Improving awareness, diagnosis and management of invasive fungal infections in Ghana: establishment of the Ghana Medical Mycology Society.

Invasive fungal infections (IFIs) and medical mycology receive little attention in Ghana. However, the present evolution of biomarker assays for IFIs, offers an opportunity for an increased access to fungal laboratory testing in resource-limited settings, and probably make a case for availability of essential antifungal agents. Using surveys and personal communications, the state of medical mycology and IFI in Ghana were highlighted. Inadequate awareness and insufficient access to fungal diagnostics and therapeutics were identified as the key challenges, the establishment of the Ghana Medical Mycology Society was discussed, and recommendations were made to improve the status quo.

Invasive fungal infections (IFIs) receive little attention in Ghana, despite its growing relevance globally. Using surveys and personal communications, the main challenges were identified, and the formation of the Ghana Medical Mycology Society was discussed as a tool to improve the status quo.

Talaromycosis in a renal transplant recipient returning from South China.

Talaromycosis is a fungal infection endemic in Southeast Asia. We report a case of a renal transplant recipient who developed infection after a trip to South China. She presented with constitutional symptoms and was found to have an FDG-avid lung mass. Histopathology demonstrated small yeast cells and culture grew Talaromyces marneffei. The patient was treated with 2 weeks of liposomal amphotericin B followed by itraconazole. The dose of tacrolimus was significantly reduced because of the interaction with itraconazole. Mycophenolate mofetil was discontinued. After 12 months of treatment, the mass had completely resolved. Talaromycosis has mainly been reported in patients with AIDS and is uncommon among solid organ transplant recipients. The immune response against T. marneffei infection is mediated predominantly by T cells and macrophages. The diagnosis may not be suspected outside of endemic areas. We propose a therapeutic approach in transplant patients by extrapolating the evidence from the HIV literature and following practices applied to other endemic mycoses.

Pulmonary Aspergillosis in Patients with Suspected Ventilator-associated Pneumonia in UK ICUs.

Rationale:Aspergillus infection in patients with suspected ventilator-associated pneumonia remains uncharacterized because of the absence of a disease definition and limited access to sensitive diagnostic tests.Objectives: To estimate the prevalence and outcomes of Aspergillus infection in adults with suspected ventilator-associated pneumonia.Methods: Two prospective UK studies recruited 360 critically ill adults with new or worsening alveolar shadowing on chest X-ray and clinical/hematological parameters supporting suspected ventilator-associated pneumonia. Stored serum and BAL fluid were available from 194 nonneutropenic patients and underwent mycological testing. Patients were categorized as having probable Aspergillus infection using a definition comprising clinical, radiological, and mycological criteria. Mycological criteria included positive histology or microscopy, positive BAL fluid culture, galactomannan optical index of 1 or more in BAL fluid or 0.5 or more in serum.Measurements and Main Results: Of 194 patients evaluated, 24 met the definition of probable Aspergillus infection, giving an estimated prevalence of 12.4% (95% confidence interval, 8.1-17.8). All 24 patients had positive galactomannan in serum (n = 4), BAL fluid (n = 16), or both (n = 4); three patients cultured Aspergillus sp. in BAL fluid. Patients with probable Aspergillus infection had a significantly longer median duration of critical care stay (25.5 vs. 15.5 d, P = 0.02). ICU mortality was numerically higher in this group, although this was not statistically significant (33.3% vs. 22.8%; P = 0.23).Conclusions: The estimated prevalence for probable Aspergillus infection in this geographically dispersed multicenter UK cohort indicates that this condition should be considered when investigating patients with suspected ventilator-associated pneumonia, including patient groups not previously recognized to be at high risk of aspergillosis.

Isavuconazole Therapeutic Drug Monitoring during Long-Term Treatment for Chronic Pulmonary Aspergillosis.

Isavuconazole is the newest triazole antifungal, and it displays a favorable pharmacokinetic and safety profile. Less is known about its long-term use in immunocompetent hosts. We performed a retrospective service evaluation of isavuconazole therapeutic drug monitoring in patients with chronic pulmonary aspergillosis. Adverse events (AEs) and dose adjustments made during routine clinical practice were recorded, and AEs were classified based on Common Terminology Criteria for Adverse Events v5.0. Forty-five patients (mean age, 64 years) had 285 isavuconazole blood drug levels measured (mean level, 4.1 mg/liter). A total of 117 measurements (41%) were performed on patients on a 100-mg daily dose instead of 200 mg, and all had blood levels of >1 mg/liter. Age (P = 0.012) and a daily dose of 200 mg versus 100 mg (P = 0.02) were independent predictors of levels of >6 mg/liter. AEs were recorded for 25 patients (56%). The mean drug level at the first measurement was 5.5 ± 2 mg/liter for patients reporting AEs, compared with 4.2 ± 1.7 mg/liter for those not reporting AEs (P = 0.032). The cutoff threshold best predictive of an AE was 4.6 mg/liter (area under the concentration-time curve, 0.710). Sixteen patients (36%) discontinued isavuconazole therapy due to AEs. Twenty-six patients (58%) continued on isavuconazole beyond 6 months. Asthma (P = 0.022) and a daily dose of 200 mg versus 100 mg (P = 0.048) were associated with AEs of grade 2 or higher. A reduced daily dose (100 mg versus 200 mg) of isavuconazole resulted in satisfactory drug levels in a substantial number of patients; it was better tolerated and enabled continuation of therapy for prolonged periods.

Deciphering Aspergillus fumigatus cyp51A-mediated triazole resistance by pyrosequencing of respiratory specimens.

BACKGROUND: Infections caused by triazole drug-resistant Aspergillus fumigatus are an increasing problem. The sensitivity of standard culture is poor, abrogating susceptibility testing. Early detection of resistance can improve patient outcomes, yet tools for this purpose are limited. OBJECTIVES: To develop and validate a pyrosequencing technique to detect resistance-conferring cyp51A polymorphisms from clinical respiratory specimens and A. fumigatus isolates. METHODS: Method validation was performed by Sanger sequencing and pyrosequencing of 50 A. fumigatus isolates with a spectrum of triazole susceptibility patterns. Then, 326 Aspergillus quantitative PCR (qPCR)-positive respiratory samples collected over a 27 month period (January 2017-March 2019) from 160 patients at the UK National Aspergillosis Centre were assessed by cyp51A pyrosequencing. The Sanger sequencing and pyrosequencing results were compared with those from high-volume culture and standard susceptibility testing. RESULTS: The cyp51A genotypes of the 50 isolates analysed by pyrosequencing and Sanger sequencing matched. Of the 326 Aspergillus qPCR-positive respiratory specimens, 71.2% were reported with no A. fumigatus growth. Of these, 56.9% (132/232) demonstrated a WT cyp51A genotype and 31.5% (73/232) a resistant genotype by pyrosequencing. Pyrosequencing identified the environmental TR34/L98H mutation in 18.7% (61/326) of the samples in contrast to 6.4% (21/326) pan-azole resistance detected by culture. Importantly, pyrosequencing detected resistance earlier than culture in 23.3% of specimens. CONCLUSIONS: The pyrosequencing assay described could detect a wide range of cyp51A polymorphisms associated with triazole resistance, including those not identified by commercial assays. This method allowed prompt recognition of resistance and the selection of appropriate antifungal treatment when culture was negative.

Positive Aspergillus PCR as a marker of azole resistance or sub-therapeutic antifungal therapy in patients with chronic pulmonary aspergillosis.

BACKGROUND: Chronic pulmonary aspergillosis (CPA) is a progressive respiratory disease, caused most commonly by A fumigatus, with significant morbidity and mortality. Azole resistance in A fumigatus is a growing concern worldwide, with resistance to itraconazole reported in up to 50% of patients. AIM: The aim of this study was to determine whether a positive Aspergillus PCR (polymerase chain reaction) is a marker of resistance in CPA patients on azole therapy. METHODS: Patients were selected via a consecutive database search for the first 50 CPA patients with a positive Aspergillus PCR from January to September 2016. Data were collected regarding concurrent and subsequent culture results, current therapy and serum antifungal levels. PCR-positive patients not on therapy were included as the control group. RESULTS: Twenty-three patients were on therapy (15 itraconazole, 4 voriconazole and 4 posaconazole). Cycle threshold (Ct) values ranged from 20.8 to 37.9; no significant difference was found between each treatment and the control group (P = .47). In treated patients, concurrent azole-resistant A fumigatus was found in 75% of A fumigatus-positive cultures (6/8). All of the resistant isolates in the itraconazole group showed therapy resistance. Twenty per cent of all itraconazole levels were sub-therapeutic. No significant difference was found in serum itraconazole levels for patients on itraconazole with a positive PCR versus negative PCR (P = .44). CONCLUSION: Positive sputum, Aspergillus-specific PCR can be associated with azole resistance in CPA patients on therapy.

Evaluation of LDBio Aspergillus ICT Lateral Flow Assay for IgG and IgM Antibody Detection in Chronic Pulmonary Aspergillosis.

Detecting Aspergillus-specific IgG is critical to diagnosing chronic pulmonary aspergillosis (CPA). Existing assays are often cost- and resource-intensive and not compatible with resource-constrained laboratory settings. LDBio Diagnostics has recently commercialized a lateral flow assay based on immunochromatographic technology (ICT) that detects Aspergillus antibodies (IgG and IgM) in less than 30 min, requiring minimal laboratory equipment. A total of 154 CPA patient sera collected at the National Aspergillosis Centre (Manchester, United Kingdom) and control patient sera from the Peninsula Research Bank (Exeter, United Kingdom) were evaluated. Samples were applied to the LDBio Aspergillus ICT lateral flow assay, and results were read both visually and digitally. Results were compared with Aspergillus IgG titers in CPA patients, measured by ImmunoCAP-specific IgG assays. For proven CPA patients versus controls, sensitivity and specificity for the LDBio Aspergillus ICT were 91.6% and 98.0%, respectively. In contrast, the routinely used ImmunoCAP assay exhibited 80.5% sensitivity for the same cohort (cutoff value, 40 mg of antigen-specific antibodies [mgA]/liter). The assay is easy to perform but challenging to read when only a very faint band is present (5/154 samples tested). The ImmunoCAP Aspergillus IgG titer was also compared with the Aspergillus ICT test line intensity or rate of development, with weak to moderate correlations. The Aspergillus ICT lateral flow assay exhibits excellent sensitivity for serological diagnosis of CPA. Quantifying IgG from test line intensity measurements is not reliable. Given the short run time, simplicity, and limited resources needed, the LDBio Aspergillus ICT is a suitable diagnostic tool for CPA in resource-constrained settings.

An introduction to current standards of CARE in invasive fungal disease.

Invasive fungal infections are life-threatening conditions that require rapid diagnosis and optimal management to alleviate their high morbidity and mortality. They are also associated with a high economic burden, owing to prolonged hospitalization, the need for intensive supportive care, and the consumption of costly new antifungal agents. Many standards of care and guidelines have been published by national and international medical societies and organizations over the past 20 years that have embraced new diagnostic technologies and strategies, and new antifungal drugs. Recognizing the ongoing need and debate on the topic of standards for optimal diagnostics and patient care, the Scientific Committee of the Continuing Antifungal Research and Education (CARE) programme devised the scientific agenda for the 10th CARE (CARE X) meeting to review current practice and recommendations. Specialists in haematology, infectious diseases, medical microbiology and medical mycology met in Barcelona in November 2017. The meeting was organized and funded by Gilead Sciences Europe Ltd.

Diagnosis and treatment of invasive fungal infections: looking ahead.

Improved standards of care depend on the development of new laboratory diagnostic and imaging procedures and the development of new antifungal compounds. Immunochromatography technologies have led to the development of lateral flow devices for the diagnosis of cryptococcal meningitis and invasive aspergillosis (IA). Similar devices are being developed for the detection of histoplasmosis that meet the requirements for speed (∼15 min assay time) and ease of use for point-of-care diagnostics. The evolution of molecular tools for the detection of fungal pathogens has been slow but the introduction of new nucleic acid amplification techniques appears to be helpful, for example T2Candida. An Aspergillus proximity ligation assay has been developed for a rapid near-patient bedside diagnosis of IA. CT remains the cornerstone for radiological diagnosis of invasive pulmonary fungal infections. MRI of the lungs may be performed to avoid radiation exposure. MRI with T2-weighted turbo-spin-echo sequences exhibits sensitivity and specificity approaching that of CT for the diagnosis of invasive pulmonary aspergillosis. The final part of this review looks at new approaches to drug discovery that have yielded new classes with novel mechanisms of action. There are currently two new classes of antifungal drugs in Phase 2 study for systemic invasive fungal disease and one in Phase 1. These new antifungal drugs show promise in meeting unmet needs with oral and intravenous formulations available and some with decreased potential for drug-drug interactions. Novel mechanisms of action mean these agents are not susceptible to the common resistance mechanisms seen in Candida or Aspergillus. Modification of existing antifungal susceptibility testing techniques may be required to incorporate these new compounds.

Therapeutic drug monitoring and adverse events of delayed-release posaconazole tablets in patients with chronic pulmonary aspergillosis.

BACKGROUND: Posaconazole delayed-release tablets offer better bioavailability than the liquid suspension, but no post-marketing data are available in immunocompetent hosts such as those with chronic pulmonary aspergillosis (CPA). OBJECTIVES: To explore the pharmacokinetics and adverse event (AE) profile of posaconazole tablets in patients with CPA. METHODS: Patients started on posaconazole tablets at the National Aspergillosis Centre (NAC), Manchester, UK between February 2014 and October 2015 were identified from the NAC database and analysed retrospectively. The medical records were reviewed for factors that could affect posaconazole serum levels and the development of AEs. RESULTS: Seventy-two patients were included; 50 (69%) were male and the mean age was 48.5 ±âŸ12 years. Therapeutic levels (≥1 mg/L) were achieved in 90% of cases on 200 mg versus 90% of cases on 300 mg daily (P = not significant). Based on multivariate analysis, female sex (P = 0.041), a 100 mg daily dose (P < 0.001), asthma (P = 0.01) and bronchiectasis (P = 0.001) were associated with subtherapeutic levels. Forty-nine (68%) patients developed AEs, mainly fatigue (37%), dyspnoea (18%) and nausea (12%). AEs were present on 115/196 (59%) occasions on 300 mg/day and on 45/115 (39%) occasions on 200 mg/day (P < 0.01). The mean level was 1.81 ±âŸ0.96 mg/L for patients reporting no AEs and 1.90 ±âŸ1.11 mg/L for those reporting AEs (P = not significant). Factors associated with AEs of grade ≥2 were a daily dose of 300 versus 200 mg (P = 0.001) and asthma (P = 0.008). CONCLUSIONS: A lower-than-recommended posaconazole tablet dose achieved therapeutic levels in most patients and was better tolerated. Males were more likely to achieve a therapeutic level. Underlying conditions affected the degree and frequency of AEs.

Siemens Immulite Aspergillus-specific IgG assay for chronic pulmonary aspergillosis diagnosis.

Chronic pulmonary aspergillosis (CPA) complicates underlying lung disease, including treated tuberculosis. Measurement of Aspergillus-specific immunoglobulin G (IgG) is a key diagnostic step. Cutoffs have been proposed based on receiver operating characteristic (ROC) curve analyses comparing CPA cases to healthy controls, but performance in at-risk populations with underlying lung disease is unclear. We evaluated optimal cutoffs for the Siemens Immulite Aspergillus-specific IgG assay for CPA diagnosis in relation to large groups of healthy and diseased controls with treated pulmonary tuberculosis. Sera from 241 patients with CPA attending the UK National Aspergillosis Centre, 299 Ugandan blood donors (healthy controls), and 398 Ugandans with treated pulmonary tuberculosis (diseased controls) were tested. Radiological screening removed potential CPA cases from diseased controls (234 screened diseased controls). ROC curve analyses were performed and optimal cutoffs identified by Youden J statistic. CPA versus control ROC area under curve (AUC) results were: healthy controls 0.984 (95% confidence interval 0.972-0.997), diseased controls 0.972 (0.959-0.985), screened diseased controls 0.979 (0.967-0.992). Optimal cutoffs were: healthy controls 15 mg/l (94.6% sensitivity, 98% specificity), unscreened diseased controls 15 mg/l (94.6% sensitivity, 94.5% specificity), screened diseased controls 25 mg/l (92.9% sensitivity, 98.7% specificity). Results were similar in healthy and diseased controls. We advocate a cutoff of 20 mg/l as this is the midpoint of the range of optimal cutoffs. Cutoffs calculated in relation to healthy controls for other assays are likely to remain valid for use in a treated tuberculosis population.

Case Definition of Chronic Pulmonary Aspergillosis in Resource-Constrained Settings.

Chronic pulmonary aspergillosis (CPA) is a recognized complication of pulmonary tuberculosis (TB). In 2015, the World Health Organization reported 2.2 million new cases of nonbacteriologically confirmed pulmonary TB; some of these patients probably had undiagnosed CPA. In October 2016, the Global Action Fund for Fungal Infections convened an international expert panel to develop a case definition of CPA for resource-constrained settings. This panel defined CPA as illness for >3 months and all of the following: 1) weight loss, persistent cough, and/or hemoptysis; 2) chest images showing progressive cavitary infiltrates and/or a fungal ball and/or pericavitary fibrosis or infiltrates or pleural thickening; and 3) a positive Aspergillus IgG assay result or other evidence of Aspergillus infection. The proposed definition will facilitate advancements in research, practice, and policy in lower- and middle-income countries as well as in resource-constrained settings.

A systematic review of fluconazole resistance in clinical isolates of Cryptococcus species.

Fluconazole is the most commonly used antifungal agent for both the treatment of cryptococcal meningitis, and for prophylaxis against the disease. However, its prolonged use has the potential to exert selection pressure in favour of fluconazole-resistant strains. We evaluated the prevalence of fluconazole resistance in Cryptococcus spp. clinical isolates in 29 studies from 1988 to May 2017 included in EMBASE and MEDLINE databases. A total of 4995 Cryptococcus isolates from 3210 patients constituted this study; 248 (5.0%) of the isolates from relapsed episodes of cryptococcosis were included in this analysis. Eleven (38%) of the studies used minimum inhibitory concentrations (MICs) breakpoints of ≥64 µg/mL to define fluconazole resistance, 6 (21%) used ≥32 µg/mL, 11 (38%) used ≥16 µg/mL and 1 (3%) used ≤20 µg/mL. Overall, mean prevalence of fluconazole resistance was 12.1% (95% confidence interval [CI]: 6.7-17.6) for all isolates (n = 4995). Mean fluconazole resistance was 10.6% (95% CI: 5.5-15.6) for the incident isolates (n = 4747) and 24.1% (95% CI: -3.1-51.2) for the relapse isolates (n = 248). Of the 4995 isolates, 936 (18.7%) had MICs above the ecological cut-off value. Fluconazole resistance appears to be an issue in Cryptococcus isolates from patients with relapses. It remains unclear whether relapses occur due to resistance or other factors. There is an urgent need to establish antifungal breakpoints for Cryptococcus spp.

A Review of Onychomycosis Due to Aspergillus Species.

Aspergillus spp. are emerging causative agents of non-dermatophyte mould onychomycosis (NDMO). New Aspergillus spp. have recently been described to cause nail infections. The following criteria are required to diagnose onychomycosis due to Aspergillus spp.: (1) positive direct microscopy and (2) repeated culture or molecular detection of Aspergillus spp., provided no dermatophyte was isolated. A review of 42 epidemiological studies showed that onychomycosis due to Aspergillus spp. varies between < 1 and 35% of all cases of onychomycosis in the general population and higher among diabetic populations accounting for up to 71% and the elderly; it is very uncommon among children and adolescence. Aspergillus spp. constitutes 7.7-100% of the proportion of NDMO. The toenails are involved 25 times more frequently than fingernails. A. flavus, A. terreus and A. niger are the most common aetiologic species; other rare and emerging species described include A. tubingensis, A. sydowii, A. alliaceus, A. candidus, A. versicolor, A. unguis, A. persii, A. sclerotiorum, A. uvarum, A. melleus, A. tamarii and A. nomius. The clinical presentation of onychomycosis due to Aspergillus spp. is non-specific but commonly distal-lateral pattern of onychomycosis. A negative culture with a positive KOH may point to a NDM including Aspergillus spp., as the causative agent of onychomycosis. Treatment consists of systemic therapy with terbinafine or itraconazole.

Biofilm-Forming Capability of Highly Virulent, Multidrug-Resistant Candida auris.

The emerging multidrug-resistant yeast pathogen Candida auris has attracted considerable attention as a source of healthcare-associated infections. We report that this highly virulent yeast has the capacity to form antifungal resistant biofilms sensitive to the disinfectant chlorhexidine in vitro.

Delivering on Antimicrobial Resistance Agenda Not Possible without Improving Fungal Diagnostic Capabilities.

Antimicrobial resistance, a major public health concern, largely arises from excess use of antibiotic and antifungal drugs. Lack of routine diagnostic testing for fungal diseases exacerbates the problem of antimicrobial drug empiricism, both antibiotic and antifungal. In support of this contention, we cite 4 common clinical situations that illustrate this problem: 1) inaccurate diagnosis of fungal sepsis in hospitals and intensive care units, resulting in inappropriate use of broad-spectrum antibacterial drugs in patients with invasive candidiasis; 2) failure to diagnose chronic pulmonary aspergillosis in patients with smear-negative pulmonary tuberculosis; 3) misdiagnosis of fungal asthma, resulting in unnecessary treatment with antibacterial drugs instead of antifungal drugs and missed diagnoses of life-threatening invasive aspergillosis in patients with chronic obstructive pulmonary disease; and 4) overtreatment and undertreatment of Pneumocystis pneumonia in HIV-positive patients. All communities should have access to nonculture fungal diagnostics, which can substantially benefit clinical outcome, antimicrobial stewardship, and control of antimicrobial resistance.

Aspergillus serology: Have we arrived yet?

Aspergillosis presents in various clinical forms, among them chronic pulmonary aspergillosis, which is a spectrum of disease entities including aspergilloma, chronic cavitary pulmonary aspergillosis, and chronic fibrosing pulmonary aspergillosis. Aspergillus also contributes to fungal allergy and sensitization. Analysis of the immune response to Aspergillus and its antigens is an integral part of the diagnosis of these diseases. Over the past half century, the techniques used to determine antibody titers have evolved from testing for precipitating and agglutinating antibodies by agar gel double diffusion and immunolectrophoresis to enzyme-linked immunosorbent assays using recombinant proteins as capture antigens. A resurgence of interest in the detection of immunoglobulins, primarily Aspergillus-specific IgG, has hinted at the possibility of distinguishing between colonization and invasion in immunocompromised patients with invasive aspergillosis. Even though there appears to be a greater degree of discrimination between the clinical forms of aspergillosis there is still a long way to travel. This review presents illustrative examples of where new diagnostic platforms and technologies have been applied to this intriguing spectrum of diseases.

A CONSORT analysis of randomised controlled trials for the treatment of invasive aspergillosis.

There is no assessment of the reporting quality of antifungal randomized, controlled trials (RCT), upon which guidelines for the treatment of invasive aspergillosis (IA) in patients with hematological malignancy are based. Trial reports were identified through Trip, Cochrane, Medline, and Embase database searches. Report quality was assessed using the 25-item CONSORT checklist and a rating scale of 1 (strongly disagree) to 4 (strongly agree). The primary endpoint was quality as assessed by mean group-scores among papers published at the time of the most recent IA treatment guidelines. Seven RCTs were identified for analysis. Overall mean group-score for all seven papers was 2.44 (out of a total of four). There were significant differences between publications regarding overall reporting quality (P < .001) and specifically for the Methods and Results (P = .004 and P = .010, respectively), which best reflect data quality. The Cornely trial report achieved the highest mean group-score overall (3.15 ± 0.93; 95% CI, 2.82, 3.47), as well as for Methods (3.36) and Results (3.40). Mean group scores also showed that it was of significantly higher overall quality than the other six publications (P-value range; .012 to <.001), and of higher quality for Methods than five publications (P-value range; .013 to <.001). Incorporating this CONSORT analysis into the evidence-based grading systems in North American (IDSA), European (ECIL and ESCMID) IA guidelines could alter the value placed on these RCTs, thereby impacting on clinical recommendations.

Therapeutic drug monitoring (TDM) of antifungal agents: guidelines from the British Society for Medical Mycology.

The burden of human disease related to medically important fungal pathogens is substantial. An improved understanding of antifungal pharmacology and antifungal pharmacokinetics-pharmacodynamics has resulted in therapeutic drug monitoring (TDM) becoming a valuable adjunct to the routine administration of some antifungal agents. TDM may increase the probability of a successful outcome, prevent drug-related toxicity and potentially prevent the emergence of antifungal drug resistance. Much of the evidence that supports TDM is circumstantial. This document reviews the available literature and provides a series of recommendations for TDM of antifungal agents.