Israel Medical Association Journal

Mesenchymal stem cells, or mesenchymal stromal cells, have emerged as a major new cell technology with a diverse spectrum of potential clinical applications. MSCs[1] were originally conceived as stem/progenitor cells to rebuild diseased or damaged tissues. Over the last 14 years, since the first report of MSC infusions in patients, the cells have been shown to suppress graft vs. host disease, stimulate linear growth in a genetic disorder of bone, and foster engraftment of haplo-identical hematopoietic stem cells. In all cases, few, if any, MSCs were identified at the site of clinical activity. This experience suggests a remarkable clinical potential, but a different general mechanism of action. Systemically infused MSCs seem to exert a therapeutic effect effect through the release of cytokines that act on local, or perhaps distant, target tissues. Rather than serving as stem cells to repair tissues, they serve as cellular factories that secrete mediators to stimulate the repair of tissues or other beneficial effects. Since both the tissue source of MSCs and the ex vivo expansion system may significantly impact the cytokine expression profile, these parameters may be critically important determinants of clinical activity. Furthermore, cell processing protocols may be developed to optimize the cell product for a specific clinical indication. For example, MSC-like cells isolated from placenta and expanded in a three-dimensional bioreactor have recently been shown to increase blood flow in critical limb ischemia. Future efforts to understand the cytokine expression profile will undoubtedly expand the range of MSC clinical applications.

The incidence of aortic valve stenosis is growing rapidly in the elderly. Nonetheless, many symptomatic patients are not referred for surgery usually because of high surgical risk. Unfortunately, percutaneous balloon valvuloplasty is unsatisfactory due to high recurrence rates. In 2002, Cribier and colleagues were the first to describe percutaneous aortic valve implantation, opening a new era of aortic stenosis management. In the present review we report a patient treated by this novel method, discuss and assess how it is implanated, report the findings of studies conducted to date, and suggest future directions for percutaneous treatment of aortic valve disease.
 

Background: Monitoring the rate of infections in individual centers that treat patients with hematological malignancies is of major importance. However, there are no uniform guidelines for infection surveillance.

Objectives: To describe the epidemiology of bacterial and fungal infections in a single hematology ward and to compare methods for reporting surveillance and infection rates in other centers in Israel.

Methods: We conducted a prospective surveillance of all patients admitted to our hematology ward, applying standard definitions for invasive fungal infections and adapting definitions for non-fungal infections. Incidence rates were calculated using patients, admissions, hospital days and neutropenia days. We performed a search for other reported surveillance studies in Israel.

Results: We detected 79 infectious episodes among 159 patients admitted to the hematology ward during 1 year. Using neutropenia days as the denominator for calculation of incidence discriminated best between patients at high and low risk for infection. The incidence of invasive fungal infections was 7, 10 and 18 per 1000 neutropenia days, among all patients, those with acute leukemia and those with acute leukemia undergoing induction therapy, respectively. Only 10 reports from Israel were identified, 6 of which were prospective. Our data could not be compared to these reports because of the varying definitions and denominators used.

Conclusions: Hematology centers should monitor infection rates and report them in a uniform methodology.
 

Background: Early-onset neonatal sepsis is a major cause of morbidity and mortality among newborn infants.

Objectives: To determine the incidence, type of pathogens and resistance to antibiotics among newborns with early-onset neonatal sepsis, and to identify the risk factors predisposing infants to resistant pathogens in order to reevaluate antibiotic regimens appropriate for resistant bacteria in these high risk neonates.

Methods: We retrospectively studied maternal and neonatal variables of 73 term and near-term infants and 30 preterm infants, born over a period of 10.5 years and exhibiting early-onset neonatal sepsis (positive blood cultures in the first 72 hours of life).

Results: Predominant pathogens in term and near-term infants were gram-positive compared with gram-negative organisms (mostly Escherichia coli) in preterm infants. Mothers of infants with antibiotic-resistant organisms were more likely to have prolonged rupture of membranes and prolonged hospitalization before delivery and to be treated with antibiotics. No trends towards more resistant strains of pathogens were recorded over the 10.5 years of the study period.

Conclusions: Early-onset neonatal sepsis in term infants differs in bacterial species from that in preterm infants, with predominantly gram-positive organisms in term and near-term infants and gram-negative organisms in preterms. Rates of bacterial resistance to the combination of ampicillin and gentamicin, though higher among infants born to mothers with prolonged hospitalization who had been treated with antibiotics, still remained very low in our department. Thus, it seems that our classic antibiotic regimen is still appropriate for both term and preterm newborns.
 

Background: Aural cholesteatoma is an epidermal cyst of the middle ear or mastoid that can only be eradicated by surgical resection. It is usually managed with radical or modified radical mastoidectomy. Clinical diagnosis of recurrent cholesteatoma in a closed postoperative cavity is difficult. Thus, the accepted protocol in most otologic centers for suspected recurrence consists of second-look procedures performed approximately 1 year after the initial surgery. Brain herniation into a post-mastoidectomy cavity is not rare and can be radiologically confused with cholesteatoma on the high resolution computed tomographic images of temporal bones that are carried out before second-look surgery.

Objectives: To present our experience with meningoceles that were confused with recurrent disease in patients who had undergone primary mastoidectomy for cholesteatoma and to support the use of magnetic resonance imaging as more suitable than CT in postoperative follow-up protocols for cholesteatoma.

Methods: We conducted a retrospective chart review of four patients.

Results: Axial CT sections demonstrated a soft tissue mass in the middle ear and mastoid in all four patients. Coronal reconstructions of CT scans showed a tympanic tegmen defect in two patients. CT failed to exclude cholesteatoma in any patient. Each underwent a second-look mastoidectomy and the only finding at surgery was meningocele in all four patients.

Conclusions: Echo-planar diffusion-weighted MRI can differentiate between brain tissue and cholesteatoma more accurately than CT. We recommend that otolaryngologists avoid unnecessary revision procedures by using the newest imaging modalities for more precise diagnosis of the patients who had undergone mastoidectomy for cholesteatoma in the past.
 

Background: The QT interval reflects the total duration of ventricular myocardial repolarization. Its prolongation is associated with increased risk of polymorphic ventricular tachycardia, or torsade de pointes, which can be fatal.

Objectives: To assess the prevalence of both prolonged and short QT interval in patients admitted to an acute geriatric ward.

Methods: This retrospective study included the records over 6 months of all patients hospitalized in an acute geriatric ward. Excluded were patients with pacemaker, bundle branch block and slow or rapid atrial fibrillation. The standard 12 lead electrocardiogram of each patient was used for the QT interval evaluation.

Results: We screened the files of 422 patients. QTc prolongation based on the mean of 12 ECG leads was detected in 115 patients (27%). Based on lead L2 only, QTc was prolonged in 136 (32%). Associated factors with QT prolongation were congestive heart failure and use of hypnotics. Short QT was found in 30 patients (7.1%) in lead L2 and in 19 (4.5%) by the mean 12 leads. Short QT was related to a higher heart rate, chronic atrial fibrillation and schizophrenia.

Conclusions: Our study detected QT segment disturbances in a considerable number of elderly patients admitted acutely to hospital. Further studies should confirm these results and clinicians should consider a close QT interval follow-up in predisposed patients.
 

Background: Although unprotected left main coronary artery disease is considered by contemporary guidelines to be an indication for surgery, percutaneous coronary intervention may be necessary in patients at high surgical risk.

Objectives: To assess the outcome of angioplasty in the treatment of unprotected LMCA[1] disease.

Methods: Angiographic and clinical data were collected prospectively for all patients who underwent emergent or non-emergent (planned) therapeutic PCI[2] for unprotected LMCA disease at our center from 2003 to 2007. Baseline values were compared with findings at 1, 6 and 12 months after the procedure.

Results: The study group comprised 71 consecutive patients with a mean age of 74 ± 12 years; 63% were men, and 31% had diabetes. Forty-three patients had a planned procedure and 28 an emergent procedure. Mean EuroScore was 7.3 ± 3.6 (range 5–12). Forty-nine percent of the procedures were performed with bare metal stents and 51% with drug-eluting stents. Procedural success was achieved in 100% of cases. The overall mortality rate was 11.3% at 1 month, 18.3% at 6 months and 19.7% at 12 months. Elective PCI was associated with significantly lower mortality (2.3% vs. 25% at 1 month, 4.6% vs. 39% at 6 months and 6.9% vs. 39% at 12 months), and the use of drug-eluting stents was associated with lower rates of target vessel revascularization and major adverse cardiac events than use of bare metal stents (2.8% vs. 14% at 1 month, 8.3% vs. 43% at 6 and 12 months). Variables that correlated with increased mortality or MACE[3] at 6 and 12 months were cardiogenic shock, emergent PCI, ejection fraction < 35%, renal failure, distal left main stenosis location, and reference diameter < 3 mm.

Conclusions: PCI is a feasible and relatively safe therapeutic option for unprotected LMCA. The less favorable outcome of emergent compared to planned PCI is probably attributable to the overwhelming acute myocardial ischemic injury in emergent cases. The use of drug-eluting stents may improve the intermediate-term restenosis rate.

[1] LMCA = left main coronary artery

[2] PCI = percutaneous coronary intervention

Background: Elastofibroma is a rare type of lesion consisting of elastic fibers within a stroma of collagen and fatty tissue. It is usually located on the lower scapular region attached firmly to the thoracic cage, often causing debilitating pain. Its clinical presentation mimics a soft tissue tumor.

Objectives: To evaluate the diagnosis and treatment results of elastofibroma.

Methods: Clinical and radiographic evaluations were performed in 11 patients with thoracic wall mass. In five of them a biopsy was taken before surgery. All patients were operated and the diagnosis of elastofibroma was confirmed by histology. 

Results: Two patients had a postoperative seroma that resolved spontaneously within a few days. All patients resumed their preoperative activities, including sports.

Conclusions: Considering the slow-growing nature of this tumor and its typical presentation, we believe that when this diagnosis is suspected, investigation does not necessitate staging (as in sarcomas). Also, marginal surgical excision is sufficient. Observation is an acceptable alternative to surgery.