Minimally invasive discectomy versus open laminectomy and discectomy for the treatment of cauda equina syndrome: A preliminary study and case series.

Background: Cauda Equina syndrome (CES) is a potentially devastating condition and is treated usually with urgent open surgical decompression of the spinal canal. Currently, the role of minimally invasive discectomy (MID) as an alternative surgical technique for CES is unclear. Objective: The purpose of this study was to compare clinical outcomes following MID and open laminectomy and discectomy for the treatment of CES. Methods: The study cohort included patients that underwent surgery due to CES at our institute. Patients' outcomes included: surgical complications, length of hospitalization, postoperative lower extremity motor score (LEMS), Numerical Rating Scale (NRS) for leg and back pain, Oswestry disability index (ODI), and the EQ-5D health-related quality of life questionnaire. Results: Twelve patients underwent MID and 12 underwent open laminectomy and discectomy. Complications and revisions rates were comparable between the groups. Postoperative urine incontinence and saddle dysesthesia improved in 50% of patients in both groups. LEMS improved from 47.08 ± 5.4 to 49.27 ± 0.9 in the MID group and from 44.46 ± 5.9 to 49.0 ± 1.4 in the open group. Although, leg pain improved in both groups from 8.4 ± 2.4 to 3 ± 2.1 in the MID and from 8.44 ± 3.3 to 3.88 ± 3 in the open group, significant improvement in back pain was found only in the MID group. Final functional scores were similar between groups. Conclusions: Our preliminary results suggest that minimally invasive discectomy is an effective and safe procedure for the treatment of CES when compared to open laminectomy and discectomy. However, MID in these cases should only be considered by surgeons experienced in minimally invasive spine surgery. Further studies with bigger sample sizes and long-term follow-ups are needed.

Histopathological Characteristics of N1b Papillary Thyroid Carcinoma are Associated with Risk of Recurrence.

BACKGROUND: The presence of cervical lymph node (LN) metastasis at the initial presentation of papillary thyroid carcinoma (PTC) constitutes an independent risk factor for disease recurrence, increases the risk for mortality, and impacts overall outcome. The 2016 American Joint Committee on Cancer raised the age cutoff for PTC staging from 45 to 55 years for better prediction of overall survival. Age > 55 years is considered a significant risk factor for a more aggressive and advanced disease with worse outcomes. We identified histopathological factors for disease recurrence in PTC patients younger and older than 55 years of age. METHODS: Data on all patients who underwent thyroid surgery due to PTC between 2006 and 2018 in the Tel Aviv Sourasky Medical Center were retrieved for this retrospective cohort study. Patients with lymph node (LN) metastases were further investigated for preoperative presentation, pathological characteristics, and recurrence. A multivariate analysis was used to detect predictors for recurrence and patient outcome for each age-group. RESULTS: Twenty-two of the 183 patients (12%) with PTC who met the inclusion criteria and had sufficient follow-up period sustained recurrence. The predictors of recurrence varied between the two age-groups. The size of thyroid lesions (p = 0.003) was identified as a risk factor in the older group, while the number of metastatic cervical LNs (p = 0.001) and the ratio of metastatic-to-total dissected cervical LNs (p = 0.027) were the main predictors of recurrence for the younger group. CONCLUSION: The histopathological factors predictive for disease recurrence differed among PTC patients younger and older than 55 years of age.

Correction to: Total thyroidectomy with therapeutic level II-IV neck dissection for papillary thyroid carcinoma: level VI recurrence patterns.

The original article can be found online.

Total thyroidectomy with therapeutic level II-IV neck dissection for papillary thyroid carcinoma: level VI recurrence patterns.

OBJECTIVE: Lateral and central compartments cervical lymph nodes metastases are common among patients with papillary thyroid carcinoma (PTC). Elective level VI neck dissection during thyroidectomy and lateral neck dissection (LND) for the treatment of PTC with lateral compartment lymph node metastases is controversial because of the uncertain benefit in clinical outcomes and increased risks of surgical morbidity. We aimed to determine the potential benefit of elective level VI neck dissection in patients with cN1 papillary thyroid carcinoma (PTC) by investigating the rate and pattern of locoregional recurrence in PTC patients who underwent total thyroidectomy and therapeutic lateral node dissection (LND; levels II-IV) without elective level VI dissection. METHODS: A retrospective cohort study. Data on demographics, clinical presentation and workup, intraoperative and pathological report, postoperative course, adjuvant therapy, recurrence patterns, and overall survival were retrieved from the medical charts of patients who underwent thyroid surgery in our hospital between January 2006 and December 2017. RESULTS: A total of 1415 thyroidectomies were performed during the study period, of which 802 (56.67%) were for PTC. Of those PTC patients, 228 (28.42%) also underwent LND (levels II-VI) during the same thyroidectomy procedure. Thirty-four (14.91%) of those 228 patients, underwent total thyroidectomy with therapeutic lateral ND II-IV without elective level VI ND. During the follow-up period, five (14.7%) of the latter cohort were diagnosed with recurrence in central neck (level VI) lymph nodes, and four of them (11.7%) were diagnosed with ipsilateral recurrence at level VI. CONCLUSION: Our results revealed 11.7% rate of clinically significant recurrent disease in ipsilateral level VI which, in our opinion, does not justify routine prophylactic level VI ND dissection when the ipsilateral lateral neck is operated for metastases.

Novel rat model of methicillin-resistant Staphylococcus aureus-infected silicone breast implants: a study of biofilm pathogenesis.

BACKGROUND: Clinical infection of breast implants occurs in 7 to 24 percent of breast reconstructions. It may persist over time in the form of biofilm without overt manifestation and is extremely difficult to eradicate. The authors' aim was to establish a novel model for biofilm infection of silicone breast implants in rats. METHODS: Fifty-six rats underwent implantation of miniature silicone breast implants and/or methicillin-resistant Staphylococcus aureus (MRSA) bacteria. Group A received implants covered with MRSA biofilm. Group B received implants and free planktonic MRSA. Group C received free planktonic MRSA without implants. A control group received sterile implants without MRSA. Each group was divided to receive either saline or vancomycin injections between days 4 and 11. Clinical evaluation, bacterial counts, and scanning electron microscopy were performed. RESULTS: The mortality rate in group B (implants infected with free planktonic MRSA) was significantly higher than that in all other groups [37 percent versus groups A and D (0 percent) and group C (7 percent)]. Treatment with vancomycin lowered temperature in groups B and C (p < 0.05) and improved wound healing in group B (p < 0.01). Vancomycin treatment reduced wound bacterial counts in free planktonic MRSA groups B and C but had no significant effect on biofilm MRSA-infected group A. CONCLUSIONS: The model successfully induced persistent breast implant infection. Free planktonic MRSA produced in situ biofilm on silicone implants. Biofilm infection has milder manifestations than free planktonic MRSA infection, which has higher rates of systemic infections and death when compared with either isolated biofilm infection or free planktonic MRSA infection without implant. Vancomycin has limited effect against mature biofilm.

Staphylococcus aureus mediastinitis and sternal osteomyelitis following median sternotomy in a rat model.

OBJECTIVES: Median sternotomy (MS) wound infections are severe complications causing high morbidity and mortality after cardiac surgery. We aimed to develop a new Staphylococcus aureus mediastinitis and sternal osteomyelitis model in rats that can be used to evaluate the efficacy of new antimicrobial treatments. METHODS AND RESULTS: A complete MS wound was induced in anaesthetized rats. S. aureus was injected into the sternum. Kinetics of bacterial growth in the sternum (10(7) cfu/sternum) was assessed for histopathology and bacterial counts. A non-infected MS group served as a control. To evaluate antibiotic efficacy, 5 days of intraperitoneal vancomycin therapy (50 mg/kg, twice a day) was initiated 24 h following bacterial challenge. Macroscopic and histological examination confirmed that infection resulted in sternitis and mediastinitis. S. aureus bacterial counts in the sternum were inoculum-dependent, and it was proven that infecting rats with an inoculum of 10(7) cfu/sternum induced mediastinitis and sternal osteomyelitis. At this inoculum, bacterial counts in the infected sternum increased with time, reaching a maximum level of 2 +/- 1 x 10(7) cfu/g of sternum 8-12 days post-infection and then decreased with time to 2 x 10(4) cfu/g of sternum 20 days after infection. Histological changes paralleled bacterial counts. Vancomycin administration showed a protective effect against induction of sternal osteomyelitis; sternums from vancomycin-treated rats showed a significant decrease in S. aureus counts by 0.72 +/- 0.35 log cfu/g compared with untreated controls (P = 0.0162). CONCLUSIONS: This new rat model of S. aureus sternal osteomyelitis and mediastinitis allows quantitative measurement of bacterial counts in the sternum. This model is reproducible and simple and thus suitable for the evaluation of new antimicrobials and new treatment modalities in MS infections.

Efficacy of antibodies against the N-terminal of Pseudomonas aeruginosa flagellin for treating infections in a murine burn wound model.

BACKGROUND: In an era of increasing drug resistance, immunotherapy is a desirable treatment against Pseudomonas aeruginosa infections. The flagellum, which is an important pseudomonal virulence factor, was targeted for immunotherapy. The aim of the study was to evaluate the efficacy of polyclonal immunotherapy targeted against the N-terminal of flagellin (anti-N'-fla-b) for treating severe P. aeruginosa infection in a murine burn wound model. METHODS: Groups of 12 mice were infected (subeschar) with P. aeruginosa strain PA01, and were treated either with systemic anti-N'-fla-b immunoglobulin G (IgG), nonspecific IgG, or imipenem. The control groups included mice with burn alone, mice with untreated infected burn, and mice without burn infected with P. aeruginosa. Three separate regimens were examined: prophylaxis (preinfection), therapeutic (postinfection), and combined. The efficacy of anti-N'-fla-b was evaluated by monitoring the mortality and morbidity (relative weight loss) during a period of 2 weeks. RESULTS: Anti-N'-fla-b IgG immunotherapy significantly decreased the mortality rate of infected burned mice followed by severe P. aeruginosa infection. The mortality rate in the anti-N'-fla-b-treated groups ranged from 0 to 17 percent compared with 58 to 83 percent in nontreated groups infected with 2 to 5 x 10(6) colony-forming units of P. aeruginosa (p < 0.05). The mortality rate in the anti-N'-fla-b-treated groups was similar to that of groups treated with imipenem. The three tested regimens yielded similar results. Morbidity paralleled survival results. Histopathologic examination revealed an earlier reepithelialization of the infected wound in the anti-N'-fla-b-treated mice compared with untreated mice. CONCLUSION: Immunotherapy with anti-N'-fla-b IgG, given either as prophylaxis or therapeutically, effectively reduced mortality and morbidity and improved wound healing in a severely P. aeruginosa-infected murine burn model.

The establishment of a Pseudomonas aeruginosa-infected burn-wound sepsis model and the effect of imipenem treatment.

INTRODUCTION: We present a standardized Pseudomonas aeruginosa (PA) infected burn-wound model in mice for evaluating new antimicrobials and therapy strategies for PA infections and demonstrate the effect of the antibiotic imipenem in this model. METHODS: A 6%-8% total body surface area, full-thickness, scald-burn wound was induced in anesthetized mice. Two study groups (PA-infected burn) were compared with 1 treatment group (systemic imipenem) and 3 control groups (noninfected burn, infected nonburned, and burn with distant infection). Seven-day mortality, quantitative culture from eschars and from spleens, weight loss, and time to healing were compared. RESULTS: The 25%-100% mortality rate in the nontreated PA-infected burn group was directly related to the infecting inoculum. Imipenem treatment reduced the mortality rate to 0-17%. No control animal died. Systemic bacterial dissemination at 48 hours was significantly higher in the study group. Morbidity paralleled survival results. Wound healing was quicker in the imipenem-treated group and control groups compared with the infected nontreated group. CONCLUSIONS: The mice model is a useful tool for evaluating new antibacterial agents and strategies for treating PA-infected burn injuries. Imipenem was found to be efficacious in the treatment of severe PA sepsis.

Antibodies raised against N'-terminal Pseudomonas aeruginosa flagellin prevent mortality in lethal murine models of infection.

The goal of this study was to investigate if antibodies raised against N'-terminal Pseudomonas aeruginosa (Pa) flagellin could afford protection in two lethal mouse models of Pa infection. To that end, rabbit polyclonal antibodies were generated against the N'-terminal domains (amino acids 1-156) of recombinant Pa01 or Salmonella muenchen flagellins, termed anti-N'-fla-b and anti-N'-fla-Sm, respectively. In vitro, anti-N'-fla-b but not anti-N'-fla-Sm IgG specifically recognized recombinant and Pa endogenous flagellin type b proteins, total bacterial lysates of Pa type b, and inhibited Pa01 invasion into A549 cells. In vivo, administration of anti-N'-fla-b afforded a remarkable improvement in survival in lethal peritonitis (90% vs. 12% in control; p<0.001) and burn infection (83% vs. 8-17% in control groups; p<0.005) Pa models. These findings would suggest that the N'-terminal domain of Pa flagellin harbors critically important bioactive domains and that an antibody-targeted, neutralization approach directed at this region could provide a novel therapeutic strategy to combat Pa infection.

Occurrence and phenotypic characteristics of extended-spectrum beta-lactamases among members of the family Enterobacteriaceae at the Tel-Aviv Medical Center (Israel) and evaluation of diagnostic tests.

We assessed the prevalence and phenotypic characteristics of extended-spectrum beta-lactamase (ESBL) producers among cefuroxime-resistant (CXM-R) (MIC > or = 32 micro g/ml) members of the family Enterobacteriaceae in our institution. The 438 CXM-R clinical isolates obtained from nonurine sources among inpatients were screened. ESBL production was confirmed by disk diffusion assay using cefpodoxime (CPD), cefotaxime (CTX), and ceftazidime (CTZ) with and without clavulanate (CLAV). A difference of > or =5 mm in the size of the zone of inhibition in the presence of CLAV for at least one of the agents was considered representative of the ESBL phenotype: 186 isolates (42.5%) were confirmed as ESBL producers. The isolates tested and the rates of ESBL producers were as follows: Klebsiella spp. (n = 81), 79%; Proteus spp. (n = 58), 62%; Escherichia coli (n = 64), 53%; Enterobacter spp. (n = 69), 42%; Serratia spp. (n = 70), 14%; Citrobacter spp. (n = 25), 24%; Providencia spp. (n = 21), 24%; Morganella spp. (n = 41), 5%; and Kluyvera (n = 3), 0%. The overall sensitivity of isolated ESBL confirmatory tests was 79% for CPD-CLAV, 66% for CTZ-CLAV, and 91% for CTX-CLAV. Sensitivities of CTZ-CLAV confirmatory tests for Klebsiella spp., Proteus spp., E. coli, and Enterobacter spp. were 84, 22, 76, and 62%, respectively, and those for CTX-CLAV were 95, 97, 94, and 83%, respectively. They were 90% for CPD-CLAV and CTZ-CLAV, 95% for CPD-CLAV and CTX-CLAV, and 100% for CTZ-CLAV and CTX-CLAV. ESBL production was highly prevalent among Enterobacteriaceae. Using resistance to CXM as an ESBL screening criterion is a suitable option in high-incidence areas where Klebsiella spp. are not the dominant ESBL producers. This screening criterion may simplify the screening test and improve its sensitivity, although at the price of testing more isolates. The CTX-CLAV combination confirmed ESBL producers better than the CTZ-CLAV combination, with sensitivity varying between species. Combined CTZ-CLAV and CTX-CLAV testing detected all these strains; CPD-CLAV provided no additional benefit.