Role of amikacin in the management of intra-abdominal sepsis.

Controversy has developed regarding the antibiotic management of intra-abdominal sepsis because of the recent availability of the third-generation cephalosporins and ureidopenicillins as alternatives to traditional combination therapy (aminoglycosides plus clindamycin). Most observers now acknowledge the need to provide anti-anaerobic as well as anti-aerobic gram-negative drug coverage. Although most of the newer agents do provide such broad-spectrum coverage, doubt remains regarding their efficacy because of flaws in comparative study design and the observation that resistance to the newer agents, which may even extend to the aminoglycosides, can emerge in individual patients during single courses of antibiotic therapy. Indeed, such resistance is most likely to occur during the treatment of seriously ill, immunodepressed patients who have undergone multiple reoperation for persistent or recurrent intra-abdominal sepsis--the precise group for which the new drugs were most desired as less toxic alternatives to the aminoglycosides. On the basis of such observations, combination therapy with the aminoglycosides, appears to remain the most logical choice. In the setting of nosocomial sepsis and pathogen resistance to other aminoglycosides, amikacin may be especially effective. Recent surveillance data indicate that the use of amikacin under such circumstances not only may provide effective antibiotic therapy, but also may actually reduce the level of microbial resistance to the other aminoglycosides. Past concern regarding the development of resistance to amikacin has probably been excessive and should not deter the use of this agent under appropriate clinical circumstances.

Endogenous factors contributing to prosthetic device infections.

Although there is a direct association between the tissue reactivity of implants and their ability to potentiate infection, bacterial slime production and adherence to implant surfaces (generation of the biofilm) appear to play a primary role in the pathogenesis of most prosthesis infections.

'Breakthrough' enterococcal septicemia in surgical patients. 19 cases and a review of the literature.

We studied 19 surgical patients with 24 postoperative episodes of enterococcal septicemia not arising from the biliary or urinary tracts or from infected heart valves. Fifteen episodes occurred despite the administration of broad-spectrum antibiotics; in only one patient were these drugs effective against enterococcus. There were 14 episodes of enterococcemia in 11 patients following which the patient survived for at least one week. Thirteen (93%) of those episodes were treated with either ampicillin or drainage, or both. Five of the six long-term survivors received ampicillin therapy. Overall mortality was 68%. The data suggest that the enterococcus may emerge as a blood-borne pathogen in immunodepressed, postoperative patients receiving antibiotics for other infections of enteric origin. Antibiotic therapy specifically directed against this organism (and surgical drainage, if necessary) may be indicated during polymicrobial sepsis of enteric or mixed origin. If the spectrum of antibiotics does not include enterococcus, this organism can cause "breakthrough" sepsis, as can many other opportunistic organisms.

Stomach cancer following gastric surgery for benign disease.

The records of 1,079 patients with gastric carcinoma were reviewed. Of these, only 21 (about 2%) had had previous gastric surgery for benign disease, usually peptic ulcer. The average interval between the original gastric surgery and the discovery of stomach cancer was 26.9 years. The symptoms of cancer presentation were not distinguishable from other forms of the postgastrectomy syndrome. Gastric cancer tended to develop in these patients during the sixth decade of life, irrespective of when they had had their original gastric surgery, strongly suggesting an age-related factor. Although it would appear that previous gastric surgery for benign disease is not a major risk factor for the subsequent development of gastric cancer, such a relationship may exist. Patients who have undergone gastrectomy should be followed up carefully for the recurrence of symptoms.

Perforated or gangrenous appendicitis treated with aminoglycosides. How do bacterial cultures influence management?

To study the influence of bacterial culture data on the clinical management of gangrenous or perforated appendicitis, we reviewed records of 104 patients who had been treated empirically with aminoglycoside antibiotics. Culture results appeared to influence antibiotic therapy in only 7 patients (7%). The routine cultures obtained at appendectomy affected therapy in only 2 patients. Discriminant analysis identified postoperative infectious complications and related factors as the principal determinants of culture utility. We conclude that, in patients with perforated appendicitis treated empirically with aminoglycoside combination regimens, culture results were seldom used for clinical management except in instances of postoperative infectious complication. Routine cultures and Gram's stains of perforated appendicitis, however, should still be obtained (1) to allow epidemiologic tracking in the hospital; (2) to identify organisms that are recovered infrequently but may cause serious disease (eg, Clostridium); and (3) because newer antibiotics are replacing aminoglycosides in the treatment of perforated appendicitis.

Assessment of hepatitis B virus immunization status among North American surgeons.

OBJECTIVE: We hypothesized that many surgeons have not been vaccinated against hepatitis B virus (HBV), despite the existence of effective recombinant vaccines. Prevalence of HBV vaccination among surgeons, attitudes of those not vaccinated, estimated HBV infection rates, and respondents' knowledge of the epidemiology of HBV exposure were determined. DESIGN: Survey conducted by mail just before implementation of mandatory HBV vaccination for health care workers. SETTING: Private and academic general surgical, trauma and transplantation practices. PARTICIPANTS: Two thousand one hundred twenty-five surgeons received the survey. Response rates are as follows: in the Surgical Infection Society, 196 (50%) of 393 surgeons; in the American Association for the Surgery of Trauma, 223 (52%) of 433 surgeons; in the American Society of Transplant Surgeons, 194 (44%) of 438 surgeons; and among the Fellows of the American College of Surgeons, 403 (47%) of 861 surgeons. MAIN OUTCOME MEASURES: Prevalence of HBV exposure and active immunization by specialty and society. RESULTS: Prevalence of HBV exposure was 19.6%, was higher among trauma and transplantation surgeons compared with general surgeons (P < .0001), and increased significantly with age in all groups (P < .05). Despite greater exposure, probable immunity was lower at an older age because young surgeons (age, < 46 years) are more likely to be vaccines (P < .05). Most surgeons (55%) were vaccinated more than 5 years ago; many recipients of recombinant vaccines (26%) received an inadequate amount of vaccine or were improperly vaccinated. Knowledge of the epidemiology was uniformly poor, with rates of correct responses to the three questions below 50%. CONCLUSIONS: Vaccination does not equal immunity. Between 38% and 50% of practicing surgeons may not have adequate immunity to HBV.

Role of enterococcus in intraabdominal sepsis.

Although enterococcus is well recognized as a pathogen in endocarditis, urinary tract infections, and biliary sepsis, its role in other forms of intraabdominal sepsis remains controversial. Antibiotics that lack activity against enterococcus can often be employed successfully in intraabdominal infections, even when enterococci are present as part of the polymicrobial flora. Furthermore, the enterococcus rarely emerges as a blood borne pathogen in such a setting. Breakthrough enterococcal septicemia may occur, however, in the immunodepressed host, particularly in the face of broad-spectrum antibiotic therapy not specific for enterococcus. Like infections with other opportunistic pathogens, enterococcal sepsis under these circumstances carries a high mortality. Specific antienterococcal drug therapy may be indicated as an adjunct to surgical management in selected patients with intraabdominal sepsis.

Amebic liver abscess. Differential diagnosis of cholecystitis.

Among patients presenting with pain and tenderness in the right upper quadrant were 75 with cholelithiasis (13 male, 2 under age 50) and 9 with amebic hepatic abscess (6 male, all under age 45). The differential diagnosis of cholelithiasis versus liver abscess was accurately made by prompt sonography and hepatobiliary scintigraphy. Amebic abscess was confirmed by positive serum ameba titers. Presenting symptoms and results of laboratory studies of patients with amebic abscess were indistinguishable from those of patients with cholecystitis. It is concluded that an accurate diagnosis of amebic liver abscess in the differential diagnosis of cholecystitis can be made by sonography and hepatobiliary imaging. Also, in endemic areas of the southwestern United States, amebic abscess should be strongly considered in the differential diagnosis of patients presenting with pain and tenderness in the right upper quadrant and is more common than cholecystitis in young men.

Effects of soil infection potentiating factors on neutrophils in vitro.

Although the ability of soil silicate fractions to potentiate infection is well recognized, the precise mechanisms by which they do so remain unexplained. This study was carried out to investigate the effects of montmorillonite clay, the most potent of these soil infection potentiators, on human neutrophils, erythrocytes, and serum complement in vitro. Using phase microscopy, rapid neutrophil lysis was observed when cells were exposed to untreated clay. After lysis, the cytoplasmic marker enzyme lactate dehydrogenase rapidly adsorbed to the surface of the clay. Both enzyme surface adsorption and cell lysis could be blocked, however, by pretreatment of the clay with human albumin. Likewise, neutrophil chemiluminescence could be stimulated by untreated clay, but not by clay pretreated with 5 percent albumin or 10 percent pooled human serum. Maximal chemiluminescence was stimulated by clay pretreated with 0.1 percent albumin, probably because the partially protective albumin coating delayed cell lysis. Compared with the effect on neutrophils, clay lysis of erythrocytes was incomplete. When zymosan-activated serum samples were exposed to clay, complement activity as measured by neutrophil chemotaxis was suppressed in a dose-dependent fashion. We conclude that montmorillonite clay may potentiate infection by a direct cytotoxic effect on the neutrophil, making it unavailable for bacterial phagocytosis, by local reduction in bacterial opsonization due to depletion of activated complement, and by the release of toxic tissue substances, such as lysosomal enzymes and oxygen free radicals, from leukocytes which may damage host tissue and thus create an environment favorable for bacterial survival.

Early surgery for biliary pancreatitis.

Herein, we documented our successful experience in performing definitive biliary tract surgery on patients with biliary pancreatitis as soon as the diagnosis was made and within 48 hours of admission. Early surgery reduced the length of hospital stay and did not result in associated morbidity, death, or complications of acute pancreatitis. The results of the study support the concept that removing obstruction of the pancreatic duct prevents progression of edematous pancreatitis to hemorrhagic pancreatitis. We conclude that patients with acute pancreatitis should be evaluated urgently for the presence of biliary tract stone disease and should be operated on as soon as the diagnosis of biliary pancreatitis is made, that early definitive surgery can be performed safely on patients with biliary pancreatitis, that cholecystectomy with intraoperative cholangiography and common duct exploration as necessary should be performed in all patients, and that length of stay for patients with biliary pancreatitis is reduced and morbidity and mortality possibly may be reduced by early surgery as compared with delayed surgery.

The drain-tract sinogram. Guide to the removal of drains and the diagnosis of postoperative abdominal sepsis.

Sinography via previously established abdominal drains or tracts from which drains had been removed may be useful in the diagnosis of postoperative intra-abdominal sepsis. Six cases are presented in which drain tract sinograms with water-soluble contrast facilitated the diagnosis of otherwise cryptic intra-abdominal abscesses, retroperitoneal abscesses, or enteric leaks. In addition, repeated drain tract sinograms can be used to determine the proper timing of intra-abdominal drain removal and may avoid the septic complication of drain removal in cases of residual intra-abdominal sepsis or undiagnosed enterocutaneous fistula.

Cefamandole versus cefoxitin prophylaxis in patients undergoing cholecystectomy.

A prospective, randomized, double-blind study of three different antibiotic prophylaxis regimens in 150 patients undergoing cholecystectomy was conducted. Group I patients received a 1-gram preoperative dose of cefamandole followed by 4 additional postoperative doses at 6-hour intervals. Group II received a similar regimen except that 2-gram doses of cefamandole were used. Group III received a comparable cefoxitin regimen in 2-gram doses. The patients were deemed to be at high risk for postoperative infection by virtue of the fact that most (almost 70%) were obese and all had had a recent attack of cholecystitis. There were no significant differences among the 3 groups with respect to postoperative infectious complications. It is concluded that perioperative cefamandole and cefoxitin are both effective in reducing the postoperative infectious complications of cholecystectomy. A 5-gram course of cefamandole is as effective as either a 10-gram course of cefamandole or a 10-gram course of cefoxitin and could provide a substantial savings in cost.

Ticarcillin/clavulanate compared with clindamycin/gentamicin (with or without ampicillin) for the treatment of intra-abdominal infections in pediatric and adult patients.

Combinations of penicillins with beta-lactamase inhibitors have become acceptable treatments for mixed bacterial infections. The objective of this multicenter, randomized, open-label study was to compare the efficacy, safety, and tolerance of ticarcillin/clavulanate with clindamycin/gentamicin (with or without ampicillin) when administered to adult and pediatric patients with intra-abdominal infections. A total of 993 patients 2 years of age or older were entered in this trial if they had suspected or bacteriologically documented intra-abdominal infection. Of these, 341 were determined at the time of operation to have intra-abdominal infection. Cure rates at the time of final assessment were 79%, 80%, and 82% for ticarcillin/clavulanate, and clindamycin/gentamicin without or with ampicillin, respectively (P = 0.829, Cochran-Mantel-Haenszel). The most frequent reason for failure was development of an intra-abdominal abscess (6% of patients overall), followed by wound infections (4%), and persistent fever (3%). Two patients who had received ticarcillin/clavulanate and five who had received clindamycin/gentamicin required discontinuation of the study regimen because of adverse drug reactions. The bacteria isolated most frequently from study failures were E. coli, B. fragilis, Pseudomonas, and Streptococci. In this study, ticarcillin/clavulanate was as effective as the combination of clindamycin/gentamicin for the treatment of intra-abdominal infections.