Trends in Infectious Diseases: A Retrospective 5-year Study

Background: Although hospital admission is frequently due to the exacerbation of chronic diseases, most often it is caused by an underlying infectious process. Patients often have several admissions per year, making them at risk for recurrent infections, increased morbidity, and the emergence of resistant strains of microorganisms. Methods: This is a retrospective, descriptive study of all patients with an infectious disease diagnosis, who were admitted to the medical ward of a tertiary hospital during a 5-year period. Information was collected from electronic medical files regarding gender, age, autonomy, comorbidities, primary diagnosis, in-hospital length of stay, and mortality as well as microbiological data surveillance. Results: A total of 355 patients fulfilled the inclusion criteria. Amongst the sample analysed, the average age was 78.10±12.47 years. Of the patients, 57.2% (203) were female, with most patients considered as dependent according to Katz score. The average Charlson Comorbidity Index (CCI) score was 6.28±2.74, increasing with age. The main diagnostic categories were respiratory (191 patients: 137 with pneumonia and 49 with acute bronchitis) and urinary tract (138 patients: 69 with pyelonephritis and 66 with cystitis). Urinary tract infections were more frequent in females and in dependent patients. Only 37.8% of infections had a microbiologic isolate: Escherichia coli (28.4%), Pseudomonas aeruginosa (12.7%), and Klebsiella pneumoniae (8.2%). The overall mortality was 6.77%. Conclusions: The frequent in-hospital admission due to infectious diseases makes it imperative to characterise and follow-up on evolution of the disease itself in order to better know the characteristics of community-acquired diseases, establish routes of transmission and outbreak identification, microbiology patterns, and resistance towards further improving empiric therapy.