1 - Unidade de Infecciologia, Hospital Dona Estefânia, Centro Hospitalar Universitário de Lisboa Central
2 - Serviço de Patologia Clínica, Hospital Dona Estefânia, Centro Hospitalar Universitário de Lisboa Central
3 - Departamento de Doenças Infeciosas, Instituto Nacional de Saúde Doutor Ricardo Jorge
- Publicação como Carta ao Editor na Portuguese Journal of Pediatrics 2021;52:250-1 DOI: https://doi.org/10.25754/pjp.2021.21633
Resumo: Neisseria meningitidis is a common cause of bacterial meningitis and early treatment is mandatory for better outcome. In order to prevent secondary cases, chemoprophylaxis is indicated in close contacts. In Portugal, as in many European countries, rifampicin is the first-line drug recommended for prophylaxis. The mechanism of the resistance is linked to point mutations in the rpoB gene. We present the first case of rifampicin-resistant Neisseria meningitidis serotype B in Portugal. In February of 2018, an eight-month-old infant previously healthy was hospitalized with fever, vomiting and petechiae. Evolution to sepsis with hemodynamic instability and disseminated intravascular coagulation occurred. Meningococcemia was suspected and she was started on ceftriaxone 100mg/kg/dosage once daily. No cerebrospinal fluid was collected and blood cultures were negative. Prophylaxis with rifampicin was prescribed for close contacts and the Health Delegate was notified. Four days after the hospitalization of the index-case and one day after a course of prophylactic rifampicin, fever and vomiting developed in the index-case‘s three-year-old sister. Lumbar puncture was performed and blood cultures were obtained and she was started on ceftriaxone 100mg/kg/dosage once daily. Cerebrospinal fluid cultures were positive for Neisseria meningitidis ceftriaxone-sensitive (ETest, MIC:0.016μg/ml)7, with intermediate sensitivity (susceptible, increased exposure according to the new definition) to penicillin (ETest, MIC:0.25μg/ml)7 and resistant to rifampicin (ETest, MIC >32μg/ml)7. Serotyping identified Neisseria meningitidis serotype B. Household contacts again received chemoprophylaxis, this time with ciprofloxacin (children and pregnant contacts received prophylaxis with ceftriaxone). The genotype analysis didn’t show any mutation in the rpoB gene that would be linked to the rifampicin resistance, so there must be an unknown mechanism of resistance. The evolution was favorable, without acute sequelae. Complement study was normal in both cases. The aim of this letter is to raise concern about rifampicin-resistant Neisseria meningitidis and its implications for chemoprophylaxis. Although this resistance seems to remain a rare event, since it is a severe disease it is very important to monitor changes in the level of antibiotic susceptibility among clinical isolates.
Palavras Chave: Profilaxia, Meningite, Resistência, Rifampicina