BACKGROUNDObstetric anal sphincter injuries (OASIS) can cause an adverse impact on women's physical and mental health. There was lack of published data in Chinese population particularly on studying the risk of OASIS for nonrotational outlet forceps. This study was to determine the incidence and risk factors of OASIS.

METHODSThis is a retrospective cohort study carried out in a tertiary referral hospital in Hong Kong. The control group was selected randomly. Univariate and multivariate logistic regression analysis was performed to evaluate the influence of potential risk factors on OASIS. This study reviewed the obstetric records of OASIS women and random control from January 2011 to June 2014. Univariate and multivariate logistic regression analysis was performed to evaluate the influence of potential risk factors on OASIS.

RESULTSOf 15,446 women delivered, 49 had OASIS. The percentage of OASIS increased from 0.3% (2011) to 0.38% (2014). There was an increasing trend of OASIS in attempted spontaneous vaginal delivery without episiotomy (P < 0.01), but it did not increase the OASIS risk (P = 0.46). Univariate analysis of 49 cases and 438 control subjects showed that forceps delivery (odds ratio [OR] =8.73, P < 0.01), prolong second stage of labor (OR = 1.43, P < 0.01) increased the risk for OASIS. In multivariate regression models, only forceps delivery (OR = 6.28, P < 0.01) proved to be independent risk factor.

CONCLUSIONSThe incidence of OASIS in Chinese women was increased after 2012, but still lower than the reported figures in the literature. Outlet forceps delivery could be a possible associated risk factor.

Adult ; Anal Canal ; injuries ; Delivery, Obstetric ; adverse effects ; Female ; Hong Kong ; epidemiology ; Humans ; Incidence ; Lacerations ; epidemiology ; etiology ; Multivariate Analysis ; Obstetric Labor Complications ; epidemiology ; etiology ; Pregnancy ; Retrospective Studies ; Risk Factors

BACKGROUNDChildhood cancer survivors were at risk of development of second malignant neoplasms. The aim of this study is to evaluate the incidence, risk factors and outcome of second malignant neoplasms in childhood cancer survivors in a tertiary paediatric oncology centre in Hong Kong, China.

METHODSWe performed a retrospective review of patients with childhood cancer treated in Children's Cancer Centre in Prince of Wales Hospital, Hong Kong, China between May 1984 and June 2009. Case records of patients who developed second malignant neoplasms were reviewed.

RESULTSTotally 1374 new cases aged less than 21-year old were treated in our centre in this 25-year study period. Twelve cases developed second malignant neoplasms with 10-year and 20-year cumulative incidence of 1.3% (95% confidence interval 0.3% - 2.3%) and 2.9% (95% confidence interval 1.1% - 4.7%) respectively. Another 4 cases were referred to us from other centres for the management of second malignant neoplasms. In this cohort of 16 children with second malignant neoplasms, the most frequent second malignant neoplasms were acute leukemia or myelodysplastic syndrome (n = 6) and central nervous system tumor (n = 4). Median interval between diagnosis of primary and second malignant neoplasms was 7.4 years (range 2.1 - 13.3 years). Eight patients developed second solid tumor within the previous irradiated field. Radiotherapy significantly increased the risk of development of second solid tumor in patients with acute lymphoblastic leukemia (P = 0.027). Seven out of 16 patients who developed second malignant neoplasms had a family history of cancer among the first or second-degree relatives. Nine patients died of progression of second malignant neoplasms, mainly resulted from second central nervous system tumor and osteosarcoma.

CONCLUSIONSCumulative incidence of second cancer in our centre was comparable to western countries. Radiotherapy was associated with second solid tumour among patients with acute lymphoblastic leukemia. Patients who developed second brain tumor and osteosarcoma had a poor outcome.

Adolescent ; Adult ; Child ; Child, Preschool ; China ; epidemiology ; Female ; Hong Kong ; epidemiology ; Humans ; Infant ; Infant, Newborn ; Male ; Neoplasms ; epidemiology ; Neoplasms, Second Primary ; epidemiology ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; Retrospective Studies ; Survivors ; statistics & numerical data ; Young Adult

BACKGROUNDProactive infection control management is crucial in preventing the introduction of multiple drug resistant organisms in the healthcare setting. In Hong Kong, where vancomycin-resistant enterococci (VRE) endemicity is not yet established, contact tracing and screening, together with other infection control measures are essential in limiting intra- and inter-hospital transmission. The objective of this study was to illustrate the control measures used to eradicate a VRE outbreak in a hospital network in Hong Kong.

METHODSWe described an outbreak of VRE in a healthcare region in Hong Kong, involving a University affiliated hospital and a convalescent hospital of 1600 and 550 beds respectively. Computer-assisted analysis was utilized to facilitate contact tracing, followed by VRE screening using chromogenic agar. Multi-locus sequence typing (MLST) was performed to assess the clonality of the VRE strains isolated. A case-control study was conducted to identify the risk factors for nosocomial acquisition of VRE.

RESULTSBetween November 26 and December 17, 2011, 11 patients (1 exogenous case and 10 secondary cases) in two hospitals with VRE colonization were detected during our outbreak investigation and screening for 361 contact patients, resulting in a clinical attack rate of 2.8% (10/361). There were 8 males and 3 females with a median age of 78 years (range, 40 - 87 years). MLST confirmed sequence type ST414 in all isolates. Case-control analysis demonstrated that VRE positive cases had a significantly longer cumulative length of stay (P < 0.001), a higher proportion with chronic cerebral and cardiopulmonary conditions (P = 0.001), underlying malignancies (P < 0.001), and presence of urinary catheter (P < 0.001), wound or ulcer (P < 0.001), and a greater proportion of these patients were receiving β-lactam/β-lactamase inhibitors (P = 0.009), carbapenem group (P < 0.001), fluoroquinolones (P = 0.003), or vancomycin (P = 0.001) when compared with the controls.

CONCLUSIONExtensive contact tracing and screening with a "search-and-confine" strategy was a successful tool for outbreak control in our healthcare region.

Aged ; Aged, 80 and over ; Enterococcus faecium ; growth & development ; pathogenicity ; Female ; Gram-Positive Bacterial Infections ; epidemiology ; prevention & control ; Hong Kong ; epidemiology ; Humans ; Male ; Middle Aged ; Vancomycin Resistance

OBJECTIVETo investigate the relationship between silica or silicosis and lung cancer in a large cohort of silicotic workers in Hong Kong.

METHODSAll workers with silicosis in Hong Kong diagnosed between 1981 and 1998 were followed up till the end of 1999 to ascertain their vital status and causes of death, using the corresponding mortality rates of Hong Kong males of the same period as external comparison. Standardized mortality ratios (SMR) for lung cancer and other major causes of death were calculated. Person-year method was used. Axelson's indirect method was performed to adjust for the confounding effect of smoking. Penalized smoothing spline (p-spline) models were used to evaluate the exposure-response relationship between silica dust exposure and lung cancer mortality.

RESULTSA total of 2789 newly diagnosed cases of silicosis were included in the cohort, with an overall 24 992.6 person-years of observations. The loss-to-follow-up rate was only 2.9%. Surface construction workers (51%) and underground caisson workers (37%) constituted the major part of the cohort. There were 853 silicotics observed with an average age at death of 63.8 years. The SMR for all causes and all cancers increased significantly. The leading cause of death was non-malignant respiratory diseases. About 86 deaths were from lung cancer, giving a SMR of 1.69 (95% CI: 1.35 approximately 2.09). The risk of lung cancer death among workers in surface construction, underground caisson, and entire cohort was reduced to 1.12 (95% CI: 0.89 approximately 1.38), 1.09 (95% CI: 0.82 approximately 1.42) and 1.56 (95% CI: 0.98 approximately 2.36) respectively, after indirectly adjusting for smoking.

RESULTSfrom P-spline model did not show a clear exposure-response relationship between silica dust (CDE and MDC) and lung cancer mortality.

CONCLUSIONThis cohort study did not show an increased risk of lung cancer mortality among silicotic workers. P-spline model does not support an exposure-response relationship between silica dust exposure and lung cancer mortality.

Adult ; Aged ; Dust ; Follow-Up Studies ; Hong Kong ; epidemiology ; Humans ; Lung Neoplasms ; etiology ; mortality ; Male ; Middle Aged ; Occupational Exposure ; adverse effects ; Retrospective Studies ; Silicosis ; complications ; mortality

BACKGROUNDIdentification of hospitalized carbapenem-resistant Enterobacteriaceae (CRE)-positive patient is important in preventing nosocomial transmission. The objective of this study was to illustrate the implementation of proactive infection control measures in preventing nosocomial transmission of CRE in a healthcare region of over 3200 beds in Hong Kong between October 1, 2010 and December 31, 2011.

METHODSThe program included active surveillance culture in patients with history of medical tourism with hospitalization and surgical operation outside Hong Kong within 12 months before admission, and "added test" as an opportunistic CRE screening in all fecal specimens submitted to the laboratory. Outbreak investigation and contact tracing were conducted for CRE-positive patients. Serial quantitative culture was performed on CRE-positive patients and the duration of fecal carriage of CRE was analyzed.

RESULTSDuring the study period, a total of 6533 patients were screened for CRE, of which 76 patients were positive (10 from active surveillance culture, 65 from "added test", and 1 secondary case from contact tracing of 223 patients with no nosocomial outbreak), resulting in an overall rate of CRE fecal carriage of 1.2%. The median time of fecal carriage of CRE was 43 days (range, 13-119 days). Beta-lactam-beta-lactamase-inhibitors, cephalosporins, and fluoroquinolones were associated significantly with high fecal bacterial load when used 90 days before CRE detection, while use of cephalosporins, carbapenems, and fluoroquinolones after CRE detection are significantly associated with longer duration of carriage. The duration of fecal carriage of CRE also correlates significantly with the initial fecal bacterial load (Pearson correlation: 0.53; P = 0.02).

CONCLUSIONProactive infection control measures by enhanced surveillance program identify CRE-positive patients and data obtained are useful for the planning of and resource allocation for CRE control.

Anti-Bacterial Agents ; therapeutic use ; Carbapenems ; therapeutic use ; Cephalosporins ; therapeutic use ; Drug Resistance, Bacterial ; Enterobacteriaceae ; drug effects ; Enterobacteriaceae Infections ; prevention & control ; transmission ; Fluoroquinolones ; therapeutic use ; Humans ; Infection Control ; methods

PURPOSE: The aims of this study were to investigate the prevalence of upper tract involvement in ketamine-associated uropathy, and to determine the predictors of hydronephrosis in patients with a history of ketamine abuse. METHODS: This was a cross-sectional study of a prospective cohort of patients with ketamine-associated uropathy. Data including demographics, pattern of ketamine abuse, pelvic pain and urgency or frequency (PUF) symptom score, uroflowmetry (UFM) parameters, serum renal function, and liver function tests were collected. Upon consultation, ultrasonography was performed to assess the function of the urinary system. RESULTS: From December 2011 to October 2015, we treated 572 patients with ketamine-associated uropathy. Of these patients, 207 (36.2%) had managed to achieve abstinence at the time of their first consultation. Ninety-six patients (16.8%) in the cohort were found to have hydronephrosis on ultrasonography. Univariate analysis identified age, duration of ketamine abuse, PUF symptom score, voided volume on UFM, serum creatinine levels >100 μmol/L, and an abnormal serum liver enzyme profile as factors associated with hydronephrosis. Logistic regression revealed the following parameters to be statistically related to hydronephrosis: age (adjusted odds ratio [OR], 1.090; 95% confidence interval [CI], 1.020–1.166; P=0.012), functional bladder capacity (adjusted OR, 0.997; 95% CI, 0.995–0.999; P=0.029), serum creatinine >100 μmol/L (adjusted OR, 3.107; 95% CI, 1.238–7.794; P=0.016, and an abnormal serum liver enzyme profile (adjusted OR, 1.967; 95% CI, 1.213–3.187; P=0.006). CONCLUSIONS: Ketamine-associated uropathy can involve the upper urinary tract. Patient demographics as well as investigations of UFM, renal function tests, and liver function tests may allow us to identify at-risk patients.
Cohort Studies ; Creatinine ; Cross-Sectional Studies ; Cystitis ; Demography ; Humans ; Hydronephrosis ; Ketamine ; Liver ; Liver Function Tests ; Logistic Models ; Lower Urinary Tract Symptoms ; Odds Ratio ; Pelvic Pain ; Prevalence ; Prospective Studies ; Ultrasonography ; Urinary Bladder ; Urinary Tract* ; Urination Disorders

BACKGROUNDData of classical inborn errors of metabolism (IEM) of amino acids, organic acids and fatty acid oxidation are largely lacking in Hong Kong, where mass spectrometry-based expanded newborn screening for IEM has not been initiated. The current study aimed to evaluate the approximate incidence, spectrum and other characteristics of classical IEM in Hong Kong, which would be important in developing an expanded newborn screening program for the local area.

METHODSThe laboratory records of plasma amino acids, plasma acylcarnitines and urine organic acids analyses from year 2005 to 2009 inclusive in three regional chemical pathology laboratories providing biochemical and genetic diagnostic services for IEM were retrospectively reviewed.

RESULTSAmong the cohort, 43 patients were diagnosed of IEM, including 30 cases (69%) of amino acidemias (predominantly citrin deficiency, hyperphenylalaninemia due to 6-pyruvoyl-tetrahydropterin synthase deficiency and tyrosinemia type I), 5 cases (12%) of organic acidemias (predominantly holocarboxylase synthetase deficiency) and 8 cases (19%) of fatty acid oxidation defects (predominantly carnitine-acylcarnitine translocase deficiency). The incidence of classical IEM in Hong Kong was roughly estimated to be at least 1 case per 4122 lives births, or 0.243 cases per 1000 live births. This incidence is similar to those reported worldwide, including the mainland of China. The estimated incidence of hyperphenylalaninemia was 1 in 29 542 live births.

CONCLUSIONSOur data indicate that it is indisputable for the introduction of expanded newborn screening program in Hong Kong. Since Hong Kong is a metropolitan city, a comprehensive expanded newborn screening program and referral system should be available to serve the neonates born in the area.

Acids ; urine ; Amino Acids ; blood ; Carnitine ; analogs & derivatives ; blood ; Hong Kong ; epidemiology ; Humans ; Infant, Newborn ; Metabolism, Inborn Errors ; blood ; diagnosis ; epidemiology ; urine ; Neonatal Screening ; methods ; Tandem Mass Spectrometry

OBJECTIVETo investigate the efficacy of a herbal formula in the prevention of influenza or influenza-like syndrome among elderies residing in old-people's home in Hong Kong. The secondary objectives are to investigate the quality of life (QOL) and symptomology changes among the herbal users and to evaluate the safety of this formula.

METHODSIn ten old people's home or community centres in New Territories, Hong Kong, 740 eligible subjects agreed to join the study and were randomized to receive a herbal formula or a placebo on alternate days over 8 weeks. Among those 740 participants, 113 had provided blood samples for immunological assessments before and after the study drug. Assessments were done at 0, 4, 8 and 12 weeks. Participants were instructed to keep a daily record of body temperature and any symptoms as sore throat, myalgia, running nose or cough, and to report to assessor accordingly. Those reporting body temperature of 37.8 °C and above would be visited and a proper nasopharyngeal swab be taken for viral study.

RESULTSSeventy-two participants developed influenza-like-symptoms but none of them was proven influenza in their nasopharyngeal swabs, 40 of these patients belonged to the herbal group and 32 to the placebo group, without significant differences between groups. The difference on the changes in QOL between the two groups was not statistically significant. However, in the immunological study, the natural killer cell absolute count was significantly increased in the herbal group compared with the placebo group (463 ± 253 vs 413 ± 198, P<0.05).

CONCLUSIONSThe herbal preparation was not effective compared with placebo in the prevention of influenza-like syndrome. It was however safe and possibly supporting immunological responses.

Aged ; Demography ; Double-Blind Method ; Drugs, Chinese Herbal ; adverse effects ; therapeutic use ; Female ; Humans ; Immunologic Tests ; Influenza, Human ; drug therapy ; immunology ; prevention & control ; Male ; Quality of Life ; Vaccination