Stella Sin Yee Ho

Renal screening in children after exposure to low dose melamine in Hong Kong: cross sectional study

Objective To investigate the renal outcomes of children after exposure to low dose melamine in Hong Kong. Design Cross sectional study. Setting Special assessment centres, Hong Kong. Participants 3170 children (1422 girls and 1748 boys) aged 12 years or less referred from territory-wide primary care clinics after daily consumption for one month or more of milk products tainted with melamine. Main outcome measures Presence of renal stones and haematuria. Results One child had a confirmed renal stone, seven were suspected of having melamine related renal deposits, and 208 (6.6%) were positive for blood in urine by reagent strip. A proportion of these children were followed up at the special assessment centre, but only 7.4% of those positive for blood on reagent strip were confirmed by microscopy, suggesting an overall estimated prevalence of less than 1% for microscopic haematuria. Conclusions No severe adverse renal outcomes, such as acute renal failure or urinary tract obstruction, were detected in children after exposure to low dose melamine. Our results were similar to territory-wide findings in Hong Kong. Even including the seven children with suspected renal deposits, the prevalence of suspected melamine related abnormalities on ultrasonography was only 0.2%. None of these children required specific treatment. The prevalence of microscopic haematuria was probably overestimated by the reagent strip. These data suggest that large scale and urgent screening programmes may not be informative or cost effective for populations who have been exposed to low dose melamine.

Disappearing suprarenal masses in fetuses and infants

Abstract This paper presents 12 infants (9 boys, 3 girls) in whom the diagnosis of a suprarenal mass (10 left, 2 bilateral) was made on antenatal sonography. All were otherwise healthy neonates who were born at term after a normal pregnancy, labor and delivery. The masses ranged from 1 to 3.5 cm in diameter on initial scans at gestational ages of 19–35 weeks. Eleven masses were hyperechoic and 4 of these contained small, well-defined cysts. The 12th was hypoechoic. Follow-up sonography showed complete disappearance of the mass antenatally in 1 case and postnatally by 4–6 months in 5 cases; there was marked diminution in the size of the mass by 2 months of age in 4 infants, by 4 months in 1 case and by 15 months in 1 case. Eleven were managed nonoperatively. Laparotomy (after disappearance of the mass) in the 12th case revealed only some fibrous tissue. The 11 echogenic masses resemble previously reported imaging findings in infants with histologically proven intra-abdominal sequestrated lung. Conservative management with careful sonographic follow-up should, therefore, be considered in otherwise healthy fetuses or neonates with these imaging findings. We are less certain what the hypoechoic mass represented.

Association of general and abdominal obesities and metabolic syndrome with subclinical atherosclerosis in asymptomatic Chinese postmenopausal women

Objective: This study aimed to investigate the relationships between obesity, especially abdominal obesity, andmetabolic syndrome (MS) with carotid intima-media thickness (IMT) and plaque, markers of subclinical atherosclerosis, in asymptomatic Chinese postmenopausal women in Hong Kong. Design: A total of 518 postmenopausal women aged 50 to 64 years were recruited through random telephone dialing. Body mass index (BMI), waist circumference, waist-to-hip ratio, sociodemographic characteristics, blood pressures, medical, biochemical and lifestyle factors were obtained. MS was defined on the basis of the National Cholesterol and Education Program, Adult Treatment Panel III criteria. Subclinical atherosclerosis was determined by measuring IMT and plaque using high-resolution B-mode ultrasonography. Results: Women with a BMI of 25 kg/m2or greater, a waist circumference of 80 cm or greater, a waist-to-hip ratio of 0.85 or greater, or MS were observed to have higher IMT values and prevalence of plaque. Multivariate analyses revealed that waist circumference was significantly associated with IMT independent of age, hormone therapy, lifestyle and sociodemographic factors, and BMI (P < 0.05), whereas a waist-to-hip ratio of 0.85 or greater was significantly associated with plaque (odds ratio = 1.7; 95% CI: 1.0-2.8) after controlling for age, hormone therapy, lifestyle and sociodemographic factors, BMI, and the traditional cardiovascular risk factors. MS was also associated with IMT after adjustment for age, hormone therapy, lifestyle and sociodemographic factors, and BMI (P < 0.05), whereas its association with plaque was also significant (odds ratio = 1.7; 95% CI: 1.0-2.6) after controlling for age. Conclusions: Abdominal obesity and MS are independent of general obesity markers of subclinical atherosclerosis in Chinese postmenopausal women.

Differential Associations of Traditional and Non-Traditional Risk Factors with Carotid Intima-Media Thickening and Plaque in Peritoneal Dialysis Patients

Background: This study sought to examine the associations of traditional and non-traditional cardiovascular risk factors with carotid intima-media thickening and plaque in peritoneal dialysis (PD) patients. Methods: A cross-sectional study was performed in 147 PD patients with carotid intima-media thickness (IMT) and plaque assessed by B-mode ultrasonography and fasting blood collected for biochemical measurements. Results: On univariate analysis, age, smoking history, fibrinogen, C-reactive protein (CRP), adiponectin, fetuin-A, lipoprotein(a) and diastolic blood pressure were associated with carotid IMT while age, smoking history, diabetes, CRP and diastolic blood pressure were associated with carotid plaque. Using multivariate analysis, elevated CRP (p = 0.015) and serum calcium (p = 0.022) were associated with carotid plaque but not with IMT. CRP and serum calcium were synergistically associated with carotid plaque in that those with CRP > median and serum calcium > median showed the highest prevalence of carotid plaque than either factor alone (p = 0.003). Conclusions: An elevated CRP appeared to be a better biomarker of presence of carotid plaque than intima-media thickening. Furthermore, CRP and serum calcium showed synergistic association with presence of carotid plaque. However, our study was limited by the cross-sectional design and baseline laboratory abnormalities were inevitably confounded by the treatment already given, resulting in difficulty to distinguish cause and effect relationship. Nevertheless, these observations warrant further investigation as it may potentially have important implications on differentiating therapeutic strategies for reducing carotid IMT and plaque progression in PD patients.

Comparison of clinical outcomes of tris-acryl microspheres versus polyvinyl alcohol microspheres for uterine artery embolization for leiomyomas: results of a randomized trial.

PURPOSE To compare tris-acryl microspheres and polyvinyl alcohol (PVA) microspheres as embolic agents in uterine artery embolization (UAE) for uterine leiomyomas in terms of clinical outcome, inflammatory response, and adverse reactions. MATERIALS AND METHODS A double-blinded randomized controlled trial was performed, with 27 patients in the tris-acryl microsphere group and 29 in the PVA microsphere group. The primary endpoint was clinical success, defined as a 2-year freedom from subsequent surgery as a result of persistent or deteriorated symptoms. Secondary endpoints included (i) posttreatment leiomyoma enlargement, (ii) leiomyoma volume reduction at 3 and 9 months, (iii) significant residual intratumoral perfusion, (iv) increase in inflammatory and stress markers, (v) incidence of complications, and (vi) duration of hospital stay. RESULTS There was no statistically significant difference between the two groups in patient demographics, clinical presentation, initial tumor findings, change in inflammatory and stress markers after treatment, incidence of complications, and duration of hospital stay. Tris-acryl microspheres were associated with a higher rate of clinical success than PVA microspheres (96.3% [26 of 27] vs 69% [20 of 29]; P = .012), a lower incidence of posttreatment leiomyoma enlargement (P = .030), and a lower incidence of significant residual intratumoral perfusion (P = .030). CONCLUSIONS In the treatment of uterine leiomyomas, UAE with tris-acryl microspheres was associated with a higher clinical success rate, a lower incidence of tumor enlargement, and no significant differences in adverse reactions and inflammatory response compared with the use of PVA microspheres. Tris-acryl microspheres therefore represent the preferred agent for UAE of uterine leiomyomas.

Intraoperative laparoscopic sonography for improved preoperative sonographic pathologic characterization of adnexal masses.

This study compares the diagnostic accuracy of laparoscopic sonography and transvaginal sonography in the evaluation of adnexal masses. Fifty‐eight women underwent transvaginal sonography, which showed 69 adnexal masses, and laparoscopic ultrasonography, which showed 68 adnexal lesions. Conventional gray‐scale ultrasonography (using transvaginal sonography and laparoscopic ultrasonography) was performed with morphologic characterization of internal architecture, followed by color Doppler imaging with spectral Doppler analysis where possible. A specific diagnosis was obtained with transvaginal sonography and laparoscopic ultrasonography based on a combination of imaging features. The specific diagnosis obtained with each imaging modality was compared with the final histologic diagnosis as the gold standard in 57 patients with 68 adnexal masses who underwent cystectomy or oophorectomy. The ability of laparoscopic sonography to detect the contralateral ovary and any residual ovarian tissue in the presence of a mass was also compared with transvaginal sonography. The accuracy of laparoscopic ultrasonography in the characterization of adnexal masses was 83.8% and that of transvaginal sonography was 73.5% (P < 0.05). Laparoscopic sonography showed greater morphologic detail than that obtained with transvaginal sonography, allowed more precise and specific characterization of adnexal masses, and detected additional adnexal lesions not evident on preoperative transvaginal sonography. Laparoscopic ultrasonography showed the contralateral ovary in 86.2% of patients, compared with 81.0% using transvaginal sonography (P = 0.51). In addition, laparoscopic ultrasonography was able to demonstrate the presence of residual ovarian tissue in the side affected pathologically in 76.5% of patients compared with 59.4% using transvaginal sonography (P < 0.005). Laparoscopic sonography allows more precise morphologic characterization of internal architecture and histologic diagnosis of adnexal lesions, but it is as yet unable to increase the diagnostic accuracy of borderline or malignant lesions, possibly due to the small sample size. Laparoscopic sonography is superior to transvaginal sonography in the evaluation of residual ovarian tissue in the side affected pathologically, which may help in surgical planning between cystectomy and oophorectomy, and also in the identification of the contralateral ovary, which may potentially increase the detection of bilateral pathologic conditions.

Psychological factors and subclinical atherosclerosis in postmenopausal Chinese women in Hong Kong.

BACKGROUND Substantial evidence shows that psychological factors are associated with cardiovascular diseases. However, data on the association between psychological factors and subclinical atherosclerosis is lacking in postmenopausal Chinese women. OBJECTIVES To examine the associations of perceived stress and trait anxiety with subclinical atherosclerosis in postmenopausal Chinese women in Hong Kong. Their relationships with biological and behavioral risk factors were also examined. METHODS Between 2002 and 2004, we recruited 518 postmenopausal women aged 50-64 years. Perceived stress and trait anxiety were evaluated by the perceived stress scale and the state-trait anxiety inventory, respectively. Subclinical atherosclerosis was determined by measuring carotid intima-media thickness (IMT) and plaque using B-mode ultrasonography. RESULTS Perceived stress and trait anxiety showed no significant association with IMT or plaque. Multivariate analyses showed high perceived stress scores were associated with an increased risk of elevated total cholesterol (OR=2.10; 95% CI=1.17-3.77) and elevated low-density lipoprotein cholesterol (LDL-C) (OR=2.39; 95% CI=1.36-4.21). High trait anxiety scores were associated with a 2.7-fold risk of elevated LDL-C (OR=2.74; 95% CI=1.56-4.80). Women with high perceived stress or trait anxiety scores were more likely to be physically inactive. CONCLUSIONS Perceived stress and trait anxiety were associated with atherogenic lipid levels, but not subclinical atherosclerosis. Maintaining high physical activity may help alleviate psychological stress and anxiety.

Carotid atherosclerosis and the risk factors in early postmenopausal Chinese women.

OBJECTIVES To describe the distribution of intima-media thickness (IMT) and the prevalence of plaque by carotid segments, walls and sides, and to examine their associated risk factors in asymptomatic, early postmenopausal Chinese women in Hong Kong. METHODS Between 2002 and 2004, the study recruited 518 postmenopausal women aged 50-64 years. They were examined by B-mode ultrasound to measure the IMT and the prevalence of plaque at the near and far walls of common carotid (CCA), bifurcation (bulb), and internal carotid (ICA) of both the left and right carotid arteries. Blood pressures, obesity indices, lipids and glucose levels, sociodemographic, medical and lifestyle factors were also obtained. RESULTS The mean IMT was 0.76+/-0.12 mm (range: 0.53-1.33 mm). IMT was significantly thicker on the far wall than on the near wall and differed among segments (being thickest at the bulb and the narrowest at the ICA). 21.8% had at least one plaque in the carotid artery with most of the plaque found at the bulb area. Systolic blood pressure had statistically significant relationship with IMT that were fairly homogeneous among different segments. Lipids were associated with the CCA and bulb IMT, but not the ICA IMT. Diabetes predicted only CCA IMT. Older age, higher waist-hip-ratio and low-density lipoprotein cholesterol were significant predictors of plaques at all sites combined. CONCLUSIONS We described the distribution of IMT and the prevalence of plaque in asymptomatic, early postmenopausal Chinese women. Associations of risk factors with IMT of different arterial segments were also observed.

Color Velocity Imaging Quantification in the Detection of Intracranial Collateral Flow

Background and Purpose— The development of intracranial collateral circulation is associated with a lower risk of stroke. A noninvasive technique that can reliably detect the presence of intracranial collaterals would be a valuable factor in the assessment of risk in patients with occlusive cerebrovascular disease. Methods— Color velocity imaging quantification was used to measure the blood flow volume of the common carotid and vertebral arteries in 40 patients with carotid occlusive disease. The blood flow volumes in these arteries were correlated with angiographic evidence of collaterals to establish the best cutoffs for detecting intracranial collateral circulation. Results— A blood flow volume of either ≥370 mL/min in the common carotid artery or ≥120 mL/min in the vertebral artery was indicative of the presence of intracranial collaterals. The sensitivity and specificity for the common carotid artery were 92.3% [95% confidence interval (CI), 62.1 to 99.6] and 92.1% (95% CI, 77.5 to 97.9), respectively. The sensitivity and specificity for the vertebral artery were 75.0% (95% CI, 35.6 to 95.5) and 87.5% (95% CI, 66.5 to 96.7), respectively. Conclusions— Color velocity imaging quantification offers a noninvasive, accurate method for detecting the presence of intracranial collateral circulation and quantifying its magnitude. This technique would be a useful adjunct in screening or continuous monitoring of patients with severe carotid occlusive disease.

Transrectal ultrasound in the evaluation of cervical carcinoma and comparison with spiral computed tomography and magnetic resonance imaging

38 women with biopsy proven untreated cervical carcinoma were prospectively studied with transrectal ultrasound (TRUS), spiral computed tomography (SCT) and magnetic resonance imaging (MRI). 20 women had radical hysterectomy and pelvic lymphadenectomy with detailed histological evaluation of the parametra. The echographic features of cervical carcinoma on TRUS are a hypoechoic (60%) or isoechoic (40%) (relative to normal uterine muscle/cervical stroma), poorly defined mass lesion with indistinct margins in an enlarged cervix. This relatively high percentage of isoechoic tumours and relative lack of contrast resolution may pose a problem in the identification of some tumours, and to our knowledge has not been previously reported. Further limitations of TRUS are in the evaluation of advanced cervical cancer, due to bulky tumours rendering poor access to the parametrium and pelvic sidewall. The overall accuracy in staging of early cervical cancer (less than stage 2b) was 85% for examination under anaesthesia (EUA), 75% for TRUS, 65% for MRI and 50% for SCT. The positive predictive value in evaluating the parametra in this group of patients was also lower for SCT (14%) and MRI (33%) compared with TRUS (100%). In the evaluation of advanced cervical cancer (stage 2b or higher), there was poor correlation between TRUS and EUA, with MRI showing the best correlation with EUA. We conclude that SCT is inferior to both TRUS and MRI in the staging of early stage cervical cancer.