Building a network for multicenter, prospective research of central nervous system infections in South America: Process and lessons learned.

Multicenter collaborative networks are essential for advancing research and improving clinical care for a variety of conditions. Research networks are particularly important for central nervous system infections, which remain difficult to study due to their sporadic occurrence and requirement for collection and testing of cerebrospinal fluid. Establishment of long-term research networks in resource-limited areas also facilitates diagnostic capacity building, surveillance for emerging pathogens, and provision of appropriate treatment where needed. We review our experience developing a research network for encephalitis among twelve hospitals in five Peruvian cities since 2009. We provide practical suggestions to aid other groups interested in advancing research on central nervous system infections in resource-limited areas.

Proviral load and immune markers associated with human T-lymphotropic virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) in Peru.

Human T-lymphotropic virus type 1 (HTLV-1) is the aetiological agent of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The objective of this study is to identify which ex vivo and in vivo markers are associated independently with HAM/TSP in a Peruvian population. Eighty-one subjects (33 men/48 women) were enrolled: 35 presented with HAM/TSP, 33 were asymptomatic HTLV-1 carriers (ACs) and 13 were HTLV-1-seronegative controls (SCs). Ex vivo markers included T cell proliferation and Th1 [interferon (IFN)-gamma], Th2 [interleukin (IL)-4, IL-5], proinflammatory [tumour necrosis factor (TNF)-alpha] and anti-inflammatory (IL-10) cytokine production in non-stimulated peripheral blood mononuclear cell (PBMC) cultures. In vivo CD4(+) T cell count, markers of Th1 [interferon-inducible protein (IP)-10] and Th2 (sCD30) activity in plasma and HTLV-1 proviral load in PBMCs were also evaluated. In univariate analysis, several markers, including T cell proliferation, IFN-gamma, IP-10, sCD30 and proviral load were associated with HAM/TSP, but in a multiple logistic regression analysis only the proviral load remained associated significantly with disease manifestation [adjusted OR 9.10 (1.24-66.91)]. Our findings suggest that HAM/TSP is associated primarily with proviral load, whereas the observed association with some immune markers seems secondary.