Primary Abscess Research Articles

Primary spinal epidural abscess: magnetic resonance imaging characteristics and diagnosis

Rationale and objectiveTo investigate the MR characteristics of phlegmonous stage and abscess stage primary spinal epidural abscess.Materials and methodsThis study retrospectively analyzed the clinical and imaging characteristics of 27 cases of pathologically confirmed primary spinal epidural abscess. Predisposing conditions of all patients were collected. All patients underwent conventional magnetic resonance imaging, while fifteen patients also underwent post-contrast magnetic resonance imaging.ResultsThe initial symptoms included back pain in 25 patients, fever in 18, motor deficit in five, and sensory changes in 13. Underlying diseases included distant site of infection in seven, injection therapy in five, neoplasm in five, chronic inflammatory disease in five, diabetes mellitus in four, alcoholism in three, metabolic disorder in three, hepatopathy in three, and obesity in two. Abscess location was ventral epidural space in 15 patients (55.6%) and dorsal epidural space in 12 (44.4%). On T1-weighted image, the abscess was hypointense to the spinal cord in 23 patients (85%) and isointense in four (15%). All abscesses were hyperintense to the spinal cord on T2-weighted image. Among the 15 patients who underwent contrast-enhanced imaging, ring enhancement was present in 13 and homogeneous enhancement in two. Adjacent vertebrae body edema was present in four patients. The abscess was purely intraspinal in 25 patients (92.6%). Paraspinal extension was present in two (7.4%).ConclusionPrimary spinal epidural abscess patients have one or more predisposing conditions. Phlegmonous stage primary spinal epidural abscess appears isointense on T1WI and hyperintense on T2WI and enhancement is homogeneous. Abscess stage primary spinal epidural abscess hyperintense on T2WI and hypointense on T1WI and ring enhancement. Presence of vertebral body edema is an important sign to help diagnose primary spinal epidural abscess.

Necrotic lung tumor mimicking primary pulmonary abscess on computed tomographic imaging study in a dyspneic dog

Necrotic lung tumor mimicking primary pulmonary abscess on computed tomographic imaging study in a dyspneic dog

Profiles of primary brain abscesses and their impact on survival: An international ID-IRI study

ObjectivesThis study of 331 primary brain abscess (PBA) patients aimed to understand infecting agents, predisposing factors, and outcomes, with a focus on factors affecting mortality. MethodsData were collected from 39 centers across 16 countries between January 2010 and December 2022, and clinical, radiological, and microbiological findings, along with their impact on mortality, were analyzed. ResultsThe patients had a mean ± SD age of 46.8 ± 16.3 years, with a male predominance of 71.6%. Common symptoms included headache (77.9%), fever (54.4%), and focal neurological deficits (53.5%). Gram-positive cocci were the predominant pathogens, with Viridans group streptococci identified as the most frequently isolated organisms. All patients received antimicrobial therapy and 71.6% underwent interventional therapies. The 42-day and 180-day survival rates were 91.9% and 86.1%, respectively. Significant predictors of 42-day mortality included intravenous drug addiction (HR: 6.02, 95% CI: 1.38-26.26), malignancy (HR: 3.61, 95% CI: 1.23-10.58), confusion (HR: 2.65, 95% CI: 1.19-5.88), and unidentified bacteria (HR: 4.68, 95% CI: 1.76-12.43). Significant predictors of 180-day mortality included malignancy (HR: 2.70, 95% CI: 1.07-6.81), confusion (HR: 2.14, 95% CI: 1.11-4.15), temporal lobe involvement (HR: 2.10, 95% CI: 1.08-4.08), and unidentified bacteria (HR: 3.02, 95% CI: 1.49-6.15). ConclusionThe risk of death in PBA extends beyond the infection phase, with different factors influencing the 42-day and 180-day mortality rates. Intravenous drug addiction was associated with early mortality, while temporal lobe involvement was associated with late mortality.

Double trouble: an unusual case of Klebsiella pneumoniae invasive syndrome with liver abscess, gallbladder empyema and infective endocarditis

BackgroundKlebsiella pneumoniae invasive syndrome (KPIS) is characterized by primary pyogenic liver abscess associated with metastatic infections. Although rare, Klebsiella endocarditis carries a high mortality risk.Case presentationA 60-year-old lady with type II diabetes mellitus presented with fever, malaise, right hypochondriac pain and vomiting for two weeks. Ultrasound abdomen revealed a collection within liver, and distended gallbladder with echogenic debris within. 3 days after ultrasound guided pigtail drainage of gallbladder empyema, newly presence murmur detected. Pus, urine, and blood cultures obtained were positive for Klebsiella pneumonia. Echocardiogram exhibited oscillating mass attached to anterior mitral valve leaflet. After 6 weeks of intravenous ceftriaxone, follow-up echocardiogram and ultrasound showed complete resolution of mitral valve vegetation, hepatic and gallbladder collection.ConclusionConcomitant extrahepatic infective endocarditis (IE) should raise concerns in daily practice for patients with Klebsiella pneumoniae liver abscesses, despite the rarity of Klebsiella endocarditis. In the absence of diagnostic suspicion, antibiotic treatment regimens may be shortened, and adverse effects from IE infection may ensue.

Nontubercular Primary Spinal Epidural Abscess – A Retrospective Study of 11 Culture-Positive Cases

Abstract Background: An epidural abscess that occurs in the absence of contiguous spread from vertebral osteomyelitis or following spinal surgery, spinal anesthesia, or open spinal injuries is considered to be a primary spinal epidural abscess (SEA). The triad of back pain, fever, and progressive neurological dysfunction has long been considered to be the hallmark of primary SEA. Objective: The vast majority of epidural abscesses in our country are either tubercular or associated with pyogenic spondylitis. Primary non tubercular spinal epidural abscesses are rare and also need a different paradigm of management in terms of need for stabilization and duration of antibiotic treatment that we wish to highlight. Material and Methods: Eleven consecutive cases of nontubercular primary SEA were operated by the corresponding author between 2010 and 2019. Their clinical presentation, magnetic resonance imaging (MRI) findings, blood investigations, bacteriological profile, and outcomes were extracted from the patient files and follow-up visits to the outpatient clinic and analyzed 5 years after the last case. Results: All patients had spinal pain at presentation. Seven patients had fever and ten had neurological deficits at presentation. Diabetes and renal failure were the most common comorbidities. All patients had elevated erythrocyte sedimentation rate and C-reactive protein at presentation. The total leukocyte count was not uniformly elevated. One patient who was human immunodeficiency virus positive with a low cell count could not be operated. Diagnosis in his case was established by computed tomography-guided aspirate of the pus. Of the remainder, one patient had no recovery following surgery and two patients had residual deficits. Gram-positive coverage was started empirically in all patients who were operated and based on cultures changed and later extended orally for 4 weeks after discharge till repeat MRI and blood cultures were satisfactory. Conclusions: SEA is a surgical emergency. The majority of cases are caused by Gram-positive bacteria, and many of the patients have comorbidities that need to be addressed. Patients with better preoperative neurological status and those with lumbar location of abscess tend to have a better recovery. Antibiotic treatment must be continued till postoperative radiological and hematological parameters are satisfactory.

Primary abscess of the sella turcica of odontogenic nature (observation from practice)

Abscess of the sella turcica is an extremely rare disease of the chiasm and sellar region which often clinically and radiologically imitates other lesions in this area complicating the diagnosis.The article presents a clinical case of a 42‑year‑old female patient with primary abscess of the sella turcica which at first was considered to be pituitary adenoma. The patient underwent surgery through endoscopic transnasal access with good postoperative outcome. Additional postoperative examination revealed a possible source of hematogenic advancement of infectious process into the sella turcica cavity – pericoronitis of tooth 4.8. The article also presents review of publications on the topic.

Comparison of surgical outcomes between primary and secondary brain abscess.

Brain abscess (BA) constitutes 1-8% of intra-cerebral tumors, and thus the present study aimed to compare the surgical outcomes of patients with primary and secondary BA. The present retrospective study examined 32 of cases BA who underwent surgery in a local institution between February, 2013 and December, 2023. All patients received intravenous antibiotic therapy according to the antibiogram for antimicrobial susceptibility. In total, 32 patients were separated into two groups as follows: Group A (16 patients, 50%) with primary abscess and group B (16 patients, 50%) with secondary abscess. Of the 32 patients included in the study, 23 (71.8%) were males, and the median age was 55.3 years. On the whole, the present study demonstrates that a multidisciplinary approach involving a combination of often multiple surgical procedures and prolonged antibiotic medication may improve the functional outcome if the underlying pathology allows for a functional outcome.

Antibiotic Treatment Has No Influence on Anal Fistula Formation and Recurrent Perianal Abscess After Incision and Drainage of Cryptogenic Perianal Abscess: A Randomized Single-Blinded Prospective Study.

Anal fistula commonly appears after incision and drainage of a perianal abscess. Theoretically, a fistula develops as a consequence of the infection process. Antibiotic treatment was suggested to decrease the possibility of fistula development. We hypothesized that antibiotic treatment has no influence on the development of anal fistula after surgical treatment of perianal abscess. A single-blinded randomized prospective study. Patients with primary cryptogenic abscesses were eligible to participate. Patients were divided into 2 groups. Patients in group I received amoxicillin 875 mg/clavulanic acid 125 mg during 7 days after surgery, and patients in group II received no antibiotics. The study database included demographics and clinical and laboratory data. Patients were examined in our outpatient clinic 2 weeks, 4 months, and 1 year after surgery, and a telephone questionnaire was performed 6 months after surgery. The primary outcome was the formation of anal fistula. The secondary outcome was recurrent perianal abscess. Overall, 98 patients completed the study. Groups were not different in inclusion. Anal fistula was diagnosed in 16 patients (16.3%) in group I (treatment group) and 10 patients (10.2%) in group II (control group; p = 0.67). Nine patients (9.2%) developed recurrent perianal abscess, 4 in the treatment group and 5 in the control group ( p = 0.73). A relatively small number of patients were treated in a single medical center. Antibiotic therapy has no influence on anal fistula or recurrent perianal abscess formation after incision and drainage of perianal abscess. See Video Abstract . ANTECEDENTES:La fístula anal comúnmente aparece después de la incisión y drenaje de un absceso perianal. Teóricamente, la fístula se desarrolla como consecuencia del proceso infeccioso. Se sugirió tratamiento antibiótico para disminuir la posibilidad de desarrollo de fístula.OBJETIVO:Hipotetizamos que el tratamiento con antibióticos no tiene influencia en el desarrollo de fístula anal después del tratamiento quirúrgico del absceso perianal.DISEÑO:Estudio prospectivo, aleatorio, simple ciego.AJUSTE Y PACIENTES:Los pacientes con absceso criptogénico primario fueron elegibles para participar. Los pacientes se dividieron en dos grupos. Los pacientes del Grupo I recibieron amoxicilina 875 mg/ácido clavulánico 125 mg durante los 7 días posteriores a la cirugía y los pacientes del Grupo II no recibieron antibióticos. La base de datos del estudio incluyó datos demográficos, clínicos y de laboratorio.PRINCIPALES MEDIDAS DE RESULTADO:Los pacientes fueron examinados en nuestra clínica ambulatoria 2 semanas, cuatro meses y 1 año después de la cirugía y se realizó un cuestionario telefónico 6 meses después de la cirugía. El resultado primario fue la formación de una fístula anal. El resultado secundario fue el absceso perianal recurrente.RESULTADOS:En total, 98 pacientes completaron el estudio. Los grupos no fueron diferentes en cuanto a la inclusión. Se diagnosticó fístula anal en 16 (16,3%) pacientes del Grupo I (grupo de tratamiento) y 10 (10,2%) pacientes del Grupo II (grupo control) (p = 0,67). Nueve pacientes (9,2%) desarrollaron absceso perianal recurrente, 4 en el grupo de tratamiento y 5 en el grupo control (p = 0,73).LIMITACIONES:Número relativamente pequeño de pacientes tratados en un solo centro médico.CONCLUSIÓN:La terapia con antibióticos no tuvo influencia sobre la fístula anal o la formación de absceso perianal recurrente después de la incisión y drenaje del absceso perianal. (Traducción - Dr. Fidel Ruiz Healy ).

Percutaneous Drainage of Pediatric Pulmonary Abscesses: An Effective Therapy

IntroductionPulmonary abscess is a complication of lung infection with localized necrosis and purulent cavity formation. Pulmonary abscesses are typically managed using antibiotic therapy with anatomic surgical resection reserved as a rescue. Percutaneous drainage is considered relatively contraindicated in some centers due to perceived risk of bronchopleural fistula. However, drain placement has been frequently employed at our institution. The purpose of this study was to review and describe our longitudinal experience. MethodsMedical records of children diagnosed with lung abscess and treated with percutaneous drainage from 2005 through 2023 were reviewed. Patient clinical parameters, follow-up imaging, and clinical outcomes were evaluated. ResultsPercutaneous drainage (n = 24) or aspiration alone (n = 4) under imaging guidance was performed by interventional radiologists for 28 children with lung abscesses. A single catheter (8–12 Fr) was deployed in the pulmonary abscess cavity and remained for a median of 6 days (IQR: 6–8 days). The median hospital stay was 10 days (IQR: 8.8–14.8 days). The technical success rate for percutaneous drainage or aspiration of primary pulmonary abscesses was 100% (26/26). Two children were later diagnosed with secondarily infected congenital pulmonary airway malformations that were both successfully drained and ultimately surgically resected. The abscess cavities resolved in all patients and catheters were removed upon clinical, radiographic, and laboratory improvement. Complications included the presence of two bronchopleural fistula, both of which were treated with immediate pleural drain placement. ConclusionPercutaneous drainage of pulmonary abscesses is an effective therapeutic option in children and can be considered alongside antibiotics as part of the initial treatment for pulmonary abscesses. Bronchopleural fistula can occur, but at a lower frequency than previously reported. Level of EvidenceLevel V.

AB156. SOH24AB_273. Primary splenic abscess in an immunocompetent adult female patient: a case report

AB156. SOH24AB_273. Primary splenic abscess in an immunocompetent adult female patient: a case report

Bacteriological characteristics of primary breast abscesses in patients from the community in the era of microbial resistance.

The aim of this study is to evaluate the etiological profile and antimicrobial resistance in breast abscess cultures from patients from the community, treated at a public hospital located in Porto Alegre, Brazil. This is an retrospective cross-sectional study that evaluated the medical records of patients with bacterial isolates in breast abscess secretion cultures and their antibiograms, from January 2010 to August 2022. Based on 129 positive cultures from women from the community diagnosed with breast abscesses and treated at Fêmina Hospital, 99 (76.7%) of the patients had positive cultures for Staphylococcus sp, 91 (92%) of which were cases of Staphylococcus aureus. Regarding the resistance profile of S. aureus, 32% of the strains were resistant to clindamycin, 26% to oxacillin and 5% to trimethoprim-sulfamethoxazole. The antimicrobials vancomycin, linezolid and tigecycline did not show resistance for S. aureus. Staphylococcus aureus was the most common pathogen found in the breast abscess isolates during the study period. Oxacillin remains a good option for hospitalized patients. The use of sulfamethoxazole plus trimethoprim should be considered as a good option for use at home, due to its low bacterial resistance, effectiveness and low cost.

Beyond the norm: A case report on the unfolding spectrum of acute suppurative thyroiditis leading to abscess formation

The thyroid gland’s robust defenses, including a rich blood supply, lymphatic drainage, high iodine content, and physical isolation, typically render it resistant to infections. However, acute suppurative thyroiditis (AST) leading to a primary thyroid abscess is an uncommon occurrence, especially among children, accounting for only 0.1–0.7% of thyroid disorders. This case report outlines the clinical presentation of a 12-year-old male with prolonged fever, neck pain, sore throat, and swallowing difficulties. Staphylococcus aureus was identified as the causative agent. Treatment involved a combination of intravenous antibiotics and incision and drainage, resulting in a successful recovery. Despite its rarity, AST requires prompt recognition and intervention to prevent complications. This case emphasizes the significance of including AST in the differential diagnosis of neck swelling and underscores the necessity for early identification and appropriate management to ensure optimal patient outcomes.

Primary splenic abscess in an adult female patient: a case report

BackgroundPrimary splenic abscess is rare and typically presents in patients who are immunocompromised. We present a case of a 47-year-old apparently immunocompetent female patient who was diagnosed with primary splenic abscess from a Salmonella Typhimurium infection following emergency laparotomy.Case presentationA 47-year-old female patient presented with subjective fever and severe epigastric and left flank pain. She was treated empirically with intravenous piperacillin/tazobactam and gentamicin and was resuscitated with intravenous crystalloid infusion. A radiological diagnosis of splenic infarct secondary to splenic artery aneurysm superimposed with splenic abscess was presumed, however at emergency laparotomy, primary splenic abscess was identified. This abscess had eroded the left hemidiaphragm and had ruptured the splenic capsule leading to intra-abdominal pus in the pelvis which on culture grew Salmonella Typhimurium. A splenectomy and primary repair of the left hemidiaphragm were performed, with postoperative pancreatitis diagnosed following the procedure. After intensive care treatment, this patient made a full recovery.ConclusionThis case of primary splenic abscess was treated successfully with a combination of surgery (i.e.: splenectomy and surgical drainage), prolonged antimicrobial therapy, and intensive care in the perioperative period.

WITHDRAWN: Clinical observation of 19 primary pituitary abscess cases treated by transsphenoidal surgery with or without sella packing

ObjectivePituitary abscess (PA) is a rare disease in the sellar region. This study aimed to investigate a series of PA cases with two different approaches to better understand the surgical principles and underlying mechanisms. Methods19 cases of primary PA were included for a comprehensive evaluation with special attention paid to the surgical approaches and the effectiveness and safety with or without sella packing. ResultsHeadache, and visual impairment were the most frequently seen symptoms among all patients. More than half of patients exhibited anterior pituitary dysfunction including panhypopituitarism, with a considerable portion of patients found with elevated prolactin (PRL) along with a thicker stalk on MRI. 11 patients underwent transsphenoidal surgery (TSS) without sella packing for allowing continuous drainage (Non-packing group), while the remaining 8 were operated with fat-based packing following intraoperative pus irrigation (Packing group). Both groups had similarly good outcomes including the duration of antibiotics use, complications, and hospital stay, but the incidence of abscess recurrence was higher for the packing group. ConclusionTSS without sella-packing exhibited comparable safety to the packing approach for PA and may be associated with a lower incidence of recurrence, provided that cerebrospinal fluid (CSF) leakage is well prevented.

Magnetic resonance imaging-derived relative cerebral blood volume characteristics in a case of pathologically confirmed neurocysticercosis: illustrative case.

Neurocysticercosis (NCC) is a parasitic infection of the brain caused by ingesting water or food contaminated with tapeworm eggs. When it presents as a solitary mass, differentiation from a primary brain tumor on imaging can be difficult. Magnetic resonance imaging (MRI)-derived relative cerebral blood volume (rCBV) is a newer imaging technique used to identify areas of neovascularization in tumors, which may advance the differential diagnosis. A 25-year-old male presented after a seizure. Computed tomography (CT) and MRI demonstrated a partially enhancing lesion with microcalcifications and vasogenic edema. Follow-up rCBV assessment demonstrated mild hyperperfusion and/or small vessels at the lesional margins consistent with either an intermediate grade glioma or infection. Given the radiological equipoise, surgical accessibility, and differential diagnosis including primary neoplasm, metastatic disease, NCC, and abscess, resection was pursued. The calcified mass was excised en bloc and was confirmed as larval-stage NCC. CT or MRI may not always provide sufficient information to distinguish NCC from brain tumors. Although reports have suggested that rCBV may aid in identifying NCC, here the authors describe a case of pathologically confirmed NCC in which preoperative, qualitative, standardized rCBV findings raised concern for a primary neoplasm. This case documents the first standardized rCBV values reported in a pathologically confirmed case of NCC in the United States.

Sinus pilonidalis—elastic ligature as an optimal outpatient treatment

Abstract Background The incidence of pilonidal sinus shows a steadily rising tendency, especially in the patient age group of up to 40 years. Treatment of this condition is often protracted involving lengthy sick leave and an increased risk of recurrence. The optimal treatment of pilonidal sinus remains open to debate, but it should focus on decreasing the length of hospitalization, promoting a rapid return to daily life, maintaining low pain levels, and keeping costs at a minimum. Materials and methods In our study conducted between 2017 and 2021, we focused on treatment of pilonidal sinus. We performed 50 elastic ligature procedures with a median observation time of 30 months. The patients were divided into three groups according to the characteristics of pilonidal sinus: (1) acute primary abscess; (2) acute recurrent abscess; and (3) chronic fistula. Results Out of a total of 50 patients with a subsequent 30-month follow-up, we observed complete recovery in 47 patients and recurrence in three patients. Return to work was possible immediately after the operation, with an average total treatment time of 1 month for complete healing of the defect. Conclusion The current results suggest that the technique of elastic ligature is a desirable solution for pilonidal sinus, because of the initial low costs, no need for hospitalization, and good patient tolerance.

Splenic abscess with spontaneous gastrosplenic fistula: case report and review of the literature

Abstract Gastrosplenic fistula (GSF) is an unusual event that might occur in patients with various gastric or splenic diseases. While GSF related to gastric and splenic malignancies is well-documented in the literature, cases of GSF due to a splenic abscess are extremely rare. We experienced the case of a 49-year-old man with a medical history of tricuspid cardiac valve replacement for infective endocarditis who presented with a sudden onset of anemia and melena. With the assistance of imaging and endoscopy, a primary splenic abscess complicated by spontaneous GSF was diagnosed. A prompt splenectomy with partial gastrectomy was performed. GSF is a serious occurrence associated with a high risk of morbidity and mortality. The early recognition of GSF related to a splenic abscess is crucial to prevent major complications. Surgical resection with splenectomy and partial gastrectomy is frequently preferred for the treatment of large abscesses with GSF.

Involvement of Tn3 transposon in formation and transmission of hypervirulent and carbapenem-resistant Klebsiella pneumoniae

ABSTRACT Hypervirulent and carbapenem-resistant Klebsiella pneumoniae poses a severe threat to public health for its high pathogenicity, transmissibility, and drug resistance. This study aims to explore the evolutionary path and the role of Tn3 transposon in the virulence and carbapenem resistance transmission of K. pneumoniae . Bioinformatics analysis and some experimental tests such as plasmid conjugation experiments, antimicrobial susceptibility testing, and virulence-associated tests were performed to explore the virulence and drug resistance transmission. The complete genome sequencing, S1 nuclease pulsed-field gel electrophoresis, and bioinformatics analysis were used to investigate their transmission mechanism mediated by Tn3 transposons. Three hypervirulent and carbapenem-resistant K. pneumoniae isolates, which were obtained from different patients at different time points in the same ward, harbored a virulence plasmid and a carbapenem resistance plasmid. They were confirmed to have first evolved from hypervirulent isolates and then acquired a bla KPC -positive plasmid (CR-hvKp evolutionary pattern). The non-conjugative virulence plasmid pVir could be transferred to other bacterial strains via mobilization by the conjugative IncN/U-type plasmid pKPC, as well as by fusing with the conjugative pKPC plasmid (mediated by Tn3-based homologous recombination) to be self-transmissible, thus transferring drug resistance and virulence. The cointegration, pVir/KPC fusion plasmid, was further resolved into pVir and pKPC between the duplicated copies of the Tn3 transposon resolution site mediated by site-specific recombination. Therefore, Tn3 transposons can mediate hypervirulent and carbapenem-resistant K. pneumoniae strains transferring drug resistance and virulence to other bacteria. We must be vigilant to emerging transposon-mediated hypervirulent and carbapenem-resistant pathogens. IMPORTANCE Carbapenem-resistant Klebsiella pneumoniae (CRKP) is resistant to most common antibiotics, becoming the most important and prevalent nosocomial opportunity pathogen. Besides, K. pneumoniae can also cause severe community-acquired infections, such as primary liver abscess and endophthalmitis. These pathogens are commonly referred to as hvKp. CRKP and hvKp have evolved separately, each occupying its own clonal lineage and exhibiting a variety of properties. Our study provides important insights into the evolutionary events related to the arousal of virulence and drug resistance in K. pneumoniae through plasmid transmission, mediated by Tn3 transposon. Our study also provides evidence that multiple mechanisms contribute to the successful transfer of non-conjugative virulence plasmid, and the involvement of transposons enhances the efficiency. A good knowledge of its transmission mechanisms is fundamental to finding effective strategies to combat these threatening pathogens. Transposons are widely present in bacteria, spreading resistance and virulence genes between the environment and humans. Therefore, emerging transposon-mediated hypervirulent and carbapenem-resistant pathogens should be highly valued.

Comparison of clinical and microbiological characteristics of community-acquired hypervirulent Klebsiella pneumoniae liver abscess in diabetic and non-diabetic patients.

Invasive infection caused by hypervirulent Klebsiella pneumoniae (HvKP) has been reported worldwide. Most of the patients are community population, related to diabetes mellitus (DM), chronic liver disease and other basic diseases, which prone to systemic migratory infection. In this study, we collected 377 patients with community acquired Klebsiella pneumoniae liver abscess in our hospital from January 2013 to December 2018, 65.8% of whom were male, and 49.6% had DM. Patients with DM are prone to eye and central nervous system (CNS) infection, which need continuous local abscess drainage during treatment. Among them, patients with poor blood glucose control have a higher rate of blood stream infections (BSI). 219 strains of HvKP were obtained, with K1/K2 Serotype accounted for 81.7%. The incidence of BSI in K2 patients was higher than that in K1 patients. The PCR results indicate that the carrying rate of virulence genes (rmpA、areo、kfu、allS、iroN、magA、uge、wcaG) in K1/K2 type strains is significantly higher than that in non K1/K2 type strains. ST23 and ST65 are the most common multilocus sequence typing (MLST), which belong to K1 and K2 Serotype respectively. All of HvKP strains showed high sensitivity to commonly used clinical antibiotics other than ampicillin, with 54.3% of the strains exhibiting high viscosity characteristics. Meanwhile, 35 classic Klebsiella pneumoniae (cKP) strains were collected, and their serum typing is mainly non K1/K2. The carrying rate of virulence genes and viscosity degree in HvKP are significantly higher than those in cKP. Primary liver abscess caused by HvKP is prone to multiple tissue and organ infections, but it shows higher sensitivity to most commonly used antibiotics in clinical practice except for ampicillin. After effective treatment, the overall prognosis of patients is better. This study analyzes the pathogenic characteristics of HvKP and elaborates on the clinical characteristics of patients, which can provide reference for clinical and scientific research work.

An incidental diagnosis of an unusually located echinococcus alveolaris.

Hydatid cyst disease is a zoonotic infection caused by the genus Echinococcus. Hydatid cysts are usually located in the liver or lungs whereas the brain is an unusual location. A 45-year-old male patient was diagnosed with an intracranial mass suggesting a metastasis in the frontal region shown in the cranial computed tomography (CT) scan following a cranial trauma. The histological evaluation revealed an acellular laminated lesion surrounded with reactive changes, compatible with a cuticle. These findings were evaluated in favour of a hydatid cyst caused by Echinococcus multilocularis. Alveolar echinococcosis is a zoonotic disease caused by the genus Echinococcus multilocularis. Hydatid cyst is a common public health issue in the countries where livestock farming is common. Primary or metastatic tumours and abscesses should be considered in the differential diagnosis of hydatid cysts regardless of their location.