PORTSMOUTH/TIVERTON — If the Sakonnet River Bridge looks a little greener than usual Friday night, there’s a reason.

The bridge will be illuminated in green on Oct. 9 as part of a worldwide campaign to raise awareness of PANS and PANDAS, neuroimmune conditions that can cause the sudden onset or worsening of obsessive-compulsive symptoms, severe anxiety, tics and other neuropsychiatric symptoms.

Portsmouth’s bridge will be in some pretty prominent company.

More than 300 landmarks around the world are expected to glow green for World PANS/PANDAS Awareness Day as part of the third annual #LightUp4PANS campaign organized by the Alliance to Solve PANS & Immune-Related Encephalopathies (ASPIRE) and 17 international advocacy organizations.

The Sakonnet River Bridge is the only Rhode Island landmark listed by organizers for this year’s campaign.

Other participating sites include Niagara Falls, the Rock & Roll Hall of Fame in Cleveland, Philadelphia’s Lincoln Financial Field, the Nebraska State Capitol and bridges and public buildings across the country.

The green lights are intended to draw attention to conditions that advocates say remain poorly understood and can go unrecognized for long periods.

“Lighting landmarks green is about more than awareness,” ASPIRE President Gabriella True said. “It is about making PANS and PANDAS visible so that families are heard, healthcare providers recognize the signs, and patients have a better chance of getting the care they need.”

PANS stands for pediatric acute-onset neuropsychiatric syndrome, while PANDAS stands for pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections.

ASPIRE says greater awareness among families and healthcare providers can lead to earlier recognition and treatment.

For Portsmouth and Tiverton residents, however, Friday’s message will be hard to miss: One of the area’s biggest landmarks will be glowing green along with hundreds of others around the world.