Isolation and identification of specific bacteriophages against methicillin-resistant Staphylococcus aureus, extended-spectrum beta-lactamases-producing Escherichia coli, extended-spectrum beta-lactamases-producing Klebsiella pneumoniae, and multidrug-resistant Acinetobacter baumanniiin vitro

Drug resistance of methicillin-resistant Staphylococcus aureus, extended-spectrum beta-lactamases-producing Escherichia coli and Klebsiella pneumoniae and multidrug-resistant Acinetobacter baumannii are also cited as one of the most important causes of community and hospital acquired infections. Phage therapy can be used as a therapeutic method for the treatment of infections caused by these bacteria. The aim of this study was to isolate bacteriophages from municipal wastewater and assess their effects against drug resistant bacterial strains. The single agar layer technique was used to investigate the bacteriolytic effect of bacteriophages. Then, the double agar layer technique was used to observe phage plaques and the transmission electron microscopy was used to study the morphology of the bacteriophages. Transparent plaque formation in a double agar layer test of methicillin-resistant S. aureus and extended-spectrum beta-lactamases-producing E. coli and K. pneumoniae indicated the lysis of bacterial cells by isolated bacteriophages. No bacteriophage against A. baumannii was isolated from municipal wastewater. The morphology of these bacteriophages was also identified by electron microscopy. The results of this study showed that bacteriophages act specifically and due to the increasing level of antibiotic resistance, phage therapy as a new treatment can open a new horizon for the treatment of multidrug resistant bacteria.

[Clinical Study of Skull Base Osteomyelitis]

Typical osteomyelitis is reportedly caused by Pseudomonous aeruginosa in elderly diabetic patients after malignant external otitis. Recently, complications have arisen due to the emergence of atypical osteomyelitis. We have experiensed 5 cases of skull base osteomyelitis at our hospital. All patients were male with a mean age of 75.2 years. Four patients had diabetes. Regarding the clinical and radiographic findings, patients 1, 2, and 3 had typical osteomyelitis after malignant external otitis, whereas patients 4 and 5 had atypical osteomyelitis without temporal bone findings. Sample culturing revealed Pseudomonas aeruginosa in 4 cases and Aspergillus in one. Intravenous antibiotics were administered to all patients. Two patients responded positively and survived, while 3 died. Typical osteomyelitis is reportedly caused by P. aeruginosa in elderly diabetic patients after malignant external otitis. Recently, complications have arisen due to the emergence of atypical osteomyelitis. The prognosis of skull base osteomyelitis is still poor in Japan. Early diagnosis and long-term antibiotic administration is required to improve outcome.

Endoscopic Cerebrospinal Fluid Leak Closure in an Infected Field

Background

Sinonasal cerebrospinal fluid (CSF) leaks during an active infection present the unique challenge of preventing spread of infection without compromising the integrity of the closure. We describe the technique and clinical course of patients undergoing endoscopic CSF leak repair in an actively infected field.

Objective

To evaluate the safety and efficacy of endoscopic CSF leak repair in an actively infected field.

Methods

Retrospective chart review of patients with sinonasal CSF leaks that were endoscopically repaired during an acute infection.

Results

Nine patients were identified. Etiologies of CSF leak were iatrogenic after endoscopic sinus surgery (n = 5, 55.6%) or revision craniopharyngioma resection (n = 1, 11.1%), spontaneous (n = 1, 11.1%), anterior skull base meningocele with CSF leak (n = 1, 11.1%), and posttraumatic (n = 1, 11.1%). The locations of the leaks were ethmoid in five patients, frontoethmoid in three patients, and sphenoid in three patients. Seven patients had acute sinusitis (77.8%) and two patients had meningitis (22.2%) at the time of closure. Two patients (22.2%) had failure of previous CSF leak closure. All leaks were repaired in a multilayered fashion with multiple graft types, including septal or conchal cartilage, temporalis fascia, fascia lata, fat, Medpor, and tissue sealant. Three patients additionally had mucosal flaps or grafts. The patients were treated with an average of 11.1 days (range, 6-14 days) of antibiotics. The average hospital stay was 4.1 days (range, 2-7 days), and the mean follow-up time was 8.7 months (range, 2.9-19.3 months). No patients experienced recurrence of CSF leak or postoperative complication or infection.

Conclusion

Endoscopic closure of skull base defects was successfully performed in nine patients during acute infections without complications, recurrent infection, or need for revision CSF leak closure. Endoscopic CSF leak repair appears to be safe and effective in patients with active infection with sinusitis or meningitis.

Community-acquired methicillin-resistant Staphylococcus aureus: the new face of an old foe?

The burden of infections caused by community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is increasing among different patient populations globally. As CA-MRSA has become established in healthcare facilities, the range of infections caused by them has also increased. Molecular characterization of CA-MRSA isolates obtained from different centers has revealed significant diversity in their genetic backgrounds. Although many CA-MRSA strains are still susceptible to non-β-lactam antibiotics, multiresistance to non-β-lactam agents has emerged in some clones, posing substantial problems for empirical and directed therapy of infections caused by these strains. Some CA-MRSA clones have acquired the capacity to spread locally and internationally. CA-MRSA belonging to ST80-MRSA-IV and ST30-MRSA-IV appear to be the dominant clones in the countries of the Gulf Cooperation Council (GCC). The emergence of pandemic CA-MRSA clones not only limits therapeutic options but also presents significant challenges for infection control. Continued monitoring of global epidemiology and emerging drug resistance data is critical for the effective management of these infections.