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Ma RCW, Lam CW, Chan WB, So WY, Tong SF, Chow CC, Cockram CS. A Chinese family with familial paraganglioma syndrome due to succinate dehydrogenase deficiency. Hong Kong Med J 2007; 13:151-4. [PMID: 17406045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2023] Open
Abstract
We report the genetic characteristics of a family with familial paraganglioma syndrome. The index patient was diagnosed with carcinoid tumour of the bronchus at the age of 30 years then later diagnosed with bilateral phaeochromocytoma. His sister had bilateral carotid body tumours. Mutational analyses of succinate dehydrogenase B and SDHD on the index patient showed him to be heterozygous for the M1I mutation of the SDHD gene. A genetic analysis revealed that his sister also had succinate dehydrogenase deficiency with the same mutation. Pre-symptomatic testing confirmed the genetic diagnosis, and led to a clinical diagnosis in an otherwise asymptomatic sibling. Comparison with other known cases of M1I mutation suggests that this is a founder mutation in the Chinese population. Genetic analysis of the succinate dehydrogenase genes can provide a specific diagnosis and allow for genetic screening of at-risk individuals.
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Lee RSY, Lam CW, Lai CK, Yuen YP, Chan KY, Shek CC, Chan AYW, Chow CB. Carnitine-acylcarnitine translocase deficiency in three neonates presenting with rapid deterioration and cardiac arrest. Hong Kong Med J 2007; 13:66-8. [PMID: 17277394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/13/2023] Open
Abstract
We report on three Chinese neonates with carnitine-acylcarnitine translocase deficiency. They presented within the first 48 hours of life. Two neonates were found in cardiac arrest; one of them survived after resuscitation. The third neonate suddenly developed cardiorespiratory insufficiency and succumbed eventually. The clustering of three cases in 5 years suggests that carnitine-acylcarnitine translocase deficiency is not rare in our Chinese population. We advocate that investigation for metabolic diseases including carnitine-acylcarnitine translocase deficiency should be performed in cases of sudden infant death and unexplained abrupt clinical deterioration in the early neonatal period. Non-ketotic hypoglycaemia is an early clue. The mainstay of initial treatment is glucose infusion at a rate greater than 7 mg/kg/minute, which inhibits beta-oxidation of fatty acids (the defective enzymatic steps in carnitine-acylcarnitine translocase deficiency) and thus prevents the accumulation of toxic long-chain acylcarnitines.
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Basheer SN, Waters PJ, Lam CW, Acquaviva-Bourdain C, Hendson G, Poskitt K, Hukin J. Isolated sulfite oxidase deficiency in the newborn: lactic acidaemia and leukoencephalopathy. Neuropediatrics 2007; 38:38-41. [PMID: 17607604 DOI: 10.1055/s-2007-981484] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
We report a newborn with progressive leukoencephalopathy and lactic acidaemia, diagnosed with isolated sulfite oxidase deficiency. We show that low plasma total homocysteine (PTHcy) is a valuable early indicator of sulfite oxidase dysfunction, providing a crucial first-line screen, whereas plasma cystine is not always informative in the first few days of life.
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Leung VKS, Law ST, Lam CW, Luk ISC, Chau TN, Loke TKL, Chan WH, Lam SH. Intestinal tuberculosis in a regional hospital in Hong Kong: a 10-year experience. Hong Kong Med J 2006; 12:264-71. [PMID: 16912352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023] Open
Abstract
OBJECTIVE To study the clinical and pathological characteristics of patients with intestinal tuberculosis. DESIGN Retrospective study. SETTING United Christian Hospital, Hong Kong. PATIENTS Patients with intestinal tuberculosis diagnosed between January 1995 and December 2004 inclusive. RESULTS The median age of the 13 male and 9 female patients was 53 years (range, 12-81 years). Nineteen (86%) had a definitive diagnosis of intestinal tuberculosis confirmed by the presence of caseating granulomas and/or acid-fast bacilli in histological specimens. In three (14%) the diagnosis was based on histology revealing non-caseating granulomas and a positive response to anti-tuberculous treatment. Common symptoms included abdominal pain (82%), diarrhoea (55%), weight loss (55%), and fever (45%). Three (14%) of the patients were complicated by intestinal obstruction, and another two (9%) had intestinal perforation. Four (18%) had concomitant active pulmonary tuberculosis. The most frequently involved site was the ileocaecal region, which was affected in 19 (86%) patients. Other sites included the jejunum, ascending and sigmoid colon. The diagnosis of intestinal tuberculosis was facilitated by examination of colonoscopic biopsy specimens (11 patients), and by examination of resected surgical specimens in the remainder. Two patients died from terminal malignancy. The remainder completed anti-tuberculous therapy and responded satisfactorily. CONCLUSIONS The diagnosis of intestinal tuberculosis is difficult due to the lack of specific signs or symptoms. Colonoscopy with ileoscopy are useful tools in the search for colonic and terminal ileal tuberculosis. Surgical exploration is reserved for equivocal cases and for those who present as emergencies.
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Yeung WL, Lam CW, Hui J, Tong SF, Wu SP. Galactorrhea-a strong clinical clue towards the diagnosis of neurotransmitter disease. Brain Dev 2006; 28:389-91. [PMID: 16376043 DOI: 10.1016/j.braindev.2005.10.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2005] [Revised: 09/26/2005] [Accepted: 10/14/2005] [Indexed: 11/26/2022]
Abstract
Two siblings from a Hong Kong Chinese family are diagnosed to have heterozygous mutation in tyrosine hydroxylase gene-a novel mutation R169X and the common Dutch mutation R233H. Presented with developmental delay and dystonia before 6 months of age, both had hyperprolactinemia with persistent galactorrhea present in the elder brother since birth. Serum prolactin level is a good screening test for those suspected of underlying neurotransmitter diseases. To our knowledge, this is the first Chinese family diagnosed with such condition. Clinicians must be aware of this rare disease especially in those unexplained 'cerebral palsy' like children.
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Mak CM, Tam S, Fan ST, Liu CL, Lam CW. Wilson's disease: a patient undiagnosed for 18 years. Hong Kong Med J 2006; 12:154-8. [PMID: 16603785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2023] Open
Abstract
Wilson's disease, an autosomal recessive disorder of copper metabolism, is the most common inherited hepatic disease in Hong Kong. Diagnosis is based on the presence of Kayser-Fleischer rings, typical neurological symptoms, and/or a low serum ceruloplasmin concentration (<0.20 g/L). Early detection and treatment protect patients and their presymptomatic siblings from devastating organ damage. The diagnosis of Wilson's disease may nonetheless be overlooked if only established clinical and laboratory tests are used as diagnostic criteria. We report diagnosis of the disorder using genetic analysis of ATP7B in a presymptomatic sibling who escaped diagnosis during family screening 18 years previously. The patient was 11 months old when family screening was performed following diagnosis of Wilson's disease in an elder sister. The boy was considered to be unaffected on the basis of laboratory results in the expected range: serum copper level, 4.6 micromol/L; serum ceruloplasmin level, 0.16 g/L; and 24-hour urinary copper excretion, 0.14 micromol/day. Molecular analysis of ATP7B was performed; it revealed that the two siblings shared the same compound heterozygous mutations (G943D and 2299delC). We recommend that molecular diagnosis is the only definitive means of diagnosing Wilson's disease in children younger than 1 year.
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Chan-yeung M, Yeh AGO, Tam CM, Kam KM, Leung CC, Yew WW, Lam CW. Socio-demographic and geographic indicators and distribution of tuberculosis in Hong Kong: a spatial analysis. Int J Tuberc Lung Dis 2005; 9:1320-6. [PMID: 16466053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/06/2023] Open
Abstract
OBJECTIVE To determine the socio-demographic and geographic indicators responsible for the distribution and transmission of tuberculosis (TB) in Hong Kong using geographical information system (GIS) technology. MATERIALS AND METHODS All patients with bacteriologically proven TB over a period of 3 years (May 1999-April 2002) residing within Hong Kong Island were studied. Molecular characterisation of their sputum isolates by IS6110-based restriction fragment length polymorphism (RFLP) technique was performed. Socio-demographic data were derived from the 2001 Hong Kong population census. Geographic coordinates of patients' addresses were linked to the GIS; large street block groups (LSBGs) were the units of analysis. RESULTS Of 2387 patients with bacteriologically confirmed TB, 2332 had valid addresses distributed in 430 LSBGs in Hong Kong Island. Of the five socio-demographic indicators studied, significant correlations were found between the rate of TB in an LSBG and low educational attainment, elderly population and low-income household, but not population density or unemployment. The five socio-demographic indicators were not different between LSBG with clustered cases and those with unique cases. CONCLUSION Low educational attainment, old age and poverty were significant determinants of the rate of TB in different parts of Hong Kong, while none of the socio-demographic indicators was related to disease transmission.
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Tam V, Ng KF, Fung LM, Wong YY, Chan MHM, Lam CW, Tam S, Lam CWK. The importance of the interpretation of urine catecholamines is essential for the diagnosis and management of patient with dopamine-secreting paraganglioma. Ann Clin Biochem 2005; 42:73-7. [PMID: 15802039 DOI: 10.1258/0004563053026916] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Phaeochromocytoma or paraganglioma that exclusively secretes dopamine is very rare. This case illustrates its atypical presentation and the importance of interpretative reporting for urine catecholamines leading to the diagnosis and subsequent management of a patient with this condition. We report a 71-year-old Chinese woman with a large dopamine-secreting paraganglioma. She presented with low back pain for six months. On examination, a right abdominal mass was palpable incidentally. Her blood pressure was normal throughout. Serial 24-h urine collections for catecholamines showed enormous elevation of urine dopamine excretion to 80.7 micromol/day (normotensive:<2.6 m mol/day). However, the daily excretions of urine adrenaline and noradrenaline, as well as their metabolites were within their respective reference intervals. Good communication between chemical pathologists and physicians prompted the arrangement of the whole body 131I-meta-iodobenzylguanidine (MIBG) scintigraphy, which showed a large signal in the right upper quadrant of the abdomen corresponding to a large extra-adrenal tumour detected by both ultrasonography and computerized tomography (CT) of the abdomen. Histological section of the tumour tissue revealed paraganglioma, which stained positive for chromogranin and neuron-specific enolase. After four months, the patient presented with chest symptoms and CT of the thorax revealed multiple nodules. Lung metastases were suspected. However, follow-up urine catechola- mine and dopamine excretions were again within their respective normotensive reference intervals. A second MIBG scintigraphy was performed, but no specific uptake at either the thorax or the abdomen could be demonstrated. Fine-needle aspiration cytology using the thoracoscopic technique was performed and immunochemical staining of the biopsy specimen showed the presence of non- small-cell carcinoma of the lung.
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Yeung WL, Lam CW, Cheng WT, Sin NC, Wong WK, Wong CN, Tse KM, Fok TF. Early-onset primary torsional dystonia in a 4-generation Chinese family with a mutation in the DYT1 gene. Chin Med J (Engl) 2005; 118:873-6. [PMID: 15989773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023] Open
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Kong APS, Lam CW, Chan AOK, Yiu SF, Tiu SC. Resistance to thyroid hormone in a Chinese family with R429Q mutation in the thyroid hormone receptor beta gene. Hong Kong Med J 2005; 11:125-9. [PMID: 15815068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2023] Open
Abstract
The combination of elevated serum levels of free thyroid hormones with non-suppressed thyroid-stimulating hormone suggests the differential diagnoses of resistance to thyroid hormone or thyroid-stimulating hormone-secreting pituitary tumour. Clinical differentiation of these two conditions can be difficult, because patients with thyroid hormone resistance may exhibit various combinations of hypermetabolic and hypometabolic features, and laboratory results have limited sensitivity and specificity. We report a case of resistance to thyroid hormone in a Chinese family that illustrates this difficulty. The diagnosis could only be confirmed by the identification of a known disease-causing mutation in the thyroid hormone receptor beta gene in peripheral leukocytes. Availability of genetic tests will identify more cases in the future and improve our understanding of this condition.
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Lam CW, Boey KW. The psychological well-being of the Chinese elderly living in old urban areas of Hong Kong: a social perspective. Aging Ment Health 2005; 9:162-6. [PMID: 15804634 DOI: 10.1080/13607860412331336823] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Using the Geriatric Depression Scale-15 (GDS-15) and the short form of the General Health Questionnaire-12 (GHQ-12), this study found that the Chinese elderly who live in old urban areas of Hong Kong are at risk of suffering from poor mental health because of their relatively deprived social conditions. It was also found that the respondent's scores in the GDS-15 correlated with their social conditions, including type of housing, availability of helpers, financial status and family support. However, Chinese elderly people often avoid seeking help because of the fear of being stigmatised. There is a need for more research in the future to study their needs and problems so that social work practitioners can be well informed and culturally competent to help this disadvantaged group.
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Yuen LK, Lam CW, Fong NC, Tang PM, Shek CC, Chan YW, Chow CB. Jervell-Lange Nielsen syndrome in a Pakistani family. Hong Kong Med J 2004; 10:351-4. [PMID: 15479966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/30/2023] Open
Abstract
Congenital long QT syndrome is a rare hereditary disease that is related to the dysfunction of ion channels in cardiac cells. We report on a very rare case of its autosomal recessive form--the Jervell-Lange Nielsen syndrome--in a Pakistani family, which was diagnosed after the incidental finding of bradycardia in a newborn baby girl. We discuss the range of presentations in neonates; the importance of strong suspicion of the syndrome and family screening; the use of the diagnostic criteria and genetic tests; and the different management strategies.
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Abstract
Home mechanical ventilation (HMV) is increasingly used to treat chronic respiratory failure. This present study was aimed to examine the trend, the disease categories treated and the outcomes of HMV use in Hong Kong. In the year 2002, all adult respiratory units in Hong Kong were invited to report to a multicentre retrospective survey of HMV use. A total of 249 patients (156 males, mean age 62.7 +/- 13.8 yrs) were treated since 1980, with 197 (79%) continuing with HMV at the time of the survey. Cumulative number of HMV grew as a cubic function of time since 1980. Currently, there are 2.9 users per 100,000 population. The predominant mode of HMV was noninvasive ventilation by bilevel pressure support ventilators (n=236). Chronic obstructive pulmonary disease accounted for 48.6% of all cases. The overall 3-yr HMV continuation rate was 66.2%. Death was the main reason for discontinuation. A rapidly rising trend of home mechanical ventilation use is observed in Hong Kong. In contrast to other series, chronic obstructive pulmonary disease was the major group treated and bilevel pressure support ventilation was the predominant mode chosen. Most patients tolerate home mechanical ventilation reasonably well, with approximately two-thirds continuing with its use at 36 months.
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Li SSL, Lam CW, So YC, Wong CH, Yiu SF, Ho D, Chan KW, Chan KT. The use of a distal occlusion balloon protection device in acute coronary syndrome. Int J Cardiol 2003; 92:281-4. [PMID: 14659866 DOI: 10.1016/s0167-5273(03)00097-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
We report our early experience in using the PercuSurge GuardWire Plus system as a distal protection device in patients with acute coronary syndrome and acute myocardial infarction. Forty-three patients received percutaneous coronary intervention with the GuardWire Plus system. Thirteen had unstable angina, five had non-Q myocardial infarction and 25 had ST segment elevation myocardial infarction. Forty-one target lesions were in native coronary vessels and two were in saphenous vein grafts. Total occlusion occurred in 18 patients. The mean occlusion time by the distal protective balloon was 262.8 +/- 114.1 s. Preoperatively, TIMI 0 flow was present in 18, TIMI II flow in two and TIMI III flow in 23 patients. Post-operatively, TIMI II and TIMI III flow were established in two and 41 patients, respectively. All procedures were successful and the GuardWire Plus system was successfully deployed in all but two patients. There was no procedure-related major adverse clinical event. There was no major adverse clinical event at 30 days. There was no device-related complication. We believe that the GuardWire Plus system is safe and feasible in patients with acute coronary syndrome and acute myocardial infarction.
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Li CH, Lam CW, Lee CWA, Kwong NS, Szeto SC. Pearson's syndrome: a rare cause of non-immune hydrops fetalis. Chin Med J (Engl) 2003; 116:1952-4. [PMID: 14986619 DOI: pmid/14986619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
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Leung CC, Yew WW, Chan CK, Tam CM, Lam CW, Chang KC, Chau CH, Lau KS, Law WS. Smoking and tuberculosis in Hong Kong. Int J Tuberc Lung Dis 2003; 7:980-6. [PMID: 14552569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/27/2023] Open
Abstract
OBJECTIVE To study the relationship between smoking and tuberculosis in Hong Kong. METHOD Indirect sex and age adjustment was used to compare the prevalence of ever smokers between a sample of 851 patients from the 1996 tuberculosis notification registry and the general population. The clinical characteristics of smokers and non-smokers were compared by stratified univariate analysis and multiple logistic regression. RESULTS Tuberculosis patients were more likely to have smoked than population controls. The respective odds ratios for ever smoking between tuberculosis patients and population controls were 2.44 and 2.08 for males and females aged 16-64 (Mantel-Haenszel weighted OR = 2.40, P < 0.001), and 2.09 and 2.83 for males and females aged > or = 65 (Mantel-Haenszel weighted odds ratio = 2.19, P < 0.001). Male sex, age > or = 65, working at onset of illness, regular alcohol use, drug abuse and absence of contact history were associated with ever smokers (all P < 0.05). Ever smokers were more likely to have cough (OR 1.69), dyspnoea (OR 1.84), upper zone involvement (OR 1.67), cavity (OR 1.76), miliary lung involvement (OR 2.77), positive sputum culture (OR 1.43), but less isolated extrathoracic involvement (OR 0.31), even after controlling for the confounding background variables (all P < 0.05). CONCLUSION There was a consistent association between smoking and tuberculosis. More aggressive lung involvement was also found among ever smokers.
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Ng MHL, Lau KM, Wong WS, To KW, Cheng SH, Tsang KS, Chan NPH, Kho BCS, Lo KW, Tong JHM, Lam CW, Chan JCW. Frequent RASSF1A promoter hypermethylation and K-ras mutations in pancreatic carcinoma. Oncogene 2003; 123:637-45. [PMID: 14616967 DOI: 10.1046/j.1365-2141.2003.04664.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Recently, we have characterized the Ras association domain family 1A gene (RASSF1A) at the segment 3p21.3, which is frequently lost in variety of human cancers and epigenetically inactivated in many types of primary tumors, such as lung, breast, kidney, prostate and thyroid carcinomas. Here, we investigated the methylation status of the RASSF1A CpG island promoter in the pathogenesis of pancreatic cancer. RASSF1A hypermethylation was detected in 29 out of 45 (64%) primary adenocarcinomas, in 10 out of 12 (83%) endocrine tumors and in eight out of 18 (44%) pancreatitis samples. In seven out of eight pancreas cancer cell lines, RASSF1A was silenced and was retranscribed after treatment with 5-aza-2'-deoxycytidine. Additionally, we analysed the aberrant methylation frequency of cell cycle inhibitor p16(INK4a) and K-ras gene mutations in the pancreatic samples. p16 inactivation was detected in 43% of adenocarcinomas, in 17% of neuroendocrine tumors, in 18% of pancreatitis and in 63% of pancreas cancer cell lines. K-ras mutations were detected in 16 out of 45 (36%) primary adenocarcinomas. Pancreatic adenocarcinomas with K-ras mutation have significantly less RASSF1A methylation and vice versa (P=0.001, chi(2) test). In conclusion, our data indicate that inactivation of the RASSF1A gene is a frequent event in pancreatic cancer and suggest an inverse correlation between RASSF1A silencing and K-ras activation.
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Mak CM, Lam CW, Fan ST, Liu CL, Tam SC. Genetics of familial amyloidotic polyneuropathy in a Hong Kong Chinese kindred. Acta Neurol Scand 2003; 107:419-22. [PMID: 12757474 DOI: 10.1034/j.1600-0404.2003.00047.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Familial amyloidotic polyneuropathy type 1 (FAP1, MIM176300) is an autosomal dominant disease caused by mutations in the transthyretin (TTR) gene. An extended Chinese kindred of FAP1 was first reported in Hong Kong in 1989, three of the four histologically proven subjects have deceased. TTR gene mutations were not studied then. A DNA-based diagnosis was performed on FAP1 by restriction analysis and direct DNA sequencing was carried out on a symptomatic member of this family who had undergone a liver transplantation. It showed a substitution of thymine by cytosine in the second base of codon 30 in exon 2 of the TTR gene, with the creation of a novel HhaI restriction endonuclease site. Valine is substituted by alanine (V30A) in the mutant TTR. Both restriction analysis and direct sequencing revealed the same mutation in one of the two asymptomatic siblings. This mutation was first reported in a FAP1 family of German descent.
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Chan MHM, Chow KM, Chan ATC, Leung CB, Chan LYS, Chow KCK, Lam CW, Lo YMD. Quantitative analysis of pleural fluid cell-free DNA as a tool for the classification of pleural effusions. Clin Chem 2003; 49:740-5. [PMID: 12709364 DOI: 10.1373/49.5.740] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Recently, much interest has been focused on the quantification of DNA in miscellaneous body fluids. In this study, the application is extended to classifying pleural effusions by measuring cell-free DNA in pleural fluid. METHODS We recruited 50 consecutive patients with pleural effusions with informed consent. Pleural fluids were centrifuged at 13000 g, with supernatants aliquoted for extraction and analysis of beta-globin DNA sequence by quantitative real-time PCR. Serum and pleural fluid biochemistries were performed to classify pleural effusions using the modified criteria of Light et al. (Ann Intern Med 1972;77:507-13). The ROC curve was plotted to determine the cutoff DNA concentration for classifying pleural fluids as transudates or exudates. Indicators of diagnostic accuracy were calculated for both pleural fluid DNA and modified criteria of Light et al., using the discharge, microbiologic, and histologic diagnoses as the reference standard. RESULTS The area under the ROC curve was 0.95 [95% confidence interval (CI), 0.84-0.99]. At 509 genome-equivalents/mL, pleural fluid DNA alone correctly classified 46 of 50 pleural effusions with 91% sensitivity (95% CI, 76-98%), 88% specificity (95% CI, 64-98%), and positive and negative likelihood ratios of 7.7 (95% CI, 3.1-19.5) and 0.10 (95% CI, 0.04-0.27), respectively. With the modified criteria of Light et al., 43 of 50 pleural effusions were correctly classified with 97% sensitivity (95% CI, 91-100%) and 67% specificity (95% CI, 45-89%). There were significant correlations between cell-free DNA and both lactate dehydrogenase and total protein in pleural fluid, suggesting their common origin. CONCLUSIONS Pleural fluid DNA concentrations are markedly increased in exudative effusions, making it a potential new tool to evaluate the etiologic causes of pleural effusions.
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Au KM, Lai CK, Yuen YP, Shek CC, Lam CW, Chan AYW. Diagnosis of dihydropyrimidine dehydrogenase deficiency in a neonate with thymine-uraciluria. Hong Kong Med J 2003; 9:130-2. [PMID: 12668826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023] Open
Abstract
Dihydropyrimidine dehydrogenase deficiency is an inborn error of pyrimidine metabolism characterised by thymine-uraciluria, convulsive disorders and developmental delay in paediatric patients, and an increased risk of toxicity from 5-fluorouracil treatment. This report is of the first patient with dihydropyrimidine dehydrogenase deficiency diagnosed in Hong Kong. The patient was a 2-day-old male neonate of Pakistani origin who presented with convulsions. Diagnosis was made by gas chromatographic-mass spectrometric detection of thymine-uraciluria and by molecular detection of a G to A point mutation in a 5'-splicing site leading to skipping of exon 14 in the DPYD gene of chromosome location 1q22. The results showed that the patient and his mother were homozygous and the father heterozygous for the splice site mutation. The mother also had thymine-uraciluria but was clinically asymptomatic.
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Lam CW, Yuen YP, Chan KY, Tong SF, Lai CK, Chow TC, Lee KC, Chan YW, Martiniuk F. Juvenile-onset glycogen storage disease type II with novel mutations in acid alpha-glucosidase gene. Neurology 2003; 60:715-7. [PMID: 12601120 DOI: 10.1212/01.wnl.0000048661.95327.bf] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The authors describe two novel mutations of the acid alpha-glucosidase gene, P361L and R437C, which define the juvenile-onset glycogen storage disease type II (GSDII) in a 16-year-old Chinese patient. The asymptomatic 13-year-old brother of the proband is also a compound heterozygote of the two mutations. These results confirm that intrafamilial phenotypic variation of juvenile-onset GSDII is ethnically diverse and suggest the contribution of other genes to the phenotypic variability of GSDII.
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Kumana CR, Au WY, Lee NSL, Kou M, Mak RWM, Lam CW, Kwong YL. Systemic availability of arsenic from oral arsenic-trioxide used to treat patients with hematological malignancies. Eur J Clin Pharmacol 2002; 58:521-6. [PMID: 12451429 DOI: 10.1007/s00228-002-0514-x] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2002] [Accepted: 08/22/2002] [Indexed: 10/27/2022]
Abstract
AIMS Arsenic trioxide (As2O3) is increasingly used to treat hematological malignancies. This involves daily intravenous (i.v.) administration for 4-8 weeks, with its attendant drawbacks: inconvenience, risks and expense of maintaining suitable vascular access and hospitalization. We therefore developed an oral formulation, administered it to patients and set out to assess the resulting systemic bioavailability of arsenic. METHODS With ethics committee approval, nine patients with refractory/relapsed acute myeloid leukemia were recruited after giving informed consent. On day 1, each received 10 mg As2O3 by i.v. infusion over 1 h. Each patient swallowed 10 mg As2O3 in 10 ml oral solution 24 h later (day 2) and on subsequent days thereafter. Prior to and until 48 h post-i.v. dosing, timed venous blood samples were drawn and corresponding plasma and whole blood arsenic concentrations were determined by atomic absorption spectroscopy. Systemic bioavailability was inferred from the area under the arsenic level versus time curve (AUC) using the trapezoidal rule. Day-1 AUC after i.v. dosing was taken to be 100% and that attributed to oral dosing (day 2) was then calculated. The 48-h arsenic levels in blood cells were calculated using hematocrit values and corresponding plasma and whole blood arsenic concentrations. RESULTS Respective day-2 mean plasma and blood AUCs attributed to oral dosing were 99% and 87% of corresponding day-1 values. On average, 48-h blood cell arsenic levels were 270% greater than in plasma ( P=0.013). No patient suffered unexpected complications, and five went into remission. CONCLUSIONS Compared with i.v. dosing, our oral As2O3 formulation was more convenient and cost effective, and the ensuing systemic bioavailability of arsenic appeared similar. Arsenic seemed to be concentrated in the cellular fraction of blood 48 h after starting As2O3 treatment.
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Chan PKS, Lam CW, Cheung TH, Li WWH, Lo KWK, Chan MYM, Cheung JLK, Xu LY, Cheng AF. Human papillomavirus type 16 intratypic variant infection and risk for cervical neoplasia in southern China. J Infect Dis 2002; 186:696-700. [PMID: 12195358 DOI: 10.1086/342048] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2002] [Revised: 04/19/2002] [Indexed: 11/03/2022] Open
Abstract
A case-control study was conducted on 1986 Hong Kong women to assess the risk of human papillomavirus (HPV) type 16 variants for cervical neoplasia. In total, 255 women were HPV-16 positive and were analyzed for E6 and E7 sequence variation. Two novel substitutions at E6 (T86I and Q116E) and 1 at E7 (R66W) were found. Most HPV-16 variants were of Asian (50.6%) or European (44.3%) lineage, and both lineages showed similar risk associations for high-grade and invasive cervical neoplasia. No increased risk was observed for the subclasses European variant and European 350G, which carry a higher risk for invasive cancer in some Western populations. The E7 N29S substitution, reported to have a higher risk in Korean women, was found equally distributed among normal and various degrees of neoplasia. The epidemiology and risk implication of HPV-16 variant infection in Hong Kong differ markedly from other parts of the world.
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Chiu RWK, Ho CS, Tong SF, Ng KF, Lam CW. Evaluation of a new handheld biosensor for point-of-care testing of whole blood beta-hydroxybutyrate concentration. Hong Kong Med J 2002; 8:172-6. [PMID: 12055361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023] Open
Abstract
OBJECTIVES To evaluate performance characteristics of the newly available handheld combined glucose and ketone meter for beta-hydroxybutyrate measurement. DESIGN Laboratory method evaluation. MAIN OUTCOME MEASURES Accuracy of beta-hydroxybutyrate measurement and effect of acetoacetate interference at clinically important beta-hydroxybutyrate levels. RESULTS Deming regression analysis of beta-hydroxybutyrate measurements assessed by the ketone sensor and a laboratory enzymatic method revealed a coefficient of determination of 0.989 (P<0.001). Passing-Bablok regression analysis showed a linear relationship between the two methods, ie Y= -0.32+1.13X. The 95% confidence interval of the slope and y-intercept were: slope=1.13 (95% confidence interval, 1.04 to 1.22); intercept= -0.32 (95% confidence interval, -0.59 to -0.06). The Bland-Altman plot showed a small proportional bias between the two methods. The mean bias +/-2 standard deviations was between -0.53 and 0.67 mmol/L. Beta-hydroxybutyrate measurements made by the sensor were linear up to 6 mmol/L. Replicate analysis of two samples spiked with 3.6 mmol/L and 0.8 mmol/L of beta-hydroxybutyrate resulted in coefficients of variation of 3.3% and 13%, respectively. The presence of acetoacetate caused a negative interference in beta-hydroxybutyrate measurement. Beta-hydroxybutyrate recovery was 97.0% and 90.7% when the ketone body ratios were 6:1 and 3:1, respectively. CONCLUSION The analytical performance of the sensor, when operated according to manufacturer's instructions, could meet the needs of point-of-care beta-hydroxybutyrate measurement. Additional clinical studies are needed to assess the benefits of introducing such an assay in a clinical setting.
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McGrath C, Liu KS, Lam CW. Physiognomy and teeth: an ethnographic study among young and middle-aged Hong Kong adults. Br Dent J 2002; 192:522-5. [PMID: 12047124 DOI: 10.1038/sj.bdj.4801417] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVES To determine knowledge and beliefs about traditional physiognomy (judging an individual's character from their facial appearance) concerning teeth among young (17-26) and middle-aged (35-44) Hong Kong adults. METHODS In a cross sectional ethnographical telephone survey, 400 adults were interviewed about 16 traditional physiognomy concerning teeth (in consultation with a Feng Shui specialist). RESULTS Most completed the interview (93%, 373). Over half the study group (63%, 234) claimed they had heard of aspects of physiognomy concerning teeth, and a quarter (24%, 88) believed in such ideologies. Variations in knowledge and beliefs were apparent among people of different age (P < 0.01), gender (P < 0.05), educational attainment (P < 0.01), economic status (P < 0.01), place of birth (P < 0.01) and religion (P < 0.01). Their knowledge and belief in aspects of physiognomy concerning teeth was also associated with reported use of dental services (P < 0.01). CONCLUSION Among young and middle-aged adults in Hong Kong, knowledge and beliefs concerning traditional physiognomy regarding teeth is strong, and socio-demographic variations exist in these perceptions. These findings have implications for all those involved in the delivery of dental care in multicultural societies and in raising cultural awareness about traditional health beliefs.
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