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J S Solomkin

Publications and source records attributed to J S Solomkin.

At least 37 records · Page 2Linked to original sources

Results of a randomized trial comparing sequential intravenous/oral treatment with ciprofloxacin plus metronidazole to imipenem/cilastatin for intra-abdominal infections. The Intra-Abdominal Infection Study Group.

OBJECTIVE: In a randomized, double-blind, multicenter trial, ciprofloxacin/metronidazole was compared with imipenem/cilastatin for treatment of complicated intra-abdominal infections. A secondary objective was to demonstrate the ability to switch responding patients from intravenous (IV) to oral (PO) therapy. SUMMARY BACKGROUND DATA: Intra-abdominal infections result in substantial morbidity, mortality, and cost. Antimicrobial therapy often includes a 7- to 10-day intravenous course. The use of oral antimicrobials is a recent advance due to the availability of agents with good tissue pharmacokinetics and potent aerobic gram-negative activity. METHODS: Patients were randomized to either ciprofloxacin plus metronidazole intravenously (CIP/MTZ IV) or imipenem intravenously (IMI IV) throughout their treatment course, or ciprofloxacin plus metronidazole intravenously and treatment with oral ciprofloxacin plus metronidazole when oral feeding was resumed (CIP/MTZ IV/PO). RESULTS: Among 671 patients who constituted the intent-to-treat population, overall success rates were as follows: 82% for the group treated with CIP/MTZ IV; 84% for the CIP/MTZ IV/PO group; and 82% for the IMI IV group. For 330 valid patients, treatment success occurred in 84% of patients treated with CIP/MTZ IV, 86% of those treated with CIP/MTZ IV/PO, and 81% of the patients treated with IMI IV. Analysis of microbiology in the 30 patients undergoing intervention after treatment failure suggested that persistence of gram-negative organisms was more common in the IMI IV-treated patients who subsequently failed. Of 46 CIP/MTZ IV/PO patients (active oral arm), treatment success occurred in 96%, compared with 89% for those treated with CIP/MTZ IV and 89% for those receiving IMI IV. Patients who received intravenous/oral therapy were treated, overall, for an average of 8.6 +/- 3.6 days, with an average of 4.0 +/- 3.0 days of oral treatment. CONCLUSIONS: These results demonstrate statistical equivalence between CIP/MTZ IV and IMI IV in both the intent-to-treat and valid populations. Conversion to oral therapy with CIP/MTZ appears as effective as continued intravenous therapy in patients able to tolerate oral feedings.

Abdomen↗

Duration of antibiotic treatment in surgical infections of the abdomen. The future: randomised prospective studies.

The important questions are: what is the most efficient, least costly, and least hazardous way of providing antimicrobial therapy to postoperative patients? These questions, and the answers, are integral to the practice of medicine. I discuss a few pitfalls associated with antibiotic studies and suggest potential solutions. I urge doctors interested in these problems to focus on establishing the hospital systems needed to provide continuous feedback, rather than sporadic information driven by collegial requests.

Anti-Bacterial Agents↗

Definition of the role of enterococcus in intraabdominal infection: analysis of a prospective randomized trial.

BACKGROUND: The role of enterococcus in intraabdominal infection is controversial. This study examines the contribution of enterococcus to adverse outcome in a large intraabdominal infection trial. METHODS: A randomized prospective double-blind trial was performed to compare two different antimicrobial regimens in combination with surgical or percutaneous drainage in the treatment of complicated intraabdominal infections. A total of 330 valid patients was enrolled from 22 centers in North America. RESULTS: In 330 valid patients, 71 had enterococcus isolated from the initial drainage of an intraabdominal focus of infection. This finding was associated with a significantly higher treatment failure rate than that of patients without enterococcus (28% versus 14%, p < 0.01). In addition, only Acute Physiology and Chronic Health Evaluation II score and presence of enterococcus were significant independent predictors of treatment failure when stepwise logistic regression was performed (p < 0.01 and < 0.03). Risk factors for the presence of enterococcus include age, Acute Physiology and Chronic Health Evaluation II, preinfection hospital length of stay, postoperative infections, and anatomic source of infection. There was no difference between the clinical trial treatment regimens with regard to overall failure, failure associated with enterococcus, or frequency of enterococcal isolation. CONCLUSIONS: This study is the first to report enterococcus as a predictor of treatment failure in complicated intraabdominal infections. This trial also identifies several significant risk factors for the presence of enterococcus in such infections.

Abscess↗

Failure of local and systemic bacterial clearance in rats with acute pancreatitis.

These studies were designed to investigate the ability of rats to clear subcutaneous bacterial abscesses following acute pancreatitis. Animals underwent subcutaneous injection of 1 x 10(9) Escherichia coli and Staphylococcus aureus and, 24 h later, were randomized into four groups to receive (A) an intravenous (i.v.) infusion of cerulein, (B) saline i.v., (C) ligation of the pancreatic head, or (D) sham ligation. After 12 h, abscess sizes were measured and blood was withdrawn for culture and assay amylase and endotoxin level assay. Animals were observed for an additional 12 h to record mortality. Both E. coli and S. aureus abscesses were larger in group C vs. group D, while only the E. coli lesion was larger in group A vs. group B. Bacteremia was detected in 60% of the animals in group A, 40% in groups B and D, and 100% in group C. Mortality was 80% in group C vs. 10% in all other groups. Amylase and endotoxin levels were higher in group C vs. all groups. In the second experiment rats were injected with bacteria as above. Four, twelve, and twenty-four hours later the abscesses were removed for quantitation of bacteria and histologic evaluation. At 24 h rats underwent procedure A, B, C, or D and the abscesses were excised 12 h later. Group C had a significantly higher number of viable bacteria inside the lesion compared to group D. Histology showed tissue necrosis and cellulitis not observed in group D. It is concluded that acute pancreatis causes failure of local and systemic bacterial clearance and that the incidence of bacteremia and mortality is proportional to the severity of the disease.

Abscess↗

Regulation of TNF-alpha receptor expression on human neutrophils by various cell activating factors.

Since tumor necrosis factor-alpha (TNF-alpha) has been implicated in a wide range of inflammatory states, we sought to examine the regulation of TNF-alpha receptors on human neutrophils (PMNs). We were particularly interested in the relationship of TNF-alpha binding characteristics to various known neutrophil-priming stimuli such as temperature, N-formylmethionyl-leucyl-phenylalanine (fMLP), phorbol myristate acetate (PMA), C5ades Arg, and human recombinant C5a (HrC5a). Competition binding studies indicated that there was no significant change in receptor number or affinity due to the temperature used for neutrophil isolation. PMNs isolated at 4 or 25 degrees C had a single class of receptors with a Kd of 83.1 +/- 3.3 vs 90.0 +/- 8.3 pmole/liter and a similar number of receptors, 1575 +/- 99 vs 1876 +/- 279 receptors/cell. However, when either group of isolated PMNs was further incubated in buffer at 37 degrees C for 15 min, a significant increase in Kd (4-37 degrees C, 147.9 +/- 23.7 pmole/liter; 25-37 degrees C, 165.2 +/- 29.2 pmol/liter) and a decrease in receptor number (4-37 degrees C, 1116 +/- 86 receptors/cell; 25-37 degrees C, 957 +/- 71 receptors/cell) were seen. To determine the effect of other activating substances such as fMLP, PMA, C5ades Arg, HrC5a, 4 degrees C isolated PMNs were used.(ABSTRACT TRUNCATED AT 250 WORDS)

Complement C5a↗

Alterations of neutrophil responses to tumor necrosis factor alpha and interleukin-8 following human endotoxemia.

Interleukin-8 (IL-8), a neutrophil chemoattractant and activating cytokine, has been implicated as a proinflammatory mediator in gram-negative sepsis. In vitro data support the notion of IL-8 as an endothelial adherence inhibitor. To evaluate this issue, we infused six volunteers with reference endotoxin and measured plasma levels of IL-8, neutrophil tumor necrosis factor alpha (TNF-alpha) receptors, TNF-alpha-induced adherence to fibronectin, and neutrophil chemotaxis to IL-8 and other attractants. We found that, at 3 h postinfusion, IL-8 but not TNF-alpha plasma levels were elevated. Neutrophils had shed L-selectin (mean channel fluorescence decrease, 79 +/- 9 to 49 +/- 7; P = 0.0625) and TNF-alpha receptors (decrease in number of receptors per cell, 1,596 +/- 340 to 574 +/- 93; P = 0.004). Cells were chemotactically desensitized to IL-8. TNF-alpha-induced adherence to fibronectin was suppressed from 69% +/- 5% of the phorbol myristate acetate response to 38% +/- 7% (P = 0.0154). These findings support the notion that release of IL-8 into the vascular space may be an in vivo mechanism for suppression of neutrophil accumulation at extravascular sites. L-Selectin loss would reduce the ability of neutrophils to adhere to activated endothelial cells. The specific loss of migratory response to IL-8 would impair neutrophil delivery to areas where IL-8 was the predominant chemoattractant. Loss of TNF-alpha-induced adherence to fibronectin would blunt those responses, including production of oxidants, capacitated by adherence.

Endotoxins↗

Principles of antibiotic therapy.

The primary development in the area of antibiotic treatment for surgical infections in the last 5 years has been the expanded clinical importance of beta-lactamases in the protection of Gram-negative organisms from previously active drugs. To counter this problem, a series of new antibiotic agents has been developed, including new cephalosporins, carbapenems, quinolones, and beta-lactamase inhibitors. This article describes the various beta-lactamases and their mechanisms of action, and details the activity of new antibiotic agents against resistant Gram-negative organisms. Recent information on the importance of combination therapy for patients with severe Gram-negative infections is reviewed. The use of optimized aminoglycoside dosing regimens, including once-a-day dosing, provides an additional strategy for treating serious Gram-negative infections.

Aminoglycosides↗

Antimicrobial prophylaxis for surgical wounds. Guidelines for clinical care.

Prophylactic administration of antibiotics can decrease postoperative morbidity, shorten hospitalization, and reduce the overall costs attributable to infections. Principles of prophylaxis include providing effective levels of antibiotics in the decisive interval, and, in most instances, limiting the course to intraoperative coverage only. Use in The National Research Council clean contaminated operations is appropriate and, in many instances, has been proven beneficial. Antibiotic prophylaxis is also indicated for clean operations, such as those involved with insertion of prosthetic devices, that are associated with low infection risk and high morbidity. Extension of antibiotic prophylaxis to other categories of clean wounds should be limited to patients with two or more risk factors established by criteria in the study of the efficacy of nosocomial infection control (SENIC) because the baseline infection rate in these patients is high enough to justify their use. Cefazolin (or cefoxitin when anaerobic coverage is necessary) remains the mainstay of prophylactic therapy. Selection of an alternate agent should be based on specific contraindications, local infection control surveillance data, and the results of clinical trials. Newer criteria for determining the risk of "site infection" (wound and intracavitary) are in evolution and may lead to modification of these recommendations over the next several years.

Anti-Bacterial Agents↗

Pathogenesis and management of Candida infection syndromes in non-neutropenic patients.

Infections due to Candida spp. are increasingly common. Despite a number of studies examining the characteristics of fungemic (non-neutropenic) patients, there are no prospective studies defining indications for therapy before the appearance of fungemia. This article reviews the potential pathways for dissemination of Candida from the gastrointestinal tract, believed to be the primary entry route for yeast. Particular attention is focused on mucosal shedding at the villous tip and the potential role of microfold cells in this process. Therapeutic usage of amphotericin B, the agent of choice for serious Candida infection, is reviewed, along with usage of 5-flucytosine and fluconazole.

Amphotericin B↗

Guidelines for clinical care: anti-infective agents for intra-abdominal infection. A Surgical Infection Society policy statement.

Several antibiotics have been marketed for therapeutic use in intra-abdominal infection. Often, these agents do not provide a sufficient spectrum activity against both facultative and obligate anaerobic gram-negative organisms, or have certain toxic effects that would not otherwise support their use. Guidelines have been developed for selection of antibiotic therapy for intra-abdominal infections and are presented as a statement of the Surgical Infection Society endorsed by the Executive Council. These guidelines are restricted to infections derived from the gastrointestinal tract and deal with those microorganisms commonly seen in such infections. The recommendations are based on in vitro activity against enteric bacteria, experience in animal models, and documented efficacy in clinical trials. Other concerns regarding pharmacokinetics, mechanisms of action, microbial resistance, and safety were also used in the formation of these guidelines. For community-acquired infections of mild to moderate severity, single-agent therapy with cefoxitin, cefotetan, or cefmetazole or ticarcillin-clavulanic acid is recommended. For more severe infections, single-agent therapy with carbapenems (imipenem/cilastatin) or combination therapy with either a third-generation cephalosporin, a monobactam (aztreonam), or an aminoglycoside plus clindamycin or metronidazole is recommended. Regimens with little or no activity against facultative gram-negative rods or anaerobic gram-negative rods are not considered acceptable.

Abdomen↗

Evaluation of new anti-infective drugs for the treatment of intraabdominal infections. Infectious Diseases Society of America and the Food and Drug Administration.

These guidelines deal with the evaluation of anti-infective drugs for the treatment of intraabdominal infections. The clinical entities consist of infections arising from any part of the gastrointestinal tract, from the distal esophagus to the colon. These include surgical infections of the bowel, biliary tree, liver, spleen, and pancreas. Virtually all intraabdominal infections are due to multiple microorganisms resident in the gastrointestinal tract; these include aerobes and facultative and obligate anaerobes. Infections are classified as complicated (requiring an operative procedure), uncomplicated (managed medically), and postoperative wound (the operative procedure should be curative, but anti-infective drugs are used to prevent further infection at the site). Clinical criteria are paramount for entry into a study and for evaluation of efficacy. For complicated infections an adequate operation is an important determinant of outcome and needs assessment. Cultures of purulent intraabdominal fluid or abscess material are the only valid microbiologic indicators of infection. The acute physiology and chronic health evaluation score is useful in defining the severity of acute illness. The control regimen should consist of effective, established drugs and surgical procedures for the condition. Duration of therapy for complicated infections is usually 5-14 days; for uncomplicated infections, 3-7 days; and for postoperative wound infection, 2-5 days. Periodic assessment of safety and efficacy must be conducted during therapy. The outcome at final assessment is cure, failure, or indeterminate.

Anti-Infective Agents↗

Evaluation of new anti-infective drugs for the treatment of acute pelvic infections in hospitalized women. Infectious Diseases Society of America and the Food and Drug Administration.

This set of guidelines deals with evaluation of anti-infective drugs for treatment of acute pelvic infections in hospitalized women. The clinical entities include infectious complications of cesarean section; elective hysterectomy; and septic, incomplete abortion. Conditions including endomyometritis, cuff cellulitis, pelvic cellulitis, parametritis, phlegmon, and pelvic abscesses may arise due to a variety of bacterial species, both aerobic and anaerobic, that comprise the endogenous flora of the lower reproductive tract. Anaerobic bacteria have assumed particular importance, and therapy should be directed against such organisms. The roles of enterococci, chlamydiae, and mycoplasmas remain uncertain. Culture samples must be obtained under conditions assuring minimal vaginal contamination. Before a new drug may be used for treatment of human pelvic infections, considerable information is necessary about its antimicrobial spectrum as well as its safety and efficacy. Placebo-controlled trials are considered unethical. Historical controls may be used, but concurrent active control comparative trials are preferred. Parenteral administration is recommended for at least the initial 4 days of therapy, but orally administered drugs may be evaluated for completion of longer courses. The expected cure rate is approximately 90%. Uncomplicated infections should be treated for at least 4 days; more complicated infections may require prolonged therapy. Although clinical cure is paramount, microbiologic response must also be taken into account. In the final assessment, outcome will be classified as cure, failure, or indeterminate.

Acute Disease↗

Evaluation of new anti-infective drugs for the treatment of acute pelvic inflammatory disease. Infectious Diseases Society of America and the Food and Drug Administration.

Pelvic inflammatory disease (PID) is a syndrome unrelated to pregnancy or surgery and characterized by lower abdominal pain and tenderness, cervical motion tenderness, and adnexal tenderness. Fever, leukocytosis, and the results of laboratory tests are used to support the diagnosis. Participants in clinical trials should be stratified into two groups: those with and those without tubo-ovarian abscess--i.e., those with complicated and those with uncomplicated PID. Diagnostic studies and treatment should be directed at four major groups of pathogens: Neisseria gonorrhoeae, Chlamydia trachomatis, anaerobic bacteria, and facultative bacteria such as Escherichia coli. Women requiring hospitalization should generally be treated as inpatients for at least 4-7 days; outpatient therapy should then be instituted to complete a 14- to 21-day course. Clinical and laboratory evaluations should be conducted daily during hospitalization and both 2-4 days and 2-4 weeks after the completion of therapy.

Acute Disease↗

Activation of neutrophils by cachectin/tumor necrosis factor: priming of N-formyl-methionyl-leucyl-phenylalanine-induced oxidative responsiveness via receptor mobilization without degranulation.

Human recombinant cachectin/tumor necrosis factor (TNF) was shown to prime neutrophils (PMNs), in a dose-dependent fashion, for subsequent oxidative responsiveness toward n-formyl-methionyl-leucyl-phenylalanine (FMLP). One basis for this phenomenon appeared to be TNF-mediated FMLP receptor mobilization. The maximal observed priming response was associated with a nearly twofold increase in the expression of PMN FMLP surface receptors, without changes in receptor affinity. Priming was not seen following stimulation with phorbol myristate acetate, possibly eliminating a role for the protein kinase C-dependent transductional components of FMLP-induced oxidative activity in the priming process. FMLP receptor mobilization occurred without significant degranulation as evident by an absence of increased granular enzyme release. These data support a potential role of macrophage-derived TNF in the augmentation of PMN host-defense during infectious and inflammatory challenge. TNF-mediated PMN oxidative priming may also promote oxidant tissue injury as seen in septic shock, adult respiratory distress syndrome, and multiple system organ failure.

Adult↗

Complement activation and lung permeability during cardiopulmonary bypass.

Pulmonary dysfunction after cardiopulmonary bypass has been attributed to the damaging effects of complement activation on the lung. To further explore this phenomenon, we measured plasma levels of activated complement components (radioimmunoassay), assessed neutrophil n-formyl-methionyl-leucyl-phenylalanine (FMLP) receptor status (radioligand saturation binding assay), and quantified pulmonary epithelial permeability as radioaerosol lung clearance of technetium 99m-labeled diethylenetriamine pentaacetic acid in a series of 8 patients undergoing cardiopulmonary bypass. Significant elevations of plasma C3adesArg, C4adesArg, and C5adesArg levels were seen just after CPB, indicating activation of both the classic and alternate complement pathways. Neutrophil activation was evident as increased expression of neutrophil FMLP surface receptors after bypass. Despite the presence of complement and neutrophil activation, increased pulmonary epithelial permeability was not seen. These data support the hypothesis that complement and neutrophil activation during cardiopulmonary bypass is not associated with acute lung injury, at least not pulmonary epithelial injury. One can therefore infer that increased pulmonary epithelial permeability in patients at high risk for and experiencing sepsis-induced and trauma-induced adult respiratory distress syndrome may be due to factors other than complement and neutrophil activation.

Capillary Permeability↗

Results of a multicenter trial comparing imipenem/cilastatin to tobramycin/clindamycin for intra-abdominal infections.

We designed a multicenter study to compare tobramycin/clindamycin to imipenem/cilastatin for intra-abdominal infections. We included the Acute Physiology and Chronic Health Evaluation (APACHE II) index of severity and excluded patients without established infection. Two hundred ninety patients were enrolled, of whom 162 were evaluable. Using logistic regression to analyze both outcome at the abdominal site of infection and outcome as mortality, we found a significant correlation for both with APACHE II score (p less than 0.0001 for both). Next we analyzed the residual effect of treatment assignment and found a significant improvement in outcome for imipenem/cilastatin-treated patients (p = 0.043). The differences in outcome were explained by a higher failure rate for patients with gram-negative organisms for tobramycin/clindamycin-treated patients (p = 0.018). This was reflected in a significantly higher incidence of fasciitis requiring reoperation and prosthetic fascial replacement. Maximum peak tobramycin levels were analyzed for 63 tobramycin/clindamycin patients harboring gram-negative organisms. For failures the maximum peak was 6.4 +/- 1.9 micrograms/mL, and time to maximum peak was 4.6 +/- 5.2 days. For successes the maximum peak was 6.1 +/- 1.7 micrograms/mL, occurring at 3.8 +/- 2.6 days. This study supports inclusion of severity scoring in statistical analyses of outcome results and supports the notion that imipenem/cilastatin therapy improves outcome at the intra-abdominal site of infection as compared to a conventionally prescribed amino-glycoside-based regimen.

Abscess↗