[Surveillance of nosocomial infection at a regional++ hospital. Results of incidence and prevalence studies in a 2 years' experience].
BACKGROUND
The most appropriate methods for surveillance of nosocomial infection (NI) in hospitals with less than 250 beds remain to be elucidated. The aims of this study were to investigate the differences between the results found in a study in incidence (IS) and in another concerning prevalence (PS) carried out in a county hospital and study the experience in the application of a collection method of incidental cases through a survey.


METHODS
For 2 years IS trimestrally accumulated and simultaneously PS trimestrally were applied for global surveillance and for type of NI as well as for knowing the etiology of the same. In both types of study all the hospital patients were included.


RESULTS
The accumulated incidence of patients with NI over the 2 years was 3.9% (3.6 in the first 12 months and 4.1 in the 12 remaining months) and the global prevalence was 7.5%. The global trend of NI was that of an increase in both studies. The most frequent NI in both studies were surgical wound and urinary infection. PS did not detect the least frequent NI. The etiologic agents of NI were similar in both studies. The survey undertaken for the detection of NI demonstrated 61% sensitivity, 98% specificity and a positive prediction value of 94%.


CONCLUSIONS
In small hospitals global prevalence studies may be useful for surveillance of the most frequent nosocomial infections. The results obtained by incidence studies were less variable and better reflect the trend of nosocomial infection. A survey used as a study method of incidence for the collection of cases of nosocomial infection loses sensitivity over time.
Javaloyas
M
M
Hospital de Viladecans, Barcelona.
García
D
D
Casasín
T
T
Colomer
J
J
Bonfill
X
X
Brotons
C
C
Rué
M
M
D015331:Cohort Studies; D003428:Cross Infection / Q000453:epidemiology*; D003430:Cross-Sectional Studies; D006761:Hospitals; D006801:Humans; D013030:Spain