Bacteremia associated with lower gastrointestinal endoscopy: Fact or fiction?

In an effort to elucidate whether bacteremia occurs during endoscopic examination of the lower gastrointestinal tract, two prospective spective studies were undertaken involving patients undergoing colonoscopy and proctosigmoidoscopy. The former group has been presented earlier, and the second study, which includes the proctosigmoidoscopy group, is the basis for this study. Fiftyseven patients undergoing proctosigmoidoscopy were studied. Excluded from the study were patients with fever, diarrhea, inflammatory bowel disease, valvular heart disease, vascular prosthesis, chemotherapy, and immunosuppression. Aerobic and anaerobic blood cultures were taken before, during, and after proctosigmoidoscopy. Additional cultures were taken after a biopsy or polypectomy. Skin cultures were taken from the venipuncture site prior to venipuncture. No bacteremia was demonstrated. Three blood cultures were positive, but all were considered contaminants on the basis of the nature of organisms. No correlates could be drawn as to the depth of insertion, length of time, or position of patient during the procedure. It is concluded that no significant bacteremia occurs during proctosigmoidoscopy. Further studies are warranted in the excluded high-risk group.     

Does bacteremia follow colonoscopy?

In order to determine the risk of bacteremia from colonoscopy, we cultured blood specimens from 40 patients the day before laxative and enema preparation; right after such preparation; and 15 min, 1 hr, and 4 hr after colonscopy. Bacteremia was not induced by either the vigorous preparation or the colonscopy which, in 27 patients, included polypectomy, biopsy, and/or fulgurations. On the basis of our data, we conclude that the risk of bacteremia following colonoscopy is small, and we doubt the need of antibiotic prophylaxis for those with susceptible hearts.     

Continuous high-grade mycobacterium avium-intracellulare bacteremia in patients with the acquired immune deficiency syndrome

Serial quantitative blood cultures were performed before and during treatment in four patients with the acquired immune deficiency syndrome (AIDS) and Mycobacterium avium-intracellulare bacteremia. Initial colony counts were 350 to 28,000 cfu/ml, the counts declined substantially with treatment in two patients, and they declined modestly with treatment but rose when it was stopped in the other two. In one patient who was studied in detail, most of the circulating organisms were within the leukocytes, colony counts in blood subjected to lytic agents were 1.9- to 5.2-fold higher than in unlysed blood, and there were 10(5) to 10(6) times more organisms per gram in several tissue specimens obtained at autopsy than per milliliter of blood. It is concluded that continuous high-grade bacteremia is common in patients with AIDS and severe M. avium-intracellulare infections and that serial quantitative blood cultures provide a potential means for studying treatment in these patients.     

Yersinia pestis infection in Vietnam. II. Quantiative blood cultures and detection of endotoxin in the cerebrospinal fluid of patients with meningitis.

Quantitative blood cultures were obtained from 42 patients with acute Yersinia pestis infection to determine whether the concentration of bacteria in blood influenced the clinical severity and outcome of illness. In 17 bacteremic patients, colony counts in blood cultures ranged from less than 10 to 4 X 10(7)/ml. Three of five patients with colony counts of greater than 10(2)/ml died, and two patients survived episodes of hypotension. Results from plasma limulus tests were positive at the time of admission in three of 10 patients tested, and these three patients had bacteremia with colony counts of greater than 10(2)/ml. Meningitis developed in three patients and pneumonia in two patients; these five patients a-l had buboes in the axillary region. Endotoxin was detected with the limulus test in the cerebrospinal fluid in the three patients with meningitis. Ten patients randomly assigned to receive streptomycin or trimethoprim-sulfamethoxazole survived. Those treated with streptomycin had a shorter median duration of fever and a lower incidence of complications than did the patients treated with trimethoprim-sulfamethoxazole.     

Infectious complications of endoscopic procedures in bone marrow transplant recipients

The prevalence of clinically relevant bacteremia after endoscopic procedures in bone marrow transplant recipients was assessed retrospectively. Bacteremia, within 24 hr of procedure, was defined as positive blood cultures, while hypotension and temperature greater than 38° C were taken as possible indicators of bacteremia. Sixty-seven procedures were performed in 53 endoscopic sessions (upper endoscopy 37, flexible sigmoidoscopy 7, upper endoscopy + flexible sigmoidoscopy 8, colonoscopy 1). Twenty-five endoscopic sessions were performed in patients receiving broad-spectrum antibiotics and 28 sessions in patients not receiving antibiotics. Both groups were comparable with respect to patient characteristics, procedures performed, and immune status. No patient in either group developed hypotension. One patient developed fever after flexible sigmoidoscopy; no source of fever was identified. We conclude that: (1) there were no episodes of clinically relevant bacteremia attributable to endoscopic procedures, and (2) not all bone marrow transplant recipients require routine antibiotic prophylaxis prior to endoscopic procedures.     

Bacteremia associated with lower gastrointestinal endoscopy,fact or fiction?

A survey of the medical literature reveals conflicting data as to whether bacteremia occurs during endoscopic examination of the lower gastrointestinal tract. In an attempt to study this problem a prospective study was undertaken, and the first arm of the study included patients undergoing colonoscopy. The second arm of the study, comprising patients undergoing proctosigmoidoscopy, will be presented subsequently. Fifty-one patients undergoing colonoscopy were studied. Excluded from the study were patients with elevation of temperature above 101°F, inflammatory bowel disease, diarrhea, valvular heart disease, vascular prosthesis, chemotherapy, or immunosuppression. Aerobic and anaerobic cultures were done before and after the procedure, as well as at timed intervals during the procedure. Whenever biopsy or polypectomy were carried out, further cultures were done. Skin cultures were done from venipuncture sites. In one patient (2 per cent)Staphylococcus epidermidis was found in more than one set of cultures. Polypectomy or biopsy were not associated with bacteremia. Read at the meeting of the American Society of Colon and Rectal Surgeons, Hollywwod, Florida, May 11 to 16, 1980.     

Bacteremia caused by digestive system endoscopy.

AIM: to evaluate bacteremias caused during endoscopic examination of the digestive tract. PATIENTS AND METHODS: prospective study of randomly selected patients who underwent digestive system endoscopic examination. Emergency endoscopic examinations were excluded. RESULTS: a total of 102 patients were analyzed. Of 44 patients who underwent gastroscopy, 11 (25%) subsequently had positive blood culture, and Staphylococcus spp and Streptococcus spp were isolated. Of 30 patients who underwent colonoscopy, 3 (10%) had positive blood cultures, and Staphylococcus spp were isolated. Of 28 patients who underwent endoscopic retrograde cholangiopancreatography, 11 (39.2%) had positive blood cultures, and Escherichia coli, Morganella morganii, Staphylococcus spp and Streptococcus spp were isolated. No deaths, endocarditis or other septic phenomena were attributed to bacteremia. CONCLUSIONS: the incidence of bacteremia ranged from 10% to 39% depending on the type of endoscopy. The microorganisms that were isolated most frequently were Staphylococcus spp and Streptococcus spp. Gram-negative bacilli and enterobacteria were isolated in patients who had undergone endoscopic retrograde cholangiopancreatography.     

Prospective evaluation of the risk of bacteremia associated with transesophageal echocardiography

BACKGROUND. Transient bacteremia may lead to endocarditis in patients with significant valvular lesions. METHODS AND RESULTS. Because transesophageal echocardiography selects a patient population with a high prevalence of valvular lesions, we prospectively evaluated the risk of transient bacteremia associated with transesophageal echocardiography in 49 patients. Blood cultures were obtained immediately before transesophageal echocardiography and at 5, 10, and 20 minutes after the start of the procedure. For each culture, 30 ml venous blood was obtained and 10 ml was inoculated into each of an Isolator tube, Septi-chek bottle, and a nonvented Trypticase soy broth bottle. Broth cultures were incubated for 14 days. Blood from the Isolator tube was plated onto appropriate media for recovery of bacteria and fungi. Two patients were excluded from analysis because the final two sets of blood cultures could not be obtained. Among the remaining 47 study patients, two preprocedure control blood cultures were positive, and two of 141 subsequent cultures were positive. All isolates were considered contaminants. Thus, we found no significant bacteremia due to pathogenic oral flora during transesophageal echocardiography (0%; 95% CI, 0.0-7.5%). CONCLUSIONS. Although recommendations for antimicrobial prophylaxis for transesophageal echocardiography should be individualized for each patient, many patients may not require antimicrobial prophylaxis.     

The Absence of Bacteremia During Colonoscopy

Seventy-nine blood cultures were obtained from 15 patients undergoing diagnostic colonoscopy. Aerobic and anaerobic culture technics showed no evidence of bacteremia during or after the procedure. The colonoscope was passed to the cecum in 12 of the 15 patients. The time of the procedure varied from 15–60 minutes with an average of 30 minutes. The results of this study supplies further evidence that bacteremia during colonoscopy is an infrequent occurrence.     

Successful short-term suppression of clarithromycin-resistant Mycobacterium avium complex bacteremia in AIDS. California Collaborative Treatment Group.

During a randomized study of clarithromycin plus clofazimine with or without ethambutol in patients with AIDS and Mycobacterium avium complex (MAC) bacteremia, eight participants received additional antimycobacterial drugs following the detection of a clarithromycin-resistant isolate (MIC, > 8 micrograms/mL). A macrolide (seven received clarithromycin, one azithromycin) and clofazimine were continued; additional treatment included various combinations of ethambutol, ciprofloxacin, amikacin, and rifabutin. After the detection of a resistant isolate and before receipt of additional antimycobacterials, the median peak MAC colony count in blood was 105 cfu/mL (range, 8-81,500 cfu/mL). After additional antimycobacterials, the median nadir MAC colony count was 5 cfu/mL (range, 0-110 cfu/mL). Five (63%) of eight patients had a > or = 1 log10 decrease, including two who achieved negative blood cultures; all of these responses occurred in patients originally assigned to clarithromycin plus clofazimine. Treatment of clarithromycin-resistant MAC bacteremia that emerges during clarithromycin-based treatment can decrease levels of bacteremia and transiently sterilize blood cultures.     

Incidence of bacteremia in transesophageal echocardiography: a prospective study of 140 consecutive patients

The incidence of bacteremia related to transesophageal echocardiography was studied in 140 consecutive patients (71 women and 69 men with a mean age of 53.7 +/- 15 years). Thirty-four patients had one or more prosthetic heart valves. Blood cultures were obtained from each patient through separate venipuncture sites immediately before and after transesophageal echocardiography. An additional late blood culture was obtained in 114 patients 1 h later. The skin was cleaned with povidone-iodine and venipunctures were performed with separate butterfly needles with use of sterile gloves and drapes. Blood samples were drawn into separate syringes, transferred to aerobic and anaerobic culture bottles and processed with use of a semiautomated system. The overall incidence of blood cultures positive for bacteremia was 2% (8 of 394 bottles) and all positive cultures grew in a single blood culture bottle. Positive cultures occurred in 4 (1.4%) of 280 bottles before the procedure, in 2 (0.7%) of 280 bottles immediately after the procedure and in 2 (0.9%) of 228 late (1-h) blood culture bottles. Bacterial isolates were coagulase-negative staphylococci (n = 5), Propionibacterium (n = 2) and Moraxella (n = 1). All were considered contaminants. Mean endoscopic time in these patients was not significantly different from that in the other patients. Follow-up of patients with a blood culture positive for bacteremia revealed no clinical evidence of systemic infection. It is concluded that 1) the incidence of bacteremia related to transesophageal echocardiography is very low, and 2) the incidence of blood cultures positive for bacteremia after transesophageal echocardiography is indistinguishable from the anticipated contamination rate.     

Bacteremia associated with percutaneous transluminal coronary angioplasty

Bacteremia after diagnostic cardiac catheterization is uncommon, but bacteremia after percutaneous transluminal coronary angioplasty (PTCA) has not been studied prospectively. Unlike diagnostic cardiac catheterization, PTCA involves the use of an indwelling arterial sheath after completion of the procedure, which is connected to a pressurized heparin solution, both of which increase the risk of local infection and/or bacteremia. During a 16-week period, we prospectively evaluated patients undergoing 164 PTCA procedures in order to determine the frequency of bacteremia and the significance of fever in this patient population. Blood cultures were obtained from the femoral catheter at the conclusion of the procedure and again 30 min later from the indwelling arterial sheath. Temperature was recorded every 30 min for 2 h following PTCA, then every 4 h over the subsequent 36-hr period. Bacterial isolates were recovered from 23/286 blood cultures (8.0%), with Staphylococcus epidermidis the most common organism present (74%). Only one isolate of Staphylococcus aureus was considered to represent true bacteremia and corresponded with the only documented infectious complication. Fever, defined as ?101°F developed in four (2.4%) patients but was procedure related in only one case. The use of the ipsilateral femoral artery for repeat procedures was not associated with either positive blood cultures or difference in maximum temperature elevation. We conclude the overall risk of bacteremia after PTCA is low; therefore, antimicrobial prophylaxis is not warranted. © 1995 Wiley-Liss, Inc.     

Bacteremia Incidence in Pediatric Patients under Dental General Anesthesia

Background. The aim of this study was to assess the incidence of bacteremia from various procedures in children undergoing dental treatment under general anesthesia. Methods. Three blood samples for cultures were obtained from each patient; the first sample (10 ml basal) at the onset of the process and the second sample (10 ml) within 30 seconds following the nasotracheal intubation. The third blood sample (10 ml) was taken 30 seconds after the extraction of a deciduous tooth or a permanent tooth or slow drilling. Following incubation in an automated blood culture system, bacteria were identified by using conventional biochemical methods and commercial identification systems. Chi‐square test was used to assess the findings statistically. Results. All blood cultures were negative before intubation (baseline) in every patient. However, the percentage of positive samples in deciduous tooth extraction and permanent tooth extraction groups were 18/26 (69.2%) and 18/25 (72%), respectively. These values were significantly greater than the results of baseline 0/74 (0%), slow drilling 3/23 (13%), and nasotracheal intubation 9/74 (12.3%) (P < .05). Conclusion. Consequently, the patients treated under dental general anesthesia have to be evaluated with detailed physical examination and antibiotic prophylaxis should be given if required in order to prevent further unexpected bacterial endocarditis.     

Incidence of Bacteremia Following Bronchoscopy with Argon Plasma Coagulation: A Prospective Study

Background

This evaluation was undertaken to determine the incidence of bacteremia and infectious complications associated with argon plasma coagulation (APC) procedures.

Methods

Consecutive patients undergoing bronchoscopy with APC for treatment of endobronchial lesions were studied. Venesection was performed for blood cultures within 60 s of the APC procedure. APC catheter washings were cultured. Patients with positive blood cultures were reviewed immediately. All patients underwent clinical review 1 and 12 weeks after APC.

Results

Forty-two patients underwent 44 APC procedures. Their mean age was 66 ± 12 years. One case (2.3 %) had bacteremia with Acinetobacter lwolfii. APC catheter washing culture was positive in 14 (31.8 %) procedures. No patient had clinical features suggesting infection and there were no complications. Phone review after 1 week revealed no complications. After 3 months, 8 (18 %) had died, all related to advanced lung malignancy and not to the APC procedure.

Conclusions

APC does not appear to increase the risk of bacteremia compared to airway insertion of the bronchoscope. Although contamination of the APC catheter with oropharyngeal commensal bacteria is common, clinically significant infection following the APC procedure is rare.     

LOW‐FREQUENCY OF BACTEREMIA AFTER ENDOSCOPIC SUBMUCOSAL DISSECTION OF THE STOMACH

Background: Mainstream therapy for early gastric cancer in Japan has now shifted from endoscopic mucosal resection (EMR) to endoscopic submucosal dissection (ESD). Although bacteremia is reported as being infrequent and transient in gastric EMR, there are no reports of it being investigated in gastric ESD. This study aimed to determine the frequency of bacteremia in gastric ESD. Patients and Methods: A prospective study, in 46 consecutive patients who underwent gastric ESD, investigated the frequency of bacteremia before and after the procedure. Results: The median time for the total ESD procedure was 105 min (range 30–400). The median volume of the submucosal injection was 80 ml (range 20–260). The mean size of the resected specimen was 40 ± 9.7 mm. Blood cultures obtained before ESD were positive in 4.4% (2/45) of cases. Bacillus subtilis and Bacillus spp. were the isolated microorganisms. Blood cultures obtained 10 min after ESD were positive in 4.3% (2/46) of cases; with the same microorganisms being isolated. Blood cultures obtained 3 h after ESD were all negative. No signs of sepsis were seen in the two patients with a positive blood culture 10 min after ESD. Conclusions: The frequency of bacteremia after gastric ESD was low and transient. ESD for gastric lesions is thought to have a low risk of infectious complications; therefore, prophylactic administration of antibiotics may not be warranted.     

Prospective evaluation of the risk of bacteremia induced by transesophageal echocardiography

BACKGROUND: The incidence of bacteremia induced by transesophageal echocardiography is controversial in the Indian population. This study aimed to find out the occurrence of bacteremia following transesophageal echocardiography. METHODS AND RESULTS: Between February 2000 and January 2001, 47 patients (26 males and 21 females) were enrolled for the study. Their ages ranged from 13 to 61 years (mean: 35 +/- 11.4 years). Patients with prosthetic valves, suspected infective endocarditis and those on antibiotics were excluded. For each procedure, two sets of blood cultures were obtained immediately before and after the procedure. For each blood culture, 10 ml of blood was evenly inoculated into brain-heart infusion broth and biphasic infusion medium and incubated for 7 days. Transesophageal echocardiography was carried out under oropharyngeal anesthesia (xylocaine gel and spray). Two blood cultures taken before the procedure were positive and excluded from the final analysis. Of the remaining 45 patients whose preprocedure blood cultures were sterile, 6 samples (13.3%) were positive after the procedure diphtheroids in 3, micrococci in 2 and aerobic spore formers in 1. CONCLUSIONS: This study demonstrates that the incidence of bacteremia related to transesophageal echocardiography is not insignificant, as reported in previous studies. Though routine antibiotic prophylaxis before transesophageal echocardiography is not advocated, it should be recommended in high-risk patients such as those with prosthetic valves, multivalvular involvement or those with a past history of infective endocarditis.     

Infectious complications of endoscopic injection sclerotherapy

We prospectively assessed the infectious complications of esophageal injection sclerotherapy (EIS) in 38 patients who underwent 104 procedures. Blood cultures were taken prior to and five and ten minutes after injection of the sclerosing agent in all procedures in an attempt to determine the frequency of positive blood cultures. Surveillance cultures were obtained from each patient's pharynx and from the biopsy channel of the endoscope to identify potential sources of bacteremia. The rate of blood culture positivity before injection was not significantly different from that after injection (1.9% vs 4.3%). In only one procedure was the same organism isolated five and ten minutes after sclerotherapy. The isolate in both samples was a Corynebacterium species. Endoscope surveillance cultures were positive prior to 42 of 102 procedures, although none of those organisms subsequently were isolated in the blood cultures. Since the rate of positive blood cultures following EIS is no greater than that before the procedure, the use of prophylactic antibiotics is unnecessary.     

Point-of-care, peer-comparator colonoscopy practice audit: The Canadian Association of Gastroenterology Quality Program--Endoscopy

BACKGROUND

Point-of-care practice audits allow documentation of procedural outcomes to support quality improvement in endoscopic practice.

OBJECTIVE

To evaluate a colonoscopists’ practice audit tool that provides point-of-care data collection and peer-comparator feedback.

METHODS

A prospective, observational colonoscopy practice audit was conducted in academic and community endoscopy units for unselected patients undergoing colonoscopy. Anonymized colonoscopist, patient and practice data were collected using touchscreen smart-phones with automated data upload for data analysis and review by participants. The main outcome measures were the following colonoscopy quality indicators: colonoscope insertion and withdrawal times, bowel preparation quality, sedation, immediate complications and polypectomy, and biopsy rates.

RESULTS

Over a span of 16 months, 62 endoscopists reported on 1279 colonoscopy procedures. The mean cecal intubation rate was 94.9% (10th centile 84.2%). The mean withdrawal time was 8.8 min and, for nonpolypectomy colonoscopies, 41.9% of colonoscopists reported a mean withdrawal time of less than 6 min. Polypectomy was performed in 37% of colonoscopies. Independent predictors of polypectomy included the following: endoscopy unit type, patient age, interval since previous colonoscopy, bowel preparation quality, stable inflammatory bowel disease, previous colon polyps and withdrawal time. Withdrawal times of less than 6 min were associated with lower polyp removal rates (mean difference −11.3% [95% CI −2.8% to −19.9%]; P=0.01).

DISCUSSION

Cecal intubation rates exceeded 90% and polypectomy rates exceeded 30%, but withdrawal times were frequently shorter than recommended. There are marked practice variations consistent with previous observations.

CONCLUSION

Real-time, point-of-care practice audits with prompt, confidential access to outcome data provide a basis for targeted educational programs to improve quality in colonoscopy practice.     

Postpolypectomy lower gastrointestinal bleeding: potential role of aspirin

INTRODUCTION: Limited data exist on the role of aspirin in increasing the risk of clinically significant postpolypectomy bleeding (PPB), which is defined as lower gastrointestinal (GI) hemorrhage following colonoscopic polyp removal requiring transfusion, hospitalization, endoscopic intervention, angiography, or surgery. OBJECTIVES: To determine if aspirin use prior to colonoscopy increases the risk of clinically significant PPB. METHODS: A case-control study of patients with clinically significant PPB at Mayo Clinic Scottsdale and Rochester was performed. Information collected included age, gender, recent use of aspirin or NSAIDs (within three days of colonoscopy), polyp characteristics, and polypectomy technique. The control group consisted of patients matched for age (+/-3 yr), gender, and cardiovascular morbidity who had undergone polypectomy without any complications. The populations were compared to determine the odds ratio (OR) of PPB with aspirin use. RESULTS: During the study period, 20,636 patients underwent colonoscopy with polypectomy at the two institutions and 101 patients presented with clinically significant PPB. Twenty patients were excluded from analysis because of prior anticoagulant use. The remaining 81 patients were matched to 81 patients who had undergone colonoscopy without complications. The two groups were comparable in terms of polyp size (97%< or = 10 mm, bleeding group; 95%< or = 10 mm, control group). Aspirin use prior to polypectomy was 40% in the bleeding group and 33% in the control group (OR 1.41; 95% C.I. 0.68 to 3.04). CONCLUSION: Postpolypectomy bleeding is an uncommon but important complication of endoscopic polypectomy. There was no statistically relevant difference in prior aspirin use before polypectomy in the bleeding group and the matched controls.     

Prospective study of blood culture during transesophageal echocardiography.

To ascertain the incidence and significance of bacteremia associated with transesophageal echocardiography (TEE), 132 consecutive patients (aged 17 to 73 years) free of apparent infection who were undergoing 135 transesophageal echocardiographic procedures from October 1990 to August 1991, were prospectively studied. For each procedure, two sets of blood cultures were obtained for culture 30 to 60 minutes before TEE, immediately after, and 180 to 240 minutes after the procedure. For each blood culture, 10 ml of venous blood was evenly inoculated into aerobic and anaerobic culture bottles and inoculated for 7 days using a radiometric system. A throat swab was obtained immediately before each procedure. Three of 270 preprocedure blood cultures were positive for Bacillus cereus, Staphylococcus simulans, and Peptostreptococcus species, respectively. No blood culture was positive in the immediate postprocedure period. Two of 270 late blood samples grew Staphylococcus epidermidis in the same patient. Nevertheless, the microorganisms isolated from blood cultures were different from those isolated from the throat swab. No patients had fever or evidence of infective endocarditis after TEE during the follow-up period. It is concluded that the incidence of TEE-related bacteremia is extremely low, and a general recommendation for antibiotic prophylaxis during TEE is not warranted.