Is there an association between periprosthetic joint infection and low vitamin D levels?

Purpose

Vitamin D is increasingly being recognized as an important mediator of immune function and may have a preventive role in the pathogenesis of periprosthetic joint infection. To the best of our knowledge, no other study has examined possible associations between periprosthetic joint infection and vitamin D deficiency. We investigated the rate of vitamin D deficiency in patients treated for periprosthetic joint infection and whether vitamin D deficiency is independent of other risk factors for vitamin D deficiency in patients with periprosthetic joint infection.

Methods

Serum 25-hydroxyvitamin D (25OHD) levels of every patient scheduled to receive a total prosthesis either of the hip, knee, or shoulder in the orthopaedic department of the Johannes-Guttenberg-University Hospital in Mainz, Germany (109 patients), were measured after admission. Furthermore, serum 25OHD levels were measured for every patient presenting with periprosthetic joint infection (n = 50) or aseptic loosening of the prosthesis (n = 31) scheduled to undergo revision surgery. The prevalence of normal (>30 ng/ml), insufficient (20–30 ng/ml), and deficient (<20 ng/ml) 25OHD levels was determined.

Results

All tested patient subgroups showed low vitamin D levels. Statistical analysis found no significant difference in vitamin D levels comparing patients with prosthesis and patients with aseptic prosthesis loosening (p = 0.58). Significant differences in 25OHD levels were found comparing patients with periprosthetic joint infection and patients scheduled for primary arthroplasty (p < 0.001). In addition, we found a significant difference (p < 0,001) in 25OHD levels of patients with periprosthetic joint infection compared with patients with aseptic prosthesis loosening.

Conclusion

We found a high frequency of vitamin D deficiency in patients being treated by primary arthroplasty and those with aseptic joint prosthetic loosening and periprosthetic joint infection. Vitamin D deficiency was severe in patients with periprosthetic joint infection.     

A randomized controlled trial of the effect of spironolactone on left ventricular mass in hemodialysis patients

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Pneumocyte Apoptosis Induction during Cardiopulmonary Bypass: Effective Prevention by Radical Scavenging Using N-Acetylcysteine

Cardiopulmonary bypass (CPB) and cardioplegic arrest are associated with pulmonary dysfunction. We sought to investigate whether pulmonary ischemia/reperfusion during standard CPB and cardioplegic arrest is associated with reactive oxygen species (ROS)-mediated pulmonary tissue injury and pneumocyte apoptosis induction, and whether ROS scavenging using N-acetylcysteine (NAC) attenuates these alterations. Twelve pigs (41 ± 8 kg) were randomized to receive either NAC (100 mg/kg prior to CPB; n = 7) or placebo (n = 5) and subjected to CPB and 60 min of cold (4°C) crystalloid cardioplegic arrest. We collected lung biopsies prior to CPB, at 60 min CPB, as well as at 30, 60, and 120 min post CPB. Lung specimens were immunocytochemically stained against nitrotyrosine, 8-isoprostaglandin-F₂α, and 8-hydroxy-2′-deoxyguanosine (8-OH-dG) as indicators for ROS-mediated tissue injury and active caspase-3, an apoptosis signal pathway key enzyme. Oxidative stress markers were judged using a scale from 1 to 4 (low to intensive staining), and caspase-3-positive pneumocytes were counted per view field. In placebo, the number of caspase-3-positive pneumocytes significantly increased over time to reach a maximum at 120 min post CPB (p =. 03 vs baseline). NAC significantly prevented caspase-3 activation in pneumocytes (p =. 001 vs Placebo). Pneumocyte nitrotyrosine and 8-OH-dG staining significantly increased over time (p =. 003) in the placebo group, but decreased in the NAC group (p =. 004). In both groups staining for 8-isoprostaglandin-F₂α showed no significant changes. This yields the conclusion that standard CPB and cardioplegic arrest initiate ROS-mediated tissue injury and apoptosis in pneumocytes that can be reduced by NAC. Thus, ROS scavenging using NAC may represent a novel approach to minimize lung injury associated with CPB.     

Lessons and challenges during a 5-year follow-up of 21 Composix Kugel implantations

Introduction

From its introduction in 2000 until its US recall in December 2005, the Composix Kugel mesh was implanted in an estimated 350,000 patients worldwide. In our patients, minor postoperative complications were followed after a few years by more serious problems (persistent abdominal pain, infections, intestinal perforations). In this study, we take stock after a 5-year follow-up and issue a plea for improved product development strategies and the creation of hernia registries.

Patients and methods

Between 2003 and 2006, we implanted the Bard^® Composix^® Kugel^® mesh in 21 patients (11 men, 10 women, mean age 63.2 ± 13.7 years) with incisional hernias using the open intraperitoneal onlay mesh technique. The mesh is made on one side of ePTFE and on the other of polypropylene and is expanded by a polyethylene (PET) memory recoil ring. The average follow-up was 45.5 months. All patients had at least one risk factor for hernia recurrence. Explanted prostheses were analyzed by scanning electron microscopy (SEM) and subjected to mechanical strength tests.

Results

During the postoperative course, six patients suffered a wound healing disorder. Ten patients complained of persistent abdominal wall pain and four experienced recurrence of the hernia. In one patient, the mesh had to be explanted due to chronic infection. In one patient, the PET memory recoil ring broke after 5 years of follow-up with consequent small bowel perforation. The PET memory recoil ring exhibited clear signs of degradation on SEM and unmistakable signs of material fatigue in a materials testing machine.

Conclusions

Patients with recalled Composix Kugel meshes face a singular risk for complications that may occur even many years after implantation. The most serious complication is the breakage of its PET memory recoil ring. Since the recall of the Composix Kugel Mesh, we have discontinued its use. It is necessary that future complications are documented in a common post-market surveillance registry. Algorithms need to be developed and promoted to support affected patients and surgeons.     

Comparison of three-dimensional rotational angiography with digital subtraction angiography in the assessment of ruptured cerebral aneurysms

BACKGROUND AND PURPOSE: Rotational angiography (RA) and digital subtraction angiography (DSA) together may depict more intracranial aneurysms than DSA alone. We compared the diagnostic value of 3D RA and biplanar DSA in detecting, classifying, and planning treatment for ruptured intracranial aneurysms. METHODS: A total of 53 patients with acute subarachnoid hemorrhage (Hunt and Hess grades I-V) underwent angiography with both methods. DSA was performed in two to six standard projections in every vascular territory. Three-dimensional RA datasets were evaluated by using surface-shaded display and maximum intensity projection. The usefulness of DSA images and 3D datasets in detecting aneurysms (number, configuration) and treatment planning were retrospectively analyzed in a blinded manner. RESULTS: In 42 patients, 56 aneurysms were detected, (one to five per patient; size, 0.6-20.4 mm); no aneurysm was found in 11 patients. RA revealed seven aneurysms not seen at conventional DSA. RA failed to depict one aneurysm visible only in a compression series. Delineation of the aneurysmal neck improved with RA in 71% of cases; the parent vessel and its relationship to adjacent vessels was demonstrated better with RA than with DSA in 45% and 50%, respectively. Endovascular treatment was proposed in nine patients; microsurgical therapy, in 26. In seven patients, both options were rated as being equal. Actual treatment consisted of eight endovascular procedures and 30 neurosurgical operations. Four patients died before therapy. CONCLUSION: Compared with DSA, 3D RA allows more exact depiction of anatomic details that are important in planning surgery and interventional therapy for intracranial aneurysms. RA depicted more aneurysms.     

Physikalische Grundlagen und klinische Durchführung der interstitiellen Brachytherapie der Prostata mit Jod-125

BACKGROUND: Interstitial brachytherapy with I-125 seeds can be used for successful treatment of early stage prostate cancer. There is presented the technique of permanent transperineal implantation of I-125 seeds with intraoperative treatment planning which is suited for the treatment of prostate cancer up to the clinical stage of T2a. MATERIAL AND METHODS: Some weeks before the implantation of the seeds the prostate volume is determined using transrectal ultrasound (TRUS) so as to estimate the required number of I-125 seeds. At the outset of the treatment the prostate is stabilized by two perineally inserted needles. Subsequently there is carried out an ultrasound guided treatment planning that allows to optimize the distribution of the seeds within the prostate. In interstitial brachytherapy we use RAPID STRANDS((R)), i. e. the I-125 seeds are embedded in vicryl suture at distances of 1 cm. During implantation of the I-125 seeds the transversal placement of the applicator needles is controlled by TRUS and the cranio-caudal placement of the applicator needles is controlled using the fluoroscopic unit as well as TRUS. About 4 weeks after the implantation of the seeds there is carried out a postoperative computation of the dose distribution of the implant using CT imaging. RESULTS: The procedure possesses the advantage that ultrasound imaging, treatment planning and seed implantation are carried out with the prostate remaining in an unaltered position. During implantation the combined imaging of TRUS and fluoroscopy allows a safe placement of the seeds with in the prostate. CONCLUSION: The methods for the calculation of the actually attained dose distribution must still be optimized, because the postoperative examination of the individual results has so far been possible only with difficulties resulting from methodological inconveniences.     

Grading of vestibular schwannomas and corresponding tumor volumes: ramifications for radiosurgery

Background

Patients with vestibular schwannomas (VS) are either assigned to watchful waiting, microsurgical resection, or radiosurgery. Decision making on how to proceed is based on parameters such as age, tumor growth, loss of hearing, and the tumor’s Koos grading.

Methods

In order to correlate Koos grading with tumor volume, patient records of 235 patients with VS who underwent Gamma Knife radiosurgery (GKRS) were retrospectively reviewed.

Results

From 1994 to 2009, 235 consecutive patients underwent GKRS for sporadic VS at the Zurich Gamma Knife Center. Median follow up was 62.8 ± 33.0 months. Of the 235 tumors, 32 (13.6 %) were graded Koos I with a volume of 0.25 ± 0.3 cc; 71 (30.2 %) were graded Koos II with a volume of 0.57 ± 0.54 cc; 70 (29.8 %) were graded Koos III with a volume of 1.82 ± 1.88 cc; and 62 (26.4 %) were graded Koos IV with a volume of 4.17 ± 2.75 cc. Tumor progression was defined as a volume increase > 20 % at 2 years or later following GKRS. Overall tumor progression occurred in 21/235 (8.9 %) patients at 3.4 ± 0.9 years. Tumor progression did not differ statistically significantly in the various Koos grades: 1/32 (3.1 %) patients with VS Koos Grade I, 7/71 (9.8 %) patients with VS Koos Grade II, 6/70 (8.6 %) patients with VS Koos Grade III, and 7/62 (11.3 %) patients with VS Koos Grade IV.

Conclusion

To our knowledge, this is the first work correlating the various Koos grades of VS to their respective tumor volumes. In our patients, tumor volumes of VS Koos Grade IV were limited because all of our patients were eligible for radiosurgery. In our series, the outcome following GKRS for patients with VS Koos Grade IV tumors did not differ from patients with VS Koos Grades I–III. We therefore suggest to limit Koos Grade IV VS to tumor volumes < 6 cc that may be eligible for radiosurgery, and introduce an additional VS Grade V for large VS with tumor volumes of > 6 cc that may not be eligible for radiosurgery.     

Pretreatment with β‐adrenergic receptor agonists facilitates induction of LTP and sharp wave ripple complexes in rodent hippocampus

Norepinephrine, is involved in the enhancement of learning and memory formation by regulating synaptic mechanisms through its ability to activate pre‐ and post‐synaptic adrenergic receptors. Here we show that β‐agonists of norepinephrine facilitate the induction of both associational LTP and sharp wave ripples (SPW‐Rs) in acute slices of rat hippocampus in area CA3. Surprisingly, this facilitating effect persists when slices are only pretreated with β‐receptor agonists followed by wash out and application of the unspecific β‐adrenoreceptor (βAR) antagonist propranolol. During application of βAR agonists repeated stimulation resulted in facilitated induction of SPW‐Rs. Since SPW‐Rs are thought to be involved in memory replay we studied the effects of βAR‐agonists on spontaneous SPW‐Rs in murine hippocampus and found that amplitude and incidence of SPW‐Rs increased. These effects involve cyclic‐AMP and the activation of protein kinase A and suggest a supportive role in memory consolidation. © 2016 Wiley Periodicals, Inc.