[Evaluation of the reincubation of positive blood cultures for detection in the BACT-ALERT system for the detection of polymicrobial bacteremia]. / Evaluación de la reincubación de hemocultivos positivos por el sistema BACT-ALERT para la detección de bacteriemias polimicrobianas.

Between February and September 1997, 6588 blood cultures at the Instituto de Cardiología y Cirugía Cardiovascular and Hospital de Niños Ricardo Gutiérrez were studied by using the Bact-Alert system (Organon Teknika) 341 contaminants and 294 episodes of bacteremia (600 samples) were analyzed. From these samples, 280 (95.3%) were monomicrobial episodes and 14 (4.7%) polymicrobial episodes. Positive blood cultures detected by the Bact-Alert system were processed and then reincubated during 7 days, when they were Gram stained and subcultured in blood agar, chocolate agar (both in 5-10% CO2), laked blood agar supplemented with hemin and vitamin K in anaerobic atmosphere (only anaerobic bottles) and CLDE (aerobic conditions). Following reincubation, 3 out of 14 polymicrobial bacteremias were detected, rising the level of detection from 3.7% to 4.7%. Taking into account the total number of bacteremias, only in 3 out of 294 (1%), a second microorganism was detected. Otherwise, in blood cultures where a contaminating microorganism was initially isolated, no further isolates representing a true bacteremia were recovered. Reincubation and terminal subculture of initially positive blood cultures did not provide relevant data in order to change therapeutic measures in the studied population. Due to the increase in costs and labor we consider that this methodology is not routinely advised.

Evaluación de la reincubación de hemocultivos positivos por el sistema BACT-ALERT para la detección de bacteriemias polimicrobianas / Evaluation of the reincubation of positive blood cultures for detection in the BACT-ALERT system for the detection of polymicrobial bacteremia

Between February and September 1997, 6588 blood cultures at the Instituto de CardiologÝa y CirugÝa Cardiovascular and Hospital de Niños Ricardo GutiÚrrez were studied by using the Bact-Alert system (Organon Teknika) 341 contaminants and 294 episodes of bacteremia (600 samples) were analyzed. From these samples, 280 (95.3) were monomicrobial episodes and 14 (4.7) polymicrobial episodes. Positive blood cultures detected by the Bact-Alert system were processed and then reincubated during 7 days, when they were Gram stained and subcultured in blood agar, chocolate agar (both in 5-10 CO2), laked blood agar supplemented with hemin and vitamin K in anaerobic atmosphere (only anaerobic bottles) and CLDE (aerobic conditions). Following reincubation, 3 out of 14 polymicrobial bacteremias were detected, rising the level of detection from 3.7 to 4.7. Taking into account the total number of bacteremias, only in 3 out of 294 (1), a second microorganism was detected. Otherwise, in blood cultures where a contaminating microorganism was initially isolated, no further isolates representing a true bacteremia were recovered. Reincubation and terminal subculture of initially positive blood cultures did not provide relevant data in order to change therapeutic measures in the studied population. Due to the increase in costs and labor we consider that this methodology is not routinely advised.

Evaluación de la reincubación de hemocultivos positivos por el sistema BACT-ALERT para la detección de bacteriemias polimicrobianas / Evaluation of the reincubation of positive blood cultures for detection in the BACT-ALERT system for the detection of polymicrobial bacteremia

Between February and September 1997, 6588 blood cultures at the Instituto de CardiologYa y CirugYa Cardiovascular and Hospital de Niños Ricardo GutiUrrez were studied by using the Bact-Alert system (Organon Teknika) 341 contaminants and 294 episodes of bacteremia (600 samples) were analyzed. From these samples, 280 (95.3) were monomicrobial episodes and 14 (4.7) polymicrobial episodes. Positive blood cultures detected by the Bact-Alert system were processed and then reincubated during 7 days, when they were Gram stained and subcultured in blood agar, chocolate agar (both in 5-10 CO2), laked blood agar supplemented with hemin and vitamin K in anaerobic atmosphere (only anaerobic bottles) and CLDE (aerobic conditions). Following reincubation, 3 out of 14 polymicrobial bacteremias were detected, rising the level of detection from 3.7 to 4.7. Taking into account the total number of bacteremias, only in 3 out of 294 (1), a second microorganism was detected. Otherwise, in blood cultures where a contaminating microorganism was initially isolated, no further isolates representing a true bacteremia were recovered. Reincubation and terminal subculture of initially positive blood cultures did not provide relevant data in order to change therapeutic measures in the studied population. Due to the increase in costs and labor we consider that this methodology is not routinely advised.(AU)

Evaluación de la reincubación de hemocultivos positivos por el sistema BACT-ALERT para la detección de bacteriemias polimicrobianas. / [Evaluation of the reincubation of positive blood cultures for detection in the BACT-ALERT system for the detection of polymicrobial bacteremia]

Between February and September 1997, 6588 blood cultures at the Instituto de Cardiología y Cirugía Cardiovascular and Hospital de Niños Ricardo Gutiérrez were studied by using the Bact-Alert system (Organon Teknika) 341 contaminants and 294 episodes of bacteremia (600 samples) were analyzed. From these samples, 280 (95.3

) were monomicrobial episodes and 14 (4.7

) polymicrobial episodes. Positive blood cultures detected by the Bact-Alert system were processed and then reincubated during 7 days, when they were Gram stained and subcultured in blood agar, chocolate agar (both in 5-10

CO2), laked blood agar supplemented with hemin and vitamin K in anaerobic atmosphere (only anaerobic bottles) and CLDE (aerobic conditions). Following reincubation, 3 out of 14 polymicrobial bacteremias were detected, rising the level of detection from 3.7

to 4.7

. Taking into account the total number of bacteremias, only in 3 out of 294 (1

), a second microorganism was detected. Otherwise, in blood cultures where a contaminating microorganism was initially isolated, no further isolates representing a true bacteremia were recovered. Reincubation and terminal subculture of initially positive blood cultures did not provide relevant data in order to change therapeutic measures in the studied population. Due to the increase in costs and labor we consider that this methodology is not routinely advised.

Microbiology of acute arthropathies among children in Argentina: Mycoplasma pneumoniae and hominis and Ureaplasma urealyticum.

OBJECTIVE: To describe the isolation of mycoplasmas and ureaplasmas from synovial fluid in pediatric patients with joint disorders. METHODS: During 1 year 45 samples of synovial fluid, blood and urine were collected from 33 hospitalized pediatric patients up to 17 years old who had joint disorders. Mycoplasmas and ureaplasmas were isolated in joint fluid by culture methods. RESULTS: Of the 33 patients 12 (36%) had joint disorders associated with pathogens (bacteria, Mycoplasma/Ureaplasma, Chlamydia) present at the site of inflammation. Mycoplasma hominis and Ureaplasma urealyticum were isolated from 3 and 1% of joint fluid samples, respectively. M. pneumoniae was isolated from nasopharyngeal secretion in a patient with evidence of a reactive arthritis. CONCLUSION: Our results raise the question of the possible role of Mycoplasma as a cofactor in the triggering of inflammatory joint disease, as well as the hypothesis that arthropathies may be caused by chronic local infection. These findings may contribute to early diagnosis of the disease and initiation of specific treatment.