Factors associated with readmission and mortality in adult patients with skin and soft tissue infections.

BACKGROUND: Skin and soft tissue infections (SSTIs) are a common cause of consultation, and complicated cases require hospitalization. We describe factors that are related to readmission and/or mortality of hospitalized patients diagnosed with SSTIs. METHODS: Retrospective review of hospital-admitted patients with a diagnosis of cellulitis, abscess, hidradenitis, fasciitis, and Fournier's gangrene. Cases from January 2002 to October 2015 were extracted from the diagnostic codification database of the Archives and Clinical Documentation Department. FINDINGS: We studied 1,482 episodes of hospitalized patients diagnosed with SSTIs. There were 187 (12.3%) readmissions, the most frequent diagnosis was cellulitis (72.7%), and the most commonly isolated microorganism was Staphylococcus aureus (25; 30.1%). Factors associated with readmissions were healthcare-related infections (P = 0.002), prior antibiotic therapy (P < 0.001), ischemic heart disease (P = 0.01), chronic liver disease (P = 0.001), and diabetes mellitus (DM) (P = 0.006). The number of patients who died as a result of an infection was 34 (2.2%) and, in these patients, the most common diagnosis was also cellulitis (79.4%), which in 52.9% (P = 0.001) was community acquired. DM (P = 0.01), heart failure (P = 0.001), and chronic liver disease (P = 0.003) were the most frequent comorbidities. This group presented more complications (P < 0.005) such as endocarditis (P < 0.005), amputation (P = 0.018), severe sepsis (P < 0.005), and septic shock (P < 0.001). CONCLUSIONS: Readmitted patients had healthcare-related S. aureus infection, had received prior antibiotic therapy, and presented comorbid conditions such as ischemic heart disease, peripheral vascular disease, chronic liver disease, or DM. Comorbidities such as advanced age, DM, heart failure, and chronic liver disease were associated with complications and higher infection-related mortality.

Folic acid-modified mesoporous silica nanoparticles with pH-responsiveness loaded with Amp for an enhanced effect against anti-drug-resistant bacteria by overcoming efflux pump systems.

Efflux pump system-mediated bacterial multidrug resistance is one of the main causes of antibiotic failure. Therefore, it is necessary to develop a novel nanocarrier that could effectively inhibit drug-resistant bacteria by increasing the intake and retention time of antibiotics. Herein, we constructed a pH-responsive nanocarrier (MSN@FA@CaP@FA) with double folic acid (FA) and calcium phosphate (CaP) covered on the surface of mesoporous silica (MSN) by electrostatic attraction and biomineralization, respectively. Afterward, loading the nanocomposites with ampicillin (Amp) effectively increased the uptake and reduced the efflux effect in Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) by the specific targeting of FA. Moreover, Amp-MSN@FA@CaP@FA could specifically transport Amp to the bacterial infection site. Similarly, antibacterial experiments revealed that the Amp-MSN@FA@CaP@FA could significantly enhance the activity of Amp for inhibiting drug-resistant bacteria, without producing drug resistance. Additionally, the Amp-MSN@FA@CaP@FA could reduce the content of protein and inhibit the protein activity in drug-resistant bacteria, so that it destroyed the bacterial membrane and led to the bacteria death. In vivo antibacterial experiments showed that the Amp-MSN@FA@CaP@FA could effectively reduce the mortality of drug-resistant E. coli infection and promote wound healing of drug-resistant S. aureus infection. In summary, Amp-MSN@FA@CaP@FA has a potential for application in sustained-release nanostructures and to inhibit drug-resistant bacteria.

Biologically Active Substances from Marine Hydrobionts with Antibacterial Activity in Composition of New Wound Dressings.

The data on the experimental study of the efficacy of the gel wound dressings based on chitosan and calcium alginate containing bioactive substances from marine hydrobionts with complex therapeutic action (sulfated polysaccharides from brown algae, hydrolyzed bivalves, peptides from nerve ganglia of cephalopods) are described. The model of thermal burns complicated by Staphylococcus aureus infection was used. Planimetric and bacteriological investigations revealed pronounced wound healing and antibacterial effects of the gel coating. The gel containing sulfated polysaccharides from brown algae showed the highest wound healing activity.

Mandatory infectious diseases consultation for MRSA bacteremia is associated with reduced mortality.

OBJECTIVES: Although infectious disease (ID) consultation has been associated with lower mortality in Staphylococcus aureus bloodstream infections, it is still not mandatory in many centers. This study aimed at assessing the impact of ID consultation on diagnostic and therapeutic management of methicillin-resistant S. aureus (MRSA) bacteremia. METHODS: Retrospective cohort study of all patients with MRSA bacteremia from 2001 to 2010. ID consultations were obtained on request between 2001 and 2006 and became mandatory since 2007. RESULTS: 156 episodes of MRSA bacteremia were included, mostly from central venous catheter (32%) and skin and soft tissue (19%) infections. ID consultation coverage was 58% between 2001 and 2006 and 91% between 2007 and 2010. ID consultation was associated with more echocardiography (59% vs. 26%, p < 0.01), vancomycin trough level measurements (99% vs. 77%, p < 0.01), follow-up blood cultures (71% vs. 50%, p = 0.05), deep-seated infections (43% vs. 16%, p < 0.01), more frequent infection source control (83% vs. 57%, p = 0.03), a longer duration of MRSA-active therapy (median and IQR: 17 days, 13-30, vs. 12, 3-14, p < 0.01) and a 20% reduction in 7-day, 30-day and in-hospital mortality. CONCLUSIONS: ID consultation was associated with a better management of patients with MRSA bacteremia and a reduced mortality.

[Molecular epidemiology of Panton-Valentine leukocidin (PVL) -positive Staphylococcus aureus associated with skin and soft tissue infection].

Panton-Valentine leukocidin (PVL) secreted by Staphylococcus aureus is known to cause severe skin, soft tissue and lung infections. To assess the prevalence and genetic characteristics of PVL-positive S. aureus in our hospital, we investigated 86 S. aureus isolates isolated from skin and soft tissue pus between September 2011 and May 2012 at Daisan Hospital, the Jikei University School of Medicine (Tokyo, Japan). All isolates were investigated for the mecA gene and PVL gene by PCR amplification. The MRSA isolates confirmed were genotyped using SCCmec typing. PVL-gene positive isolates confirmed by the PVL-RPLA (reverse passive latex agglutination) assay were characterized by agr typing and multilocus sequence typing (MLST). Overall 6 (3 MSSA isolates and 3 MRSA isolates) PVL-positive strains (7.0%) were detected. The PVL prevalence was 11.1% in MRSA and 5.1% in MSSA. PVL-positive strains were isolated from young adults (range: 8-47 years) outpatient. Patients infected with PVL-positive MRSA were significantly younger than those infected with PVL-negative MRSA(32 and 68 years, respectively; P = 0.009, t-test). The 6 PVL positive strains were assigned by the MLST to 6 STs that were prevalent among PVL-positive strains. The SCCmec type of the PVL-positive MRSA were classified into 2 types (type IV or V) that were generally characteristic of CA-MRSA. Our data are consistent with some previous reports showing that PVL gene is found in certain ST strains. The PVL-positive strain must be taken into account when S. aureus is isolated from young adult SSTI.

Toxic epidermal necrolysis: Part II. Prognosis, sequelae, diagnosis, differential diagnosis, prevention, and treatment.

Toxic epidermal necrolysis (TEN) is a life-threatening, typically drug-induced, mucocutaneous disease. TEN has a high mortality rate, making early diagnosis and treatment of paramount importance. New but experimental diagnostic tools that measure serum granulysin and high-mobility group protein B1 (HMGB1) offer the potential to differentiate early TEN from other, less serious drug reactions, but these tests have not been validated and are not readily available. The mainstay of treatment for TEN involves discontinuation of the offending drug, specialized care in an intensive care unit or burn center, and supportive therapy. Pharmacogenetic studies have clearly established a link between human leukocyte antigen allotype and TEN. Human leukocyte antigen testing should be performed on patients of East Asian descent before the initiation of carbamezapine and on all patients before the initiation of abacavir. The effectiveness of systemic steroids, intravenous immunoglobulins, plasmapheresis, cyclosporine, biologics, and other agents is uncertain.

[Skin infections with MRSA. Epidemiology and clinical features]. / Hautinfektionen durch MRSA. Epidemiologie und Klinik.

Staphylococcus aureus is the most prevalent pathogen in dermatology causing a broad array of pyogenic, community-acquired (CA) and health care-associated (HA), acute and chronic, superficial and deep skin infections which can progress to life-threatening systemic infections. The pathogen causes also toxin-mediated diseases with cutaneous symptoms. Methicillin-resistant S. aureus (MRSA) strains are not sensitive to the beta-lactam antibiotics available in Germany. Even though they cause the same skin infections as methicillin -sensitive strains, they are associated with greater morbidity and mortality because of their resistance to therapy. In addition to HA-MSRA in hospitalized patients with well-known and defined risk factors, there are new CA-MSRA strains which arise in the community or from, animal husbandry sources. These MSRA strains are also a problem in hospitals today. CA-MRSA strains often have special virulence factors, such as Panton Valentine leukocidin), and are often associated with specific often recurrent skin and soft tissue infections (furuncles, abscesses, necrotizing entities).

Staphylococcus simulans osteitis in a diabetic patient.

Staphylococcus simulans was identified as the aetiological agent of osteitis in a diabetic woman. Its identifying characteristics and antibiogram were confirmed. Diabetic foot frequently becomes infected and the spread of infection to bone is a major causal factor behind lower-limb amputation. Early diagnosis and appropriate treatment are essential in such cases.

Trends in the incidence of methicillin-resistant Staphylococcus aureus infection in children's hospitals in the United States.

BACKGROUND: The incidence of and outcomes associated with methicillin-resistant Staphylococcus aureus (MRSA) infection in hospitalized children have been incompletely characterized. METHODS: We performed a retrospective, observational study using the Pediatric Health Information System, a database of clinical and financial data from >40 freestanding US children's hospitals. Using discharge coding data, we characterized S. aureus infections in children <18 years of age who were hospitalized during the period from 1 January 2002 through 31 December 2007. RESULTS: During this 6-year study period, we identified 57,794 children with S. aureus infection, 29,309 (51%) of whom had MRSA infection. The median age of patients with S. aureus infection was 3.1 years (interquartile range, 0.8-11.2 years), and less than one-third of these patients had complex, chronic medical conditions. Over time, there was a significant increase in cases of MRSA infection (from 6.7 cases per 1000 admissions in 2002 to 21.1 cases per 1000 admissions in 2007; P = .02, by test for trend), whereas the incidence of methicillin-susceptible S. aureus infection remained stable (14.1 cases per 1000 patient-days in 2002 to 14.7 cases per 1000 patient-days in 2007; P = .85, by test for trend). Of the 38,123 patients whose type of infection was identified, 23,280 (61%) had skin and soft-tissue infections. The incidences of skin and soft-tissue infection, pneumonia, osteomyelitis, and bacteremia that were caused by S. aureus increased over time, and these increases were due exclusively to MRSA. The mortality rate for hospitalized children with MRSA infection was 1% (360 of 29,309 children). CONCLUSIONS: There has been a recent increase in the number of hospitalized children with MRSA infection. This increase is largely driven by, but is not limited to, an increase in skin and soft-tissue infections. The mortality rate for hospitalized children with MRSA infection is low.

In vivo activity of the pyrrolopyrazolyl-substituted oxazolidinone RWJ-416457.

RWJ-416457 is an investigational pyrrolopyrazolyl-substituted oxazolidinone with activity against antibiotic-susceptible and -resistant gram-positive pathogens. Efficacies of RWJ-416457, linezolid, and vancomycin against methicillin-susceptible Staphylococcus aureus (MSSA) and community-associated methicillin-resistant S. aureus (CA-MRSA) in murine skin and systemic infections were compared, as were efficacies against Streptococcus pneumoniae in a lower respiratory infection. In staphylococcal systemic infections, RWJ-416457 was equipotent with to twofold more potent than linezolid, with 50% effective dose values ranging from 1.5 to 5 mg/kg of body weight/day. RWJ-416457 was two- to fourfold less potent than vancomycin against MSSA but up to fourfold more potent than vancomycin against CA-MRSA. In MSSA and CA-MRSA skin infections, RWJ-416457 demonstrated an efficacy similar to that of linezolid, reducing CFU/g skin approximately 1.0 log(10) at all doses tested; vancomycin yielded greater reductions than the oxazolidinones, with decreases in CFU/g skin of 3 log(10) (MSSA) and 2 log(10) (CA-MRSA). In the pneumococcal model, RWJ-416457 was two- to fourfold more potent than linezolid. The free-drug area under the concentration-time curves at 24 h (fAUC(24)) were similar for RWJ-416457 and linezolid. The half-life of RWJ-416457 was up to threefold longer than that of linezolid for all routes of administration. The fAUC(24)/MIC ratio, the pharmacodynamic parameter considered predictive of oxazolidinone efficacy, was approximately twofold greater for RWJ-416457 than for linezolid. Since the fAUC values were similar for both compounds, the higher fAUC/MIC ratios of RWJ-416457 appear to result from its greater in vitro potency. These results demonstrate that RWJ-416457 is a promising new oxazolidinone with efficacy in S. aureus or S. pneumoniae mouse infection models.

Complicated skin and soft tissue infections caused by methicillin-resistant Staphylococcus aureus: epidemiology, risk factors, and presentation.

BACKGROUND: Complicated skin and soft tissue infections (cSSTIs) present a challenge to healthcare providers. Methicillin-resistant Staphylococcus aureus (MRSA) is an increasing cause of these infections, particularly in certain countries. Surgeons and other healthcare providers need to understand cSSTIs and manage them effectively. METHODS: Review of the literature related to the pathogens associated with cSSTIs. RESULTS: In the United States, MRSA is a major cause of cSSTIs, and toxin-producing community-acquired MRSA (CA-MRSA) strains are increasing in prevalence. These strains are distinct from hospital-acquired MRSA (HA-MRSA). Infection with novel CA-MRSA in previously healthy individuals has emerged as an important public health problem. The virulence of these pathogens and their increasing prevalence in cSSTIs indicate that patients may be at higher risk for complications. CONCLUSIONS: There is a growing prevalence of MRSA, particularly in cSSTIs observed in both the community and the hospital setting. Early appropriate recognition and treatment of cSSTIs may improve patient outcomes.

The evaluation of nosocomial infection during 1-year-period in the burn unit of a training hospital in Istanbul, Turkey.

An analysis of the burned patients, admitted to our eight bed burn unit and treated between 1 January and 31 December 2000, was performed. Prevalence, etiologic agents, length of hospitalization, cost of treatment and mortality rates caused by nosocomial infections (NIs) were studied. The study included 63 patients. Eighteen of these (Group-A) had 24 NI episodes. The most common NI observed was burn-wound infection (58.3%), followed by bacteraemia-sepsis (16.7%). NIs were not detected in the rest at all (Group B). The mean length of hospitalization was 38.5+/-19.7 days in Group A, and 20.3+/-7.6 days in Group B. The mean total burned surface area (TBSA) was 43+/-21 in Group A and 29+/-18 in Group B, while the most important independent risk factor for NI was TBSA in burned patients (OR, 1.08; CI(95), 0.93-1.24). NI prolonged the mean hospital stay to 18 days and increased the cost of treatment by 502 US dollars. The most common bacteria isolated was Pseudomonas aeruginosa (41.7%) and the second was methicillin resistant Staphylococcus aureus (MRSA-25.0%). All of the NI-free patients survived, while, five (28.5%) patients with NI died (P<0.01). These findings emphasized the need for careful disinfection and conscientious contact control procedures in areas that serve immunosupressed individuals, such as burned patients.

Adverse events associated with methicillin-resistant Staphylococcus aureus in a nursing home.

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) generates concern in nursing homes. Restrictive isolation precautions may be applied for indefinite periods. Adverse events driving these concerns include transmission and infection. METHODS: The 721-bed Wisconsin Veterans Home in King performs approximately 645 cultures annually. The site, severity, and number of MRSA infections were determined for 69 months. Pulsed-field gel electrophoresis was performed on all initial isolates, followed by a statistical cluster analysis looking for evidence of transmission. RESULTS: Sixty-seven MRSA infections were identified (1.6 per 100 residents per year); many were polymicrobial, and it was difficult to determine the proportionate role of MRSA in morbidity or mortality. There was an episode of rapidly fatal MRSA septicemia in which empiric antibiotic therapy was ineffective. Twenty-one genetic strains were encountered. Statistical analysis identified 13 clusters of genetically identical strains clustered in time and space (P<.05). CONCLUSIONS: Infections with MRSA were identified at relatively low rates; however, the etiology of many serious nursing home infections is not determined, especially pneumonia. Statistical analysis revealed clustering and evidence of transmission. Nursing home practitioners should consider MRSA when applying empiric treatment to serious infections. We recommend a program including (1) judicious use of antibiotics, including topical agents, to reduce selection of resistant organisms; (2) obtaining and tracking cultures of infectious secretions to diagnose MRSA infections and focus antibiotic therapy; (3) universal standard secretion precautions because any resident could be a carrier; and (4) a detailed assessment and care plan for the carrier that maximizes containment of secretions and independence in activities. However, basic hygiene cannot be maintained in communal areas by some residents without restriction of activities of daily living.

[The chemoluminescence of the primary focus of a suppurative infection and of isolated neutrophils exposed to dimephosphon]. / Khemiliuminestsentsiia pervichnogo ochaga gnoinoi infektsii i izolirovannykh neitrofilov pri vozdeistvii dimefosfona.

The influence of dimephosphone at concentrations of 0.001 M-0.75 M on the chemiluminescence of tissues at the focus of purulent infection in the ear of a guinea pig, on the survival rate of the experimental animals injected with the lethal dose of Staphylococcus aureus, as well as on the spontaneous and stimulated chemiluminescence of blood neutrophils in patients with wound infection, was studied. The study showed that different concentrations of dimephosphone oppositely influenced the intensity of the chemiluminescence of neutrophil suspensions and tissues at the focus of infection: low concentrations were found to produce stimulating action and high concentrations, suppressive action. At the highest concentration used in this study (0.75 M) dimephosphone prevented the death of the animals receiving lethal doses of S. aureus.