ABSTRACT
Between January 1996 and May 1997, a four-fold increased rate of isolation of Serratia marcescens was observed amongst patients admitted to the surgical Intensive Care Unit (SICU) of the Leiden University Medical Center compared to the preceding years. Random amplification of polymorphic DNA showed the involvement of genotypically distinct strains, implicating multiple different sources. After improvement of hygienic measures the frequency of isolation of S. marcescens returned to baseline. A case-control study was performed to assess patient-related risk factors for acquisition of S. marcescens. Nineteen cases and 38 controls were included. Hospital- and SICU-stay were significantly longer in case patients than in controls. By univariate analysis, statistically significant differences were found in body weight, the duration of mechanical ventilatory support, the cumulative use of antimicrobial agents, the use of aminoglycosides, parenteral nutrition and tube feeding. The sum of the number of days per invasive device (deep intravenous lines, arterial lines, wound drains and urinary catheters) was higher in cases than in controls (P = 0.08). Categorically, a cumulative number of device-days > 25 was a statistically significant risk factor for acquisition of S. marcescens. Multivariable logistic regression analysis showed that body weight, parenteral feeding and mechanical ventilation were independent predictors of acquisition of S. marcescens. As transmission of S. marcescens appears to be by the hands of personnel, the identified risk factors may act by necessitating an increased frequency and intensity of direct contacts.
Subject(s)
Cross Infection/prevention & control , Infectious Disease Transmission, Professional-to-Patient , Serratia Infections/prevention & control , Serratia Infections/transmission , Serratia marcescens/isolation & purification , APACHE , Case-Control Studies , Disease Outbreaks , Female , Genotype , Humans , Intensive Care Units , Length of Stay , Male , Middle Aged , Netherlands , Polymerase Chain Reaction , Regression Analysis , Risk Factors , Serratia marcescens/classification , Serratia marcescens/genetics , Surgical Wound Infection/prevention & control , Surgical Wound Infection/transmissionABSTRACT
In an epidemic of prosthetic valve endocarditis caused by Staphylococcus epidermidis the surgeon was found to be the source of contamination. The probable route was accidental puncture of gloves during operation. During the epidemiological investigation a second cluster of patients contaminated with Staph epidermidis during open heart surgery was found also related to one surgeon. This strain caused no detectable signs or symptoms of infection. Carriage of virulent staph epidermidis has rarely been recognised as a hazard but may have serious consequences.
Subject(s)
Disease Outbreaks , Endocarditis, Bacterial/epidemiology , Heart Valve Prosthesis/adverse effects , Staphylococcal Infections/epidemiology , Carrier State , Equipment Contamination , Gloves, Surgical/standards , Humans , Staphylococcus epidermidis/isolation & purificationABSTRACT
Endemic infection in male surgical wards has been studied during three periods. There was some infection due to gram-negative bacilli, though Staphylococcus aureus remained as the single most important pathogen even in the absence of epidemic spread. Beta haemolytic streptococci were isolated in large numbers from the lesions of four patients with deep wound infection. Changes introduced in the pattern of post-operative care reduced sepsis due to Staph. aureus, reduced the severity of wound infection and apparently decreased the need for antibiotic therapy. Patients who became infected were retained in hospital longer than those who escaped clinically apparent infection.
