Behavioral and recreational risk factors for free-living amebic infections

Acanthamoeba encephalitis in immunocompetent hosts: A report of two cases

Acanthamoeba are ubiquitous free-living amoeba. Acanthamoeba infections cause necrotizing vasculitis, resulting in vessel thrombosis and cerebral infarction. Acanthamoeba CNS infections, though uncommon, are associated with high mortality. Diagnosis is difficult and often delayed. Here, we present two immunocompetent hosts with Acanthamoeba encephalitis with good outcomes.

The Disease Ecology, Epidemiology, Clinical Manifestations, and Management of Emerging Cryptococcus gattii Complex Infections

Cryptococcus neoformans, a soil-dwelling fungus found worldwide, can cause cryptococcosis, an opportunistic fungal infection of the lungs and central nervous system. One former member of the C neoformans complex, Cryptococcus gattii, has caused meningitis in immunosuppressed and immunocompetent persons in endemic regions in Africa and Asia. Between 1999 and 2004, C gattii caused outbreaks of human cryptococcosis in unexpected, nonendemic, nontropical regions on Vancouver Island, Canada, and throughout the US Pacific Northwest and California. C gattii was recognized as an emerging species with several genotypes and a unique environmental relationship with trees that are often encountered in the wilderness and in landscaped parks. Because C gattii infections have a high case-fatality rate, wilderness medicine clinicians should be aware of this emerging pathogen, its disease ecology and risk factors, its expanding geographic distribution in North America, and its ability to cause fatal disease in both immunosuppressed and immunocompetent persons.

Amoebic Encephalitis Caused by Balamuthia mandrillaris

We present the case of a 71-year-old man who was diagnosed with amoebic encephalitis caused by Balamuthiamandrillaris. He had rheumatic arthritis for 30 years and had undergone continuous treatment with immunosuppressants. First, he complained of partial spasm from the left thigh to the left upper limb. Magnetic resonance imaging revealed multifocal enhancing nodules in the cortical and subcortical area of both cerebral hemispheres, which were suggestive of brain metastases. However, the patient developed fever with stuporous mentality and an open biopsy was performed immediately. Microscopically, numerous amoebic trophozoites, measuring 20 to 25 µm in size, with nuclei containing one to four nucleoli and some scattered cysts having a double-layered wall were noted in the background of hemorrhagic necrosis. Based on the microscopic findings, amoebic encephalitis caused by Balamuthiamandrillaris was diagnosed. The patient died on the 10th day after being admitted at the hospital. The diagnosis of amoebic encephalitis in the early stage is difficult for clinicians. Moreover, most cases undergo rapid deterioration, resulting in fatal consequences. In this report, we present the first case of B. mandrillaris amoebic encephalitis with fatal progression in a Korean patient.

Illnesses Associated with Freshwater Recreation During International Travel

PURPOSE OF REVIEW

International travel, adventure travel, and eco-tourism are increasing over the past few decades. This review aims to summarize the spectrum of infections associated with recreational freshwater activities and international travel.

RECENT FINDINGS

Recreational water activities can be associated with a wide range of infections. Acute febrile illnesses due to leptospirosis and schistosomiasis are not uncommon in travelers following extensive freshwater exposure. Aeromonas and other water-associated pathogens are important to consider in a traveler presenting with a skin and soft tissue infection. Recreational water activities are often associated with diarrheal illnesses, especially in children, and the range of enteric pathogens includes bacterial pathogens such as Escherichia coli O157:H7 and Shigella species and the protozoan parasites Cryptosporidium and Giardia duodenalis. Infections due to free-living amebas though rare can lead to fulminant central nervous system infections. A diverse range of infections may be associated with freshwater exposure, and it is important that these entities are considered in a returning traveler presenting with an acute illness.

Contact lens wearers' experiences while trekking in the Khumbu region/Nepal: a cross-sectional survey

BACKGROUND

Safe contact lens wear depends on a hygiene regime and lens-appropriate wear patterns which may be compromised during travel in remote and wilderness areas. The purpose of this study was to describe the experience of contact lens wearers while trekking at high-altitude in Nepal.

METHODS

For this descriptive study, trekkers with contact lenses were recruited in Lukla and invited to complete an online-questionnaire on trip preparation, contact lens use, care and experiences, and possible changes for future travel. Quantitative data were analysed using SurveyMonkey; content analysis applied to qualitative responses.

RESULTS

The majority of the 158 participants (124; 78.48%) reported no problems with their lenses (daily disposables, soft lenses, extended-wear lenses, hard/rigid lenses) during their stay although dry air, dust, wind, cold temperatures, and difficult hygiene maintenance were challenging. Freezing lenses and freezing solutions were additional challenges. Thirty-four (21.52%) experienced a variety of problems. Improvements were requested from manufacturers. Lodges should provide better access to clean water, mirrors and lighting. Almost 60% of participants had not sought any pre-travel health advice.

CONCLUSIONS

Remote and wilderness areas provide a challenge for appropriate contact lens wear and care. The decision between the potential risk of infection due to touching lenses (daily disposables, soft/hard lenses) and the potential risk of corneal erosion (extended-wear lenses) needs to be made in pre-travel consultations. Travel health professionals and travel agencies should remind CL-wearing trekkers to carefully assess their wear and care routine to accommodate potentially challenging conditions.