Clinical Features and CT Imaging Findings of Melioidosis Pneumonia / 中山大学学报(医学科学版)

ObjectiveTo summarize and analyze the clinical features and CT imaging findings of melioidosis pneumonia in order to increase awareness of this disease. MethodsA retrospective study was done on clinical and CT imaging data of 68 cases with melioidosis pneumonia diagnosed from January 1， 2012 to April 1， 2023. ResultsOf the 68 cases， 62 presented with acute infection and 6 chronic infection， 88.2% were male， 85.3% were native residents of Hainan， 85.3% were farmers， 77.9% had onset in summer and autumn， 66.2% had diabetes， 100% had fever as the first clinical symptom， and 88.2% were confirmed positive by blood culture. In most patients， white blood cell count， neutrophil ratio， C-reactive protein and calcitonin levels increased， while lymphocyte ratio decreased， but no statistical difference was found between acute and chronic infection groups （P > 0.05）. Of the patients， 36.8% recovered， 42.6% got better， 11.8% patients became therapy-resistant and 8.8% died. CT image showed pathomorphological changes including nodules/masses， patchy ground-glass attenuation or large patchy consolidation or all of these at the same time. Acute and chronic infection groups had significant difference in pathomorphological changes （P = 0.01）， but no statistical difference in other imaging findings. Moreover， 36.8% of the patients developed extrapulmonary infections， 8.8% of which multi-site abscess formation. ConclusionsMelioidosis Pneumonia should be considered if the patient is the sojourner from epidemic area， or has diabetes， high fever and rapid-developing disease， with additional presence of multiple inflammatory lesions in lung CT.

Epidemiological characteristics and antimicrobial resistance of 151 cases of melioidosis in Hainan Province / 中国热带医学

@#Abstract: Objective　To analyze the epidemiological characteristics of 151 cases of melioidosis and the drug resistance of Burkholderia pseudomallei (BP), in order to provide the basis for diagnosis, treatment and reasonable prevention of melioidosis. Methods　A total of 151 inpatients and outpatients from the Second Affiliated Hospital of Hainan Medical University from January 1, 2013 to August 31, 2022 were collected, and clinical specimens were submitted for examination to isolate and identify BP strains. The clinical data of 151cases of melioidosis and the drug resistance characteristics of pathogenic bacteria were retrospectively analyzed, and using SPSS26.0 software for statistical analysis. Results　Among 151 cases with BP infection, there were 138 males (91.4%) and 13 females (8.6%); the most patients were aged from 45-<60 years old, accounting for 74 cases (49.0%); melioidosis incidence was concentrated in October (19.2%), November (19.2%), August (9.9%) and July (8.6%), and; the number of confirmed cases showed an increasing trend and the time for confirmation was <10 d; Internal medicine system (31.1%), surgery system (26.5%) and intensive care department (20.5%) were the common departments for treating melioidosis; blood (49.0%), sputum (9.9%) and wound secretion (8.6%) were the main clinical specimens for detecting BP; pulmonary infection (68.2%), sepsis (35.1%) and local suppurative infection (23.8%) were the top clinical manifestations in patients with BP infection; the effective rate of treating melioidosis was 74.8%; abnormal liver function was a risk factor for the curative effect of melioidosis (χ2=5.010, P<0.05); the sensitivity rates of BP strains to sulfamethoxazole-trimethoprim (SXT), doxycycline (DOX), imipenem(IPM), ceftazidime (CAZ), amoxicillin/clavulanate (AMC) and tetracycline (TCY) were generally more than 90%, with sensitivities of 98.7%, 97.2%, 96.7%, 94.0%, 93.2% and 90.7%, respectively. Conclusions　It can be concluded that misdiagnosis or missed diagnosis of melioidosis is easy to occur, and the understanding of the epidemiological characteristics and risk factors in this area should be strengthened. The sensitivity of BP to commonly used antibiotics has shown a certain downward trend, clinical use should be standardized, and drug resistance monitoring should be strengthened to improve the efficacy of melioidosis treatment.

Characteristics analysis of epidemiological and antimicrobial resistance of 589 meliodosis bloodstream infection cases in Hainan / 中国热带医学

@#Objective　To provide data support for the prevention and control of melioidosis by analyzing epidemiological characteristics of melioidosis bloodstream infection and antibiotic resistance of its pathogen in Hainan Province from 2012 to 2021. Methods Data was collected from Hainan Antimicrobial Resistance Surveillance System, and WHONET 5.6 software was used to merge and analyze data. Results The case numbers of melioidosis bloodstream infection showed an increasing trend year by year from 2012 to 2021. The ratio of male to female patients was 4.6∶1, with 347 cases (58.91%) of patients aged 40-<60, the age group with the highest incidence. The number of cases from July to November were 424 cases (72.0%). Haikou and Sanya reported the largest case number, with 261 and 116 cases respectively. But there were no case reported from central area including Chengmai, Tunchang, Qiongzhong and Baoting. Burkholderia pseudomallei strains were isolated from both blood and other specimens in 105 of the 589 patients, with respiratory tract and wood specimens being the sites with the highest number of strains isolated other than blood; the resistance rates of Burkholderia pseudomallei to five antibiotics showed no obvious trend of change, with the lowest resistance rate to imipenem among the five drugs at 0.6%, followed by ceftazidime at 2.2%. Conclusion During the typhoon season, elderly, middle-aged male in coastal areas should pay attention to avoid or reduce their contact with mud and water. For patients with melioidosis bloodstream infection, imipenem or ceftazidime should be selected as early as possible for initial treatment.

Whitmore's disease in a diabetic patient

Burkholderia pseudomallei is a pathogen found in tropical climates. Clinically, it manifests with a wide variety of nonspecific symptoms. We present the case of a 64-year-old male patient with a his tory of controlled type 2 diabetes mellitus, stage IIIB chronic kidney disease and tuberculosis treated in 2015, who had a prolonged febrile syndrome and chest pain with ischemic electrocardiographic changes. He underwent arteriography which revealed multivessel coronary disease with an indication for open surgical treatment. On his presurgical laboratory tests a chest tomography showed an upper right mediastinal mass, and therefore his procedure was postponed. The mass was studied on an out patient basis with a negative biopsy for malignancy and microorganisms. He subsequently developed asthenia and adynamia over four months, at which time B.pseudomallei was isolated in blood cultures. He was successfully treated with a carbapenem for 15 days and is now receiving maintenance treat ment with no complications. (Acta Med Colomb 2022; 47. DOI:https://doi.org/10.36104/amc.2022.2319).

Burkhloderia pseudomallei es un patógeno propio de climas tropicales, clínicamente se mani fiesta con una amplia variedad de síntomas inespecíficos, se presenta el caso de un paciente varón de 64 años con antecedente de diabetes mellitus tipo 2 controlada, enfermedad renal crónica estadio 3b y tuberculosis tratada en 2015 que presentaba un síndrome febril prolongado y dolor torácico con cambios isquémicos en el electrocardiograma, que fue llevado a arteriografía con enfermedad coronaria multivaso, con indicación de manejo quirúrgico abierto, en sus laboratorios prequirúrgicos se encuentra tomografía de tórax masa en mediastino superior derecho, por lo que se difiere el procedimiento, esta masa es estudiada de manera ambulatoria con reporte de biopsia negativo para malignidad y microorganismos, posteriormente con astenia y adinamia de cuatro meses, donde en hemocultivos se aisló B. pseudomallei. Fue tratado con éxito con carbapenémico por 15 días, ahora está recibiendo terapia de mantenimiento sin complicaciones. (Acta Med Colomb 2022; 47. DOI:https://doi.org/10.36104/amc.2022.2319).

Establishment and evaluation of a BALBc mouse model of Burkholderia pseudomallei via nasal infection / 中国热带医学

@#Abstract: Objective To establish an animal model of BALB/c mice infected with Burkholderia pseudomallei through the nose (inhalation route), provides a reliable animal model for the follow-up studies on the virulence of melioidosis and the pathogenesis of acute melioidosis. Methods　The experiment was carried out through infecting with Burkholderia pseudomallei through the nose (inhalation route). The pathophysiological response, visceral pathological damage and bacterial colonization of the mice infected with Burkholderia pseudomallei were observed by gross anatomy, histopathology and tissue homogenate count, and the biological characteristics of the mouse model of acute melioidosis were analyzed accordingly. Then we compared the physiological responses in BALB/c mice between the Burkholderia pseudomallei and non-pathogenic Burkholderia thailandensis. Results　In the model of acute nasal infection with Burkholderia thailandensis, most death happened between the 3rd to 5th day after infection, 3×105-3×106 CFU was the suitable dose for acute fatal melioidosis model of BALB/c mice, and the medium lethal dose was about 3×104-3×105 CFU. Both gross anatomy and tissue HE staining showed that abscesses or necrosis were found in the lung, spleen and liver, especially in the spleen and lung, which was positively correlated with the challenge dose. Viable bacteria was isolated from the blood, lung, spleen and liver of Burkholderia pseudomallei-infected mice, and the bacteria account colonization was related to tissue specificity. The concentration of live bacteria isolated from in the blood was the highest [Log2 value: (10.28±0.34) CFU/mL], and the organ with the maximum quantity of bacteria was the lung [Log2 value: (7.54±2.11) CFU/total organ]. It has been reported that the biological effects of Burkholderia pseudomallei and its homologous non-pathogenic Burkholderia thailandensis were similar at the cellular level, like multi-nuclear giant cell formation and active intracellular replication, while it is still unclarrified in the differences of virulence in mice. In this study, it was proved that Burkholderia thailandensis was not fatal to mice even at a high dose (8×107CFU), or detected from mice infected with it via nasal. Conclusion　We successfully established a reliable BALB/c mouse model (acute lethal model) of melioidosis via nasal infection, described its biological characteristics, and identified the different biological responses between Burkholderia pseudomallei and its homologous non-pathogenic Burkholderia thailandensis in mice.

Epidemiological and clinical characteristics of melioidosis in Haikou City in 2000 - 2020 / 中华地方病学杂志

Objective:To understand the epidemiological and clinical characteristics of melioidosis in Haikou City, to rise the people's awareness of melioidosis and to provide basis for prevention and control of the disease.Methods:The clinical data of 254 patients with melioidosis treated in 4 Class A tertiary hospitals in Haikou City from January 2000 to September 2020 were collected, and the epidemiological characteristics, clinical manifestations, infection site, prognosis and drug sensitivity were retrospectively analyzed.Results:Among 254 patients with melioidosis, 226 males (88.98%) and 28 females (11.02%), and the gender ratio was 8.07 ∶ 1.00. Farmers were the main occupation, accounting for 37.80% (96/254). The median age was 53 years old, mainly in 41 - 80 years old, accounting for 83.46% (212/254). Han nationality was the most, accounting for 89.76% (228/254). The onset season was mainly in summer and autumn, and the peak was from August to October (117 cases). Patients were mainly distributed in coastal areas, among which Haikou City (49 cases) was the most, followed by Dongfang City (46 cases), Danzhou City (23 cases) and Wenchang City (21 cases). Totally 196 cases (77.17%) had basic diseases, diabetes was the most common (162 cases). The main symptoms of admission were fever (211 cases), followed by cough (108 cases) and expectoration (88 cases). The infection sites were mainly blood (104 cases, 40.94%), lung (60 cases, 23.62%), liver and spleen (32 cases, 12.60%). Totally 195 patients were treated with sensitive antibiotics, at discharge, 37 cases (18.97%) were cured, 129 cases (66.15%) improved, 18 cases (9.23%) did not heal, 7 cases (3.59%) died and 4 cases (2.05%) were discharged voluntarily. Results of drug sensitivity tests from 2010 to 2020 showed that the sensitivity rates of Burkholderia pseudomallei to imipenem (142 cases), meropenem (16 cases) and ceftazidime (141 cases) were all 100.00%, and the sensitivity rates of doxycycline (25 cases) and compound sulfamethoxazole (142 cases) were 92.00% (23/25) and 99.30% (141/142), respectively. Conclusions:Males, farmers, middle-aged and elderly people and people with diabetes and other basic diseases are the high incidence population of melioidosis in Haikou City. The incidence peak is in summer and autumn. The common clinical manifestations are fever, pulmonary infection, abscess of liver and spleen, etc. In the treatment, Burkholderia pseudomallei is more sensitive to imipenem, meropenem and ceftazidime.

In-vitro activity of β-lactams/trimethoprim-sulfamethoxazole combinations against different strains of Burkholderia pseudomallei

@#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.

Melioidosis con endocarditis de válvula protésica / Prosthetic valve endocarditis in melioidosis: case report

Resumen La melioidosis es endémica en varias regiones, con predominio en el Sudeste Asiático, norte de Australia, sur de Asia, China y Taiwán. En Sudamérica, Colombia ocupa el segundo lugar de casos de melioidosis, después de Brasil. Su manifestación clínica es variable, desde una infección asintomática hasta un compromiso multiorgánico con formación de abscesos múltiples y choque séptico. El compromiso cardiaco es inusual, con una incidencia menor del 1%. Se presenta el caso de un varón de 51 años, colombiano, con antecedente de una valvula aórtica mecánica, quien presentó un absceso en la pierna derecha y en la válvula cardiaca protésica, aislándose Burkholderia pseudomallei en hemocultivos y en el cultivo de secreción de la pierna. Fue tratado con meropenem y cotrimoxazol, con una adecuada respuesta clínica, requiriendo un reemplazo valvular aórtico.

Abstract Melioidosis is an endemic disease to several regions and occurs predominantly in Southern Asia, Northern Australia, China and Taiwan. In South America, Colombia is second after Brazil in number of melioidosis cases reported. Clinical manifestation varies from asymptomatic infection to multiorgan compromise involving multiple abscesses and septic shock. Cardiac compromise is infrequent, with an incidence of <1%. We report the case of a 51-year-old patient from Colombia with a mechanical aortic valve who had an abscess in right leg and in the prosthetic valve. Burkholderia pseudomallei was isolated in blood cultures and drained pus from the leg cultures. Patient was treated with meropenem and cotrimoxazole and required aortic valve replacement, resulting in adequate improvement in clinical symptoms.

Release of pro-inflammatory cytokines TNF-α, IFN-γ and IL-6 by Burkholderia pseudomallei- stimulated peripheral blood mononucleocytes of acute myeloid leukemia patients

@#Acute myeloid leukemia (AML) is a malignant disease progressed from abnormal production of immature myeloid cells, which is often associated with concurrent infections after diagnosis. It was widely established that infections are the major contributors to mortality in this group due to the prevalency of neutropenia. Gram-negative Burkholderia pseudomallei is the causative agent of melioidosis. This disease had been reported in several neutropenic cancer patients undergoing chemotherapy resulting in severe clinical presentations and high mortalities which is in need of critical attention. Studies show that cytokines are important mediators of melioidosis progression and low neutrophil counts are associated with progression of its severity. However, to date, there are no reports on cytokine production in neutropenic cancer patients who are prone to melioidosis. Hence, here we assessed the cytokine production in neutropenic AML patients by introducing B. pseudomallei to their peripheral blood mononuclear cell (PBMC) culture in vitro. We observed that inflammatory response related cytokines namely TNF-α, IFN-γ IL-6 and IL-10 were highly circulated in infected PBMCs suggesting that these cytokines may play important roles in the progression of severity in melioidosis infected neutropenic patients.

Occurrence and Antibiotics Resistance Signatures of Burkholderia Pseudomallei Isolated from Selected Hospital Final Effluents in Akoko Metropolis within Ondo State Nigeria

@#Introduction Burkholderia pseudomallei are the causative agent for melioidosis, a disease which affects both humans and animals. This study investigated the occurrence of Burkholderia pseudomallei in the final effluent of some hospitals in Akoko metropolis, Ondo State, Nigeria. Methods Culture based approach using the Inositol Brilliant Green Bile agar for isolation Burkholderia Pseudomallei was employed. A preliminary oxidase strip test was carried out on all the isolates and they were found to be oxidase positive. Presumptive isolates were purified and confirmed using Microbact™ 24E Identification kit. Antibiotics susceptibility of the confirmed isolates was also determined using the CLSI recommended first line antibiotics for Burkholderia Pseudomallei. Results A total number of 155 presumptive Burkholderia species were recovered from thirty six different samples over a period of three months from effluent of three selected hospitals. Moreover, 67% of the recovered isolates were confirmed to be Burkholderia pseudomallei. Most isolates were susceptible to cefotaxime and ofloxacin but exhibited resistance against tetracycline and meropenem. Conclusions The persistence of Burkholderia pseudomallei in the hospital environment throughout the sampling regime requires intervention strategies to eradicate the prevalence of this notable pathogen in all possible reservoirs within the hospital environment. Besides, the emergence of resistance particularly to tetracycline and carbapenems points at potential public health implications. Furthermore, surveillance of Burkholderia species with its antibiogram profiles in clinical environments and adequate treatment of hospital effluents before disposal is very important to avert potential outbreak of melioidosis because the main reservoir for B. pseudomallei is contaminated environments. Keywords

Chronic Osteomyelitis of the Tibia Caused by Burkholderia pseudomallei: A Case Report and Review of Literature

@#Osteomyelitis accounts for the majority of bone infections with open fractures have higher rates of osteomyelitis in contrast to closed fractures. It is usually seen in open fractures with substantial contamination and soft tissue damage, as well as after internal fixation. Chronic osteomyelitis is recognised by continuance presence of microorganisms, sequestrum, low-level of inflammation and fistulae. The infection can be contained to the bone or spread to the soft tissues, periosteum, and bone marrow. The predominant aetiological agents are Staphylococcus aureus, Streptococcus species, Enterococcus species, Pseudomonas aeruginosa and Enterobacteriaceae, but rarely due to Bukholderia pseudomallei. We report a case of post-traumatic chronic osteomyelitis of tibia due to Bukholderia pseudomallei. This case emphasises the significance of considering melioidosis in patients with uncontrolled diabetes mellitus who have undergone surgical intervention and reside in a region where infectious diseases are prevalent.

Partial characterization of bacteriocin-like compound (BLIS) produced by Burkholderia stagnalis strain K23/3 against Burkholderia pseudomallei

Aims@#Burkholderia pseudomallei, the human pathogen that causes melioidosis, is intrinsically resistant towards a wide range of antibiotics and there have been reports of acquired resistance towards antibiotics used for melioidosis treatments. Antimicrobial peptides (AMP) such as bacteriocins are gaining the interests of researchers as alternative for treating infections caused by multidrug resistant bacteria. In this study, we aimed to identify Burkholderia spp. isolated from soil in Sarawak that possess the potential in inhibiting the growth of B. pseudomallei and to further characterize the antagonistic compound produced.@*Methodology and results@#A total of 50 Burkholderia spp. isolates of environmental origin and two isolates of Ralstonia solanacearum were screened against five clinical isolates of B. pseudomallei using spot-on-lawn assay and flip streak method. Burkholderia stagnalis isolate K23/3 showed clear zones of inhibition (ZOI) in both preliminary tests. Cell-free supernatant (CFS) was obtained from B. stagnalis K23/3 broth culture and was tested via agar well diffusion assay (AWDA). The antagonistic compound secreted at the early log phase of the bacterial growth was shown to be stable in a wide range of temperatures and pH. Treatment with different enzymes revealed that it was sensitive towards proteinase K, suggesting that it is proteinaceous. The bacteriocin-like-substance (BLIS) was subjected to ammonium sulfate precipitation and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The SDS-PAGE gel was overlaid with indicator B. pseudomallei isolates where the active protein was shown to be less than 7.1 kDa.@*Conclusion, significance and impact of study@#Burkholderia stagnalis isolate K23/3 was able to secrete bacteriocin-like-substance (BLIS) that has the potential in biocontrol of B. pseudomallei in the environment or as potential treatment for melioidosis.

Trend and pattern of melioidosis seropositivity among suspected patients in Malaysia 2015 – 2019

@#Melioidosis is a disease of public health importance associated with high case-fatality rates in animals and humans caused by Burkholderia pseudomallei (B. pseudomallei), a gramnegative bacterium that lives in tropical soil environments. This study determined the seropositivity for melioidosis among patients admitted to healthcare centres in Malaysia, from 2015 to 2019 and identified factors related to it. A total of 26,665 serum samples of suspected melioidosis patients from Malaysia hospitals were tested for IgM against B. pseudomallei. About 16.4% of total samples were seropositive and majority of them were 55 years old and above. However, younger people aged less than 15 years old were the most susceptible to the infection (AOR 3.04, p <0.001, 95% CI: 2.73, 3.39). Melioidosis infection was the highest in Sarawak (15.1%) while Perlis was the least exposed to the infection (0.9%). Further analyses showed that patients with chronic lung disease (adjusted OR: 4.03, p < 0.001, 95% CI: 2.77, 5.86) were more susceptible to melioidosis infection. In conclusion, although serology testing is not a gold standard test in diagnosing melioidosis, it has been used as a tool in treatment monitoring and disease surveillance among patients and at-risk community in the endemic hot-spots regions.

Antibacterial activity of bacillomycin D-like compounds isolated from Bacillus amyloliquefaciens HAB-2 against Burkholderia pseudomallei

Objective: To investigate the inhibitory effect on Burkholderia pseudomallei (B. pseudomallei) strain HNBP001 of a bacillomycin D-like cyclic lipopeptide compound named bacillomycin DC isolated from Bacillus amyloliquefaciens HAB-2. Methods: The antibacterial effect of bacillomycin DC on B. pseudomallei was determined using the disk diffusion method. The minimum inhibitory concentrations were evaluated by microdilution assay. In addition, transmission electron microscopy was performed and quantitative real-time polymerase chain reaction assay was carried out to determine the expression of MexB, OprD2, and qnrS genes. Results: Bacillomycin DC produced an inhibition zone against B. pseudomallei with minimum inhibitory concentration values of 12.5 μg/mL 24 h after treatment and 50 μg/mL at 48 and 72 h. Transmission electron microscopy showed that bacillomycin DC resulted in roughening cell surface and cell membrane damage. Quantitative real-time polymerase chain reaction analysis showed low expression of MexB, OprD2 and qnrS genes. Conclusions: Bacillomycin DC inhibits the growth of B. pseudomallei and can be a new candidate for antimicrobial agents of B. pseudomallei.

Antibacterial activity of bacillomycin D-like compounds isolated from Bacillus amyloliquefaciens HAB-2 against Burkholderia pseudomallei

Objective: To investigate the inhibitory effect on Burkholderia pseudomallei (B. pseudomallei) strain HNBP001 of a bacillomycin D-like cyclic lipopeptide compound named bacillomycin DC isolated from Bacillus amyloliquefaciens HAB-2. Methods: The antibacterial effect of bacillomycin DC on B. pseudomallei was determined using the disk diffusion method. The minimum inhibitory concentrations were evaluated by microdilution assay. In addition, transmission electron microscopy was performed and quantitative real-time polymerase chain reaction assay was carried out to determine the expression of MexB, OprD2, and qnrS genes. Results: Bacillomycin DC produced an inhibition zone against B. pseudomallei with minimum inhibitory concentration values of 12.5 μg/mL 24 h after treatment and 50 μg/mL at 48 and 72 h. Transmission electron microscopy showed that bacillomycin DC resulted in roughening cell surface and cell membrane damage. Quantitative real-time polymerase chain reaction analysis showed low expression of MexB, OprD2 and qnrS genes. Conclusions: Bacillomycin DC inhibits the growth of B. pseudomallei and can be a new candidate for antimicrobial agents of B. pseudomallei. Rajaofera Mamy 1 Key Laboratory of Tropical Translational Medicine of Ministry of Education and School of Tropical Medicine and Laboratory Medicine, Hainan Medical University, Haikou, Hainan Kang Xun 2 Key Laboratory of Tropical Translational Medicine of Ministry of Education and School of Tropical Medicine and Laboratory Medicine, Hainan Medical University, Haikou, Hainan Jin Peng-Fei 3 Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests (Hainan University), Ministry of Education, Haikou 570228, Hainan Chen Xin 4 Key Laboratory of Tropical Translational Medicine of Ministry of Education and School of Tropical Medicine and Laboratory Medicine, Hainan Medical University, Haikou, Hainan Li Chen-Chu 5 Key Laboratory of Tropical Translational Medicine of Ministry of Education and School of Tropical Medicine and Laboratory Medicine, Hainan Medical University, Haikou, Hainan Yin Li 6 Key Laboratory of Tropical Translational Medicine of Ministry of Education and School of Tropical Medicine and Laboratory Medicine, Hainan Medical University, Haikou, Hainan Liu Lin 7 Key Laboratory of Tropical Translational Medicine of Ministry of Education and School of Tropical Medicine and Laboratory Medicine, Hainan Medical University, Haikou, Hainan Sun Qing-Hui 8 Key Laboratory of Tropical Translational Medicine of Ministry of Education and School of Tropical Medicine and Laboratory Medicine, Hainan Medical University, Haikou, Hainan Zhang Nan 9 Key Laboratory of Tropical Translational Medicine of Ministry of Education and School of Tropical Medicine and Laboratory Medicine, Hainan Medical University, Haikou, Hainan Chen Chui-Zhe 10 Key Laboratory of Tropical Translational Medicine of Ministry of Education and School of Tropical Medicine and Laboratory Medicine, Hainan Medical University, Haikou, Hainan He Na 11 Key Laboratory of Tropical Translational Medicine of Ministry of Education and School of Tropical Medicine and Laboratory Medicine, Hainan Medical University, Haikou, Hainan Xia Qian-Feng 12 Key Laboratory of Tropical Translational Medicine of Ministry of Education and School of Tropical Medicine and Laboratory Medicine, Hainan Medical University, Haikou, Hainan Miao Wei-Guo 13 Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests (Hainan University), Ministry of Education, Haikou 570228, Hainan Kung CT, Lee CH, Li CJ, Lu HI, Ko SF, Liu JW. 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Melioidosis in Odisha: A clinico-microbiological and epidemiological description of culture-confirmed cases over a 2-year period

Melioidosis is an emerging infectious disease in India mostly reported from South-western coastal Karnataka and North-eastern Tamil Nadu. We speculate the existence of another major hidden focus in Odisha, one of the eastern coastal states. The clinico-epidemiological features of 47 culture-confirmed melioidosis at a tertiary care teaching hospital over a period of 2 years are reported. Septicaemia was the most common clinical presentation. Diabetes mellitus (DM) was present in 72.3% of our cases. The geo-climatic conditions of Odisha and other coastal states of India and the rise in the incidence of DM demand a nationwide surveillance of melioidosis and creation of melioidosis registry.

Melioidosis en Colombia, descripción de un caso clínico y consideraciones epidemiológicas / Melioidosis in Colombia, description of a clinical case and epidemiological considerations

Resumen La melioidosis es una enfermedad infecciosa causada por Burkholderia pseudomallei cuyo diagnóstico clínico puede ser difícil debido a su variada presentación clínica y a las dificultades del diagnóstico microbiológico, por lo cual pueden requerirse técnicas moleculares para su adecuada identificación una vez se sospecha su presencia. Son pocos los antibióticos disponibles para el tratamiento de esta enfermedad y, además, deben usarse durante un tiempo prolongado. Aunque se conoce por ser endémica en Tailandia, Malasia, Singapur, Vietnam y Australia, en Colombia se han reportado algunos pocos casos. Se presenta un caso de melioidosis en la región norte de Colombia, se hace una revisión de las características clínicas y el tratamiento, y se describe la epidemiología local de esta enfermedad.

Abstract Melioidosis is an infectious disease caused by Burkholderia pseudomallei whose clinical diagnosis can be difficult due not only to its varied clinical presentation but also to the difficulties in the microbiological diagnosis.Thus, it may be necessary to use molecular techniques for its proper identification once it is suspected. There are few antibiotics available for the treatment of this disease, which must be used over a long period of time. Although it is known to be endemic in Thailand, Malaysia, Singapore, Vietnam, and Australia, in Colombia there are few reported cases. We describe a case of melioidosis in the northern region of Colombia. Additionally, we review its clinical characteristics and treatment and we describe the local epidemiology of this disease.

Multilocus sequence typing characteristics of the pathogenic strain of Burkholderia pseudomallei in Hainan / 中华地方病学杂志

Objective To understand the pathogenicity and multilocus sequence typing (MLST) characteristics of the pathogenic strain of Burkholderia pseudomallei (Bp) in Hainan,and provide a reference for studying the structural characteristics and phylogenetic characteristics of pathogenic Bp in Hainan.Methods The data of patients with melioidosis in Hainan,who were treated in Hainan General Hospital from 2011 to 2018,and Bp pathogenic strains isolated from patient infected specimens were collected.The Bp pathogenic strains were genotyped by MLST method,and the distribution characteristics of the sequence type (ST) were analyzed.The ST of all Bp pathogenic strains was analyzed by eBURST v3 software to establish the evolutionary relationship map.Results A total of 91 cases of melioidosis patients were studied,including 76 males and 15 females;the ages were mainly concentrated in 40-70 years old;clinical manifestations included sepsis,pulmonary infection and local abscess;and the most common diseases were diabetes.A total of 91 Bp pathogenic strains were observed,of which 85 Bp pathogenic strains were distributed in coastal areas of Hainan,accounting for 93.41％;identified by MLST method,39 ST were discovered,the most common were ST46 (13 strains),ST55 (12 strains),STS0 (8 strains) and ST58 (7 strains),accounting for 14.29％,13.19％,8.79％ and 7.69％,respectively;except ST46 was widely distributed in the coastal areas of Hainan,the ST55,ST50 and ST58 were concentrated in the southwest,northeast and southeast regions of Hainan.Compared with the MLST database,ST30 (3 strains) was currently found only in Hainan,ST562 (4 strains) had been reported in northern Australia,and the remaining ST models had been reported in southeast Asia.The eBURST v3 software divided the 39 ST into 3 subtypes and 18 individual types.Among them,the subtypes with ST300 as the original type had the most number of ST,including 17 ST,57 Bp pathogenic strains;compared with the MLST database,the ST300 was mainly distributed in southeast Asian regions such as Thailand.Conclusions The ST of Bp pathogenic strains in Hainan has high regional diversity and genetic diversity,and is closely related to Bp in southeast Asian regions such as Thailand.

A 5-year retrospective study of melioidosis cases treated in a district specialist hospital

@#INTRODUCTION: Melioidosis is caused by Burkholderia pseudomallei, a gram-negative aerobic bacillus, found in the soil and surface water. Treating melioidosis has been a challenge in district hospitals due to high usage of broad spectrum antibiotics and prolonged hospitalisation. This study is to review the patients’ demography, clinical presentations and microbiological data. METHODS: A 5-year retrospective study was carried out on patients admitted with culture positive for melioidosis from year 2013 to 2017 in Hospital Teluk Intan, Perak. RESULTS: There were a total of 46 confirmed cases of melioidosis. Majority of the patients were working in the agricultural and farming (28.6%), and factories (25.7%). Thirty-one patients had diabetes mellitus (71.1%). Presentations of patients with melioidosis included pneumonia (54.3%), skin and soft tissue infection (19.6%), deep abscesses (15.2%) and bone and joint infections (13%). An average of 5.8 days was needed to confirm the diagnosis of melioidosis via positive culture. However, only 39.4% of these patients were started on ceftazidime or carbapenem as the empirical therapy. The intensive care unit (ICU) admission rate for melioidosis was 46% and the mortality rate was 52%. Our microbial cultures showed good sensitivity towards cotrimoxazole (97.1%), ceftazidime (100%) and carbapenem (100%). CONCLUSION: Melioidosis carries high mortality rate, especially with lung involvement and bacteremia. Physicians should have high clinical suspicion for melioidosis cases to give appropriate antimelioidosis therapy early

A case of septicaemic melioidosis: Utility of therapeutic drug monitoring and high-dose meropenem in successful management

Melioidosis is an emerging infectious disease of major public health importance. We describe a patient who presented with septicaemic melioidosis with multi-organ dysfunction. He had only marginal response on standard doses of meropenem. Therapeutic drug monitoring (TDM) revealed suboptimal concentration of meropenem following which drug dose was increased, with which he showed rapid clinical improvement and microbiological clearance. Melioidosis presents with multisystem involvement with disseminated abscess, standard dosing of meropenem may not be sufficient in achieving therapeutic levels and TDM with increased dosing in these critically ill patients will improve outcome.