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Summary Background Cutaneous larva migrans (CLM), a zoonotic helminthiasis imported to Canada by travelers to the tropics, causes morbidity due to severe, intractable pruritus. Treatment in Canada is only available through the Special Access Program (SAP) of Health Canada, thus, many patients are prescribed ineffective courses of non-targeted therapy. Objective We analyzed patients with CLM referred to our specialized Tropical Disease Unit (TDU) having failed non-targeted therapy prior to referral, and characterized demographic and travel related correlates of CLM. Methods Patients with CLM evaluated between June 2012 and December 2014 were identified through our SAP application log, and charts were reviewed for demographic, clinical, and travel-related data following IRB approval. Results 25 patients with CLM were identified: 12 women, and 13 men. Median age was 35 years (range 4–58 years). Patients had primarily acquired their CLM in the Caribbean (80%), with Jamaica being the most well represented source destination (N = 10, 40%). Reported symptoms included intense, function-limiting pruritus (N = 25, 100%) and loss of sleep (N = 3, 12%). Twelve patients (48%) with CLM had received at least 1 course of non-targeted therapy prior to referral. Non-targeted therapies included topical steroids (N = 7), cryotherapy (N = 3), oral antibiotics (N = 2), and oral mebendazole (N = 11). Median duration of symptoms was 34 days (range 5–226 days). Of 25 patients with CLM, 23 (92%) were prescribed a single 3-day course of albendazole and responded appropriately, and 2 (8%) required a second 3-day course of albendazole. Conclusions Although CLM is non-communicable and of little public health relevance in Canada, it causes significant morbidity. A substantial proportion of patients with CLM referred to our specialized TDU had a prolonged course of illness and were prescribed ineffective and non-targeted therapies. Oral albendazole or ivermectin, or topical thiabendazole, are the drugs of choice for CLM, and should be prescribed as first-line therapy.

Background We evaluated the performance of stool microscopy, serology, and real time PCR (qPCR) for the diagnosis of strongyloidiasis at our reference laboratory. Methods Using a convenience sample of specimens submitted between April 1, 2014 and May 31, 2015, positivity rates and performance characteristics were calculated. Results During the enrolment period, 17,933 stool specimens were examined for O&P, 14 of which were positive for Strongyloides larvae. For stool specimens serially positive for larvae, mean duration of larval shedding was 12.7 days following the initial positive specimen, while for sputum and urine, it was 12 and 2 days, respectively. During the enrolment period, 3258 specimens were processed for Strongyloides serology, 200 of which were reactive (6.1%), 210 indeterminate (6.5%), and 2848 non-reactive (87.4%). qPCR was positive in 11 of 12 (91.7%) stool specimens containing larvae, and negative in all stool specimens without larvae by microscopy. There was no cross-reactivity of Strongyloides-specific qPCR to other stool protozoa or helminths. Conclusions In the absence of immunosuppression, larval burden in strongyloidiasis is low, limiting the utility of microscopy, and favoring serologic testing. However, false negative serology can occur in those with hyperinfection necessitating a combined diagnostic approach. qPCR was insufficiently sensitive to replace microscopy for detection of larvae.