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

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.

Antifungal Drugs TDM: Trends and Update

PURPOSE

The increasing burden of invasive fungal infections results in growing challenges to antifungal (AF) therapeutic drug monitoring (TDM). This review aims to provide an overview of recent advances in AF TDM.

METHODS

We conducted a PubMed search for articles during 2016-2020 using "TDM" or "pharmacokinetics" or "drug-drug-interaction" with "antifungal," consolidated for each AF. Selection was limited to English language articles with human data on drug exposure.

RESULTS

More than 1000 articles matched the search terms. We selected 566 publications. The latest findings tend to confirm previous observations in real-life clinical settings. The pharmacokinetic variability related to special populations is not specific but must be considered. AF benefit-to-risk ratio, drug-drug interaction (DDI) profiles, and minimal inhibitory concentrations for pathogens must be known to manage at-risk situations and patients. Itraconazole has replaced ketoconazole in healthy volunteers DDI studies. Physiologically based pharmacokinetic modeling is widely used to assess metabolic azole DDI. AF prophylactic use was studied more for Aspergillus spp. and Mucorales in oncohematology and solid organ transplantation than for Candida (already studied). Emergence of central nervous system infection and severe infections in immunocompetent individuals both merit special attention. TDM is more challenging for azoles than amphotericin B and echinocandins. Fewer TDM requirements exist for fluconazole and isavuconazole (ISZ); however, ISZ is frequently used in clinical situations in which TDM is recommended. Voriconazole remains the most challenging of the AF, with toxicity limiting high-dose treatments. Moreover, alternative treatments (posaconazole tablets, ISZ) are now available.

CONCLUSIONS

TDM seems to be crucial for curative and/or long-term maintenance treatment in highly variable patients. TDM poses fewer cost issues than the drugs themselves or subsequent treatment issues. The integration of clinical pharmacology into multidisciplinary management is now increasingly seen as a part of patient care.

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.