Imported loiasis: Diagnostic and therapeutic challenges

• Loiasis is a neglected tropical disease that can be imported into non-endemic regions. • Loiasis should be suspected in patients returning from Central Africa who present with variable clinical signs and eosinophilia. • The biological diagnosis of loiasis is limited by the imperfection of serological and microscopic diagnostic tools. • Loa loa treatment must be adapted using a precise decision-making algorithm to prevent severe adverse effects. Loiasis is a vector-borne parasitic disease that has long been neglected due to its benign nature and its geographical distribution, which is restricted to the forest regions of Central and West Africa. However, it is now recognized as a significant public health concern in endemic areas, where chronically infected patients face organ damage and an increased risk of mortality. Loiasis presents several challenges, from diagnosis to treatment, as inappropriate therapies can lead to severe and at times fatal side effects. Although loiasis has low prevalence in Europe, historical connections with most endemic countries expose the continent to a high risk of imported cases, making it the most commonly imported filariasis in Europe. Population movements challenge healthcare providers, who often struggle with limited diagnostic and therapeutic tools. It is therefore essential to adopt an appropriate approach aimed at optimizing to optimize patient management and preventing severe adverse effects due to inappropriate treatment. At present, however, there exist no specific recommendations for managing imported loiasis. The present review aims to evaluate the current state of knowledge on its management and to propose an optimal approach through a decision-making algorithm, emphasizing pathophysiology by patient category, biological diagnostic methods and perspectives, as well as therapeutic strategies adapted to the challenges of non-endemic areas. These updated data aim to help clinicians from non-endemic areas to improve management of imported loiasis through development of a decision-making algorithm.