Portal vein thrombosis.

Portal vein thrombosis (PVT) is a complication of hepatic disease and a potentially lethal complication of splenectomy. The reported incidence of this complication is low (approximately 1%). However, its true incidence may have been underestimated due to difficulty in making the diagnosis. Herein we report the case of a 19 year-old woman who presented with a 2-year history of idiopathic thrombocytopenic purpura (ITP). Because she had become refractory to medical therapy, she underwent laparoscopic splenectomy. She was discharged on postoperative day 2 after an uncomplicated procedure. She did well, complaining only of mild backache, until postoperative day 21, when she presented with nausea, vomiting, and leukocytosis. CT showed PVT and superior mesenteric vein thrombosis. Despite heparin and fluid administration, her condition worsened. At laparotomy, she had diffuse small bowel edema and congestion. At a second-look procedure 24 h later, nearly all her jejunum and ileum were necrotic. After three procedures, she was left with 45 cm of proximal and 10 cm of distal small bowel. Bowel continuity was restored 8 weeks later. She continued on warfarin anticoagulation therapy for 1 year. Postsplenectomy PVT is most often seen following splenectomy for myeloproliferative disorders and almost never after trauma. The large splenic vein stump and the hypercoagulable state in patients with splenomegaly are thought to be contributory. The presentation of PVT is vague, without defining signs or symptoms. Color-flow Doppler and contrast-enhanced CT scans are the best methods for the nonoperative diagnosis of PVT. Aggressive thrombolysis offers the best hope for clot lysis and maintenance of bowel viability. Even vague symptoms must be considered seriously following splenectomy.

Wound infection after infrainguinal bypass operations: multivariate analysis of putative risk factors.

Reported wound infection rates for infrainguinal bypass operations range from 17% to 44%, but there is limited appreciation of which characteristics of patients or operations are reliable markers of increased wound infection risk. The purpose of the present study was to analyze all wound infections observed after infrainguinal bypass operations during 20 years of practice in a large teaching institution. Independent risk factors for wound infection development were identified. During the 20-year period ending 31 December, 1997, 978 male patients underwent infrainguinal bypass operations at the Minneapolis Department of Veterans Affairs Medical Center. Wound infections complicated the recovery of 129 of these patients during a 30-day postoperative surveillance interval. Multivariate logistic regression analysis was used to test the association between wound infection occurrence and putative risk factors that were either features of patients or characteristics of the operations. The following variables were examined: obesity, prosthetic graft placement, diabetes mellitus, steroid use, anticoagulation use, length of preoperative hospital stay, development of incisional hematoma, duration of operation, and the preoperative presence of a non-healing wound in the extremity being revascularized. The overall wound infection rate was 13.2% (129/978). In a final logistic regression model, obesity was a significant and independent predictor of wound infection (Relative Risk 2.6, 95% confidence interval, 1.35-4.90), as was development of a post-operative incisional hematoma (Relative Risk 6.44, 95% confidence interval, 2.95-14.08). No other explanatory variable was significantly associated with wound infection development.

Basolateral amiloride-sensitive Na+ transport pathway in rat tongue epithelium.

1. Experiments were conducted to test for the presence of basolateral Na+ channels in the rat lingual epithelium. Researchers have proposed a model in which some lingual taste cells have Na+ channels in the basolateral membrane. That model is designed to account for the portion of the neural taste response and the portion of the transepithelial short-circuit current (Isc) in vitro that are insensitive to mucosal amiloride; some Na+ would diffuse across the tight junction into the cell via this lateral pathway, and would be transported out of the cell by Na+ pumps in the basal membrane. The model could also account for the differential effect of mucosal amiloride on Na+ salts of various anions, in which the neural taste responses to Na+ salts with anions larger than Cl- are more sensitive to mucosal amiloride than is the taste response to NaCl. 2. Voltage-clamp data were obtained from an in vitro preparation of the anterior-dorsal rat tongue epithelium in which the connective tissue was removed by enzyme digestion. Isc in a modified Ussing chamber was reduced by amiloride in the submucosal solution. 3. The pattern of sensitivity to submucosal amiloride differed in several respects from the pattern for mucosal amiloride. The inhibition constant (Ki) was 52 microM amiloride concentration, higher than for the apical amiloride-sensitive Na+ channel. The selectivity for Na+ over K+ was much less than for the response to mucosal amiloride; with 0.5 M NaCl or KCl on the mucosal side, the ratio of inhibition for the NaCl response to inhibition for the KCl response varied between 1 and 3. 4. As the concentration of NaCl in the mucosal solution was varied, submucosal amiloride caused little inhibition of Isc for mucosal NaCl below isosmotic concentration, with the percent inhibition increasing as mucosal salt concentration increased. With 0.5 M sodium gluconate in the mucosal solution, there was very little inhibition due to submucosal amiloride. 5. The results support the presence of amiloride-sensitive Na+ channels in the basolateral membranes of the dorsal tongue epithelium in rat, and are consistent with the proposed model in which these channels are present in taste cells.

Ten years of prospective Clostridium difficile-associated disease surveillance and treatment at the Minneapolis VA Medical Center, 1982-1991.

OBJECTIVES: To understand the epidemiology, risks, and management of Clostridium difficile-associated disease (CDAD) and to establish and evaluate reliable methods of surveillance. DESIGN: Case finding was done by daily ward and laboratory rounds. The criteria for CDAD diagnosis were: at least four unformed stools per day for 2 days and a positive culture or cytotoxin for C difficile, or positive endoscopy or autopsy for pseudomembranes. SETTING: The surveillance covered all patients from 1982 through 1991 in the 820-bed Minneapolis Veterans Affairs Medical Center. PARTICIPANTS: The criteria were met by 908 patients. Medical service patients numbered 488; surgical patients, 420. Frequencies ranged from a high of 149 cases in 1982 to a low of 50 cases in 1989. RESULTS: Stool specimens were obtained on 898 (99%) of the 908 CDAD patients. Stools were culture-positive in 864 (96%) of 898, cytotoxin-positive in 569 (63%) of 898. Endoscopy was performed on 196 (22%) of the 908 patients, and 80 (41%) of 196 patients had pseudomembranes. Ten (1%) of the 908 patients were diagnosed by endoscopy without a stool specimen, or at autopsy. No treatment was needed for 135 (15%) of the 908 CDAD patients, and 19 (2%) of the 908 died before treatment was started. Oral metronidazole was the treatment for 632 (70%) of 908 patients (1% intolerance, 2% failure, 7% relapse) and oral vancomycin was given to 122 (13%) of 908 patients (1% intolerance, 1% failure, 10% relapse). Twelve patients had pseudomembranous colitis at autopsy, and it was the primary cause of death in 5 (0.6%) of 908. CONCLUSIONS: CDAD usually responds to oral metronidazole or vancomycin but is nonetheless responsible for a high morbidity and occasional mortality in patients even when the diagnosis and treatment are pursued aggressively.

A fifteen-year wound surveillance study after coronary artery bypass.

Wound infections after coronary artery bypass operations have been continuously monitored at the Minneapolis Veterans Affairs Hospital for 15 years. All patients were followed up for 30 days. From 1977 to 1991, 2,402 coronary artery bypass operations were performed, and wound infections developed in 125 (5%) patients. There were 71 (3%) chest infections of which 33 (1.4%) were major and 38 (1.6%) superficial. Greater than 94% of these grew only a single organism, of which 74% were Staphylococcus species. There were 63 (2.6%) leg wound infections. More than 50% of these grew multiple organisms, of which 68% were enteric in origin. Nine (0.4%) patients had simultaneous chest and leg infections. Wound infections were diagnosed an average of 15.3 +/- 6.7 (range, 4 to 30) days postoperatively, with 50% occurring after discharge from the hospital. Of 14 variables evaluated by multivariate logistic regression analysis, only steroids (p = 0.005) and diabetes (p = 0.003) were identified as independent risk factors for wound infections. Patients taking steroids or with diabetes tended to have chest infections, whereas obese patients tended to have more leg infections (p = 0.08). During an interval in the surveillance program, a trend toward increasing infections was identified and successfully reversed.

Acquisition of Clostridium difficile by hospitalized patients: evidence for colonized new admissions as a source of infection.

The frequency of introduction and spread of specific Clostridium difficile strains among hospitalized patients were assessed by serial cultures of patients admitted to a medical-surgical ward with endemic C. difficile-associated diarrhea. Stool cultures were obtained from 634 (94%) of 678 consecutive admissions to the ward (ward admissions), and all C. difficile isolates were typed by restriction endonuclease analysis. Sixty-five ward admissions introduced C. difficile to the ward, and 54 initially culture-negative admissions acquired C. difficile on the ward. Ward admissions hospitalized within the prior 30 days in the medical center were more likely to be culture-positive for C. difficile at admission to the study ward than those not previously hospitalized at the institution (16% vs. 7%, P less than .001). Nosocomial acquisition of a C. difficile strain was preceded by a documented introduction of that strain to the ward by another asymptomatic ward admission in 16 (84%) of 19 instances, suggesting that C. difficile-colonized new admissions are a major source of nosocomial C. difficile infections.

Comparison of the VIDAS Clostridium difficile toxin A immunoassay with C. difficile culture and cytotoxin and latex tests.

The VIDAS Clostridium difficile toxin A immunoassay (CDA) is a new, automated, enzyme-linked fluorescent-antibody assay for detection of C. difficile toxin A antigen in stool specimens. Simultaneous, parallel testing was performed by using the VIDAS CDA, the Culturette brand CDT latex test for C. difficile antigens, and conventional laboratory cell culture tests for C. difficile, cytotoxicity and C. difficile culture. One hundred ninety-four consecutive fresh soft or liquid stool samples submitted for C. difficile testing between July and September 1990 were evaluated. Of the 194 samples tested, 19 (10%) were from 16 patients who met our case definition for C. difficile-associated disease. The in vitro tests were evaluated in relation to two forms of a clinical case definition. In one form, a positive culture for toxin-producing C. difficile or a positive cytotoxin result obtained directly from the stool specimen was required as laboratory evidence of C. difficile. In the other, a positive result of any of the four laboratory tests was accepted for the laboratory portion of the case definition. No significant difference between the sensitivity of the VIDAS CDA and that of the Culturette brand CDT latex test was found (48 to 58% sensitivity for the CDT latex test and 52 to 63% sensitivity for the VIDAS CDA compared with 93 to 100% sensitivity for culture and 70 to 100% sensitivity for cytotoxin testing). The performance of the VIDAS CDA, however, was hampered by a high percentage of tests (19%) which gave an uninterpretable result.

Quality of life of community mental health program clients: validating a measure.

A quality of life theory is proposed as a framework for conceptualizing and evaluating mental health services. Quality of life consists of fulfilling needs, meeting social expectations, and accessing opportunities by using abilities. Abilities are impaired by mental illness. Mental health services moderate social demands, supplement opportunities, and restore abilities. A 263 item questionnaire was developed to assess the impact of mental health services on clients' quality of life. A 24 site study including 1,154 pre-tests, 758 post-tests, and 190 interviews with randomly selected community residents was conducted. Evidence for the reliability and validity of the questionnaire are presented. The instrument discriminates among four known client groups, client and community samples, communities with known quality of life differences, and pre- versus post-treatment samples of clients. The convergence between client's retrospective impressions of improvement and measured pre-post improvement is discussed.

Nosocomial Clostridium difficile colonisation and disease.

To assess the risk of acquiring Clostridium difficile diarrhoea or colitis in patients colonised with C difficile, rectal swabs taken weekly for 9 weeks from patients with long-term (at least 7 days) hospital stays on three wards were cultured for C difficile. 60 (21%) of 282 patients were culture-positive for C difficile during their hospital stay, of whom 51 were symptom-free faecal excretors. C difficile diarrhoea developed in the other 9 patients; 2 were culture-positive for C difficile and had diarrhoea at the time of first culture, and 7 had diarrhoea or pseudomembranous colitis after 1-6 previously negative weekly rectal cultures. All patients with diarrhoea were on one ward, but symptom-free, excretors were found on all wards. HindIII chromosomal restriction endonuclease analysis (REA) of the C difficile isolates revealed 18 distinct types. All isolates from the patients with diarrhoea were one of two nearly identical REA types, B or B2. 26 of the 29 total B/B2 isolates were from patients on the same ward, which points to a nosocomial outbreak. The symptom-free excretors were not at increased risk of subsequent clinical illness.

Continuous, 10-year wound infection surveillance. Results, advantages, and unanswered questions.

During a 10-year wound infection surveillance program, 1032 wound infections complicated 40,915 operations. Surveillance continued for 30 days postoperatively, and rigid clinical criteria for diagnosis were honored. Operations were distributed unequally among infection risk classes: clean (class I), 63.3%; clean contaminated (class II), 26.4%; and contaminated (class III), 10.3%. Infections occurred with nearly equal frequencies among classes: I, 36.1%; II, 29.5%; and III, 34.4%. Wound infection rates during the 10-year period were 2.5% (all operations), 1.4% (class I), 2.8% (class II), and 8.4% (class III). Index year (1977) infection rates were 4.2% (all operations), 2.3% (class I), 5.4% (class II), and 12.8% (class III). Wound infection rates during the last 9 years of surveillance in every risk class were significantly less than index year rates, representing infection rate decreases of 38% to 56%. Estimated savings in hospital room costs alone reached $3 million during 10 years.

Prospective, controlled study of vinyl glove use to interrupt Clostridium difficile nosocomial transmission.

PURPOSE: Despite recognition that Clostridium difficile diarrhea/colitis is a nosocomial infection, the manner in which this organism is transmitted is still not clear. Hands of health care workers have been shown to be contaminated with C. difficile and suggested as a vehicle of transmission. Therefore, we conducted a controlled trial of the use of disposable vinyl gloves by hospital personnel for all body substance contact (prior to the institution of universal body substance precautions) to study its effect on the incidence of C. difficile disease. PATIENTS AND METHODS: The incidence of nosocomial C. difficile diarrhea was monitored by active surveillance for six months before and after an intensive education program regarding glove use on two hospital wards. The interventions included initial and periodic in-services, posters, and placement of boxes of gloves at every patient's bedside. Two comparable wards where no special intervention was instituted served as controls. RESULTS: A decrease in the incidence of C. difficile diarrhea from 7.7 cases/1,000 patient discharges during the six months before intervention to 1.5/1,000 during the six months of intervention on the glove wards was observed (p = 0.015). No significant change in incidence was observed on the two control wards during the same period (5.7/1,000 versus 4.2/1,000). Point prevalence of asymptomatic C. difficile carriage was also reduced significantly on the glove wards but not on the control wards after the intervention period (glove wards, 10 of 37 to four of 43, p = 0.029; control wards, five of 30 to five of 49, p = 0.19). The cost of 61,500 gloves (4,505 gloves/100 patients) used was $2,768 on the glove wards, compared with $1,895 (42,100 gloves; 3,532 gloves/100 patients) on the control wards. CONCLUSIONS: Vinyl glove use was associated with a reduced incidence of C. difficile diarrhea and is indirect evidence for hand carriage as a means of nosocomial C. difficile spread.

Clostridium difficile diarrhea and colonization after treatment with abdominal infection regimens containing clindamycin or metronidazole.

One hundred fifty-six patients with presumed or documented abdominal infections were treated with amikacin/metronidazole/placebo (Group 1, 56 patients), amikacin/clindamycin/placebo (Group 2, 57 patients), or amikacin/clindamycin/ampicillin (Group 3, 43 patients) to determine both the therapeutic efficacy of the various regimens and the type of complications due to Clostridium difficile. C. difficile diarrhea occurred in 15 of 156 patients (9.6%), and C. difficile colonization occurred in 14 of 156 patients (9%) during treatment and 30 days of follow-up. The number of C. difficile diarrhea cases in Group 1 (3 of 56) was significantly lower than in Group 2 (9 of 57, p less than 0.05), but not in Group 3 (3 of 43). Exclusion of all patients who received other antibiotics in the 30-day poststudy period revealed no C. difficile diarrhea or colonization in Group 1 (0 of 13) and an acquisition rate of 31% (14 of 45) with the regimens containing clindamycin (p less than 0.02). Successful treatment outcomes (106 evaluable patients) were not statistically different among the three groups (Group 1, 64%; Group 2, 76%; and Group 3, 88%), but these data were difficult to interpret because, by chance, significantly more patients in Group 1 had bacteremia at entry (p less than 0.01), and patients in Group 3 had significantly more biliary tract infections (p less than 0.02) and significantly more favorable acute physiology scores (p less than 0.05). Use of metronidazole can reduce complications related to C. difficile, particularly if additional antimicrobials other than aminoglycosides are avoided.

Detection of asymptomatic Clostridium difficile carriage by an alcohol shock procedure.

Direct inoculation to cefoxitin-cycloserine-fructose agar and broth was compared with alcohol shock-chopped meat broth inoculation for optimal detection of Clostridium difficile in fecal samples. Alcohol shock is significantly more sensitive than cefoxitin-cycloserine-fructose agar or broth and may be the method of choice to detect C. difficile in asymptomatic carriers.

Nosocomial abscess. Results of an eight-year prospective study of 32,284 operations.

This article details the results of 114 abscesses found after 32,284 operations during a 30-day prospective infection surveillance. Abscesses occurred more often after gastric/esophageal (3.6%), colonic/appendiceal (2.8%), and pancreatic/biliary (1.5%) operations. Abscesses were intra-abdominal (58%), pelvic/perineal (31%), and retroperitoneal (3%). The most common pathogens were Escherichia coli, enterococci, and Bacteroides organisms. Abscess symptoms appeared 10 +/- 6 days (mean +/- SEM) after surgery and were drained 8 +/- 8 days after onset of symptoms. Hospital stay from onset of symptoms to discharge was four times greater than that for wound infection. Twenty-seven patients (28%) died. Mortality was increased in patients older than 50 years and in those with renal failure or multiple abscesses. Nosocomial abscesses had a greater morbidity than would infection. Excessive expense and high mortality warrant infection surveillance for both wound infection and ongoing nosocomial abscesses.

Results of a prospective, 18-month clinical evaluation of culture, cytotoxin testing, and culturette brand (CDT) latex testing in the diagnosis of Clostridium difficile-associated diarrhea.

An 18-mo evaluation of culture, cytotoxin, and latex testing for Clostridium difficile was performed between July 1, 1985, and December 31, 1986, on 1,536 specimens from 1,406 patients during evaluation of diarrhea. All cases with at least one test positive were investigated for clinical status. There were 144 Clostridium difficile-associated diarrhea (CAD) patients; 139 (97%) were positive by culture, 96 (67%) by cytotoxin, and 98 (68%) by latex testing. In the 1,262 non-CAD patients with diarrheal stool, 89 (7.1%) were positive by culture, 18 (1.4%) by cytotoxin, and 68 (5.4%) by the latex test. No CAD patient was positive by cytotoxin testing only, and two were positive by latex testing only. The culture and cytotoxin positivity were similar to our previous reports of 90-97% and 70-73%, respectively. Latex sensitivity (68%) was comparable to that of cytotoxin testing in this large group of patients (p greater than 0.5). Overall, in the 1,262 patients without clinical evidence of Clostridium difficile disease, positive tests by latex testing (5.4%) were intermediate between those of culture (7.1%, p less than 0.1) and cytotoxin (1.4%, p less than 0.001).

Pseudomonas aeruginosa as a primary pathogen in children with bacterial peritonitis.

This prospective study compared the efficacy of sulbactam/ampicillin and clindamycin/gentamicin in the treatment of children with bacterial peritonitis. Of the 29 children enrolled, 17 were evaluable; eight received sulbactam/ampicillin/gentamicin and nine clindamycin/gentamicin. Sixteen patients were previously healthy children with appendicitis. An average of 3.6 bacterial species were recovered from the peritoneal fluid of each patient. E coli and B fragilis were the most common aerobic and anaerobic isolates, recovered from 15 and ten patients, respectively. Pseudomonas aeruginosa was recovered from seven of 17 children; the three children with P aeruginosa infections randomized to the sulbactam/ampicillin group received gentamicin in addition to the investigational agents throughout the treatment course. Although the study groups were small, there was no difference in age, sex, number of pathogens per patient, duration of hospitalization, toxicity, or treatment failures between the two treatment groups or between children infected with P aeruginosa and controls. As a result of the high prevalence of P aeruginosa in the peritoneal exudate of otherwise healthy children with appendicitis, initial antimicrobial therapy in this patient population should include agents effective against this organism.

Pseudomonas infection of the biliary system resulting from use of a contaminated endoscope.

Pseudomonas aeruginosa was present in bile cultures from 10 patients who had undergone previous endoscopic retrograde cholangiopancreatography in 1984. After environmental cultures and review of instrument disinfection, we traced the infections to a single endoscope contaminated with P. aeruginosa, serotype 10. Although the instrument had been cleaned repeatedly with an automatic endoscope cleaning machine, P. aeruginosa survived on residual moisture left in the channels of the endoscope. Contamination ended only after we began to manually suction alcohol through the endoscope before air drying. In 5 of 10 patients, P. aeruginosa caused clinical infections including gangrenous cholecystitis, abscesses, and death. We could identify no factor that distinguished symptomatic from asymptomatic patients. In asymptomatic patients, P. aeruginosa was recovered from gallbladder bile up to 2 mo after endoscopic retrograde cholangiopancreatography. As this P. aeruginosa epidemic was discovered retrospectively because we monitor bile cultures, we advocate this practice as part of endoscopic retrograde cholangiopancreatography procedures.

Preoperative hair removal with clippers does not increase infection rate in clean surgical wounds.

For a one year period, hair was removed from the operative site with clippers rather than by shaving with a razor or by application of depilatories. The study involved comparison of clean (Class I) wound infection rates in 2,580 patients after clipping was instituted compared with 17,424 patients studied in seven preceding years. There was no significant change in the wound infection rate (1 per cent) when compared with the three years immediately preceding. There was no change in the identified distribution of the infecting organism. Failure to show a clear reduction in wound infection rate was probably related to the low historic base line rate. There were definite benefits achieved by avoiding cancellation of elective operations, by using operating room personnel more efficiently and by expediating the surgical schedule.