The severe acute respiratory syndrome coronavirus in tears.

BACKGROUND: Severe acute respiratory syndrome (SARS) is a new infectious disease that caused a global outbreak in 2003. Research has shown that it is caused by a novel coronavirus. A series of cases is reported where polymerase chain reaction (PCR) testing on tears had demonstrated the presence of the virus. Detection of ocular infection from tears using the PCR technique has been widely used by ophthalmologists to diagnose infections for other viruses. METHODS: This is a case series report from cases classified as probable or suspect SARS cases. Tear samples were collected from 36 consecutive patients who were suspected of having SARS in Singapore over a period of 12 days (7-18 April 2003), and analysed by PCR using protocols developed by the WHO network of laboratories. RESULTS: Three patients with probable SARS (one female and two male patients) had positive results from their tear samples. Tear samples were used to confirm SARS in the female patient, who was positive only from her tears. The positive specimens were found in cases sampled early in their course of infection. CONCLUSIONS: This is the first case series reported with the detection of the SARS coronavirus from tears, and has important implications for the practice of ophthalmology and medicine. The ability to detect and isolate the virus in the early phase of the disease may be an important diagnostic tool for future patients and tear sampling is both simple and easily repeatable. Many healthcare workers are in close proximity to the eyes of patients and this may be a source of spread among healthcare workers and inoculating patients. Ophthalmic practices may need to change as more stringent barrier methods, appropriate quarantine, and isolation measures are vital when managing patients with SARS.

Fluconazole susceptibility of Candida species in Singapore by disc diffusion test.

INTRODUCTION: Resistance of Candida species to fluconazole has been increasingly reported worldwide. To date, the prevalence of resistance to fluconazole in Singapore is unknown. The aim of this study was to use a newly described agar disc diffusion method to study levels of susceptibility of Candida species to fluconazole in several hospitals in Singapore. MATERIALS AND METHODS: Three hundred and ninety Candida isolates from clinical specimens collected from different sites were tested, of which 191 isolates (49.0%) were C. albicans, 69 (17.7%) were C. parapsilosis, 59 (15.1%) were C. glabrata, 51 (13.1%) were C. tropicalis and 4 (1.0%) were C. krusei. Susceptibility testing was performed using 25 micrograms fluconazole discs and standard Mueller-Hinton agar supplemented with 2% glucose and 0.5 microgram/mL of methylene blue. RESULTS: Overall, 381 (97.7%) isolates were susceptible, 6 (1.5%) were susceptible dose-dependent, and 3 (0.8%) were resistant to fluconazole. Of the individual species, 99.5% of C. albicans, 93.2% of C. glabrata, 0% of C. krusei, and 100% of C. parapsilosis, C. tropicalis and other Candida species were susceptible. CONCLUSION: The resistance of Candida species to fluconazole, as measured using a new disc diffusion method, is low in Singapore, with the exception of C. krusei. Fluconazole remains a useful agent for the treatment of candidiasis in this country.

Vibrio vulnificus septicaemia.

Vibrio vulnificus is an opportunistic pathogen capable of causing a fulminant septicaemia in susceptible patients. Underlying chronic diseases such as liver impairment and immunosuppression are important factors contributing to the severity of the infection and outcome. Early suspicion and diagnosis with appropriate antibiotic therapy is important as delay can adversely affect outcome. For those who develop tissue necrotizing fasciitis, early surgical debridement is recommended to allow better penetration of antibiotics and also to reduce the severity of the septicaemia. Mortality is quoted as between 50% and 90%. Current antibiotic recommendations are intravenous ceftazidime 2 g tds and doxycycline 100 mg od.

Gastrointestinal colonisation of vancomycin-resistant enterococcus in a Singapore teaching hospital.

Vancomycin-resistant enterococcus (VRE) has become an important nosocomial pathogen in many countries but is still rare in Singapore. A study was conducted from January to March 1997 at a 900-bed teaching hospital to determine the prevalence of intestinal colonisation of VRE in the patient population. A total of 299 consecutive stool specimens received by the microbiology laboratory for routine testing were plated onto two different selective media for comparison. VRE isolated were phenotypically characterised using minimum inhibitory concentrations (MICs) to vancomycin and teicoplanin and then typed using pulsed-field gel electrophoresis (PFGE) with Smal digestion of DNA. VRE were detected in the stool of 35 patients (12.3%). This group consisted of four isolates with VanB (one Enterococcus faecalis and three E. faecium) and 31 isolates with VanC (30 E. casseliflavus and one E. gallinarum). Two patients (0.7%) carried isolates (both VanB) with high level resistance to vancomycin (MIC > or = 256 microg/ml) while the rest had isolates of low level resistance (MIC = 8 microg/ml). Except for isolates from the same patients, PFGE patterns were diverse, suggesting that the VRE isolates were genotypically different and possibly introduced from many sources. This study demonstrates that VRE colonisation is not uncommon in the Singapore patient population.

Protective antibodies to hepatitis B virus in haemophiliacs.

Haemophilic patients are at increased risk from hepatitis B virus infection because of their need for blood product therapy. They are potentially poor responders to hepatitis B vaccine due to immunological abnormalities resulting from two causes: infection with the human immunodeficiency virus and treatment with clotting factor concentrates. The protective antibody response to hepatitis B virus in vaccinated haemophiliacs was investigated using a competitive enzyme-linked immunosorbent assay which employs a monoclonal antibody, RF-HBs-1, that recognises a virus-neutralising epitope on HBsAg. Serum samples from 55 haemophilic patients were studied at 7, 12, and 24 months after the first injection with HB vaccine. Twenty-four vaccinated normal subjects were used as controls. The level of neutralising antibody was found to correlate with the polyclonal anti-HBs response in the majority of subjects in both the control and patient groups. There was a small but statistically significant reduction in both antibody responses in the patients compared with the normal controls. Treatment with FVIII or FIX concentrate did not influence the antibody response in the patients. Eleven of the haemophilic patients were anti-HIV seropositive. This group had a significantly lower antibody response than anti-HIV negative patients, and this correlated with the duration of anti-HIV seropositivity, rather than with their T4 counts. We conclude that, following vaccination, the majority of haemophiliacs are able to mount a protective antibody response to hepatitis B virus. HIV infection was found to be the sole cause of immunological suppression of this response.