Tularemia Clinical Manifestations, Antimicrobial Treatment, and Outcomes: An Analysis of US Surveillance Data, 2006-2021.

BACKGROUND: Tularemia, a potentially fatal zoonosis caused by Francisella tularensis, has been reported from nearly all US states. Information on relative effectiveness of various antimicrobials for treatment of tularemia is limited, particularly for newer classes such as fluoroquinolones. METHODS: Data on clinical manifestations, antimicrobial treatment, and illness outcome of patients with tularemia are provided voluntarily through case report forms to the US Centers for Disease Control and Prevention by state and local health departments. We summarized available demographic and clinical information submitted during 2006-2021 and evaluated survival according to antimicrobial treatment. We grouped administered antimicrobials into those considered effective for treatment of tularemia (aminoglycosides, fluoroquinolones, and tetracyclines) and those with limited efficacy. Logistic regression models with a bias-reduced estimation method were used to evaluate associations between antimicrobial treatment and survival. RESULTS: Case report forms were available for 1163 US patients with tularemia. Francisella tularensis was cultured from a clinical specimen (eg, blood, pleural fluid) in approximately half of patients (592; 50.9%). Nearly three-quarters (853; 73.3%) of patients were treated with a high-efficacy antimicrobial. A total of 27 patients (2.3%) died. After controlling for positive culture as a proxy for illness severity, use of aminoglycosides, fluoroquinolones, and tetracyclines was independently associated with increased odds of survival. CONCLUSIONS: Most US patients with tularemia received high-efficacy antimicrobials; their use was associated with improved odds of survival regardless of antimicrobial class. Our findings provide supportive evidence that fluoroquinolones are an effective option for treatment of tularemia.

Lowering mortality risk in CR-HvKP infection in intestinal immunohistological and microbiota restoration.

Gut damage during carbapenem-resistant and hypervirulent Klebsiella pneumoniae (CR-HvKP) infection is associated with a death risk. Understanding the mechanisms by which CR-HvKP causes intestinal damage and gut microbiota alteration, and the impact on immunity, is crucial for developing therapeutic strategies. This study investigated if gastrointestinal tract damage and disruption of gut microbiota induced by CR-HvKP infection undermined host immunity and facilitated multi-organ invasion of CR-HvKP; whether the therapeutic value of the rifampicin (RIF) and zidovudine (ZDV) combination was attributed to their ability to repair damages and restore host immunity was determined. A sepsis model was utilized to assess the intestinal pathological changes. Metagenomic analysis was performed to characterize the alteration of gut microbiota. The effects of the RIF and ZDV on suppressing inflammatory responses and improving immune functions and gut microbiota were evaluated by immunopathological and transcriptomic analyses. Rapid colonic damage occurred upon activation of the inflammation signaling pathways during lethal infections. Gut inflammation compromised host innate immunity and led to a significant decrease in probiotics abundance, including Bifidobacterium and Lactobacillus. Treatment with combination drugs significantly attenuated the inflammatory response, up-regulated immune cell differentiation signaling pathways, and promoted the abundance of Bifidobacterium (33.40 %). Consistently, supplementation of Bifidobacterium alone delayed the death in sepsis model. Gut inflammation and disrupted microbiota are key disease features of CR-HvKP infection but can be reversed by the RIF and ZDV drug combination. The finding that these drugs can restore host immunity through multiple mechanisms is novel and deserves further investigation of their clinical application potential.

Lack of microbiological awareness on the ward as a key factor for inappropriate use of anti-infectives: results of a point prevalence study and user satisfaction survey in a large university hospital in Austria.

PURPOSE: Although diagnostic stewardship issues in clinical microbiology harbor an optimization potential for anti-infective consumption, they are only marginally addressed in antimicrobial stewardship (AMS) programs. As part of an AMS point prevalence (PPS) survey we therefore aimed to gain a more dynamic view on the microbiological awareness within therapeutic regimens. By examining whether initial microbiological sampling was performed and in which way microbiological results were incorporated into further treatment considerations we sought to find out to what extent these points determine the appropriateness of treatment regimens. METHODS: PPS was performed at the University Hospital Salzburg (1524 beds) in May 2021. Relevant data was determined from the patient charts and the appropriateness of anti-infective use was assessed using predefined quality indicators. Six months after the PPS, a questionnaire was administered to clinicians to obtain information on the use of microbiological findings and their relevance in the clinic. RESULTS: Lack of microbiological awareness in the clinical setting proved to be the key reason for an overall inadequate use of anti-infectives (35.4% of cases rated as inadequate), ahead of the aspects of dose (24.1%), empirical therapy (20.3%) and treatment duration (20.2%). This was particularly the case for broad-acting agents and was most evident in urinary tract infections, skin and soft tissue infections, and pneumonia. The results of the questionnaire indicate a discrepancy between the physicians surveyed and the routine clinical setting. CONCLUSION: A high potential in improving the use of anti-infectives in hospitals seems to lie in a strong emphasis on microbiological diagnostic stewardship measures.

Fluoroquinolone resistance and clinical characteristics of acute bacterial prostatitis in Japan: A multicenter study by the Japanese research group for urinary tract infection.

OBJECTIVE: This multicenter study aimed to analyze the risk factors for fluoroquinolone (FQ) resistance and to clarify the clinical characteristics of acute bacterial prostatitis (ABP) in Japan. METHODS: A total of 124 patients clinically diagnosed with ABP at 13 medical institutions participating in the Japanese Research Group for Urinary Tract Infection between January and December 2017 were retrospectively reviewed. RESULTS: Of the 124 patients included in this study, 37 were outpatients, and 87 were inpatients. The main underlying medical conditions before the onset of ABP were severe dysuria, urinary retention, transurethral manipulation, indwelling urinary catheter, and transrectal prostate biopsy (TRBx). The main symptoms were fever (≥37.5 °C), prostate tenderness, dysuria, micturition pain, urinary retention, and macrohematuria. Bacteremia was observed in 14 patients. Prostatic abscess was observed in three patients. Escherichia coli was the predominant organism, accounting for 48 % (51/106). FQ-resistant E. coli was detected in 33 % (17/51), and extended-spectrum beta-lactamase-producing E. coli in 12 % (6/51). TRBx (odds ratio [OR] = 48.60, 95 % confidence interval [CI]: 5.49-430.00, p < 0.001) and inpatient status (OR = 29.00, 95 % CI: 1.95-430.00, p = 0.014) were risk factors for the detection of FQ-resistant bacteria. CONCLUSIONS: The detection rate of FQ-resistant bacteria was significantly higher with TRBx ABP and inpatient status. These findings have important implications for the management of ABP and antimicrobial treatment, especially for TRBx ABP, which should be considered a separate category.

Home nursing and self-administered outpatient parenteral antimicrobial treatment: a comparison of demographics and outcomes from a large regional hospital in Queensland, Australia.

BACKGROUND: Outpatient parenteral antimicrobial treatment (OPAT) is a safe and effective therapy used in several settings across Australia. As OPAT services expand their inclusion criteria to include complex patient populations, there is an increased need for selecting appropriate patients to receive either healthcare-administered OPAT (H-OPAT) or self-administered OPAT (S-OPAT). AIMS: To describe patient demographics, diagnosis, microbiology and outcomes of patients treated by H-OPAT and S-OPAT within the Sunshine Coast Hospital and Health Service, Australia. METHODS: Data on demographics, diagnoses, treatment and outcomes on all patients treated by H-OPAT and S-OPAT from March 2017 to December 2019 were collected retrospectively. RESULTS: One hundred and sixty-five patients (62.26%) were enrolled in H-OPAT and 100 patients (37.74%) in S-OPAT. S-OPAT patients were significantly younger. H-OPAT patients were more comorbid. Bone and joint infections were the most treated infections and were more likely to be treated by S-OPAT. There was no difference in treatment duration, cure and complication rates between S-OPAT and H-OPAT. Longer duration of therapy was associated with more complications. Treatment failure was associated with infections due to multiple organisms, number of comorbidities and treatment of surgical site, skin and soft tissue infections. CONCLUSIONS: There were significant differences in demographics between H-OPAT and S-OPAT without any difference in outcomes. Overall failure and complication rates were low. Higher rates of treatment failure were predicted by the diagnosis, number of comorbidities and number of organisms treated.

In vitro effects of phytogenic feed additive on Piscirickettsia salmonis growth and biofilm formation.

Piscirickettsiosis is the main cause of mortality in salmonids of commercial importance in Chile, which is caused by Piscirickettsia salmonis, a Gram-negative, γ-proteobacteria that can produce biofilm as one of its virulence factors. The Chilean salmon industry uses large amounts of antibiotics to control piscirickettsiosis outbreaks, which has raised concern about its environmental impact and the potential to induce antibiotic resistance. Thus, the use of phytogenic feed additives (PFA) with antibacterial activity emerges as an interesting alternative to antimicrobials. Our study describes the antimicrobial action of an Andrographis paniculate-extracted PFA on P. salmonis planktonic growth and biofilm formation. We observed complete inhibition of planktonic and biofilm growth with 500 and 400 µg/mL of PFA for P. salmonis LF-89 and EM-90-like strains, respectively. Furthermore, 500 µg/mL of PFA was bactericidal for both evaluated bacterial strains. Sub-inhibitory doses of PFA increase the transcript levels of stress (groEL), biofilm (pslD), and efflux pump (acrB) genes for both P. salmonis strains in planktonic and sessile conditions. In conclusion, our results demonstrate the antibacterial effect of PFA against P. salmonis in vitro, highlighting the potential of PFA as an alternative to control Piscirickettsiosis.

Antibiofilm Activity of Combretum micranthum G. Don Catechin-Sugar Phytocomplex on Pseudomonas aeruginosa.

Clinicians often have to face infections caused by microorganisms that are difficult to eradicate due to their resistance and/or tolerance to antimicrobials. Among these pathogens, Pseudomonas aeruginosa causes chronic infections due to its ability to form biofilms on medical devices, skin wounds, ulcers and the lungs of patients with Cystic Fibrosis. In this scenario, the plant world represents an important reservoir of natural compounds with antimicrobial and/or antibiofilm properties. In this study, an extract from the leaves of Combretum micranthum G. Don, named Cm4-p, which was previously investigated for its antimicrobial activities, was assayed for its capacity to inhibit biofilm formation and/or to eradicate formed biofilms. The model strain P. aeruginosa PAO1 and its isogenic biofilm hyperproducer derivative B13 were treated with Cm4-p. Preliminary IR, UV-vis, NMR, and mass spectrometry analyses showed that the extract was mainly composed of catechins bearing different sugar moieties. The phytocomplex (3 g/L) inhibited the biofilm formation of both the PAO1 and B13 strains in a significant manner. In light of the obtained results, Cm4-p deserves deeper investigations of its potential in the antimicrobial field.

Antimicrobial treatment in invasive infections caused by Gordonia bronchialis: systematic review.

Background: Corynebacterium, Nocardia, Rhodococcus, Mycobacterium, as well as Gordonia genera belongs to the genus Gordonia, Actinomycetia class. Gordonia bronchialis is a nitrate-reducing, urease-producing, non-motile, force aerobe with a rod-like figure that is known to arrangement into sessile, cord-like groups. This systematic review aimed to establish whether and what invasive infections in humans were caused by Gordonia bronchialis, and to evaluate outcomes of administered antibiotic treatment. Methods: We have registered this systematic review in PROSPERO database of systematic reviews and meta-analyses with the number CRD42022369974. Results: A total of 24 publications were included (22 case reports and two case series) with 28 individual cases. The oldest patients had 92 years, and the youngest patients had 13 years. Clinical signs of infection were present in six patients (21%). All isolates were susceptible to ciprofloxacin, imipenem, and amikacin. Vancomycin was the most frequently used antibiotic with nine cases followed by ciprofloxacin, ceftriaxone, and amoxicillin/clavulanic acid. Conclusion: Although there are no standardized recommendations to date, successful treatment with a favorable outcome has most often been carried out with fluoroquinolones, vancomycin with or without aminoglycosides, as well as carbapenems.

Clinical characteristic, management, and outcomes of cervical spinal brucellosis: a retrospective cohort study over 1-year postoperative follow-up.

BACKGROUND: The incidence of cervical spinal brucellosis is low, only a few case reports have been published, and case series are not widely reported in the medical literature. Therefore, clinical features, management, and outcomes of cervical spinal brucellosis are relatively unknown. In this series, the authors report 15 cases of patients with cervical spinal brucellosis, including clinical characteristic, imaging findings, management plans, the institution's experience, and outcomes at 1 year postoperatively. METHODS: The study reviewed the clinical and radiographic records of 15 patients who received antimicrobial pharmacotherapy, and anterior cervical debridement and fusion for cervical spinal brucellosis. The data collected included patient demographic characteristics, spinal level affected, abscess, neurology, pathological reports, duration and type of antimicrobial regimens, details of orthopedic management, and complications incurred during the procedure. RESULTS: Neck pain (100%) and limb paralysis (86.7%) were the most common clinical presentations, and the disease had a rapid progression. The C6-7 segment was the most commonly affected segment, followed by C4-5 and C5-6. Imaging commonly revealed epidural or paravertebral abscesses (80%). There was a significant improvement in the VAS, JOA, and NDI scores three months after surgery, and the scores continued to improve until the final follow-up. There was a statistically significant difference between the pre- and postoperative scores (P < 0.05). The ESR and CRP levels returned to normal within three months postoperatively, being 7.7 ± 4.5 mm/h and 7.55 ± 3.48 mg/L, respectively. There were statistically significant differences between the pre- and postoperative levels (P < 0.05). The positive rate of bacterial culture testing of pus or lesion tissues was only 40%, but blood cultures revealed an even lower positivity rate (33.3%). The average antimicrobial pharmacotherapy regimen duration was 6.1 ± 1.9 months. All patients achieved intervertebral bone fusion within 8 months (4.8 ± 1.4 months) after surgery and were cured with non-recurrence. CONCLUSIONS: Spinal brucellosis rarely affects the cervical region, but its impact is more dangerous due to potential complications such as paraplegia or tetraplegia arising from epidural abscesses that compress the spinal cord. Surgical debridement, along with essential antimicrobial therapy, is an effective strategy and can lead to satisfactory prognosis in managing cervical spinal brucellosis.

Evaluation of the Economic Impact of Streptococcus suis-Associated Disease.

The economic impact of Streptococcus suis-associated disease at farm level is well known by the producers, but the cost in a region or a country is more difficult to evaluate due to the lack of a centralized data system, the different incidences, and the control measures applied by each producer. In this chapter, we describe a method based on the information gathered through interviews with veterinary practitioners. A comprehensive questionnaire created specifically for the disease can help to conduct the interviews. The questions include information about the proportions of farms, batches and animals clinically affected, mortality, metaphylactic and therapeutic treatments, use of vaccines, and proportion of cases that are diagnosed at the laboratory. As the questionnaire is quite complex, the best option to obtain the data is send the questionnaire to the selected veterinarians to allow them to collect some data and make an interview with them some days later. The information allows to estimate the costs due to mortality, antimicrobial treatments, the use of autogenous vaccines, and analyses performed. Initially they are calculated per animal in each affected production phase, and later it can be extrapolated to estimate the annual cost per affected production unit and per country. The model does not consider indirect costs such as the cost as a zoonosis, the revenues forgone, or an increase of labor.

Infectious Scleritis - Clinical Characteristics, Causative Factors, and Treatment Outcomes in an Indian Population.

PURPOSE: To study the clinical features, causative factors and treatment outcomes in patients with infectious scleritis seen in India. METHODS: A retrospective study of all patients examined at a tertiary care center between August 2012 and March 2021. RESULTS: Forty-five patients (45 eyes; mean age 52.7 ± 17.5 years) were included in the study. The mean duration of symptoms was 3.1 ± 4.4 months. Inciting factors were found in 53.3% (injury: 33.3%; ocular surgery: 20.0%). The scleritis was predominantly anterior (97.8%), with multiple lesions in 40.0%, a solitary lesion in 31.1%, and diffuse in 28.9%. Associated features included uveitis (51.1%), keratitis (37.8%), hypopyon (15.6%), and endophthalmitis (6.7%). Causative organisms included bacteria (53.3%), fungi (35.6%), and presumed herpes virus (11.1%). All patients were treated with antimicrobial agents along with systemic corticosteroids where indicated. Surgical treatment included scleral debridement (37.8%), patch grafts (4.4%), and penetrating keratoplasty (2.2%). Complete resolution of scleritis was seen in 86.7%, with a mean duration of therapy of 2.9 ± 2.5 months. The mean follow-up was 8.3 ± 14.3 months. 51.1% of patients lost functional vision (<6/60). Causes of decreased vision included corneal scar, cataract, macular scar, glaucomatous optic atrophy, and phthisis bulbi. On bivariate analysis, poor visual acuity at presentation was associated with a worse visual outcome (p = 0.02). Other risk factors included necrotizing scleritis, multifocal scleritis, the presence of keratitis and uveitis. CONCLUSION: In our study, infectious scleritis resulted from bacterial and fungal infections. The scleritis resolved in most subjects, however, vision loss was frequent due to infection-related complications.

Microbiological Profiles of Patients with Spondylodiscitis.

Spondylodiscitis is a severe spinal infection that requires an effective antibiotic treatment. Therefore, we sought to analyse the causative pathogens from intraoperative specimen in patients with spondylodiscitis and a need for surgery. To this end, we performed a retrospective study of all patients with spondylodiscitis and a need for operative treatment admitted to our hospital between January 2020 and December 2022. A total of 114 cases with spondylodiscitis were identified. A total of 120 different pathogens were detected. Overall, 76.7% of those microorganisms were Gram-positive bacteria. The most common causative pathogen was Staphylococcus aureus (n = 32; 26.6%), followed by coagulase-negative staphylococci (n = 28; 23.4%), of which Staphylococcus epidermidis (n = 18; 15%) was the most frequently detected, as well as enterococci (n = 10; 8.4%) and Streptococcus spp. (n = 11; 9.2%). Moreover, 19.1% (n = 22) and 3.4% (n = 4) of all detected isolates were Gram-negative pathogens or fungi, respectively. Overall, 42.8% of all coagulase-negative staphylococci were oxacillin-resistant, while none of them were vancomycin-resistant. In summary, 50% of the pathogens could be identified as staphylococci. The results of our study highlight the important burden of oxacillin-resistant Gram-positive bacteria as an aetiological cause of spondylodiscitis, providing a relevant finding for antimicrobial stewardship programmes.

Meningococcal meningitis in Spain in the Horizon 2030: A position paper.

Meningococcal meningitis (MM) and invasive meningococcal disease remain a major public health problem that generates enormous public alarm. It is caused by Neisseria meningitidis, a Gram-negative diplococcus with an enormous capacity for acute and rapidly progressive disease, both episodic and epidemic in nature, with early diagnosis and treatment playing a major role. It occurs at any age, but is most common in children under 5 years of age followed by adolescents. Although most cases occur in healthy people, the incidence is higher in certain risk groups. Despite advances in reducing the incidence, it is estimated that in 2017 there were around 5 million new cases of MM worldwide, causing approximately 290,000 deaths and a cumulative loss of about 20,000,000 years of healthy life. In Spain, in the 2021/22 season, 108 microbiologically confirmed cases of MM were reported, corresponding to an incidence rate of 0.23 cases per 100,000 inhabitants. This is a curable and, above all, vaccine-preventable disease, for which the World Health Organisation has drawn up a roadmap with the aim of reducing mortality and sequelae by 2030. For all these reasons, the Illustrious Official College of Physicians of Madrid (ICOMEM) and the Medical Associations of 8 other provinces of Spain, have prepared this opinion document on the situation of MM in Spain and the resources and preparation for the fight against it in our country. The COVID-19 and Emerging Pathogens Committee of ICOMEM has invited experts in the field to participate in the elaboration of this document.

Association between respiratory disease pathogens in calves near feedlot arrival with treatment for bovine respiratory disease and subsequent antimicrobial resistance status.

Introduction: This study assessed the risk of first treatment for bovine respiratory disease (BRD) given detection of nasopharyngeal bacteria (Mannheimia haemolytica, Pasteurella multocida, and Histophilus somni) and corresponding likelihood of antimicrobial susceptibility (C/S) at two time points during the early feeding period. Relationships between C/S results and later treatment for BRD were evaluated at both the calf-level and pen-level. The association between calf-level and pen-level C/S findings during the early feeding period and subsequent C/S results at BRD treatment were also reported. Methods: Auction-sourced, recently-weaned beef calves (n = 1,599 steers) were placed in adjacent feedlot pens (8 × 100 calves) in two subsequent years. Deep nasopharyngeal (DNP) swabs were collected from all calves at time of arrival processing (1DOF) and before metaphylaxis administration with either tulathromycin or oxytetracycline, 12 days later (13DOF), and at the time of first treatment for BRD. All samples were tested for C/S. Results: Several pen-level and individual calf-level C/S measures of interest were associated with future treatment for BRD and C/S at the time of treatment. The median DOF for first BRD treatment was 24 days following tulathromycin metaphylaxis and 11 days following oxytetracycline. Overall, sampling at 13DOF resulted in the best fit for more models of subsequent treatment for BRD and C/S results at BRD treatment than for sampling at arrival. In individual calves, recovery of M. haemolytica, P. multocida, or H. somni at 13DOF was associated with subsequent treatment for BRD within 45DOF. Pen-level prevalence of Pasteurellacea bacteria with tetracycline or macrolide resistance at arrival and 13DOF were associated with detection of bacteria with antimicrobial resistance (AMR) at BRD treatment, as were individual calf results at 13DOF. Discussion: These findings suggest that the bacteria and AMR outcomes recovered from cattle near two weeks on feed can inform the prediction of future BRD risk and concurrent antimicrobial susceptibility results at time of first BRD treatment. Notably, the associations between pen-level C/S results from previous testing and corresponding findings in calves with BRD from the same pen suggested potential testing strategies to inform antimicrobial use protocols for feedlot cattle.

Antimicrobial Treatment Challenges in the Management of Infective Spondylodiscitis Associated with Hemodialysis: A Comprehensive Review of Literature and Case Series Analysis.

Infective spondylodiscitis (ISD), the infection of vertebral bodies and surrounding tissues, is a rare complication with major impact on the long-term survival of hemodialysis (HD) patients. Although the most frequent etiology is staphylococcal, identifying these pathogens in blood cultures and biopsy cultures is often difficult. This paper aims to present suitable antibiotic combinations for the treatment of these patients, which is usually challenging in the case of an unidentified pathogen. We presented the therapies applied for 13 HD patients and 19 patients without chronic kidney disease (CKD), diagnosed with ISD between 2013 and 2023 in Bihor County. The percentage of positive blood cultures was low in both groups (30.78% HD vs. 15.78% non-HD). The average length of antibiotic therapy was 5.15 weeks in HD patients and 6.29 weeks in non-HD patients. The use of Carbapenem alone (e.g., Meropenem) for an average of 19.6 days for patients in HD when the pathogen was not identified has proven to be efficient in most cases, similarly to using Vancomycin and Fluoroquinolone/Cephalosporines in combination. Regarding the non-CKD patients, the use of Clindamycin in various combinations for an average of 30.3 days has proven to be efficient in more than 90% of cases of ISD with a nonidentified pathogen. Within 2 years after ISD was diagnosed, 12 of the 13 HD patients passed away, mainly due to cardiovascular causes. Unfortunately, there are no guidelines in the literature concerning the empiric treatment of ISD in the particular case of HD patients. Upon checking the literature on PubMed and Google Scholar, only 10 studies provided relevant data regarding ISD treatment for HD patients. More data about the treatment and evolution of these patients is needed in order to elaborate a truly relevant metanalysis.

A Case Report of Black Hairy Tongue (Melanotrichia Linguae or Lingua Pilosa Nigra).

Black hairy tongue is a benign condition that can be associated with several varying causes. Its etiology is often linked with fungal infection and adverse reactions to various drugs. We present a case of an adult patient who developed a black hairy tongue while on ceftriaxone and pantoprazole for 10 days. The fungus on his tongue was not identified as the causative agent, and recovery was achieved by changing his medications. Ceftriaxone was replaced with trimethoprim/sulfamethoxazole 5 mg/kg intravenous, and pantoprazole was fully stopped. The black lesion on the tongue was observed to regress over several days. Clinicians should be aware of this particular side effect of certain antibiotics.

Benign Tuberculous Constrictive Pericarditis: A Case of Complete Resolution with Empirical Antimicrobial Treatment.

Tuberculous (TB) pericarditis is a well-known manifestation of tuberculosis, particularly in endemic regions. The progression to constrictive pericarditis, while under anti-tuberculosis treatment, is reported to be as high as 30%. This report presents a case of a 56-year-old female patient who complained of cough, pleuritic chest pain, night sweats, and fever, followed by orthopnea, dyspnea, and peripheral edema. Transthoracic echocardiography revealed the early stages of constrictive pericarditis and a small pericardial effusion. Chest computed tomography (CT) showed a thickened pericardium, small pericardial and pleural effusions, and multiple mediastinal lymphadenopathies. Due to a high suspicion of tuberculous pericarditis, the patient was administered empirical anti-TB treatment. A follow-up after two months showed complete resolution of symptoms and echocardiographic findings. Empirical antimicrobial treatment in endemic areas is a well-established strategy for managing tuberculous infection and proved successful in this patient. The early presentation and the significant improvement in signs and symptoms following the medical anti-TB regimen, without the need for pericardiectomy, were unique aspects of this case.

Pharmacodynamics of zoliflodacin plus doxycycline combination therapy against Neisseria gonorrhoeae in a gonococcal hollow-fiber infection model.

Antimicrobial resistance in the sexually transmitted bacterium Neisseria gonorrhoeae is compromising the management and control of gonorrhea globally. Optimized use and enhanced stewardship of current antimicrobials and development of novel antimicrobials are imperative. The first in class zoliflodacin (spiropyrimidinetrione, DNA Gyrase B inhibitor) is a promising novel antimicrobial in late-stage clinical development for gonorrhea treatment, i.e., the phase III randomized controlled clinical trial (ClinicalTrials.gov Identifier: NCT03959527) was recently finalized, and zoliflodacin showed non-inferiority compared to the recommended ceftriaxone plus azithromycin dual therapy. Doxycycline, the first-line treatment for chlamydia and empiric treatment for non-gonococcal urethritis, will be frequently given together with zoliflodacin because gonorrhea and chlamydia coinfections are common. In a previous static in vitro study, it was indicated that doxycycline/tetracycline inhibited the gonococcal killing of zoliflodacin in 6-h time-kill curve analysis. In this study, our dynamic in vitro hollow-fiber infection model (HFIM) was used to investigate combination therapies with zoliflodacin and doxycycline. Dose-range experiments using the three gonococcal strains WHO F (susceptible to relevant therapeutic antimicrobials), WHO X (extensively drug-resistant, including ceftriaxone-resistant; zoliflodacin-susceptible), and SE600/18 (zoliflodacin-susceptible strain with GyrB S467N substitution) were conducted simulating combination therapy with a single oral dose of zoliflodacin 0.5-4 g combined with a doxycycline daily oral dose of 200 mg administered as 100 mg twice a day, for 7 days (standard dose for chlamydia treatment). Comparing combination therapy of zoliflodacin (0.5-4 g single dose) plus doxycycline (200 mg divided into 100 mg twice a day orally, for 7 days) to zoliflodacin monotherapy (0.5-4 g single dose) showed that combination therapy was slightly more effective than monotherapy in the killing of N. gonorrhoeae and suppressing emergence of zoliflodacin resistance. Accordingly, WHO F was eradicated by only 0.5 g single dose of zoliflodacin in combination with doxycycline, and WHO X and SE600/18 were both eradicated by a 2 g single dose of zoliflodacin in combination with doxycycline; no zoliflodacin-resistant populations occurred during the 7-day experiment when using this zoliflodacin dose. When using suboptimal (0.5-1 g) zoliflodacin doses together with doxycycline, gonococcal mutants with increased zoliflodacin MICs, due to GyrB D429N and the novel GyrB T472P, emerged, but both the mutants had an impaired biofitness. The present study shows the high efficacy of zoliflodacin plus doxycycline combination therapy using a dynamic HFIM that more accurately and comprehensively simulate gonococcal infection and their treatment, i.e., compared to static in vitro models, such as short-time checkerboard experiments or time-kill curve analysis. Based on our dynamic in vitro HFIM work, zoliflodacin plus doxycycline for the treatment of both gonorrhea and chlamydia can be an effective combination.