Necrotizing fasciitis of the extremities in high and low Charlson Comorbidity Index: A multi-center retrospective cohort study.

BACKGROUND: Necrotizing fasciitis (NF) is a life-threatening and acute progressive soft tissue infection and needs early surgical intervention, that is, debridement or amputation. Surgical strategy or prognosis is influenced by the speed of progression and patients' general condition, which can be calculated by the Charlson Comorbidity Index (CCI). The purpose of this study was to investigate the association between the CCI scores and prognosis of patients with NF of the upper/lower extremities. METHODS: In the retrospective cohort study, we analyzed patients with NF of the upper/lower extremities who were determined to undergo surgery by orthopedic surgeons at four tertiary hospitals between August 2003 and April 2016. We divided the patients into two groups, Group L (low CCI scores of 0-2) and Group H (high CCI scores of ≥3). The primary event of this study was defined as death or amputation. Mortality cases were included when amputation was informed with documented certification but patients died while waiting for surgery. We compared the patients' background, laboratory data on admission, the laboratory risk indicator for necrotizing fasciitis (LRINEC) score, and primary outcome between the two groups. RESULTS: Of the 56 patients, 28 patients were classified into Group L and the other 28 patients into Group H. The data in this study showed that patients in Group H had lower white blood cell counts and hemoglobin and higher creatinine than Group L, but there was no difference in LRINEC scores between the two groups. Streptococcus pyogenes was the most common infectious agent in Group L (54%) but not in Group H (11%). Poorer outcome was observed in Group H compared with Group L (4 mortality and 16 amputation vs. no mortality and 9 amputation, P = 0.007). CONCLUSIONS: Laboratory data and causative microorganisms were different between high CCI and low CCI patients with NF. High CCI scores were associated with limb amputation or death caused by NF of the upper/lower extremities; whereas, low CCI scores were more likely associated with S. pyogenes monoinfection.

Non-replicating adenovirus based Mayaro virus vaccine elicits protective immune responses and cross protects against other alphaviruses.

Mayaro virus (MAYV) is an alphavirus endemic to South and Central America associated with sporadic outbreaks in humans. MAYV infection causes severe joint and muscle pain that can persist for weeks to months. Currently, there are no approved vaccines or therapeutics to prevent MAYV infection or treat the debilitating musculoskeletal inflammatory disease. In the current study, a prophylactic MAYV vaccine expressing the complete viral structural polyprotein was developed based on a non-replicating human adenovirus V (AdV) platform. Vaccination with AdV-MAYV elicited potent neutralizing antibodies that protected WT mice against MAYV challenge by preventing viremia, reducing viral dissemination to tissues and mitigating viral disease. The vaccine also prevented viral-mediated demise in IFN⍺R1-/- mice. Passive transfer of immune serum from vaccinated animals similarly prevented infection and disease in WT mice as well as virus-induced demise of IFN⍺R1-/- mice, indicating that antiviral antibodies are protective. Immunization with AdV-MAYV also generated cross-neutralizing antibodies against two related arthritogenic alphaviruses-chikungunya and Una viruses. These cross-neutralizing antibodies were protective against lethal infection in IFN⍺R1-/- mice following challenge with these heterotypic alphaviruses. These results indicate AdV-MAYV elicits protective immune responses with substantial cross-reactivity and protective efficacy against other arthritogenic alphaviruses. Our findings also highlight the potential for development of a multi-virus targeting vaccine against alphaviruses with endemic and epidemic potential in the Americas.

Skipping Pedicle Screw Insertion Into Infected Vertebra is a Risk Factor for Revision Surgery for Pyogenic Spondylitis in the Lower Thoracic and Lumbar Spine.

BACKGROUND: Surgical intervention for pyogenic spondylitis is indicated when conservative treatment fails and biomechanical instability persists. Whether to insert pedicle screws into all vertebrae, including the most erosive vertebrae, or whether to skip 1 vertebra in pedicle screw insertion remains controversial. METHODS: A single-institution retrospective cohort study was conducted in consecutive patients with pyogenic spondylitis in the lower thoracic and lumbar spine (T9-S1) between January 2008 and December 2016. The patients were treated with interbody fusion plus posterior stabilization using pedicle screws and were divided into 2 groups as follows: (1) patients in whom 1 vertebra, usually the most erosive, was skipped in pedicle screw insertion (Group Skipping) and (2) pedicle screw insertion into all vertebrae (Group All). Patients' operation data were evaluated, and clinical outcomes were compared between the 2 groups. There were no significant differences between the 2 groups in terms of age, sex, past histories, blood loss, operation time, the presence of abscesses, or operative approach. RESULTS: The length of fixation was greater by 1 vertebral level in the Group Skipping than in the Group All, and the rate of revision surgery for pseudarthrosis was higher in the Group Skipping than in the Group All (P = .02). There was no statistically significant difference between the 2 groups in terms of the mean segmental lordotic angle or Barthel Index. CONCLUSIONS: Skipping pedicle screw insertion for pyogenic spondylitis in posterior fixation led to an increased number of fixed vertebrae and may be a risk factor for revision surgery for pseudarthrosis. LEVEL OF EVIDENCE: 4. CLINICAL RELEVANCE: The insertion of short pedicle screws at the infected vertebra can prevent early treatment failure and increase the biomechanical stability of construct.

Vaccine-Induced Skewing of T Cell Responses Protects Against Chikungunya Virus Disease.

Chikungunya virus (CHIKV) infections can cause severe and debilitating joint and muscular pain that can be long lasting. Current CHIKV vaccines under development rely on the generation of neutralizing antibodies for protection; however, the role of T cells in controlling CHIKV infection and disease is still unclear. Using an overlapping peptide library, we identified the CHIKV-specific T cell receptor epitopes recognized in C57BL/6 infected mice at 7 and 14 days post-infection. A fusion protein containing peptides 451, 416, a small region of nsP4, peptide 47, and an HA tag (CHKVf5) was expressed using adenovirus and cytomegalovirus-vectored vaccines. Mice vaccinated with CHKVf5 elicited robust T cell responses to higher levels than normally observed following CHIKV infection, but the vaccine vectors did not elicit neutralizing antibodies. CHKVf5-vaccinated mice had significantly reduced infectious viral load when challenged by intramuscular CHIKV injection. Depletion of both CD4+ and CD8+ T cells in vaccinated mice rendered them fully susceptible to intramuscular CHIKV challenge. Depletion of CD8+ T cells alone reduced vaccine efficacy, albeit to a lesser extent, but depletion of only CD4+ T cells did not reverse the protective phenotype. These data demonstrated a protective role for CD8+ T cells in CHIKV infection. However, CHKVf5-vaccinated mice that were challenged by footpad inoculation demonstrated equal viral loads and increased footpad swelling at 3 dpi, which we attributed to the presence of CD4 T cell receptor epitopes present in the vaccine. Indeed, vaccination of mice with vectors expressing only CHIKV-specific CD8+ T cell epitopes followed by CHIKV challenge in the footpad prevented footpad swelling and reduced proinflammatory cytokine and chemokines associated with disease, indicating that CHIKV-specific CD8+ T cells prevent CHIKV disease. These results also indicate that a T cell-biased prophylactic vaccination approach is effective against CHIKV challenge and reduces CHIKV-induced disease in mice.

Adaptation and limitation of anterior column reconstruction for pyogenic spondylitis in lower thoracic and lumbar spine.

BACKGROUND: Surgical strategy for pyogenic spondylitis is controversial when vertebral body erosion is severe. Radical debridement and anterior column reconstruction is indicated for the purpose of early ambulatory to prevent secondary complication for long bed rest. However, such aggressive debridement and risk of perioperative complications are trade-off. The purpose of this study was to evaluate the risk factor of poor prognosis after anterior column debridement and reconstruction for pyogenic spondylitis in lower thoracic and lumbar spine. METHODS: We performed a retrospective review of 40 patients diagnosed with pyogenic spondylitis in lower thoracic and lumbar spine who were introduced to our institution due to losing ambulatory ability and underwent anterior column debridement and reconstruction between January 2008 and May 2016. After the patient population was split into a regaining ambulatory group (Group A; n = 23) and a poor prognosis group (Group P; n = 17), we used Fisher exact tests and t-tests as appropriate for univariate analyses to compare patient characteristics and outcomes between the 2 groups. RESULTS: Univariate analysis showed that the significant variables were massive bleeding (>2000 ml) (P < 0.01), Charlson Comorbidity Index ≥3 (P = 0.01), and two-stage surgery needed (P = 0.04). Logistic regression analysis showed that the factors associated with poor prognosis were massive bleeding (Odds Ratio 11.9; 95% confidence interval 1.8 to 119.7; P = 0.04). CONCLUSIONS: Massive bleeding was associated with poor prognosis after debridement followed by anterior column reconstruction for pyogenic spondylitis in lower thoracic and lumbar spine.

Successful management of prolonged venovenous extracorporeal membrane oxygenation in an octogenarian.

Venovenous extracorporeal membrane oxygenation is now an established treatment for acute respiratory distress syndrome. However, this treatment remains rare in octogenarians and is associated with poor outcomes. An 81-year-old man with a history of chronic obstructive pulmonary disease and heavy smoking underwent mitral and tricuspid valve repair and the Maze procedure for mitral and tricuspid regurgitation and paroxysmal atrial fibrillation. Although he was extubated the following day, his postoperative course was complicated with pneumonia followed by acute respiratory distress syndrome. He was reintubated on day 7. Ratio of partial pressure of arterial oxygen to fraction of inspired oxygen continuously dropped to less than 100 mmHg, and venovenous extracorporeal membrane oxygenation support was induced on day 18. His lung condition showed slow and steady recovery, and he was successfully weaned from mechanical support on day 44 (total support, 27 days). Bleeding complication from tracheotomy (day 31) due to disseminated intravascular coagulation was successfully managed using recombinant human soluble thrombomodulin. He was ambulatory and discharged to a nursing facility without tracheotomy on day 172. Proper extracorporeal membrane oxygenation management, while challenging to keep the elderly patient away from further complications, saved an 81-year-old patient.

Successful Repair of Regurgitant Pentacuspid Pulmonary Valve Combined With Pulmonary Artery Aneurysm.

Pentacuspid pulmonary valve is an extremely rare congenital anomaly. A 71-year-old woman presented with dyspnea on exertion. The preoperative examination showed a large pulmonary artery aneurysm with severe pulmonary regurgitation. The pentacuspid pulmonary valve was an intraoperative finding with four equivalent leaflets and one hypoplastic leaflet. The valve was successfully repaired by use of a bicuspidization technique combined with annuloplasty, and pulmonary artery reduction was performed. Postoperatively, the patient remained asymptomatic with trivial pulmonary regurgitation 1 year later. To our knowledge, this is the first report of a pentacuspid pulmonary valve repair.

Predictive factors of myasthenic crisis after extended thymectomy for patients with myasthenia gravis.

OBJECTIVES: Postoperative myasthenic crisis (POMC) is one of the serious complications after extended thymectomy for patients with myasthenia gravis (MG). This study aims to clarify the risk factors of POMC occurrence. METHODS: The clinical data of 55 MG patients (25 male, 30 female; median age, 51 years) who underwent extended thymectomy at Kyoto University from 2000 to 2013 were retrospectively reviewed. Surgical outcomes and pre- and perioperative predictive factors of POMC were analysed. RESULTS: The preoperative Myasthenia Gravis Foundation of America stage was I, II, III and IV in 24, 22, 8 and 1 patients, respectively. Ten patients (18.2%) developed POMC; 6 required prolonged intubation over 24 h and 4 required reventilatory support. All patients were weaned after 5.6 (2-26) days of ventilator support, and were discharged. Univariate analysis revealed a correlation with a high preoperative anti-acetylcholine receptor antibody titre (P = 0.009), history of myasthenic crisis (MC) (P = 0.0004) and unstable MG after preoperative medical therapy (P = 0.003). Multivariate logistic regression analysis showed history of MC (odds ratio, 11.84; 95% confidential interval, 1.05-372; P = 0.045) and unstable MG (odds ratio, 29.45; 95% confidential interval, 2.00-1063; P = 0.013) independently predicted POMC. The surgical response rate was not significantly different between the two groups (66.7% with POMC, 85.4% without POMC; P = 0.334). CONCLUSIONS: POMC occurred more frequently in unstable MG before surgery or in patients with a history of MC. Adequate preoperative medical therapy and perioperative care should be provided to these patients.

Effect of the thickness and nonlinear elasticity of tissue on the success of surgical stapling for laparoscopic liver resection.

Recently, the range of applications of surgical staplers has been extended to include laparoscopic liver resection because manipulation of a surgical stapler is very simple. Revealing the causes of stapling failure and suggesting a method to solve stapling failure are important for safe laparoscopic liver resection. Surgeons say that tissues make stapling more likely to fail if they are thick and brittle. However, the combinatorial effect of the thickness and stiffness of tissues on the success of surgical stapling for laparoscopic liver resection has not been investigated. Therefore, the objective of the present study was to investigate the effect of tissue thickness and tissue stiffness on the success rate (SR) of surgical stapling. From ex vivo stapling experimental results using pig livers, it is suggested that the effect of tissue thickness is greater than the effect of tissue stiffness on the SR of stapling. If tissue thickness is 5 mm, the SR of stapling is high regardless of the magnitude of the tissue-stiffness parameter. However, if tissue thickness is >10 mm, the SR of stapling has a relationship with nonlinear viscoelastic parameters. Therefore, the SR of stapling could be predicted from tissue thickness and nonlinear elastic parameters.

Portal vein thrombosis associated with ischemic colitis.

We report the case of a 52-year-old male who was admitted for sudden abdominal pain and hematochezia. Colonoscopy showed erosion and edema in the mucosa of the descending colon, leading to a diagnosis of ischemic colitis. Blood tests revealed hepatic dysfunctions. Using abdominal ultrasonography (US), thrombus was observed in the left branch of the portal vein and a part of the right branch. Although the Doppler method detected blood flow in the right branch, no blood flow signal was observed in the left branch. Since coagulation examinations were almost normal, and there was no past history of liver cirrhosis or malignancy, it was diagnosed to be portal vein thrombosis (PVT) associated with ischemic colitis. Anticoagulation therapy was initiated for PVT. According to the results of the US and abdominal computed tomography performed 3 months after starting the treatment, thrombus in the right branch had diminished but remained in the umbilical region of the left branch. Due to atrophy of the lateral segment of the liver, we terminated the treatment. Ischemic colitis is not a rare disease; however, when accompanying hepatic dysfunction, it is necessary to take the complications associated with PVT into consideration.

Repeatability analysis of rollover recognition in changing myoelectric electrode condition.

Bone cancer metastasis patients feel severe pain while performing rollover movement. We have been developing a robotic trunk orthosis to support the rollover movement in bed for bone cancer metastasis patients. In this support system, the myoelectric signal is used to recognize the start timing of the rollover movement. However, the characteristics of the myoelectric signal can change easily from long-term use and due to electrode misalignment. In this paper, the effects of long-term use and electrode misalignment in rollover movement were analyzed. It was found that continuous usage of less than 18 hours was suitable. In addition, the electrode was needed to be attached around the ASIS from 0 to 23 (deg) to obtain a large potential and quick response signal.

Development of a Micro-Macro Neural Network to recognize rollover movement.

Bone metastasis patients suffer from pain when their trunks twist during movements such as rollovers. In this overall research project, our ultimate aim is to develop an effective rollover-support system for patients with cancer bone metastasis. The core of this system will be a pneumatic rubber muscle that will be operated based on the EMG signals from the patient's internal abdominal oblique muscle to limit the range of motion of the trunk twist only when the patients will feel the pain. The Time Delay Neural Network (TDNN) is the traditional method for recognizing the movement such as rollover using EMG signals. We have developed a new neural network, called the Micro-Macro Neural Network (MMNN), to recognize the rollover movement earlier and with more accuracy than possible with the TDNN. Recognition using MMNN was 49 (S.D. 45) (msec) faster than that using TDNN. The recognition rate before the rollover started was improved from 38% (TDNN) to 86% (MMNN). Additionally, the number of false recognitions using MMNN fell to only one third of those using TDNN. In addition, by using the unit contribution rate of the neural network, we found that the MMNN effectively accounted for the importance of past EMG data (the data gathered before the current measurement point). We also found that the de-noising performance of the MMNN was effective.

[Overdose of vecuronium during general anesthesia to an infant].

We experienced an accidental case in which 5 mg of vecuronium was administered to a 5 kg infant boy, aged 2 months, incrementally for 55 minutes during general anesthesia. He received general anesthesia at the hospital where there is no anesthesiologist. After surgery the surgeon felt an unusual situation during emergence period from general anesthesia and then noticed overdose of vecuronium. They got in touch with our department immediately and requested us to follow him up. When we reached at the bedside, we could not observe voluntary movement by him. By using neuromuscular monitoring, we could determine that a paralysis was still maintained. After a while, he started to move and breathe himself. Extubation was performed safely 4 and half hours after the final administration of vecuronium. Finally, he could recover with no adverse effect. To predict the optimal dose of a non-depolarizing muscle relaxant to a pediatric patient, routine monitoring of neuromuscular block is effective and essential.

Peroral cholangioscopic treatment of hepatolithiasis: Long-term results.

BACKGROUND: Peroral cholangioscopic lithotomy is an effective treatment for extrahepatic bile duct stones. However, an evaluation of the usefulness and long-term results of peroral cholangioscopic lithotomy for hepatolithiasis has not been reported. The aim of this study was to evaluate the usefulness and long-term results of peroral cholangioscopic lithotomy for hepatolithiasis. METHODS: From August 1987 to July 1998, 36 consecutive patients underwent peroral cholangioscopic lithotomy for hepatolithiasis; 34 were followed for a mean of 93 months (range, 14 to 164 months). RESULTS: The rate of complete stone removal was 64%; the morbidity rate was 2.8%. The recurrence rate for patients in whom stones were completely removed was 21.7%. Two patients (5.9%) had cholangiocarcinoma develop during follow-up. CONCLUSION: Although incomplete stone removal and recurrence are common, peroral cholangioscopic lithotomy is a sufficiently safe and effective method for the treatment of hepatolithiasis.

Pulmonary Artery Calcification in Contact with a Left Coronary Artery Bypass Graft: An X-ray Computed Tomographic Study.

Calcification in the pulmonary artery (PA) occurs in rare cases. There have been no studies of calcification in the PA at the site of its contact with a left coronary artery bypass graft (CABG). In the present study, X-ray computed tomography (CT) was employed for examination of such calcification. The subjects were 53 patients (49 male and 4 female, mean age of 56.7 years) who underwent 74 left CABGs (69 saphenous veins and five internal thoracic arteries). Following surgery, non-contrasted CT was performed from the lower level of the aortic arch to the lower boundary of the left ventricle at 5-mm horizontal intervals, and contrasted CT was performed at the level of the PA; this procedure was repeated at approximately six-month intervals after the operation. In addition, aortography and selective graft angiography were carried out at 7.6 months postoperatively. The inner diameter of the grafts and the levels of serum cholesterol were also examined. Calcification in the PA was detected in 24 cases (all of them saphenous vein grafts), but graft angiography found no stenosis in those sites. Calcification size varied from 1 mm to 14 mm, with 10 of the cases at or exceeding 10 mm and showing high density. Only three of the cases enlarged with time. Calcification appeared at 2.9 to 54.3 months postoperatively and the mean time of onset was 10.0 +/- 15.7 months. The mean age of the patients with PA calcification was 58.7 +/- 5.9 years while that of the patients without calcification was 57.3 +/- 10.0 years. Graft diameter was 5.9 +/- 1.9 mm in the former group and 5.6 +/- 1.7 mm in the latter. Serum cholesterol level was 235 +/- 32 mg/dl in the former group and 243 +/- 42 mg/dl in the latter. There were three cases of occlusion in the calcification group, and four in the other. There were no significant intergroup differences in these four parameters. The incidence of CT-detected calcification in the PA was found to be high at its point of contact with saphenous vein grafts.