Borderline oxacillin-resistant Staphylococcus aureus (BORSA) are mecA-negative strains with oxacillin minimum inhibitor concentration (MIC) close to the resistance breakpoint of ≥ 4μg/mL. Instead of producing penicillin-binding protein with low affinity to methicillin (oxacillin) mediated by mecA gene as in methicillin-resistant S. aureus (MRSA), BORSA strains are characterised by the hyperproduction of β-lactamase enzymes, thus able to break down methicillin. Common laboratory methods to detect MRSA such as cefoxitin disk diffusion alone may fail to detect methicillin resistance due to BORSA. We report five cases of BORSA blood-stream infections in a university teaching hospital. All isolates were found to be susceptible to cefoxitin using disk diffusion, resistant to oxacillin using automated MIC method, and did not harbour mecA gene. All patients were suscessfully treated with anti-MRSA antibiotics, and removal of primary sources were done if identified. A more cost-effective method for screening and diagnosis of BORSA is needed in addition to cefoxitin disk diffusion test, in order to monitor the spread, and to enable routine detection and treatment of this pathogen.

Cosmetic surgeries are very popular and glamorized by the mainstream media and celebrities. Many individuals perceive certain bodily features as appealing for physical attraction and will attempt to obtain these features by surgery. However, these surgeries are not without risk, and significant consequences can occur if not performed by qualified medical professionals under sterile procedures. The authors present novel cases of two healthy young female patients who underwent a Brazilian butt lift (BBL) procedure a week apart by the same plastic surgeon in Mexico and developed dark painful lesions secondary to Mycobacterium abscessus (M. abscessus), a multidrug-resistant non-tuberculous mycobacterium (NTM). The literature review shows a paucity of data concerning NTM infections via surgical procedures of this type. The first case was of a 31-year-old woman who underwent a BBL and presented with bilateral dark painful buttock lesions weeks later. The patient returned to the plastic surgeon, who drained some lesions and prescribed oral antibiotics. The patient\'s clinical status continued to deteriorate and presented to the hospital for further assessment. The patient was initially started on broad-spectrum antibiotic therapy. The patient was found to have an HIV infection with a relatively preserved CD4 lymphocyte count and was started on antiretroviral therapy (ART). Intraoperative excisional tissue sample cultures grew M. abscessus. The patient was started on empiric tigecycline, cefoxitin, and linezolid. Preliminary culture susceptibilities showed resistance to linezolid. Linezolid was discontinued, amikacin was started, and cefoxitin and tigecycline were continued. Tigecycline, cefoxitin, and amikacin were continued and final susceptibilities showed sensitivity to the current treatment. The patient received a total of four months of treatment with tigecycline, cefoxitin, and amikacin. The second case was of a 28-year-old woman who underwent a BBL a week after the first patient by the same surgeon and developed multiple gluteal and body abscesses. The patient underwent bilateral thigh and gluteal, right chest wall, and breast surgical debridements with intraoperative cultures at a different hospital facility, which grew M. abscessus. Susceptibilities were not performed there. The patient was transferred to our facility for further care. Intraoperative cultures remained negative, and the patient was treated with a six-month course of tigecycline, cefoxitin, and amikacin.

Though prevalent in the environment, nontuberculous mycobacteria (NTM) have been increasingly identified as pathogenic. Sporadic reports of NTM infection of cardiac implantable electronic devices (CIEDs) have appeared but remain rare. This case describes a CIED infection with Mycobacterium abscessus, the third reported case in the literature. A 63-year-old male presented with a 3-day history of drainage from his pacemaker extraction site. An aspirate grew Mycobacterium abscessus Together with National Jewish Health, a treatment plan was developed, consisting of an induction phase with amikacin, cefoxitin and clarithromycin followed by a maintenance phase with clarithromycin and clofazimine. The clinical course was complicated by cardiac arrhythmia, abscess formation and thoracic osteomyelitis with epidural abscess. This case highlights a rare manifestation of Mycobacterium abscessus disease and suggests the need for further study. Treatment is complicated by unpredictable resistance patterns, complex antimicrobial regimens and the use of arrhythmogenic medications in patients with removed CIEDs.

The introduction of ustekinumab, an interleukin [IL]12/23 p40 inhibitor, to the therapeutic armamentarium of Crohn\'s disease has provided a much needed treatment option for patients who have failed conventional biologics with anti-tumour necrosis factor [TNF] and anti-integrin agents. Despite targeting two major cytokine pathways, the side effect profile of ustekinumab appears to be favourable in clinical trials. In particular, the risk of tuberculosis infection was observed to be lower than in patients who have received anti-TNF agents. The risk of non-tuberculosis mycobacterium infection, however, remains unknown. Here, we report the first case of a patient with Crohn\'s disease who developed Mycobacterium abscessus infection while on ustekinumab treatment.

Urban agricultural soils can be an important reservoir of antibiotic resistance, and have great food safety and public health indications. This study investigated antibiotic-resistant bacteria and antibiotic resistance genes in urban agricultural soils using phenotypic and metagenomic tools. In total, 207 soil bacteria were recovered from 41 soil samples collected from an urban agricultural garden in Detroit, MI, USA. The most prevalent antibiotic resistance phenotype demonstrated by Gram-negative bacteria was resistance to ampicillin (94.2%), followed by chloramphenicol (80.0%), cefoxitin (79.5%), gentamicin (78.4%) and ceftriaxone (71.1%). All Gram-positive bacteria were resistant to gentamicin, kanamycin and penicillin. Genes encoding resistance to quinolones, β-lactams and tetracyclines were the most prevalent and abundant in the soil. qepA and tetA, both encoding efflux pumps, predominated in the quinolone and tetracycline resistance genes tested, respectively. Positive correlation (P<0.05) was identified among groups of antibiotic resistance genes, and between antibiotic resistance genes and metal resistance genes. The data demonstrated a diverse population of antibiotic resistance in urban agricultural soils. Phenotypic determination together with soil metagenomics proved to be a valuable tool to study the nature and extent of antibiotic resistance in the environment.

OBJECTIVE: Methicillin-resistant Staphylococcus aureus (MRSA) strains carrying the mecC gene have been reported from humans and animals from several European countries, but never from Spain. We describe the first isolates of mecC-positive MRSA of human origin collected in Spain and report a fatal case of bacteraemia.
METHODS: Isolates were tested for phenotypic resistance using cefoxitin, tested for the mecA/mecC genes and toxin genes by PCR, and typed by staphylococcal cassette chromosome mec (SCCmec), PFGE, spa, multilocus sequence typing and agr.
RESULTS: During 2008-13 five MRSA isolates showing resistance to cefoxitin and carrying the mecC gene were recovered at one hospital in Spain. In a review of 5505 S. aureus strains received at the Spanish National Reference Centre for Staphylococci from the same period, we found two additional mecC-positive isolates. The isolates were recovered from blood (two), wounds (two), joint fluid (one), urine (one) and a nasal swab (one). All MRSA were mecA negative, presented SCCmecXI, belonged to agr group III and to clonal complex 130, and were negative for the production of the toxin genes tst1, eta, etb, etd and Panton-Valentine leucocidin. Six isolates belonged to spa type t843 (ST130 and ST1945, where ST stands for sequence type) and one to spa type t6220 (ST1945). One patient with mecC-positive MRSA sepsis died in the emergency department.
CONCLUSIONS: We confirm the presence of MRSA carrying the mecC gene in Spain, the ability of this livestock-associated MRSA to cause severe infections in humans and the need to perform culture-based susceptibility testing methods in order to detect these emerging strains.

Drug-induced immune hemolytic anemia is a rare but underdiagnosed and potentially fatal condition. We report a case of severe hemolytic anemia induced by cefoxitin in a 45-year-old woman admitted with menometrorrhagia. Hemoglobin levels reached a nadir of 4.7 g/dl approximately 72 h after cefoxitin initiation, and hemolysis resolved when cefoxitin was discontinued and prednisone 1 mg/kg was initiated. A transfusion reaction workup revealed no abnormalities. Direct antiglobulin testing was weakly positive with anti-C3. The patient\'s plasma and RBC eluate reacted with cefoxitin-treated RBCs but not with untreated RBCs in the presence or absence of cefoxitin.

We present a rare case of tracheobronchitis caused by Mycobacterium abscessus. The patient was a 79-year-old man with a previous history of tuberculosis. For smear examinations, he repeatedly expectorated many acid-fast bacilli. Bronchoscopic examination revealed the presence of ulceration on the lower end of the trachea and extending to the right main bronchus. Mycobacterial cultures were used to grow Mycobacterium abscessus. Following an antimicrobial regimen of clarithromycin, amikacin, and cefoxitin, the patient exhibited marked improvement. After initial multidrug therapy, the patient was placed on clarithromycin for 10 months. No relapse has occurred to date.

Salmonella infections lead to several clinical syndromes such as acute gastroenteritis and bacteremia. Less frequent manifestations are extraintestinal focal infections, including urinary tract infections. A 10-month-old boy was admitted to the hospital with recurrent urinary tract infections treated with antibiotics. Salmonella typhimurium was isolated from the urine samples obtained in urine bags. The organism was also grown from a suprapreputial swab, but was not grown in the suprapubic urine specimen. Renal ultrasonography, intravenous pyelography and voiding cystourethrogram were found normal. The patient was then circumcised, following with no uropathogens were isolated from the urine. It is believed that circumcision not only prevented further urinary tract infection and protected the case from becoming a carrier of Salmonella typhimurium, it also halted a possible spread of Salmonella infection to the general public.

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