Thrombotic thrombocytopenic purpura following transurethral resection of the prostate

A 65-year old man developed anaemia, profound thrombocytopenia and acute renal failure 2 days after transurethral resection of the prostate. Based on the clinical picture and blood film evidence of microangiopathic haemolysis, thrombotic thrombocytopenic purpura was diagnosed. The patient was treated with a course of plasma exchange, renal replacement therapy and methylprednisolone and made a good recovery. Thrombotic thrombocytopenic purpura is an uncommon cause of haematological and renal abnormalities in the postoperative period. It has a high mortality if untreated, and should be considered in the differential diagnosis of any postoperative patient with a low platelet count and anaemia, since prompt investigation and treatment is life-saving.

A Cardiac Sound Reproduction Apparatus for Improved Stethoscope Testing

Valvular heart disease is a significant problem. The primary case physician initially does assessment through auscultation. Accuracy in classification of sounds is suboptimal (20 to 40%). Lower frequencies of heart sounds are important in classification of murmurs associated with valvular heart disease. We find stethoscope sound intensity capture falls significantly at the 1500 Hz range and lower. Strategies to improve auscultation accuracy include improving stethoscope features or developing a device that, when used with the stethoscope, augments sound capturing abilities at lower frequencies. Testing necessitated development of a reliable (without significant intra-sound variation) cardiac sound reproduction device. A sound permeable contracting polymer when used with a stethoscope signficantly increases sound intensity captured in the 625 Hz to 1500 Hz range, when tested with a reliable cardiac sound reproduction device. We prepared an air-sealed device with an amplifier, four internal speakers capable of emitting high quality, low frequency sounds, and a listening pad. An existing electronic stethoscope with, and then without, a sound permeable contracting polymer captured three sounds (normal, innocent systolic murmur, pathological systolic murmur) five times per sound. The sounds were placed in computer files. FFTs were constructed. Sound intensity within the 625 Hz to 1400 Hz range, when the sound permeable contracting polymer is used with the electronic stethoscope, relatively improves, on average, approximately 11 dB, compared to sound captured with the same electronic stethoscope without the sound permeable contracting polymer. This difference is numerically statistically significant (p<0.001). Intra-sound variability testing (standard deviation) of FFTs was not significant. A sound permeable contracting polymer used with an electronic recording stethoscope significantly improves sound intensity in an important auscultation frequency range. Intra-sound testing variation was insignificant. A study is underway to demonstrate impact using an absolute reference point. However, as amplification within existing electronic stethoscopes is commercially available, potential variation in relative reference points may be overcome with existing amplification features on electronic stethoscopes, allowing improved capture of heart sounds within the 625 Hz to 1400 Hz range. Limitations include the need for human subject study. Further testing, including human subjects testing is needed prior to application for FDA approval. FDA approval is needed before any use on humans. The methodology should not be utilized clinically without FDA approval.

Variable Self-Optimizing Cochlear Model for Heart Murmur Detection/Classification

Accurate detection and classification of heart murmurs by auscultation is suboptimal and not always definitive. The murmur information perceived by the physician brain is the combined effect of both patient's (human) heart and the physician's ear. The information containing the murmur characterization which is retrieved by the human brain resides in the electrical signal coming out of the cochlea. For the very reasons described here, cochlea-like processing has been successfully applied to multiple speech recognition related technologies. This had not, before our prior work, been applied to human heart murmur analysis. Our prior research consisted of three steps: (1) capturing heart sounds, (2) processing the sounds using a cochlea-like filter, and then, (3) classifying each sound as being normal or a murmur using an artificial neural network (ANN). Previously in our research, we used a static cochlea-like filter model in step 2 as described above, which resulted a significant improvement in terms of accuracy of heart murmur classification. Our cochlear filter analysis helped identify information-rich frequency segments in human heart sound. We want to advance the cochlear filter model from a static to a variable frequency selective model with feedback from ANN for better optimization of the heart murmur classification. The heart sounds will be processed in ways more closely replicating the human cochlea than the static cochlear filter. A variable self optimizing cochlear filter will better reproduce the mechanism of the human cochlea in that it will contain a feedback system from ANN to cochlear processing to automatically select the most useful frequencies based upon a threshold mechanism filtering out those frequencies which do not contain significantly useful information about classification of heart murmur. The output of the sounds in the frequency range remaining (variable self-optimizing cochlear filtered sounds) may then be used by the neural network to make a final decision about murmur classification. Our hypothesis is that a variable self-optimizing cochlear filter will significantly improve the accuracy in classification of heart sounds as normal or murmur when compared to a static cochlear filter. Using this approach, we plan to develop an AI based system which will classify heart sounds with a success rate significantly better than the static cochlear filter previously developed.

Heart Murmur Detection∕Classification System Using Cochlea-Like Pre-Processing

According to the most recent report of American Heart Association (AHA), heart disease, stroke and other cardiovascular diseases continue to remain not only the no.1 killer of Americans but also a major cause of permanent disability among American workers. Recently, many research efforts have been carried out to apply artificial intelligence (AI) to auscultation based method for rigorous detection/classification of heart murmurs but accuracy rates are not always high. All of the proposed AI techniques rely on converting the heart sound to an electrical signal and processing that signal to optimize the AI for murmur detection and classification. However, all these techniques fail to recognize that the electrical signal coming out of the cochlea is very different than the electrical signal coming out of the microphone or any other electrical sensor which is commonly used for converting heart sound to electrical signal. In this research paper, we want to take a novel approach to pre-process the electrical heart sound signal before it goes to AI for murmur detection/classification by altering the electrical signal in a similar way as is done by the human cochlea before sending the signals to the brain. Our hypothesis is that cochlea like pre-processing will change the spectral contents of the heart sound signal to enhance the murmur information which can then be efficiently detected and classified by AI circuitry. Using this approach, we plan to develop an AI based system for heart murmur classification/ detection with success rate comparable to that of an expert cardiologist.

Hepatitis C virus infection among injecting drug users in Scotland: a review of prevalence and incidence data and the methods used to generate them

It is estimated that of 50,000 persons in Scotland (1% of the county's population), infected with the hepatitis C virus (HCV), around 90% injected drugs. This paper reviews data on the prevalence and incidence of HCV, and the methods used to generate such information, among injecting drug users (IDUs), in Scotland. The prevalence estimate for HCV among IDUs in Scotland as a whole (44% in 2000), is comparable with those observed in many European countries. Incidence rates ranged from 11.9 to 28.4/100 person-years. The data have shaped policy to prevent infection among IDUs and have informed predictions of the number of HCV-infected IDUs who will likely progress to, and require treatment and care for, severe HCV-related liver disease. Although harm reduction interventions, in particular needle and syringe exchanges and methadone maintenance therapy, reduced the transmission of HCV among IDUs during the early to mid-1990s, incidence in many parts of the country remains high. The prevention of HCV among IDUs continues to be one of Scotland's major public health challenges.

Prolonged bradycardia after secondary orbital implant

A patient who suffered a 36 hour symptomatic bradycardia following secondary orbital implant is described. The possible causes and implications are discussed.

Dendritic cells: the bare bones of immunity

Dendritic cells are specialized antigen-presenting cells, critical for initiating and regulating immune responses. Two new studies demonstrate the importance of coordinated cytoskeletal regulation for their normal function.

Cell-free plasma DNA as a prognostic marker in intensive treatment unit patients

Recent evidence suggests that cell-free plasma DNA has potential use as a prognostic marker in many clinical settings. The aim of the present study was to evaluate the prognostic role of cell-free plasma DNA in the prediction of clinical outcome in intensive treatment unit (ITU) patients. Cell-free plasma DNA was measured by real-time polymerase chain reaction assay for the beta-globin gene and SOFA score, APACHE II score, CRP concentrations, and clinical outcome (duration of stay, ventilation time, and mortality) were noted in 94 patients on admission to the ITU. The median plasma DNA concentration in ITU patients was 5493 GE/mL and this was significantly (P <0.001) higher than the DNA concentration in healthy subjects (1970 GE/mL). DNA concentration demonstrated a significant correlation with serum C-reactive protein (CRP) (r = 0.363) concentration and Sepsis-related Organ Failure Assessment (SOFA) (r = 0.360) score (P <0.001 for both by Pearson correlation) but not with Acute Physiology And Chronic Health Evaluation (APACHE II) score. Patients on ventilation had significantly higher DNA concentrations compared to nonventilated patients (7362 GE/mL versus 4479 GE/mL; P = 0.004). The median DNA concentration in nonsurvivors was 9148 GE/mL, and this was 2.3-fold greater than that in survivors (3921 GE/ml, P <0.001). ROC analysis of the data indicated a sensitivity of 85% and a specificity of 80% when DNA concentration of 6109 GE/mL was taken as a predictor of death. The data suggest that cell-free plasma DNA concentration is potentially useful as a prognostic marker in ITU patients.

A randomised controlled trial of cytological surveillance versus patient choice between surveillance and colposcopy in managing mildly abnormal cervical smears

OBJECTIVE

To determine whether choice of colposcopy or six month cytological surveillance would be beneficial to women with mildly abnormal smears when compared with the national policy of six months surveillance in terms of psychological morbidity.

DESIGN

A randomised trial based on the Zelen design.

SETTING

A hospital-based research clinic.

POPULATION

Four hundred and seventy-six women who had had a recurrent borderline or mildly dyskaryotic smear on routine cervical screening in primary care.

METHODS

Women were randomised either to six months cytological surveillance or to make a choice between that or colposcopy and were followed up for 1 year.

MAIN OUTCOME MEASURES

The primary outcome measure was caseness (score >or=4) on the General Health Questionnaire at 12 months follow up. Other measures were the Spielberger State and Trait scores, default rates and cytology/colposcopy outcomes.

RESULTS

There was no significant difference between the arms for General Health Questionnaire (GHQ) scores and Spielberger State and Trait at 12 months. There was a significant reduction in psychometric morbidity between baseline and 12 months in both arms. Overall rates of default from the protocol were the same in both arms, but default that led to uncertain ascertainment of cervical pathology was greater in the no-choice arm.

CONCLUSIONS

This trial indicates that having choice did not impact favourably or harmfully on anxiety or feelings of wellbeing. If a patient is anxious, allowing the patient to choose immediate colposcopy may be preferable because it will improve ascertainment of underlying disease in a group who are more likely to default.

Establishment of a database of diagnosed HCV-infected persons in Scotland

To provide a comprehensive understanding of the epidemiology of hepatitis C virus (HCV) infection in Scotland, a database of all persons known to have been infected with HCV in Scotland was established. Non-identifying data, held on the computers and requests forms in Scotland's principal and confirmatory HCV testing laboratories, were entered onto a National Database at the Scottish Centre for Infection and Environmental Health. As at December 2001, records from 13,519 persons in Scotland known to have been infected with HCV had been entered on to the database (one in 378 of Scotland's population). Of the 13,519, 69% were male and 90% of the 9,092 for whom risk factor information was available had injected drugs; 37% were from Greater Glasgow. Fifty-six per cent of the 13,519 were diagnosed between 1998 and 2001; 1,727 (23%) of the new diagnoses from 1998 to 2001 were aged under 25 years. The data provide an insight into the epidemiology of HCV infection in Scotland. They support other data, which indicate that the current major risk factor for HCV in the country is injecting drug use.

MIGRATION, LEAKAGE AND SEEPAGE CHARACTERISTICS OF THE OFFSHORE CANNING BASIN AND NORTHERN CARNARVON BASIN: IMPLICATIONS FOR HYDROCARBON PROSPECTIVITY

RadarSat and ERS Synthetic Aperture Radar (SAR) satellite data have been used for oil slick mapping as part of a systematic interpretative study of the offshore Canning Basin, as well as part of the northern Carnarvon Basin, extending from the inner shelf to the abyssal plain. These seepage data have been integrated with regional geological data, more than 12,000 km of reprocessed Airborne Laser Fluorosensor (ALF) survey data, seismic DHI indicators, water column geochemical sniffer data, potential field data, earthquake data and 2D Petromod basin modelling, to provide new insights into the region’s petroleum prospectivity and key exploration risk factors.From a prospectivity viewpoint, this study has highlighted several areas and processes. Firstly, it is clear that overpressure in the region is principally controlled by the thickness of the Tertiary carbonate wedge and we predict that overpressure may be present in parts of the deeper water Canning Basin. Secondly, the offshore Canning Basin contains a relatively low density of SAR-mapped oil slicks, though this appears to be due to a combination of factors, namely a paucity of vertical conduits for leakage, a predominantly condensate-prone charge and a small slick size.Significantly, several as-yet untested areas emerge from our observations. In the offshore Canning Basin, a 'window' exists in about 1,500–2,500 m of water, where the Triassic source rocks are particularly well placed for liquids generation. Morever, a large area in a radius some 20–80 km outboard of the Bedout High, also appears to have significant untested liquids potential, with respect to sourcing from the Triassic. The shallow section through this region contains a vast area with abundant seismically mapped gas chimneys and other seepage indicators, supporting the conclusions from the remote sensing and basin modelling of significant hydrocarbon charge in this region. Finally, the study indicates that liquids have been generated within the Palaeozoic section of the Bedout Sub-basin.

Prevalence of hepatitis C among injectors in Scotland 1989-2000: declining trends among young injectors halt in the late 1990s

We previously reported a continual decline in anti-HCV prevalence among young injectors from Glasgow and Lothian between 1990 and 1997. The original study was extended to ascertain if the anti-HCV prevalence among injectors from Glasgow, Lothian, Tayside and Grampian had changed since 1997. Residual sera from injectors who had undergone attributable anti-HIV testing were tested anonymously for anti-HCV. In all four regions, no significant changes in prevalence were found among those aged < 25 years during the late 1990s (Glasgow 1997-9/00: 43%-41%; Lothian 1997-9: 13%-17%; Tayside 1997-9: 45%-35%; Grampian 1996-9: 28%-29%). Among those aged > or = 25 years, significant decreases in prevalence were only observed in Glasgow (1997-9/00: 79%-72%, P = 0.03) and Lothian (1997-9: 54%-45%, P = 0.05). The findings highlight that existing harm reduction measures, acknowledged as having helped to reduce the spread of HCV, are not sufficient to bring this epidemic under control and reduce transmission to sporadic levels.

Trends in HCV prevalence among injecting drug users in Glasgow and Edinburgh during the era of needle/syringe exchange

In 1998, we reported that anti-HCV prevalence among injectors from Glasgow had declined between 1990 and 1995. We set out to ascertain if the anti-HCV prevalence among injectors from Edinburgh had declined similarly during this period and if there had been any trend in prevalence among injectors from both cities since 1995. Residual sera from both cities' injecting drug users who had undergone named HIV testing were identified, linked to age band and gender information and tested anonymously for anti-HCV. Among Edinburgh's injectors, significant (p < 0.0001) decreases in anti-HCV prevalence from 69% (1989/90) to 13% (1997) and from 80% (1989/90) to 54% (1997) were seen in those aged < 25 y and > or = 25 y, respectively. Among Glasgow's injectors, a significant (p < 0.0001) decrease in prevalence from 91% (1990) to 43% (1997) was seen only among those aged < 25 y. Of both cities' 15-19 y olds, sampled during 1995-97, 17% (24/139) were anti-HCV-positive. The findings suggest that the incidence of HCV among young injectors continued to decrease during the 1990s--the era of needle/syringe exchange and other interventions--but is still too high. Further investigative and preventive work is required.