Bacteremia caused by extended-spectrum beta-lactamase–producing Enterobacteriaceae in Vientiane, Lao PDR: a 5-year study

Although there has been an increasing incidence of bacteremia caused by extended-spectrum beta-lactamase (ESBL)&ndash;producing Enterobacteriaceae (ESBL-E) across South East Asia, there are sparse data from the Lao PDR, where laboratory capacity for antimicrobial resistance surveillance is limited. We, therefore, retrospectively reviewed bacteremia caused by ESBL-producing&nbsp;Escherichia coli&nbsp;and&nbsp;Klebsiella pneumoniae&nbsp;between 2010 and 2014 at Mahosot Hospital, Vientiane, Lao PDR. Clinical and laboratory data relating to all episodes of ESBL-E bacteremia were reviewed over the 5-year period and compared with non&ndash;ESBL-E bacteremia. Blood cultures positive for&nbsp;E. coli&nbsp;or&nbsp;K. pneumoniae&nbsp;were identified retrospectively from laboratory records. Clinical and laboratory data were extracted from research databases and case notes and analyzed using STATA. Between 2010 and 2014, we identified 360 patients with&nbsp;E. coli&nbsp;(n&nbsp;= 249) or&nbsp;K. pneumoniae&nbsp;(n&nbsp;= 111) bacteremia, representing 34.8% of all patients with clinically significant bacteremia.&nbsp;Seventy-two (20%) isolates produced ESBL;&nbsp;E. coli&nbsp;accounted for 15.3% (55/360) and&nbsp;K. pneumoniae&nbsp;for 4.7% (17/360), respectively. The incidence of ESBL-producing&nbsp;E. coli&nbsp;bacteremia rose during the study period. By multiple logistic analysis, reported antibiotic use in the previous week was significantly associated with ESBL positivity (P&nbsp;&lt; 0.001, odds ratio 3.89). Although multiresistant, most ESBL-producing&nbsp;E. coli&nbsp;and&nbsp;K. pneumoniae&nbsp;remained susceptible to meropenem (65/65; 100%) and amikacin (64/65; 98.5%). We demonstrated an alarming increase in the incidence of ESBL-E as a cause of bacteremia in Vientiane during the study period. This has implications for empiric therapy of sepsis in Laos, and ongoing surveillance is essential.</p

Molecular detection of pathogens in negative blood cultures in the Lao People’s Democratic Republic

Bloodstream infections cause substantial morbidity and mortality. However, despite clinical suspicion of such infections, blood cultures are often negative. We investigated blood cultures that were negative after 5 days of incubation for the presence of bacterial pathogens using specific (Rickettsia spp. and Leptospira spp.) and a broad-range 16S rRNA PCR. From 190 samples, 53 (27.9%) were positive for bacterial DNA. There was also a high background incidence of dengue (90/112 patient serum positive, 80.4%). Twelve samples (6.3%) were positive for Rickettsia spp., including two Rickettsia typhi. The 16S rRNA PCR gave 41 positives; Escherichia coli and Klebsiella pneumoniae were identified in 11 and eight samples, respectively, and one Leptospira species was detected. Molecular investigation of negative blood cultures can identify potential pathogens that will otherwise be missed by routine culture. Patient management would have been influenced in all 53 patients for whom a bacterial organism was identified, and 2.3–6.1% of patients would likely have had an altered final outcome. These findings warrant further study, particularly to determine the cost–benefit for routine use, ways of implementation, and timing of PCR for organisms such as Rickettsia and Leptospira, which are important pathogens in rural Asia