Culture Fluid Research Articles

Effect of the growth-stimulating bacterium <i>Pseudomonas protegens</i> DA1.2 and its metabolites on damage to rapeseed by soil residues of metsulfuron-methyl

The biochemical processes mediating the positive effect of bacteria on plants experiencing herbicidal stress were investigated. For this purpose the effect of the Pseudomonas protegens DA1.2 bacterial strain, low molecular weight (5 kDa) and high molecular weight (5 kDa) fractions of its culture fluid (CF) on the activity of acetolactate synthase (ALS) and the antioxidant status of rapeseed (Brassica napus L.) of the Kupol variety grown under artificial lighting in methsulfuron-methyl contaminated soil was evaluated. Strain P. protegens DA1.2 and its metabolites contributed to an increase in the mass of rapeseed shoots by 21–68%, reduced the inhibition of the ALS enzyme by 11–24% and mitigated the manifestations of oxidative stress. The protective effect of the treatments decreased in a row: CF with living bacterial cells-low molecular weight fraction of CF-high molecular weight fraction of CF. An increase in the activity of superoxide dismutase by 51–94% and glutathione reductase by 17–20% in plants treated with bacteria or their metabolites indicated the possible participation of these antioxidant enzymes in reducing the phytotoxicity of metsulfuron-methyl soil residues for rapeseed plants.

Diversity of extracellular vesicles derived from calli, cell culture and apoplastic fluid of tobacco

In recent years, there has been a growing interest in plant extracellular vesicles (pEVs) due to their immense potential for medical applications, particularly as carriers for drug delivery. To use the benefits of pEVs in the future, it is necessary to identify methods that facilitate their production in sufficient quantities while maintaining high quality. In this study, a comparative analysis of yields of tobacco pEV derived from apoplastic fluid, sterile calli, and suspension cultures, was performed to identify the most suitable plant material for vesicle isolation. Subsequent experiments focused on assessing the efficiency of small interfering RNA (siRNA) loading into callus-derived vesicles, employing various methods such as sonication, incubation, incubation supplemented with saponin, lipofection, and electroporation. Differences in loading efficiency among vesicles derived from apoplastic fluid, calli, and suspension cultures were observed. Moreover, our investigation extended to the presence of tobacco secondary metabolites, specifically anabasine and nicotine, within vesicles originating from three distinct tobacco sources. The outcomes of our study highlight variations not only in vesicle yields based on their source but also in their loadability and the presence of nicotine and anabasine. These findings contribute valuable insights into optimizing the production and application of pEVs for future medicinal purposes.

The effect of long-term storage on the viability and properties of Alternaria alternata, Bipolaris sorokiniana and Fusarium solani strains of the Phytopathogenic Microorganisms State Collection of ARRIP

Relevance. Under conditions of prolonged storage of fungi on a nutrient agar medium, their pathogenic properties are gradually lost. Preservation of collection material with unchanged pathogenic properties is necessary for correct research, including the development of biological protection methods, monitoring of pathogen development dynamics, assessment of their virulence and aggressiveness, choice of selection material.Materials and Methods. The ability to the resumption of full-fledged species characteristics on the culture nutrient agar medium after long-term storage of the biomaterial in the form of a lyophilizate under conditions of low positive +4°C and ultra-low temperatures of -80°C of Alternaria alternata (Fr.) Keissl., Bipolaris sorokiniana Shoemaker and Fusarium solani (Mart.) Sacc. strains stored in the State Collection of Phytopathogenic Microorganisms of the All-Russian Research Institute of Phytopathology (ARRIP) was studied. The viability of fungi was judged by their ability to form spore-forming colonies on a nutrient medium, pathogenicity and phytotoxicity by the reaction of test culture seedlings to the effects of spore suspensions and culture fluid filtrates.Results. Long-term storage of Alternaria alternata, Bipolaris sorokiniana and Fusarium solani strains in a freeze-dried state, both at low and ultra-low temperatures, did not adversely affect their viability. On the 14th day of culture on a nutrient medium, fungal strains formed sporulating colonies comparable to the control variants. Comparison of pathogenicity signs in fungal strains before the experiment and after storage did not reveal significant differences between the variants. When studying the effect of the culture liquid filtrates of fungal strains on the development of the test culture, a differentiating effect of the storage regime at +4oC was established, while under ultra-low temperatures the results in the variants practically did not differ.Conclusion. The results of the study were showed that the lyophilization of biomaterial,including imperfect species of fungi for long-term storage at low positive and ultra-low temperatures is relevant and in demand in many scientific and industrial institutions.

Electrochemical detection of amine neurotransmitters is drastically different in buffer solutions, in vivo, and cell culture systems

Detection of neurotransmitters requires high sensitivity and temporal resolution, favoring electrochemical techniques for the sensing mechanism. However, electrochemical detection of amine neurotransmitters is highly dependent on electrode surface condition and thus, results obtained in clean buffer solutions are not directly applicable to the real measurement environment in vivo or in vitro. In these more complex electrolyte solutions, the presence of antioxidants and surface-adsorbing molecules drastically alters the redox characteristics of amine neurotransmitters, their precursors and metabolites. Accordingly, we surveyed their redox characteristics in the phosphate buffered saline (PBS), cerebrospinal fluid (CSF) and cell culture medium, with high-sensitivity electrodes made of single-walled carbon nanotube network.The concentration of surface-fouling molecules was lowest in the PBS and highest in the culture medium. Accordingly, electrochemical reaction kinetics were facile in the PBS and sluggish in the culture medium. Surprisingly, analyte molecular structure had much more importance in the CSF compared to other electrolytes, however the reaction kinetics remained to be generally slower in the CSF compared to when measured in the PBS.Whereas the CSF also contains L-Ascorbic acid and uric acid that are electrochemically active interfering molecules, they are either completely absent or can be omitted in the in vitro setting. On the contrast, the culture medium contains substantially higher concentration of surface-adsorbing molecules that causes more significant fouling of electrode and thus loss of sensitivity. As the in vitro brain-on-a-chip applications are rapidly being adopted, direct comparison of these different experimental settings was essential to understand their implications for electrochemical sensors.

Clinical Insights and Outcomes in Community-Acquired Acute Bacterial Meningitis versus Postoperative Bacterial Meningitis.

To compare the demographics, clinical characteristics, and in-hospital mortality rates between community-acquired bacterial meningitis cases and postoperative bacterial meningitis. Analytical study. Place and Duration of the Study: Department of Infectious Diseases and Clinical Microbiology, Diskapi Yildirim Beyazit Training and Research Hospital, Ankara, Turkiye, from 2016 to 2022. A total of 153 patients diagnosed with bacterial meningitis were included and categorised into two groups: 95 (62.1%) with community-acquired bacterial meningitis (CABM) and 58 (37.9%) with postoperative bacterial meningitis (POBM). Demographics, clinical features, laboratory, paraclinical findings, treatments, and outcomes of the cases were compared. Data were retrieved using a standard data collection form from the electronic medical records. A substantial portion (58.8%) of all patients had comorbidities. Fever was the common symptom in all groups. Headache, neck stiffness, nausea, and vomiting were more often observed in the CABM group (p <0.001). Upon admission, the CABM exhibited higher levels of white blood cell count, C-reactive protein, and procalcitonin (p = 0.017, p = 0.004, p = 0.007, respectively). Overall 33.1% had positive cerebrospinal fluid cultures. The overall mortality rate was 26.8%. POBM was associated with longer hospital and intensive care unit (ICU) stays (p <0.001). Shorter treatment durations, lower Glasgow coma scale scores (GCS), higher Charlson Comorbidity Index values, and elevated markers of inflammation were related to mortality. This study illuminates the differences in clinical presentations and outcomes between community-acquired and postoperative bacterial meningitis. It also suggests that factors such as lower GCS scores, comorbidities, and elevated inflammation markers at the last follow-up may be associated with unfavourable clinical outcomes in bacterial meningitis. Postoperative meningitis, Central nervous system infection, Cerebrospinal fluid, Antibiotics.

Endoscopic nasal multilevel skull base reconstruction combined with lumbar cistern drainage in the treatment of infection caused by cerebrospinal fluid leakage: A case report.

Traumatic cerebrospinal fluid leakage can cause complications such as meningitis, ventriculitis and brain abscess. It is necessary to formulate individualized treatment strategies, such as the use of antibiotics and skull base reconstruction methods. The application of nasal septum mucosal flap can significantly reduce the incidence of cerebrospinal fluid leakage. Neuroendoscope has been widely used in the treatment of skull base diseases, and the application of continuous lumbar cistern drainage technology has effectively controlled cerebrospinal fluid leakage. This paper introduces a case of long-term cerebrospinal fluid leakage complicated with infection. Neuroendoscopic multilevel skull base reconstruction combined with lumbar cistern drainage has achieved good clinical results, and this combined treatment is rarely reported in the literature. In order to promote the surgical effect of cerebrospinal fluid leakage, this combined treatment scheme is introduced here. A 43-year-old male was admitted with headache for 7 days, aggravation with fever and vomiting for 2 days. Cerebrospinal fluid culture suggests central nervous system infection, history and symptoms suggest traumatic cerebrospinal fluid rhinorrhea, and computed tomography (CT) shows old skull base fracture. Intracranial infection was controlled after anti-infection treatment with sensitive antibacterial drug ceftriaxone sodium. Repair of cerebrospinal fluid rhinorrhea by transsphenoidal endoscope. Continuous lumbar cistern drainage (LCD) was performed after operation to promote the healing of the leak. After comprehensive treatment, the patient did not have CSF rhinorrhea again and was discharged. Antibiotics combined with endoscopic multi-segment skull base reconstruction and lumbar cistern drainage are effective in treating infection caused by cerebrospinal fluid leakage.

The analysis of recombinant insulin production technologies

Aim. To analyze current trends in insulin production and expression systems used to obtain recombinant proteins. Materials and methods. The specified goal was achieved using the methods of content analysis, comparative, logical, analytical and generalization of information. The research materials were publications in scientific periodicals, official websites of manufacturing companies. Results. It has been found that the following expression systems are traditionally used for the commercial production of recombinant human insulins: bacterial – Escherichia coli, and yeast – Saccharomyces cerevisiae. But to meet the global need for insulin, it is necessary to develop new effective expression systems. Therefore, the use of other eukaryotic insulin expression systems that would be suitable for large-scale production is currently being studied. Among such systems, transgenic plants, which are characterized by the absence of potential human pathogens and the presence of post-translational protein modification mechanisms similar to human ones, are promising for introduction into insulin production. Currently, studies using Arabidopsis thaliana, tobacco, lettuce and strawberry plants are successful. Stem cells – embryonic, mesenchymal and induced pluripotent are also considered promising. The methods used in the large-scale production of recombinant insulin based on the synthesis of proinsulin and the two-chain method have been characterized. The technological flowcharts of both technologies have been drawn up, the advantages and disadvantages of each are given. Conclusions. The analysis of data from the scientific literature has shown that the main methods of producing insulin preparations since the 1980s remain pro-insulin and two-chain methods, which are based on recombinant DNA technologies. The pro-insulin method is considered more efficient and cost-effective compared to the two-chain method since this technology consists of working with a single recombinant strain. The choice between these two methods depends on the specific needs of the manufacturer: for some cases a fast method with proinsulin synthesis is rational, for others – a more accurate and controlled two-chain method. The bacteria – Escherichia coli and yeast – Saccharomyces cerevisiae remain the expression systems used in the existing large-scale production technologies. But using E. coli, insulin precursors are produced in inclusion bodies, and fully functional polypeptides are obtained by solubilization and refolding steps. The yeast-based system yields a soluble insulin precursor that is secreted into the culture fluid, but requires prior humanization due to the risks of an immune response in humans. Thus, current production technologies cannot meet the growing demand for available insulin due to limited production capacity and high production costs, so research is being conducted to find new efficient expression systems, such as plant and mammalian cells, including Arabidopsis thaliana, tobacco, lettuce, strawberry, stem cells.

Съвременен атомистичен модел на изкуството. Част трета

The Contemporary Atomistic Model of Art sought represents an ontogenetic process of creation, communication and perception of the artwork in the environment that surrounds us and that is within us. Instead of immutable wholes (holism), we have infinite sets of processes of connection and disconnection, merging and splitting of “nuclei” (atomism) where interactions are clearly visible. Through art, thought of as the porous structure of society with permeable sites of relation, each image and each material form of an artwork is only a connective element with values and other forms that are transferable in society. This is a principle of dynamic connection in which form is a kind of representation and a potential condition of exchange. The in-between zone has been distinguished, bearing its own traditions and recognizing both the connectedness as well as the separate items that are connected. Fluid culture atomism (fluid atomism) is where we observe the dynamics in interactions in an ever-changing structure that is itself made up of separated atomic units briefly grouped into more complex molecular formations, with all the connections between them being impermanent and temporary. Both the internal structures and the state of the whole change. The interactions of individual units are a key factor in the analysis of processes in art. These processes are embedded in perishable, dynamically transforming networks of ‘private’ art worlds, the sum of which is not the Universal World but a momentary state in an ever-changing system. The relationship between the individual artist and the overall system of organized artistic life passes through interactions of a socialpsychological type in organized temporary groups of artists. This article discusses the possible relations between the field of social psychology and art. Emphasis is placed on the aspects of innovative artistic inquiry, discussed as the singular and the unique in art as opposed to the established order. Innovation in art is juxtaposed with innovation in social bonding as a social psychological problem of creativity. Individual creativity is compared to the creativity of groups and the particularities of the creative processes inherent to individual artists. Such an interpretation develops further the idea of an art world seen as impermanent and dynamically changing networks of ‘private’ art worlds. Among the autonomous zones defined by the individual and the group are found shared zones through which polar differences are harmonized. Individual artistic innovation is juxtaposed with innovative practices that are formed through the action of the groups.

Clinical and bacteriological profile and antibiotic sensitivity pattern in spontaneous bacterial peritonitis among children with idiopathic nephrotic syndrome

Background: Spontaneous bacterial peritonitis is a serious complication of childhood nephrotic syndrome (NS). A precise knowledge of organism causing peritonitis is important primarily to treat infection and decrease morbidity, prevent antibiotic resistance and finally to reduce mortality. Objectives were to observe the clinical and bacteriological profile and antibiotic sensitivity pattern of peritonitis in childhood NS. Methods: This cross-sectional observational study was conducted in pediatric nephrology department of Bangabandhu Sheikh Mujib medical university (BSMMU). The 44 diagnosed patient of spontaneous bacterial peritonitis among childhood idiopathic NS were enrolled as cases. The peritoneal fluid was obtained following standard procedure and examined for gross appearance, cytogical and biochemical analysis, microscopic examination with gram stain and peritoneal fluid culture along with antibiotic sensitivity. Results: All patients had complaints of abdominal pain followed by fever, vomiting, lethargy and anorexia. All cases had edema and ascites followed by abdominal tenderness, abdominal wall rigidity, rebound tenderness and cellulitis in areas other than abdominal wall. Peritoneal fluid showed neutrophilic pleocytosis and exudative fluid. We observed 27.27% gram + cocci, 6.82% gram-bacilli in gram stain examination. Here, only 6.9% cases showed positive growth including 2.3% E. coli, 2.3% Pseudomonas, 2.3% Acinetobacter and remaining 93.1% cases showed no growth. We also described the antibiotic sensitivity pattern in this study. Conclusions: In our study, patients predominantly had abdominal pain, fever, edema, ascites and abdominal tenderness. We found only 6.9% cases showed positive growth which included E. coli, Pseudomonas and Acinetobacter and demonstrated the antibiotic sensitivity and resistance pattern for these organisms.

The clinical significance of intraoperative lavage fluid culture during pancreaticoduodenectomy on organ/space surgical site infection

Organ/space surgical site infection (SSI) are common after pancreaticoduodenectomy (PD). There is limited research on the clinical impact of intraoperative lavage fluid contamination in patients undergoing PD. One hundred five patients who underwent PD between August 2022 and July 2023 were retrospectively enrolled. The intraoperative bile and peritoneal lavage were collected for bacterial culture. Postoperative drainage bacterial cultures were performed every 2–3 days thereafter until drains were all removed. The bacteria isolated from intraoperative lavage fluid, intraoperative bile, and postoperative drainage fluid were examined in detail. The risk factors associated with positive intraoperative lavage fluid culture were analyzed through both univariate and multivariate analyses. Organ/space SSI occurred in 59(56.2%) of the 105 patients. The positivity rates of cultures in intraoperative lavage fluid, intraoperative bile, and postoperative drainage fluid were found to be 41.0%, 67.6%, and 84.8%, respectively. Patients with positive intraoperative lavage fluid culture had a significantly higher occurrence of organ/space SSI compared to the negative group (69.0% vs. 29.4%, P < 0.001). Preoperative biliary drainage (PBD) was identified as the only independent risk factor for the contamination of intraoperative lavage fluid (OR = 7.687, 95% CI: 2.164–27.300, P = 0.002). K. pneumoniae was the most common isolates both in the intraoperative lavage fluid and postoperative drainage fluid. Intraoperative lavage fluid contamination closely correlated with organ/space SSI after PD. Meanwhile, PBD was the only risk factor for the contamination of intraoperative lavage fluid.

Comparison of the Mitophagy and Apoptosis Related Gene Expressions in Waste Embryo Culture Medium of Female Infertility Types.

Mitochondria is an important organelle for the oocyte-to-embryo transition in the early embryonic development period. The oocyte uses mitochondria functionally and its mitochondrial DNA (mtDNA) content as the main energy source in the embryo development at the preimplantation stage. The aim of this study is to compare mitophagic, apoptotic and humanin gene expressions from the culture medium fluid in which embryos are developed and monitored among normoresponder (NOR), polycystic ovary syndrome (PCOS), young and older patients with poor ovarian reserve (POR). The study groups consisted of infertile patients who applied to the Bahçeci Umut IVF Center as NOR (Control), PCOS, POR-Advanced (POR-A) and POR-Young (POR-Y). After the isolation of total RNA from the collected samples, MFN1, MFN2, PINK1, PARKIN, SMN1, SMN2, p53 and Humanin gene expressions were determined by Real Time-PCR. The average age of only the POR-A was determined to be higher than the NOR (p < 0.001). The MFN1, SMN2 (p < 0.05), Humanin and p53 gene expressions (p < 0.001) increased, while PINK1 gene expression decreased (p < 0.05), in the POR-Y compared to the NOR. A decrease in MFN2, PARKIN (p < 0.05) and PINK1 gene expressions was determined in the PCOS compared to the NOR (p < 0.001). Furthermore, a decrease was observed in MFN2, PINK1 (p < 0.001) and Humanin gene expressions compared to the NOR (p < 0.05). The current data are the first in the literature determining the apoptotic and mitophagic status of the oocyte. The current results prove that waste embryo culture fluid may provide a non-invasive profile for important cellular parameters such as mitochondrial dysfunction in female infertility. The evaluation of significant cellular parameters can be performed much earlier without any intervention into the embryo.

Etiologies and comorbidities of meningitis deaths in children under 5 years in high-mortality settings: Insights from the CHAMPS Network in the post-pneumococcal vaccine era

The role of meningitis in causing deaths and in children under 5 is unclear, especially since widespread use of vaccines to prevent common causes of meningitis. Child Health and Mortality Prevention Surveillance (CHAMPS) uses post-mortem minimally invasive tissue sampling (MITS) and ante-mortem data to explore death causes. We aimed to assess meningitis's contribution to mortality and identify causative pathogens in children under 5 within CHAMPS Network sites. In this observational study, we analyzed deaths in live-born children <5 years of age that occurred between December 16, 2016, and December 31, 2023, in CHAMPS catchments in six sub-Saharan African countries (Ethiopia, Kenya, Mali, Mozambique, Sierra Leone, South Africa) and Bangladesh. MITS was conducted within 24-72h of death, including blood and cerebrospinal fluid (CSF) culture, multi-organism targeted nucleic acid amplification tests on blood, CSF and lung tissue, and histopathology of lung, liver and brain. Expert panels at each site reviewed data to attribute causes of death following ICD-10 standards. Meningitis was in the causal pathway for 7.0% (270/3857) of deaths; in 4.8% (13/270) meningitis was considered the underlying condition. Neonates accounted for 65.9% (178/270) and infants or children 34.1% (92/270). Among neonatal meningitis deaths, 55.6% (99/178) occurred ≥72h post-hospital admission; and common pathogens were Acinetobacter baumannii (49.5%, 49/99; mainly from South Africa) and Klebsiella pneumoniae (40.4%, 40/99). Forty-four percent (79/178) of neonatal meningitis deaths were community-associated, primarily due to K. pneumoniae (35.4%, 28/79) and Escherichia coli (13.9%, 11/79). Among infant and child meningitis deaths, 43.5% (40/92) occurred ≥72h post-admission; and common pathogens were K. pneumoniae (42.5%,17/40) and A. baumannii (17.5%, 7/40). Among community-associated meningitis deaths in infants and children (56.5%, 52/92), Streptococcus pneumoniae (34.6%, 18/52) and K. pneumoniae (19.2%, 10/52) were common pathogens. Pathogen prevalence varied by region. Our study highlights meningitis as a significant contributor to under-5 mortality in low-middle-income countries. The prominent role of K. pneumoniae and A. baumannii, particularly in healthcare settings and specific regions, highlights the need for better infection control, targeted interventions, and more effective treatment strategies.

Zero incidence of culture-positive septic arthritis and low infection rate following ACLR with all-soft tissue quadriceps tendon autograft: An analysis of 1053 cases.

To evaluate the infection rate following anterior cruciate ligament reconstruction (ACLR) using all-soft tissue quadriceps tendon (ASTQT) autograft. All primary ASTQT autograft ACLRs within a single surgeon's prospectively collected database from 2011 to 2021 were retrospectively reviewed. No topical antibiotics were administered and no graft-soaking with antibiotics was performed during the study period. Patients who underwent multiligament knee reconstruction or a cartilage restoration procedure were excluded. Patients who underwent a subsequent procedure, including irrigation and debridement (I&D) of the knee joint, were included. Case-specific data, including fluid culture analysis, antibiotics (type, route of administration and duration), time to debridement and method of debridement, were collected. Descriptive statistics were utilized to analyze demographics, incidence and possible association between the need for I&D and concomitant meniscus surgery. Out of 1053 cases (mean age: 20.2 ± 6.3, 44.6% female), four patients (0.38%) (mean age: 18.5 ± 4.0, 25% female) underwent subsequent I&D (arthroscopic I&D only [n = 1], graft harvest site I&D only [n = 1], combined graft harvest site and arthroscopic I&D [n = 1] and tibia wound and arthroscopic I&D [n = 1]). There was no significant difference with regard to demographics. No joint fluid cultures returned positive; one wound culture returned positive for Methicillin-susceptible Staphylococcus aureus from their graft harvest site. The time to I&D ranged from 18 to 23 days. Concomitant meniscectomy or meniscal repair was not associated with requiring surgical I&D. All patients who underwent I&D were prescribed antibiotics for a minimum of 10 days and a maximum of 31 days (mean: 16.25 days). Three patients (75%) who underwent I&D ultimately returned to sport. One patient was lost to follow-up. ACL grafts were retained in all patients. The incidence of culture-positive septic arthritis following ASTQT autograft ACLR is 0%, while the overall need for I&D of 0.38% is low and not related to concomitant meniscal procedures or patient-specific factors. Level IV.

Case of delayed diagnosis of combined urogenita and pulmonary tuberculosis in a patient with abnormal uterine bleeding

According to the World Health Organization tuberculosis remains a global health issue for both adult and pediatric populations worldwide. Among women the peak incidence occurs during the active reproductive age, with pregnant women being 1.5–2 times more likely to be affected and experience more severe symptoms than non-pregnant women. In the Altai Region, the epidemiological situation of tuberculosis is characterized by instability, with the incidence rate among women reaching30.5 per 100 000 of the corresponding population in 2022. Delayed diagnosis and treatment can lead to serious complications, including fatal outcomes for both mother and fetus. This article describes a clinical observation of a case of urogenital and pulmonary tuberculosis diagnosed three months after premature abdominal delivery. The course of pregnancy was complicated by acute pleuritis at 13–14 weeks, however, negative results of bacteriological culture of pleural fluid led to the absence of specific tuberculosis treatment and the development of chronic subcompensated placental dysfunction. Three months after delivery, a 34-year-old patient was admitted to the gynecological department of the emergency hospital with abnormal uterine bleeding. The diagnosis was confirmed by histopathology of an endometrial sample revealing tuberculous granulomas without caseous necrosis with epithelioid giant cells of Pirogov – Langhans. Subsequently, generalized tuberculosis was diagnosed in the preterm infant. The negative impact of undiagnosed combined urogenital and pulmonary tuberculosis on the course and outcome of pregnancy is demonstrated, including the development of anemia, placental dysfunction, preterm delivery, puerperal complications, and adverse perinatal outcomes.

The occurrence of remitting seronegative symmetrical synovitis with pitting edema (RS3PE) after arthroplasty mimicking a periprosthetic joint infection: A case report and literature review.

As the elderly population grows, the number of joint arthroplasty surgeries is also increasing. Periprosthetic joint infection (PJI) is a postoperative complication that occurs in 1%-2% of the arthroplasties. Once it occurs, PJI is refractory to treatment. Similar symptoms of PJI, including joint synovitis and elevated body temperature, sometimes arise because of crystal arthritis, rheumatoid arthritis, or other inflammatory diseases. Precise diagnosis is essential for determining the optimal treatment strategy. An 81-year-old female patient with a history of bilateral knee arthroplasty presented with a high fever of 38 °C and was unable to walk due to swelling and pain in the bilateral lower extremities. Infectious conditions, such as cellulitis or PJI, were suspected. Imaging findings revealed bilateral knee joint synovitis with pitting edema around the lower extremities, and cultures of bilateral joint fluids were negative. No crystals were observed in the joint fluid. Laboratory data revealed highly elevated levels of inflammatory marker; however, antinuclear antibodies, including rheumatoid factor and cyclic citrullinated peptide, were not detected. Based on bilateral synovitis with pitting edema in the lower extremities, in addition to negative culture findings and normal antinuclear antibodies, the diagnosis of remitting seronegative symmetrical synovitis with pitting edema (RS3PE) was made. Steroid therapy was performed. The dose was gradually reduced, with the improvement of the symptoms. The inflammatory reaction promptly decreased and then normalized. With improved inflammation, the symptoms of pitting edema, pain in the bilateral lower extremities, and fluid effusion of the knee joints were reduced. She was able to walk without a cane, and her activities of daily living fully recovered. High fever and synovitis after joint arthroplasty do not necessarily indicate an infectious condition. Clinicians should be familiar with the occurrence of RS3PE, regardless of whether arthroplasty is performed.

Brain abscess caused by Mycobacterium tuberculosis in an immunocompetent patient: a case report and literature review.

Brain abscesses caused by Mycobacterium tuberculosis are rarely reported and are typically found in immunocompromised patients. The challenges in identifying the pathogen and the frequent delays in initiating appropriate therapy often result in a poor prognosis for patients. We herein report a rare case of a brain abscess caused by M. tuberculosis in a 63-year-old patient with a history of hypertension but no history of pulmonary tuberculosis. The patient was hospitalized twice because of worsening right upper limb weakness and speech difficulties. Both a pus culture and cerebrospinal fluid culture were negative. Ultimately, the diagnosis of M. tuberculosis infection was confirmed through next-generation sequencing and the tuberculosis-specific T-cell test (T-SPOT). The patient's symptoms improved following anti-tuberculosis treatment. This case highlights the importance of considering M. tuberculosis as a potential cause of brain abscesses, even in immunocompetent individuals, and underscores the need for early diagnosis for effective treatment.

Clinical Features Associated With Return to Pre-endophthalmitis Visual Acuity Following Presumed Infectious Endophthalmitis.

This study aimed to investigate clinical characteristics associated with return to pre-endophthalmitis visual acuity (VA) following treatment for presumed infectious endophthalmitis. This was a retrospective study of 74 eyes with endophthalmitis and VA recorded ≤ 12 weeks before presentation and 6 months after presentation between 2009 and 2018. Thirty-six of 74 eyes (49%) returned to preendophthalmitis VA. Eyes with a positive intraocular fluid culture had 71.5% lower odds of returning to pre-endophthalmitis VA. Nine of 10 eyes (90%) treated with initial pars plana vitrectomy failed to return to pre-endophthalmitis VA. Endophthalmitis following cataract surgery was a characteristic of eyes that returned to pre-endophthalmitis VA. Symptom duration, time to presentation, and treatment with systemic corticosteroids were not significant predictors of visual recovery. Just under 50% of eyes with presumed infectious endophthalmitis returned to preendophthalmitis VA. A positive intraocular culture is associated with failure to return to pre-endophthalmitis VA. [Ophthalmic Surg Lasers Imaging Retina 2024;55:XX-XX.].

Streptococcus equi Subspecies zooepidemicus Endocarditis and Meningitis in a 62-Year-Old Horse Rider Patient: A Case Report and Literature Review.

The present article presents a case report and literature review concerning the Streptococcus equi subspecies zooepidemicus (SEZ), a rare zoonotic pathogen in humans. The case involves a 62-year-old man with no prior heart disease, presenting with endocarditis, pneumonia, and meningitis following close contact with a horse. The patient underwent urgent aortic valve replacement due to severe valvular damage caused by the infection. Blood and cerebrospinal fluid cultures confirmed the presence of SEZ, and the patient was treated with a combination of antibiotics, followed by a successful step-down to oral therapy using linezolid. A review of 25 additional Streptococcus equi endocarditis cases highlights the rarity of the condition, its association with animal contact, and its tendency to cause multi-site infections, such as pneumonia and meningitis. Early diagnosis, appropriate antibiotic therapy, and, in severe cases, surgical intervention are critical for a favorable outcome. This report emphasizes the importance of recognizing zoonotic infections in at-risk populations and the potential need for public health surveillance in these scenarios.

Severe co-infection caused by difficult-to-diagnose hypermucoviscous Klebsiella pneumoniae K1-ST82 in a patient with COVID-19: a case report

BackgroundCo-infection with Klebsiella pneumoniae presents a significant concern in hospitalized patients with coronavirus disease (COVID-19), increasing the risk of severe disease progression. Hypervirulent (hv) and hypermucoviscous (hm) K. pneumoniae (Kp) has gained prominence in Asia due to its capacity to cause invasive community-acquired infections. However, recognition of hvKp/hmKp co-infections in the context of COVID-19 remains limited. We report a severe case of rapidly progressing co-infection with hmKp exhibiting “difficult-to-diagnose” phenotypes in a hospitalized patient with COVID-19.Case presentationA 61-year-old woman with COVID-19 initially exhibited mild symptoms resembling the common cold. However, her condition rapidly deteriorated over 7 days, leading to hospital admission with the development of dyspnea. The patient required supplemental oxygen, antibiotic treatment, and mechanical ventilation. Gram-negative bacteria with atypical phenotypes were isolated from alveolar lavage fluid and blood cultures. Both strains formed small, glossy, non-lactose-fermenting colonies on clinically relevant media and were susceptible to ampicillin. Conventional biochemical tests failed to identify the Enterobacteriales strains owing to the urease-negative phenotype. Consequently, the identification of K. pneumoniae was difficult until matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis was performed. A positive string test indicated mucoviscosity, but with variability in the material used for stretching colonies. Whole-genome sequencing performed on the MiSeq and GridION platforms revealed the blood-derived strain JARB-RN-0063 as belonging to serotype K1 and sequence type (ST) 82. The hvKp-associated genes rmpA and iroCD were located on a 5.0-Mb chromosome, and iucABCD-iutA was identified on a 217.9-kb IncFIB(K)/IncR-type plasmid. Therefore, JARB-RN-0063 was genetically classified as hvKp with a Kleborate virulence score of 3. The intrinsic penicillinase gene blaSHV was defective owing to an IS1F element insertion, resulting in the strain being atypically susceptible to ampicillin.ConclusionsThis is the first case of severe COVID-19-associated co-infection with a difficult-to-diagnose K. penummoniae strain. Notably, co-infection by the hmKp K1-ST82 clone exhibited atypical phenotypes, including stunted growth, non-lactose fermentation, urease-negative reaction, ampicillin susceptibility, and abnormal mucoviscosity, posing diagnostic challenges for clinical laboratories and impedes the identification of hvKp/hmKp. Delayed identification may worsen patient outcomes, highlighting the need for increased clinical awareness of such difficult-to-diagnose clones to prevent deterioration.

Improving the microbiological diagnosis of fracture-related infection and prosthetic joint infection through culturing sonication fluid in Bactec blood culture bottles.

Sonication of surgically removed implants appears to optimize the microbiological diagnosis in orthopedic implant-associated infections (OIAI). However, reports of infection with negative cultures can still reach high rates. A study evaluating the inoculation of sonication fluid into blood culture bottles (SFBCB) in patients with fracture-related infection (FRI) and prosthetic joint infection (PJI) is necessary. This study compared the accuracy SFBCB over the conventional sonication fluid cultures (CSFC) and tissue culture (TC). Consecutive patients who underwent implant removal surgeries due to any reason had their implants sonicated according to standardized method. Definitions of PJI and FRI were based upon criteria by European Bone and Joint Infection Society (EBJIS) and Metsemakers, respectively. Between three to five intraoperative tissue samples were processed. The implant`s sonication fluid was seeded onto sheep blood agar, chocolate agar, thioglycolate broth and on tryptic soy broth for CSFC, while was also inoculated into blood culture bottles and incubated in the automated system during 5 days for SFBCB. Overall, 74 patients were analyzed, of which 57 with OIAI (48 FRI and 09 PJI) and 17 aseptic failures (03 arthroplasties and 14 osteosynthesis). Interestingly, SFBCB demonstrated significantly higher sensitivity compared to CSFC (96.5% [95% CI, 88-100] vs. 78.9% [95% CI, 66-89], p = 0.004), and to TC (96.5% [95% CI, 88-100], vs. 57.9% [95% CI, 44-71], p < 0.001), whereas there were no significant differences in specificity between the three methods. In comparison to CSFC and TC, SFBCB improved sensitivity for diagnosing OIAI without compromising specificity.