Conventional versus ultra-low dose computed tomogram in Crohn's disease: Do morphomics correlate with clinical data?

BACKGROUND

Cross-sectional study to assess the body composition of patients with Crohn's disease (CD) on standard (SDCT) and low dose CT (LDCT) protocols for the abdomen and pelvis (CTAP). We aimed to assess if a low dose CT protocol reconstructed with model-based iterative reconstruction (IR) could evaluate body morphometric data comparable to standard dose examination.

METHODS

The CTAP images of 49 patients who underwent a low dose CT scan (20% of standard dose) and a second at standard dose minus 20% were assessed retrospectively. Images were collected from the PACS system, deidentified and analysed using a web-based semi-automated threshold-based segmentation tool (CoreSlicer), capable of identifying tissue type based on differences in attenuation co-efficient. The cross-sectional area (CSA) and Hounsfield units (HU) of each tissue was recorded.

RESULTS

Muscle and fat CSA is well preserved on comparing these derived metrics from low dose and standard dose CT scans of abdomen and pelvic in CD ((LDCT:SDCT mean CSA (cm²); Psoas muscle - 29.00:28.67, total lumbar muscle - 127.45:125.55, visceral fat- 110.44:114.16, subcutaneous fat - 250.88:255.05)). A fixed difference exists when assessing the attenuation of muscle, with higher attenuation on the low dose protocol (LDCT:SDCT mean attenuation (HU); Psoas muscle - 61.67:52.25, total lumbar muscle - 49.29:41.20).

CONCLUSION

We found comparable CSA across all tissues (muscle and fat) on both protocols with a strong positive correlation. A marginally lower muscle attenuation suggestive of less dense muscle was highlighted on SDCT. This study augments previous studies suggesting that comparable and reliable morphomic data may be generated from low dose and standard dose CT images.

IMPLICATIONS FOR PRACTICE

Threshold-based segmental tools can be used to quantify body morphomics on standard and low dose computed tomogram protocols.

Understanding the Educational Support and Psychosocial Needs of Parents and Adolescents With Kawasaki's Disease and Coronary Artery Aneurysms

INTRODUCTION

Kawasaki disease (KD) with coronary artery aneurysms (complex KD) presents relentless challenges for families. Psychosocial experiences and needs were explored.

METHOD

A descriptive, exploratory study of adolescents and parents using a needs survey and psychosocial instruments (anxiety, depression, and functional impairment).

RESULTS

Fifty-one parents and 38 adolescents participated. Predominant interests were for information sheets, newsletters, Web sites, and phone applications. Gaps in disease-specific knowledge and awareness of coronary artery aneurysms between parents and adolescents were identified. Psychosocial concerns for adolescents included symptoms of anxiety (22%), depression (13%), and functional impairment (22%). Multivariable analyses indicated higher depression scores associated with longer travel distance from specialists (p = .04). Parent-reported social concerns for their adolescent were associated with higher anxiety (p = .005) and functional impairment (p = .005). Written commentary complemented the findings.

DISCUSSION

Care protocols require psychosocial assessment/referral and the use of virtual platforms. The groundwork was laid for developing patient and family-centered strategies.

Associations between the spatiotemporal distribution of Kawasaki disease and environmental factors: evidence supporting a multifactorial etiologic model

The etiology of Kawasaki Disease (KD), the most common cause of acquired heart disease in children in developed countries, remains elusive, but could be multifactorial in nature as suggested by the numerous environmental and infectious exposures that have previously been linked to its epidemiology. There is still a lack of a comprehensive model describing these complex associations. We present a Bayesian disease model that provides insight in the spatiotemporal distribution of KD in Canada from 2004 to 2017. The disease model including environmental factors had improved Watanabe-Akaike information criterion (WAIC) compared to the base model which included only spatiotemporal and demographic effects and had excellent performance in recapitulating the spatiotemporal distribution of KD in Canada (98% and 86% spatial and temporal correlations, respectively). The model suggests an association between the distribution of KD and population composition, weather-related factors, aeroallergen exposure, pollution, atmospheric concentration of spores and algae, and the incidence of healthcare encounters for bacterial pneumonia or viral intestinal infections. This model could be the basis of a hypothetical data-driven framework for the spatiotemporal distribution of KD. It also generates novel hypotheses about the etiology of KD, and provides a basis for the future development of a predictive and surveillance model.

Characterization of Post-Thrombotic Syndrome in Children with Cardiac Disease

OBJECTIVE

To assess the validity of existing clinical scales assessing the presence of physical and functional abnormalities for diagnosing post-thrombotic syndrome (PTS) in children, including specific evaluation of use in children with congenital heart disease (CHD).

STUDY DESIGN

One hundred children aged >2 years (average age, 6 years), including 33 with CHD and previously proven extremity deep vein thrombosis (DVT), 37 with CHD and no previous DVT, and 30 healthy siblings, were blindly assessed for PTS using the modified Villalta Scale (MVS). All patients aged <6 years underwent neurodevelopmental testing and an age-appropriate quality of life assessment.

RESULTS

The MVS identified mild PTS in 20 children and moderate PTS in 1 child (including 14 of 33 [42%] in the CHD/DVT group, 5 of 37 [14%] in the CHD/no DVT group, and 2 of 30 controls [7%]). The diagnosis of PTS was confirmed clinically in 14 patients, all of whom had previous thrombosis and 1 of whom was MVS-negative. MVS had an accuracy of 91% and performed reasonably well as a screening tool but poorly as a diagnostic tool. MVS reliability was acceptable. Children with PTS had similar quality of life as those without PTS but had higher rates of neurodevelopmental delays in gross motor skills (70% vs 24%; P = .02) and problem-solving indicators (60% vs 15%; P = .008).

CONCLUSIONS

Using the MVS scale for PTS screening in children with CHD is feasible and reliable, and the scale has good correlation with a clinical diagnosis of PTS despite a high prevalence of false-positive findings. Further research is needed to determine the clinical relevance of PTS in this population.

A Multicentre Study of Thromboprophylaxis in Pregnancy

Venous thromboembolism (VTE) is a leading cause of maternal mortality. The risk increases with increasing maternal age, mode of delivery and medical co-morbidities. Thromboprophylaxis with low molecular weight heparin (LMWH) has been shown to be both safe and efficacious. The aim of this study was to prospectively investigate the incidence of maternal risk factors in pregnant women admitted to hospital, to calculate their VTE risk status and to investigate if they were receiving appropriate thromboprophylaxis. All patients admitted to the participating hospitals on the day of investigation were assessed for risk of VTE on the basis of hospital chart review. Five Hundred and forty women were recruited from 16 hospitals. Almost 32% (31.7%) were receiving thromboprophylaxis with LMWH. Just under 80% of patients were on the correct thromboprophylaxis strategy as defined by the RCOG guideline but 49% were under-dosed. The odds of receiving appropriate thromboprophylaxis were significantly increased if the woman was >35 years 0or with parity>3.

Hospital Acquired Thrombosis (HAT) Prevention in an Acute Hospital; A Single Centre Cross-Sectional Study

Evidence based guidelines are effective in reducing incidence of venous thromboembolism (VTE) which is associated with morbidly, mortality and economic burden. This study aimed to identify the proportion of inpatients who had a VTE risk assessment (RA) performed and who received thromboprophylaxis (TP), in Cork University Hospital. There was no structured RA tool at the time; information was obtained from medical and drug charts to ascertain if a RA was performed. Patients were then RA by researchers and stratified as per NICE guidelines and the proportion who received TP was calculated. One thousand and nineteen inpatients were screened. Risk was documented in 24% of cases. TP was prescribed in 43.2% of inpatients. Following application of a RA tool >80% were at high risk of VTE with low risk of bleeding with TP prescription in 46.3% of inpatients. A national collaborative effort should be encouraged to develop a standardized approach for safe RA of inpatients and prescription of TP for prevention of HAT.

Incidence of Hospital Acquired Thrombosis (HAT) in a Tertiary Care Hospital

Venous thromboembolism (VTE) is a major cause of preventable morbidity and mortality in hospitalized patients. In spite of guidelines, VTE prophylaxis continues to be underutilised, and hospital acquired thrombosis (HAT) continues to be a problem. This study was conducted to estimate the incidence of HAT in a tertiary referral centre and to examine whether VTE risk assessment and thromboprophylaxis (TP) were implemented. Patients 18 years and above, with a radiologically-confirmed acute VTE during the study period of 15 weeks were included. Acute VTE was diagnosed in 100 patients and HAT was diagnosed in 48. There were 12,024 admissions over the study period, therefore the incidence of HAT was 0.4%. TP was prescribed in only 35% of patients, and 65% did not receive any or appropriate TP. Hospitals without active implementation of a formal risk assessment tool and TP policy are likely to continue to have increased incidence of HAT.

Venous Thromboembolism - Risk Assessment Tool and Thromboprophylaxis Policy: A National Survey

Venous Thromboembolic (VTE) events in hospitalised patients are associated with significant mortality and morbidity and a major economic burden on the health service. It is well established in the literature that active implementation of a mandatory risk assessment tool and thromboprophylaxis policy reduces the incidence of hospital associated thrombosis (HAT). This study examines the utilization of a VTE risk assessment tool and thromboprophylaxis (TP) policy in Irish hospitals that manage acute admissions. A national survey was distributed to forty acute hospitals throughout Ireland. The response rate was 78% (31/40). The results showed that only 26% (n=8/31) of acute hospitals in Ireland have a local implemented TP policy. Six (75%) of these eight had a risk assessment tool in conjunction with the TP policy. All respondents who did not report to have a TP policy and risk assessment tool agreed that they should implement VTE prevention policy at their hospital. Based on the data from this survey and evidence from the effectiveness of the VTE prevention programme introduced in the United Kingdom, there is a need for a national risk assessment and thromboprophylaxis policy in Ireland. This change in practice would have the potential to prevent or reduce the morbidity and mortality associated with hospital acquired thrombosis.

Constraints on oceanic methane emissions west of Svalbard from atmospheric in situ measurements and Lagrangian transport modeling

Methane stored in seabed reservoirs such as methane hydrates can reach the atmosphere in the form of bubbles or dissolved in water. Hydrates could destabilize with rising temperature further increasing greenhouse gas emissions in a warming climate. To assess the impact of oceanic emissions from the area west of Svalbard, where methane hydrates are abundant, we used measurements collected with a research aircraft (Facility for Airborne Atmospheric Measurements) and a ship (Helmer Hansen) during the Summer 2014 and for Zeppelin Observatory for the full year. We present a model-supported analysis of the atmospheric CH₄ mixing ratios measured by the different platforms. To address uncertainty about where CH₄ emissions actually occur, we explored three scenarios: areas with known seeps, a hydrate stability model, and an ocean depth criterion. We then used a budget analysis and a Lagrangian particle dispersion model to compare measurements taken upwind and downwind of the potential CH₄ emission areas. We found small differences between the CH₄ mixing ratios measured upwind and downwind of the potential emission areas during the campaign. By taking into account measurement and sampling uncertainties and by determining the sensitivity of the measured mixing ratios to potential oceanic emissions, we provide upper limits for the CH₄ fluxes. The CH₄ flux during the campaign was small, with an upper limit of 2.5 nmol m^-2 s^-1 in the stability model scenario. The Zeppelin Observatory data for 2014 suggest CH₄ fluxes from the Svalbard continental platform below 0.2 Tg yr^-1. All estimates are in the lower range of values previously reported.

Thromboprophylaxis in myeloma: what is happening outside of clinical trials?

Patients with myeloma are at high risk of venous thromboembolism (VTE). There is no consensus about what agent to use or what haematologists are doing in clinical practice. A survey was sent to haematologists treating patients with myeloma in Ireland. 32/45 (71%) responded. 13/28 (46%) felt that VTE affected < 5% of patients. However, 8/28 (29%) felt it affected 10-19%. Thromboprophylaxis was most commonly used in patients on lenalidomide; 25/28 (89%) and thalidomide; 23/28 (82%). 23/28 (82%) used LMWH and 20/28 (71%) used aspirin either very frequently or frequently. 3/28 (11%) had used dabigatran/rivaroxaban despite there being little evidence to support their use. Efficacy was the most important factor in choosing an agent for 25/28 (89%). Bleeding was not felt to be an issue 15/29 (52%) were not using thromboprophylaxis guidelines. This survey demonstrated wide variation in the beliefs and practices regarding the burden of VTE in patients with myeloma and the need for thromboprophylaxis.

Implementation of thromboprophylaxis guidelines

Venous thromboembolism (VTE) remains one of the leading direct causes of maternal death. Risk factors for VTE and prophylaxis guidelines have been highlighted by the Royal College of Obstetricians and Gynaecologists (RCOG). A cross sectional study was completed in Cork University Maternity Hospital (CUMH) to determine pattern of VTE risk and compliance with 2004 RCOG guidelines. 364 women's charts were reviewed. Forty percent (n = 145) were at risk for VTE, 69% (n = 100) of these received thromboprophylaxis but only 54% (n = 54) received the correct weight adjusted dose. Three of four morbidly obese women in this study received recommended thromboprophylaxis but none at the appropriate dose. Only 67% (n = 245) had a recorded body mass index (BMI). Increased BMI is a significant risk factor for VTE and should be measured and recorded at the booking visit. Awareness of the risks for VTE and the need for appropriate dosing should be improved.

Complications following pancreatic transplantations: imaging features

Whole organ vascularized pancreatic transplant is a recognized treatment for diabetes and is increasingly being performed worldwide. The procedure itself is complex and is associated with significant mortality and morbidity. Despite improvements in surgical techniques, postoperative complications of pancreatic transplantation are still common and include graft rejection, pancreatitis, peripancreatic fluid collections, exocrine leaks, vascular thrombosis, and hemorrhage. In this pictorial essay, we review clinical presentation and imaging features of these complications. We also briefly discuss technique and complications of islet cell transplants.

In vitro activity of Inula helenium against clinical Staphylococcus aureus strains including MRSA

The present study aims to investigate the bactericidal activity (specifically antistaphylococcal) of Inula helenium. The antimicrobial activity of the extract is tested against 200 clinically significant Irish Staphylococcus aureus isolates consisting of methicillin-resistant (MRSA) and -sensitive (MSSA) S. aureus using a drop test method and a microbroth dilution method. The antibacterial effect is evaluated by measuring the area of the inhibition zone against the isolates. Results proved I. helenium to be 100% effective against the 200 staphylococci tested, with 93% of isolates falling within the ++ and +++ groups. The minimum bactericidal concentration of I. helenium was examined on a subset of isolates and values ranged from 0.9 mg/mL to 9.0 mg/mL. The extract was equally effective against antibiotic-resistant and -sensitive strains. This plant therefore possesses compounds with potent antistaphylococcal properties, which in the future could be used to complement infection control policies and prevent staphylococcal infection and carriage. This research supports other studies wherein herbal plants exhibiting medicinal properties are being examined to overcome the problems of antibiotic resistance and to offer alternatives in the treatment and control of infectious diseases.

Randomized controlled trial of supervised patient self-testing of warfarin therapy using an internet-based expert system

BACKGROUND

Increased frequency of prothrombin time testing, facilitated by patient self-testing (PST) of the International Normalized Ratio (INR) can improve the clinical outcomes of oral anticoagulation therapy (OAT). However, oversight of this type of management is often difficult and time-consuming for healthcare professionals. This study reports the first randomized controlled trial of an automated direct-to-patient expert system, enabling remote and effective management of patients on OAT.

METHODS

A prospective, randomized controlled cross-over study was performed to test the hypothesis that supervised PST using an internet-based, direct-to-patient expert system could provide improved anticoagulation control as compared with that provided by an anticoagulation management service (AMS). During the 6 months of supervised PST, patients measured their INR at home using a portable meter and entered this result, along with other information, onto the internet web page. Patients received instant feedback from the system as to what dose to take and when the next test was due. During the routine care arm, patients attended the AMS at least every 4-6 weeks and were dosed by the anticoagulation pharmacist or physician. The primary outcome variable was the difference in the time in therapeutic range (TTR) between both arms.

RESULTS

One hundred and sixty-two patients were enrolled (male 61.6%, mean age 58.7 years), and 132 patients (81.5%) completed both arms. TTR was significantly higher during PST management than during AMS management (median TTR 74% vs 58.6%; z=5.67, P < 0.001).

CONCLUSIONS

The use of an internet-based, direct-to-patient expert system for the management of PST improves the control of OAT as compared with AMS management.

Utilization of HIV point-of-care testing clinics in general practice and genitourinary medicine services in south-east London

We compared the utilization of HIV point-of-care testing (POCT) clinics in a general practice and a genitourinary (GU) medicine service. Retrospective case-note review of patients attending the general practice HIV POCT clinic from February 2005 to July 2007 was undertaken. Those attending the GU medicine service over the same period were used as a comparator group. HIV POCT clinics in general practice when compared with GU medicine services were significantly more likely to be utilized by those of Black ethnicity (Black African 61/370 [16.5%] vs. 107/1231 [8.7%], P < 0.001; Black Caribbean 19/370 [5.1%] vs. 11/1231 [0.9%], P < 0.001 and Black Other 20/370 [5.4%] vs. 26/1231 [2.1%], P = 0.001, respectively). Fewer men who have sex with men attended for HIV POCT in general practice than in GU medicine; 82/238 (34.5%) vs. 337/816 (41.3%), P = 0.058. We have demonstrated that HIV POCT clinics in primary care and GU medicine attract different 'at-risk' groups and provide increased opportunity for testing.

The reliability of point-of-care prothrombin time testing. A comparison of CoaguChek S and XS INR measurements with hospital laboratory monitoring

The development of point-of-care (POC) testing devices enables patients to test their own international normalized ratio (INR) at home. However, previous studies have shown that when compared with clinical laboratory values, statistically significant differences may occur between the two methods of INR measurement. The aim of this study was to evaluate the accuracy of the CoaguChek S and XS POC meters relative to clinical laboratory measurements. As part of a randomized, crossover patient self-testing (PST) study at Cork University Hospital, patients were randomized to 6 months PST or 6 months routine care by the anticoagulation management service. During the PST arm of the study, patients measured their INR at home using the CoaguChek S or XS POC meter. External quality control was performed at enrollment, 2 months and 4 months by comparing the POC measured INR with the laboratory determined value. One hundred and fifty-one patients provided 673 paired samples. Good correlation was shown between the two methods of determination (r = 0.91), however, statistically significant differences did occur. A Bland-Altman plot illustrated good agreement of INR values between 2.0 and 3.5 INR units but there was increasing disagreement as the INR rose above 3.5. Eighty-seven per cent of all dual measurements were within the recommended 0.5 INR units of each other. This study adds to the growing evidence that POC testing is a reliable and safe alternative to hospital laboratory monitoring but highlights the importance of external quality control when these devices are used for monitoring oral anticoagulation.

Characterization of the three Arabidopsis thaliana RAD21 cohesins reveals differential responses to ionizing radiation

The RAD21/REC8 gene family has been implicated in sister chromatid cohesion and DNA repair in several organisms. Unlike most eukaryotes, Arabidopsis thaliana has three RAD21 gene homologues, and their cloning and characterization are reported here. All three genes, AtRAD21.1, AtRAD21.2, and AtRAD21.3, are expressed in tissues rich in cells undergoing cell division, and AtRAD21.3 shows the highest relative level of expression. An increase in steady-state levels of AtRAD21.1 transcript was also observed, specifically after the induction of DNA damage. Phenotypic analysis of the atrad21.1 and atrad21.3 mutants revealed that neither of the single mutants was lethal, probably due to the redundancy in function of the AtRAD21 genes. However, AtRAD21.1 plays a critical role in recovery from DNA damage during seed imbibition, prior to germination, as atrad21.1 mutant seeds are hypersensitive to radiation damage.

Genotyping of B and non-B subtypes of human immunodeficiency virus type 1

Current HIV-1 genotyping assays were developed using subtype B viruses prevalent in Western countries. It is not clear whether these assays are appropriate for use among African patients, who are likely to be infected with non-B subtypes. We evaluated the Bayer TRUGENE HIV-1 genotyping (TG) assay using prospectively collected samples from HIV-1-infected individuals who acquired infection in either sub-Saharan Africa or the West (Europe, North America, and Australia). Plasma samples from 208 individuals with an HIV-1 viral load of >1,000 copies/ml were tested using version 1 primers supplied with the TG assay. If these failed, an alternative primer set version 1.5 was used. Of the 208 individuals, the likely origin of infection was Africa (n = 104), Western (n = 87) and "Others" (i.e., all other geographic locations or origin not certain; n = 17). Among the three groups, the version 1 primers were successful in 85 (82%), 77 (89%), and 13 (76%) individuals, respectively (P = 0.1). Of the remaining 32 samples, 30 were successfully amplified by using the version 1.5 primers. HIV-1 subtypes deduced from the reverse transcriptase sequences correlated with the likely origin of infection: Africa (28A, 3B, 33C, 13D, 6G, 4J, 2K, 5CRF01_AE, and 10CRF02_AG), Western (86B and 1K), and Others (1A and 16B). The success of the version 1 primers correlated with viral load (P < 0.014) and not with HIV-1 subtypes. A protocol based on version 1 primers, followed by 1.5 primers, was successful in sequencing 99% of the samples in this cohort.

Therapeutic, prophylactic, and preresection applications of laparoscopic gastric and biliary bypass for patients with periampullary malignancy

BACKGROUND

Laparoscopic bypass surgery for the palliation of gastric and biliary obstruction is associated with a rapid recovery. This study aimed to extend its application to other aspects in the management of patients with periampullary cancer.

METHODS

Between 2001 and 2004, 21 patients (median age, 68 years) underwent laparoscopic gastric (n = 8), biliary (n = 5), and combined gastric and biliary (n = 8) bypass. In addition to its therapeutic role (n = 12), indications included a concomitant prophylactic gastric (n = 3) and biliary (n = 2) bypass as well as pre- 1 Whipple's relief of deep jaundice at the time of staging laparoscopy (n = 3). Construction of the biliary bypass to the gallbladder (n = 11) or bile duct (n = 2) was based on preoperative imaging.

RESULTS

All procedures were completed laparoscopically. The median operating times for gastric, biliary, and combined bypass were 75, 60, and 130 min, respectively. The addition of a prophylactic bypass did not significantly prolong the operating time, as compared with a single therapeutic bypass. One patient died postoperatively of aspiration pneumonia. The postoperative hospital stay (median, 4 days) was not significantly influenced by the type of bypass. No recurrence of or new obstructive symptoms developed during the follow-up period after a therapeutic or prophylactic bypass.

CONCLUSIONS

Applications of laparoscopic gastric and biliary bypass can safely be expanded to include a prophylactic role and preresection relief of obstructive jaundice. Prophylactic bypass surgery does not prolong operating time or hospital stay significantly and prevents future onset of obstructive symptoms.

Pilot scheme for performance assessment of HIV-1 genotypic resistance testing in the UK

HIV-1 drug susceptibility testing by genotypic methods is now widespread in the UK and it is thus important to determine the reproducibility of such investigations. A pilot study was carried out to determine the reproducibility between laboratories of genotypic testing by nucleotide sequencing of patient samples, and to compare the interpretations of the results provided to the clinicians. Samples were distributed between the participating laboratories. Eight laboratories, using three different methods, sequenced four samples. Nucleotide sequence and reports were collated and compared by one laboratory. Where sequencing data were obtained > 99% concordance was observed for nucleotide designations. No discordances in nucleotide sequencing were found in positions associated with drug resistance. However, there were considerable differences between the laboratories in the interpretation of some of the mutations with respect to their effect on drug susceptibility. This study emphasises the variability in the available interpretation systems, and the importance of joint laboratory-clinical discussion in making decisions about treatment options.

Laparoscopic reduction of an ileoileal intussusception and resection of an inverted Meckel's diverticulum in an adult

Intussusception occurs commonly in children, but rarely is observed in adults. Whereas the hydrostatic pressure of a contrast enema often proves diagnostic as well as therapeutic in infants and children, resection usually is required for an underlying bowel pathology in older children and adults. Conventionally, the resection is accomplished at laparotomy. We report the case of a 20-year-old woman who presented with diarrhea and vomiting of 1 week duration. She was found unexpectedly to have intussusception on abdominal ultrasonography. The intussusception was laparoscopically reduced, and a segment of the middle small bowel that harbored an inverted Meckel's diverticulum was resected laparoscopically, after which an intracorporeal anastomosis was fashioned. The ileus resolved on postoperative day 4, and the patient was discharged from hospital on postoperative day 5. The role of the laparoscopic approach in the management of intussusception is discussed.

Guidelines for the management of HIV infection in pregnant women and the prevention of mother-to-child transmission

AIMS OF THE GUIDELINES: These guidelines, drawn up by a multidisciplinary group of clinicians and lay workers active in the management of pregnant women infected with HIV, aim to give up-to-date information on interventions to reduce the risk of mother to child transmission of the virus. The evidence on the use of interventions to prevent mother to child transmission of HIV has been graded according to the strength of the data as per the definitions of the US Agency for Health Care Policy and Research [1]. Weighted evidence on the use of combination antiretroviral therapy (ART) for the treatment of HIV infection per se is presented in the BHIVA guidelines for adults [2,3]. The highest level evidence (i.e. randomised controlled trials (RCTs) or large, well conducted meta-analyses) is only available for formula feeding, prelabour caesarean section and zidovudine monotherapy. The need to treat mothers for HIV infection has led to the widespread use of ART in pregnancy which in turn results in new questions such as how to deliver when the mother, on therapy, has no detectable plasma viraemia with the most sensitive assays. In addressing many common and/or difficult clinical scenarios in the absence of 'best evidence' the guidelines rely heavily on 'expert opinion'. Recommendations for management are given in the section on clinical scenarios, and summarized in Table 3. An expanded version of these guidelines with an appendix on safety and toxicity data is available on the BHIVA website http://www.bhiva.org. The authors are available to discuss individual cases.

Expression of glycine receptors in rat sensory neurons vs. HEK293 cells yields different functional properties

Many structure-function studies of the glycine receptor (GlyR), and other ligand-gated ion channels, use somatic cell lines or Xenopus oocytes as expression systems. Using a polyethylenimine-based technique, we transfected GlyR cDNA into primary cultures of rat dorsal root ganglion (DRG) neurons. We then compared the functional properties of wildtype and a mutant GlyR expressed in DRG neurons with HEK 293 cells. The glycine sensitivity of the wildtype GlyR was nearly identical for the two cell types. The mutant GlyR has an arginine for glutamine substitution at position 271 (R271Q), which results in low glycine sensitivity relative to wildtype receptors expressed in HEK cells. This point mutation is associated with startle disease (hyperekplexia) in humans. Mutant GlyR expression in DRG neurons resulted in a significantly lower glycine sensitivity than was seen in HEK cells. This supports the idea that neuron-specific post-translational modifications may be important for determining receptor function.

Effects of in vivo heregulin beta1 treatment in wild-type and ErbB gene-targeted mice depend on receptor levels and pregnancy

Mice heterozygous (+/-) for either heregulin (HRG), ErbB2, or ErbB3 were created by gene targeting, resulting in the loss of one functional gene copy and an associated decrease in targeted protein. We examined the in vivo activity of recombinant HRG peptide, rHRG beta1 (amino acids 177 to 241), in the three heterozygous mouse lines and in wild-type (WT) mice, both pregnant and nonpregnant. Nonpregnant WT and HRG(+/-) mice of both sexes were sensitive to rHRG beta1 treatment as evidenced by a high mortality rate associated with abdominal enlargement and parietal cell loss. However, pregnant WT mice and ErbB2 and ErbB3 heterozygous mice treated with rHRG beta1 were less affected, with significantly lower mortality rates and a less severe abdominal phenotype. Histological analysis revealed extensive breast ductal hyperplasia in females of all genotypes after rHRG beta1 treatment. Hyperplasia of other epithelial tissues such as the pancreas and intestine and the growth of cardiac nerve bundles were also observed, independent of sex.

Antiretroviral therapy for HIV-2 infected patients

OBJECTIVES

To evaluate clinical and RNA load response to antiretroviral therapy amongst patients infected with HIV-2 and to study the development of drug resistance.

METHODS

Seven HIV-2 seropositive patients were monitored with clinical examination, CD4 cell count and HIV-2 viral RNA load. Viruses from four subjects were genotyped and in vitro recovery of virus by co-cultivation with PBMCs and HVS T-cells was attempted. Viruses isolated from two subjects were assayed for phenotypic antiviral resistance. The main outcome measures were the relationship between disease stage, viral load, CD4 cell count, viral subtype and the clinical course of HIV-2 infection and the effect of combination antiretroviral therapy on disease progression, CD4 cell count, HIV-2 RNA viral load and drug resistance.

RESULTS

The median time of follow-up was 3 years (range 0-8 years). Three patients had AIDS, and one had symptomatic disease. Of the four patients genotyped, three were infected with HIV-2 subtype B and one with subtype A. Viraemia was detectable only at CD4 counts of less than 300 x 10(6)/ml. Two patients with high viral loads failed to respond to antiretroviral therapy although their treatment may not have been optimal. One developed in vitro phenotypic antiviral resistance. The genotype of this patient's viral reverse transcriptase is being analysed.

CONCLUSIONS

In contrast to HIV-1, HIV-2 RNA levels were often undetectable despite advanced disease and low CD4 cell counts. However, HIV-2 was clearly capable of causing CD4 cell depletion resulting in symptomatic disease. The principles of highly active antiretroviral therapy seem to apply to HIV-2 and suboptimal therapy may lead to drug resistance. The timing of therapy initiation, monitoring of response and the measurement of resistance remain unresolved issues and conclusions cannot be extrapolated from HIV-1.

Renal medullary carcinoma: sonographic, computed tomography, magnetic resonance and angiographic findings

Renal medullary carcinoma is a recently described, highly aggressive tumour, occurring predominantly in young patients of African descent with sickle cell trait (SCT). All have been metastatic at surgery. Surgery, radiotherapy and chemotherapy do not appear to alter the course of the disease. The survival time is very short. Presentation is usually with haematuria, abdominal pain and weight loss. Forty-nine patients have been reported from the USA, of these 47 were African/Americans. The reports have mostly appeared in pathology journals. On review of the imaging findings reported in the radiological journals, it becomes apparent that it is possible for a radiologist to suggest a specific diagnosis in the appropriate demographic and clinical setting. Here the first British patient of Afro-Caribbean decent in whom a pre-operative diagnosis was suggested on the imaging findings of a centrally located renal pelvic tumour, encasing the pelvis on a background of SCT in a 28-year-old is described. It is expected that a high index of suspicion in the appropriate clinical setting may lead to earlier diagnosis, treatment and survival of patients. The patient is alive and reasonably well 9 months after surgery. The full range of imaging findings in renal medullary carcinoma are described.