Therapeutic Switching of Rafoxanide: a New Approach To Fighting Drug-Resistant Bacteria and Fungi

Control and management of life-threatening bacterial and fungal infections are a global health challenge. Despite advances in antimicrobial therapies, treatment failures for resistant bacterial and fungal infections continue to increase. We aimed to repurpose the anthelmintic drug rafoxanide for use with existing therapeutic drugs to increase the possibility of better managing infection and decrease treatment failures. For this purpose, we evaluated the antibacterial and antifungal potential of rafoxanide. Notably, 70% (70/100) of bacterial isolates showed multidrug resistance (MDR) patterns, with higher prevalence among human isolates (73.5% [50/68]) than animal ones (62.5% [20/32]). Moreover, 22 fungal isolates (88%) were MDR and were more prevalent among animal (88.9%) than human (87.5%) sources. We observed alarming MDR patterns among bacterial isolates, i.e., Klebsiella pneumoniae (75% [30/40; 8 animal and 22 human]) and Escherichia coli (66% [40/60; 12 animal and 28 human]), and fungal isolates, i.e., Candida albicans (86.7% [13/15; 4 animal and 9 human]) and Aspergillus fumigatus (90% [9/10; 4 animal and 5 human]), that were resistant to at least one agent in three or more different antimicrobial classes. Rafoxanide had antibacterial and antifungal activities, with minimal inhibitory concentration (MICs) ranging from 2 to 128 μg/mL. Rafoxanide at sub-MICs downregulated the mRNA expression of resistance genes, including E. coli and K. pneumoniae blaCTX-M-1, blaTEM-1, blaSHV, MOX, and DHA, C. albicans ERG11, and A. fumigatus cyp51A. We noted the improvement in the activity of β-lactam and antifungal drugs upon combination with rafoxanide. This was apparent in the reduction in the MICs of cefotaxime and fluconazole when these drugs were combined with sub-MIC levels of rafoxanide. There was obvious synergism between rafoxanide and cefotaxime against all E. coli and K. pneumoniae isolates (fractional inhibitory concentration index [FICI] values ≤ 0.5). Accordingly, there was a shift in the patterns of resistance of 16.7% of E. coli and 22.5% of K. pneumoniae isolates to cefotaxime and those of 63.2% of C. albicans and A. fumigatus isolates to fluconazole when the isolates were treated with sub-MICs of rafoxanide. These results were confirmed by in silico and mouse protection assays. Based on the in silico study, one possible explanation for how rafoxanide reduced bacterial resistance is through its inhibitory effects on bacterial and fungal histidine kinase enzymes. In short, rafoxanide exhibited promising results in overcoming bacterial and fungal drug resistance. IMPORTANCE The drug repurposing strategy is an alternative approach to reducing drug development timelines with low cost, especially during outbreaks of disease caused by drug-resistant pathogens. Rafoxanide can disrupt the abilities of bacterial and fungal cells to adapt to stress conditions. The coadministration of antibiotics with rafoxanide can prevent the failure of treatment of both resistant bacteria and fungi, as the resistant pathogens could be made sensitive upon treatment with rafoxanide. From our findings, we anticipate that pharmaceutical companies will be able to utilize new combinations against resistant pathogens.

Clinical Efficacy of Fidaxomicin and Oral Metronidazole for Treating Clostridioides difficile Infection and the Associated Recurrence Rate: A Retrospective Cohort Study

Clostridioides difficile infection (CDI) has significant implications for healthcare economics. Although clinical trials have compared fidaxomicin (FDX) and vancomycin, comparisons of FDX and oral metronidazole (MNZ) are limited. Therefore, we compared the therapeutic effects of FDX and oral MNZ. Patients diagnosed with CDI between January 2015 and March 2023 were enrolled. Those treated with oral MNZ or FDX were selected and retrospectively analyzed. The primary outcome was the global cure rate. Secondary outcomes included factors contributing to the CDI global cure rate; the rate of medication change owing to initial treatment failure; and incidence rates of clinical cure, recurrence, and all-cause mortality within 30 days. Of the 264 enrolled patients, 75 and 30 received initial oral MNZ and FDX treatments, respectively. The corresponding CDI global cure rates were 53.3% and 70% (p = 0.12). In multivariate analysis, FDX was not associated with the global cure rate. In the MNZ group, 18.7% of the patients had to change medications owing to initial treatment failure. The FDX group had a higher clinical cure rate and lower recurrence rate than the MNZ group, although not significant. However, caution is necessary owing to necessary treatment changes due to MNZ failure.

Potential Implication of Azole Persistence in the Treatment Failure of Two Haematological Patients Infected with Aspergillus fumigatus

Invasive aspergillosis (IA) is a major cause of morbidity and mortality in patients receiving allogeneic haematopoieticcell transplantation. The deep immunosuppression and a variety of potential additional complications developed in these patients result in IA reaching mortality rates of around 50-60%. This mortality is even higher when the patients are infected with azole-resistant isolates, demonstrating that, despite the complexity of management, adequate azole treatment can have a beneficial effect. It is therefore paramount to understand the reasons why antifungal treatment of IA infections caused by azole-susceptible isolates is often unsuccessful. In this respect, there are already various factors known to be important for treatment efficacy, for instance the drug concentrations achieved in the blood, which are thus often monitored. We hypothesize that antifungal persistence may be another important factor to consider. In this study we present two case reports of haematological patients who developed proven IA and suffered treatment failure, despite having been infected with susceptible isolates, receiving correct antifungal treatment and reaching therapeutic levels of the azole. Microbiological analysis of the recovered infective isolates showed that the patients were infected with multiple strains, several of which were persisters to voriconazole and/or isavuconazole. Therefore, we propose that azole persistence may have contributed to therapeutic failure in these patients and that this phenomenon should be considered in future studies.

Highly active antiretroviral therapy discontinuation time is associated with therapeutic failure among human immunodeficiency virus (HIV)-infected immigrant adults: A cohort study from a Peruvian referral hospital during the Venezuelan exodus

OBJECTIVE

To evaluate the association between Highly Active Antiretroviral Therapy (HAART) discontinuation time and therapeutic failure (TF) in Venezuelan immigrants with HIV that restart HAART.

METHODS

We carried out a retrospective cohort study in a large hospital in Peru. We included Venezuelan immigrants who restarted HAART and were followed over at least 6 months. The primary outcome was TF. Secondary outcomes were immunologic (IF), virologic (VF) and clinical (CF) failures. The exposure variable was HAART discontinuation, categorised as no discontinuation, less than 6 months, and 6 months or more. We applied generalised linear models Poisson family with robust standard errors to calculate crude (cRR) and adjusted (aRR) relative risks by statistical and epidemiological criteria.

RESULTS

We included 294 patients, 97.2% were males, and the median age was 32 years. Out of all the patients, 32.7% discontinued HAART for less than 6 months, 15.0% discontinued for more than 6 months and the remaining 52.3% did not discontinue. The cumulative incidence of TF was 27.9%, 24.5% in VF, 6.0% in IF and 6.0% in CF. Compared with non-discontinued HAART patients, the discontinuation for less than 6 months (aRR = 1.98 [95% CI: 1.27-3.09]) and from 6 months to more (aRR = 3.17 [95% CI: 2.02-4.95]) increased the risk of TF. Likewise, treatment discontinuation of up to 6 months (aRR = 2.32 [95% CI: 1.40-3.84]) and from 6 months to more (aRR = 3.93 [95% CI: 2.39-6.45]) increased the risk of VF.

CONCLUSIONS

HAART discontinuation increases the probability of TF and VF in Venezuelan immigrants.

LONEPINELLA SP. ISOLATED FROM WOUND INFECTIONS OF KOALAS

We describe two cases of wound infections of koalas (Phascolarctos cinereus), one wild and one captive, in which Lonepinella-like organisms were involved. The wild adult koala was captured with bite wound injuries, as part of a koala population management program in Queensland, Australia. In both cases, there was evidence of physical trauma causing the initial wound. The captive koala suffered injury from the cage wire, and the wild koala had injuries suggestive of intermale fighting. Gram-negative bacteria isolated from both cases proved to be challenging to identify using routine diagnostic tests. The wound in the captive koala yielded a pure culture of an organism shown by whole genome sequence (WGS) analysis to be a member of the genus Lonepinella, but not a member of the only formally described species, L. koalarum. The wound of the wild koala yielded a mixed culture of Citrobacter koseri, Enterobacter cloacae and an organism shown by WGS analysis to be Lonepinella, but again not Lonepinella koalarum. Both cases were difficult to treat; the captive koala eventually had to have the phalanges amputated, and the wild koala required removal of the affected claw. The two Lonepinella isolates from these cases have a close relationship to an isolate from a human wound caused by a koala bite and may represent a novel species within the genus Lonepinella. Wound infections in koalas linked to Lonepinella have not been reported previously. Wildlife veterinarians need to be aware of the potential presence of Lonepinella-like organisms when dealing with wound infections in koalas, and the inability of commercial kits and systems to correctly identify the isolates.

Novel signatures of prostate cancer progression and therapeutic resistance

INTRODUCTION

The extensive heterogeneity of prostate cancer (PCa) and multilayered complexity of progression to castration-resistant prostate cancer (CRPC) have contributed to the challenges of accurately monitoring advanced disease. Profiling of the tumor microenvironment with large-scale transcriptomic studies have identified gene signatures that predict biochemical recurrence, lymph node invasion, metastases, and development of therapeutic resistance through critical determinants driving CRPC.

AREAS COVERED

This review encompasses understanding of the role of different molecular determinants of PCa progression to lethal disease including the phenotypic dynamic of cell plasticity, EMT-MET interconversion, and signaling-pathways driving PCa cells to advance and metastasize. The value of liquid biopsies encompassing circulating tumor cells and extracellular vesicles to detect disease progression and emergence of therapeutic resistance in patients progressing to lethal disease is discussed. Relevant literature was added from PubMed portal.

EXPERT OPINION

Despite progress in the tumor-targeted therapeutics and biomarker discovery, distant metastasis and therapeutic resistance remain the major cause of mortality in patients with advanced CRPC. No single signature can encompass the tremendous phenotypic and genomic heterogeneity of PCa, but rather multi-threaded omics-derived and phenotypic markers tailored and validated into a multimodal signature.

Amantadine in Treatment of Dysthymia-The Pilot Case Series Study

Dysthymia is a common chronic mood disorder in which isolated symptoms of depression persist for at least 2 years. Despite the many medications recommended for the treatment of dysthymia, no recommendations have yet been made for the treatment of patients who fail to achieve clinical improvement. This justifies attempts to identify second-line drugs for the treatment of dysthymia. In an open and naturalistic case study, five patients diagnosed with dysthymia in whom at least one antidepressant treatment was ineffective were treated with amantadine. In the age- and gender-matched external control group, patients were treated with sertraline at 100 mg/day. Depressive symptoms were assessed using HDRS-17. Two men and three women were treated with 100 mg amantadine for 3 months with 3-5 months follow-up. After 1 month of treatment with amantadine, a significant reduction in the intensity of depressive symptoms was achieved in all patients, and the clinical improvement increased over the next 2 months of treatment. No deterioration in well-being was observed in any patient after discontinuation of amantadine. The effect of amantadine treatment was comparable to that of sertraline treatment in patients with dysthymia who improved with this drug. The present study indicates that amantadine is an effective and well-tolerated drug in the treatment of dysthymia. Amantadine may be associated with a quick improvement in symptoms in the treatment of dysthymia. Treatment with this drug seems to be associated with good tolerability and persistency of the therapeutic effect after the discontinuation of the treatment.

Outcomes of Intravenous Push versus Intermittent Infusion Administration of Cefepime in Critically Ill Patients

The equivalence of intravenous push (IVP) and piggyback (IVPB) administration has not been evaluated in the critically ill population for most medications, but it is especially relevant for antibiotics, such as cefepime, that exhibit time-dependent bactericidal activity. A single center, retrospective, observational pre/post-protocol change study included critically ill adults who received cefepime as empiric therapy between August 2015 and 2021. The primary outcome was treatment failure, which was defined as a composite of escalation of antibiotic regimen or all-cause mortality. Secondary outcomes included adverse drug events, days of cefepime therapy, total days of antibiotic therapy, and ICU and hospital length of stay. Outcomes were compared using Chi-squared, Mann Whitney U, and binary logistic regression as appropriate. A total of 285 patients were included: 87 IVPB and 198 IVP. Treatment failure occurred in 18% (n = 16) of the IVPB group and 27% (n = 54) of the IVP group (p = 0.109). There were no significant differences in secondary outcomes. Longer duration of antibiotics (odds ratio [OR] 1.057, 95% confidence interval [CI] 1.013-1.103), SOFA score (OR 1.269, 95% CI 1.154-1.397) and IVP administration of cefepime (OR 2.370, 95% CI 1.143-4.914) were independently associated with treatment failure. Critically ill patients who received IVP cefepime were more likely to experience treatment failure in an adjusted analysis. The current practice of IVP cefepime should be reevaluated, as it may not provide similar clinical outcomes in the critically ill population.

Reintervention, PROMs, and Factors Influencing PROMs Following Surgery for de Quervain's Tenosynovitis

Objective  The aims of this study are to describe and identify the factors that influence patient reported outcomes following surgery of de Quervain's tenosynovitis. The secondary objective is to report the rate of reintervention following surgery of de Quervain's tenosynovitis. Patients and Methods  Outcomes using the numerical rating scale (NRS) for pain, Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH), Patient-Rated Wrist Evaluation (PRWE), the Patients Reported Outcome Measurement Information System Pain Interference (PROMIS PI), and a custom de Quervain's questionnaire were obtained. A multivariable linear regression analysis was performed to identify independent factors associated with patient-reported outcomes. Results  Seventy-six patients who underwent de Quervain's release participated. The average age was 52.8 years (95% confidence interval: 49.6-56.1) and median follow-up age was 7.0 years (interquartile range [IQR]: 4.3-12.0). Outcomes were: NRS of pain was 0 (IQR: 0.0-3.0), the median QuickDASH was 6.82 (IQR: 0.00-28.41), the median PRWE score was 4.0 (IQR: 0.00-18.50), and the median PROMIS PI score was 43.90 (IQR: 38.70-53.90). Eighteen (23.7%) of the patients reported pain with thumb activities, four of whom had a reintervention. Additionally, 21 (26.9%) patients reported decreased strength in the thumb compared to the contralateral side, of which two underwent a reintervention. In total, eight patients underwent reintervention of which seven had a second surgery and one had a cortisone injection. Conclusion  Roughly 1 in 20 patients following de Quervain's release undergoes reintervention. Patients with high PROMIS PI scores report poor surgical outcomes more frequently. Patients with high PROMIS PI scores report higher NRS pain scores ( p  < 0.05), higher QuickDASH scores ( p  < 0.05), and higher PRWE scores ( p  < 0.05). In practice, careful consideration of PROMIS PI scores and psychosocial factors are recommended before considering reintervention.

A retrospective study of initial root canal treatment failure in maxillary premolars via using cone-beam computed tomography

BACKGROUND

This case-series study examined canal morphology and common factors for endodontic failure in maxillary first and second premolars that were referred for retreatment owing to clinical symptoms or radiographic signs.

METHODS

Records were retrospectively searched using Current Dental Terminology codes to identify maxillary first and second premolars with endodontic failure. Periapical and cone-beam computed tomographic images were examined to determine Vertucci classifications and suspected factors related to treatment failure.

RESULTS

A total of 235 teeth from 213 patients were included for evaluation. The following Vertucci classification of canal configurations were observed for maxillary first and second premolars: type I (1-1) (4.6% and 32.0%, respectively), type II (2-1) (15.9% and 27.9%, respectively), type III (2-2) (76.1% and 36.1%, respectively), type IV (1-2) (0% and 2%, respectively), and type V (3) (3.4% and 2%, respectively). More treatment failures were noticed in maxillary second premolars than first premolars and in females than in males. The 4 most common factors related to failure were inadequate filling, restorative failure, vertical root fracture, and missed canals. Missed canals were more frequently identified in maxillary second premolars (21.8%) than first premolars (11.4%) (P = .044).

CONCLUSIONS

Multiple factors are associated with primary root canal treatment failures in maxillary premolars. Variations in canal morphology appear to be underappreciated in maxillary second premolars.

PRACTICAL IMPLICATIONS

Maxillary second premolars have more complicated canal configurations than first premolars. Besides adequate filling, clinicians should give extra attention to anatomic variability in second premolars owing to higher failure incidence.

Phenotypic and Genotypic Antimicrobial Susceptibility Testing of Chlamydia trachomatis Isolates from Patients with Persistent or Clinical Treatment Failure in Spain

The aim of this multicentre project (seven hospitals across the Spanish National Health Service) was to study the phenotypic and genotypic susceptibility of C. trachomatis to the main antimicrobials used (macrolides, doxycycline, and quinolones) in isolates from patients with clinical treatment failure in whom reinfection had been ruled out. During 2018-2019, 73 clinical isolates were selected. Sixty-nine clinical specimens were inoculated onto confluent McCoy cell monolayers for phenotypic susceptibility testing. The minimum inhibitory concentration for azithromycin and doxycycline was defined as the lowest concentration associated with an at least 95% reduction in inclusion-forming units after one passage in the presence of the antibiotic compared to the initial inoculum for each strain (control). Sequencing analysis was performed for the genotypic detection of resistance to macrolides, analysing mutations in the 23S rRNA gene (at positions 2057, 2058, 2059, and 2611), and quinolones, analysing a fragment of the gyrA gene, and searching for the G248T mutation (Ser83->Ile). For tetracyclines, in-house RT-PCR was used to test for the tet(C) gene. The phenotypic susceptibility testing was successful for 10 isolates. All the isolates had minimum inhibitory concentrations for azithromycin ≤ 0.125 mg/L and for doxycycline ≤ 0.064 mg/L and were considered sensitive. Of the 73 strains studied, no mutations were found at positions T2611C or G248T of the gyrA gene. We successfully sequenced 66 isolates. No macrolide resistance-associated mutations were found at positions 2057, 2058, 2059, or T2611C. None of the isolates carried the tet(C) gene. We found no evidence for genomic resistance in this large, clinically relevant dataset.

Differences in Fertility-Related Quality of Life and Emotional Status Among Women Undergoing Different IVF Treatment Cycles

Objective

The present study aimed to provide more insight into the possible differences in the fertility-related quality of life (FertiQoL) and emotional status of women undergoing different cycles of in vitro fertilization (IVF) treatments.

Methods

A prospective cohort study was performed, and a total of 432 women undergoing IVF treatment were recruited. FertiQoL scale, self-rating anxiety scale (SAS), self-rating depression scale (SDS), and perceived social support scale (PSSS) were used to analyze fertility-related QoL and emotional status. Data were analyzed comparing women undergoing different cycles of IVF treatments.

Results

A significant decrease in FertiQoL scores occurred in women with increased cycles of IVF treatment. Both anxiety and depression scores significantly increased with increased cycles of attempting IVF treatment. There was no significant difference detected in perceived social support among groups.

Conclusion

With the increase in the number of IVF treatment cycles, women's FertiQoL gradually decreased, while the risk of anxiety and depression gradually increased.

Factors associated with treatment failure, and possible applications of probiotic bacteria in the arsenal against Helicobacter pylori

INTRODUCTION

Helicobacter pylori is a widespread helical Gram-negative bacterium, which causes a variety of stomach disorders, such as peptic ulcer, chronic atrophic gastritis, and gastric cancer. This microbe frequently colonizes the mucosal layer of the human stomach and survives in the inhospitable microenvironment, by adapting to this hostile milieu.

AREAS COVERED

In this extensive review, we describe conventional antibiotic treatment regimens used against H. pylori including, empirical, tailored, and salvage therapies. Then, we present state-of-the-art information about reasons for treatment failure against H. pylori. Afterward, the latest advances in the use of probiotic bacteria against H. pylori infection are discussed. Finally, we propose a polymeric bio-platform to provide efficient delivery of probiotics for H. pylori infection.

EXPERT OPINION

For effective probiotic delivery systems, it is necessary to avoid the early release of probiotics at the acidic stomach pH, to protect them against enzymes and antimicrobials, and precisely target H. pylori bacteria which have colonized the antrum area of the stomach (basic pH).

A Simple Preoperative Score Predicting Failure Following Decompression Surgery for Degenerative Lumbar Spinal Stenosis

BACKGROUND CONTEXT

Proper patient selection is crucial for the outcome of surgically treated degenerative lumbar spinal stenosis (DLSS). Nevertheless, there is still not a clear consensus regarding the optimal treatment option for patients with DLSS.

PURPOSE

To investigate the treatment failure rate and introduce a simple, preoperative score to aid surgical decision-making.

STUDY DESIGN/SETTING

Retrospective observational study.

PATIENT SAMPLE

Four hundred forty-five patients who underwent surgical decompression for DLSS.

OUTCOME MEASURES

Treatment failure (defined as conversion to a fusion of a previously decompressed level) of lumbar decompression.

MATERIALS AND METHODS

Several risk factors associated with worse outcomes and treatment failures, such as age, body mass index, smoking status, previous surgery, low back pain (LBP), facet joint effusion, disk degeneration, fatty infiltration of the paraspinal muscles, the presence of degenerative spondylolisthesis and the facet angulation, were investigated.

RESULTS

At a mean follow-up of 44±31 months, 6.5% (29/445) of the patients underwent revision surgery with spinal fusion at an average of 3±9 months following the lumbar decompression due to low back or leg pain. The baseline LBP (≥7) [odds ratio (OR)=5.4, P <0.001], the presence of facet joint effusion (>2 mm) in magnetic resonance imaging (OR=4.2, P <0.001), and disk degeneration (Pfirrmann >4) (OR=3.2, P =0.03) were associated with an increased risk for treatment failure following decompression for DLSS. The receiver operating characteristic curve analysis demonstrated that a score≥6 points yielded a sensitivity of 90% and specificity of 64% for predicting a treatment failure following lumbar decompression for DLSS in the present cohort.

CONCLUSIONS

The newly introduced score quantifying amounts of LBP, facet effusions, and disk degeneration, could predict treatment failure and the need for revision surgery for DLSS patients undergoing lumbar decompression without fusion. Patients with scores >6 have a high chance of needing fusion following decompression surgery.

LEVEL OF EVIDENCE

Retrospective observational study, Level III.

Drug resistance in Leishmania: does it really matter?

Treatment failure (TF) jeopardizes the management of parasitic diseases, including leishmaniasis. From the parasite's point of view, drug resistance (DR) is generally considered as central to TF. However, the link between TF and DR, as measured by in vitro drug susceptibility assays, is unclear, some studies revealing an association between treatment outcome and drug susceptibility, others not. Here we address three fundamental questions aiming to shed light on these ambiguities. First, are the right assays being used to measure DR? Second, are the parasites studied, which are generally those that adapt to in vitro culture, actually appropriate? Finally, are other parasite factors - such as the development of quiescent forms that are recalcitrant to drugs - responsible for TF without DR?

Weight-related malaria treatment failure with artemether-lumefantrine

A 52-year-old male with no past medical history travelled from Canada to Nigeria for work. Eight days after returning to Canada he experienced fevers and night sweats, and self-tested with a BinaxNow malaria kit (Abbott, Chicago, IL) that was positive for Plasmodium falciparum. He self-initiated treatment with four tablets of combined artemether (20 mg) and lumefantrine (120 mg) (AL) twice daily for three days. He was adherent to this therapy. His fevers abated and he made a self-described complete clinical recovery within 5 days. His symptoms returned two and a half weeks after completing AL and he presented to the Emergency Department with a temperature of 40 degrees Celsius, chills, lethargy, non-bloody diarrhoea, and back pain, and was admitted to hospital. Two malaria thick and thin smears confirmed Plasmodium falciparum with parasitemia of 0.4%. He was diagnosed with uncomplicated malaria and initiated on a three-day course of combined atovaquone (250 mg) plus proguanil (100 mg), four tablets per day for three days. He rapidly defervesced within 24 hours, his parasitemia resolved two days after initiating therapy, and had an uneventful and full recovery.

Aspergillus fumigatus Can Display Persistence to the Fungicidal Drug Voriconazole

Aspergillus fumigatus is a filamentous fungus that can infect the lungs of patients with immunosuppression and/or underlying lung diseases. The mortality associated with chronic and invasive aspergillosis infections remain very high, despite availability of antifungal treatments. In the last decade, there has been a worrisome emergence and spread of resistance to the first-line antifungals, the azoles. The mortality caused by resistant isolates is even higher, and patient management is complicated as the therapeutic options are reduced. Nevertheless, treatment failure is also common in patients infected with azole-susceptible isolates, which can be due to several non-mutually exclusive reasons, such as poor drug absorption. In addition, the phenomena of tolerance or persistence, where susceptible pathogens can survive the action of an antimicrobial for extended periods, have been associated with treatment failure in bacterial infections, and their occurrence in fungal infections already proposed. Here, we demonstrate that some isolates of A. fumigatus display persistence to voriconazole. A subpopulation of the persister isolates can survive for extended periods and even grow at low rates in the presence of supra-MIC of voriconazole and seemingly other azoles. Persistence cannot be eradicated with adjuvant drugs or antifungal combinations and seemed to reduce the efficacy of treatment for certain individuals in a Galleria mellonella model of infection. Furthermore, persistence implies a distinct transcriptional profile, demonstrating that it is an active response. We propose that azole persistence might be a relevant and underestimated factor that could influence the outcome of infection in human aspergillosis. IMPORTANCE The phenomena of antibacterial tolerance and persistence, where pathogenic microbes can survive for extended periods in the presence of cidal drug concentrations, have received significant attention in the last decade. Several mechanisms of action have been elucidated, and their relevance for treatment failure in bacterial infections demonstrated. In contrast, our knowledge of antifungal tolerance and, in particular, persistence is still very limited. In this study, we have characterized the response of the prominent fungal pathogen Aspergillus fumigatus to the first-line therapy antifungal voriconazole. We comprehensively show that some isolates display persistence to this fungicidal antifungal and propose various potential mechanisms of action. In addition, using an alternative model of infection, we provide initial evidence to suggest that persistence may cause treatment failure in some individuals. Therefore, we propose that azole persistence is an important factor to consider and further investigate in A. fumigatus.

Outcomes of Salvage Procedures for Failed Total Ankle Arthroplasty

BACKGROUND

The number of total ankle arthroplasty (TAA) procedures increased rapidly in the last years and so have its complications. The main pillars in treating failed TAA are revision total ankle arthroplasty (RTAA), revision total ankle arthrodesis (RAA), or revision tibiotalocalcaneal fusion (RTTC). To evaluate these options, we compared clinical, radiologic, and patient-reported outcomes.

METHODS

A single-center, retrospective review of 111 cases of revision procedures of failed TAA from 2006 to 2020 was performed. Patients undergoing polyethylene exchange and revision of one metallic component were excluded. Demographic data, failure, and survival rates were analyzed. The European Foot and Ankle Society (EFAS) score and radiographic changes in the subtalar joint were evaluated. The average follow-up was 67.89 ± 40.51 months.

RESULTS

One hundred eleven patients underwent removal of TAA. The procedures included 40 revisions of both metallic components, 46 revision total ankle arthrodesis and 25 revision tibiotalocalcaneal fusion. The overall failure rate in the cohort was 5.41% (6/111). The failure rate after RAA was 4.35 times higher than that of RTAA, whereas RTTC did not show failures. RTAA and RTTC lead to a 1-year and 5-year survival rate of 100%. RAA resulted in a 1-year survival rate of 90% and a 5-year survival rate of 85%. The mean EFAS score in the cohort was 12.02 ± 5.83. Analysis of the EFAS score showed that RTTC provided the most reliable pain reduction, and RTAA achieved the best gait pattern. RAA resulted in poorer clinical results. Subtalar joint degeneration occurred significantly less in the RTAA group (P = .01).

CONCLUSION

This retrospective study suggests lower failure rates, increased short-term survival and a better clinical outcomes of revision arthroplasty and tibiotalocalcaneal fusion than ankle arthrodesis. Revision arthroplasty is a promising solution in treating failed total ankle arthroplasty considering lower rate of subsequent adjacent joint degeneration.

LEVEL OF EVIDENCE

Level III, non-randomized observational study.

Extra-short (4-mm) implants placed after regenerative failures in the posterior atrophic mandible: A retrospective study

PURPOSE

To explore whether extra-short (4-mm) implants could be used to rehabilitate sites where regenerative procedures had failed in order to avoid additional bone grafting.

MATERIALS AND METHODS

A retrospective study was conducted among patients who had received extra-short implants after failed regenerative procedures in the posterior atrophic mandible. The research outcomes were complications, implant failure and peri-implant marginal bone loss.

RESULTS

The study population was composed of 35 patients with 103 extra-short implants placed after the failure of different reconstructive approaches. The mean follow-up duration was 41.3 ± 21.4 months post-loading. Two implants failed, leading to a failure rate of 1.94% (95% confidence interval 0.24%-6.84%) and an implant survival rate of 98.06%. The mean amount of marginal bone loss at 5 years post-loading was 0.32 ± 0.32 mm. It was significantly lower in extra-short implants placed in regenerative sites that had previously received a loaded long implant (P = 0.004). Failure of guided bone regeneration before placement of short implants tended to lead to the highest annual rate of marginal bone loss (P = 0.089). The overall rate of biological and prosthetic complications was 6.79% (95% confidence interval 1.94%-11.70%) and 3.88% (95% confidence interval 1.07%-9.65%), respectively. The success rate was 86.4% (95% confidence interval 65.10%-97.10%) after 5 years of loading.

CONCLUSIONS

Within the limitations of this study, extra-short implants seem to be a good clinical option to manage reconstructive surgical failures, reducing surgical invasiveness and rehabilitation time.

Virological failure and adherence to antiretroviral therapy in adolescents and young adults living with human immunodeficiency virus

OBJECTIVE

HIV (human immunodeficiency virus) infection remains a major public health challenge. Infected young people at any age are less likely to adhere to care in a timely manner and to maintain a suppressed VL. This review aims to identify factors associated with virologic failure and adherence to drug therapy in adolescents and young adults (10-24 years) living with HIV.

METHODS

Systematic review using the PubMed and Virtual Health Library databases and including articles published between 2009 and 2021. Data were analysed in six categories: individual factors, pharmacological/therapy-related aspects, factors related to HIV/acquired immunodeficiency syndrome (AIDS) infection, HIV/AIDS stigma, social support and health system/services. The study's protocol was registered on the PROSPERO platform (CRD42020167581).

RESULTS

A total of 19,819 articles were found in the initial search and 31 studies were included in this systematic review. Most studies were carried out on the African continent. Male sex, alcohol use, low education, adverse effects of medication, lack of social support, stigma related to HIV/AIDS, need for transportation to access the health service and forgetfulness were linked to poor adherence to therapy. Good adherence was achieved with sufficient nutrition, good social support, greater confidence in the use of therapy and fewer ART side effects. Low levels of CD4, alcohol use, substance abuse, low education, non-adherence to medication and forgetfulness were linked to virological failure.

CONCLUSION

Individual, social and structural factors constitute barriers to adherence to ART among adolescent and young adults. It is necessary to know the difficulties related to the use of therapy to work out specific strategies that create conditions to improve medication adherence and viral suppression, reducing the levels of virological failure in this population.

Pediatric refractory immune thrombocytopenia: A systematic review

Pediatric immune thrombocytopenia (ITP) is an acquired disorder associated with autoimmune destruction and impairment of platelet production in children. Some children exhibit poor or transient response to ITP-directed treatments and are referred to as having refractory ITP (rITP). There is currently no consensus on the definition of rITP, nor evidence-based treatment guidelines for patients with rITP. After a survey of pediatric ITP experts demonstrated lack of consensus on pediatric rITP, we pursued a systematic review to examine the reported clinical phenotypes and treatment outcomes in pediatric rITP. The search identified 253 relevant manuscripts; following review, 11 studies proposed a definition for pediatric rITP with no consensus amongst them. Most definitions included suboptimal response to medical management, while some outlined specific platelet thresholds to define this suboptimal response. Common attributes identified in this study should be used to propose a comprehensive definition, which will facilitate outcome comparisons of future rITP studies.

Nitrofurantoin failure in males with an uncomplicated urinary tract infection: a primary care observational cohort study

BACKGROUND

Nitrofurantoin is the first-choice antibiotic treatment for uncomplicated urinary tract infections (UTIs) in males according to the Dutch primary care UTI guideline. However, prostate involvement may be undetected and renders this treatment less suitable.

AIM

To compare the nitrofurantoin failure fraction with that found with use of other antibiotics in adult males diagnosed by their GP with an uncomplicated UTI, as well as GP adherence to the Dutch primary care UTI guideline.

DESIGN AND SETTING

Retrospective observational cohort study using routine healthcare data for males seeking care at GP practices participating in the Julius GP Network from 2014 to 2020.

METHOD

Medical records were screened for signs and symptoms of complicated UTIs, antibiotic prescriptions, and referrals. Treatment failure was defined as prescription of a different antibiotic within 30 days after initiation of antibiotic therapy and/or acute hospital referral. The effects of age and comorbidities on failure were assessed using multivariable logistic regression.

RESULTS

Most UTI episodes in males were uncomplicated (n = 6805/10 055 episodes, 68%). Nitrofurantoin  was prescribed in 3788 (56%) of uncomplicated UTIs, followed by ciprofloxacin (n = 1887,  28%), amoxicillin/clavulanic acid (n = 470,  7%), and trimethoprim/sulfamethoxazole (n = 285, 4%). Antibiotic failure occurred in  25% (95% confidence interval [CI] = 23 to 26), 10% (95% CI = 9 to 12), 20% (95% CI = 16 to 24), and 14% (95% CI = 10 to 19) of episodes, respectively. The nitrofurantoin failure fraction increased with age. Comorbidities, adjusted for age, were not associated with nitrofurantoin failure.

CONCLUSION

Nitrofurantoin failure was common in males with uncomplicated UTI and increased with age.

Ventilator-Associated Pneumonia in COVID-19 Patients Admitted in Intensive Care Units: Relapse, Therapeutic Failure and Attributable Mortality-A Multicentric Observational Study from the OutcomeRea Network

Introduction: Ventilator-associated pneumonia (VAP) incidence is high among critically ill COVID-19 patients. Its attributable mortality remains underestimated, especially for unresolved episodes. Indeed, the impact of therapeutic failures and the determinants that potentially affect mortality are poorly evaluated. We assessed the prognosis of VAP in severe COVID-19 cases and the impact of relapse, superinfection, and treatment failure on 60-day mortality. Methods: We evaluated the incidence of VAP in a multicenter prospective cohort that included adult patients with severe COVID-19, who required mechanical ventilation for ≥48 h between March 2020 and June 2021. We investigated the risk factors for 30-day and 60-day mortality, and the factors associated with relapse, superinfection, and treatment failure. Results: Among 1424 patients admitted to eleven centers, 540 were invasively ventilated for 48 h or more, and 231 had VAP episodes, which were caused by Enterobacterales (49.8%), P. aeruginosa (24.8%), and S. aureus (22%). The VAP incidence rate was 45.6/1000 ventilator days, and the cumulative incidence at Day 30 was 60%. VAP increased the duration of mechanical ventilation without modifying the crude 60-day death rate (47.6% vs. 44.7% without VAP) and resulted in a 36% increase in death hazard. Late-onset pneumonia represented 179 episodes (78.2%) and was responsible for a 56% increase in death hazard. The cumulative incidence rates of relapse and superinfection were 45% and 39.5%, respectively, but did not impact death hazard. Superinfection was more frequently related to ECMO and first episode of VAP caused by non-fermenting bacteria. The risk factors for treatment failure were an absence of highly susceptible microorganisms and vasopressor need at VAP onset. Conclusions: The incidence of VAP, mainly late-onset episodes, is high in COVID-19 patients and associated with an increased risk of death, similar to that observed in other mechanically ventilated patients. The high rate of VAP due to difficult-to-treat microorganisms, pharmacokinetic alterations induced by renal replacement therapy, shock, and ECMO likely explains the high cumulative risk of relapse, superinfection, and treatment failure.

What ultimately matters in root canal treatment success and tooth preservation: A 25-year cohort study

AIM

There are currently no prospective studies evaluating the long-term outcomes of non-surgical root canal treatments beyond 5 years, both in terms of treatment success and tooth preservation, and identifying factors predictive of treatment outcome. The aim of the present work was therefore to fill this gap by assessing these outcomes over time and identifying predictive variables based on systematic data collection over a 25-year period.

METHODOLOGY

Data concerning the treatments (N = 2500) were systematically collected since 1990. Information was recorded among clinical, technical, radiographic and patient-related characteristics, i.e., approximately 150 variables for each treatment. The data were analysed regarding both treatment success and tooth preservation by multivariable Cox proportional hazards model, and survival curves were generated. The statistical significance level was set at 0.0125.

RESULTS

In total, 56.4% of the treatments could be followed over time (0-25 years, mean = 6.5 years, median = 5 years). Survival probability decreased almost linearly for treatment success, with about 85% after 5 years and 60% after 20 years, and for tooth preservation, with about 90% at 5 years and 50% at 20 years. The variables significantly associated with treatment failure were: pre-operative pain (Hazard Ratio-HR = 1.56 [95% CI 1.23-1.97]), persistent pain (HR = 2.63 [95% CI 1.44-4.80]), good operator rating of treatment prognosis (HR = 0.46 [95% CI 0.36-0.58]), size of periapical bone radiolucency (HR = 1.88 [95% CI 1.67-2.11]), and tooth type (p = .0006). For tooth extraction, they were: combined endodontic-periodontal lesion (HR = 3.37 [95% CI 1.88-6.05]), pre-existing complication before treatment (HR = 1.67 [95% CI 1.26-2.21]), good operator rating of treatment prognosis (HR = 0.45 [95% CI 0.33-0.60]), clinical failure of root canal treatment (HR = 2.78 [95% CI 1.98-3.89]) and tooth type (p = .0012).

CONCLUSION

Root canal treatment success and tooth preservation on the arch are not static outcomes, but evolve with time. Among a substantial set of potential predictors, only a small proportion was significantly predictive of treatment success and tooth preservation, most of them being disease and patient characteristics, and not technical aspects, except pre-existing complications. These observations challenge the importance frequently given to byzantine considerations related to the numerous technical details of endodontic procedures, as opposed to general concepts of good clinical practice.

Risk of Treatment Failure for Prosthetic Joint Infections: Retrospective Chart Review in an Outpatient Parenteral Antimicrobial Therapy Program

Background

Prosthetic joint infections (PJIs) are a major complication of total joint replacement surgeries. Treatment includes surgical intervention with prolonged courses of IV antibiotics in outpatient parenteral antimicrobial therapy (OPAT) programs. The risk of PJI treatment failure is high and may be associated with various clinical factors.

Objectives

To determine the rate of PJI treatment failure and to identify potential risk factors for failure in patients admitted to an OPAT program.

Methods

A retrospective chart review was conducted for adult patients with PJI admitted to an OPAT program between July 1, 2013, and July 1, 2019. Treatment courses were deemed to have failed according to predetermined criteria. χ² tests and multiple linear regression were used to examine associations of comorbidities, pathogens, and antimicrobial regimens with treatment failure.

Results

In total, 100 patients associated with 137 PJI treatment courses in the OPAT program were included. Of these, 28 patients accounted for 65 of the treatment courses. Methicillin-susceptible Staphylococcus aureus was the most frequently isolated pathogen (31/137 or 22.6% of treatment courses). Patient comorbidities included body mass index of at least 30 kg/m² (58% of patients) and diabetes (41% of patients). The overall rate of treatment failure was 56.2% (77/137 treatment courses). Selected risk factors associated with treatment failure or success were diabetes (50.9% versus 29.8%; odds ratio [OR] 4.03, 95% confidence interval [CI] 1.38-12.88, p = 0.013) and depression (32.1% versus 14.9%; OR 5.02, 95% CI 1.30-22.89, p = 0.025).

Conclusions

The overall rate of PJI treatment failure in the study population was high. Patients with diabetes and depression experienced higher incidences of failure. Future investigations of comprehensive PJI management should be considered to ensure successful treatment and to minimize excessive use of health care resources.