Pôster:

Baggio-Yoshinari syndrome (BYS) or Brazilian Lyme Symile Disease (BLSD) is a rare infectious disease that was described in Brazil in 1992. It is caused by different species of the Borrelia burgdorferi sensu Lato complex, which is transmitted through ticks of the species Amblyomma cajanense, better known as star ticks. Among the main reservoirs of these vectors are capybaras and horses. The disease is characterized by skin manifestations, typically migratory erythema, articular, neurological, ophthalmological, cardiac and psychiatric. Several of these manifestations can be chronified, lasting months or years. The diagnosis is essentially clinical. It is important to consider compatible epidemiology and the possibility of positive serological research for B. burgdorferi. Treatment will depend on the stage and type of manifestation of the disease. Primary infection is preferably treated with doxycycline for thirty days.

Case report

A 5-year-old child, previously healthy with a history of contact with ticks. He starts with prolonged fever, and progresses with asymmetrical and additive polyarthritis and widespread erythemato-pustular lesions. Treatment with non-hormonal anti-inflammatory drugs and prednisone was attempted. Subsequently, cephalexin and azithromycin were used, but without clinical response. Research for arboviruses and viral infections was negative. Rheumatological tests were negative. The child presented visual acuity alterations and the ophthalmological evaluation detected the presence of vitreitis and focal retinitis. Diagnosis was made after five months of disease progression, through serological research for Lyme-simile with positive IgM. During this time, the child's twin brother, who has also contacted ticks, developed the same symptoms and was confirmed with positive serology for BYS disease. Both were treated with doxycycline for 30 days and prednisolone with improvement of fever and skin lesions. However, four months after the end of treatment, the children persisted with polyarthritis, when methotrexate was initiated for both due to chronic arthritis.

Conclusion

Despite the high incidence of the star tick in our country, BYS is rare and challenging for physicians, mainly due to the enormous variety of presentation forms. In that case, what led us to insist on the investigation of infectious disease was the fact that the two brothers developed the same condition at the same time and both were bitten by ticks shortly before the development of clinical manifestations. Treatment has been a challenge. The systemic and ophthalmological manifestations were solved with antibiotic therapy, but the articular and cutaneous manifestations, have not yet presented remission.