Oral versus intravenous therapy in the treatment of systemic mycosis

OUP accepted manuscript

Background

Recent literature has demonstrated that partial oral antibiotic treatment of infectious endocarditis is non-inferior to IV therapy in select patients. Despite the rising incidence of injection drug use-related endocarditis, partial oral therapy has not been well studied in persons who inject drugs.

Objectives

To evaluate the rate of relapsed infection and 90 day mortality in patients with infectious endocarditis treated with partial oral antibiotic therapy.

Methods

Consecutive patients with infectious endocarditis treated with partial oral antibiotic therapy were identified by study investigators and reviewed by independent clinicians. The decision to use partial oral antibiotic therapy was made by the institution’s multidisciplinary endocarditis team.

Results

In 11 cases of infective endocarditis treated with partial oral antibiotic therapy, 9 of which were complicated by injection drug use, there were no relapsed infections with the primary organism. Five patients underwent surgical valve replacement, and the median duration of oral antibiotic therapy was 23 days. All patients survived to in-hospital discharge and 90 days post-discharge. Ten patients followed up with an infectious diseases provider after discharge.

Conclusions

These data add to existing literature demonstrating non-inferior outcomes with partial oral antibiotic treatment when compared with IV antibiotic treatment alone in patients with endocarditis, including persons who inject drugs.

Preliminary Characterization of NP339, a Novel Polyarginine Peptide with Broad Antifungal Activity

Fungi cause disease in nearly one billion individuals worldwide. Only three classes of antifungal agents are currently available in mainstream clinical use. Emerging and drug-resistant fungi, toxicity, and drug-drug interactions compromise their efficacy and applicability. Consequently, new and improved antifungal therapies are urgently needed. In response to that need, we have developed NP339, a 2-kDa polyarginine peptide that is active against pathogenic fungi from the genera Candida, Aspergillus, and Cryptococcus, as well as others. NP339 was designed based on endogenous cationic human defense peptides, which are constituents of the cornerstone of immune defense against pathogenic microbes. NP339 specifically targets the fungal cell membrane through a charge-charge-initiated membrane interaction and therefore possesses a differentiated safety and toxicity profile to existing antifungal classes. NP339 is rapidly fungicidal and does not elicit resistance in target fungi upon extensive passaging in vitro. Preliminary analyses in murine models indicate scope for therapeutic application of NP339 against a range of systemic and mucocutaneous fungal infections. Collectively, these data indicate that NP339 can be developed into a highly differentiated, first-in-class antifungal candidate for poorly served invasive and other serious fungal diseases.

A Critical Review on Emerging Trends in Dry Powder Inhaler Formulation for the Treatment of Pulmonary Aspergillosis

Pulmonary aspergillosis (PA), a pulmonary fungal infection caused by Aspergillus spp., is a concern for immunocompromised populations. Despite substantial research efforts, conventional treatments of PA using antifungal agents are associated with limitations such as excessive systemic exposure, serious side effects and limited availability of the therapeutics in the lungs for an adequate duration. To overcome the limitations associated with the conventional regimens, pulmonary delivery of antifungal agents has become a focal point of research because of the superiority of local and targeted drug delivery. Dry powder inhalers and nebulized formulations of antifungal agents have been developed and evaluated for their capability to effectively deliver antifungal agents to the lungs. Moreover, progress in nanotechnology and the utilization of nanocarriers in the development of pulmonary delivery formulations has allowed further augmentation of treatment capability and efficiency. Thus, the following review provides an insight into the advantages and therapeutic potential of the utilization of nanocarriers in pulmonary delivery of antifungal agents for the treatment of PA. In addition, discussions on formulation aspects and safety concerns together with the clinical and regulatory aspects of the formulations are presented, which suggest the possibility and desirability of utilization of nanocarriers in the treatment of PA.

Infektionen

In diesem Kapitel werden zunächst die für die Neurointensivmedizin wesentlichen bakteriellen Infektionen (Meningitis, spinale und Hirnabszesse, Spondylodiszitis, septisch-embolische Herdenzephalitis) abgehandelt, die trotz gezielt eingesetzter Antibiotika und neurochirurgischer Therapieoptionen noch mit einer erheblichen Morbidität und Mortalität behaftet sind. Besonderheiten wie neurovaskuläre Komplikationen, die Tuberkulose des Nervensystems, Neuroborreliose, Neurosyphilis und opportunistische Infektionen bei Immunsuppressionszuständen finden hierbei besondere Berücksichtigung. Der zweite Teil dieses Kapitels behandelt akute und chronische Virusinfektionen des ZNS sowie in einem gesonderten Abschnitt die HIVInfektion und HIV-assoziierte Krankheitsbilder sowie Parasitosen und Pilzinfektionen, die in Industrieländern seit Einführung der HAART bei HIV zwar eher seltener, aber mit zunehmender Globalisierung auch in unseren Breiten immer noch anzutreffen sind.

Mycobacterium tuberculosis cytochrome P450 enzymes: a cohort of novel TB drug targets

TB (tuberculosis) disease remains responsible for the death of over 1.5 million people each year. The alarming emergence of drug-resistant TB has sparked a critical need for new front-line TB drugs with a novel mode of action. In the present paper, we review recent genomic and biochemical evidence implicating Mycobacterium tuberculosis CYP (cytochrome P450) enzymes as exciting potential targets for new classes of anti-tuberculars. We also discuss HTS (high-throughput screening) and fragment-based drug-discovery campaigns that are being used to probe their potential druggability.

Monitoring trough voriconazole plasma concentrations in haematological patients: real life multicentre experience

The objective of this retrospective study was to evaluate results from voriconazole therapeutic drug monitoring (TDM) in haematological patients in routine clinical practice. Between 2005 and 2010, 1228 blood samples were obtained from 264 haematological patients (median 3 samples/patient; range 1-27) receiving voriconazole for targeted/preemptive treatment of invasive aspergillosis (IA) (46.3% of samples), empirical therapy (12.9%) or prophylaxis (40.8%). A high-pressure liquid chromatography assay was used to analyse voriconazole concentrations. Clinical and laboratory data were analysed retrospectively. The median of the detected voriconazole plasma concentration was 1.00 μg ml(-1) (range <0.20-13.47 μg ml(-1)). Significant inter- and intra-patients variability of measured concentrations (81.9% and 50.5%) were identified. With the exception of omeprazole administration, there was no relevant relationship between measured voriconazole concentrations and drug dose, route administration, age, gender, CYP2C19*2 genotype, gastrointestinal tract abnormality, administration via nasogastric tube, serum creatinine, and liver enzymes. However, per patient analysis identified significant role of individual voriconazole dose and drug form change on measured plasma concentration. Measured voriconazole concentrations did not correlate with the treatment outcome of patients with IA. We only identified a limited number of adverse events related to voriconazole therapy; however, the median plasma concentration was not different from concentrations measured in samples without reported toxicity. Our retrospective study has suggested that routine monitoring of voriconazole plasma concentrations has probably only a limited role in daily haematological practice.

Infektionen

Trotz Weiterentwicklung moderner Antibiotika in den letzten Jahren sind die Letalitätszahlen der bakteriellen (eitrigen) Meningitis weiterhin hoch; Überlebende haben häufig neurologische Residuen. Die ungünstigen klinischen Verläufe der bakteriellen Meningitis sind meist Folge intrakranieller Komplikationen, wie z. B. eines generalisierten Hirnödems, einer zerebrovaskulären arteriellen oder venösen Beteiligung oder eines Hydrozephalus.

Prospective observational evaluation of incidences and implications of drug-drug interactions induced adverse drug reactions in critically ill patients

The primary aim of this study is to identify and analyze the importance of adverse drug reaction due to drug-drug interaction as a contributing factor towards drug safety. Patients more than 18 years of age admitted in multidisciplinary intensive care unit of a tertiary care hospital were included in this study. Patients who stayed less than 48 h and patients in whom all treatment modalities have been withdrawn and were on comfort measures only (no drugs were prescribed), were excluded. All the drugs that were given during intensive care unit stay were checked for presence of potential interactions which led to adverse drug reaction. Drug-drug interactions that were detected clinically or through investigations were recorded and also any therapeutic actions taken for drug-drug interactions were noted. From June 2006 to April 2007, 400 patients-prescriptions were analyzed. Adverse drug reactions due to drug-drug interactions were identified in 64% patients. Among those patients 38.67% had a single drug-drug interaction. Potential drug-drug interactions were 602. Clinically significant drug-drug interactions among the potential were 208 (34.55%). Clinically relevant drug-drug interactions were 103 (49.52% of 208 episodes). The adverse drug reactions due to drug-drug interactions in our sample were managed either by substituting another drug (50.48% of 103 episodes) or by adjusting the dose (1% of 103 episodes) or by omitting the drug (48.54% of 103 episodes). Among the 208 observed drug-drug interactions induced adverse drug reactions 21.63% was severe drug-drug interactions induced adverse drug reactions, 23.08% was moderate drug-drug interactions induced adverse drug reactions and 55.29% was minor drug-drug interactions induced adverse drug reactions. The interactions which were life threatening and/ or require medical intervention to minimize or prevent serious adverse effects were considered as severe drug-drug interactions and those interaction which resulted in an exacerbation of the patient's condition and/ or require an alteration in therapy were considered as moderate drug-drug interactions. The interactions which were limited clinical effects and manifestations may include an increase in the frequency or severity of side effects but generally would not require a major alteration in therapy were classified as minor drug-drug interactions. The correlation coefficient was 0.86 between the number of drugs given to the patient & number of average potential adverse drug reactions found among the patients. Increase in number of prescribed drug significantly (one way) increases number of potential adverse drug reaction due to drug-drug interaction (p<0.0001). Critically ill patients are more susceptible to drug-drug interactions due to the administration of multiple drugs and complex drug combinations. Several drug-drug interactions were clinically irrelevant.

Monitoring trough concentration of voriconazole is important to ensure successful antifungal therapy and to avoid hepatic damage in patients with hematological disorders

We investigated the role of therapeutic dose monitoring (TDM) in the treatment of fungal infections with voriconazole through 49 analyses of 34 patients who received treatment for hematologic diseases. Voriconazole concentration was highly variable among patients regardless of renal, liver functions, or age, and the effect of dose enhancement was not constant. This indicates the difficulty of predicting voriconazole concentration without TDM. We evaluated the outcome with the composite assessment system where patients were assumed non-responders when they failed to show improvement in at least 2 of the following 3 criteria: clinical, radiologic, and mycologic. We showed that concentration-response relationship depended on the status of underlying hematologic diseases; this relationship was observed only in cases without refractory hematologic diseases, but not in those with refractory diseases. In the former group, cases with >2 mg/L of concentration were associated with good response to voriconazole. On the other hand, elevation of hepatic enzyme was frequently observed when voriconazole concentration was >6 mg/L. From these results, we concluded that TDM should be executed and targeted to 2-6 mg/L to improve efficacy and to avoid side effects.

Intravitreal Voriconazole for the Treatment of Endogenous Aspergillus Endophthalmitis

OBJECTIVE

To describe the first use of intravitreal voriconazole in a human eye for the treatment of Aspergillus endophthalmitis.

DESIGN

Interventional case report.

PATIENT

A 22-year-old woman receiving immunosuppressive agents 5 weeks after lung transplantation who presented with blurred vision and redness in the right eye.

INTERVENTIONS

Intravitreal injection of voriconazole (100 microg/0.1 ml) with pars plana vitrectomy, given after isolation of A. terreus in the vitreous sample. Previous treatment modalities, including vitrectomy with repeated intravitreal amphotericin B and systemic voriconazole, failed to prevent deterioration.

MAIN OUTCOME MEASURES

Visual acuity (VA) and ocular inflammation.

RESULTS

Significant improvement was observed in VA (to 6/15) and in ocular inflammatory reaction. The patient recovered with no evidence of systemic fungal infection.

CONCLUSION

Intravitreal voriconazole may be used as an adjunct to systemic treatment in patients with Aspergillus endophthalmitis. Further clinical studies are needed to determine how often this approach can safely treat this condition.