A cluster of Listeria monocytogenes infections in hospitalized adults.
BACKGROUND
Listeriosis occurs mainly in persons at extremes of age and with immunocompromising conditions. It is believed that most cases of listeriosis are acquired in the community. A cluster of listeriosis in hospitalized patients prompted the present investigation.


METHODS
We conducted a case series study of listeriosis from August 21, 2006, to June 1, 2007, in a hospital in the city of Rio de Janeiro, Brazil.


RESULTS
Six patients with Listeria monocytogenes infection were identified: 5 during hospitalization and 1 at a day clinic. By the time the infection was diagnosed, 5 patients had been in the hospital for a mean of 9 days. All patients were elderly (median age, 80 years) and had immunocompromising conditions. Five (83%) patients died. Four patients developed bloodstream infections, 3 caused by serotype 1/2b. Two patients had peritonitis: one caused by serotype 3b and another by serotype 1/2b. Four L monocytogenes isolates belonged to a single pulse-field gel electrophoresis genotype, suggesting a common source. An epidemiologic investigation pointed to the hospital kitchen as the possible contamination.


CONCLUSIONS
Data suggest a health care-associated outbreak of listeriosis and highlight the importance of developing guidelines for prevention and treatment of health care-associated foodborne diseases, especially in hospitals with immunocompromised adult patients.
Martins
Ianick Souto
IS
Faculdade de Medicina, Universidade Federal Fluminense, Niterói, Brazil. ianicksm@yahoo.com.br
Faria
Flavia Cristina da Conceição
FC
Miguel
Marco Antônio Lemos
MA
Dias
Manuela Pereira de Sá Colaço
MP
Cardoso
Fernando Luís Lopes
FL
Magalhães
Ana Cristina de Gouveia
AC
Mascarenhas
Luiz Affonso
LA
Nouér
Simone Aranha
SA
Barbosa
André Victor
AV
Vallim
Deyse Christina
DC
Hofer
Ernesto
E
Rabello
Renata Fernandes
RF
Rebello
Renata Fernandes
RF
Riley
Lee W
LW
Moreira
Beatriz Meurer
BM
D000368:Aged; D000369:Aged, 80 and over; D016470:Bacteremia / Q000453:epidemiology / Q000382:microbiology; D015373:Bacterial Typing Techniques; D001938:Brazil; D003428:Cross Infection / Q000453:epidemiology* / Q000401:mortality; D016172:DNA Fingerprinting; D004196:Disease Outbreaks; D016521:Electrophoresis, Gel, Pulsed-Field; D005260:Female; D005838:Genotype; D006760:Hospitalization; D006801:Humans; D016867:Immunocompromised Host; D008089:Listeria monocytogenes / Q000145:classification* / Q000302:isolation & purification*; D008088:Listeriosis / Q000453:epidemiology* / Q000401:mortality; D008297:Male; D008875:Middle Aged; D017720:Molecular Epidemiology; D010538:Peritonitis / Q000453:epidemiology / Q000382:microbiology; D012703:Serotyping