Characteristics of Gastroenteritis Outbreaks Investigated in Singapore: 2018-2021

There is a need to study the characteristics of outbreaks via Singapore's outbreak surveillance system to understand and identify the gaps in food safety for targeted policy interventions due to the increasing trend in gastroenteritis outbreaks and consequential increase in foodborne-related deaths and economic burden on public health systems worldwide. A total of 171 gastroenteritis outbreaks were investigated in Singapore from January 2018 to December 2021. This study analyzed the annual trend of investigated gastroenteritis outbreaks, the proportion of outbreaks by implicated sources of food, and the proportion of the type of pathogens identified from human cases, food samples, and environmental swabs collected from outbreak investigations. Among the foodborne gastroenteritis outbreaks (n = 121) investigated in Singapore, approximately 42.1% of the outbreaks had food prepared by caterers, 14.9% by restaurants, and 12.4% had food prepared by in-house kitchens. Clostridium perfringens and Salmonella were the most common causative pathogens in foodborne outbreaks throughout the analysis period. The food samples and environmental swabs collected were mostly detected for Bacillus cereus. Norovirus was the most common causative pathogen in non-foodborne outbreaks and was mainly attributable to preschools. This highlights the importance of monitoring and educating the catering industry and preschools to prevent future outbreaks.

Quantification of Pork, Chicken, Beef, and Sheep Contents in Meat Products Using Duplex Real-Time PCR

Accurate methods for meat speciation and quantification are essential for ensuring the supply of safe and wholesome meat and composite products with animal origins to negate the potential associated hazards, aid classification of consignments at the import control system, and thwart food fraud committed for financial gain. To better enhance meat safety control and combat food fraud, this study developed two duplex real-time polymerase chain reaction (real-time PCR) systems specifically designed for chicken, pork, sheep, and beef, using single-copy, chromosomally encoded, species-specific gene sequences to accurately measure the content of each meat type in meat products. DNA extracted from the raw and boiled reference materials prepared in varying proportions (ranging from 1% to 75%) were used in the development of the duplex assay to derive calibration factors to determine the meat content in different meat products. The method was further validated using proficiency test samples and market monitoring samples. Our findings showed that this method exhibits high specificity and sensitivity, with a significant accuracy range of 0.14% to 24.07% in quantifying the four meat types in both raw and processed meat products. Validation results further confirmed the effectiveness of our method in accurately quantifying meat content. Thus, we have demonstrated the duplex qPCR assays as promising approaches for implementation in routine analysis to strengthen meat safety control systems and combat meat fraud, thereby safeguarding consumer health and trust in the meat industry.

A Real-Time PCR Approach for Rapid Detection of Viable Salmonella Enteritidis in Shell Eggs

Rapid and robust detection assays for Salmonella Enteritidis (SE) in shell eggs are essential to enable a quick testing turnaround time (TAT) at the earliest checkpoint and to ensure effective food safety control. Real-time polymerase chain reaction (qPCR) assays provide a workaround for the protracted lead times associated with conventional Salmonella diagnostic testing. However, DNA-based analysis cannot reliably discriminate between signals from viable and dead bacteria. We developed a strategy based on an SE qPCR assay that can be integrated into system testing to accelerate the detection of viable SE in egg-enriched cultures and verify the yielded SE isolates. The specificity of the assay was evaluated against 89 Salmonella strains, and SE was accurately identified in every instance. To define the indicator for a viable bacteria readout, viable or heat-inactivated SE were spiked into shell egg contents to generate post-enriched, artificially contaminated cultures to establish the quantification cycle (Cq) for viable SE. Our study has demonstrated that this technique could potentially be applied to accurately identify viable SE during the screening stage of naturally contaminated shell eggs following enrichment to provide an early alert, and that it consistently identified the serotypes of SE isolates in a shorter time than conventional testing.

Evaluation of eight commercial Zika virus IgM and IgG serology assays for diagnostics and research

Several commercial Zika virus (ZIKV) serology assays have been developed since the recognition of ZIKV outbreaks as a Public Health Emergency of International Concern in 2016. However, test interpretation for ZIKV serology can be challenging due to antibody cross-reactivity with other flaviviruses like dengue virus (DENV). Therefore, we sought to evaluate the performance of eight commercially available ZIKV IgM and IgG assays across three testing platforms, namely, immunochromatographic tests (ICT), ELISAs and immunofluorescence tests (IIFT). The test panel comprised of 278 samples, including acute and convalescent sera or plasma from ZIKV-confirmed, DENV-confirmed, non-ZIKV and non-DENV patients, and residual sera from healthy blood donors. The ZIKV IgM and IgG serology assays yielded higher test sensitivities of 23.5% - 97.1% among ZIKV convalescent samples as compared to 5.6% - 27.8% among ZIKV acute samples; the test specificities were 63.3% - 100% among acute and convalescent DENV, non-DENV samples. Among the ELISAs and IIFTs, the Diapro ZIKV IgM ELISA demonstrated high test sensitivity (96%) and specificity (80%) when tested on early convalescent samples, while the Euroimmun ZIKV IgG ELISA yielded the highest test specificity of 97% - 100% on samples from non-ZIKV patients and healthy blood donors. For rapid ICTs, the LumiQuick IgM rapid ICT yielded low test sensitivity, suggesting its limited utility. We showed that commercial ZIKV IgM and IgG serology assays have differing test performances, with some having moderate to high test sensitivities and specificities when used in a dengue endemic setting, although there were limitations in IgG serology.

Using cluster analysis to reconstruct dengue exposure patterns from cross-sectional serological studies in Singapore

Background

Dengue is a mosquito-borne viral disease caused by one of four serotypes (DENV1-4). Infection provides long-term homologous immunity against reinfection with the same serotype. Plaque reduction neutralization test (PRNT) is the gold standard to assess serotype-specific antibody levels. We analysed serotype-specific antibody levels obtained by PRNT in two serological surveys conducted in Singapore in 2009 and 2013 using cluster analysis, a machine learning technique that was used to identify the most common histories of DENV exposure.

Methods

We explored the use of five distinct clustering methods (i.e. agglomerative hierarchical, divisive hierarchical, K-means, K-medoids and model-based clustering) with varying number (from 4 to 10) of clusters for each method. Weighted rank aggregation, an evaluating technique for a set of internal validity metrics, was adopted to determine the optimal algorithm, comprising the optimal clustering method and the optimal number of clusters.

Results

The K-means algorithm with six clusters was selected as the algorithm with the highest weighted rank aggregation. The six clusters were characterised by (i) dominant DENV2 PRNT titres; (ii) co-dominant DENV1 and DENV2 titres with average DENV2 titre > average DENV1 titre; (iii) co-dominant DENV1 and DENV2 titres with average DENV1 titre > average DENV2 titre; (iv) low PRNT titres against DENV1-4; (v) intermediate PRNT titres against DENV1-4; and (vi) dominant DENV1-3 titres. Analyses of the relative size and age-stratification of the clusters by year of sample collection and the application of cluster analysis to the 2009 and 2013 datasets considered separately revealed the epidemic circulation of DENV2 and DENV3 between 2009 and 2013.

Conclusion

Cluster analysis is an unsupervised machine learning technique that can be applied to analyse PRNT antibody titres (without pre-established cut-off thresholds to indicate protection) to explore common patterns of DENV infection and infer the likely history of dengue exposure in a population.

P884 Rare case of primary cardiac lymphoma in immunocompetent patient

Primary cardiac lymphoma is a rare tumour especially in immunocompetent person. It is invariably fatal unless diagnosed and treated early. Our patient was a 76 year old Chinese gentlemen, known case diabetes mellitus and hypertension, who presented with 3 months history of failure symptoms. He also had loss of appetite.

His vital signs were stable. There was bibasal crepitation, raised JVP with normal heart sounds and bilateral pedal edema. Chest X-ray showed bilateral pleural effusion.He was admitted for stabilization of heart failure and started on diuretics.

Echocardiography showed the LV ejection fraction was 50% with grade 1 diastolic dysfunction. There was a global pericardial effusion with effusion size 2.52cm maximum at posterior to LV. There was partial RA collapse .Patient was otherwise hemodynamically stable. Patient was observed closely and diuretics continued. Echocardiography on the third day of admission showed a suspicious looking mass in the right atrial (RA) and right ventricular (RV) wall near the AV groove. It become apparent after pericardial effusion became less. Patient was counselled and agreed for pericardial tapping but procedure had to be abandoned as effusion has reduced compared to before (<20mm).

MRI cardiac showed an infiltrating mass around the right atrio-ventricular groove extending to the right ventricular free wall and around the pericardial lining around the ascending aorta and pulmonary trunks. There is inhomogenous signal in STIR with iso-intensity on T1 weighted images. First pass metabolism revealed some vascularity. There was a patchy myocardial enhancement on late gadolinium enhancement. pericardium was thickened with global pericardial effusion- 16mm. Large right pleural effusion seen and minimal left pleural effusion. Mediastinal lymphadenopathy was seen. The finding were suggestive of cardiac lymphoma with differential sarcoma.

Subsequent day, patient develop acute ischemic stroke which was complicated by aspiration pneumonia and septic shock. Fortunately he recovered after 1 week of antibiotics and non-invasive ventilatory support.

FDG PET- CT scan showed FDG-avid primary cardiac lymphoma with pericardial involvement and conglomerate of multiple group of mediastinal and supra clavicular lymph nodes . Bilateral hypermetabolic adrenal nodule were seen but unable to determine its relevance to the primary pathology(lymphoma). No marrow or other organ involvement. Stage is likely IIE.

We were unable to harvest the lymph node because they were too deep. Patient"s family was counselled for cardiac biopsy but family did not want to take the risk as patient was bedridden and fragile. They were also not keen for any chemotherapy or invasive procedure. Once patient was out of infection, they requested to bring back patient to home. He was sent to nursing home for full time care but succumbed to another bout of aspiration pneumonia one week after discharge.

Abstract P884 Figure. Echo, MRI, Pet CT scan

P1342 Secondary cardiac tumour -a metastasis from renal cell carcinoma via transvenous extension

Secondary cardiac tumour is 20-40 times more common than primary cardiac tumour. Most common tumour that metastasize to the heart are lung cancer, breast cancer and hematologic malignancy. Melanoma and pleural mesothelioma has high inclination to metastasize. Other cancer with high rate of cardiac metastasis include gastric, ovarian, renal and pancreatic cancer. The presentation of cardiac metastasis is usually non-specific and sometimes mimic other cardiac condition. We would like to present one such case where we used multimodality approach for proper evaluation.

A 57 year old lady presented with intermittent chest discomfort for one month which worsen on day of admission. Otherwise she had good effort tolerance. Electrocardiogram had no acute ischemic changes and Troponin T was not elevated. Bedside echocardiography revealed a large cardiac mass in right atrium around 66mm x 29mm, protruding to right ventricle. Apart from that noted aneurysm of interatrial septum towards LA.

MRI cardiac showed an inhomogenous mass extending from the right renal vein and inferior vena cava(IVC) into the right atrium(RA). The tumour mass in the right atrium a highly mobile and flops across the tricuspid valve into the right ventricle during ventricular diastole causing right ventricular outflow tract obstruction. The mass was hyperintense on T2- and isointense on T1-weighted images. There was vascularity within the mass with inhomogenous gadolinium enhancement. There was also 2 masses in right kidney , a larger inhomogenous encapsulated mass at the right lower pole and smaller at lower pole. The findings were suggestive of a primary renal cell carcinoma with tumour mass extension into right renal vein, inferior vena cava and into the right atrium.

A staging CT scan thorax , abdomen and pelvis did not show any other possible primary source of cancer and reconfirm the extracardiac finding of the MRI. No evidence of tumour extension into hepatic veins and left renal vein. There was however small nodular opacities in both right and left lung suggesting lung metastasis.

A combined operation was done with our cardiothoracic surgeon and urologist from nearby tertiery hospital. Nephrectomy and removal of tumour thrombus from IVC and RA was done with 18 degree Celcius circulatory arrest with cardiopulmonary bypass.

Section of renal mass showed a poorly circumscribed lobulated tumour with areas of hemorrhage and necrosis. The tumour was close to capsule but has not breached it. The tumour was mainly clear cell carcinoma variant, nuclear grade III. Section from IVC that extend to RA appeared elongated sausage-like measuring 150mm in length and 30mm in diameter had tumour embolus. Pulmonary artery and perirenal blood vessel also had tumour emboli. The hilar nodes however were free from tumour.

Patient recovered well and was discharged home day 9 post operation. Follow-up echocardiogram 3weeks post-op showed no recurrence of the mass and good LV function.

Abstract P1342 Figure. Echo, CTscan, MRI and Pathology images

Force of Infection and True Infection Rate of Dengue in Singapore: Implications for Dengue Control and Management

National data on dengue notifications do not capture all dengue infections and do not reflect the true intensity of disease transmission. To assess the true dengue infection rate and disease control efforts in Singapore, we conducted age-stratified serosurveys among residents after a 2013 outbreak that was the largest dengue outbreak on record. The age-weighted prevalence of dengue immunoglobulin G among residents was 49.8% (95% confidence interval: 48.4, 51.1) in 2013 and 48.6% (95% confidence interval: 47.0, 50.0) in 2017; prevalence increased with age. Combining these data with those from previous serosurveys, the year-on-year estimates of the dengue force of infection from 1930 to 2017 revealed a significant decrease from the late 1960s to the mid-1990s, after which the force of infection remained stable at approximately 10 per 1,000 persons per year. The reproduction number (R₀) had also declined since the 1960s. The reduction in dengue transmission may be attributed to the sustained national vector program and partly to a change in the age structure of the population. The improved estimated ratio of notified cases to true infections, from 1:14 in 2005–2009 to 1:6 in 2014–2017, signifies that the national notification system, which relies on diagnosed cases, has improved over time. The data also suggest that the magnitudes of dengue epidemics cannot be fairly compared across calendar years and that the current disease control program remains applicable.

Echocardiographic and electrocardiographic presentations of patients with endomyocardial biopsy-proven cardiac amyloidosis

OBJECTIVE

Cardiac amyloidosis is under diagnosed and its prevalence is unknown. This is a retrospective, nonrandomised, single centre study of patients with endomyocardial biopsy-proven cardiac amyloidosis focusing on their echocardiographic and electrocardiogram (ECG) presentations. This is the first case series in Malaysia on this subject.

METHODS

We identified all of our endomyocardial biopsyproven cardiac amyloidosis patients from January 2010 to January 2018 and reviewed their medical records. All patients echocardiographic and ECG findings reviewed and analysed comparing to basic mean population value.

RESULTS

In total there are 13 biopsy-proven cardiac amyloidosis patients. All of the biopsies shows light chain (AL) amyloid. Majority of the patients (8, 61.5%) is male, and most of our patients (8, 61.5%) is Chinese. All seven patients on whom we performed deformation imaging have apical sparing pattern on longitudinal strain echocardiogram. Mean ejection fraction is 49.3%, (SD=7.9). All patients have concentric left ventricular hypertrophy and right ventricular hypertrophy. Diastolic dysfunction was present in all of our patients with nine out of 13 patients (69.2%) having restrictive filling patterns (E/A ≥2.0 E/e' ≥15). On electrocardiogram, 12 (92%) patients have prolonged PR interval (median 200ms, IQR 76.50ms) and 9 (69.2%) patients have pseudoinfarct pattern.

CONCLUSION

Echocardiography plays an important role in diagnosing cardiac amyloidosis. The findings of concentric left ventricular hypertrophy with preserved ejection fraction without increased in loading condition should alert the clinician towards its possibility. This is further supported by right ventricular hypertrophy and particularly longitudinal strain imaging showing apical sparing pattern.

A case of successfully managed pregnancy in a patient with complex cyanotic congenital heart disease

Medical advances have increased survival of patients with congenital heart disease. However, cardiac disease in pregnancy carries significant maternal and fetal risks, posing enormous challenges to obstetricians. Cyanotic congenital heart disease is associated with maternal complications such as arrhythmias, thromboembolic events and death. Fetal complications include small for gestational age, miscarriage and prematurity. Cyanotic congenital heart disease patients who continue their pregnancies require holistic multidisciplinary team care with early and coordinated planning for delivery. Management of such patients include early counseling regarding pregnancy-associated risks, close monitoring of their cardiac function and regular scanning for fetal assessment. Choice of anesthesia for these patients requires meticulous planning to achieve a favorable balance between systemic and pulmonary vascular resistance, ensuring minimal change in right-to-left shunting. We report a case of a successfully managed pregnancy in a patient with complex congenital heart disease and a single ventricle of left ventricle morphology.

Repeated failed non-invasive prenatal testing in a woman with immune thrombocytopenia and antiphospholipid syndrome: lessons learnt

We present a case of a 37-year-old Chinese woman (gravida 4 para 0) with a history of immune thrombocytopenia and type IIb antiphospholipid syndrome. She was started on 100 mg of aspirin, 20 mg of prednisolone and 20 mg of subcutaneous low-molecular-weight heparin daily for her fourth pregnancy. She opted for non-invasive prenatal testing for aneuploidy screening but had failed results three times consecutively from insufficient fetal cfDNA initially or high variance in cfDNA counts on redraws. She declined invasive karyotyping. Her pregnancy was complicated by severe pre-eclampsia and fetal growth restriction at 19+6 weeks of gestation and was terminated. Subsequent fetal karyotyping revealed a normal karyotype of 46XY with no apparent abnormalities.

A national common massive transfusion protocol (MTP) is a feasible and advantageous option for centralized blood services and hospitals

BACKGROUND

A common national MTP was jointly implemented in 2011 by the national blood service (Blood Services Group) and seven participating acute hospitals to provide rapid access to transfusion support for massively haemorrhaging patients treated in all acute care hospitals.

METHODS

Through a systematic clinical workflow, blood components are transfused in a ratio of 1:1:1 (pRBC: whole blood-derived platelets: FFP), together with cryoprecipitate for fibrinogen replacement. The composition of components for the MTP is fixed, although operational aspects of the MTP can be adapted by individual hospitals to suit local hospital workflow. The MTP could be activated in support of any patient with critical bleeding and at risk of massive transfusion, including trauma and non-trauma general medical, surgical and obstetric patients.

RESULTS

There were 434 activations of the MTP from October 2011 to October 2013. Thirty-nine per cent were for trauma patients, and 30% were for surgical patients with heavy intra-operative bleeding, with 25% and 6% for patients with gastrointestinal bleeding and peri-partum haemorrhage, respectively. Several hospitals reported reduction in mean time between request and arrival of blood. Mean transfusion ratio achieved was one red cell unit: 0·8 FFP units: 0·8 whole blood-derived platelet units: 0·4 units of cryoprecipitate. Although cryoprecipitate usage more than doubled after introduction of MTP, there was no significant rise in overall red cells, platelet and FFP usage following implementation.

CONCLUSION

This successful collaboration shows that shared transfusion protocols are feasible and potentially advantageous for hospitals sharing a central blood provider.

Glaucoma severity affects diffusion tensor imaging (DTI) parameters of the optic nerve and optic radiation

OBJECTIVES

To evaluate whether MR diffusion tensor imaging (DTI) of the optic nerve and optic radiation in glaucoma patients provides parameters to discriminate between mild and severe glaucoma and to determine whether DTI derived indices correlate with retinal nerve fibre layer (RNFL) thickness.

METHODS

3-Tesla DTI was performed on 90 subjects (30 normal, 30 mild glaucoma and 30 severe glaucoma subjects) and the FA and MD of the optic nerve and optic radiation were measured. The categorisation into mild and severe glaucoma was done using the Hodapp-Parrish-Anderson (HPA) classification. RNFL thickness was also assessed on all subjects using OCT. Receiver operating characteristic (ROC) analysis and Spearman's correlation coefficient was carried out.

RESULTS

FA and MD values in the optic nerve and optic radiation decreased and increased respectively as the disease progressed. FA at the optic nerve had the highest sensitivity (87%) and specificity (80%). FA values displayed the strongest correlation with RNFL thickness in the optic nerve (r=0.684, p ≤ 0.001) while MD at the optic radiation showed the weakest correlation with RNFL thickness (r=-0.360, p ≤ 0.001).

CONCLUSIONS

The high sensitivity and specificity of DTI-derived FA values in the optic nerve and the strong correlation between DTI-FA and RNFL thickness suggest that these parameters could serve as indicators of disease severity.

Abstract P1-02-09: Positive predictive value (PPV) of the diagnosis of atypia in breast core biopsies: An audit of MSKCC breast pathology service

Percutaneous needle core biopsy is the standard of care in the assessment of suspicious breast lesions. The diagnostic term “Atypia” is used in breast biopsy reporting when histologic appearances are suspicious but not diagnostic of malignancy. Multiple histopathological appearances are encompassed by the umbrella term “atypia”, including atypical ductal hyperplasia (ADH), columnar cell change with atypia (CCCWA), which is also known as flat epithelial atypia (FEA), and a miscellaneous group of diagnoses, known as atypia NOS.

A pathologic diagnosis of “atypia” in breast core biopsies usually leads to a recommendation to surgically excise the lesion. Many studies have correlated the diagnosis of “atypia” in core biopsies with the subsequent finding of carcinoma in the surgical excisions, and the percentage of carcinoma found represents the positive predictive value (PPV) of the diagnosis. To date, there is no agreed target PPV for the diagnosis of breast atypia on biopsy, but the most studies have demonstrated a PPV of 20- 40%. Individual “atypia” diagnoses such as CCCWA have an even lower PPV of 10-15%.

One method of performance review is an audit of the average breast-atypia PPV within individual pathology departments, which then can be monitored and studied over time, to detect trends and “diagnostic drift” at an early stage. In addition, assessment of the individual PPV of each breast pathologist allows for analysis of the consistency of the diagnostic practice of each individual with their colleagues. Surprisingly, there have been no major studies assessing the intradepartmental range of PPVs for breast atypia diagnoses to date. In contrast, the American College of Radiology has designed the BIRADS classification system in order to audit and monitor the PPV of breast imaging in diagnosing malignancy.

We undertook to measure the departmental PPV for malignancy following a biopsy diagnosis of breast atypia, and performed an anonymized subanalysis in order to establish the range of PPVs of atypia diagnoses between the sub-specialized breast pathologists within the department.

This study established that the baseline PPV in our department is comparable to previously reported studies at 24%, while the range of PPV for an atypia diagnosis between pathologists is between 22.8 and 25% for 5 of 6 pathologists, with one pathologist demonstrating a higher PPV of 36.8%. ADH was the most common diagnosis of the atypia subtypes, and the PPV for ADH alone was 29.9%. 15% of ADH diagnoses were described as “ADH bordering on low grade DCIS”; within this subgroup the PPV was 48.5%. The PPV for a diagnosis of CCCWA alone was 10%.

This study demonstrates that the PPV for breast atypia in a major tertiary cancer center is approximately 24%. We have demonstrated very reproducible use of this diagnostic term within the department. We plan to use the findings of this study to identify subgroups of patients with a sufficiently low PPV to justify a decision not to proceed to surgical intervention. We aim to develop an algorithm for use in the clinical setting in order to direct further patient management. The ultimate aim of this research is to reduce the number of patients undergoing unnecessary surgical interventions.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P1-02-09.

Quantification of diffusion tensor imaging in normal white matter maturation of early childhood using an automated processing pipeline

OBJECTIVES

The degree and status of white matter myelination can be sensitively monitored using diffusion tensor imaging (DTI). This study looks at the measurement of fractional anistropy (FA) and mean diffusivity (MD) using an automated ROI with an existing DTI atlas.

METHODS

Anatomical MRI and structural DTI were performed cross-sectionally on 26 normal children (newborn to 48 months old), using 1.5-T MRI. The automated processing pipeline was implemented to convert diffusion-weighted images into the NIfTI format. DTI-TK software was used to register the processed images to the ICBM DTI-81 atlas, while AFNI software was used for automated atlas-based volumes of interest (VOIs) and statistical value extraction.

RESULTS

DTI exhibited consistent grey-white matter contrast. Triphasic temporal variation of the FA and MD values was noted, with FA increasing and MD decreasing rapidly early in the first 12 months. The second phase lasted 12-24 months during which the rate of FA and MD changes was reduced. After 24 months, the FA and MD values plateaued.

CONCLUSION

DTI is a superior technique to conventional MR imaging in depicting WM maturation. The use of the automated processing pipeline provides a reliable environment for quantitative analysis of high-throughput DTI data.

KEY POINTS

Diffusion tensor imaging outperforms conventional MRI in depicting white matter maturation. • DTI will become an important clinical tool for diagnosing paediatric neurological diseases. • DTI appears especially helpful for developmental abnormalities, tumours and white matter disease. • An automated processing pipeline assists quantitative analysis of high throughput DTI data.

The early clinical features of dengue in adults: challenges for early clinical diagnosis

BACKGROUND

The emergence of dengue throughout the tropical world is affecting an increasing proportion of adult cases. The clinical features of dengue in different age groups have not been well examined, especially in the context of early clinical diagnosis.

METHODOLOGY/PRINCIPAL FINDINGS

We structured a prospective study of adults (≥ 18 years of age) presenting with acute febrile illness within 72 hours from illness onset upon informed consent. Patients were followed up over a 3-4 week period to determine the clinical outcome. A total of 2,129 adults were enrolled in the study, of which 250 (11.7%) had dengue. Differences in the rates of dengue-associated symptoms resulted in high sensitivities when the WHO 1997 or 2009 classification schemes for probable dengue fever were applied to the cohort. However, when the cases were stratified into age groups, fewer older adults reported symptoms such as myalgia, arthralgia, retro-orbital pain and mucosal bleeding, resulting in reduced sensitivity of the WHO classification schemes. On the other hand, the risks of severe dengue and hospitalization were not diminished in older adults, indicating that this group of patients can benefit from early diagnosis, especially when an antiviral drug becomes available. Our data also suggests that older adults who present with fever and leukopenia should be tested for dengue, even in the absence of other symptoms.

CONCLUSION

Early clinical diagnosis based on previously defined symptoms that are associated with dengue, even when used in the schematics of both the WHO 1997 and 2009 classifications, is difficult in older adults.

Ministry of health clinical practice guidelines: clinical blood transfusion

The Health Sciences Authority (HSA) and the Ministry of Health (MOH) publish clinical practice guidelines on Clinical Blood Transfusion to provide doctors and patients in Singapore with evidence-based guidance for blood transfusion. This article reproduces the introduction and executive summary (with recommendations from the guidelines) from the HSA-MOH clinical practice guidelines on Clinical Blood Transfusion, for the information of readers of the Singapore Medical Journal. Chapters and page numbers mentioned in the reproduced extract refer to the full text of the guidelines, which are available from the Ministry of Health website (http://www.moh.gov.sg/mohcorp/publications.aspx?id=25700). The recommendations should be used with reference to the full text of the guidelines. Following this article are multiple choice questions based on the full text of the guidelines.

Obstetric outcomes in women with end-stage renal disease on chronic dialysis: a review

Pregnancies in women on chronic dialysis for end-stage renal disease are high risk, but outcomes appear to have improved with increasing experience and advances in dialysis care. This paper reviews the existing data on outcomes in such pregnancies to enable evidence-based preconception counselling and anticipation of antenatal complications.

Molar pregnancy with false negative urine hCG: the hook effect

Urine pregnancy tests are widely used in emergency departments as the first screening test for patients of reproductive age presenting with gynaecological problems in order to rule out pregnancy. Conditions such as complete molar pregnancy, which produces large amounts of beta human chorionic gonadotropin (beta-hCG), may cause a false negative result due to an oversaturation of the assay system, known as the "hook effect". We report a case where the exclusion of pregnancy by urine testing led to the initial misdiagnosis of a molar pregnancy as a degenerative fibroid. Physicians need to be reminded of the possibility of false negative results with this commonly used test. Negative or inconclusive results in patients with a high suspicion of pregnancy should be further evaluated by serum quantification of beta-hCG and appropriate sample dilution.

B-Lynch suture for the treatment of uterine atony

INTRODUCTION

Over 125,000 women die of postpartum haemorrhage (PPH) each year, with the commonest cause being uterine atony (75-90 percent). Failing conservative management, hysterectomy is usually the final resort. In 1997, Christopher B-Lynch devised an innovative technique to treat uterine atony, and it has been widely used around the world since its original report. However, there are hardly any reports of this technique being utilised in East Asian countries, including Singapore. Our study reviews the cases in which the B-Lynch suture was used to treat uterine atony, and the clinical outcomes of these cases.

METHODS

A retrospective study of data of all women who delivered between May 2004 and June 2007 was collected from the department's database, to identify patients who had undergone the B-Lynch procedure. Primary PPH is defined as a blood loss of more than 500 ml at or within 24 hours of delivery.

RESULTS

There were a total of 5,470 deliveries during this period, with primary PPH occurring in 100 cases. The B-Lynch procedure was performed in seven women, avoiding the need for a hysterectomy in five cases.

CONCLUSION

Our series of cases treated with the B-Lynch procedure showed that it is an effective method of containing PPH. It has the advantage of being applied easily and rapidly, and should be taught to all trainees and registrars in obstetrics. It should be attempted when conservative management of PPH fails and before any radical surgery is considered.

Foetal peak systolic velocity in the middle cerebral artery: an Asian reference range

INTRODUCTION

The aim of this study was to establish reference values of peak systolic blood flow velocity measurement in the foetal middle cerebral artery (MCA-PSV) in the local Asian obstetric population and to compare our reference ranges with those of previously-published studies.

METHODS

329 normal pregnant women attending the outpatient antenatal clinics of the Department of Obstetrics and Gynaecology in the Singapore General Hospital underwent Doppler ultrasonography at least once between 16 and 40 weeks' gestation. The blood flow velocity recordings from the foetal middle cerebral artery were obtained. New reference ranges were constructed by regressing each parameter on gestational age.

RESULTS

New reference ranges for foetal middle cerebral artery with gestation were constructed for an Asian population. Our reference curves were compared with that of a previously-constructed one.

CONCLUSION

MCA-PSV increases with advancing gestational age. There appear to be differences between Asian and non-Asian reference ranges for MCA-PSV.

The association between maternal depression and frequent non-routine visits to the infant's doctor--a cohort study

BACKGROUND

Perinatal depression is common, but women typically do not seek help for it. We studied its association with frequent non-routine physician visits, which may be a form of help-seeking behaviour.

METHODS

A prospective cohort study of women in their 34th to 38th week of pregnancy at the outpatient obstetrics clinic at a Singapore tertiary hospital was done. Screening was done using the Edinburgh Postnatal Depression Scale and diagnosis of major or minor depressive disorder was made using the SCID-IV. At 6 to 12 months' post-partum, women were screened and interviewed again for depression and asked to report the frequencies with which they had brought their infants to the doctor on non-routine visits in the preceding 6 weeks. Four hundred and seventy-one of the 559 patients recruited before delivery were re-interviewed.

RESULTS

After adjusting for confounders, women who had brought their infants for three or more non-routine visits to the infant's doctor had a significantly higher prevalence of depression (32.6%) than those with fewer visits (13.6%) (OR 2.87, 95% CI 1.41 to 5.85, p=0.004). The relative risk reduction for women who did not bring their infants for frequent non-routine visits was 0.583 (95% CI 0.44 to 0.73, p=0.002). They were also more likely to have poorer perceived emotional support from their families.

LIMITATIONS

These included use of self-reported doctor visits, and relatively high educational levels of the participants.

CONCLUSIONS

Doctors should have a high index of suspicion for enquiring about depression and emotional support in mothers who bring their infants for frequent non-routine visits.

Delayed bleeding after liver biopsy: a dreaded complication

We present an unusual case of percutaneous liver biopsy complicated by delayed haemothorax in a 55-year-old Chinese man with hepatitis C cirrhosis and severe haemophilia A. The patient presented ten days after the initial liver biopsy, and was managed with prompt investigations for confirming the diagnosis, infusion of factor VIII and fresh frozen plasma, and early referral to the surgeon for consideration of surgical repair. The importance of early detection and aggressive therapy is emphasised.

Ultrasonographical features of morbidly-adherent placentas

Morbidly-adherent placentas manifest as placenta accreta, increta or percreta, depending on the depth of placental invasion. These conditions present high risks of severe obstetrical haemorrhage at delivery. The underlying pathology is due to defects in the decidua basalis caused by a variety of insults, such as previous surgery, excessive curettage or infection. The incidence of morbidly-adherent placentas is rising as the frequency of caesarean sections increase. Imaging plays an important role in the antenatal detection of this condition. Based on the case series seen at our local institution, we describe the imaging characteristics of this condition as seen on grayscale ultrasonography, colour/power Doppler ultrasonography, three-dimensional ultrasonography and magnetic resonance imaging.

Intrapartum maternal sinus bradycardia with spontaneous resolution following delivery

Pregnancy is a normal physiological state that is characterised by significant adaptive changes, many of which take place in the cardiovascular system. These adaptations are believed to be the cause for the increased incidence in cardiac arrhythmias in pregnancy and particularly, in labour. We report an unusual case of a healthy 32-year-old primigravida who developed profound intrapartum bradycardia which persisted throughout labour. Spontaneous recovery to pre-labour baseline heart rate occurred following spontaneous vaginal delivery. Maternal and foetal statuses remained satisfactory during labour. This case report underscores the importance of recognising that arrhythmias in various forms are common in labour. In the absence of detectable underlying cardiac disease or maternal and foetal compromise, continuation of the labour with a view to vaginal delivery should be the goal.

Intramuscular immunization with DNA construct containing Der p 2 and signal peptide sequences primed strong IgE production

BACKGROUND

Previous studies demonstrated that allergen gene vaccination induced TH1-skewed responses and inhibited IgE production. This study evaluated and characterized the immune responses induced by three DNA constructs encoding different forms of Der p 2 for safe and efficacious vaccination against mite allergy.

METHODS

Mice were immunized intramuscularly with DNA constructs encoding a major mite allergen, Der p 2, without a signal peptide (p2), with a signal peptide (p52), and with a signal peptide plus lysosomal-targeting sequence (p52-LA), respectively, followed by TH2-skewed protein challenge. Antibody and T-cell cytokine responses were assessed by ELISA. Primed dendritic cells (DCs) were adoptively transferred to naïve mice and humoral responses were examined after protein challenge. The circulating Der p 2 protein was detected by sandwich ELISA.

RESULTS

Mice immunized with p52-LA showed strong and clear-cut TH1-type response, as evident by high IFN-gamma production and elevated levels of Der p 2-specific IgG2a production whereas construct p2 induced only moderate levels of TH1 response. In contrast, mice immunized with construct p52 showed a mixed TH1/TH2 phenotype and produced substantial circulating Der p 2 protein. Mice adoptively transferred with DCs primed by p52 construct, but not by the p2 or p52-LA constructs, were sensitized to produce high levels of Der p 2-specific IgE.

CONCLUSIONS

Immunization with DNA construct encoding a signal peptide could potentially prime TH2-skewed responses and IgE production. The additional inclusion of lysosomal-targeting sequences to such construct could improve the safety and efficacy of DNA vaccination against allergy.

Tocolytic treatment for the management of preterm labour: a systematic review

Spontaneous preterm labour and delivery accounts for approximately one-third of preterm births, which is the predominant cause of perinatal mortality and morbidity. This review aims to evaluate the evidence on the benefits and harms of five classes of tocolytic therapy, namely: betamimetics, calcium channel blockers, magnesium, non-steroidal anti-inflammatory agents, and atosiban. We performed a systematic review of the effectiveness of tocolytics to stop uterine contractions (first-line therapy). Reports of randomised controlled trials from searches of MEDLINE, bibliographies of review articles, Cochrane Collaboration and its Pregnancy and Childbirth Review Group between 1966 and 2003 were identified, using the search terms "randomised controlled trial" (RCT), "preterm labor", "tocolysis", "betamimetics", "ritodrine", "prostaglandin synthetase inhibitors", "indomethacin", "calcium channel blockers", "nifedipine", "oxytocin receptor blockers", "atosiban", and "magnesium sulphate". Studies on women with preterm labour comparing the effects of a tocolytic with a placebo or no treatment that met our inclusion criteria, were included. To our knowledge, the trials were conducted mainly before 1999 and there were no placebo-controlled trials after that. Of the 86 articles identified and evaluated, 14 first-line studies met more stringent requirements for meta-analyses. Tocolytics were associated with significant decreases in the odds of delivery within 24 hours (odds-ratio [OR] 0.54, 95 percent confidence interval [CI] 0.32-0.91) and 48 hours (OR 0.47, 95 percent CI 0.30-0.75). These effects were significant for beta-agonists, atosiban and indomethacin, but not magnesium sulphate. Maternal side-effects significantly associated with betamimetics were pulmonary oedema, cardiac arrhthymias and hypokalaemia. Although calcium antagonists have not been evaluated against placebo, comparative trials with beta-agonists have shown more favourable neonatal outcomes and better prolongation of gestation. In conclusion, the management of threatened preterm labour with first-line tocolytic therapy can prolong gestation. However, the time gained in-utero need to be optimised. There is no clear first-line tocolytic agent. The use of tocolytic agents should be individualised and based on maternal condition, potential side-effects and gestational age.

Confinement and other psychosocial factors in perinatal depression: a transcultural study in Singapore

BACKGROUND

To investigate the prevalence, socio-cultural and psychosocial risk factors for perinatal depression in Singaporean women.

METHOD

A prospective cohort of 559 women was interviewed antenatally and at six weeks' postpartum at a tertiary hospital. Women were interviewed for diagnosis of depression using a two-stage design, with a screening questionnaire and diagnostic interview.

RESULTS

Postnatally, a negative confinement experience was associated with depression. Other independent factors included poor emotional support, a past history of depression, unplanned pregnancy and perceived potential conflicts with relatives over childcare antenatally and dissatisfaction, poor instrumental support postnatally. The prevalence of depression antenatally and postnatally was 12.2% and 6.8%, respectively.

LIMITATIONS

Measures of satisfaction with social support were based on self-report; there were high dropout rates at six weeks' postpartum; and other modulating social factors such as pre-existing interpersonal conflicts were not studied.

CONCLUSIONS

Perinatal depression in Singaporean women is common. Contrary to expectations, a negative 'confinement' experience is a significant risk factor for postnatal depression, and is not universally welcomed by women. Depression is modulated by dissimilar sets of psychosocial factors antenatally and postnatally.

Clinico-pathological analysis of myelodysplastic syndromes according to French-American-British classification and international prognostic scoring system

INTRODUCTION

The aim of this study was to analyse the clinico-pathological features of a cohort of patients with myelodysplastic syndromes (MDS).

MATERIALS AND METHODS

The clinical and pathological data of 43 MDS patients over a 3-year period were reviewed. Survival analysis was performed according to the French-American-British (FAB) classification and International Prognostic Scoring System (IPSS) using the Kaplan-Meier method. Selected published studies for comparison were identified from MEDLINE search.

RESULTS

The patients were followed up for a median duration of 175 days (range, 2 to 1044 days). The median survival for refractory anaemia (RA) and refractory anaemia with ringed sideroblasts (RARS) has not been reached, but that for refractory anaemia with excess blasts (RAEB), refractory anaemia with excess blasts in transformation (RAEB-T) and chronic myelomonocytic leukaemia (CMML) was 250 days, 49 days and 44 days, respectively. The median survival for the low-risk and intermediate-1 IPSS categories has not been reached, while that for the intermediate-2 and high-risk categories was 58 days and 49 days, respectively. The survival analyses, according to the FAB classification and IPSS system, were statistically significant (P <0.05). Comparison of our data with those from neighbouring and Western countries revealed both similarity and disparity. We also noted different cytogenetic information in our cohort of patients.

CONCLUSIONS

We found distinctly unique cytogenetic and clinico-pathological characteristics in our MDS patients. However, whether true biological differences exist among MDS patients in different geographies and populations with different genetic and environmental backgrounds require further large multinational study.

Stability of extemporaneously prepared saquinavir formulations

AIMS

The effects of pH and excipients on the stability of saquinavir in extemporaneously prepared suspensions were assessed. The stability of a developed extemporaneously prepared saquinavir suspension was then determined at 5 and 25 degrees C over 30 days.

METHOD

Extemporaneous saquinavir 2 mg/mL formulations were prepared from soft gelatin capsule (Fortovase). Four batches of the formulations were buffered at pHs 2, 4, 5 and 7, whereas the other five batches were prepared in Milli-Q water, 0.5% (w/v) citric acid, 0.1% (w/v) sodium ascorbate, 10% (v/v) syrup and in vehicle containing both 0.5% (w/v) citric acid and 0.1% (w/v) sodium ascorbate. The stability of these formulations was tested at 25 degrees C. A final formulation of saquinavir suspension (60 mg/mL) containing both 10% (v/v) syrup and 0.5% (w/v) citric acid was developed and tested for stability at 5 and 25 degrees C for up to 30 days using a stability-indicating high-performance liquid chromatographic method.

RESULTS

Saquinavir was most stable at pH 2-4. Formulations containing sodium ascorbate, citric acid and syrup or both citric acid and sodium ascorbate were significantly more stable than the control formulation (saquinavir 2 mg/mL in Milli-Q water).

CONCLUSION

The pH for optimal stability of saquinavir was around 2-4. Besides pH adjustment, saquinavir could also be stabilized by adding anti-oxidants. The saquinavir 60 mg/mL formulation prepared with about a pH of about 4 was stable at both 5 and 25 degrees C for at least 30 days.

Audit of 'crash' emergency caesarean sections due to cord prolapse in terms of response time and perinatal outcome

OBJECTIVE

The objective was to audit 'crash' emergency caesarean sections (CS) with respect to response time (the diagnosis to delivery interval [DDI]) and perinatal outcome.

MATERIALS AND METHODS

The computerised database at the Singapore General Hospital (SGH) delivery suite was used to identify all cases of 'crash' emergency CS activated for the diagnosis of cord prolapse from 1992 to 2002. Patients' case notes and neonatal charts were reviewed and the following variables were evaluated: parity, gestational age at the time of delivery and the DDI. Neonatal outcome was measured by Apgar scores at 1 and 5 minutes, cord pH and admission to the neonatal intensive care unit (NICU).

RESULTS

A total of 34 cases of umbilical cord prolapse were identified from 29,867 deliveries, giving an incidence of 0.11% (1 in 900). The median gestational age was 38.5 weeks (range, 25 to 41 weeks). The median time from diagnosis to delivery was 20 minutes (range, 10 to 40 minutes). Seventy-six percent (19/30) were delivered within 30 minutes. The time of diagnosis was not recorded for 5 cases. Sixty-three percent of neonates had an Apgar score < or = 7 at 1 minute of life, increasing to 97% at 5 minutes. There were 3 NICU admissions for reasons of prematurity. There was no perinatal mortality. Cord pH was not performed for 47% of (14/30) neonates. Among the remaining 16 neonates, an umbilical cord pH of < or = 7.20 was found in 62% (10/16). There was poor correlation between the DDI and umbilical cord pH.

CONCLUSION

Three-quarters of our 'crash' emergency CS for cord prolapse were performed within 30 minutes with a good perinatal outcome. However, we have identified areas for improvement to optimise further the operational efficiency of 'crash' emergency CS.

Obstetric cholestasis: current opinions and management

Obstetric cholestasis (OC) is a pregnancy-specific liver condition that typically presents with generalised pruritus in the absence of a rash in the late second trimester or third trimester. It is more common in certain ethnic groups, particularly those from South Asian, South American, Nordic and Scandinavian regions, and has a familial and genetic basis. Recent research suggests that the pathophysiology may reside in mutations in genes that code for bile acid transporter proteins. Mutations involving the bile acid transporters may impair maternal excretion and influence transplacental passage of bile acids. It is hypothesised that the surge in pregnancy steroid hormones may result in genetically predisposed women developing cholestasis. The condition is also associated with increased perinatal morbidity and mortality, particularly from preterm labour, fetal distress and intrauterine deaths. Animal studies have shown that bile acids are cardiotoxic, which may help explain the condition's association with fetal distress and stillbirths. Accurate diagnosis relies on a high index of suspicion, and the findings of abnormal liver function tests and raised serum bile acid levels after the exclusion of other organic causes of liver disease. Ursodeoxycholic acid helps relieve symptoms, improve serum bile acid levels and possibly has a cardioprotective effect. Active management, in the form of close antepartum fetal monitoring and delivery before 37 weeks, helps to decrease the risk of intrauterine deaths, though possibly at the expense of increased obstetric intervention. Following delivery, there is usually a dramatic improvement of symptoms and resolution of the condition. Women should be counselled about the high recurrence risk of OC in subsequent pregnancies.

A prospective validated model for predicting axillary node metastases based on 2,000 sentinel node procedures: the role of tumour location [corrected]

AIMS

The purpose was to identify the independent predictive factors of axillary lymph-node metastases (ALNM) in infiltrating ductal carcinoma (IFDC) and to create a prospective, validated statistical model to predict the likelihood of ALNM in patients in the present era of sentinel lymph-node (SLN) biopsy and enhanced histopathology.

METHODS

Univariate and multivariate analyses of 13 clinicopathological variables (including tumour location) were performed to determine predictors of ALNM in 1659 eligible SLN biopsy procedures. A logistic regression model was developed and then prospectively validated on a second population of 187 subsequent consecutive procedures.

RESULTS

Age, pathological tumour size, palpability, lymphovascular invasion (LVI), histological grade, nuclear grade, ductal histological subtype, tumour location (quadrant) and multifocality were associated with ALNM in univariate analyses (P < 0.001). Of these, only palpability and histological grade were not statistically associated with ALNM in the multivariate analysis (P> 0.05). The frequency of ALNM in upper-inner-quadrant (UIQ) tumours was 20.6%, compared with 33.2% for all other quadrants (P<0.0005). There was no statistical difference between UIQ and other-quadrant tumours in any clinicopathological variables analysed. The logistic regression model, developed based on the population of 1659, had the same accuracy, sensitivity, specificity, positive predictive value and negative predictive value when applied prospectively to the second population.

CONCLUSION

Tumour size, LVI, age, nuclear grade, histological subtype, multifocality and location in the breast were independent predictive factors for ALNM in IFDC. ALNM is less frequent in UIQ tumours than in other-quadrant tumours. Our prospectively validated predictive model could be valuable in pre-operative patient discussions, although staging of the axilla in the individual patient remains necessary.

Management of thromboembolic disease in pregnancy

Venous thromboembolism (VTE) is the leading cause of maternal mortality and morbidity in developed countries including Singapore. The physiological changes of pregnancy and other factors, such as maternal age, parity, obesity, operative delivery, general anaesthesia and congenital and acquired thrombophilia, further increase the risk of VTE throughout all three trimesters of pregnancy, including the puerperium. VTE has a wide spectrum of clinical presentations and a high index of clinical suspicion is vital. Clinicians should not withhold the use of chest X-rays and ventilation-perfusion (V/Q) lung scans in pregnancy as the radiation emitted is well within the safety limits to the fetus. Most treatment guidelines are based on studies in non-pregnant populations. Heparin is the preferred anticoagulant as it does not cross the placenta and therefore carries no teratogenic risk to the fetus. There is increasing experience and confidence in the use of fixed dose subcutaneous low molecular weight heparin (LMWH) which removes the need for cumbersome monitoring, thereby allowing outpatient treatment. LMWH may also have a lower risk of osteopaenic complications compared to unfractionated heparin. With the exception of acute phase treatment of pulmonary embolism, LMWH is used in all other aspects of the treatment of VTE in pregnancy, including thromboprophylaxis. Risk stratification of women into high and low risk allows judicious use of anticoagulants for thromboprophylaxis. Antenatal thromboprophylaxis with LMWH is reserved for high-risk women, while low-risk women will only require such cover in the postpartum period.

The course of pregnancy in a patient with nail-patella syndrome

INTRODUCTION

The nail-patella syndrome is a rare autosomal dominant condition with high penetrance. Pregnancy in such a patient is rare and we believe this to be the first report of a live birth occurring in a patient with nail-patella syndrome.

CLINICAL PICTURE

A 25-year-old patient presented in her first pregnancy with nephrotic syndrome associated with characteristic bone abnormalities and nail dysplasia and was later diagnosed to have nail-patella syndrome. In her second pregnancy, the course of her pregnancy was complicated by further deterioration of renal function with superimposed pre-eclampsia resulting in early delivery at 28 weeks.

CONCLUSION

Such pregnancies should be regarded as high risk and managed jointly with the renal physician in a tertiary care centre to ensure an optimal outcome to the mother and baby.

Outcome of pregnancy in Asian women with systemic lupus erythematosus: experience of a single perinatal centre in Singapore

OBJECTIVE

To study maternal and fetal outcomes in women with systemic lupus erythematosus (SLE).

MATERIALS AND METHODS

Retrospective study of 27 pregnancies in 18 women with SLE in a single centre.

RESULTS

The mean age was 30 years and most patients were nulliparous. Twenty-six of 27 pregnancies were in disease remission at the time of booking. Renal impairment was present in 7 pregnancies (6 women), of whom 2 were in end-stage renal disease on dialysis. Gestational diabetes developed in 4 pregnancies. There were 6 cases of pre-existing hypertension and 5 with superimposed pre-eclampsia. One woman developed intrapartum eclampsia. Two women had secondary antiphospholipid syndrome (APS) and suffered late fetal losses; in addition, they also developed SLE flares in the form of autoimmune haemolytic anaemia in the postpartum period. There was no maternal mortality. There was one termination of pregnancy for severe renal disease. The median gestational age at delivery was 38 weeks (range, 24 to 40 weeks) and the mean birth weight was 3047 g; the median Apgar scores were 8 and 9 at 1 and 5 minutes of life, respectively. There were 5 cases of intrauterine growth restriction (IUGR), 4 of which occurred in women with renal impairment. There were no cases of congenital heart block or neonatal lupus. There was a late fetal loss at 24 weeks in a woman with secondary APS. There were 2 preterm deliveries (7.4%) due to intervention for IUGR.

CONCLUSION

Good pregnancy outcomes can be expected in women with SLE in remission. Pre-pregnancy counselling is crucial to achieve this. All pregnancies should still be considered high risk and be managed jointly between the obstetricians, the perinatologists and the physicians. In particular, those with renal impairment are at increased risk of IUGR, superimposed pre-eclampsia and preterm births. Co-existing APS augurs a poorer prognosis for pregnancy outcome, and may present atypically as autoimmune haemolytic anaemia in the postpartum period.

Complete branchial fistula. Case report and review of the literature

Branchial anomalies, a result of aberrant embryonic development, are rarely seen in clinical practice. Lesions of the second branchial pouch commonly present as a neck lump or discharging sinus that may be complicated by infection. Clinical examination often reveals the lesion to be related to the junction of the upper two thirds and the lower one third of the sternocleidomastoid muscle. Branchial fistulas often present as a discharging sinus in the neck with the fistula tract extending upward within the deep neck tissue for a variable distance. A complete branchial fistula is one that has a defined internal opening in the tonsillar area and an external opening at the skin overlying the sternocleidomastoid muscle at the junction of the upper two thirds and the lower one third of the muscle. The incidence of such lesions is extremely rare. Surgical excision is the treatment of choice for branchial anomalies. We present the case of a patient who presented with a complete branchial fistula and discuss the clinical presentation and surgical management of such lesions, with a review of the relevant literature.

Her-2/neu and breast cancer

Breast cancer is the most common malignancy in women in the United States in the year 2000. The proto-oncogene Her-2/neu (c-erb-B2) has become an increasingly important prognostic and predictive factor in breast cancer. Overexpression/amplification of the Her-2/neu has been associated with a worse outcome in patients with breast cancer. Herceptin, a "humanized" murine monoclonal antibody directed against the extracellular domain of the Her-2/neu protein, is being used to treat breast cancer that overexpresses Her-2/neu. The status of Her-2/neu in the tumor has become a critical factor in the management strategy of a breast cancer patient. The objective of this article is to provide a comprehensive review of all aspects of Her-2/neu in breast cancer, including biology, prognostic and predictive value, targeted Herceptin therapy, and the laboratory testing of Her-2/neu.

An integrated approach in the discovery and characterization of a novel nuclear protein over-expressed in liver and pancreatic tumors

An integrated approach in protein discovery through the use of multidisciplinary tools was reported. A novel protein, Hcc-1, was identified by analysis of the hepatocellular carcinoma (HCC)-M cell proteome. The assembled EST sequence of the 210 amino acid novel protein was subsequently confirmed by rapid amplification of cDNA ends (RACE). A total of 687 bp at the 5' untranslated region of Hcc-1 was identified. Promoter activity and several upstream open reading frames (uORFs) were demonstrated at this region. Bioinformatics prediction showed that the first 42 amino acids of the protein is a SAP domain with sequence matches to hnRNP from various vertebrate species. The Hcc-1 protein was localized to the cell nucleus while the gene was localized to chromosome 7q22.1. Hcc-1 cDNA level was increased in pancreatic adenocarcinoma. The level was also increased in well-differentiated hepatocellular carcinoma but decreases as the carcinoma progressed to a poorly differentiated stage.

Lymphovascular invasion enhances the prediction of non-sentinel node metastases in breast cancer patients with positive sentinel nodes

BACKGROUND

Fifty percent of patients with sentinel lymph node (SLN) metastases have no metastatic disease in non-SLNs on axillary lymph node dissection (ALND). The goal of this study is to determine which patients have metastatic disease limited to the SLN, and, therefore, may not require completion ALND.

METHODS

Of the first 1000 patients undergoing SLN biopsy at Memorial Sloan-Kettering Cancer Center, using a combined blue dye and isotope technique, 231 (26%) had positive SLN. Of these, 206 underwent completion ALND. They are the study group for this report.

RESULTS

The likelihood of non-SLN metastasis was inversely related to three clinicopathologic variables: tumor size < or = 1.0 cm; absence of lymphovascular invasion (LVI); and SLN micrometastases (< or = 2 mm). None of 24 patients with all three predictive factors had non-SLN metastases, whereas 58% of patients with none of the factors had disease in the non-SLN.

CONCLUSION

Patients with small breast cancers, no LVI, and SLN micrometastases have a low risk of non-SLN metastases, and may not require completion ALND.

A distinct expression of CC chemokines by macrophages in nasopharyngeal carcinoma: implication for the intense tumor infiltration by T lymphocytes and macrophages

Nasopharyngeal carcinoma (NPC) is characterized by harboring Epstein-Barr virus genes in the tumor cells and an intense infiltration of leukocytes in the tumor tissue. These infiltrating cells are mainly composed of T lymphocytes and macrophages. The mechanism of this intense infiltration has long been a puzzle. We attempted to address this issue by studying the expression of CC chemokines, which are responsible for recruiting both T cells and macrophages, by an immunohistochemical approach. In biopsies obtained from nasopharynx of 17 NPC patients that contained tumor cells, expression of macrophage inflammatory protein 1alpha (MIP-1alpha), MIP-1beta, macrophage chemoattractant protein-1 (MCP-1), MCP-2, MCP-3, and RANTES was detected in the tumor-infiltrating cells, with MIP-1alpha and MCP-1 found in nearly all biopsies and the others relatively less frequently. Furthermore, expression of interferon-gamma (IFN-gamma) was also observed in tumor-infiltrating cells. In contrast, CC chemokines and IFN-gamma were rarely expressed in the 13 control biopsies that were either normal or with nonspecific inflammation, and in 4 biopsies from untreated NPC patients that contained no tumor cells. Using an immunofluorescent double-staining method, MIP-1alpha and MCP-1 were identified to be associated with macrophages, and IFN-gamma with T cells. Moreover, expression of CCR2 and CCR5, the receptors for these chemokines, was also detected in the tumor-infiltrating cells. These data indicate that the intense tumor infiltration by T cells and macrophages is a result of active recruitment. It seems possible that the intense infiltration of leukocytes in NPC tumor tissue is initiated by the activated tumor-reactive T cells. T cells migrate into the tumor tissue in an antigen-specific mode, and IFN-gamma secreted from these pioneer T cells activates tissue macrophages to express CC chemokines, especially MIP-1alpha and MCP-1, which consequently recruit more T cells and macrophages into the tumor tissue.

In microdissected ductal carcinoma in situ, HER-2/neu amplification, but not p53 mutation, is associated with high nuclear grade and comedo histology

BACKGROUND

HER-2/neu and p53 are two molecular markers that have been the focus of investigation in patients with invasive breast carcinoma. However, most of the published data have relied on immunohistochemical detection of the proteins as a surrogate marker of the underlying genetic alterations, a detection method that often gives variable results due to technical factors. In addition, there are limited data documenting HER-2/neu amplification and p53 mutations in the various histologic subtypes of ductal carcinoma in situ (DCIS). The authors evaluated a series of microdissected, pure DCIS lesions comprising a spectrum of morphologic subtypes (comedo, micropapillary, papillary, cribriform, and solid) and their corresponding normal breast tissue for genetic aberrations in HER-2/neu and p53.

METHODS

HER-2/neu amplification was determined by differential polymerase chain reaction, and p53 mutations were identified by single-strand conformation polymorphism analysis.

RESULTS

HER-2/neu amplification was identified in 12 of 30 DCIS samples (40%), and p53 mutations were identified in 6 of 30 DCIS samples (20%). The genetic alterations were not present in any of the normal breast tissue samples. HER-2/neu amplification occurred predominantly in the comedo subtype (69% vs. 18% of the noncomedo subtype; P = 0.008) and in lesions of high nuclear grade (63% vs. 14% of low grade; P = 0.01). There was no difference in the frequency of p53 mutations among the subtypes or between low grade and high grade lesions. No correlation between the presence of the two genetic alterations was observed.

CONCLUSIONS

The presence of HER-2/neu amplification, but not p53 mutations, correlates with histologic subtype and nuclear grade. The relatively frequent occurrence of HER-2/neu amplification and p53 mutations in DCIS tissue and their absence in normal breast tissue suggest that these genetic aberrations are important early in breast duct carcinogenesis.

Complications of foreign bodies in the esophagus

Major complications of foreign bodies in the esophagus carry significant morbidity and mortality risks. A retrospective case control study was performed to assess the factors associated with major complications. In total, 273 patients seen within a 7-year period were divided into 2 groups; 253 had no or minor complications, and 20 had major complications. Age, sex, duration of the foreign body, total white cell count (TWC), and nature and site of the foreign body were analyzed in the 2 groups. The major complication rate was 7.3%. Duration of the foreign body and TWC were the only statistically significant factors associated with major complications. Six patients required open neck exploration, 1 had an open thoracotomy, and 13 were treated by endoscopic removal. There were 2 deaths. Given the significant morbidity and mortality risks, we conclude that patients with a prolonged history of a foreign body in the esophagus and a raised TWC should be treated urgently.