Kiran Shah

Microbiology of Healthy and Diseased Adenoids

Objective To determine the qualitative and quantitative microbiology of core adenoid tissue obtained from four groups of 15 children each, with recurrent otitis media (ROM), recurrent adenotonsillitis (RAT), obstructive adenoid hypertrophy (OAH), and occlusion or speech abnormalities (controls).

Bacteriology of Adenoids and Tonsils in Children with Recurrent Adenotonsillitis

Adenoids and tonsils electively removed from 25 children with a history of recurrent group A β-hemolytic streptococci (GABHS) adenotonsillitis were cultured for aerobic and anaerobic bacteria. Two hundred twenty-four organisms (112 aerobes and facultatives, 110 anaerobes, and 2 Candida albicans) were isolated from the tonsils, and 229 (111 aerobes and facultatives and 118 anaerobes) were isolated from the adenoids. Mixed infection was present in all instances, with an average of 9.1 isolates per specimen. The predominant aerobes were Streptococcus sp, Haemophilus influenzae, and GABHS, and the prevalent anaerobes were Peptostreptococcus, Prevotella, and Fusobacterium spp. β-Lactamase-producing bacteria were detected in 72 isolates recovered from 22 tonsils (88%) and in 74 isolates recovered from 21 adenoids (84%). Discrepancies in the organisms recovered were found between the tonsils and adenoids. Of the aerobic isolates, 20% were isolated only in tonsils and 18% only in adenoids. Of the anaerobes, 20% were found only in tonsils and 26% only in adenoids. This study demonstrates a polymicrobial aerobic-anaerobic flora in both adenoids and tonsils, and discrepancies in recovery of pathogens such as GABHS. The adenoids may serve as a potential source of tonsillitis caused by GABHS.

Aerobic and anaerobicbacteriologic features of serous otitis media in children

Aspirates of serous ear fluids from 57 children were examined for aerobic and anaerobicbacteria. Bacterial growth was noted in 23 patients (40 per cent). Aerobic organisms only were recovered in 13 aspirates (57 per cent of the culture-positive aspirates); anaerobic bacteria in four (17 per cent); and mixed aerobic and anaerobic bacteria in six (26 per cent). A total of 45 bacterial isolates were recovered, accounting for 2.0 isolates per specimen (1.4 aerobes and 0.6 anaerobe). There were a total of 31 aerobic isolates, including Hemophilus influenzae (eight isolates), Staphylococcus aureus and Streptococcus pneumoniae (five of each), and Staphylococcus epidermidis and alpha-hemolytic streptococcus (four of each). Fourteen anaerobes were recovered, including anaerobic gram-positive cocci and Bacterdides melaninogenicus (five isolates each) and Propionibacterium acnes (three isolates)

Aerobic and anaerobic bacteriology of otorrhea associated with tympanostomy tubes in children.

The microbiology of in 55 ear aspirates obtained from 34 children with chronic otorrhea was studied. Aspiration of the middle ear exudate was done immediately following removal of tympanostomy tube (TT). The middle ear aspirates and swab specimens of the external auditory canals were cultured for aerobic and anaerobic bacteria. Sixty-five isolates were recovered only from the middle ears, 73 only from the external ear canals, and 73 were present at both sites. Analysis of the 138 middle ear isolates demonstrated the recovery of aerobic bacteria only in 28 patients (50%), anaerobes only in seven (13%), and both aerobes and anaerobes in 20 (36%). There were 77 aerobic and 61 anaerobic isolates. Commonly recovered aerobes were Pseudomonas aeruginosa (17 isolates), Staphylococcus aureus (11), Proteus sp. (7), Moraxella catarrhalis (6), Klebsiella pneumoniae (5) and non-typable Haemophilus influenzae (5). Commonly isolated anaerobes were Peptostreptococcus sp. (25 isolates), Prevotella sp. (10), Bacteroides sp. (8) and Fusobacterium sp. (6). Pseudomonas aeruginosa and S. aureus were more often isolated in children older then 6 years. These findings demonstrate the polymicrobial bacteriology of TT-related otorrhea in children. Specimens collected from the external auditory canals can be misleading. Reliable information can be obtained from the ear exudes when collected through the TT or through the open perforation after their removal.

Microbiology of serous otitis media in children: correlation with age and length of effusion.

The purpose of this study was to correlate the microbiology of serous otitis media in children with the duration of the condition and the patients age. Aspirates of serous ear fluids from 114 children were examined for aerobic and anaerobic bacteria. Bacterial growth was noted in 47 patients (41%). Aerobic organisms only were recovered in 27 aspirates (57% of the culture-positive aspirates); anaerobic bacteria only in 7 (15%); and mixed aerobic and anaerobic bacteria in 13 (28%). A total of 83 bacterial isolates were recovered, accounting for 1.8 isolates per specimen (1.2 aerobes and 0.6 anaerobe). There were a total of 57 aerobic isolates, including Haemophilus influenzae (15 isolates), Streptococcus pneumoniae (13), and Staphylococcus sp (12). Twenty-six anaerobes were recovered, including anaerobic gram-positive cocci (10), Prevotella spp (8), and Propionibacterium acnes (4). The rate of positive cultures (20 of 36; 56%) was higher in patients younger than 2 years of age than in those older than 2 years of age (27 of 78; 35%). Streptococcus pneumoniae and H influenzae were more often isolated in children younger than 2 years of age and those with effusion for 3 to 5 months, whereas anaerobes were recovered more often in those older than 2 years of age and those with effusion for 6 to 13 months. These data illustrate the effects of the length of effusion and age on the recovery of aerobic and anaerobic bacteria in serous otitis media.

Effect of amoxicillin or clindamycin on the adenoids bacterial flora

OBJECTIVE We sought to compare the effect on the adenoid bacterial flora of patients with recurrent otitis media of antimicrobial therapy with amoxicillin (Am) or clindamycin (C). Patients and methods Forty-five children scheduled for elective adenoidectomy participated in a prospective randomized study. They were divided into 3 groups of 15 each to receive either no therapy (control) or 10 days of therapy with Am or C. Core adenoid tissues was quantitatively cultured for aerobic and anaerobic bacteria. RESULTS Polymicrobial aerobic-anaerobic flora were present in all instances. The predominant aerobes in all groups were alpha-hemolytic and gamma-hemolytic streptococci, Haemophilus influenzae, Staphylococcus aureus, group A beta-hemolytic streptococci, and Moraxella catarrhalis. The prominent anaerobes were Peptostreptococcus, Prevotella, and Fusobacterium spp. The number of isolates was significantly reduced in those treated with Am (n = 110, P < 0.05) or C (n = 58, P < 0.001) compared with control (n = 148). The number of bacteria per gram/tissue was lower in those treated with either antibiotics. The number of potential pathogens was lower in those treated with C compared with the other 2 groups (P < 0.001). The number of beta-lactamase-producing bacteria was lower in those treated with C than in those treated with Am (P < 0.025) or control (P < 0.001). CONCLUSIONS These data illustrate the ability of C and, to a lesser degree, of Am to reduce the bacterial load as well as potential pathogens and beta-lactamase-producing bacteria from the adenoids of children with recurrent otitis media.

Sinusitis in neurologically impaired children

The microbiologic features of infected sinus aspirates in nine children with neurologic impairment were studied. Anaerobic bacteria, always mixed with aerobic and facultative bacteria, were isolated in 6 (67%) aspirates and aerobic bacteria only in 3 (33%). There were 24 bacterial isolates, 12 aerobic or facultative and 12 anaerobic. The predominant aerobic isolates were Klebsiella pneumoniae, Escherichia coli, and Staphylococcus aureus (2 each) and Proteus mirabilis, Pseudomonas aeruginosa, Haemophilus influenzae, Moraxella catarrhalis, and Streptococcus pneumoniae (1 each). The predominant anaerobes were Prevotella sp. (5), Peptostreptococcus sp. (4), Fusobacterium nucleatum (2), and Bacteroides fragilis (1). β-Lactamase-producing bacteria were isolated from 8 (89%) patients. Organisms similar to those recovered from the sinuses were also isolated from tracheostomy site and gastrostomy wound aspirates in five of seven instances. This study demonstrates the uniqueness of the microbiologic features of sinusitis in neurologically impaired children, in which, in addition to the organisms known to cause infection in children without neurologic impairment, facultative and anaerobic gram-negative organisms that can colonize other body sites are predominant.

Increased antimicrobial resistance in organisms recovered from otitis media with effusion

Previous studies concerning the microbiology of otitis media with effusion (OME) did not correlate the past use of antimicrobial agents with the recovered organisms antimicrobial susceptibility. A retrospective analysis of cultures obtained from aspirates of 129 children with OME was performed. The study identified the isolated organisms and determined their susceptibility to the most recently administered antimicrobials. Bacterial growth was noted in 58 (45 per cent) patients. Aerobic organisms only were recovered in 37 aspirates (63 per cent of the culture-positive aspirates); anaerobic bacteria in seven (12 per cent); and mixed aerobic and anaerobic bacteria in 14 (24 per cent). A total of 92 bacterial isolates were recovered, accounting for 1.6 isolates per specimen (1.1 aerobes and 0.5 anaerobes). There were a total of 66 aerobic isolates, including Haemophilus influenzae non type-b (20 isolates), Streptococcus pneumoniae (17), and Staphylococcus spp. (seven). Twenty-six anaerobes were recovered, including Peptostreptococcus spp. and Prevotella spp. (eight each) and Propionibacterium acnes (four). Resistance to the antimicrobial used was found in 60 (65 per cent) isolates, recovered from 41 (71 per cent) of the patients. Of the 41 patients in whom resistance was detected, 37 (90 per cent) had been treated within three months of culture and four (10 per cent) had completed treatment more than three months before the cultures were taken (p < 0.01). The highest rate of recovery of resistant organisms was following trimethoprim-sulfamethoxazole (96 per cent), amoxycillin (71 per cent), and azithromycin (56 per cent). Of the patients treated with amoxycillin, H influenzae predominated. S pneumoniae was recovered from four of the seven (57 per cent) after trimethoprim-sulfamethoxazole, four of 14 (29 per cent) following amoxycillin, and three of 11 (27 per cent) after azithromycin. The data illustrate the relationship between resistance to the antimicrobials given to children and their recovery from the middle ear of patients with OME.