Human alveolar echinococcosis (AE) is a zoonotic cestode infection which is usually fatal in the absence of treatment. Treatment involves major surgery or indefinite antiparasitic therapy. The incidence is rising in Europe and Asia, with an increased risk observed in immunocompromised individuals. Previously, AE acquisition in North America was extremely rare, except for one remote Alaskan Island. Recent studies have demonstrated a new European-like strain of Echinococcus multilocularis (Em) in wildlife and in human AE in western Canada. We report the experience of all AE patients diagnosed in Alberta. Each was diagnosed by histopathology, serology, and PCR-confirmed by a reference laboratory. Seventeen cases of human AE, aged 19–78 years, nine females, were diagnosed between 2013 and 2020: all definitely or probably acquired in Alberta. Six lived in urban areas, and 14 had kept dogs. In eight, the lesions were found incidentally on abdominal imaging performed for other indications. Six were immunocompromised to varying degrees. Six were first diagnosed at surgery. All have been recommended benzimidazole therapy. One died of surgical complications. Clinicians should be aware of this diagnostic possibility in patients presenting with focal nonmalignant hepatic mass lesions. Greater urbanization of coyotes, the predominant definitive host of Em in Alberta, and growing numbers of immune suppressed individuals in the human population may lead to increasing recognition of AE in North America.
Objectives.Approximately 65 percent of tuberculosis (TB) cases in Canada each year occur from reactivation in foreign-born individuals. Refugees are at high risk after immigration. Routine screening of this population for latent TB infection (LTBI) is generally considered infeasible. We evaluated the outcome of LTBI screening and treatment amongst refugees.Methods.Government-sponsored refugees in Edmonton are seen at the New Canadians’ Clinic and screened for TB and LTBI. We reviewed records of patients between 2009 and 2011. Completeness of initial assessment, diagnosis of latent infection, and completion of LTBI treatment were evaluated. Treatment for LTBI was offered when patients had a positive Tuberculin Skin Test (TST) and risk factors for progression to TB. An Interferon-Gamma Release Assay (IGRA) was performed on all other TST positives; treatment is only offered if it was positive.Results.949 refugees were evaluated. 746 TSTs were read, with 265 positive individuals. IGRA testing was performed in 203 TST positive individuals without other TB risk factors; 110 were positive. LTBI treatment was offered to 147 of 151 eligible patients, 141 accepted, and 103 completed a treatment course.Conclusion.We observed high proportions of patient retention, completion of investigations, and treatment. This care model promises to be a component of effective TB prevention in this high-risk population.
8 March 2024 in The Journal of Infectious Diseases
Epidemiologic research on zoonotic tuberculosis historically used Mycobacterium bovis as a surrogate measure; however, increased reports of human tuberculosis caused by other animal-associated Mycobacterium tuberculosis complex members like Mycobacterium orygis necessitates their inclusion. We performed a retrospective cohort study including persons infected with any animal-lineage M tuberculosis complex species in Alberta, Canada, from January 1995 to July 2021, identifying 42 patients (20 M bovis, 21 M orygis, 1 M caprae). Demographic, epidemiologic, and clinical characteristics were compared against persons with culture-confirmed M tuberculosis infection. The proportion of culture-positive infections caused by M orygis increased continuously from 2016 to 2020. Significantly more females at a higher median age were impacted by M orygis, with all patients originating from South Asia. Mycobacterium bovis caused significantly more extrapulmonary disease and disproportionately impacted young females, particularly those pregnant or postpartum. All infections were acquired abroad. These findings can aid in developing targeted public health interventions.
1 February 2018 in Canadian Journal of Public Health
The management of tuberculosis (TB) in people with medical co-morbidities, substance-use disorders, advanced age or pregnancy is challenging; consultation with a TB expert is recommended.Adverse ev...