Evaluation of five membrane filtration methods for recovery of Cryptosporidium and Giardia isolates from water samples

We evaluated the efficiency of five membrane filters for recovery of Cryptosporidium parvum oocysts and Giardia lamblia cysts. These filters included the Pall Life Sciences Envirochek (EC) standard filtration and Envirochek high-volume (EC-HV) membrane filters, the Millipore flatbed membrane filter, the Sartorius flatbed membrane filter (SMF), and the Filta-Max (FM) depth filter. Distilled and surface water samples were spiked with 10 oocysts and 10 cysts/liter. We also evaluated the recovery efficiency of the EC and EC-HV filters after a 5-s backwash postfiltration. The backwashing was not applied to the other filtration methods because of the design of the filters. Oocysts and cysts were visualized by using a fluorescent monoclonal antibody staining technique. For distilled water, the highest percent recovery for both the oocysts and cysts was obtained with the FM depth filter. However, when a 5-s backwash was applied, the EC-HV membrane filter (EC-HV-R) was superior to other filters for recovery of both oocysts (n = 53 +/- 15.4 per 10 liters) and cysts (n = 59 +/- 11.5 per 10 liters). This was followed by results of the FM depth filter (oocysts, 28.2 +/- 8, P = 0.015; cysts, 49.8 +/- 12.2, P = 0.4260), and SMF (oocysts, 16.2 +/- 2.8, P = 0.0079; cysts, 35.2 +/- 3, P = 0.0079). Similar results were obtained with surface water samples. Giardia cysts were recovered at higher rates than were Cryptosporidium oocysts with all five filters, regardless of backwashing. Although the time differences for completion of filtration process were not significantly different among the procedures, the EC-HV filtration with 5-s backwash was less labor demanding.

A new confirmatory Neisseria gonorrhoeae real-time PCR assay targeting the porA pseudogene

The Roche Cobas Amplicor system is widely used for the detection of Neisseria gonorrhoeae but is known to cross react with some commensal Neisseria spp. Therefore, a confirmatory test is required. The most common target for confirmatory tests is the cppB gene of N. gonorrhoeae. However, the cppB gene is also present in other Neisseria spp. and is absent in some N. gonorrhoeae isolates. As a result, laboratories targeting this gene run the risk of obtaining both false-positive and false-negative results. In the study presented here, a newly developed N. gonorrhoeae LightCycler assay (NGpapLC) targeting the N. gonorrhoeae porA pseudogene was tested. The NGpapLC assay was used to test 282 clinical samples, and the results were compared to those obtained using a testing algorithm combining the Cobas Amplicor System (Roche Diagnostics, Sydney, Australia) and an in-house LightCycler assay targeting the cppB gene (cppB-LC). In addition, the specificity of the NGpapLC assay was investigated by testing a broad panel of bacteria including isolates of several Neisseria spp. The NGpapLC assay proved to have comparable clinical sensitivity to the cppB-LC assay. In addition, testing of the bacterial panel showed the NGpapLC assay to be highly specific for N. gonorrhoeae DNA. The results of this study show the NGpapLC assay is a suitable alternative to the cppB-LC assay for confirmation of N. gonorrhoeae-positive results obtained with Cobas Amplicor.

Investigation of unirhinal olfactory identification in antipsychotic-free patients experiencing a first-episode schizophrenia

Although olfactory deficits have been reported in patients with schizophrenia, few studies have examined whether these deficits are lateralized or investigated their possible clinical correlates. In this study, we administered the University of Pennsylvania Smell Identification Test (UPSIT) unirhinally (one nostril at a time) to 15 patients experiencing a first-episode of schizophrenia and 17 healthy comparison subjects. Clinical and olfactory assessments were conducted on the same day in patients while they were antipsychotic drug-free. Patients performed more poorly compared to healthy volunteers in their ability to identify odors across both nostrils, but there were no group differences in right and left nostril impairment. Among patients, greater deficits in grooming and hygiene correlated significantly and more strongly with poorer ability in identifying odors presented to the left compared to the right nostril. Our findings suggest that deficits in grooming and hygiene, including poor body odor, observed in patients experiencing a first-episode of schizophrenia are associated with an impairment in left nostril, and possibly left hemisphere, olfactory processing.

Sex differences in frontal lobe white matter microstructure: a DTI study

There is evidence that the brains of men and women are structurally different, but there are few data regarding possible sex differences in white matter microstructure. Using diffusion tensor imaging we assessed fractional anisotropy (FA) in the frontal lobe white matter on contiguous 5 mm slices in nine healthy male and 11 healthy female adults. Overall, women had higher FA in the left frontal lobe compared to men and a leftward asymmetry of FA in contrast to men, who showed no hemispheric asymmetry. Among women, greater leftward asymmetry of frontal lobe FA correlated significantly with better verbal comprehension and memory functioning. Our findings may be indicative of increased directional coherence and/or density of left hemisphere white matter fibers and a leftward asymmetry of this structural integrity among women compared to men.

Smaller anterior hippocampal formation volume in antipsychotic-naive patients with first-episode schizophrenia

OBJECTIVE

The authors investigated volumetric alterations of the anterior hippocampal formation in patients experiencing a first episode of schizophrenia relative to healthy comparison subjects.

METHOD

From contiguous 1.5-mm coronal magnetic resonance images, the hippocampal formation was divided into posterior and anterior segments, and the anterior hippocampal formation was separated from the amygdala. Volumes of the posterior and anterior hippocampal formation and amygdala were computed in 46 (31 male and 15 female) patients experiencing a first episode of schizophrenia and in 34 (21 male and 13 female) healthy comparison subjects. Twenty-four patients were antipsychotic naive at the time of the scan.

RESULTS

Patients had significantly reduced total (right plus left) anterior hippocampal formation volume relative to healthy comparison subjects but did not differ in volumes of either the posterior hippocampal formation or amygdala. Similar findings were obtained when analyses were restricted to the antipsychotic-naive subgroup of patients.

CONCLUSIONS

These findings suggest that volumetric abnormalities of the hippocampus-amygdala complex may be specific to the anterior hippocampal formation in patients experiencing a first episode of schizophrenia and are consistent with hypotheses regarding abnormal frontolimbic connectivity playing a role in the pathophysiology of the disorder.

Lack of normal association between cerebellar volume and neuropsychological functions in first-episode schizophrenia

OBJECTIVE

Functional neuroimaging studies have identified a role for the cerebellum in the neuropsychology of schizophrenia. Few studies, however, have examined the relationship between cerebellar size and neuropsychological functioning in schizophrenia. The authors' goal was to examine this relationship in patients and healthy comparison subjects.

METHOD

Total cerebellar volume was computed from magnetic resonance images in 48 male and 33 female patients experiencing a first episode of schizophrenia and in 14 male and nine female healthy comparison subjects. Patients and comparison subjects completed a comprehensive neuropsychological assessment encompassing six domains of functioning: executive, motor, language, visuospatial, memory, and attention. A global domain of functioning was computed as the mean of these six domains.

RESULTS

Larger cerebellar volume correlated significantly with better global functioning in healthy subjects but not among patients with schizophrenia; this relationship was significantly stronger in healthy subjects than in patients. Additional analyses revealed significant associations between cerebellar volume and visuospatial, executive, and memory functions in healthy volunteers but not among patients.

CONCLUSIONS

The cerebellum plays a role in higher cognitive functions in healthy individuals, and normal associations between cerebellar size and function are absent in patients experiencing a first episode of schizophrenia. These findings are consistent with neurobiological models implicating the cerebellum in the pathogenesis of schizophrenia.

Australia 2001 and the white powders: the Queensland experience

Starting in Canberra and spreading rapidly around the country from 12 October 2001 onwards, the laboratories of the Public Health Laboratory Network (PHLN) were placed on high alert as the nation responded to a heightened fear of anthrax mail attacks. This manifested itself in an incredible array of samples being submitted to laboratories for analysis and detection of possible anthrax contamination. Laboratory staff were placed under high stress in the performance of this work.

Long-term aminosalicylate therapy is under-used in patients with ulcerative colitis: a cross-sectional survey

BACKGROUND

There is evidence from case-control studies that aminosalicylate drugs can reduce colorectal cancer risk by 75-81% in patients with ulcerative colitis. Patients may fail to comply with long-term therapies, however, or may have been advised to discontinue treatment once in remission.

AIM

To describe the usage of long-term aminosalicylate therapy in patients with ulcerative colitis.

METHODS

A cross-sectional study was performed using data extracted from general practitioner clinical records on demographic features, extent and duration of disease, use of aminosalicylate therapy and specialist care.

RESULTS

Three hundred and sixty-three people had ulcerative colitis and no history of colorectal surgery. Ninety-five of 175 (54%) patients with proctitis, 78 of 123 (63%) patients with left-sided colitis and 28 of 45 (62%) patients with extensive colitis were currently taking an aminosalicylate drug. Those doing so were more likely to be under specialist care than to be definitely or possibly discharged (odds ratio, 4.9; 95% confidence interval, 2.9-8.4). The likelihood of current aminosalicylate therapy was not related to gender or the extent of disease, but was negatively related to the duration of disease.

CONCLUSIONS

A substantial minority of patients with ulcerative colitis does not take long-term aminosalicylate therapy. Those who do are more likely to be under specialist care, to be older or to have disease of shorter duration.

Effect of cisternal and ventricular blood on risk of delayed cerebral ischemia after subarachnoid hemorrhage: the Fisher scale revisited

BACKGROUND AND PURPOSE

Thick cisternal clot on CT is a well-recognized risk factor for delayed cerebral ischemia (DCI) after subarachnoid hemorrhage (SAH). Whether intraventricular hemorrhage (IVH) or intracerebral hemorrhage (ICH) predisposes to DCI is unclear. The Fisher CT grading scale identifies thick SAH but does not separately account for IVH or ICH.

METHODS

We studied 276 consecutively admitted patients with an available admission CT scan performed within 72 hours of onset. Demographic, clinical, laboratory, and neuroimaging data were recorded, and the amount and location of SAH, IVH, and ICH on admission CT scans were quantified. The relationship between these variables and DCI was analyzed separately and in combination with multiple logistic regression.

RESULTS

DCI developed in 20% of patients (54 of 276). Among SAH variables, thick clot completely filling any cistern or fissure was the best predictor of DCI (P=0.008), and among IVH variables, blood in both lateral ventricles was most predictive (P=0.001). These variables had independent predictive value for DCI in a multivariate analysis of CT findings, and both were included in a final multivariate model when evaluated in conjunction with other clinical risk factors: IVH (OR 4.1, 95% CI 1.7 to 9.8), SAH (OR 2.3, 95% CI 1.5 to 9.5), mean arterial pressure >112 mm Hg (OR 4.9, 95% CI 2.1 to 11.4), and transcranial Doppler mean velocity >140 cm/s within 5 days of hemorrhage (OR 3.8, 95% CI 1.5 to 9.5). Similar results were obtained in a repeat analysis with infarction due to vasospasm as the dependent variable.

CONCLUSIONS

SAH completely filling any cistern or fissure and IVH in the lateral ventricles are both risk factors for DCI, and their risk is additive. We propose a new SAH rating scale that accounts for the independent predictive value of subarachnoid and ventricular blood for DCI.

Surveillance of antibiotic resistance in invasive isolates of Neisseria meningitidis in Australia 1994-1999

A total of 1434 strains of Neisseria meningitidis isolated from cases of invasive meningococcal disease (IMD) in Australia between 1994 and 1999 were examined by standard methods for susceptibility to antibiotics used for treatment and prophylaxis. The proportion of isolates fully susceptible to penicillin decreased from 45% in 1994 to 26% in 1999 (P<0.001). All the other isolates were less sensitive to penicillin except for two meningococci with a penicillin MIC of 1 mg/l. The geometric mean penicillin MIC increased from 0.045 to 0.065 mg/l from 1994 to 1999. There was no significant difference in the geometric mean penicillin MICs of serogroup B and serogroup C meningococci. Penicillin susceptibility was significantly associated with a poorer outcome. Isolates from survivors of IMD had a higher geometric mean penicillin MIC (0.06 mg/l) than those from fatal cases (0.048 mg/l) (P< 0.001). This suggests that factors other than the decrease in susceptibility to penicillin observed were more relevant to outcome in IMD. All isolates were fully susceptible to ceftriaxone. Rifampicin resistance was infrequent (eight isolates in 6 years) and sporadic. A single isolate had decreased quinolone susceptibility. Despite the significant shift in susceptibility to penicillin recorded, this group of antibiotics remains a suitable treatment for IMD in Australia.

Children's hospitals collaborate to improve quality of care

The Child Health Accountability Initiative brought together 35 chief executive officers, physicians, and researchers representing 12 children's hospitals and charged them with what most would think is a lofty goal: to improve health outcomes for America's children. After a rigorous and often highly debated selection process, two data-driven performance improvement projects were rapidly set in motion and implemented in each of the hospitals, with significant results--all within the first year. The initiative's breadth, scope, and speed may serve as a model for other healthcare collaboratives.

Clinical trial of an air-circulating cooling blanket for fever control in critically ill neurologic patients

OBJECTIVE

To evaluate the efficacy of an air-circulating cooling blanket for reducing body temperature in febrile neuro-ICU patients treated with acetaminophen.

METHODS

Two-hundred twenty consecutively admitted neuro-ICU patients whose tympanic membrane temperature reached or exceeded 101 degrees F (38.3 degrees C) were randomly assigned to receive acetaminophen (650 mg every 4 hours) alone (n = 107) or acetaminophen plus air blanket therapy (n = 113). After 24 hours of treatment, the authors compared the proportion of subjects who attained treatment success (T < or = 99 degrees F) or treatment failure (T > or = 101 degrees F for 2 consecutive hours) using the chi(2) test and the time to reach these endpoints using Kaplan-Meier survival analysis.

MAIN RESULTS

Air blanket therapy resulted in a small increase in the proportion of subjects with treatment success (44% versus 36%, chi(2) p = 0.19, log rank p = 0.10) and a similar small reduction in the proportion of patients with treatment failure (42% versus 53%, chi(2) p = 0.11, log-rank p = 0.21), compared with treatment with acetaminophen alone. Approximately one third of patients in both groups remained febrile after randomization and "failed" after the first 2 hours of treatment. Twelve percent of patients assigned to air blanket therapy refused or were unable to tolerate treatment, compared with 2% of patients treated with acetaminophen alone (p = 0.005).

CONCLUSIONS

Treatment with an air-circulating cooling blanket did not effectively reduce body temperature in febrile neuro-ICU patients treated with acetaminophen. More effective interventions are needed to maintain normothermia in patients at risk for fever-related brain damage.

A randomized, double blind study in young healthy adults comparing cell mediated and humoral immune responses induced by influenza ISCOM vaccines and conventional vaccines

Although current influenza vaccines have been shown to reduce influenza-related morbidity and mortality, there is a desire to develop more efficacious products. Vaccines which can induce CD8(+) cytotoxic T cell (CTL) responses in addition to strong antibody responses may be more effective in preventing disease since it has been demonstrated that CTL contribute to protective immunity, even against drift variants of influenza A viruses. The immunogenicity of two types of experimental influenza vaccines, which were based on immune stimulating complexes (ISCOM), were evaluated and compared with a conventional non-adjuvanted inactivated split virion vaccine, after immunization of human volunteers. In this randomized, double blind study, it was shown that the ISCOM vaccines altered the kinetics of the serum antibody response, resulting in more rapid titer rises against the vaccine strains. This accelerated antibody response coincided with enhanced in vitro proliferative T cell responses, which were observed shortly after vaccination. In addition, CTL responses were observed in a higher proportion of the vaccinees receiving an ISCOM vaccine, than in vaccinees receiving the conventional influenza vaccine.

Specification for signal processing and data handling used for infant pulmonary function testing. ERS/ATS Task Force on Standards for Infant Respiratory Function Testing. European Respiratory Society/American Thoracic Society

The aim of this present paper is to define minimal performance criteria for the separate items comprising signal processing and data handling used to measure respiratory function in infants. These guidelines cover numerous aspects including: signal processing, data handling and subsequent analysis, reporting of results, demographics and handling of reference values. Adherence to these guidelines should ensure that infant lung function measurements can be performed with an acceptable degree of safety, precision, and reproducibility. Furthermore, they will facilitate multicentre collection of data and the performance of clinical investigations.

Specifications for equipment used for infant pulmonary function testing. ERS/ATS Task Force on Standards for Infant Respiratory Function Testing. European Respiratory Society/ American Thoracic Society

The aim of this position paper is to define minimal performance criteria for the separate items comprising equipment used to measure respiratory function in infants together with overall performance criteria for the assembled pieces of such equipment. These guidelines cover numerous aspects including: 1) safety, 2) documentation and maintenance of equipment, 3) physical characteristics of mechanical parts and signal transducers, and 4) data acquisition. Further, validation procedures for individual components as well as for the integrated equipment are recommended. Adherence to these guidelines should ensure that infant lung function measurements can be performed with an acceptable degree of safety, precision and reproducibility. They will also facilitate multicentre collection of data and performance of clinical investigations. Manufacturers of infant respiratory function equipment should make every effort to comply with these guidelines, which represent the current standards of paediatric health professionals in this field.

Azithromycin vs cefuroxime plus erythromycin for empirical treatment of community-acquired pneumonia in hospitalized patients: a prospective, randomized, multicenter trial

OBJECTIVE

To compare the efficacy and safety of azithromycin dihydrate monotherapy with those of a combination of cefuroxime axetil plus erythromycin as empirical therapy for community-acquired pneumonia in hospitalized patients.

METHODS

Patients were enrolled in a prospective, randomized, multicenter study. The standard therapy of cefuroxime plus erythromycin was consistent with the American Thoracic Society, Canadian Community-Acquired Pneumonia Consensus Group, and Infectious Disease Society of America consensus guidelines. The doses were intravenous azithromycin (500 mg once daily) followed by oral azithromycin (500 mg once daily), intravenous cefuroxime (750 mg every 8 hours), followed by oral cefuroxime axetil (500 mg twice daily), and erythromycin (500-1000 mg) intravenously or orally every 6 hours. Randomization was stratified by severity of illness and age. Patients who were immunosuppressed or residing in nursing homes were excluded.

RESULTS

Data from 145 patients (67 received azithromycin and 78 received cefuroxime plus erythromycin) were evaluable. Streptococcus pneumoniae and Haemophilus influenzae were isolated in 19% (28/145) and 13% (19/145), respectively. The atypical pathogens accounted for 33% (48/145) of the etiologic diagnoses; Legionella pneumophila, Chlamydia pneumoniae, and Mycoplasma pneumoniae were identified in 14% (20/ 145), 10% (15/145), and 9% (13/145), respectively. Clinical cure was achieved in 91% (61/67) of the patients in the azithromycin group and 91% (71/78) in the cefuroxime plus erythromycin group. Adverse events (intravenous catheter site reactions, gastrointestinal tract disturbances) were significantly more common in patients who received cefuroxime plus erythromycin (49% [30/78]) than in patients who received azithromycin (12% [8/67]) (P<.001).

CONCLUSIONS

Treatment with azithromycin was as effective as cefuroxime plus erythromycin in the empirical management of community-acquired pneumonia in immunocompetent patients who were hospitalized. Azithromycin was well tolerated.

Elective versus symptomatic antibiotic treatment in cystic fibrosis patients with chronic Pseudomonas infection of the lungs

BACKGROUND

A previous retrospective study suggested that a policy of regular anti-pseudomonal antibiotic treatment improved pulmonary function and increased survival in patients with cystic fibrosis chronically infected with Pseudomonas species. The results of a prospective multicentre study to compare the effects on pulmonary function and mortality of three monthly elective anti-pseudomonal antibiotic treatment with conventional symptomatic treatment are reported.

METHODS

Sixty patients with cystic fibrosis, chronically infected with P aeruginosa, were randomised to the two treatment arms (elective or symptomatic) and followed clinically at yearly reviews. The major end points were changes in forced expiratory volume in one second (FEV(1)) and forced vital capacity (FVC). Survival was a secondary end point.

RESULTS

Patients in the symptomatic group received a mean of three antibiotic treatments each year and those in the elective group received four antibiotic treatments during each year of the study. No significant differences in FEV(1) and FVC were found between the two groups after three years. There was a statistically non-significant higher rate of deaths in the elective group (n = 4), three of which were associated with B cepacia infection, compared with the symptomatic group (n = 0).

CONCLUSIONS

This study did not demonstrate an advantage of a policy of elective antibiotic treatment over symptomatic treatment in patients with cystic fibrosis chronically infected with Pseudomonas species.

Program for licensure for international medical graduates in British Columbia: 7 years' experience

British Columbia has funded a program for licensure for international medical graduates since 1992, providing 2 entry positions per year for postgraduate training. Each year 25-35 candidates are eligible for the program, 13-16 enter the evaluation process, 4 go on to a clinical evaluation and 2 are offered funding by the Ministry of Health. Other candidates may access community funding if they meet the requirements of the program. Twenty of 26 candidates have successfully completed the postgraduate training and achieved full licensure; 6 are still in training. In this article we describe the development of the program, the evaluation and selection process, characteristics of the candidates and the outcomes of the program.

Effects of risperidone on auditory event-related potentials in schizophrenia

Schizophrenia is associated with cognitive deficits for which treatments remain elusive. The effects of risperidone (an antipsychotic differing in some of its pharmacological properties from typical agents) on cognitive deficits have not been extensively investigated. Mismatch negativity (MMN), N2 and P3 are cognitive event-related potentials that index preattentive (MMN) and attention-dependent information processing (N2, P3) and provide a measure of cognitive deficits in schizophrenia. The effects of risperidone treatment on MMN, N2 and P3 generation in chronic schizophrenic patients were investigated in an open- label, uncontrolled study. Risperidone treatment significantly reduced psychotic symptoms. It was associated with a decrease of peak latencies, particularly pronounced for P3. However, it did not significantly affect abnormal MMNor P3 amplitudes. The results suggest an effect of risperidone on processing speed, particularly in attention-dependent tasks. These results are in agreement with findings in recent studies on the cognitive effects of risperidone.

An outbreak of Campylobacter enteritis on an island resort, north Queensland

An outbreak of Campylobacter enteritis among staff on a resort island in north Queensland is reported. Untreated rainwater and food from the staff dining room were initially suspected as possible sources of infection but Campylobacter species were not isolated from any environmental samples. Faecal contamination was detected in four rainwater tanks. A case control study involved a total of 23 cases (7 confirmed and 16 probable), 3 of whom required hospitalisation. There was a strong association between gastrointestinal illness and consumption of water from a dispenser in the staff restaurant that had probably been filled from one of the contaminated tanks. We conclude that this was probably a waterborne outbreak and postulate that Campylobacter species were introduced into one or more of the tanks by contamination with the faeces of wild animals.