Safety, Tolerance, and Efficacy of Posaconazole Therapy in Patients with Nonmeningeal Disseminated or Chronic Pulmonary Coccidioidomycosis

A Prospective Study to Evaluate the Effect of Therapeutic Drug Monitoring-Based Posaconazole Prophylaxis on Invasive Fungal Infection Rate During Acute Myeloid Leukemia Induction Therapy

Invasive fungal infections (IFIs) are a significant cause of morbidity and mortality in de-novo acute myeloid leukemia patients receiving induction chemotherapy. Despite using posaconazole, a broad-spectrum antifungal, for IFI prophylaxis, the breakthrough IFI rate is high in the real-world setting. One of the reasons could be frequent suboptimal plasma posaconazole levels. In the present study, we evaluated if therapeutic drug monitoring (TDM) guided posaconazole prophylaxis can reduce the IFI rates in comparison to a historical cohort. We enrolled 90 patients, > / = 16 years of age, without baseline IFIs, planned for remission induction therapy. All patients were started on posaconazole suspension 200 mg TDS and the dose was increased in a stepwise manner if trough levels were found to be suboptimal (< 350 ng/ml for day 2 or < 700 ng/ml subsequently). The TDM based approach resulted in a significant decline in breakthrough IFI rates (18% versus 52%, P < 0.0001) A total of 69 patients (78%) required dose escalation. Thirty-one patients required change in antifungals due to either suboptimal levels, persistent fever, diarrhoea or vomiting. We could not demonstrate an exposure-response relationship but the difference in IFI rates in patients with a median posaconazole level > / = 700 ng/ml (0%) and < 700 ng/ml (21.6%) was clinically meaningful. Posaconazole levels were found to be significantly lower in patients on antacids and prokinetics. The incidence of posaconazole-related grade 3 toxicity was low (2.3%). Thus TDM-based dosing of posaconazole helps reduce breakthrough IFI rate and should be a part of posaconazole prophylaxis.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12288-023-01709-3.

Genetic and Other Determinants for the Severity of Coccidioidomycosis: A Clinician's Perspective

The endemic fungal infection, coccidioidomycosis, occurs after inhalation of one or very few Coccidioides spp. spores. Infections produce diverse clinical manifestations, ranging from insignificant to extremely destructive, even fatal. Approaches to understanding this range of consequences have traditionally categorized patients into a small number of groups (asymptomatic, uncomplicated self-limited, fibro-cavitary, and extra-thoracic disseminated) and then looked for immunologic differences among them. Recently, variants within genes of innate pathways have been found to account, in part, for infections that result in disseminated disease. This discovery raises the very attractive theory that, in patients without severe immunosuppression, much of the disease spectrum can be accounted for by various combinations of such deleterious variants in innate pathways. In this review, we summarize what is known about genetic determinants that are responsible for the severity of coccidioidal infections and how complex innate genetic differences among different people might account for the spectrum of disease observed clinically.

Osteoarticular Mycoses

Osteoarticular mycoses are chronic debilitating infections that require extended courses of antifungal therapy and may warrant expert surgical intervention. As there has been no comprehensive review of these diseases, the International Consortium for Osteoarticular Mycoses prepared a definitive treatise for this important class of infections. Among the etiologies of osteoarticular mycoses are Candida spp., Aspergillus spp., Mucorales, dematiaceous fungi, non-Aspergillus hyaline molds, and endemic mycoses, including those caused by Histoplasma capsulatum, Blastomyces dermatitidis, and Coccidioides species. This review analyzes the history, epidemiology, pathogenesis, clinical manifestations, diagnostic approaches, inflammatory biomarkers, diagnostic imaging modalities, treatments, and outcomes of osteomyelitis and septic arthritis caused by these organisms. Candida osteomyelitis and Candida arthritis are associated with greater events of hematogenous dissemination than those of most other osteoarticular mycoses. Traumatic inoculation is more commonly associated with osteoarticular mycoses caused by Aspergillus and non-Aspergillus molds. Synovial fluid cultures are highly sensitive in the detection of Candida and Aspergillus arthritis. Relapsed infection, particularly in Candida arthritis, may develop in relation to an inadequate duration of therapy. Overall mortality reflects survival from disseminated infection and underlying host factors.

Targeting an evolutionarily conserved "E-L-L" motif in spike protein to identify a small molecule fusion inhibitor against SARS-CoV-2

As newer variants of SARS-CoV-2 continue to pose major threats to global human health and economy, identifying novel druggable antiviral targets is the key toward sustenance. Here, we identify an evolutionarily conserved "Ex3Lx6L" ("E-L-L") motif present within the HR2 domain of all human and nonhuman coronavirus spike (S) proteins that play a crucial role in stabilizing its postfusion six-helix bundle (6-HB) structure and thus, fusion-mediated viral entry. Mutations within this motif reduce the fusogenicity of the S protein without affecting its stability or membrane localization. We found that posaconazole, an FDA-approved drug, binds to this "E-L-L" motif and impedes the formation of 6-HB, thus effectively inhibiting SARS-CoV-2 infection in cells. While posaconazole exhibits high efficacy in blocking S protein-mediated viral entry, mutations within the "E-L-L" motif rendered the protein completely resistant to the drug, establishing its specificity toward this motif. Our data demonstrate that posaconazole restricts early stages of infection through specific inhibition of membrane fusion and viral genome release into the host cell and is equally effective toward all major variants of concerns of SARS-CoV-2, including Beta, Kappa, Delta, and Omicron. Together, we show that this conserved essential "E-L-L" motif is an ideal target for the development of prophylactic and therapeutic interventions against SARS-CoV-2.

Update on the Epidemiology, Diagnosis, and Treatment of Coccidioidomycosis

Coccidioidomycosis is a fungal infection caused by Coccidioides immitis and Coccidioides posadasii. The dimorphic fungi live in the soils of arid and semi-arid regions of the western United States, as well as parts of Mexico, Central America, and South America. Incidence of disease has risen consistently in recent years, and the geographic distribution of Coccidioides spp. appears to be expanding beyond previously known areas of endemicity. Climate factors are predicted to further extend the range of environments suitable for the growth and dispersal of Coccidioides species. Most infections are asymptomatic, though a small proportion result in severe or life-threatening forms of disease. Primary pulmonary coccidioidomycosis is commonly mistaken for community-acquired pneumonia, often leading to inappropriate antibacterial treatment and unnecessary healthcare costs. Diagnosis of coccidioidomycosis is challenging and often relies on clinician suspicion to pursue laboratory testing. Advancements in diagnostic tools and antifungal therapy developments seek to improve the early detection and effective management of infection. This review will highlight recent updates and summarize the current understanding of the epidemiology, diagnosis, and treatment of coccidioidomycosis.

Targeting an evolutionarily conserved "E-L-L" motif in the spike protein to develop a small molecule fusion inhibitor against SARS-CoV-2

As newer variants of SARS-CoV-2 continue to pose major threats to global human health and economy, identifying novel druggable antiviral targets is the key towards sustenance. Here, we identify an evolutionary conserved E-L-L motif present within the HR2 domain of all human and non-human coronavirus spike (S) proteins that play a crucial role in stabilizing the post-fusion six-helix bundle (6-HB) structure and thus, fusion-mediated viral entry. Mutations within this motif reduce the fusogenicity of the S protein without affecting its stability or membrane localization. We found that posaconazole, an FDA-approved drug, binds to this E-L-L motif resulting in effective inhibition of SARS-CoV-2 infection in cells. While posaconazole exhibits high efficacy towards blocking S protein-mediated viral entry, mutations within the E-L-L motif rendered the protein completely resistant to the drug, establishing its specificity towards this motif. Our data demonstrate that posaconazole restricts early stages of infection through specific inhibition of membrane fusion and viral genome release into the host cell and is equally effective towards all major variants of concerns of SARS-CoV-2 including beta, kappa, delta, and omicron. Together, we show that this conserved essential E-L-L motif is an ideal target for the development of prophylactic and therapeutic interventions against SARS-CoV-2.

Coccidioidomycosis: A Contemporary Review

Coccidioidomycosis, colloquially known as Valley Fever, is an invasive dimorphic fungal infection caused by Coccidioides immitis and C. posadasii. The fungi are found in the arid desert soils of the southwestern US, as well as in parts of Mexico and Central and South America. Acquisition is typically via inhalation of arthroconidia which become airborne after both natural (e.g., earthquakes, dust storms, and fires) and human-related events (e.g., military maneuvers, recreational activities, agriculture, and construction). The incidence of infection in increasing likely a result of both climatic and populational changes. Further, the recognized geographic distribution of Coccidioides spp. is expanding, as cases are being diagnosed in new areas (e.g., eastern Washington, Oregon, and Utah). Most coccidioidal infections are asymptomatic (60%); however, approximately one-third develop a pulmonary illness which is a leading cause of community-acquired pneumonia in highly endemic areas. Uncommonly (0.5–2% of cases), the infection disseminates to extrapulmonary locations (e.g., skin, bones/joints, and the central nervous system), and is most commonly seen among persons with cellular immunodeficiencies (e.g., transplant recipients, HIV, and pregnancy) and non-Caucasian races (especially African Americans and Filipinos). The diagnosis of coccidioidomycosis requires astute clinical suspicion and laboratory findings, including positive serology, cultures, and/or histopathology results. Treatment is warranted among persons with pneumonia who have risk factors for complicated disease and among those with extrapulmonary disease. Novel antifungals with improved fungicidal activity and rapidity of action with fewer side effects and drug interactions are needed. Preventive strategies (e.g., education regarding the disease, dust avoidance, mask wearing, including among select groups, antifungal prophylaxis, and surveillance laboratory testing) are advised for residents and travelers to endemic areas. Currently, no preventive vaccine is available. Coccidioidomycosis has been recognized for over a century, and an expanding wealth of knowledge has been gained regarding this emerging infectious disease which will be reviewed here.

Posaconazole treatment of refractory coccidioidomycosis in dogs

Background

The majority of dogs with coccidioidomycosis recover with administration of fluconazole or itraconazole, although some cases are refractory or the dogs do not tolerate administration of these medications.

Objectives

The objective was to describe the treatment outcomes and therapeutic monitoring of 8 dogs with refractory coccidioidomycosis treated with posaconazole.

Animals

Eight dogs with refractory coccidioidomycosis.

Methods

Retrospective case series. Medical records from Veterinary Specialty Center of Tucson were searched to identify dogs with refractory coccidioidomycosis that were treated with posaconazole. Clinical information and the results of monitoring trough serum posaconazole concentrations were retrieved.

Results

Eight dogs with refractory coccidioidomycosis were treated with 2.5 to 10 mg/kg per day of posaconazole. Six of 8 dogs recovered or developed clinical remission while administered posaconazole. Thirteen serum concentrations from 8 dogs tested were >1 μg/mL (range, 1.52 to >6 μg/mL) and the drug was well‐tolerated by 7 dogs. One dog required dosage reductions and treatment was ultimately discontinued because of hepatotoxicosis.

Conclusions and Clinical Importance

Posaconazole should be considered as a treatment option for dogs with refractory coccidioidomycosis. Monitoring of indicators of liver function or injury along with therapeutic drug monitoring is recommended to tailor dosage in the event of hepatic toxicosis.

Severe Posaconazole-Induced Glucocorticoid Deficiency with Concurrent Pseudohyperaldosteronism: An Unfortunate Two-for-One Special

A 56-year-old Hispanic man with a history of disseminated coccidioidomycosis was diagnosed with persistent glucocorticoid insufficiency and pseudohyperaldosteronism secondary to posaconazole toxicity. This case was notable for unexpected laboratory findings of both pseudohyperaldosteronism and severe glucocorticoid deficiency due to posaconazole’s mechanism of action on the adrenal steroid synthesis pathway. Transitioning to fluconazole and starting hydrocortisone resolved the hypokalemia but not his glucocorticoid deficiency. This case highlights the importance of recognizing iatrogenic glucocorticoid deficiency with azole antifungal agents and potential long term sequalae.

Efficacy and Associated Drug Exposures of Isavuconazole and Fluconazole in an Experimental Model of Coccidioidomycosis

Coccidioides spp. are important pathogens in regions where they are endemic, and new treatment options are needed. Here, isavuconazonium sulfate (ISAVUSULF) and fluconazole (FLU) were evaluated in experimental disseminated coccidioidomycosis to characterize drug exposures associated with efficacy. Broth macrodilution was performed on Coccidioides isolates to measure minimal effective concentrations (MEC) and minimal fungicidal concentrations (MFC). Mice were inoculated with Coccidioides posadasii (Silveira strain). Treatment started 4 days postinoculation. In model 1, mice were treated for 19 days, followed by 30 days of off-therapy observation, measuring survival through day 49 and residual fungal burden. Treatments included ISAVUSULF (prodrug; 186, 279, or 372 mg/kg twice daily), FLU (20 or 100 mg/kg once daily), and no treatment. Model 2 included 7-day treatment with ISAVUSULF (prodrug; 74.4, 111.6, or 148.8 mg/kg twice daily), FLU (20 or 100 mg/kg once daily), and no treatment. Serial plasma and tissues samples were obtained for pharmacokinetics (PK) and fungal burden measurement, respectively. Fifty percent minimal effective concentration (MEC50) values were 0.39 mg/liter (isavuconazole [ISAV]) and 12.5 mg/liter (FLU). Treatment with ISAVUSULF186 or with either FLU dose resulted in higher survival compared to that in the untreated group. Treatment with ISAVUSULF186 or ISAVUSULF279 twice daily or FLU100 reduced fungal burden in all organs (model 1). In model 2, a >1 log10 CFU/organ reduction was demonstrated, with ISAV area under the concentration-time curve (AUC) values achieved with 111.6 mg/kg twice daily (56.8 mg · h/liter) in the spleen and liver. FLU AUC values of 100 and 500 mg·h/liter for 20 and 100 mg/kg doses, respectively, resulted in a >1 log10 CFU/organ mean reduction in all organs. ISAVUSULF and FLU improved survival and reduced fungal burden. Increasing plasma drug exposures resulted in decreases in fungal burden.

Too Much of a Good Thing: Defining Antimicrobial Therapeutic Targets to Minimize Toxicity

Antimicrobials are a common cause of drug toxicity. Understanding the relationship between systemic antimicrobial exposure and toxicity is necessary to enable providers to take a proactive approach to prevent undesired drug effects. When an exposure threshold has been defined that predicts drug toxicity, therapeutic drug monitoring (TDM) can be performed to assure drug exposure does not exceed the defined threshold. Although some antimicrobials have well-defined dose-dependent toxicities, many other exposure-toxicity relationships have either not been well-defined or, in some cases, not been evaluated at all. In this review, we examine the relationship between exposures and toxicities for antibiotic, antifungal, and antiviral agents. Furthermore, we classify these relationships into four categories: known association between drug exposure and toxicity such that clinical implementation of a specific exposure threshold associated with toxicity for TDM is supported (category 1), known association between drug exposure and toxicity but the specific exposure threshold associated with toxicity is undefined (category 2), association between drug exposure and toxicity has been suggested but relationship is poorly defined (category 3), and no known association between drug exposure and toxicity (category 4). Further work to define exposure-toxicity thresholds and integrate effective TDM strategies has the potential to minimize many of the observed antimicrobial toxicities.

Lack of Toxicity With Long-term Isavuconazole Use in Patients With Hematologic Malignancy

Prolonged courses of isavuconazole (ISA) are increasingly utilized in immunocompromised patients. Toxicities have been reported with long-term use of the other triazoles. We report the first real-life tolerability data in 50 patients with hematologic malignancy receiving ≥6 months of ISA. ISA was well tolerated in our ill patient population.

Simultaneous coccidioidomycosis and phaeohyphomycosis in a kidney transplant recipient: A case report and literature review

Advances in solid organ transplantation have improved the survival of end-stage organ disease at the expense of an increased risk for opportunistic infections. Unusual clinical presentations and the possibility of concurrent infections make diagnosing invasive fungal infection (IFI) more difficult. Here, we present a case of simultaneous vertebral infection caused by Coccidioides immitis-posadasii and subcutaneous phaeohyphomycosis due to Nigrograna mackinnonii in a kidney transplant recipient. The diagnosis of both infections required invasive procedures to obtain tissue and a high index of suspicion that more than one IFI could be present. A multidisciplinary team approach for the management of immunocompromised patients with suspected or diagnosed IFI is warranted.

Coccidioides in lung transplant: case report

A middle-aged woman was hospitalised for generalised, painful skin lesions 6 weeks after a successful double-lung transplant. She had end-stage lung disease associated with chronic obstructive pulmonary disease due to alpha-1 antitrypsin deficiency, and she had been treated with itraconazole for 16 months because of lung infection associated with Malbranchea spp. Results of a skin biopsy of the initial lesion on her arm showed non-specific dermal inflammation, presumably due to reactivation of the Malbranchea spp infection. Follow-up cervical lymph node biopsy and culture showed Coccidioides posadasii/C. immitis A detailed review of her travel history showed a 4-month stay in Arizona as a teenager that she barely remembered. Coccidioides spp were likely misidentified as Malbranchea spp owing to similar morphological characteristics. Dosages of immunosuppressive medications were reduced, and antifungal therapy was changed to posaconazole. Her skin lesions resolved.

Management of osteoarticular fungal infections in the setting of immunodeficiency

Introduction: Osteoarticular fungal infections (OAFIs) complicate the clinical course of high-risk patients, including immunosuppressed individuals. Their management, however, despite being intricate, is governed by evidence arising from sub-optimal quality research, such as case series. Guidelines are scarce and when present result in recommendations based on low quality evidence. Furthermore, the differences between the management of immunocompromised and immunocompetent patients are not distinct. This is a narrative review after a literature search in PubMed, up to November 2019.Areas covered: The major fungal groups causing osteomyelitis and/or arthritis are Candida spp., Aspergillus spp., non-Aspergillus filamentous fungi, non-Candida yeasts and endemic dimorphic fungi. Their epidemiology is briefly analyzed with emphasis on immunodeficiency and other risk factors. Management of OAFIs includes appropriate antifungal drug therapy (liposomal amphotericin B, triazoles or echinocandins), local surgery and immunotherapy for primary immunodeficiencies. Cessation of immunosuppressive drugs is also mandated.Expert opinion: Management of OAFIs includes affordable and available options and approaches. However, research on therapeutic practices is urgently required to be further improved, due to the rarity of affected patients. Evolution is expected to translate into novel antifungal drugs, less invasive and precise surgical approaches and targeted enhancement of immunoregulatory pathways in defense of challenging fungal pathogens.

The Rise of Coccidioides: Forces Against the Dust Devil Unleashed

Coccidioidomycosis (Valley fever) is a fungal disease caused by the inhalation of Coccidioides posadasii or C. immitis. This neglected disease occurs in the desert areas of the western United States, most notably in California and Arizona, where infections continue to rise. Clinically, coccidioidomycosis ranges from asymptomatic to severe pulmonary disease and can disseminate to the brain, skin, bones, and elsewhere. New estimates suggest as many as 350,000 new cases of coccidioidomycosis occur in the United States each year. Thus, there is an urgent need for the development of a vaccine and new therapeutic drugs against Coccidioides infection. In this review, we discuss the battle against Coccidioides including the development of potential vaccines, the quest for new therapeutic drugs, and our current understanding of the protective host immune response to Coccidioides infection.

Disseminated Coccidioidomycosis to the Spine-Case Series and Review of Literature

Coccidioidomycosis is a fungal infectious disease caused by the Coccidioides species endemic to Southwestern United States. Symptomatic patients typically present as community-acquired pneumonia. Uncommonly, in about 1% of infections, hematogenous extra pulmonary systemic dissemination involving skin, musculoskeletal system, and meninges occur. Disseminated spinal infection is treated with antifungal drugs and/or surgical treatment. A retrospective review of medical records at our institution was done between January 2009 to December 2018 and we present three cases of spinal coccidioidomycosis and review the current literature. Disseminated coccidioidomycosis can lead to spondylitis that can present as discitis or a localized spinal or paraspinal abscess. Spinal coccidioidomycosis is typically managed with antifungal treatments but can include surgical treatment in the setting poor response to medical therapy, intractable pain, presence of neurological deficits due to compression, or structural spinal instability.

Endemic fungal infections in solid organ transplant recipients-Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice

These updated guidelines from the Infectious Diseases Community of Practice of the American Society of Transplantation review the diagnosis, prevention and management of blastomycosis, histoplasmosis, and coccidioidomycosis in the pre- and post-transplant period. Though each of these endemic fungal infections has unique epidemiology and clinical manifestations, they all share a predilection for primary pulmonary infection and may cause disseminated infection, particularly in immunocompromised hosts. Culture remains the gold standard for definitive diagnosis, but more rapid diagnosis may be achieved with direct visualization of organisms from clinical specimens and antigen-based enzyme immunoassay assays. Serology is of limited utility in transplant recipients. The mainstay of treatment for severe infections remains liposomal amphotericin followed by a step-down azole therapy. Cases of mild to moderate severity with no CNS involvement may be treated with azole therapy alone. The newer generation azoles provide additional treatment options, but supported currently with limited clinical efficacy data. Azole therapy in transplant recipients presents a unique challenge owing to the drug-drug interactions with immunosuppressant agents. Therapeutic drug monitoring of azole levels is an essential component of effective and safe therapy. Infection prevention centers around minimizing epidemiological exposures, early clinical recognition, and azole prophylaxis in selected individuals.

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.

Endemic Mycoses in Solid Organ Transplant Recipients

The endemic mycoses are a group of thermally dimorphic fungal pathogens occupying a specific geographic range. In North America, the chief endemic mycoses are histoplasmosis, coccidioidomycosis, and blastomycosis. Endemic fungi can cause serious infections in solid organ transplant recipients from primary infection, reactivation of latent disease, or donor-derived infection.

Pre-Existing Liver Disease and Toxicity of Antifungals

Pre-existing liver disease in patients with invasive fungal infections further complicates their management. Altered pharmacokinetics and tolerance issues of antifungal drugs are important concerns. Adjustment of the dosage of antifungal agents in these cases can be challenging given that current evidence to guide decision-making is limited. This comprehensive review aims to evaluate the existing evidence related to antifungal treatment in individuals with liver dysfunction. This article also provides suggestions for dosage adjustment of antifungal drugs in patients with varying degrees of hepatic impairment, after accounting for established or emerging pharmacokinetic–pharmacodynamic relationships with regard to antifungal drug efficacy in vivo.

Hospitalized burden and outcomes of coccidioidomycosis: A nationwide analysis, 2005-2012

The incidence of coccidioidomycosis (CM) infection has increased over the last 20 years. We investigated recent trends of CM-associated hospitalization in the United States. patients with CM-associated hospitalization were identified from the Nationwide Inpatient Sample, 2005-2012. The outcomes of interest were the trend of annual hospitalization, in-hospital mortality, and independent risk factors for mortality. A total of 30,870 hospitalizations with CM (29,584 of adults; 1,286 of children) were identified. Over the 8-year study period, the number of hospitalizations for CM fluctuated but increased overall with successively higher peaks in 2009 and 2011. The annual median length of stay (LOS) shortened from 6 to 7 days in 2005-2010 to 4 days in 2011 and 5 days in 2012. The inflation-adjusted hospital charges were highest in 2006 then trended down by 21% in 2012. The in-hospital mortality declined from the highest level in 2005 (5.2%) to a low in 2010 (1.1%), then increased modestly in 2011 (1.9%) and 2012 (1.5%). Hospitalizations were identified in 46 states, with nearly half in Arizona (49.1%), followed by California (36.8%), Texas (3.3%), and Nevada (1.6%). Logistic regression analysis in adults revealed that in-hospital mortality was associated with age groups 61-70 years and >70 years (OR = 3.3 and 3.5, respectively. Ref: 18-30 years) and Charlson Index ≥1 (OR = 2.0-8.3). In children, males had lower risk for mortality than females (OR = 0.2). This study shows that CM-associated hospitalizations occur widely throughout the United States with an increasing admission trend; however, patient outcomes have improved and the cost of hospitalization has decreased.

Spinal Coccidioidomycosis: A Current Review of Diagnosis and Management

OBJECTIVE

Coccidioidomycosis is an invasive fungal disease that may present with extrathoracic dissemination. Patients with spinal coccidioidomycosis require unique medical and surgical management. We review the risk factors and clinical presentations, discuss the indications for surgical intervention, and evaluate outcomes and complications after medical and surgical management.

METHODS

A review of the English-language literature was performed. Eighteen articles included the management of 140 patients with spinal coccidioidomycosis.

RESULTS

For the 140 patients, risk factors included male sex (95%), African American ethnicity (52%), and a recent visit to endemic areas (16%). The most frequent clinical presentation was pain (n = 80, 57%), followed by neurologic compression (52%). One-third of patients had concurrent pulmonary disease. The sensitivity of culture and histology for coccidioidomycosis was 80% and 90%, respectively. Complement fixation titers >1:128 suggest extensive or refractory vertebral infection. The most commonly affected spinal segments were the thoracic and lumbar spine (69%); an additional 40 patients (29%) had epidural and paravertebral abscesses. All patients received therapy with azoles (60%) and/or amphotericin B (43%). Surgical and medical management were used conjunctively to treat 110 patients (79%), with debridement (95% [105/110]) and fusion (64% [70/110]) being the most common surgical procedures. Clinical outcome improved/remained unchanged in 83 patients (59%) and worsened in 4 patients (3%). The mortality was 7%. Infection recurrence and disease progression were the most frequent complications.

CONCLUSIONS

Emphasis should be placed on continuous and lifelong appropriate azole therapy. Spinal instability and neurologic compromise are surgical indications for decompression and fusion.

Comparison of Plasma Concentrations of Posaconazole with the Oral Suspension and Tablet in Korean Patients with Hematologic Malignancies

The posaconazole tablet formulation was developed to have improved bioavailability compared to the oral suspension. Here, we compared posaconazole plasma concentration (PPC) with the posaconazole oral suspension versus the tablet in Korean patients undergoing remission induction chemotherapy for hematologic malignancies. PPC was measured at 3, 8, and 15 days of treatment with the oral suspension (174 patients) or the tablet (40 patients). At all time-points, mean PPC was significantly higher with the tablet compared to the oral suspension. Our findings suggest that posaconazole tablets generate an optimal PPC earlier and in more patients than the oral suspension among Korean patients.

Clinical hepatotoxicity associated with antifungal agents

INTRODUCTION

Invasive fungal diseases (IFDs) are a leading cause of morbidity and mortality among immunocompromised patients with bone marrow failure syndromes, hematological malignancies, hematopoietic stem cell transplantation (HSCT), those admitted in intensive care units (ICUs) and those with prolonged febrile neutropenia. IFDs occur in a setting of multiple morbidities and are associated with case fatality rates between 30 and 70%. Along with the development of classes and compounds, the last two decades have seen substantial improvements in the prevention and management of these infections and an overall increased use of antifungal agents. Areas covered: All antifungal agents, including amphotericin B formulations, echinocandins and the triazoles, may cause hepatic toxicity that ranges from mild and asymptomatic abnormalities in liver function tests to substantial liver injury and fulminant hepatic failure. Expert opinion: The present article reviews incidence and severity of hepatotoxicity associated with different classes and agents to provide a better understanding of this specific end organ toxicity and safer use of antifungal agents A thorough understanding of the distribution, metabolism, elimination and drug-drug interactions of antifungal agents used for management of IFDs in combination with safety data from clinical trials, pharmacokinetic and pharmacodynamic studies may guide the use of antifungal treatment in patients at high risk for the development of hepatic dysfunction and in those with underlying liver damage due to cytotoxic therapy.

2016 Infectious Diseases Society of America (IDSA) Clinical Practice Guideline for the Treatment of Coccidioidomycosis

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. Infectious Diseases Society of America 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.Coccidioidomycosis, also known as San Joaquin Valley fever, is a systemic infection endemic to parts of the southwestern United States and elsewhere in the Western Hemisphere. Residence in and recent travel to these areas are critical elements for the accurate recognition of patients who develop this infection. In this practice guideline, we have organized our recommendations to address actionable questions concerning the entire spectrum of clinical syndromes. These can range from initial pulmonary infection, which eventually resolves whether or not antifungal therapy is administered, to a variety of pulmonary and extrapulmonary complications. Additional recommendations address management of coccidioidomycosis occurring for special at-risk populations. Finally, preemptive management strategies are outlined in certain at-risk populations and after unintentional laboratory exposure.

THE TREATMENT OF COCCIDIOIDOMYCOSIS

Therapy of coccidioidomycosis continues to evolve. For primary pulmonary disease, antifungal therapy is frequently not required while prolonged courses of antifungals are generally needed for those in whom extrathoracic disseminated has occurred. Intravenous amphotericin B should be reserved for those with severe disease. Oral triazole antifungals have had a great impact on the management of coccidioidomycosis. Both fluconazole and itraconazole at 400 mg daily have been effective for various forms of coccidioidomycosis, including meningitis, although relapse after therapy is discontinued is a problem. Individuals with suppressed cellular immunity are at increased risk for symptomatic coccidioidomycosis and they include those with HIV infection, those on immunosuppressive medications, and those who have received a solid organ transplant. Pregnant women and African-American men have been identified as two other groups who are at an increased risk for symptomatic and severe infection.

Pharmacologic and clinical evaluation of posaconazole

Posaconazole, a broad-spectrum triazole antifungal agent, is approved for the prevention of invasive aspergillosis and candidiasis in addition to the treatment of oropharyngeal candidiasis. There is evidence of efficacy in the treatment and prevention of rarer, more difficult-to-treat fungal infections. Posaconazole oral suspension solution has shown limitations with respect to fasting state absorption, elevated gastrointestinal pH and increased motility. The newly approved delayed-release oral tablet and intravenous solution formulations provide an attractive treatment option by reducing interpatient variability and providing flexibility in critically ill patients. On the basis of clinical experience and further clinical studies, posaconazole was found to be a valuable pharmaceutical agent for the treatment of life-threatening fungal infections. This review will examine the development history of posaconazole and highlight the most recent advances.

A paradigm for the evaluation and management of spinal coccidioidomycosis

Background:

Coccidioidomycosis is a fungal infection that is endemic to parts of the Southwestern United States. When infection involves the spine, the treatment strategies can be challenging. We have devised a management protocol for spinal coccidioidomycosis based on a review of the literature and our experience.

Methods:

The electronic literature search of National Library of Medicine for publications from 1964 to 2014 was performed using the following keywords: Coccidioidomycosis and spine. The search yielded 24 papers. Treatment strategies were summarized into a treatment protocol.

Results:

A total of 164 cases of spinal coccidioidomycosis were identified, ranging in age from <10 to >80 years. Males (n = 131) and African-Americans (n = 79) were strikingly over-represented. Medical therapy: Once a diagnosis of spinal coccidioidomycosis is established, antifungal therapy should always be started. Antifungal therapy with amphotericin B or azoles like fluconazole. Medical therapy needs to be continued for many years and sometimes indefinitely to reduce disease recurrence or progression. Surgical management is indicated in cases with mechanical instability, neurologic deficit, medically intractable pain, or progression of infection despite antifungal therapy.

Conclusions:

This work provides a working protocol involving assessment and reassessment for the management of spinal coccidioidomycosis. Medical management with antifungal agents in some cases can provide satisfactory disease control. However, in patients with mechanical instability, neurologic deficit, medically intractable pain or disease progression disease control may only be achieved with surgical debridement and stabilization.

Antifungal clinical trials and guidelines: what we know and do not know

For over the last three decades, extensive testing of antifungal compounds in clinical trials has been essential to the development of treatment guidelines for the most common invasive fungal infections, including cryptococcosis, candidiasis, aspergillosis, and the endemic fungi. These guidelines have greatly helped guide clinicians in the management of these complicated diseases. The data on which most of these guidelines are based are among the most widely recognized and cited clinical trials comparing antimicrobial agents. Unfortunately, there are many unanswered questions with respect to the diagnosis and treatment of these emerging disorders. Regarding treatment, there is a need for more clinically effective and less toxic agents. The current armamentarium of antifungal agents represents important progress over gold standard agents such as amphotericin B, but there is much progress to be made. With respect to diagnostics, mycology has generally lagged behind other disciplines in microbiology, as there are very few rapid, sensitive, specific, and point-of-care diagnostics. The ability to implement therapies for at-risk patients based on positive early diagnostic signals would greatly enhance the ability to intervene with appropriate antifungal therapy in a more targeted and specific manner. This article will review some of the major advances, as well as significant challenges that remain in the management of invasive mycoses.

Recent advances in our understanding of the environmental, epidemiological, immunological, and clinical dimensions of coccidioidomycosis

Coccidioidomycosis is the endemic mycosis caused by the fungal pathogens Coccidioides immitis and C. posadasii. This review is a summary of the recent advances that have been made in the understanding of this pathogen, including its mycology, genetics, and niche in the environment. Updates on the epidemiology of the organism emphasize that it is a continuing, significant problem in areas of endemicity. For a variety of reasons, the number of reported coccidioidal infections has increased dramatically over the past decade. While continual improvements in the fields of organ transplantation and management of autoimmune disorders and patients with HIV have led to dilemmas with concurrent infection with coccidioidomycosis, they have also led to advances in the understanding of the human immune response to infection. There have been some advances in therapeutics with the increased use of newer azoles. Lastly, there is an overview of the ongoing search for a preventative vaccine.

Fungal infections in cancer patients

Invasive fungal infections (IFI) have become a leading cause of morbidity and mortality in cancer patients. Infections with these organisms are often difficult to diagnose and treat. Appropriate and timely diagnosis requires a high index of suspicion and invasive procedures, including biopsy, to confirm the diagnosis. Treatment may be difficult, secondary to variable susceptibility and difficulty with exact and specific characterization of the fungal pathogen. The pathogens that are seen range from yeasts to invasive molds. Fortunately newer, noninvasive diagnostic techniques are available to aid in the diagnosis and treatments have become better tolerated and more efficacious.

A reference laboratory experience of clinically achievable voriconazole, posaconazole, and itraconazole concentrations within the bloodstream and cerebral spinal fluid

Interest in antifungal therapeutic-drug monitoring has increased due to studies demonstrating associations between concentrations and outcomes. We reviewed the antifungal drug concentration database at our institution to gain a better understanding of achievable triazole drug levels. Antifungal concentrations were measured by high-performance liquid chromatography (HPLC), ultraperformance liquid chromatography and single-quadrupole mass spectrometry (UPLC/MS), or a bioassay. For this study, only confirmed human bloodstream (serum or plasma) and cerebral spinal fluid (CSF) concentrations of voriconazole, posaconazole, and itraconazole were analyzed. The largest numbers of bloodstream and CSF samples were found for voriconazole (14,370 and 173, respectively). Voriconazole bloodstream concentrations within the range of 1 to 5.5 μg/ml represented 50.6% of samples. Levels below the lower limit of quantification (0.2 μg/ml) were observed in 14.6% of samples, and 10.4% of samples had levels of ≥5.5 μg/ml. CSF voriconazole levels ranged from undetectable to 15.3 μg/ml and were <0.2 μg/ml in 11% of samples. Posaconazole bloodstream concentrations were ≥0.7 and ≥1.25 μg/ml in 41.6% and 18.9% of samples, respectively. Posaconazole was detected in only 4 of 22 CSF samples (undetectable to 0.56 μg/ml). Itraconazole levels, as measured by UPLC/MS, were ≥0.5 μg/ml in 43.3% and were undetectable in 33.9% of bloodstream samples. In contrast, when measured by a bioassay, itraconazole/hydroxyitraconazole bloodstream concentrations were ≥1.0 μg/ml in 72.9% of samples and were undetectable in 18% of samples. These results indicate that there is marked variability in bloodstream concentrations achieved with these three azoles. In addition, many levels within the bloodstream for each azole and for voriconazole and posaconazole in the CSF were undetectable or below thresholds associated with efficacy.

Posaconazole exposure-response relationship: evaluating the utility of therapeutic drug monitoring

Posaconazole has become an important part of the antifungal armamentarium in the prophylaxis and salvage treatment of invasive fungal infections (IFIs). Structurally related to itraconazole, posaconazole displays low oral bioavailability due to poor solubility, with significant drug interactions and gastrointestinal disease also contributing to the generally low posaconazole plasma concentrations observed in patients. While therapeutic drug monitoring (TDM) of plasma concentrations is widely accepted for other triazole antifungal agents such as voriconazole, the utility of TDM for posaconazole is controversial due to debate over the relationship between posaconazole exposure in plasma and clinical response to therapy. This review examines the available evidence for a relationship between plasma concentration and clinical efficacy for posaconazole, as well as evaluating the utility of TDM and providing provisional target concentrations for posaconazole therapy. Increasing evidence supports an exposure-response relationship for plasma posaconazole concentrations for prophylaxis and treatment of IFIs; a clear relationship has not been identified between posaconazole concentration and toxicity. Intracellular and intrapulmonary concentrations have been studied for posaconazole but have not been correlated to clinical outcomes. In view of the high mortality and cost associated with the treatment of IFIs, increasing evidence of an exposure-response relationship for posaconazole efficacy in the prevention and treatment of IFIs, and the common finding of low posaconazole concentrations in patients, TDM for posaconazole is likely to be of significant clinical utility. In patients with subtherapeutic posaconazole concentrations, increased dose frequency, administration with high-fat meals, and withdrawal of interacting medications from therapy are useful strategies to improve systemic absorption.

Vertebral coccidioidomycosis: presentation and multidisciplinary management

BACKGROUND

Vertebral involvement is a severe complication of infection caused by Coccidioides species.

METHODS

We conducted a retrospective review of patients diagnosed with vertebral coccidioidomycosis at an academic medical center between 1996 and 2009.

RESULTS

We identified 39 cases of vertebral coccidioidomycosis. Thirty-four patients (79%) were male, and 23 patients (61%) were black. Black patients were overrepresented in comparison with all other patients by a 50-fold odds ratio (95% confidence interval, 26-95). Only 8 patients (20%) were immunocompromised, including 7 who had received systemic steroids. The number of infected vertebrae ranged from 1 to 24; 8 patients (21%) had epidural involvement. All patients received a triazole as part of medical therapy, and 20 patients also received amphotericin B, typically early in the course. Twenty-six patients (67%) required surgery, 18 of whom also required hardware placement. The most common indication for surgery was pain, but 7 patients had neurologic compromise. No patients developed recurrent or refractory infection at the site of surgical debridement, but 6 patients experienced disease relapse after stopping antifungal therapy.

CONCLUSION

Vertebral infection caused by Coccidioides species requires a multispecialty approach that always includes medical therapy and frequently requires surgical intervention for debridement or stabilization. A favorable outcome can usually be achieved, but discontinuation of medical therapy is associated with a high risk of relapse, which can occur years later.

Posaconazole: A new agent for the prevention and management of severe, refractory or invasive fungal infections

Posaconazole is the newest antifungal agent to be approved for use in Canada. With excellent in vitro activity against a broad spectrum of yeasts and filamentous fungi, as well as having a well-tolerated oral formulation, posaconazole offers many potential advantages. Of particular interest are its seemingly lower potential for cross-resistance with other azoles and its activity (unique among oral antifungal agents) against the zygomycetes. As the incidence of both common and uncommon fungal infections increases commensurate with the growing population of immunocompromised individuals, posaconazole may ultimately become an important therapeutic option. The present article reviews the in vitro and in vivo data describing its activity, and focuses on both the proven and the potential clinical applications of this new triazole agent.

Posaconazole in the management of refractory invasive fungal infections

The rising incidence of invasive fungal infections due to the expanding population of immunocompromised hosts and the increasing prevalence of fungal resistance has led to the need for novel antifungal agents. Posaconazole, a new member of the triazole class has demonstrated in vitro activity against a broad spectrum of fungi and clinical activity against various fungal pathogens, including Aspergillus spp., Candida spp., zygomycetes, and Fusarium spp. To date, posaconazole has been approved for prophylaxis of invasive fungal infections in stem cell transplant recipients with acute graft versus host disease (GVHD) and neutropenic patients receiving intensive induction chemotherapy for acute myelogenous leukemia and myelodys-plastic syndrome. In addition, it has been licensed for use in oropharyngeal candidiasis and for salvage therapy in invasive aspergillosis, fusariosis, coccidioidomycosis, chromoblastomycosis, and mycetoma. Posaconazole is the only azole with activity against zygomycetes and other difficult-to-treat fungi, representing a potential treatment option for refractory invasive mycosis. This article reviews available preclinical and clinical data of posaconazole, focusing on its role in the teatment of refractory invasive fungal infections.