Showing papers by "Itzhak Brook published in 1997"

Microbiology of Otitis Externa

Abstract: Microbiologic and clinical data from 26 patients with otitis externa were prospectively evaluated. Specimens were processed for aerobic and anaerobic bacteria. Bacterial growth was noted in 23 specimens. A total of 33 aerobic and 2 anaerobic bacteria were recovered. Aerobic bacteria only were isolated in 21 (91%) patients, anaerobic bacteria only in 1 (4%), and mixed aerobic and anaerobic bacteria in 1 (4%). The most common isolates were Pseudomonas aeruginosa (14 instances), Staphylococcus aureus (7), Acinetobacter calcoaceticus (2), Proteus mirabilis (2), Enterococcus faecalis (2), Bacteroides fragilis (1), and Peptostreptococcus magnus (1). One isolate was recovered in 13 (57%) patients, 2 isolates in 8 (35%), and 3 isolates in 2 (9%). These data illustrate the polymicrobial nature of otitis externa in about half of the patients and the role of anaerobic bacteria in 8% of them. Further studies are warranted to evaluate the therapeutic implications of these findings.

Microbiology of chronic maxillary sinusitis: comparison between specimens obtained by sinus endoscopy and by surgical drainage.

Abstract: The aerobic and anaerobic microbiology of sinus aspirates obtained during surgery was compared with culture of samples obtained by endoscopy. Six patients with chronic maxillary sinusitis were evaluated. Polymicrobial flora was found in all specimens (twoto-five isolates/sample). A total of 24 isolates (18 anaerobic, five aerobic and one microaerophilic) was obtained from sinus aspirates, and 25 isolates (16 anaerobic and nine aerobic) were found in endoscopic specimens. The predominant organisms were Prevotella spp., Fusobacterium nucleatum, Peptostreptococcus spp. and Staphylococcus spp. Concordance in the type and concentration of organisms was found in all cases. Sixteen of the 18 anaerobes isolated from sinus aspirates were also found in the concomitant endoscopic sample. Five aerobic isolates were found in both sinus aspirates and endoscopic samples and their concentration was similar. However, four aerobic gram-positive bacteria (< lo4 cfu/sarnple) were found only in endoscopy samples. This pilot study demonstrates the usefulness of endoscopic aspiration in the isolation of bacteria from chronically infected maxillary sinuses.

Bacterial colonization of pacifiers of infants with acute otitis media

Abstract: The presence of aerobic and facultative anaerobic bacteria on the surface of pacifiers used by children with acute otitis media was investigated. The surface of 40 recently used pacifiers was swabbed after they were allowed to dry for five to six minutes. The swabs were processed quantitatively for the presence of aerobic bacteria. The antibacterial activity of the pacifier material was tested in vitro. Microorganisms were isolated from 21 (52.5 per cent) pacifiers. The number of colonies per pacifier varied between one and 35 (average six). The isolates included eight alpha-haemolytic streptococci, six Staphylococcus epidermis, five Candida albicans, five alpha-haemolytic streptococci, three Neisseria spp. and two Staphylococcus aureus. The pacifier material was shown to be inhibitory against S. aureus. This study illustrated that pacifiers do not contain high numbers of organisms and therefore are not likely to serve as a source of persistence of transfer of organisms.

Immune response to Fusobacterium nucleatum, Prevotella intermedia and other anaerobes in children with acute tonsillitis.

Abstract: The number of aerobic and anaerobic bacteria was determined in the saliva of 20 children with acute group A -haemolytic streptococcal (GABHS) pharyngo-tonsillitis, and 20 with acute non-GABHS tonsillitis. Antibody titres to four Gram-negative anaerobic bacilli that reside in the oropharynx (Fusobacterium nucleatum, Prevotella intermedia, Porphyromonas gingivalis, and Actinobacillus actinomycetemcomitans) were determined in these and 20 control patients. An average of 8.8 aerobic and anaerobic isolates per patient saliva specimens were found during the acute tonsillitis stage in both groups, and 6.9 (in GABHS tonsillitis) and 5.6 (in non-GABHS tonsillitis) 5‐6 weeks later. There were 10- to 1000-fold more bacteria in the acute stages of the inflammation in both GABHS and non-GABHS groups. These bacteria were Staphylococcus aureus, Haemophilus influenzae, Moraxella catarrhalis, Peptostreptococcus spp., F. nucleatum, Prevotella spp. and Porphyromonas spp. Significantly higher antibodies levels to F. nucleatum and P. intermedia were found in the second serum sample of patients with non-GABHS pharyngo-tonsillitis (P < 0.001) and GABHS tonsillitis (P < 0.05), as compared with their first sample or the levels of antibodies in controls. The increase in the number of several aerobic and anaerobic bacteria during acute tonsillitis and the increase in antibody levels to F. nucleatum and P. intermedia , known oral pathogens, may suggest a possible pathogenic role for these organisms in acute nonGABHS and GABHS tonsillitis.

Microbiology of nonbullous impetigo

Abstract: Our objective was to establish the aerobic and anaerobic microbiology of nonbullous impetigo (NI) in children. We used a retrospective review of clinical microbiology laboratory and patients' records. Specimens were obtained from 40 patients with NI lesions and showed bacterial growth. Aerobic or facultative anaerobic bacteria only were present in 24 patients (60%), strict anaerobic bacteria only in 5 patients (12.5%), and mixed anaerobic-aerobic flora was present in 11 patients (27.5%). Sixty-four isolates were recovered (1.6 per specimen): 43 aerobic or facultative, and 21 anaerobic. The predominant aerobic and facultative bacteria were Staphylococcus aureus (29 isolates), Group A beta hemolytic streptococcus (GABHS) (13 isolates), and Escherichia coli (1 isolate). The predominant anaerobes were Peptostreptococcus spp. (12), pigmented Prevotella spp. (5), Fusobacterium spp. (2), and Bacteroides fragilis (1). Single bacterial isolates were recovered in 17 patients (42.5%), 13 of which were S. aureus. S. aureus alone or mixed with GABHS or Peptostreptococcus spp. were isolated from all body sites. Mixed flora of Peptostreptococcus spp. with Prevotella spp. or Fusobacterium spp. was mostly found in infections of the head and neck, while E. coli mixed with B. fragilis and Peptostreptococcus spp. were isolated from one infection of the buttocks area. Thirty-three organisms isolated from 32 patients (80%) produced the enzyme beta-lactamase. This study demonstrates the polymicrobial aerobic-anaerobic microbiology of NI lesions.

Effect of penicillin or cefprozil therapy on tonsillar flora.

Abstract: The effect on the tonsillar bacterial flora of antimicrobial therapy with penicillin or a second-generation cephalosporin (cefprozil) was studied. Sixty children scheduled for elective tonsillectomy because of recurrent group A beta-haemolytic streptococcal tonsillitis participated in a prospective randomized study that divided them into three groups. One group received no therapy, and the others were given either penicillin or cefprozil for 10 days prior to surgery. The core of the patients' tonsils was cultured for aerobic bacteria. Group A beta-haemolytic streptococci (GABHS) were isolated from 15/20 (75%) of untreated, 11/20 (55%) of penicillin, and 2/20 (10%) of the cefprozil group (P < 0.001). Thirty-two beta-lactamase-producing bacteria were recovered from 19/20 (95%) of untreated, 33 from 17/20 (85%) treated with penicillin and six from 4/20 (20%) treated with cefprozil (P < 0.01). Alpha-haemolytic streptococci (AHS) inhibiting GABHS were less often isolated from patients treated with penicillin. These data illustrate the ability of a second-generation cephalosporin to eradicate GABHs, as well as beta-lactamase-producing bacteria, while preserving AHS.

Bacterial Flora of Stethoscopes' Earpieces and Otitis Externa:

Abstract: External otitis caused by Staphylococcus aureus was observed in a nurse after extensive use of a stethoscope. The infection recurred and a similar organism was isolated from the stethoscope's earpiece. The infection did not recur after the earpiece was cleansed after each use. In a prospective study, the bacterial flora of 35 earpieces was evaluated. Fifty-three isolates, 36 aerobic or facultative and 17 anaerobic, were recovered. The number of organisms per earpiece ranged from 14 to 204 (average 92 ± 17). The predominant isolates were Staphylococcus epidermidis (16 isolates), Propionibacterium acnes (12), and S aureus (7). The study demonstrates the colonization of the stethoscope's earpiece with microorganisms that possess the potential for causing nosocomial infection.

Uvulitis caused by anaerobic bacteria.

Abstract: Objective I present two children with bacteremic uvulitis due to anaerobic bacteria. Results Fusobacterium nucleatum was recovered from the blood, and Haemophilus influenzae type b was recovered from a surface uvular culture of one patient. beta-Lactamase-producing Prevotella intermedia was isolated for the blood of the other patient. Both patients responded to parenteral, followed by oral, antimicrobial therapy. Conclusions These findings illustrate the need to send blood cultures for both aerobic and anaerobic bacteria in patients with uvulitis.

The Stethoscope As a Potential Source of Transmission of Bacteria

Abstract: To the Editor: Dr. Itzhak Brook's letter (1997;19:608) is of importance not only in showing that the stethoscope may be a vector for both aerobic and anaerobic bacteria but also in demonstrating that the stethoscope may be contaminated when used in physical examinations. The various textbook recommendations for cleaning before and after use are known commonly.1-3 However, these are not always adhered to, nor are adequate to prevent contamination of patients.4 Furthermore, hygiene rituals for stethoscopes often ignore the need for meticulous cleaning. The risk of contamination is high, especially in clinical settings and particularly for patients in the intensivecare unit or neonatal intensive-care unit.' In those very high-risk settings, the use of individual stethoscopes for each patient is known to be the most effective prevention. (Unfortunately, this makes doctors now a target of potential cross-infections via earpieces). To minimize this hazard, using single-use stethoscope-covers (Figure) would assure a high hygiene standard. Such covers could be used before physical examination and could be disposed of easily thereafter. We were able to detect 13 different patented devices designed to decrease stethoscope contamination, but only two seem to be feasible for real practice (Wurzburger, US Patent #5,538,004, 1996; Rothan-Tondeur, PCT #W0 96/38088, 1996). These devices involve a disposable cover that is attached to the diaphragm of the stethoscope prior to examination of the patient. After obtaining the desired clinical information, the cover can be removed easily. Application and disposal of these devices take 3 to 5 seconds. Because disposable stethoscopes are unrealistic, we believe these covers are a good alternative to disinfection procedures; but, as long as such covers are not available, meticulous disinfection of stethoscopes prior to use should be carried out.