Two Norwegian patients with melioidosis presenting with bacteraemia and splenic and prostatic abscesses

A review of melioidosis cases imported into Europe

Melioidosis is a tropical bacterial infection, rarely encountered, and poorly known by clinicians. In non-endemic areas, a misdiagnosis can lead to a fatal outcome. This study aims to identify the main characteristics of imported and diagnosed melioidosis cases in Europe to increase clinician's awareness of this diagnosis. A literature review of imported and diagnosed human melioidosis cases in Europe was performed. PubMed and Web of Science search engines were used for retrieving articles from 2000 to November 2018. Seventy-seven cases of imported melioidosis into Europe described in the literature were identified. More than half of the cases were acquired in Thailand (53%) by men (73%). Patients were usually exposed to Burkholderia pseudomallei during a holiday stay (58%) of less than 1 month (23%) and were hospitalized during the month following their return to Europe (58%). Among travelers, melioidosis is less often associated with risk factor (16%), diabetes being the most frequently comorbidity related (19%). The clinical presentation was multifaceted, pneumonia being the most common symptom (52%), followed by cardiovascular form (45%) and skin and soft tissues damages (35%). The diagnosis was obtained by culture (92%), often supplemented by morphological, biochemical, and molecular identification (23%). Misdiagnoses were common (21%). Over half of the patients received a complete and adapted treatment (56%). Mortality is lower for returning traveler (6%). Imported melioidosis cases into Europe have their own characteristics. This possibility should be considered in patients with pneumonia, fever, and/or abscess returning from endemic areas even years after.

Melioidosis in Sri Lanka

Until recently, Sri Lanka was not considered a country with endemic melioidosis. However, an increasing number of cases is being reported. National surveillance for melioidosis was instituted after 2008. A total of 250 culture-positive cases was recorded between 2006 and May 2017. Males predominated (71.6%). The age range was wide (2⁻92 years) reflecting a ubiquity of exposure. The majority (201/250, 80%) lived in rural areas. All provinces were affected. Case load increased during the two monsoonal periods (67%). There was representation of every population group including farmers (n = 44), housewives (n = 24), school children (n = 10), professionals (n = 5), businesspersons (n = 6), white-collar workers (n = 10) and blue-collar workers (n = 8). Diabetes was the predominant risk factor (n = 163, 65.2%). Clinical presentations included community-acquired sepsis and pneumonia, superficial and deep abscesses, and septic arthritis. Mortality was 20.4% (51/250). A majority (n = 212) of isolates belonged to the YLF (Yersinia-like fimbrial) clade but 38 were BTFC (B. thailandensis-like flagellum and chemotaxis). A total of 108 isolates was genotyped and 46 sequence types (STs) were identified, 40 being novel. It is clear that melioidosis is endemic in Sri Lanka with a wide geographic and demographic distribution. There is an urgent need to extend surveillance of melioidosis to under-resourced parts of the country and to populations at high risk.

Melioidosis in Travelers: Review of the Literature

BACKGROUND

Melioidosis is a bacterial infection endemic essentially in Southeast Asia and northern Australia. In temperate areas, the infection is extremely rare and is almost always imported by travelers or immigrants. The infection may affect almost any organ in the body, with various degrees of severity.

METHODS

We reviewed the literature on melioidosis in travelers. For this purpose we searched PubMed and Google for relevant articles up to July 2015.

RESULTS

We have identified 72 cases of melioidosis in travelers published in the literature. Melioidosis in travelers was acquired mostly in Thailand (46% of cases). The mean duration of stay in the endemic area was 36 days (range 7-330 days). Symptoms usually started at 23 days (range 1-360 days) after leaving the endemic area. The clinical presentation was varied, sepsis being the most common (34%) followed by pneumonia (29%) and abscess formation (25%). Melioidosis in travelers was less often associated with predisposing risk factors (37.5%), diabetes mellitus being the most common (21%), and had lower mortality (17%) than had the infection in autochthonous cases in Southeast Asia.

CONCLUSIONS

Melioidosis in travelers has its own characteristics, which distinguish it from other autochthonous diseases in indigenous populations. The possibility of melioidosis should be considered not only in patients originating from endemic areas, but also in patients returning from travel in those regions.

A case of melioidosis probably acquired by inhalation of dusts during a helicopter flight in a healthy traveler returning from Singapore

We present a case of melioidosis in an Italian male returning from Singapore after a short travel. He probably acquired the disease by inhalation, which is not the typical mode of transmission, in the absence of evident risk factors. The diagnosis was confirmed by real-time polymerase chain reaction of the culture while serology was useful to assess professional exposure among laboratory workers. Treatment consisted of an initial intensive phase with meropenem and trimethoprim-sulfamethaxazole (TMP-SMX), followed by 6 months of eradication therapy with TMP-SMX.

Neurological melioidosis in Norway presenting with a cerebral abscess

Neurological melioidosis is a rare condition, as less than 30 cases have been reported in the last 50 years. We present a case of neurological melioidosis, presenting with a cerebral abscess in a returning traveler from an endemic area. While traveling in Cambodia on holiday, the patient was admitted to local hospital for pneumonia. Her condition improved after antimicrobial treatment, and she returned to Norway when discharged. The patient had several contacts with the health care system after returning to Norway, due to recurrent fever and deterioration. Short-term antimicrobial treatment was given with temporary improvement in her condition. Eventually she developed stroke-like symptoms, and a cerebral abscess was found. Cultures from the abscess were positive for Burkholderia pseudomallei and the treatment was adjusted accordingly.

A multiplex nested PCR for the simultaneous detection of Salmonella typhi, Mycobacterium tuberculosis, and Burkholderia pseudomallei in patients with pyrexia of unknown origin (PUO) in Vellore, South India

BACKGROUND AND OBJECTIVES

Salmonella typhi, Mycobacterium tuberculosis, and Burkholderia pseudomallei are among the most important monocyte-tropic bacterial agents causing pyrexia of unknown origin (PUO), with a significant number of endemic infections in both South and Southeast Asian regions. These infections pose a major risk to travelers to these regions as well.

METHODS

We developed and evaluated a multiplex nested polymerase chain reaction (PCR) for the simultaneous detection of the three pathogens in 305 patients' buffy coat samples.

RESULTS

The assay for S. typhi and B. pseudomallei was able to detect down to 1 colony forming unit/5 μL PCR input and M. tuberculosis was detected down to 20 genome copies/5 μL PCR input. S. typhi was detected in 10 (3.3 %) individuals, B. pseudomallei in 10 individuals (3.3 %), and M. tuberculosis in 18 individuals (5.9 %). Co-infections of M. tuberculosis and B. pseudomallei were detected in three individuals and S. typhi and B. pseudomallei in two individuals.

CONCLUSION

This protocol is efficient for PUO diagnosis especially in Asian countries.