Dados do Trabalho

Title

THE SEROCONVERSION RATE OF THE YELLOW FEVER VACCINE IS LOWER IN PATIENTS VACCINATED INADVERTENTLY

Background

The yellow fever vaccine contains a live attenuated virus of high immunogenicity and offers prolonged protection against yellow fever and it is generally safe in immunocompetent patients. However, in individuals with rheumatic diseases, it is necessary to evaluate the patient, avoiding vaccinations inadvertently. In addition, drug use and disease’s activities may influence in vaccine’s seroconversion.

Materials and methods

Retrospective observational study evaluating 37 patients after 30 days of vaccination, being the diagnoses: Rheumatoid Arthritis (RA) (n=15), Sjögren’s Syndrome (SS) (n=10), Ankylosing Spondylitis (AS) (n=8), Systemic Lupus Erythematosous (SLE) (n=1), Still Disease (SD)(n=1), Mixed Connective Tissue Disease (MCTD) (n=01) and Systemic Vasculitis (SV) (n=01). Viremia (CRP) and plaque reduction neutralization test (PRNT) were measured in D28 after vaccine. Adverse events were registered and adequate statistical analysis was performed. All tests considering a significant p-value <0.05. The PRNT was expressed in GeoMean title.

Results

18 of the evaluated patients were vaccinated inadvertently (48.6%), of which 13 (72.2%) were on immunobiological use [(Infliximabe (6), Adalimumabe (1), Abatacepte (2), Tocilizumabe (4)] and 5 (27.7%) on DMARDs use. There were no AE related in the inadvertent group. In the warned group (n = 19; 51.4%), 4 were on immunobiological use and only 5 were on DMARDs use. Myalgia and fatigue (SS without medication), myalgia (RA using methotrexate 7.5 mg / week), and arthralgia and skin rash (SS using prednisone 5 mg / day) were observed in this group. A patient with RA using methotrexate 15 mg / week and leflunomide 20 mg / day was diagnosed with endocarditis after 4 weeks of vaccination, but she already had mitral stenosis and we can not assign this event to the vaccine. The laboratory analysis was performed in 27 patients, 10 inadvertent and 17 warned, diagnosed with RA (n = 7, 2 warned and 5 inadvertent), SS (n = 9, all warned), spondylarteritis (n = 6, 3 warned and 3 inadvertent), Lupus (n = 1; Still's disease (n = 1, inadvertent), MCTD (n = 1, warned) and Takayasu's arteritis (n = 1, inadvertent). Seropositivity was significantly lower in the inadvertent group compared to warned group (64% vs. 94%, p = 0.03). The PRNT title in D28 was 247 warned and 91 inadvertent, p = 0.08.

Conclusions

No serious adverse events have been observed even in patients who have been vaccinated inadvertently. The seroconversion rate was lower in the group of inadvertently vaccinated, emphasizing the importance of medical guidance.