Mycotic aneurysm secondary to melioidosis in China: A series of eight cases and a review of literature

The Epidemiological, Clinical, and Microbiological Features of Patients with Burkholderia pseudomallei Bacteraemia-Implications for Clinical Management

Patients with melioidosis are commonly bacteraemic. However, the epidemiological characteristics, the microbiological findings, and the clinical associations of Burkholderia pseudomallei bacteraemia are incompletely defined. All cases of culture-confirmed melioidosis at Cairns Hospital in tropical Australia between January 1998 and June 2023 were reviewed. The presence of bacteraemia was determined and correlated with patient characteristics and outcomes; 332/477 (70%) individuals in the cohort were bacteraemic. In multivariable analysis, immunosuppression (odds ratio (OR) (95% confidence interval (CI)): (2.76 (1.21-6.27), p = 0.02), a wet season presentation (2.27 (1.44-3.59), p < 0.0001) and male sex (1.69 (1.08-2.63), p = 0.02), increased the likelihood of bacteraemia. Patients with a skin or soft tissue infection (0.32 (0.19-0.57), p < 0.0001) or without predisposing factors for melioidosis (0.53 (0.30-0.93), p = 0.03) were less likely to be bacteraemic. Bacteraemia was associated with intensive care unit admission (OR (95%CI): 4.27 (2.35-7.76), p < 0.0001), and death (2.12 (1.04-4.33), p = 0.04). The median (interquartile range) time to blood culture positivity was 31 (26-39) hours. Patients with positive blood cultures within 24 h were more likely to die than patients whose blood culture flagged positive after this time (OR (95%CI): 11.05 (3.96-30.83), p < 0.0001). Bacteraemia portends a worse outcome in patients with melioidosis. Its presence or absence might be used to help predict outcomes in cases of melioidosis and to inform optimal clinical management.

Serodiagnosis of Abdominal Abscess Caused by Burkholderia pseudomallei: Case Report and Literature Review

Burkholderia pseudomallei, the causative agent of melioidosis can be responsible for a wide spectrum of clinical manifestations and heterogeneous prognoses, with a high mortality in the acute onset. We report a case of a deep abdominal abscess with sepsis secondary to melioidosis in a young farmer from a non-high-risk population. Emergency medical treatment was administered according to the detection of serum antibodies against Hcp1, the results of which provided etiological evidence of B. pseudomallei infection for the timely and properly antimicrobial therapy in the absence of direct evidence of melioidosis. To our knowledge, this is the first reported case of serodiagnosis of acute exacerbation of melioidosis in China.

Endovascular Treatment for Isolated Infected Iliac Artery Aneurysms

PURPOSE

Isolated infected iliac artery aneurysms (IIIAAs) are extremely rare, life-threatening, and intractable. This study aimed to evaluate the outcomes of endovascular treatment in patients with IIIAAs.

METHODS

A retrospective study was conducted for all patients who underwent endovascular treatment for IIIAAs between June 2012 and June 2022 in 3 hospitals. The clinical data and follow-up outcomes were reviewed and assessed.

RESULTS

Fifteen patients were included in this study. The median age was 69 years, 12 patients (80%) were men, and 8 (53%) had hypertension. Most of the patients presented with abdominal or lumbar pain (87%) and fever (60%). The offending pathogen was identified in 11 patients (73%). Fifteen patients had a total of 16 IIIAAs, with 12 (75%) involving the common iliac artery. The immediate technical success rate was 100%, and the 30-day mortality was 7%. Infection-related complications occurred in 2 patients (13%) during hospitalization who were treated by open surgery at a later stage. The median follow-up was 23 months (range: 6-80 months, mean: 32 ± 25 months). Aneurysm recurrence was identified in one patient (7%) 5 months after endovascular repair. It was managed by endovascular stent-graft repair with percutaneous catheter drainage. No patients died during the follow-up period.

CONCLUSION

Endovascular treatment is feasible, safe, and effective for patients with IIIAAs, achieving acceptable clinical outcomes. Infection surveillance with essential reintervention should be considered for potential infection-related complications.

CLINICAL IMPACT

This study first reported that 15 patients underwent endovascular treatment for primary isolated infected iliac artery aneurysms (IIIAAs). It showed a good early and midterm outcomes. This is the first and largest multi-center study and the first literature review of IIIAAs. It provides an evidence that endovascular treatment is feasible, safe, and effective to treat IIIAAs. It suggests endovascular treatment is a promising alternative or a bridge to conventional open surgery for IIIAAs. This may promote endovascular therapy in the management of IIIAAs. It would help clinicians to make an appropriate treatment choice for IIIAAs.

Chronic Splenic Melioidosis in a Patient with Fever of Unknown Origin Diagnosed by Metagenomics Next-Generation Sequencing: An Emerging Cause and Literature Review

Introduction

Human melioidosis is an emerging infectious disease in tropical areas of China, and chronic melioidosis can be a rare cause of fever of unknown origin (FUO). Timely diagnosis may improve the prognosis of melioidosis.

Case Presentation

We report a case of melioidosis with splenic abscesses caused by Burkholderia pseudomallei in a 57-year-old man, who presented with FUO. Positron emission tomography/computed tomography (PET/CT) revealed multiple hypermetabolic lesions in the spleen. The spleen biopsy was conducted and metagenomics next-generation sequencing (mNGS) of the spleen specimen identified the presence of B. pseudomallei, confirming the diagnosis of melioidosis. Antimicrobial treatment was initiated with intravenous meropenem, followed by oral faropenem. During the follow-up, the patient was in good condition except having a low-grade fever occasionally. A splenectomy was performed, and subsequent culture and mNGS of the spleen pus were both positive for B. pseudomallei. Histopathological characteristics of chronic splenic melioidosis were noted.

Conclusion

Melioidosis is a serious endemic disease, and it is critical to raise awareness about this disease.

A case of Burkholderia pseudomallei mycotic aneurysm linked to exposure in the Caribbean via whole genome sequencing

Melioidosis, an infection caused by Burkholderia pseudomallei, has a very high risk of mortality when treated, with an even higher risk of fatality if undiagnosed or not treated appropriately. It is endemic to Asia, Australia, South America, and the Caribbean; however, the number of melioidosis cases reported in the United States has been increasing. Therefore, physicians should be aware of this clinical entity and its possible presentations. Mycotic aneurysms due to B. pseudomallei are extremely rare accounting for approximately 1-2% of cases. Here we describe a rare case of melioidosis presenting as a mycotic aneurysm in the United States; highlight the potential for diagnostic challenges and epidemiologic concerns; as well as provide a review of mycotic aneurysm cases due to B. pseudomallei published to date.

Melioidosis-related mycotic aneurysm: Three cases

Background

Melioidosis-related mycotic aneurysm (MA) is rare but a potentially life-threatening disease with high morbidity and mortality rate.

Case presentation

We report a case series of mycotic aneurysm caused by Burkholderia pseudomallei and the subsequent outcomes. Here, we illustrate their clinical characteristics, laboratory results, radiological findings, mode of therapies and clinical outcomes.

Conclusion

Melioidosis-associated MA may manifest in an atypical presentation. Its outcome is often lethal if antimicrobial therapy and surgical intervention are not offered promptly.

Osteomyelitis and Septic Arthritis Due to Burkholderia pseudomallei: A 10-Year Retrospective Melioidosis Study From South China

Burkholderia pseudomallei is the causative agent of melioidosis, endemic mainly in tropical and subtropical areas. Its clinical manifestation is broad ranging from a localized skin lesion to a life-threatening systemic disease. Osteomyelitis and septic arthritis caused by B. pseudomallei are a rare, fatal illness, whose clinical features have not been illustrated in mainland China. Over 10 years (2010 to 2019), of 334 culture-confirmed melioidosis in Hainan province, China, 44 patients (13.2%) were confirmed to have osteomyelitis and septic arthritis through the combination of clinical features, imaging examination and microbiological culture. Herein, we summarized these 44 patients' clinical manifestations, demographical features, antibiotic treatment, and outcomes. Of them, osteomyelitis and septic arthritis accounted for 25 (56.8%) and 15 (34.1%), respectively, and 4 patients (9.1%) had both. The gender ratio of male/female was approximately 13.7:1; diabetes mellitus was the most common risk factor (38/44, 86.4%); imipenem and trimethoprim/sulfamethoxazole were the most frequently used antibiotics. Most B. pseudomallei strains were isolated from blood samples (41/44, 93.2%). After surgical handling, antibiotic treatment, or both, 9 patients died, with a mortality rate of 20.5%. In summary, in melioidosis endemic areas, for patients with both localized manifestations of joint and bone and a positive B. pseudomallei blood culture, increased awareness is required for melioidotic osteomyelitis and septic arthritis.