ABSTRACT
@#Trimethoprim-sulfamethoxazole is an active agent against Burkholderia pseudomallei and is being used in intensive and maintenance phases of melioidosis therapy. In this study, we evaluated the bactericidal activities of β-lactams (imipenem, ceftazidime and amoxicillinclavulanate) alone and in combinations with trimethoprim-sulfamethoxazole against B. pseudomallei. Four clinical strains of B. pseudomallei were selected based on different genotypes that are frequently found in Malaysia. The minimum inhibitory concentrations of trimethoprim-sulfamethoxazole, ceftazidime, imipenem and amoxicillin-clavulanate were determined using microdilution broth method. The bactericidal activities and synergy effects of β-lactams and/or trimethoprim-sulfamethoxazole were evaluated by checkerboard and static time-kill analyses at 1×MIC concentration of each antibiotic. Using checkerboard method, the β-lactam/trimethoprim-sulfamethoxazole combinations exhibited ΣFIC of 0.75-4.00. In time-kill analysis, ceftazidime/trimethoprim-sulfamethoxazole combination demonstrated synergy against three strains (less 2.25-2.41 log10CFU/mL compared to the most active antibiotic monotherapy) whereas imipenem/trimethoprim-sulfamethoxazole combination regimen showed synergy against one strain (less 3.32 log10CFU/mL). No antagonist effect or major re-growth was observed in all combination regimens, whereas 11 out of 12 of β-lactam monotherapy regimens were associated with re-growth of bacteria. However, all β-lactam monotherapy regimens exhibited rapid and stronger killing activities against BUPS/07/14, in the initial 12 hours compared to β-lactam/ trimethoprimsulfamethoxazole combination regimens. The combination of β-lactams with trimethoprimsulfamethoxazole demonstrated better killing effect at 24 hours compared to monotherapy and no major bacterial regrowth was observed. Nevertheless, delay in killing activities of β-lactam/trimethoprim-sulfamethoxazole combination regimens against BUPS/07/14 need further examination because this phenomenon can lead to treatment failure in some patients.
ABSTRACT
@#Spontaneous bacterial peritonitis caused by Vibrio cholerae non-O1/ non-O139 is a rare phenomenon. V. cholerae is known as a common aetiology of epidemic diarrheal disease and rarely causes extra-gastrointestinal infections. In this report, a 52-year-old man presented to our hospital with a clinical scenario for chronic liver cirrhosis with low grade fever and loose stools. V. cholerae was isolated from peritoneal fluid culture, which was further confirmed as non-O1/ non-O139 strain by multiplex polymerase chain reaction. The patient was successfully treated with antimicrobial therapy and peritoneal drainage. This case represents the first isolation of V. cholerae non-O1/ non-O139 strain from peritoneal fluid.
ABSTRACT
@#Reduced susceptibility in Burkholderia pseudomallei during carbapenem therapy may lead to treatment failure. We isolated a clinical strain that had developed reduced susceptibility to carbapenems while on treatment. After reviewing the patient’s clinical notes, the initial isolate (BUPS01/14) was exposed to carbapenem in vitro to mimic the clinical scenario. The stability of susceptibility of the carbapenem-exposed strain (BUPS01/14R) was examined by serial subculture in antibiotic-free broth. Biochemical and morphological comparison was performed by the VITEK® system and electron microscopy. MICs increased 32-fold following carbapenem exposure and became stable in the antibiotic-free environment. On electron microscopic examination, the BUPS01/14R cells were smoother and less wrinkled compared to BUPS01/14 cells. This report highlights a potential anti-melioidosis treatment failure due to the emergence of resistance while on carbapenem monotherapy. Further study of this strain is necessary to understand the mechanism of resistance at a molecular level.
ABSTRACT
@#. Candida parapsilosis is an important pathogen of healthcare-associated bloodstream infections (BSI) causing high mortality and morbidity in immunocompromised patients in addition to other Candida species including C. albicans, C. tropicalis, C. glabrata, and C. krusei. Knowledge on recent local species distribution and trend is essential. An increase in the proportion of C. parapsilosis candidemia has been recently observed as a result of many risk factors. The distribution of candidemia has been changing in the last three decades. To determine the proportion of different Candida species causing candidemia in a tertiary-care hospital during January 2001 – December 2018, a retrospective study performed in a 853-bedded tertiary-care hospital in north-eastern Malaysia. All cases of candidemia from January-2001 to December-2018 were included, and the review was performed based on patients’ medical records and laboratory database. The frequency of different Candida species was determined. This study showed that out of 1175 patients with candidemia, C. parapsilosis was the most common species contributing to 29.2% (343/1175) of candidemia, followed by C. albicans 20.1% (236/1175), C. tropicalis 18.7% (220/1175), C. glabrata 6.0% (71/1175), C. guilliermondii 3.7% (43/1175), C. rugosa 1.9% (22/1175), C. famata 1.7% (20/1175), C. krusei 1.4% (16/1175), C. dubliniensis 0.8% (9/1175), C. lusitaniae 0.7% (8/1175), C. lipolytica 0.3% (4/1175), C. pelliculosa 0.3% (4/1175), C. haemulonii, C. kefyr, C. utilis and C. inconspicua (1/1175 each). In addition, 14.9% (175/1175) belonged to Candida spp. which were not identified to species level. In conclusion, a different scenario for the proportion of Candida species with C. parapsilosis predominates over C. albicans as a nosocomial pathogen leading to candidemia has been shown in this study
ABSTRACT
@#Rapid detection of Burkholderia pseudomallei, the etiologic agent of melioidosis, allows for timely initiation of appropriate treatment and better clinical outcomes. In the current gold standard, the culture method is time consuming and suffers from low sensitivity. Meanwhile, previously reported molecular assays are fast and sensitive, but their performance on isolates from Malaysia, an endemic region of melioidosis is under reported. This study designed oligonucleotides targeting orf2 of Type III secretion system (TTSS) genes cluster for the detection of Malaysian B. pseudomallei isolates and evaluated the assay on 95 local B. pseudomallei strains, 58 other microorganisms and 71 clinical specimens from patients. The developed assay exclusively detected all tested B. pseudomallei isolates with a detection limit of 20 fg per reaction (equivalent to ~2.5 copies). Subsequent testing on clinical samples showed that the assay detected all confirmed specimens with the growth of B. pseudomallei (n = 10/10). None of the negative specimens had a detectable signal of our TTSS-orf2 assay (n = 0/61). In conclusion, the present study provides crucial preliminary data for a subsequent study and should be considered as a potential alternative to current time-consuming culture method for the detection of B. pseudomallei.
ABSTRACT
Se estudiaron 40 ninos con shigellosis, en su mayoria lactantes. En forma randomizada un grupo de 20 ninos se trato con mecillinam en dosis de 45 mgr Kg-p/dia durante 48 hrs por via intramuscular y posteriormente 60 mgr Kg-p/dia por via oral hasta completar 5 dias.El segundo grupo de 20 ninos recibio cotrimexazole (Bactrim) en dosis de 6 mgr de trimetoprim (Kg-p/dia) por via intramuscular las primeras 48 hrs y posteriormente se continuo por via oral hasta totalizar 5 dias. En cada paciente se evaluaron diariamente, mientras duro la terapia antimicrobiana parametros clinicos como caracteristica y frecuencia de las deposiciones, curva de peso, temperatura; bacteriologicos, para lo cual se efectuaron coprocultivos diarios y bioquimicos (transaminasas GP y fosfatasas alcalinas pre y post-tratamiento). El analisis de los resultados demonstro que la eficacia clinica-bacteriologica de ambos antimicrobianos fue semejante, siendo satisfactoria en aproximadamente el 80% de los casos, observandose cierta superioridad del cotrimexazole que no alcanzo a revestir significacion estadistica