Neopterin and CXCL-10 in Cerebrospinal Fluid as Potential Biomarkers of Neuroinvasive Dengue and Chikungunya.

Dengue (DENV) and chikungunya viruses (CHIKV) cause severe neurological complications, sometimes undiagnosed. Therefore, the use of more accessible neuroinflammatory biomarkers can be advantageous considering their diagnostic and prognostic potential for aggravated clinical outcomes. In this study, we aimed to evaluate neopterin and C-X-C motif chemokine ligand 10 (CXCL-10) in cerebrospinal fluid (CSF) for the diagnosis of neuroinvasive DENV and CHIKV. We analyzed the CSF of 66 patients with neurological disorders, comprising 12 neuroinvasive DENV/CHIKV, 20 inflammatory control (viral, bacterial, and fungal meningitis, and autoimmune disorders), and 24 noninflammatory control (cerebrovascular disease, dementia, neoplasm). There was no difference between the concentration of CSF neopterin in the neuroinvasive DENV/CHIKV and control groups. However, there was a significant difference in the CXCL-10 level when comparing the neuroinvasive DENV/CHIKV group and the non-inflammatory control (p < 0.05). Furthermore, we found a linear correlation between neopterin and CXCL-10 CSF levels in the three groups. For the DENV/CHIKV neuroinvasive diagnosis, the ROC curve showed the best cut-off values for CSF neopterin at 11.23 nmol/L (sensitivity of 67% and specificity of 63%), and for CSF CXCL-10 at 156.5 pg/mL (91.7% sensitivity and specificity). These results show that CXCL-10 in CSF represents an accurate neuroinflammatory biomarker that may contribute to neuroinvasive DENV/CHIKV diagnosis.

Fatal Human Case of Zika and Chikungunya Virus Co-Infection with Prolonged Viremia and Viruria.

Zika virus (ZIKV) infection usually presents as a mild and self-limited illness, but it may be associated with severe outcomes. We describe a case of a 30-year-old man with systemic erythematous lupus and common variable immunodeficiency who became infected with both Zika (ZIKV) and Chikungunya (CHIKV) virus during the 2016 outbreak in Rio de Janeiro, Brazil. The patient presented with intense wrist and right ankle arthritis, and ZIKV RNA and virus particles were detected in synovial tissue, blood and urine, and CHIKV RNA in serum sample, at the time of the diagnosis. During the follow up, ZIKV RNA persisted for 275 days post symptoms onset. The patient evolved with severe arthralgia/arthritis and progressive deterioration of renal function. Fatal outcome occurred after 310 days post ZIKV and CHIKV co-infection onset. The results show the development of severe disease and fatal outcome of ZIKV infection in an immunosuppressed adult. The data suggests a correlation between immunodeficiency and prolonged ZIKV RNA shedding in both blood and urine with progressive disease. The results also indicate a possible role for arbovirus co-infections as risk factors for severe and fatal outcomes from ZIKV infection.

Zika virus shedding in human milk during lactation: an unlikely source of infection?

Zika virus (ZIKV) transmission through non-mosquito-dependent routes has become increasingly important since reports of sexual transmission. Breastfeeding is a potential means of ZIKV transmission, but data on this remain limited. The cases of four mothers with laboratory-proven infections are reported. No disease evolved in three of the breastfed babies despite detectable maternal viremia and viruria, the presence of viral RNA shedding, and the isolation of infective particles in one milk sample. Fever and rash in one infant of a ZIKV-infected mother proved to be related to chikungunya virus infection. The results suggest that the presence of infective particles in breast milk may not be sufficient for the efficient perinatal transmission of ZIKV.

Review of the etiologies of viral meningitis and encephalitis in a dengue endemic region.

OBJECTIVES: To evaluate the etiology of viral meningitis and encephalitis in adults and adolescents living in areas affected by dengue. METHODS: Over two years, adults and adolescents with diagnoses of viral encephalitis or meningitis were selected for study in Brazil. PCRs for dengue, enterovirus, HSV1 and 2 and cytomegalovirus were performed in CSF samples. Serum and CSF samples were tested for the presence of anti-dengue IgM antibodies. RESULTS: The etiologies of encephalitis and meningitis were determined in 70% of cases (30/47). Dengue was the leading cause of encephalitis (47%) with normal CSF cellularity in 75% of these patients. HSV1 was found in 17.6% of the cases, two of which had mild encephalitis. Enterovirus was the most common cause of meningitis (50%), followed by HSV1 (15%), cytomegalovirus and dengue (10%, each). CONCLUSIONS: We identified the viral agents causing encephalitis and meningitis in a higher proportion of cases than has been reported in other studies. Dengue was the most frequent cause of encephalitis, which surpassed HSV. In endemic areas, dengue should be investigated as an important cause of encephalitis. Normal CSF cellularity should not exclude dengue encephalitis. Enterovirus is known to be the leading cause of meningitis in children, but here we found it was also the main cause of the disease in adults. HSV1 should be investigated in patients with mild forms of encephalitis and meningitis.