Despite the recent global spread of CTX-M β-lactamases in Escherichia coli isolates from community-acquired urinary tract infections (CA-UTIs), their dissemination has been little studied in developing countries. In a 2-year prospective study, we documented the prevalence of extended-spectrum β-lactamases (ESBLs) in E. coli that were responsible for CA-UTIs in Phnom-Penh, Cambodia. Ninety-three E. coli strains were included. We observed a high prevalence of resistance to amoxicillin (88.2% of strains), cotrimoxazole (75.3%), ciprofl oxacin (67.7%), gentamicin (42.5%), and third-generation cephalosporins (37.7%). A total of 34 strains carried ESBLs, all of which were CTX-M type. CTX-M carriage was associated with resistance to fl uoroquinolones and aminoglycosides. Using repetitive extragenic palindromic-PCR, we identifi ed 4 clusters containing 9, 8, 3, and 2 strains. The prevalence of CTX-M β-lactamases has reached a critical level in Cambodia, which highlights the need for study of their spread in developing countries.
The human population history in Southeast Asia was shaped by numerous migrations and population expansions. Their reconstruction based on archaeological, linguistic or human genetic data is often hampered by the limited number of informative polymorphisms in classical human genetic markers, such as the hypervariable regions of the mitochondrial DNA. Here, we analyse housekeeping gene sequences of the human stomach bacterium Helicobacter pylori from various countries in Southeast Asia and we provide evidence that H. pylori accompanied at least three ancient human migrations into this area: i) a migration from India introducing hpEurope bacteria into Thailand, Cambodia and Malaysia; ii) a migration of the ancestors of Austro-Asiatic speaking people into Vietnam and Cambodia carrying hspEAsia bacteria; and iii) a migration of the ancestors of the Thai people from Southern China into Thailand carrying H. pylori of population hpAsia2. Moreover, the H. pylori sequences reflect iv) the migrations of Chinese to Thailand and Malaysia within the last 200 years spreading hspEasia strains, and v) migrations of Indians to Malaysia within the last 200 years distributing both hpAsia2 and hpEurope bacteria. The distribution of the bacterial populations seems to strongly influence the incidence of gastric cancer as countries with predominantly hspEAsia isolates exhibit a high incidence of gastric cancer while the incidence is low in countries with a high proportion of hpAsia2 or hpEurope strains. In the future, the host range expansion of hpEurope strains among Asian populations, combined with human motility, may have a significant impact on gastric cancer incidence in Asia.
C. neoformans strains isolated from CSF of AIDS patients in Cambodia remain susceptible in vitro to amphotericin B. These strains are less susceptible in vitro to fluconazole, 2.5% being resistant in the first year and 14% in the second year of study. Nevertheless, in vitro resistance of C. neoformans to fluconazole appeared to be linked to extended maintenance treatments.
Supplementation of micronutrients along with iron and folic acid mitigates the excess morbidity of iron-folate alone, without reducing its efficacy in correcting anemia and building iron stores. FoodLETs are a suitable vehicle to provide micronutrient supplementation to infants.
Leptospirosis is caused by pathogenic spirochetes of the genus Leptospira. Humans can be infected after exposure to contaminated urine of reservoir animals, usually rodents, regarded as typical asymptomatic carriers of leptospires. In contrast, accidental hosts may present an acute form of leptospirosis with a range of clinical symptoms including the development of Acute Kidney Injury (AKI). Chronic Kidney Disease (CKD) is considered as a possible AKI-residual sequela but little is known about the renal pathophysiology consequent to leptospirosis infection. Herein, we studied the renal morphological alterations in relation with the regulation of inflammatory cytokines and chemokines, comparing two experimental models of chronic leptospirosis, the golden Syrian hamster that survived the infection, becoming carrier of virulent leptospires, and the OF1 mouse, a usual reservoir of the bacteria. Animals were monitored until 28 days after injection with a virulent L. borgpetersenii serogroup Ballum to assess chronic infection. Hamsters developed morphological alterations in the kidneys with tubulointerstitial nephritis and fibrosis. Grading of lesions revealed higher scores in hamsters compared to the slight alterations observed in the mouse kidneys, irrespective of the bacterial load. Interestingly, pro-fibrotic TGF-β was downregulated in mouse kidneys. Moreover, cytokines IL-1β and IL-10, and chemokines MIP-1α/CCL3 and IP-10/CXCL-10 were significantly upregulated in hamster kidneys compared to mice. These results suggest a possible maintenance of inflammatory processes in the hamster kidneys with the infiltration of inflammatory cells in response to bacterial carriage, resulting in alterations of renal tissues. In contrast, lower expression levels in mouse kidneys indicated a better regulation of the inflammatory response and possible resolution processes likely related to resistance mechanisms.
BackgroundCross-resistance to quinolones and beta-lactams is frequent in Enterobacteriaceae, due to the wide use of these antibiotics clinically and in the food industry. Prescription of one of these categories of antibiotic may consequently select for bacteria resistant to both categories. Genetic mechanisms of resistance may be secondary to a chromosomal mutation located in quinolone resistance determining region of DNA gyrase or topoisomerase IV or to a plasmid acquisition. The insertion sequence ISCR1 is often associated with qnr and may favour its dissemination in Gram-negative bacteria. The aim of this study was to determine the genetic mechanism of quinolone resistance among extended-spectrum beta-lactamase-producing Enterobacteriaceae strains in the Central African Republic.FindingsAmong seventeen ESBL-producing Enterobacteriaceae isolated from urine, pus or stool between January 2003 and October 2005 in the Central African Republic, nine were resistant to ciprofloxacin (seven from community patients and two from hospitalized patients). The ESBL were previously characterized as CTX-M-15 and SHV-12. Susceptibility to nalidixic acid, norfloxacin and ciprofloxacin, and the minimal inhibitory concentrations of these drugs were determined by disc diffusion and agar dilution methods, respectively. The presence of plasmid-borne ISCR1-qnrA region was determined by PCR and amplicons, if any, were sent for sequencing. Quinolone resistance determining region of DNA gyrase gyrA gene was amplified by PCR and then sequenced for mutation characterization. We found that all CTX-M-producing strains were resistant to the tested quinolones. All the isolates had the same nucleotide mutation at codon 83 of gyrA. Two Escherichia coli strains with the highest MICs were shown to harbour an ISCR1-qnrA1 sequence. This genetic association might favour dissemination of resistance to quinolone and perhaps other antibiotics among Enterobacteriaceae.ConclusionsThis study shows that at least two mechanisms might explain the emerging resistance of Enterobacteriaceae to quinolones in the CAR. Beside the classical topoisomerase mutation, the cause may be acquisition of a plasmid-borne qnrA1. Clinicians and bacteriologists should be made aware of possible dissemination of ISCR1-qnrA1 among Enterobacteriacae.
Penicillium marneffei infection is an important disease among human immunodeficiency virus patients inPenicillium marneffei, the only known dimorphic species in the genus Penicillium, was first isolated from an organ of a bamboo rat (Rhizomyces sinensis or Rhizomyces pruinosis) (2). Penicilliosis marneffei has been recognized with increasing frequency in Southeast Asia and Southern China (15,19,20). P. marneffei infection has become the third most common opportunistic infection in AIDS patients in Southeast Asia (17,22). Penicilliosis marneffei was first reported in Cambodia in 2002 (1). We report in vitro susceptibility test results, as determined using Etest strips, for P. marneffei isolates from human immunodeficiency virus-infected patients who presented with disseminated P. marneffei infections. We include the susceptibility test results for P. marneffei isolates from the organs of bamboo rats. Our study is the first from Cambodia to report in vitro susceptibilities of clinical and bamboo rat isolates of P. marneffei to antifungal agents.P. marneffei was isolated from 29 human immunodeficiency virus-infected patients seen at Preah Bat Norodom Sihanouk Hospital, Phnom Penh, Cambodia, from 2002 to 2004. Thirteen P. marneffei isolates were isolated from blood, 12 from skin biopsy specimens, and 4 from respiratory specimens. In all cases, only one specimen type was submitted to the laboratory. Bamboo rats (Rhizomyces pruinosus) were captured in the Mondulkiri province of Cambodia. Five isolates of P. marneffei were isolated from the lungs of 10 bamboo rats. P. marneffei was identified by the appearance of the fungal colonies on Sabouraud dextrose agar at 25°C and by microscopic examination (9).One-week-old slant cultures of the mycelial form on Sabouraud dextrose agar, grown at 25°C, were flooded with deionized distilled water (10 ml/slant), and each slant was scraped with a sterile inoculation wire loop. The suspension of mycelial fragments and conidia was transferred to a glass grinder. After the grinding, a homogenous suspension was adjusted to 1 McFarland standard (11,14). To obtain inocula of the yeast form, brain heart infusion broth (Difco) was inoculated with a fungal suspension prepared from 7-dayold slant cultures. The inoculated brain heart infusion flasks were placed on a water bath shaker (150 rpm) and incubated at 37°C for 7 days, yielding a uniform growth of yeast cells. After incubation, the broth cultures were centrifuged at 15,000 ϫ g for 20 min (4°C). After the broth was discarded, the sediment was washed three times successively with sterile deionized distilled water. The washed yeast cells were suspended in deionized distilled water and adjusted to 1 McFarland standard. Etest strips (AB Biodisk, Solna, Sweden) containing amphotericin B (AMB) (0.002 to 32 g/ml), flucytosine (5FC) (0.002 to 32 g/ml), fluconazole (FLC) (0.016 to 256 g/ml), itraconazole (ITC) (0.002 to 32 g/ ml), and ketoconazole (KTC) (0.002 to 32 g/ml) were used to determine the MICs according to the manufacturer's instructio...
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