Signs Of Infection Research Articles

Homemade pericardial bifurcated graft for Q fever-infected abdominal aortic aneurysm open repair: a case report

Q fever is a zoonotic infection caused by Coxiella burnetii. In rare cases, it can lead to vascular complications, including infected aneurysms. Successful treatment involves surgery and antibiotics, but there is no established consensus or clear recommendation for the choice of material graft. We report a case of abdominal aortic aneurysm infected by C. burnetii treated by open surgery with complete resection of the aneurysm and homemade bovine pericardial bifurcated graft reconstruction and long-term antibiotherapy using doxycycline. One year postoperatively, the patient had no sign of persistent infection or vascular complication. Moreover, C. burnetii immunoglobulins titers decreased 6 months postoperatively.

Skin manifestations and human immunodeficiency virus infection in the Tigray region, Ethiopia: Implications for clinical management and epidemiologic surveillance

AbstractBackgroundPatients with human immunodeficiency virus (HIV) infection may present a large variety of skin manifestations, often associated with significant morbidity. In turn, dermatological diseases may represent an early sign of HIV infection, particularly in resource‐limited settings.ObjectivesThis study aimed to assess the spectrum of dermatological diseases and their potential value as clinical proxies for the early detection and management of HIV in a rural region of Ethiopia.MethodsThe study was performed on a population of 67,161 patients with skin diseases attending the Italian Dermatological Center in Mekele, Tigray region, Ethiopia. HIV infection was diagnosed in 1892 individuals (1065 female), all naïve to antiretroviral therapy.ResultsInfectious skin diseases were present in 57.2% of the total HIV population. Among the infectious skin manifestations, dermatophytosis (20.5%), impetigo (5.9%), candidiasis (4.7%) and molluscum contagiosum (4.7%) were significantly more represented in patients with HIV infection (p < 0.001). Regarding the noninfectious manifestations, pruritus and atrophy of the papillae on the tongue were significantly associated with HIV (p < 0.001). Notably, females had a significantly higher incidence of dermatophytosis and seborrheic dermatitis as compared to their male counterparts (p < 0.001), whereas scabies, psoriasis and leishmaniasis were significantly more frequent in males (p < 0.001).ConclusionsSkin manifestations are common in HIV patients, often reflecting compromised immune status. In addition, Dermatophytosis and pruritus were the most frequently reported manifestations of HIV, thus representing useful clinical proxies to raise the suspicion of an underlying HIV infection. Besides, gender differences in skin manifestations should also be considered in the clinical evaluation.

Pulmonary Thromboembolism and Myocarditis Resulting from a Large Pacing-Lead-Associated Right Ventricular Thrombus in a Dog with Chronic Cough as Presenting Sign

In the present case report, we describe the clinical course and postmortem findings of a 12-year-old Labrador retriever dog with a third-degree atrio-ventricular block that developed a chronic cough, and later dyspnea and weakness as a result of massive pulmonary thromboembolism 3 years after implantation of a transvenous permanent pacemaker. A large soft tissue mass was seen in the right ventricular chamber around the pacing lead with echocardiography. Initially, this was thought to be caused by mural bacterial endocarditis based on hyperthermia, severe leukocytosis and the appearance of runs of ventricular tachycardia, the latter suggesting myocardial damage. While blood culture results were pending, antibiotics were administered without a positive effect. Due to clinical deterioration, the owner elected for euthanasia and a post-mortem examination confirmed a right ventricular thrombus and surrounding myocarditis, without signs of bacterial infection, and a massive pulmonary thromboembolism. We conclude that pulmonary thromboembolism should be considered in dogs with a cough that have an endocardial pacing lead implanted. Serial screening for proteinuria before and after implantation of an endocardial pacing lead would allow timely initiation of prophylactic antiplatelet therapy. Local myocarditis can develop secondary to an intracavitary thrombus, which can subsequently lead to runs of ventricular tachycardia.

#578 Calcium-channel blockers chyloperitoneum: an underrated complication in peritoneal dialysis

Abstract Background and Aims Bacterial peritonitis is the most feared complication for peritoneal dialysis (PD) patients. Together with abdominal pain and elevated white cell count in peritoneal effluent, the presence of a cloudy peritoneal effluent represents the main diagnostic criteria. The appearance of this last sign, even in an asymptomatic patient, always represents cause for concern and raises suspicion of an already subclinical peritonitis but can also represent other causes. Among acellular aetiologies for a cloudy peritoneal effluent, there is the presence of triglycerides, usually above 200 mg/dl, called chyloperitoneum, secondary to pancreatitis or concomitant calcium- channel blockers (CCBs) therapy. Most of dialysis patients are affected by hypertension. Considering the frequent necessity of limiting dosage of angiotensin 2 receptors blockers (ARB) and ACE inhibitors (ACE-I) for the risk of hyperkalaemia, CCBs frequently represent one of the most common prescribed antihypertensive drugs. Usually well tolerated and with limited adverse effects, literature demonstrates how they can induce, for not fully understood reasons (research supposed a role for the lipophilicity of these drugs, an impaired lymphatic absorption, an increased lympho-vascular dilatation or lymphatic hydrostatic pression) the presence of triglycerides in peritoneal effluent to levels causing chyloperitoneum. Frequently reported as anecdotical cases, especially in Asian studies, only limited information are available about influence of drug dosage or other concomitant therapies but is evident a higher frequency with lercanidipine assumption. Method We evaluated all patients undergoing peritoneal dialysis in our Centre in 2023. Chyloperitoneum (Fig. 1) diagnosis was obtained in cases of cloudy peritoneal effluent in asymptomatic patients with normal inflammatory indexes, normal white cell count on peritoneal effluent and negative cultural samples on peritoneal effluent associated with complete remission after fast peritoneal washes and reduction or discontinuation of CCBs. Results 16 patients underwent PD in our Centre during 2023: 4 automated (APD) and 12 ambulatory (CAPD). All of them were affected by hypertension and 10 of 16 (2 APD and 8 CAPD) were already in chronic therapy with CCBs (5 with lercanidipine, 4 with lacidipine and 1 with barnidipine), all at maximum accepted dosage. 4 patients presented during 2023 one or more episodes of cloudy peritoneal effluent without any sign or symptom of infection. All these patients were in CAPD and in therapy with lercanidipine and underwent to full remission after fast peritoneal washes; for 2 of them was necessary to discontinue CCBs therapy while for the other 2 dose reduction was fair. In 1 patient was recently associated oral anticoagulant therapy and in another 1 was recently associated dual antiplatelet therapy. None of these patients presented more episodes and all of them are still in PD. Among the other 8 patients in CCBs therapy without episodes of chyloperitoneum, only 1 was already in therapy with single antiplatelet therapy and none of them with double one or with oral anticoagulant. Conclusion cloudy peritoneal effluent is always cause for concern for Nephrologists since that it could represent, event without any other sign or symptom of infection, an already subclinical bacterial peritonitis. Most of dialysis patients are also affected by hypertension. Since usage of ARB and ACE-I is limited by risk of hyperkalaemia, CCBs represents one of the most prescribed antihypertensive drugs. For PD patients, however, the risk of chyloperitoneum must be considered since, even if it can be easily corrected, it could also affect therapy and patient management. Described in literature as only an anecdotical complication, our study shows that the incidence could be much higher and appears to be linked a specific molecule, lercanidipine, taken at higher dosage and to CAPD. Concomitant therapies as dual antiplatelet or oral anticoagulant therapy could represent a stimulating factor but other studies, with more numerous patients, are needed for further considerations.

#2460 Haemodialysis-related periarticular calcifications as cause of recurrent severe inflammatory state

Abstract Background and Aims End stage chronic kidney disease (CKD) and haemodialysis (HD) are associated with disturbances in mineral and bone turnover ultimately leading to chronic kidney disease–mineral and bone disorder (CKD-MBD), which affects more than 90 % of patients with stage 5D CKD. The primary changes observed in CKD–MBD involve elevated phosphorus levels, decreased calcium levels, insufficient serum vitamin D, and heightened release of parathyroid hormone from the parathyroid glands, leading to secondary hyperparathyroidism. CKD-MBD leads to vascular calcification, increasing cardiovascular risk. There is also a correlation between abnormal bone remodeling activity in CKD-MBD and the likelihood of calcification in soft tissues. In rare instances, profound calcification occurs in periarticular tissues, resulting in severe inflammation and manifesting as systemic disease with articular involvement clinically. The objective of this case report is to demonstrate a recurrent inflammatory condition caused by severe periarticular calcification in a patient on HD. Case report We present a case of a middle-aged white male diagnosed with hypertension, hypercholesterolemia, chronic obstructive pulmonary disease, hepatitis C, and end-stage renal disease caused by hydronephrosis. He was undergoing HD since July 2020. From summer 2021 the patient experienced recurrent fever and arthralgias in the hips, elbows, and shoulders. Frequent acute hospitalizations were needed due to recurring fevers and severe inflammatory response with markedly elevated acute phase reactants (CRP was repeatedly >200 mg/l), raising suspicion of infection. Laboratory and imaging tests however showed no clear signs of infection, and antibiotic therapy was ineffective. An x-ray of the right AC-joint showed multiple periarticular calcifications dorsally from the AC-joint. Later, due to severe pain and swelling an MRI-scan of right elbow joint was conducted, revealing an osteomyelitis-suspect finding of the olecranon, and olecranon bursitis. No bacteria were detected in the punctate of olecranon bursa. X-ray scans of the elbows revealed bilateral soft tissue calcification dorsally from the proximal ulna. The x-ray scan of the right shoulder revealed calcific expansion in the AC-joint area, leading to total destruction of the lateral part of the clavicle. MRI and CT scans showed severe periarticular calcification around AC- and glenohumeral joints without inflammatory involvement of the synovium. Bony erosions were observed due to the pressure of calcified tissue on the bone. Whole-body CT-scan showed no sites of infection but there was a periarticular calcification observed around the hip joints. A PET-CT scan of the whole body, neck, and upper extremities revealed no signs of malignancy or infections, but there was an increased uptake of 18F-fluorodeoxyglucose detected in several periarticular sites, indicating a multi-site inflammatory process resulting from severe periarticular calcifications. A dual-energy CT-scan of upper extremities was performed, excluding the accumulation of monosodium urate crystals. The cycle of multiple hospitalizations and antibacterial therapies was broken with the diagnosis of CKD and HD-related inflammatory periarticular calcification. Initially, the inflammation was addressed with high-dose glucocorticoids. However, the dose was successfully tapered during the first month of treatment, and the patient continued to do well on a maintenance dose of 5 mg/day of prednisolone. Subsequently, hospitalizations, antibiotics, or surgical procedures were no longer required. Conclusion Severe CKD and HD cause disturbances in mineral and bone metabolism, that can lead to periarticular calcification. Like in our presented case, multi-site calcifications may mimic infection or autoimmune rheumatoid conditions making the way to correct diagnosis cumbersome and costly. Imaging techniques help us distinguish periarticular deposits from inflammatory and infectious arthritis. In our case low-dose prednisolone effectively reduced inflammation, obviating hospitalizations and minimizing healthcare burden.

#1572 Recurrent parvovirus B19 infection-associated pure red cell aplasia in kidney transplantation

Abstract Background and Aims Anemia is frequent in kidney transplant (KT) recipients, with multiple potential causes. Parvovirus B19 (PVB19) infection-associated pure red cell aplasia (PRCA) becomes an important diagnosis in KT recipients experiencing persistent anemia, in whom other etiologies have been excluded. PVB19-associated PRCA is described in up to 27% of KT recipients with anemia and recurrent disease in up to 33% of cases. The authors describe a case of a recurrent PVB19-associated PRCA in a KT recipient. Method - Results A 42-year-old male with chronic kidney disease of unknown etiology underwent KT from a deceased donor after circulatory death in January 2021. He received induction immunosuppression (IS) with thymoglobulin and maintenance IS with prednisolone, tacrolimus, and mycophenolate mofetil (MMF). Three months after KT, the patient complained of progressive asthenia, and normocytic normochromic (NN) anemia was detected. A thorough investigation revealed normal leucocyte and platelet counts, low reticulocyte count, and no signs of bacterial infection, iron deficiency, or hemolysis; thyroid function, erythropoietin, folate, and vitamin B12 levels were normal, direct Coombs test was negative and no monoclonal spike was detected on protein electrophoresis. Endoscopic studies and cervico-thoraco-abdomino-pelvic computer tomography were unremarkable. Serum PCR of PVB19 was positive and confirmed the diagnosis of PVB19-associated PRCA. MMF was discontinued but anemia continued aggravating (nadir hemoglobin [Hg] level of 6.6 g/dL) with a sustained PVB19 load. He was admitted to the hospital, received blood transfusions, and was started on intravenous immunoglobulin (IVIG) 2 g/kg. A bone marrow aspirate was performed and was compatible with recovery after erythroid aplasia. The patient was discharged with Hg 8 g/dL and reduced PVB19 load. Although MMF remained suspended, and close monitoring of Hg and PVB19 load was performed, four months later he developed recurrent PVB19-associated PRCA, which motivated another hospital admission for IVIG with excellent response. In addition, he presented kidney dysfunction, and a kidney biopsy revealed borderline acute T-cell mediated rejection. In this setting, IS was altered to TRANSFORM SCHEEME. Four months later, he presented a second recurrence of PVB19-associated PRCA, requiring new hospitalization and treatment with IVIG. Considering the recurrent PVB19-associated PRCA, in a patient with chronic allograft dysfunction, high immunologic risk, and the foscarnet's probable nephrotoxicity, preventive therapy with IVIG (0.4 mg/kg) every 4 weeks was started. After 7 months of preventive IVIG infusion, no relapse was identified, the Hg is 11.5 g/dL (and increasing, without erythropoiesis stimulants) and the PVB19 load remains low. Conclusion PVB19-associated PRCA is characterized by persistent NN anemia with low reticulocyte counts, which is unresponsive to erythropoietin. One significant risk factor is induction IS, particularly thymoglobulin. In the setting of solid organ transplants, the absence of PVB19 antibodies does not exclude this diagnosis and viral detection should be performed. The initial therapeutic approach involves reducing IS. However, the risk of allograft rejection must be acknowledged. If this approach proves insufficient, IVIG treatment is usually successful. In our patient, considering the facts that allograft rejection limits the reduction of IS, the need for blood transfusions, and the inherent immunization, in a young patient that will possibly require a second KT, the undesirable nephrotoxicity of foscarnet, the successful response to IVIG, and patient's quality of life, chronic IVIG therapy was thought to be the best choice and proved efficacious in preventing relapses. Despite the absence of precise guidelines for chronic PVB19 infection management, maintenance therapy with prolonged IVIG infusions may be a therapeutic option for recurrent PRCA, but more studies are necessary to define the appropriate duration of treatment.

Impression Fracture of The Lateral Condyle of Tibial Plateau Complicated by Acute Peri-Implant Infection: A Case Report

Introduction. Deep infection after open osteosynthesis of tibial plateau fractures occurs in 9.9%. This rate is significantly higher than in surgical treatment of closed injuries of other localizations. Many foreign authors consider it necessary to improve protocols for the management of patients with comminuted plateau fractures in order to minimize or prevent the development of infection. Aim of the study is to discuss the treatment tactics of a patient with an intra-articular fracture of the tibial plateau after osteosynthesis, complicated by the development of early deep surgical site infection. Clinical case. A 71-year-old patient with compromised somatic status underwent osteosynthesis with a buttress plate and allogeneic bone grafting of the metaphyseal defect on the 12th day after injury. In 7 days after the occurrence of signs of infection, a revision surgery was performed. Later, a number of consecutive revisions were performed due to recurrences of the infectious process. The complex of measures against surgical site infection included the use of vacuum drainage systems and antibacterial spacers. Two years after the injury the wounds healed. The patient had a good functional result. Discussion. There are several approaches to the management of infection after osteosynthesis: wound debridement and retention of the implant, replacement of one implant with another, and removal of the implant with conversion to external fixation. Surgical treatment is mandatory if a surgical site infection after primary surgery occurs. Several consecutive interventions can be performed. Wound closure after revision is performed either with the installation of an active drainage system or the wound is closed with a VAC-system. The use of local antibacterial therapy in the form of antibacterial spacers reduces the rate of recurrent infection from 18.7% without their use to 10% of cases with their use. Conclusion. Successful treatment of infectious complications of osteosynthesis requires a team of like-minded specialists, which should include general practitioners, microbiologists, and clinical pharmacologists in addition to an orthopedic surgeon. To prevent such complications, it is important to reduce injury rate and improve the quality of primary osteosynthesis.

NAVIGATING THE UNCHARTED WATERS: MANAGING CONCURRENT CYTOMEGALOVIRUS MYOCARDITIS AND ALLOGRAFT REJECTION IN A PATIENT WITH HEART TRANSPLANTATION

Abstract A 49–year–old female with hypertrophic cardiomyopathy underwent orthotopic heart transplantation. She was cytomegalovirus(CMV)–positive and received a heart from a CMV–negative donor, so prophylaptic therapy was not administered. Initial immunosuppression included cyclosporine and induction with Basiliximab in a steroid–free regimen. The first routine biopsy (EMB) showed mild focal cellular rejection (grade 1A) and C4d positivity with granular aspect. Mycophenolate mofetil (MMF) was added. The second EMB, 7 days later, showed mild diffuse cellular rejection (grade 1B) and diffuse C4d positivity. Anti–HLA donor–specific antibodies (DSA) had increased anti–B13 levels (MFI=21298) compared to pre–transplantation tests. Echocardiography showed a normal ejection fraction (LVEF) and mild concentric hypertrophy (LVH). Treatment included pulse methylprednisolone therapy (1 g/day for three days) followed by oral prednisone with a slow tapering regimen, and increased MMF. CMV count weekly monitored was negative. The next two EMBs performed one week apart from each other described a grade 1A mild focal pattern while the 5th EMB (1 month and 2 weeks post–transplant) showed a grade 1A rejection together with focal mild fibrosis and eosinophils, so we replaced cyclosporine with tacrolimus, increased MMF and prednisone. At this time, the patient had no overt clinical signs of CMV infection but a CMV–PCR of 100847 IU/mL so ganciclovir 5 mg/Kg bid was started and CMV–PCR decreased to 42308 IU/mL after 1 week. Subsequently, she developed sinus tachycardia, mildly reduced LVEF, moderate LVH and diastolic dysfunction. Troponin was elevated. A new EMB revealed interstitial edema, diffuse ischemic injury, and eosinophilic inclusions suggesting CMV myocarditis. Treatment involved down–titrating MMF and Prednisone, administering standard intravenous immunoglobulin (IVIG), and high–dose Ganciclovir (7.5 mg/Kg bid). Leukopenia subsequently led to Ganciclovir down–titration. In the next days, the patient improved, CMV cleared, and leukocyte count normalized. She was discharged on Tacrolimus, MMF, Prednisone and Valganciclovir. Subsequent tests showed no cellular or antibody–mediated rejection (AMR), no CMV inclusions, recovered cardiac function, and markedly reduced anti–B13 DSA (MFI 3000). This case raises some concerns: in this context, the use of IVIG in the treatment of CMV infection and AMR appears reasonable, in support of antiviral and immunosuppressive therapy.

The quantification of southern corn leaf blight disease using deep UV fluorescence spectroscopy and autoencoder anomaly detection techniques.

Southern leaf blight (SLB) is a foliar disease caused by the fungus Cochliobolus heterostrophus infecting maize plants in humid, warm weather conditions. SLB causes production losses to corn producers in different regions of the world such as Latin America, Europe, India, and Africa. In this paper, we demonstrate a non-destructive method to quantify the signs of fungal infection in SLB-infected corn plants using a deep UV (DUV) fluorescence spectrometer, with a 248.6 nm excitation wavelength, to acquire the emission spectra of healthy and SLB-infected corn leaves. Fluorescence emission spectra of healthy and diseased leaves were used to train an Autoencoder (AE) anomaly detection algorithm-an unsupervised machine learning model-to quantify the phenotype associated with SLB-infected leaves. For all samples, the signature of corn leaves consisted of two prominent peaks around 450 nm and 325 nm. However, SLB-infected leaves showed a higher response at 325 nm compared to healthy leaves, which was correlated to the presence of C. heterostrophus based on disease severity ratings from Visual Scores (VS). Specifically, we observed a linear inverse relationship between the AE error and the VS (R2 = 0.94 and RMSE = 0.935). With improved hardware, this method may enable improved quantification of SLB infection versus visual scoring based on e.g., fungal spore concentration per unit area and spatial localization.

Bacteria Endocarditis Caused by Mycoplasma hyorhinis in a Juvenile, Immunosuppressed Pig (Sus scrofa domesticus) following Partial Heart Transplantation.

Domestic swine (Sus scrofa domesticus) are important translational models for cardiovascular transplant studies. This can be attributed to the anatomic and physiologic similarities of their cardiovascular system to humans. Transplant studies frequently employ clinically relevant immunosuppression regimens to prevent organ rejection postoperatively. Immunosuppression can lead to opportunistic infection, including presentations that are novel or poorly described in immunocompetent hosts. In this study, we describe the first case of Mycoplasma hyorhinis-induced endocarditis affecting the pulmonary valve in a juvenile, immunosuppressed pig following a partial heart transplantation procedure. Clinical signs of infection began at 15 d postoperation, were consistent with a variety of infectious agents, including Mycoplasma hyorhinis, and included lethargy, respiratory signs, and elevated white blood cell counts. By 28 d post procedure, lameness and soft tissue swelling around the left tarsus developed. Joint fluid obtained by arthrocentesis was PCR positive for Mycoplasma hyorhinis and negative for other tested pathogens. Despite antimicrobial treatment, the transplanted pulmonary valve developed leaflet thickening, stenosis, and insufficiency starting at 30 d after the procedure. At 86 d posttransplantation, the pig reached experimental endpoints and was humanely euthanized for necropsy and histopathology. The pulmonary valve had numerous dark red vegetative expansions of all 3 leaflets. Postmortem testing of a vegetative lesion was positive for Mycoplasma hyorhinis, confirming the etiologic agent responsible for endocarditis. Mycoplasma hyorhinis-induced endocarditis of an orthotopic transplanted pulmonary valve has yet to be described in swine. This case report demonstrates that infections following immunosuppression may present with novel or undercharacterized clinical signs.

The Mortality Rate in Neutopenic Children Population in Oncology an Algerian Study

Febrile neutropenia consecutive to the administration of chemotherapy constitutes the most serious and the most frequent complication of cytotoxic chemotherapies. It is often a sign of infection, being able to quickly turn in septicemia if no treatment is begun; it thus constitutes an emergency for diagnosis and therapeutics. The objective of this work is to study the epidemiological, clinical, biological, etiologic and evolutionary characteristics of the episodes of febrile neutropenia, to evaluate the importance of the infectious risk and the main involved germs, to identify the difficulties of the management and the follow-up of the children having developed a febrile neutropenia and finally. During our retrospective study concerning the episodes of febrile neutropenias diagnosed in the pediatric oncology unit of the pediatric department of the university hospital of Alger over a period of 04 years (from 1 January 2017 to 31 December 2020). 205 patients having solid tumor were collected. Among them 45 cases presented febrile episodes, the average age was 5.75 years with a maximum frequency of them were male, and the main motive for consultation was the fever. The average deadline of occurrence of neutropenia was of 14.6 days. A documentation of the fever is obtained clinically at 20 % of the cases, while in 80 % of the cases, the fever remains unknown origin. The infectious sites found are: a) Skin (6.6%), digestive (4.4%), respiratory (8.8%). b) The average duration of the neutropenia was of 18.8 days. Upon completing this work, we emphasize the need of prompt and appropriate management of the hematological emergency that is febrile neutropenia by an adapted empirical antibiotic therapy after a good bacteriological investigation, without forgetting the importance of prophylaxis based mainly on hygienic mucocutaneous measures and the information/education of parents about the risk of infection and means of prevention.

Steppe lemmings and Chinese hamsters as new potential animal models for the study of the Leishmania subgenus Mundinia (Kinetoplastida: Trypanosomatidae).

Leishmania, the dixenous trypanosomatid parasites, are the causative agents of leishmaniasis currently divided into four subgenera: Leishmania, Viannia, Sauroleishmania, and the recently described Mundinia, consisting of six species distributed sporadically all over the world infecting humans and/or animals. These parasites infect various mammalian species and also cause serious human diseases, but their reservoirs are unknown. Thus, adequate laboratory models are needed to enable proper research of Mundinia parasites. In this complex study, we compared experimental infections of five Mundinia species (L. enriettii, L. macropodum, L. chancei, L. orientalis, and four strains of L. martiniquensis) in three rodent species: BALB/c mouse, Chinese hamster (Cricetulus griseus) and steppe lemming (Lagurus lagurus). Culture-derived parasites were inoculated intradermally into the ear pinnae and progress of infection was monitored for 20 weeks, when the tissues and organs of animals were screened for the presence and quantity of Leishmania. Xenodiagnoses with Phlebotomus duboscqi were performed at weeks 5, 10, 15 and 20 post-infection to test the infectiousness of the animals throughout the experiment. BALB/c mice showed no signs of infection and were not infectious to sand flies, while Chinese hamsters and steppe lemmings proved susceptible to all five species of Mundinia tested, showing a wide spectrum of disease signs ranging from asymptomatic to visceral. Mundinia induced significantly higher infection rates in steppe lemmings compared to Chinese hamsters, and consequently steppe lemmings were more infectious to sand flies: In all groups tested, they were infectious from the 5th to the 20th week post infection. In conclusion, we identified two rodent species, Chinese hamster (Cricetulus griseus) and steppe lemming (Lagurus lagurus), as candidates for laboratory models for Mundinia allowing detailed studies of these enigmatic parasites. Furthermore, the long-term survival of all Mundinia species in steppe lemmings and their infectiousness to vectors support the hypothesis that some rodents have the potential to serve as reservoir hosts for Mundinia.

Outcomes Following Different Management of Mycotic Infrarenal Abdominal Aortic Aneurysms.

The objective was to present our experience on managing mycotic infrarenal abdominal aortic aneurysm (MIAAA) through a retrospective cohort study. Data of patients with MIAAA managed in our center from July 2016 to October 2022 were retrospectively analyzed. The diagnosis of MIAAA was made based on: (1) preoperative clinical signs of infection; (2) elevated serologic infection parameters; (3) para-aneurysmal infection features on enhanced computed tomography; and (4) positive blood or tissue cultures. All the patients received standard antibiotic therapy. Surgical management including endovascular aneurysm repair (EVAR), initial EVAR followed by open re-operation, and initial open surgical repair (OSR) were conducted according to disease seriosity, physical condition, and patient's will. Infection index and clinical outcome were evaluated during the follow-up time. A total of 23 patients (21 men; averaged=66.3 years, range=49-79 years) were included, with a mean follow-up time of 19.9 months (range=1-75 months). Bacteria culture from blood or tissue specimen was positive in 15 patients (Salmonella, n=8; Escherichia coli, n=3; methicillin-sensitive Staphylococcus aureus [MSSA], n=1; Klebsiella pneumoniae, n=1; Staphylococcus epidermidis, n=1; Mycobacterium tuberculosis, n=1). Seven patients received OSR as the initial surgical intervention, whereas 14 patients chose EVAR instead. The 2 conservatively managed patients (refused surgery) died within 30 days. The 7 patients who received initial OSR survived till now. Among the 14 patients who underwent initial EVAR, infection deteriorated without exception (14/14, 100%). Three of these patients refused re-operation and died within 6 months. Eleven patients received secondary surgical intervention (10 cases of aneurysm and endograft resection, thorough debridement, subclavian to bi-femoral artery bypass, or in situ aorta reconstruction; 1 case of laparoscopic debridement) and 7 survived the follow-up time. The overall mortality rate was 39.1% (9/23). The mortality rates differed greatly following different intervention methods (merely antibiotic management, 100%; initial open operation, 0%; initial EVAR without secondary operation, 100%; initial EVAR plus secondary operation, 36.4%). Open surgical repair is still the first choice for hemodynamically stable and low-risk patients. Merely EVAR is related with disastrous results, which should be reserved as a temporary alternative for patients with ruptured aneurysms, hemodynamic instability or high surgical risk, and followed by timely secondary OSR. The management of mycotic or primary-infected aortic aneurysm is challenging; treatment remains controversial. Our center has reviewed our experience over the past 6 years and found that open surgical repair is still the first choice for hemodynamically stable and low-risk patients. Merely endovascular aneurysm repair (EVAR) is related with disastrous results, which should be reserved as a temporary alternative for patients with ruptured aneurysms, hemodynamic instability or high surgical risk, and followed by timely secondary open surgical repair.

Molecular genetic determinants of virulence of Streptococcus agalactiae isolated from pregnant women and newborns in St. Petersburg and the Leningrad region in 2010–2023

Introduction. Colonization of the reproductive organs of pregnant women with group B streptococci (GBS; Streptococcus agalactiae) can lead to severe perinatal and neonatal pathology. In modern conditions, aside from the prevention of antenatal infection of the fetus during childbirth using antibacterial drugs, vaccination is also necessary. In this regard, surveillance of GBS genotypes is an important task. Objective. To determine the molecular genetic determinants of virulence of Streptococcus agalactiae isolated from pregnant women and newborns, and to monitor the distribution of capsular polysaccharides types and pili profiles in GBS clinical isolates. Materials and methods. The study used clinical isolates of GBS (n = 420) isolated from pregnant women and newborns in 2010–2023.The bacteriological method was used for isolation of S. agalactiae. PCR method was used to determine the types of capsular polysaccharides, pili, and whether the strains belonged to the hypervirulent sequence type ST-17. Results. During 13 years of observation, the predominance of Ia, III and V genotypes of GBS capsular polysaccharides was noted both in pregnant women and in newborns. The frequency of occurrence of genotype Ib increased from 0.7 to 6.7%, genotype V from 12.1 to 24.4%, and the prevalence of genotype III decreased significantly from 41.1 to 21.1%. Hypervirulent sequence type ST-17 was detected in 6 pregnant women and 2 newborns. However, there were no signs of neonatal infection in these children. More than half of all clinical isolates of S. agalactiae had pili genotypes PI-1 + PI-2a, as well as pili genotypes PI-2a and PI-1 + PI-2b. The distribution of pili types did not change over 13 years of the surveillance period. Conclusion. Surveillance of the GBS capsular polysaccharides and pili genotypes is necessary for the development of effective preventive vaccines.

The use of antibiotics in the early stage of acute exacerbation of chronic obstructive pulmonary disease in patients without obvious signs of infection: a multicenter, randomized, parallel-controlled study.

Chronic obstructive pulmonary disease (COPD) is a chronic respiratory disease with high prevalence and mortality. In some acute exacerbations of COPD (AECOPD) in patients with no obvious signs of infection, early antibiotic treatment seems to clinically improve the disease, but more studies are needed to determine the prognostic impact of antibiotic treatment in AECOPD patients with no obvious signs of infection. To clarify the impact of antibiotic treatment on the short-term and long-term prognoses of AECOPD patients without obvious signs of infection. The impact of the two treatment methods on the prognosis of patients was compared at 30, 90, 180, and 360days after discharge. A multicenter, randomized, parallel-controlled clinical trial was conducted in a department of respiratory and critical care medicine in Central China. All patients met the inclusion criteria for AECOPD, and the patients were randomly assigned to the antibiotic group or the nonantibiotic group at a 1:1 ratio. Patients in the antibiotic group were given moxifloxacin 400mg/day intravenously for 7days. Patients in the nonantibiotic group were intravenously injected with the same amount of normal saline as the amount of moxifloxacin given to those in the antibiotic group for 7days. There were 406 patients in the antibiotic group and 410 patients in the nonantibiotic group. During the short-term and long-term follow-ups, the acute exacerbation frequency, intensive care unit (ICU) treatment rate, mortality, and mMRC and CAT scores were not significantly different between the two groups (p > 0.05). At the 180- and 360-day follow-ups, the forced expiratory volume in 1s (FEV1%) and peak expiratory flow (PEF) were not significantly different between the two groups (p > 0.05). The 30-day readmission rate was significantly lower in the antibiotic group than in the nonantibiotic group (p < 0.05). The time from discharge to the first acute exacerbation was not significantly different between the two groups (p > 0.05). The length of the first hospital stay after discharge was significantly lower in the antibiotic group (5.84days) than in the nonantibiotic group (6.75days) (p < 0.05). At the 30-day follow-up, the acute exacerbation frequency, age, C-reactive protein (CRP) level, and sputum viscosity were significantly greater in the nonantibiotic group than in the antibiotic group (p < 0.05). In addition, according to the receiver operating characteristic (ROC) analysis, the frequency of acute exacerbations at the 30-day follow-up was significantly greater in COPD patients aged >62.5years, with a CRP level >12.56mg/L or with a sputum viscosity >III, in the nonantibiotic group than in those in the antibiotic group, suggesting that the short-term prognosis was poor. Patients who are >62.5years of age, have a CRP concentration >12.56mg/L, or have a sputum viscosity >III without obvious signs of infection should be treated with antibiotics to improve their short-term prognosis. (https://www.chictr.org.cn), (ChiCTR1800018921).

Antibiotic prophylaxis may effectively reduce early failures after beginner-conducted dental implant surgery.

A randomized, double-blind, placebo-controlled clinical trial. To assess the impact of antibiotic prophylaxis on postoperative recovery and implant short-term survival in clinically healthy patients who underwent placement of 2-4 dental implants by inexperienced operators. The study adhered to the ethical guidelines of theHelsinki declaration, and followed the CONSORT protocol for randomized controlled trials (RCTs). Signed consent forms were provided by all patients. Included were healthy individuals aged over 18 years, with sufficient and fully healed alveolar ridge (undergone extraction at least 3 months prior), requiring placement of 2-4 dental implants, and were classified as ASA I or II. Exclusion criteria were: systemic diseases, hypersensitivity to penicillin, pregnancy or lactation, smoking, recent antibiotic usage, and history of periodontitis. Patients were randomly allocated into 2 groups: the antibiotic group received 1 g of amoxicillin one hour before surgery, while the placebo group was given starch-filled capsules that looked identical to the antibiotic. All implants were installed through 2-stage procedures by students of a specialization course in implant surgery, employing a standardized procedure and armamentarium. Each patient was evaluated preoperatively, and at 2 days and 7 days postoperatively, for the following parameters: mouth opening, experienced pain (using a visual analog scale), and signs of infection (fistula, wound ulceration, tissue necrosis, flap dehiscence, and purulent exudates). Implant survival was monitored for up to 90 days after implant surgery. A total of 90 patients (224 implants) were included: 43 patients (108 implants) in the antibiotic group, and 47 patients (116 implants) in the placebo group. Overall, there were 58 women and 32 men, aged from 23 to 70 years old. In terms of mouth opening, pain, and infection parameters, no statistically significant differences were observed between the groups at any of the time points evaluated. Similarly, there was no statistically significant difference regarding antibiotic usage and implant loss at the patient level (p = 0.06). However, at the implant level, significantly higher implant loss rate was noted in the placebo group (14.9%) compared to the antibiotic group (2.3%) [p < 0.05]. Prophylactic antibiotic administration effectively reduced the occurrence of implant loss after implant surgery performed by inexperienced practitioners.

Mid to Long-term Outcomes of Grade III-B Open Tibial Fractures Definitively Managed with a Circular Frame: A 13-Year Prospective Database Study at a Major Trauma Centre.

Objectives: The aim of this study was to report experience of a major trauma centre utilising circular frames as definitive fixation in patients sustaining Gustilo-Anderson (GA) 3B open tibial fractures. Methods: Design: A prospectively maintained database was retrospectively interrogated. Setting: Single major trauma centre in the United Kingdom. Patient Selection Criteria: All patients over the age of 16 sustaining an open tibial fracture with initial debridement performed at the study centre. All patients also received orthoplastic care for a soft tissue defect (via skeletal deformation or a soft tissue cover procedure) and subsequent definitive management using an Ilizarov ring fixator. Patients who received primary debridement at another centre, had pre-existing infection, sustained a periarticular fracture or those who did not afford a minimum of 12-months follow-up were excluded. Case notes and radiographs were reviewed to collate patient demographics and injury factors. Outcome Measures and Comparisons: The primary outcome of interest was deep infection rate with secondary outcomes including time to union and secondary interventions. Results: 225 patients met inclusion criteria. Mean age was 43.2 years old, with 72% males, 34% smokers and 3% diabetics. Total duration of frame management averaged 6.4 months (SD 7.7). 8 (3.5%) patients developed a deep infection and 41 (20%) exhibited signs of a pin site infection. 79 (35.1%) patients had a secondary intervention of which; 8 comprised debridement of deep infection, 29 bony procedures, 8 soft tissue operations, 30 frame adjustments and 4 patients requiring a combination of soft tissue and bony procedures. Bony union was achieved in 221 cases (98.2%), 195 (86.7%) achieved union in a single frame without the need for secondary intervention, 26 required frame adjustments to achieve union. Autologous bone grafts were used in 10 cases. Conclusions: Orthoplastic care including circular frame fixation for GA-3B fractures of the tibia resulted in a low rate of deep infection (3.5%) and achieved excellent union rates (98.2%). Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

PSIII-6 Tail damage caused by tail biting in growing-finishing pigs housed in two group sizes

Abstract Tail biting can compromise the welfare of pigs and cause economic losses for pork producers, but little is known about the development of tail biting and its resulting impact on pigs. In this study, we investigated victimization by tail biting and the resulting impacts on the welfare and performance of pigs housed in two group sizes. Pigs (n = 432, initial body weight = 22.0 ± 3.7 kg) with intact tails were housed in large (LG = 18 pigs/pen, 12 pens) or small groups (SG = 9 pigs/pen, 24 pens) in a barn with fully slatted floors for 14 wk until market weight (120.7 ± 11.8 kg). Floor space (0.76 m2/pig) and feeder space (4 feeder spaces/9 pigs) allowance were identical between group sizes, and pigs were stratified by initial body weight and sex across treatment pens. Growth performance, pig removal, and tail damage were monitored throughout the study. Tail damage was assessed for each pig weekly and during tail biting outbreaks, using a subjective scoring system (0 = no damage; 1 = healed lesions with small scabs; 2 = puncture wounds with visible blood; 3 = wounds with signs of infection; 4 = partial or total loss of the tail). The maximal tail score (MTS) each pig received every four weeks and over the entire 14 weeks was summarized. Pigs that received MTS of ≥ 2 were considered victimized by a tail biter. Data were analyzed using Glimmix procedure with logit function and FREQ procedure with chi-square and CMH test of SAS software. Compared with SG, LG had greater MTS during the initial 4 wk (1.1 vs. 0.8, chi-square = 17.9, df = 1; P &amp;lt; 0.001) and reduced MTS during the last 2 wk (0.7 vs. 0.9, chi-square = 4.8, df = 1; P = 0.03), suggesting that tail damage declined as pigs grew in LG, but not in SG. The number of pigs removed for tail biting tended to be less and those removed for death and sickness tended to be greater in LG than in SG (chi-square = 7.4; df = 3; P = 0.06). Across group sizes, 68% of the removed pigs (n = 28) were victimized by tail biters (MTS ≥ 2). Between group sizes, there was no difference in time to first victimization or how often individual pigs were victimized throughout the study. Across group sizes, 45% of pigs were never victimized, but 22%, 16%, and 9% were victimized 1, 2, and 3 times, respectively. Eight percent of pigs were victimized more than three times, including 6% with MTS of 3 or 4. Pigs with MTS of 4 over the entire study period were three times more likely (odds ratios between 3.18 and 3.70; all P ≤ 0.03; Table 1) to have market weight lower than the average compared with other pigs. Based on these results, we suggest that management strategies should prevent multiple victimizations or tail loss to maintain pig welfare and performance.

209 Influence of litter origin on performance and tail biting in growing-finishing pigs

Abstract Tail biting is a multifactorial phenomenon with many aspects contributing to a tail biting outbreak. Little is known about how social structures influence tail biting. Our objective was to determine if litter origin impacts growth performance and tail damage caused by biting behaviors of undocked growing-finishing pigs. Pigs were separated based on their litter origin. Three treatments (12 pens/treatment) were tested: LM = all littermates (all 7 pigs/pen were farrowed and nursed by the same sow), N = non-littermates (7 pigs/pen were farrowed and nursed by 7 different sows), and H = half-group of littermates (7 pigs/pen were farrowed and nursed by 2 sows with 3 or 4 of pigs from each sow). The study was conducted in 2 replications (6 pensּ treatment-1ּ replication-1). Within each replication growth performance, mortality, and morbidity were recorded for 12 wk until pigs reached market weight. Tail damage was evaluated using a subjective scoring system: 0 = no evidence of tail biting; 1 = evidence of chewing without visible blood; 2 = evidence of tail biting with visible blood; 3 = open wounds or abscesses with signs of infection; and 4 = partial or total loss of the tail. Tail damage was assessed weekly during the study period, and the maximal tail score (MTS) that each pig received over the entire 12 wk was recorded. The number of pigs removed and the reason for removal was recorded. Data were analyzed using the mixed procedure of SAS for performance variables with a statistical model including treatment, week, and their interaction as fixed effects, replication as a random effect, and initial body weight as a covariate. A frequency procedure with a chi-square (CMH) tested treatment effects on pigs removed and MTS. Litter origin did not affect average daily feed intake (ADFI), gain to feed ratio (G:F), or pigs removed from each treatment group (all P &amp;gt; 0.19; Table 1), but average daily gain (ADG) of H pigs tended to be greater than that of LM pigs (P = 0.07). Maximal tail score was influenced (P = 0.008) by litter origin treatments. Pigs in LM groups had a greater percentage of MTS 0 compared with H and N groups; and H had greater severity of tail damage with 16.7% of the pigs having an MTS of 3 or greater, while both LM and N had less than 5%. Results of this study suggest that litter origin can influence severity of tail damage caused by tail biting behaviors as indicated by MTS. Future studies should focus on the differences among litter origin treatment groups regarding social interactions to further understand how social structure influences tail biting behaviors.

197 Effects of dietary zinc supplementation strategy on immune response, bacterial load and disease severity in growing gilts infected with Mycoplasma hyopneumoniae.

Abstract The objective of this study was to assess impacts of dietary zinc (Zn) supplementation strategy on immune response, bacterial clearance, and disease severity in growing gilts infected with Mycoplasma hyopneumoniae. Weaned gilts [n = 96; 21-d old; initial body weight (BW) = 6.94 kg], were used in a 63-d experiment which consisted of a pre- (d 0-35) and post- (d 35-63) M. hyopneumoniae challenge. On d 0 (-35 d post-inoculation; dpi), gilts were confirmed negative for M. hyopneumoniae and PRRSv and assigned randomly to 1 of 2 dietary treatments with 8 pens/treatment and 6 gilts/pen. Treatments were: 1) Control; 125 mg/kg Zn from ZnSO4, and 2) Zn-blend; 125 mg/kg Zn with 50 mg/kg Zn from Zn-amino acid complex (ZnAA) and 75 mg/kg Zn from ZnSO4. Dietary treatments were fed in 4-phases with pharmacological levels of zinc oxide included in the first 2 phases. Phase 1 (d 0) control and Zn-blend diets contained 3,121 and 3,256 mg/kg total Zn, respectively. Phase 2 (d 0-14) control and Zn-blend diets contained 3,657 and 3,593 mg/kg total Zn, respectively. Phases 3 (d 14-35) and 4 (d 35-63) control and Zn-blend diets contained 213 and 193 mg/kg and 229 and 212 mg/kg total Zn, respectively. At 0 and 1 dpi, all gilts were inoculated intratracheally with 10 mL of a lung homogenate containing 1×105 CCU/mL of M. hyopneumoniae strain 232. Blood and tracheal secretions were collected on -35, 0, 7, 14, 21, 28 dpi. Blood samples were evaluated for antibody detection, and tracheal secretions were analyzed by PCR. Number of coughs were recorded daily from 7 to 28 dpi. At 28 dpi, gilts were humanely euthanized, and bronchoalveolar lavage fluid (BALF) and macroscopic lung lesion observations were collected. Gross lung lesions were scored, and lung tissues were fixed for histopathology. Normally distributed data were analyzed in a generalized linear model with the fixed effect of diet and repeated measures for days post-inoculation. Non-normal data were analyzed using a Mann Whitney U Test using the NPAR1WAY procedure of SAS with a fixed effect of diet or a Chi-square test. Gilts consuming control diets tended (21.68 vs. 20.90 Ct, P = 0.08) to have less relative bacterial load than those consuming Zn-blend diets, over time. No differences in mean sample-to-positive ratio or proportion of gilt seroconversion (P &amp;gt; 0.05) were detected between treatments. There were no differences in mean concentrations of IL-1α, IL-1β, IL-6, IL-8, IL-10 (P &amp;gt; 0.05) in BALF for gilts consuming control or Zn-blend diets. There were no differences in mean macroscopic (P = 0.73) or microscopic (P = 0.67) lung scores, and coughing index score (P = 0.25) over the entire period between gilts consuming the different dietary Zn supplementation strategies. In conclusion, growing gilts consuming diets containing different Zn sources exhibited similar signs of infection during the acute phase of a M. hyopneumoniae infection.