In vitro activities of doripenem and other carbapenems against clinically important bacteria isolated in intensive care units: nationwide data from the SMART Programme.

This nationwide surveillance of clinically important bacteria from the intensive care units (ICUs) of major teaching hospitals throughout Taiwan investigated the susceptibilities to doripenem and other comparator carbapenems from September through November 2005. Minimum inhibitory concentrations (MICs) were determined for 1,311 clinical isolates using the broth microdilution method according to Clinical and Laboratory Standards Institute (CLSI) 2005 guidelines. Doripenem showed similar (within four-fold difference of MICs) in vitro activity to meropenem for Enterobacteriaceae and probably comparable activity to meropenem against important nosocomial non-fermentative Gram-negative bacilli (NFGNBs), including Pseudomonas aeruginosa, Acinetobacter baumannii and Burkholderia cepacia. Among the four carbapenems analysed, doripenem and meropenem exhibited better in vitro activity than imipenem or ertapenem against extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae and Escherichia coli isolates. However, the meropenem MIC(90) against ESBL-producing K. pneumoniae isolates was 2 microg/ml. Besides, doripenem with the MIC(90) of 0.5 microg/ml to Streptococcus pneumoniae possibly suggested its potential therapeutic effect regarding community-acquired pneumonia. Because of the heavy resistance burden in Taiwan, closely monitoring the evolutionary trend of carbapenem susceptibilities against clinically important pathogens is crucial in the future.

Nationwide surveillance of antimicrobial resistance among Enterobacteriaceae in intensive care units in Taiwan.

To determine the antimicrobial resistance profiles among clinical isolates of Enterobacteriaceae in Taiwanese intensive care units (ICUs), a national surveillance of antibiotic resistance among important Enterobacteriaceae was conducted from September 2005 through November 2005 at the ICUs of ten major teaching hospitals in Taiwan. A total of 574 Enterobacteriaceae isolates recovered from various clinical samples of our ICU patients were submitted for in vitro test. Minimum inhibitory concentrations (MICs) of these isolates to 18 antimicrobial agents were determined by the broth microdilution method. The prevalences of Enterobacteriaceae isolates with phenotypic extended-spectrum beta-lactamase (ESBL) production were 26% in Klebsiella pneumoniae, 16% in Serratia marcescens, 14% in Escherichia coli, and 13% in Proteus mirabilis, in which a significantly rising prevalence of ESBL production among K. pneumoniae was noted (p = 0.002) when compared with a previous Taiwanese survey in 2000. Heterogeneous resistance to various fluoroquinolones was found among our Enterobacteriaceae isolates, except for Enterobacter cloacae. Emergence of ertapenem-resistant isolates of E. coli, K. pneumoniae, E. cloacae, and S. marcescens was noted. Gradually increasing rates of drug-resistant Enterobacteriaceae were noted in Taiwanese ICUs. Periodic surveillance of the evolutionary trend of antimicrobial resistance among ICU isolates is crucial for starting appropriately empirical antimicrobial therapy in the future.

Nationwide surveillance of antimicrobial resistance among Haemophilus influenzae and Streptococcus pneumoniae in intensive care units in Taiwan.

A nationwide susceptibility surveillance of Streptococcus pneumoniae and Haemophilus influenzae isolates collected from patients treated at the intensive care units (ICUs) of ten Taiwanese major teaching hospitals was conducted from September 2005 through November 2005. High rates of resistance (intermediate/resistant) of S. pneumoniae to penicillin (85% resistance), ceftriaxone (46%/20%), and cefepime (43%/15%) by meningitis criteria, and in contrast, non-susceptibilities (intermediate/resistant) to penicillin (0%/0%), ceftriaxone (20%/0%) and cefepime (15%/0%) by non-meningitis criteria were noted (p values < 0.05) by the Clinical and Laboratory Standards Institute 2008. Resistant rate of S. pneumoniae to azithromycin was also high (63%). S. pneumoniae isolates were significantly more susceptible to ertapenem (87%) than to imipenem (39%) and meropenem (44%) (p values < 0.05). Rates of non-susceptibilities of H. influenzae isolates to ampicillin and cefaclor were high (55% and 45%, respectively). No beta-lactamase-negative ampicillin-resistant (BLNAR) H. influenzae isolates were found. Imipenem has a notably higher MIC(90) value (8 microg/ml) for H. influenzae than that of the other two carbapenems. Tigecycline showed good in vitro activities against these two respiratory pathogens. High rates of resistance among isolates of S. pneumoniae and H. influenzae continue to exist in the ICUs of Taiwan.

Clinical manifestations of human immunodeficiency virus infection in Haitian children.

OBJECTIVE: This study was designed to describe the characteristics of HIV-1 infection in children in Haiti and to assess its impact on morbidity and mortality. BACKGROUND: Throughout the developing world the female-to-male ratio of HIV-1 infection approaches 1:1, leading to a tremendous burden of vertically transmitted HIV-1 infection. The frequency of transmission, progression of disease and AIDS-defining clinical illnesses are not as well-described in this setting as in the industrial world. METHODS: Children were identified as being HIV-1-seropositive from case findings among family members of individuals presenting for screening at the GHESKIO Centers in Port-au-Prince, Haiti. Children who were seronegative from the same population were also enrolled and both groups were followed at regular intervals. The clinical course and illnesses associated with HIV infection were documented. RESULTS: Rapid progression to symptomatic disease and death was seen and a battery of physical findings enabled a clinician over time to assign with high sensitivity and specificity the diagnosis of AIDS to a child. Although many findings are similar, the presentation of HIV-1 infection in Haiti differed in significant ways from observations in the industrial world. In particular signs of malnutrition, failure to thrive and tuberculosis were more common in the Haitian population. CONCLUSION: Pediatric HIV-1 infection in Haiti differs significantly from the illness in the industrial world. Early mortality poses a particular difficulty in diagnosing and ascribing mortality to HIV-1 infection.

The natural history of human immunodeficiency virus 1 infection in Haitian infants.

OBJECTIVES: The current study followed HIV-infected women through pregnancy and their infants through the first 2 years of life to determine the rate of vertical transmission of HIV infection from Haitian women, factors in maternal health and obstetrical history that might influence such transmission and the natural history of HIV infection in their affected offspring. STUDY DESIGN: The medical histories of 81 infants born of HIV-infected women and of a control group of 88 infants born to uninfected women were documented with close clinical and serologic follow-up. In addition to standard tests for persistence of HIV antibodies, the use of acid-dissociated p24 assays enabled us to assign some additional infants to the HIV-infected cohort. RESULTS: Transmission could be documented in 27% of infants born to HIV-infected women. Excess early deaths occurred in infants of HIV-infected women in Port-au-Prince with 60% of infected infants dead by 6 months of age. This is a more accelerated mortality than that in a group of 42 HIV-infected infants born of Haitian mothers living in Miami where 10% were dead at 6 months. Clinically, in 6 of 19 deaths in HIV-infected children in Haiti, failure to thrive and gastroenteritis lead to a systemic infection manifested as meningitis, sepsis or pneumonia as the immediate cause of death. CONCLUSIONS: Early mortality attributable to perinatally acquired AIDS was identified in Haiti. The comparison of data from Miami and Port-au-Prince suggests that environmental exposures in developing countries may be more operative in this early mortality than viral strain or maternal host factors, both of which might be expected to be similar between the two groups of Haitian ethnicity.

Cryptococcaemia: clinical features and prognostic factors.

BACKGROUND: Limited data are available on the clinical significance of cryptococcaemia, which occurs in 10-30% of patients with cryptococcal diseases. AIM: To describe the clinical features of cryptococcaemia and identify its prognostic factors. STUDY DESIGN: Retrospective cohort study. METHODS: All adult patients with Cryptococcus neoformans isolated from blood culture at the National Taiwan University Hospital, Taipei, 1981-2001, were included. Demographic and clinical information was obtained from medical records. RESULTS: Fifty-two patients were diagnosed and treated for cryptococcaemia. Acquired immunodeficiency syndrome (24/52, 46%), immunosuppressive therapy (12/52, 23%) and decompensated liver cirrhosis (11/52, 21%) were the three major predisposing conditions. Forty-two patients (81%, n=52) had sepsis, including four patients with septic shock, when blood cultures were obtained. Of the 38 patients in whom lumbar puncture was done, cerebrospinal fluid culture showed meningeal involvement in 32 (84%). The 30-day fatality rate was 37%. Liver cirrhosis, septic shock at presentation, an initial APACHE II score >/=20, age >/=60 years and female gender were associated with mortality under univariate analysis. Starting antifungal therapy within 48 h after blood culture was associated with improved survival. Under multivariate analysis, liver cirrhosis remained a strong independent predictor of mortality at 30 days after blood culture (HR 16.3, 95%CI 2.6-101.7, p=0.003). DISCUSSION: Patients with cryptococcaemia have a high risk of mortality within 30 days. Sepsis and meningeal involvement are common. Those with liver cirrhosis have a particularly poor prognosis.

Invasive infections due to vancomycin-resistant enterococci in adult patients.

Since 1990, vancomycin-resistant enterococci have emerged as important nosocomial pathogens. Invasive infections caused by these organisms have challenged most physicians because they are resistant to multiple antibiotics. We analyzed the clinical characteristics of adult patients with invasive vancomycin-resistant enterococci infections in the National Taiwan University Hospital from January 1993 through December 2000. A total of 11 adult patients were identified, 9 of whom had bacteremia (7 caused by vancomycin-resistant Enterococcus faecalis and 2 by vancomycin-resistant Enterococcus faecium) and one each had thoracic empyema (vancomycin-resistant E. faecium) and peritonitis (vancomycin-resistant E. faecium). Five patients had rectal swab cultures positive for vancomycin-resistant enterococci; 4 of them had underlying malignancies. The majority (91%) of these patients had prolonged hospitalization and prior long-term use of broad-spectrum cephalosporins (ceftriaxone, ceftazidime, or cefepime) or anti-anaerobic agents (clindamycin or metronidazole). The crude mortality rate was 64%. In conclusion, invasive infection caused by vancomycin-resistant enterococci is an emerging problem among hospitalized patients in Taiwan, particularly those with severe underlying diseases and exposure to multiple antibiotics.

Elizabethkingia meningoseptica: an important emerging pathogen causing healthcare-associated infections.

Elizabethkingia meningoseptica has been deemed a potentially important threat to patients in critical care areas because of its multidrug-resistant phenotype and its ability to adapt to various environments. This review considers the incidence, factors which predispose to, and clinical features of, E. meningoseptica sepsis, along with antimicrobial susceptibility patterns of clinical E. meningoseptica isolates and reportedly successful measures for the prevention and control of infections caused by this bacterium. The English-language literature from the PubMed database was reviewed. The incidence of E. meningoseptica bacteraemia has increased over the last decade. Patients at high risk of E. meningoseptica infection include preterm children, the immunocompromised and those exposed to antibiotics in critical care units. Vancomycin, rifampicin, newer fluoroquinolones, piperacillin-tazobactam, minocycline and possibly tigecycline are preferred empirical choices for E. meningoseptica infection according to in-vitro susceptibility data. Combination therapy has been used for infections not responding to single agents. Saline, lipid, and chlorhexidine gluconate solutions as well as contaminated sinks have been implicated as sources of infection following outbreak investigations. In addition to reinforcement of standard infection control measures, actions that have successfully terminated E. meningoseptica outbreaks include pre-emptive contact isolation, systematic investigations to identify the source of the bacterium and thorough cleaning of equipment and environmental surfaces. As the clinical complexity and incidence of E. meningoseptica infections increase, there is a need for heightened awareness of the potential for this bacterium to cause outbreaks. This will permit timely initiation of active surveillance for infected/colonized patients as well as investigations to identify the likely source of the bacterium, which will, in turn, allow implementation of appropriate infection control measures.

Effect of isoniazid prophylaxis on incidence of active tuberculosis and progression of HIV infection.

Tuberculosis occurring with human immunodeficiency virus (HIV) infection is a serious and growing public health problem. We have carried out a randomised clinical trial of a 12-month course of isoniazid plus vitamin B6 versus vitamin B6 alone in Port-au-Prince, Haiti, to assess the efficacy of isoniazid in preventing active tuberculosis in symptom-free HIV-infected individuals. The effect of prophylaxis on the development of HIV disease, AIDS, and death was also investigated. 118 subjects were assigned treatment with isoniazid plus B6 (n = 58) or B6 alone (n = 60) between 1986 and 1989. The treatment groups were similar at study entry in demographic, clinical, and immunological characteristics. Interim analysis in 1990 revealed no significant difference in tuberculosis outcome measures. Follow-up was continued until 1992, at which time significant protection by isoniazid against the development of tuberculosis was apparent, both for the whole study population and for subjects positive for purified protein derivative of tuberculin (PPD). The incidence of tuberculosis was lower in isoniazid recipients than in patients who received B6 alone (2.2 vs 7.5 per 100 person-years). The relative risk of tuberculosis was 3.4 (95% CI 1.1-10.6) for B6 alone versus isoniazid plus B6 (p < 0.05). Isoniazid also delayed progression to HIV disease and AIDS and death. Thus isoniazid effectively decreases the incidence of tuberculosis and delays the onset of HIV-related disease in symptom-free HIV-seropositive individuals. Isoniazid prophylaxis should be considered for HIV-seropositive, PPD-positive subjects, and may also be appropriate for PPD-negative patients in areas where tuberculosis is highly endemic.