient resulting in the same symptomology, and thus provided further evidence that this was drug related. Voriconazole-induced periostitis is a described entity in immunosuppressed solid organ transplant patients who are treated with a prolonged course of voriconazole. This case study is novel in that it demonstrates drug induced periostitis in a renal transplant recipient who developed debilitating periostitis within a short time after starting voriconazole and equally rapid resolution once it was discontinued. We conclude that patients treated with voriconazole should be routinely monitored for periostitis.

Prolonged voriconazole treatment in a patient with chronic lymphocytic leukemia resulting in a litany of chronic overlapping toxicities

Voriconazole is a triazole antifungal with activity against a number of yeast and mold species including Candida, Aspergillosis, Fusarium, and Coccidioides. Invasive fungal infections are associated with high morbidity and mortality, prolonged treatment courses, and occasionally lifelong suppressive therapy. Voriconazole therapy can result in a number of acute toxicities that clinicians are frequently aware of including hepatotoxicity, visual disturbances, and hallucinations; however, there is limited experience with extended durations of voriconazole therapy. We describe the case of a 62-year-old man who developed Coccidioides meningitis as a result of prolonged neutropenia from treatment for chronic lymphocytic leukemia. He was initially treated with a number of different antifungal agents including voriconazole, liposomal amphotericin B, fluconazole, and itraconazole; however, he developed acute toxicity due to those agents. He was successfully re-challenged with voriconazole, and maintained therapeutic serum concentrations throughout treatment. As a result of prolonged voriconazole exposure of over 14 years, he has suffered a number of toxicities, most significantly including actinic keratosis, squamous cell carcinoma, and skeletal fluorosis. To our knowledge, this is the longest continuous use of voriconazole therapy currently in the literature.

Voriconazole-induced periostitis deformans: serial imaging in a patient with ANCA vasculitis

OBJECTIVES

A 61-year-old with acute granulomatosis and polyangiitis developed Aspergillus fumigatus pneumonia after admission to the intensive care unit with a small bowel perforation. This occurred after immunosuppression (intravenous methylprednisolone, intravenous cyclophosphamide, and plasmapheresis) for his initial presentation with stage 3 acute kidney injury.

MATERIALS AND METHODS

The mycologist recommended long-term treatment with voriconazole after initial recovery.

RESULTS

After 7 months of treatment, the patient complained of joint pain and swelling in his hands. Radiographs, computed tomography, and single-photon emission computed tomography appearances were consistent with periostitis. A diagnosis of Voriconazole-induced periostitis deformans was made and the voriconazole was stopped. Plasma fluoride level was 278 μg/L (normal range < 50 μg/L). Discontinuation of voriconazole led to clinical improvement.

CONCLUSIONS

Periostitis deformans due to fluorosis is a rare complication of voriconazole treatment. The imaging in our case is unusually dramatic. We were able to track the evolution of periosteal reactions over serial imaging.

Fungal Infections Associated with Contaminated Steroid Injections

In mid-September 2012, the largest healthcare-associated outbreak in U.S. history began. Before it was over, 751 patients were reported with fungal meningitis, stroke, spinal or paraspinal infection, or peripheral osteoarticular infection, and 64 (8.5%) died. Most patients had undergone epidural injection, and a few osteoarticular injection, of methylprednisolone acetate that had been manufactured at the New England Compounding Center (NECC). The offending pathogen in most cases was Exserohilum rostratum, a brown-black soil organism that previously was a rare cause of human infection. Three lots of methylprednisolone were contaminated with mold at NECC; the mold from unopened bottles of methylprednisolone was identical by whole-genome sequencing to the mold that was isolated from ill patients. Early cases manifested as meningitis, some patients suffered posterior circulation strokes, and later cases were more likely to present with localized infection at the injection site, including epidural abscess or phlegmon, vertebral diskitis or osteomyelitis, and arachnoiditis with intradural involvement of nerve roots. Many patients with spinal or paraspinal infection required surgical intervention. Recommendations for treatment evolved over the first few weeks of the outbreak. Initially, combination therapy with liposomal amphotericin B and voriconazole was recommended for all patients; later, combination therapy was recommended only for those who were most ill, and voriconazole monotherapy was recommended for most patients. Among those patients who continued antifungal therapy for at least 6 months, outcomes for most appeared to be successful, although a few patients remain on therapy.

The anti-Aspergillus drug pipeline: Is the glass half full or empty?

Aspergillosis has emerged as important human mycoses, in view of the ever expanding population at risk. The emergence of resistance to the most commonly used drugs for aspergillosis, the azoles, the mediocre activity, and frequent toxicity of the current antifungal armamentarium, support the need for development of novel antifungals for treatment of this disease. In this minireview, we describe recent efforts by small drug companies and University research labs to develop novel therapies for invasive aspergillus infections. We specifically discuss four small-molecule antifungals (T-2307, E1210/APX001, ASP2397, and F901318) with novel modes-of-action, which are currently entering phase I clinical trials. In addition, we provide a nonexhaustive discussion of some interesting, yet early developments in the quest for improved therapeutic strategies such as (i) novel formulations of amphotericin B including AMB nanoparticle suspensions and AMB-arabinogalactan or AMB-PEG conjugates that show low toxicity and high efficacy in preclinical animal models, (ii) repurposed drugs that synergize with existing antifungals (clozafimine, trichostatin A, MGCD290, geldanamycin, tacrolimus, cyclosporin), (iii) natural products (psoriasin, humidimycin), and (iv) immunotherapy using adoptive transfer of activated immune cells with antifungal activity. We argue that despite the plethora of candidates, the extremely low success rates of drug development leading to clinically useful drugs reinforces the need for continued clinical reliance on mainstream antifungals and their improved derivatives.

An update on the safety and interactions of antifungal drugs in stem cell transplant recipients

INTRODUCTION

Invasive fungal diseases (IFDs) are a major cause of morbidity and mortality in patients undergoing allogeneic hematopoietic stem cell transplant (HSCT). Improvement in the management of IFDs have been achieved with the availability of new effective and safe antifungal drugs, however, many of these newer treatments have some limitations in their variable toxicity and unique predisposition for pharmacokinetic drug-drug interactions. Areas covered: This article is an update of a previous review published in this journal evaluating the safety profile of the antifungal drugs. Interesting new features include the availability of the new drug isavuconazole and the new tablet and intravenous formulations of posaconazole. Different dosages and new ways of administration of liposomal Amphotericin B (L-AmB) and echinocandins may be considered in the HSCT practice. Expert opinion: Nephrotoxicity continues to be a clinically relevant and frequent side effect of L-AmB which may cause a reduced clearance of other renally eliminated drugs frequently used in HSCT patients. Echinocandins are favorable therapeutic options in view of their low toxicity and uncommon drug-drug interactions. Important limitations of triazoles are represented by hepatic toxicity and certain side effects particularly after prolonged treatments. The new triazole isavuconazole and the new tablet formulation of posaconazole will be probably increasingly used in the HSCT setting not only due to their efficacy but in particular for their interesting toxicity profile and pharmacokinetic characteristics. The knowledge of these pharmacological findings is crucial in the daily care of allogeneic HSCT patients.

Voriconazole-Induced Periostitis & Enthesopathy in Solid Organ Transplant Patients: Case Reports

Background

Voriconazole is frequently used to treat fungal infections in solid organ transplant patients. Recently, there have been reports suggesting that prolonged voriconazole therapy may lead to periostitis.

Aim

Here we present two cases of voriconazole-induced periostitis in solid organ transplant patients.

Case Presentation

Voriconazole was given to two transplant patients-one with a liver transplant and the second with a heart transplant, to treat their fungal infections. Both developed voriconazole-induced toxicity. While undergoing voriconazole therapy, they had incapacitating bone pain. The liver transplant patient had to be taken off voriconazole, and the heart transplant patient succumbed to non-voriconazole related causes.

Conclusions

Voriconazole therapy in two solid organ transplant patients resulted in periostitis. We provide potential etiologies underlying voriconazole-induced periostitis, including fluoride toxicity, abnormalities in the pulmonary vascular bed leading to the production of downstream inflammatory mediators, and abnormal pharmacokinetics of hepatic drug metabolism. In addition to monitoring blood voriconazole trough levels, we suggest careful assessment for musculoskeletal pain in patients undergoing voriconazole treatment for two months or more, particularly if their daily dosages of voriconazole exceed 500 mg per day. Appropriate workup should include measurement of alkaline phosphatase, voriconazole trough and fluoride levels as well as a bone scan. Overall, early recognition of voriconazole-induced musculoskeletal toxicity is important for better morbidity outcomes.

Arterial calcification due to CD73 deficiency (ACDC): imaging manifestations of ectopic mineralization

Arterial calcification due to CD73 deficiency (ACDC) is a recently identified rare and debilitating adult-onset disorder caused by autosomal recessive NT5E gene mutations. ACDC is characterized by progressive and painful arterial calcifications primarily affecting the lower extremities, as well as calcifications affecting small joint capsules of the hands and feet. In this case report, the authors provide clinical follow-up for one of the first individuals identified by the National Institutes of Health (NIH) as having ACDC, focusing mainly on the imaging manifestations of periarticular joint mineralization, which are bilateral but slightly asymmetric, bulky up to the levels of the metacarpophalangeal and metatarsophalangeal joints, but smaller and more capsular in distribution at the proximal and distal interphalangeal joints, without erosive change or intra-articular mineralization. Differential considerations for similar appearing joint mineralization are provided.

Practice Guidelines for the Diagnosis and Management of Aspergillosis: 2016 Update by the Infectious Diseases Society of America

It is important to realize that guidelines cannot always account for individual variation among patients. They are not intended to supplant physician judgment with respect to particular patients or special clinical situations. IDSA considers adherence to these guidelines to be voluntary, with the ultimate determination regarding their application to be made by the physician in the light of each patient's individual circumstances.

Voriconazole-Induced Periostitis Mimicking Chronic Graft-versus-Host Disease after Allogeneic Stem Cell Transplantation

Voriconazole is an established first-line agent for treatment of invasive fungal infections in patients undergoing allogeneic stem cell transplantation (ASCT). It is associated with the uncommon complication of periostitis. We report this complication in a 58-year-old female undergoing HSCT. She was treated with corticosteroids with minimal improvement. The symptoms related to periostitis can mimic chronic graft-versus-host disease in patients undergoing HSCT and clinicians should differentiate this from other diagnoses and promptly discontinue therapy.

Voriconazole-induced periostitis: beyond post-transplant patients

Voriconazole-induced periostitis (VIP) is a rare but increasingly encountered entity since Food and Drug Administration (FDA) approval of the second generation antifungal medication in 2002. Literature reports most commonly include transplant recipients on immunosuppressive therapy simultaneously requiring antifungal therapy. Nontransplant patients receiving long-term voriconazole have an equal risk of developing the disease, but may experience a delay in diagnosis due to a lack of familiarity with the process outside of the post-transplant and/or immunosuppressed population. We present a case of VIP in a nontransplant, immunocompetent patient on suppressive antifungal therapy for prior abdominal aortic stent graft fungal infection. Radiologist review of current medications and recognition of periostitis on multiple imaging modalities may hasten the diagnosis and lead to earlier treatment and resolution of symptoms.

Risk Assessment of Fluoride Intake from Tea in the Republic of Ireland and its Implications for Public Health and Water Fluoridation

The Republic of Ireland (RoI) is the only European Country with a mandatory national legislation requiring artificial fluoridation of drinking water and has the highest per capita consumption of black tea in the world. Tea is a hyperaccumulator of fluoride and chronic fluoride intake is associated with multiple negative health outcomes. In this study, fifty four brands of the commercially available black tea bag products were purchased and the fluoride level in tea infusions tested by an ion-selective electrode method. The fluoride content in all brands tested ranged from 1.6 to 6.1 mg/L, with a mean value of 3.3 mg/L. According to our risk assessment it is evident that the general population in the RoI is at a high risk of chronic fluoride exposure and associated adverse health effects based on established reference values. We conclude that the culture of habitual tea drinking in the RoI indicates that the total cumulative dietary fluoride intake in the general population could readily exceed the levels known to cause chronic fluoride intoxication. Evidence suggests that excessive fluoride intake may be contributing to a wide range of adverse health effects. Therefore from a public health perspective, it would seem prudent and sensible that risk reduction measures be implemented to reduce the total body burden of fluoride in the population.

Correlation of Pain and Fluoride Concentration in Allogeneic Hematopoietic Stem Cell Transplant Recipients on Voriconazole

Supportive care guidelines recommend antimold prophylaxis in hematopoietic stem cell transplant (HSCT) recipients deemed to have high risk for invasive fungal infection, leading to long-term use of voriconazole after allogeneic HSCT in patients who remain immunocompromised. Voriconazole has been associated with periostitis, exostoses, and fluoride excess in patients after solid organ transplantation, HSCT, and leukemia therapy. The aims of this study were to describe the frequency and clinical presentation of patients presenting with pain and fluoride excess among allogeneic HSCT patients taking voriconazole, to identify when a plasma fluoride concentration was measured with respect to voriconazole initiation and onset of pain, and to describe the outcomes of patients with fluoride excess in the setting of HSCT. A retrospective review was conducted of all adult allogeneic HSCT patients receiving voriconazole at Mayo Clinic in Rochester, Minnesota, between January 1, 2009 and July 31, 2012. Of 242 patients included, 32 had plasma fluoride measured to explore the etiology of musculoskeletal pain. In 31 patients with fluoride measurement while on voriconazole, 29 (93.5%) had elevated levels. The median plasma fluoride was 11.1 μmol/L (range, 2.4 to 24.7). The median duration of voriconazole was 163 days (range, 2 to 1327). The median time to fluoride measurement was 128 days after voriconazole initiation (range, 28 to 692). At 1 year after the start of voriconazole after HSCT, 15.3% of patients had developed pain associated with voriconazole use and 35.7% developed pain while on voriconazole after 2 years. Of the patients with an elevated fluoride level, 22 discontinued voriconazole; pain resolved or improved in 15, stabilized in 3, and worsened in 4 patients. Ten patients continued voriconazole; pain resolved or improved in 7, was attributable to alternative causes in 2, and undefined in 1. Serum creatinine, estimated glomerular filtration rate, alkaline phosphatase, and voriconazole concentration did not predict for fluoride excess and associated pain. Periostitis due to fluoride excess is a common adverse effect of voriconazole that should be considered in patients presenting with pain and is often reversible after drug discontinuation. Alternative antifungal agents with a lower risk for fluoride excess should be considered in patients receiving voriconazole who develop fluoride excess and pain.

Voriconazole Enhances the Osteogenic Activity of Human Osteoblasts In Vitro through a Fluoride-Independent Mechanism

Periostitis, which is characterized by bony pain and diffuse periosteal ossification, has been increasingly reported with prolonged clinical use of voriconazole. While resolution of clinical symptoms following discontinuation of therapy suggests a causative role for voriconazole, the biological mechanisms contributing to voriconazole-induced periostitis are unknown. To elucidate potential mechanisms, we exposed human osteoblasts in vitro to voriconazole or fluconazole at 15 or 200 μg/ml (reflecting systemic or local administration, respectively), under nonosteogenic or osteogenic conditions, for 1, 3, or 7 days and evaluated the effects on cell proliferation (reflected by total cellular DNA) and osteogenic differentiation (reflected by alkaline phosphatase activity, calcium accumulation, and expression of genes involved in osteogenic differentiation). Release of free fluoride, vascular endothelial growth factor (VEGF), and platelet-derived growth factor (PDGF) was also measured in cell supernatants of osteoblasts exposed to triazoles, with an ion-selective electrode (for free fluoride) and enzyme-linked immunosorbent assays (ELISAs) (for VEGF and PDGF). Voriconazole but not fluconazole significantly enhanced the proliferation and differentiation of osteoblasts. In contrast to clinical observations, no increases in free fluoride levels were detected following exposure to either voriconazole or fluconazole; however, significant increases in the expression of VEGF and PDGF by osteoblasts were observed following exposure to voriconazole. Our results demonstrate that voriconazole can induce osteoblast proliferation and enhance osteogenic activity in vitro. Importantly, and in contrast to the previously proposed mechanism of fluoride-stimulated osteogenesis, our findings suggest that voriconazole-induced periostitis may also occur through fluoride-independent mechanisms that enhance the expression of cytokines that can augment osteoblastic activity.

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.