Florence Yap

Increase in Methicillin-Resistant Staphylococcus aureus Acquisition Rate and Change in Pathogen Pattern Associated with an Outbreak of Severe Acute Respiratory Syndrome

Abstract Background. An outbreak of severe acute respiratory syndrome (SARS) occurred in our 22-bed intensive care unit (ICU; Prince of Wales Hospital, Hong Kong, HKSAR, China) from 12 March to 31 May 2003, when only patients with SARS were admitted. This period was characterized by the upgrading of infection control precautions, which included the wearing of gloves and gowns all the time, an extensive use of steroids, and a change in antibiotic prescribing practices. The pattern of endemic pathogenic organisms, the rates of acquisition of methicillin-resistant Staphylococcus aureus (MRSA), and the rates of ventilator-associated pneumonia (VAP) were compared with those of the pre-SARS and post-SARS periods. Methods. Data on pathogenic isolates were obtained from the microbiology department (Prince of Wales Hospital). Data on MRSA acquisition and VAP rates were collected prospectively. MRSA screening was performed for all ICU patients. A case of MRSA carriage was defined as an instance in which MRSA was recovered from any site in a patient, and cases were classified as imported or ICU-acquired if the first MRSA isolate was recovered within 72 h of ICU admission or after 72 h in the ICU, respectively. Results. During the SARS period in the ICU, there was an increase in the rate of isolation of MRSA and Stenotrophomonas and Candida species but a disappearance of Pseudomonas and Klebsiella species. The MRSA acquisition rate was also increased: it was 3.53% (3.53 cases per 100 admissions) during the pre-SARS period, 25.30% during the SARS period, and 2.21% during the post-SARS period (P < .001). The VAP rate was high, at 36.5 episodes per 1000 ventilator-days, and 47% of episodes were caused by MRSA. Conclusions. A SARS outbreak in the ICU led to changes in the pathogen pattern and the MRSA acquisition rate. The data suggest that MRSA cross-transmission may be increased if gloves and gowns are worn all the time.

Immunofluorescence Assay for Serologic Diagnosis of SARS

We evaluated a virus-infected cell-based indirect immunofluorescence assay for detecting anti–severe acute respiratory syndrome-associated coronavirus (SARS-CoV) immunoglobulin (Ig) G antibody. All confirmed SARS cases demonstrated seroconversion or fourfold rise in IgG antibody titer; no control was positive. Sensitivity and specificity of this assay were both 100%. Immunofluorescence assay can ascertain the status of SARS-CoV infection.

Limitation of life support: Frequency and practice in a Hong Kong intensive care unit

ObjectiveTo examine the frequency and the decision-making processes involved in limiting (withdrawing and withholding) life support therapy in critically ill Chinese patients in the intensive care unit. DesignProspective survey of patients who had life support limited between April 1997 and March 1999. SettingMedical and surgical intensive care unit of a teaching hospital. PatientsAll patients admitted to the intensive care unit of the Prince of Wales Hospital who subsequently died and/or had life support limited. Brain-dead patients were excluded from analysis. InterventionsNone. Measurements and Main ResultsOf 490 patients who died in the intensive care unit, limitation of life support occurred in 288 (58.8%). Relatives or patients requested limitation of life support in 32 cases (11%). The family and/or patient concurred with limitation of life support in 273 occasions (95%). Therapy was withheld in 30.8% and withdrawn in 28.0% of deaths. Therapy limited included inotropes, additional oxygen, and renal replacement therapy. ConclusionsLimitation of therapy in dying Chinese patients occurs frequently in intensive care patients, and both patients and relatives concur with medical decisions to limit therapy in these patients. Withholding therapy rather than withdrawing therapy occurs more frequently than in Western populations.