Real-life experience with IV dalbavancin in Canada; results from the CLEAR (Canadian LEadership on Antimicrobial Real-life usage) registry.

OBJECTIVES: We report the use of IV dalbavancin in Canadian patients using data captured by the national CLEAR registry. METHODS: The CLEAR registry uses the web-based data management program, REDCapTM (online survey https://rcsurvey.radyfhs.umanitoba.ca/surveys/?s=TPMWJX98HL) to facilitate clinicians entering details associated with their clinical experiences using IV dalbavancin. RESULTS: Data were available for 40 patients. The most common infections treated were acute bacterial skin and skin structure infection (ABSSSI) (62.5% of patients), bone/joint infection (22.5%), bloodstream/vascular infection (7.5%) and endocarditis (5.0%). Dalbavancin was used as directed (75.0%) and empiric therapy (25.0%). MRSA was the most common identified pathogen (70.0%). Dalbavancin was used both in outpatient (e.g., emergency department) (65.0%), and inpatient treatment settings (e.g., hospital ward) (35.0%). Dalbavancin was used due to the convenience of a single dose treatment (77.5%) as well as to facilitate hospital discharge (7.5%). Dalbavancin was primarily used alone (90.0%), and most commonly using a single 1500 mg dose (77.5%). Microbiological success (pathogen eradicated or presumed eradicated) occurred in 88.2% of known cases, while clinical success (cure and/or improvement) occurred in 93.3% of known cases. No adverse events were reported. CONCLUSIONS: In Canada, IV dalbavancin is used as both directed and empiric therapy to treat ABSSSI as well as off-label (bone/joint, bacteremia/vascular, endocarditis, device-related) infections. It is used in both outpatient and inpatient settings due primarily to its convenience as a single-dose treatment regimen and to facilitate early hospital discharge. Dalbavancin use is associated with high microbiological and clinical cure rates along with an excellent safety profile.

Gordonia sputi-associated bloodstream infection in a renal transplant patient with chronic indwelling central venous catheter: a case report and literature review.

Introduction: Although rare, human infections caused by Gordonia spp. have been reported, especially within the immunocompromised population and those with long-term indwelling devices. We report a case of Gordonia spp. bacteraemia in a renal transplant patient and present a literature review on microbiological identification methods of this organism. Case Presentation: A 62-year-old female renal transplant recipient admitted to hospital with a 2-month history of dry cough and fevers occurring weekly when receiving electrolyte replacement infusions via a Groshong line. Over 2 weeks, blood cultures repeatedly isolated a Gram-positive bacillus solely in aerobic bottles, and this was initially reported as Rhodococcus spp. by the local microbiology laboratory. Chest computed tomography (CT) showed multiple ground-glass lung opacities suggestive of septic pulmonary emboli. As central line-associated bloodstream infection was suspected, empirical antibiotics were initiated and the Groshong line was removed. The Gram-positive bacillus was later confirmed by the reference laboratory as Gordonia sputi via 16S rRNA sequencing. Vancomycin and ciprofloxacin for a duration of 6 weeks were completed as targeted antimicrobial therapy. After treatment, the patient remained symptom-free with marked improvement on repeat CT chest imaging. Conclusion: This case illustrates the challenges surrounding identification of Gordonia spp. and other aerobic actinomycetes. 16S rRNA gene sequencing may be a preferred identification method, especially when initial workup of a weakly acid-fast organism fails to make an identification or shows discrepant results using traditional diagnostic modalities.

Novel six-month all oral treatment of pre-extensively drug-resistant tuberculosis in Canada: New treatment options present new implementation challenges.

Drug-resistant tuberculosis (TB) is a major global health challenge in part because there are fewer effective treatments and these treatments have been prolonged and more toxic. The evidence base for more effective, shorter, standardized treatments is evolving rapidly. Herein, we report the first case of pre-extensively drug-resistant pulmonary TB treated with a novel six-month all oral bedaquiline, pretomanid and linezolid (BPaL) regimen in Canada. Recent clinical trial data supporting BPaL therapy is presented in the context of current and evolving clinical guidelines. In this article, we highlight significant implementation challenges and make recommendations for what needs to be addressed to ensure safe programmatic use of BPaL in Canada. Key recommendations include the development of infrastructure for timely access to novel TB drug susceptibility testing, streamlining access to novel TB drugs, and cautious use of such drugs in collaboration with care teams with expertise in drug-resistant TB management.

Self-injecting non-prescribed substances into vascular access devices: a case study of one health system's ongoing journey from clinical concern to practice and policy response.

BACKGROUND: Overdose-associated deaths and morbidity related to substance use is a global public health emergency with devastating social and economic costs. Complications of substance use are most pronounced among people who inject drugs (PWID), particularly infections, resulting in increased risk of hospitalization. PWID often require intravenous access for medical treatments such as antibiotics; however, vascular access may be limited due to the impacts of long-term self-venipuncture. While vascular access devices including peripherally inserted central catheters (PICCs) allow reliable and sustained routes of administration for indicated therapies, the use of PICCs among PWID presents unique challenges. The incidence and risks associated with self-injecting non-prescribed substances into vascular access devices (SIVAD) is one such concern for which there is limited evidence and absence of formal practice guidance. CASE PRESENTATION: We report the experience of a multidisciplinary team at a health organization in Vancouver, Canada, working to characterize the incidence, patient and healthcare provider perspectives, and overall impact of SIVAD. The case study of SIVAD begins with a patient's perspective, including patient rationale for SIVAD, understanding of risks and the varying responses given by healthcare providers following disclosure of SIVAD. Using the limited literature available on the subject, we summarize the intersection of SIVAD and substance use and outline known and anticipated health risks. The case study is further contextualized by experience from a Vancouver in-hospital Overdose Prevention Site (OPS), where 37% of all individual visits involve SIVAD. The case study concludes by describing the systematic process by which local clinical guidance for SIVAD harm reduction was developed with stakeholder engagement, medical ethics consultation, expert consensus guideline development and implementation with staff education and planned research evaluation. CONCLUSION: SIVAD is encountered with enough frequency in an urban healthcare setting in Vancouver, Canada, to warrant an organizational approach. This case study aims to enhance appreciation of SIVAD as a common and complex clinical issue with anticipated health risks. The authors conclude that using a harm reduction lens for SIVAD policy and research can provide benefit to clinicians and patients by offering a clear and a consistent healthcare response to this common issue.

Program-wide review and follow-up of erythema Induratum of Bazin and tuberculosis-associated ocular inflammation management in a TB low-incidence setting: need for improved treatment candidate selection, therapy standardization, and care collaboration.

BACKGROUND: Erythema induratum of Bazin (EIB) - nodular vasculitis associated with Mycobacterium tuberculosis (TB) - and Tuberculosis-Associated Ocular Inflammation (TB-AOI) represent uncommon manifestations of TB. There is limited data and a lack of diagnostic and treatment standards for these conditions. METHODS: Eleven-year retrospective review of EIB and TB-AOI cases managed in a provincial TB program with prospective phone-based follow-up of anti-tubercular therapy (ATT) recipients. Presumptive TB-AOI and EIB diagnoses were determined by ophthalmologist or dermatologist assessments correlated with positive tuberculin skin test and/or QuantiFERON-TB Gold, along with pathologic criteria in EIB cases. RESULTS: Of 21 EIB and 20 TB-AOI cases that received ATT, 13 and 11, respectively, were reached for follow-up. The majority of EIB and TB-AOI cases were female and immigrated from TB high-burden countries. Median durations of pre-diagnosis symptoms were 2 and 0.8 years (IQR 2.5 & 1.1) for EIB and TB-AOI cases, respectively. Overall, 14 different ATT regimens were used for a median duration of 6 months (range 5-9). ATT related adverse events resulting in treatment discontinuation occurred in 14% of EIB and 10% of TB-AOI cases. On last follow-up, 76% of EIB and 42% of TB-AOI had improvement or resolution of disease. CONCLUSION: EIB and TB-AOI were uncommon presentations receiving variable therapy. While treatment response was modest for EIB cases, TB-AOI cases had sub-optimal treatment outcomes. The unique diagnostic and management challenges presented by these conditions in TB low-incidence settings highlight a need for improved treatment candidate selection, therapy standardization, and cross-specialty medical collaboration.

Healthcare contacts among patients lost to follow-up in HIV care: review of a large regional cohort utilizing electronic health records.

In the United States 40% of HIV patients are lost to follow-up (LTFU) following linkage to HIV care and an estimated 30-61% of new HIV transmissions are attributed to this group. To characterize those LTFU and healthcare contacts they make, we retrospectively analyzed a large regional HIV cohort in Calgary, Canada, utilizing a province-wide electronic health record. Adults engaged in HIV care between January 2010 and August 2014 who had >12 months without HIV clinic contact were identified as LTFU. Of 1928 individuals engaged in care, 176 became LTFU with 64% having no healthcare contacts, 20% receiving HIV care elsewhere, and 16% making non-HIV healthcare contacts. Those LTFU making non-HIV healthcare contacts did so a median of six times (interquartile range 2-8), 76% attending emergency departments (ED). Compared to those retained in care, LTFU patients were younger (median age 43 versus 47 years), had lower CD4+ cell counts (median 420 versus 500 × 106/l) and more commonly resided outside of the centralized HIV clinic's city (odds ratio 4.58) (all p < 0.01). Our finding that a majority of those LTFU did not make healthcare contacts suggests that community and HIV clinic-based relinkage programs are needed. For those LTFU who make healthcare contacts enhanced ED-based relinkage programs could engage a majority.

Acute dental infections managed in an outpatient parenteral antibiotic program setting: prospective analysis and public health implications.

BACKGROUND: The number of Acute Dental Infections (ADI) presenting for emergency department (ED) care are steadily increasing. Outpatient Parenteral Antibiotic Therapy (OPAT) programs are increasingly utilized as an alternative cost-effective approach to the management of serious infectious diseases but their role in the management of severe ADI is not established. This study aims to address this knowledge gap through evaluation of ADI referrals to a regional OPAT program in a large Canadian center. METHODS: All adult ED and OPAT program ADI referrals from four acute care adult hospitals in Calgary, Alberta, were quantified using ICD diagnosis codes in a regional reporting system. Citywide OPAT program referrals were prospectively enrolled over a five-month period from February to June 2014. Participants completed a questionnaire and OPAT medical records were reviewed upon completion of care. RESULTS: Of 704 adults presenting to acute care facilities with dental infections during the study period 343 (49%) were referred to OPAT for ADI treatment and 110 were included in the study. Participant mean age was 44 years, 55% were women, and a majority of participants had dental insurance (65%), had seen a dentist in the past six months (65%) and reported prior dental infections (77%), 36% reporting the current ADI as a recurrence. Median length of parenteral antibiotic therapy was 3 days, average total course of antibiotics was 15-days, with a cumulative 1326 antibiotic days over the study period. There was no difference in total duration of antibiotics between broad and narrow spectrum regimes. Conservative cost estimate of OPAT care was $120,096, a cost savings of $597,434 (83%) compared with hospitalization. CONCLUSIONS: ADI represent a common preventable cause of recurrent morbidity. Although OPAT programs may offer short-term cost savings compared with hospitalization, risks associated with extended antibiotic exposures and delayed definitive dental management must also be gauged.

The discovery of macrocyclic XIAP antagonists from a DNA-programmed chemistry library, and their optimization to give lead compounds with in vivo antitumor activity.

Affinity selection screening of macrocycle libraries derived from DNA-programmed chemistry identified XIAP BIR2 and BIR3 domain inhibitors that displace bound pro-apoptotic caspases. X-ray cocrystal structures of key compounds with XIAP BIR2 suggested potency-enhancing structural modifications. Optimization of dimeric macrocycles with similar affinity for both domains were potent pro-apoptotic agents in cancer cell lines and efficacious in shrinking tumors in a mouse xenograft model.

Lymphomatoid granulomatosis associated with azathioprine therapy in Crohn disease.

BACKGROUND: Lymphomatoid granulomatosis (LYG) is a rare Epstein-Barr virus-associated lymphoproliferative disorder. It most often occurs in patients with immunodeficiency and the clinical course ranges from indolent behavior to that of an aggressive malignancy. Pulmonary, central nervous system and dermatological manifestations are most common. To our knowledge this is the first reported case of LYG related to azathioprine therapy in Crohn disease. CASE PRESENTATION: A twenty-six year old Caucasian woman with colonic Crohn disease on maintenance azathioprine therapy presented with right upper quadrant pain and fever. Diagnostic imaging revealed extensive liver, pulmonary and cerebral lesions. A diagnosis of LYG was made based on the pattern of organ involvement and the immunohistochemical features on liver and lung biopsy. CONCLUSIONS: Thiopurine therapy for inflammatory bowel disease is associated with an increased incidence of lymphoproliferative disorders. This report highlights the diagnostic challenges associated with LYG. As long-term thiopurine therapy remains central to the management of inflammatory bowel diseases it is essential that both patients and clinicians are aware of this potential adverse outcome.

Molecular details of quinolone-DNA interactions: solution structure of an unusually stable DNA duplex with covalently linked nalidixic acid residues and non-covalent complexes derived from it.

Quinolones are antibacterial drugs that are thought to bind preferentially to disturbed regions of DNA. They do not fall into the classical categories of intercalators, groove binders or electrostatic binders to the backbone. We solved the 3D structure of the DNA duplex (ACGCGU-NA)2, where NA denotes a nalidixic acid residue covalently linked to the 2'-position of 2'-amino-2'-deoxyuridine, by NMR and restrained torsion angle molecular dynamics (MD). In the complex, the quinolones stack on G:C base pairs of the core tetramer and disrupt the terminal A:U base pair. The displaced dA residues can stack on the quinolones, while the uracil rings bind in the minor groove. The duplex-bridging interactions of the drugs and the contacts of the displaced nucleotides explain the high UV-melting temperature for d(ACGCGU-NA)2 of up to 53 degrees C. Further, non-covalently linked complexes between quinolones and DNA of the sequence ACGCGT can be generated via MD using constraints obtained for d(ACGCGU-NA)2. This is demonstrated for unconjugated nalidixic acid and its 6-fluoro derivative. The well-ordered and tightly packed structures thus obtained are compatible with a published model for the quinolone-DNA complex in the active site of gyrases.

Synthesis of oligonucleotides with a 2'-cap at the 3'-terminus via reversed phosphoramidites.

[reaction: see text] A method is presented for the synthesis of single compounds or small combinatorial libraries of oligonucleotides with 2'-acylamido-2'-deoxyuridine residues at the 3'-terminus. Selection experiments identified the residue of anthraquinone-2-carboxylic acid as a "molecular cap" that increases the UV melting point of the duplex (5'-ACGCGU-3')(2) by up to 28 degrees C compared to the unmodified control duplex.

On the effect of covalently appended quinolones on termini of DNA duplexes.

Quinolones are gyrase inhibitors that are widely used as antibiotics in the clinic. When covalently attached to oligonucleotides as 5'-acylamido substituents, quinolones were found to stabilize duplexes of oligonucleotides against thermal denaturation. For short duplexes, such as qu-T*GCGCA, where qu is a quinolone residue and T is a 5'-amino-5'-deoxythymidine residue, an increase in the UV melting point of up to 27.8 degrees C was measured. The stabilizing effect was demonstrated for all quinolones tested, namely nalidixic acid, oxolinic acid, pipemidic acid, cinoxacin, norfloxacin, and ofloxacin. The three-dimensional structure of (oa-T*GCGCA)2, where oa is an oxolinic acid residue, was solved by two-dimensional NMR spectroscopy and restrained molecular dynamics. In this complex, the oxolinic acid residues disrupt the terminal T1:A6 base pairs and stack on the G2:C5 base pairs. The displaced adenosine residues bind in the minor groove of the core duplex, while the thymidine residues pack against the oxolinic acid residues. The "molecular cap" thus formed fits tightly on the G:C base pairs, resulting in increased base-pairing fidelity, as demonstrated in UV melting experiments with the sequence oa-T*GGTTGAC and target strands containing a mismatched nucleobase. The structure of the "molecular cap" with its disrupted terminal base pair may also be helpful for modeling how quinolones block re-ligation of DNA strands in the active site of gyrases.