Possible Sub-type of Juvenile Onset Lupus Identified with Higher Risk of Nervous System Complications
Aquaporin-4 antibodies, or “AQP4-Ab”, have been identified across a spectrum of inflammatory disorders, including adult onset lupus. However, no studies have assessed the presence of these antibodies in children and teens with juvenile onset lupus. In a new study, researchers screened a large group of patients with juvenile lupus for AQP4-Ab, and then studied clinical and laboratory predictors of the presence of AQP4-Ab positivity in juvenile lupus.
Researchers tested the blood of 90 ethnically diverse people between the ages of 11 and 19 with juvenile onset lupus and screened for the presence of AQP4-Ab. They also tracked each person’s demographic information (like age and sex), clinical details (like symptoms and previous organ involvement), and lab values (like blood levels of other antibodies and proteins). Drug regimens were also recorded.
They found that, out of the 90 people screened, five tested positive for AQP4-Ab. Of these five people, four remained positive on follow-up tests. Four out of the five were also diagnosed with neuromyelitis optica spectrum disorders, inflammatory disorders of the central nervous system characterized by severe damage to the optic nerves and spinal cord.
These findings suggest that there is a subgroup of people with juvenile onset lupus that develops AQP4-Ab and is at an increased risk of neurological (nervous system and nerves) involvement in the course of their disease. The researchers recommend that all people with juvenile onset lupus should be screened for the presence of this antibody, since it may help identify a high risk for neurological complications.
“The strength of this study is that the researchers included a large number of juvenile onset lupus patients. The test is specific, meaning that a negative test always had a negative result. However, some patients with neurologic involvement also did not have the antibody, meaning it is not very sensitive. Therefore, further studies in larger cohorts will be needed to assess the prevalence of this antibody in juvenile onset lupus patients before we can really know if this antibody defines a new subset of patients. More research is needed to understand if Aquaporin-4 antibodies should be used as a screening test” shares study investigator, Laura Lewandowski, M.D.
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