Vacinação em situações especiais / Vaccination in special situations

OBJETIVOS: Revisar a indicação, contra-indicação e eficácia da vacinação em algumas situações especiais: imunossupressão, prematuridade, gestação e pós-exposição. FONTES DOS DADOS: Revisão sistemática dos artigos sobre o tema publicado nas 2 últimas décadas pesquisados nas bases de dados MEDLINE, SciELO e Lilacs. Consulta às normas do Programa Nacional de Imunização, Brasil, 2001 a 2004, e normas do Programa Nacional de DST/AIDS, Brasil, 2004. Consulta aos temas livres publicados em anais de congressos internacionais e nacionais de pediatria e doenças infecciosas, nos últimos 5 anos. SíNTESE DOS DADOS: Algumas situações especiais, como imunossupressão, prematuridade, gestação e exposição às doenças infecciosas, colocam os indivíduos em maior risco de adoecer ou apresentar eventos adversos pós-vacinais. Essas situações requerem esquemas vacinais diferenciados, podem indicar adiamento da vacinação e mesmo contra-indicá-la. De modo geral, as vacinas inativadas, ou de toxóides, podem ser aplicadas, levando-se sempre em consideração a possibilidade de resposta imunogênica insuficiente. Para indivíduos imunossuprimidos, as vacinas de vírus e bactérias vivos devem ser evitadas devido ao risco de disseminação do agente vacinal. O cuidado na imunização deve incluir não só o paciente, mas seus contatos no domicílio, creche, etc. CONCLUSÕES: Esquemas adequados para cada uma dessas situações aumentam a possibilidade de obter melhor proteção vacinal e diminuem o risco de eventos adversos indesejáveis. Após exposição às doenças infecciosas, indivíduos imunodeficientes ou imunossuprimidos que não tiveram os títulos de anticorpos pós-vacinais avaliados devem ser considerados não protegidos, e medidas profiláticas disponíveis, incluindo imunização passiva, devem ser aplicadas, mesmo para aqueles previamente vacinados.

Vaccination in special situations.

OBJECTIVE: To review the indications, contraindications and efficacy of vaccination in some special situations: immunosuppression, prematurity, pregnancy and post-exposure situations. SOURCES OF DATA: Systematic review of articles published during the two last decades, found in MEDLINE, SciELO and Lilacs databases; guidelines of Programa Nacional de Imunizações (Brazilian National Immunization Program), 2001 to 2004, and of Programa Nacional de DST/AIDS (Brazilian National STD/AIDS Program), 2004. Abstracts published in national and international pediatric and infectious disease congress annals during the last five years were also consulted. SUMMARY OF THE FINDINGS: Some special situations, such as immunosuppression, prematurity, pregnancy and exposure to infectious diseases increased the risk of diseases or adverse post-vaccination events. In these situations, special vaccines or special vaccination schedules are indicated, or vaccines should be postponed or even forbidden. In general, toxoid or inactivated vaccines can be used, considering the possibility of insufficient immune response. For immunosuppressed patients, in accordance with the type of immunosuppression, live virus or bacterial vaccines should be avoided, because of the risk of vaccine agent spread. Immunization should include not only the patient, but his/her home and day-care contacts as well. CONCLUSIONS: Knowledge about the schedule indicated for each situation improves the chances of better vaccine protection and decreases the risk of adverse events. Immunosuppressed or immunodeficient patients whose post-vaccine antibody titers are not available should be considered susceptible when exposed to infectious disease, and all the available prophylactic measures should be implemented, even when the vaccination schedule is correct.

C-reactive protein follow-up of children with acute bacterial meningitis

Twenty-two children with bacterial meningitis were prospectively studied to follow serum levels of C-reactive protein (CRP) at admission, and the 2nd, 5th and 7th days of treatment, and in the cerebrospinal fluid (CSF) at admission, to investigate whether there is any relationship of its levels with the clinical evolution. CRP was measured by latex agglutination and/or ELISA techniques with detection limits of 0.15mg/L and 0.9mg/L, respectively. Patients were classified according to clinical evolution in two groups: uneventful recovery (n=12) and complicated evolution (n=10). Clinical complications observed were: relapse of fever (8), persistent fever (4), arthritis (4), ventricle enlargement (2), subdural effusion (1), subdural empyema (1), ataxia (1), cervical hypotonia (1), deafness (1), endophthalmitis (1), accute otitis media (1), secondary skin infection (1) and treatment change due to poor clinical response (1). A significant decrease in CRP levels was observed among the uneventful recovery group after admission. In contrast, in the group with complicated evolution, CRP levels showed either secondary elevation or remained high continously. Mean serum CRP levels were significantly lower in the uneventful recovery group than in the complicated evolution group on the 5th and 7th days. CRP levels below 20mg/L on the 5th and 7th days were associated with an uneventful recovery, and CRP levels higher than 20mg/L on those same days were associated with a complicated clinical evolution (p=0.01* and p=0.0015*, respectively). We conclude that serumm CRP level monitoring in children with bacterial meningitis provides useful and objective information about their clinical evolution. This procedure is inexpensive and suitable for use in endemic areas lacking sophisticated laboratories.