BackgroundAcute invasive fungal infections of the head and neck secondary to tyrosine kinase inhibitors are rare and potentially life-threatening events.Case presentationWe report a case of mucormycosis of the thyroid gland in a patient known for chronic lymphocytic leukemia receiving ibrutinib who presented with a rapidly growing thyroid nodule and dysphonia. An acute invasive fungal infection was identified on a core needle biopsy; mucormycosis was confirmed on culture. The patient was successfully treated with surgical debridement and long-term antifungal therapy.ConclusionPatients on ibrutinib may be at risk of acute invasive fungal infections of the head and neck.

Purpose of review Traveller's diarrhea, though not life-threatening. is often a vexing problem, which impacts overall function of the traveller while on holiday. Increasing data is available regarding molecular diagnostic techniques, which may help obtain an early etiologic diagnosis. Use of antibiotics for traveller's diarrhea is controversial in this era of multidrug resistance and microbiome disruption. Recent findings Travel to the tropics promotes gut colonization with drug-resistant bacteria and this risk increases after treatment with antibiotics, leading to potential ecological impacts in the country of residence. Summary Traveller's diarrhea is common and can impact a traveller's itinerary leading to significant inconvenience, and occasional longer term sequelae. Though bacterial causes predominate, recommended treatment is conservative in mild-to-moderate cases. Molecular techniques for early diagnosis of traveller's diarrhea may help with appropriate management. Treatment with antibiotics is sometimes required but is associated with gut colonization by multidrug-resistant bacteria.

Cell cytotoxicity neutralization assay (CCNA) is considered to be a gold standard to diagnose Clostridioides difficile infections. We performed CCNA on 77 consecutive admission screening rectal swabs from asymptomatic toxigenic C. difficile carriers. Thirty-nine percent of specimens from asymptomatic carriers were positive. Thus, CCNA specificity may be lower than previously thought.