Rapid antigen test during a COVID-19 outbreak in a private hospital in Hong Kong.

INTRODUCTION: In response to two nosocomial clusters of coronavirus disease 2019 (COVID-19) in our hospital, we adopted a series of strict infection control measures, including regular rapid antigen test (RAT) screening for high-risk patients, visitors, and healthcare workers. We evaluated the diagnostic performance of a locally developed RAT, the INDICAID COVID-19 Rapid Antigen Test (Phase Scientific, Hong Kong), using respiratory samples from both symptomatic and asymptomatic individuals. METHODS: Real-time reverse-transcription polymerase chain reaction (rRT-PCR)-confirmed deep throat saliva (DTS) and pooled nasopharyngeal swab and throat swab (NPS/TS) samples collected from 1 November to 30 November 2020 were tested by INDICAID. Screening RATs were performed on asymptomatic healthcare workers during a 16-week period (1 December 2020 to 22 March 2021). RESULTS: In total, 20 rRT-PCR-confirmed samples (16 DTS, four pooled NPS/TS) were available for RAT. Using the original sample, RAT results were positive in 17/20 samples, indicating 85% sensitivity (95% confidence interval [CI]=62.11%-96.79%). Negative RAT results were associated with higher cycle threshold (Ct) values. For samples with Ct values <25, the sensitivity was 100%. Of the 49 801 RATs collected from healthcare workers, 33 false positives and one rRT-PCR-confirmed case were detected. The overall specificity was 99.93% (95% CI=99.91%-99.95%). The positive and negative predictive values were 2.94% (95% CI=2.11%-4.09%) and 100%, respectively. CONCLUSION: The INDICAID COVID-19 RAT demonstrated good sensitivity for specimens with high viral loads and satisfactory specificity for low-risk, asymptomatic healthcare workers.

EURAMOS-1, an international randomised study for osteosarcoma: results from pre-randomisation treatment.

BACKGROUND: Four international study groups undertook a large study in resectable osteosarcoma, which included two randomised controlled trials, to determine the effect on survival of changing post-operative chemotherapy based on histological response. PATIENTS AND METHODS: Patients with resectable osteosarcoma aged ≤40 years were treated with the MAP regimen, comprising pre-operatively of two 5-week cycles of cisplatin 120 mg/m(2), doxorubicin 75 mg/m(2), methotrexate 12 g/m(2) × 2 (MAP) and post-operatively two further cycles of MAP and two cycles of just MA. Patients were randomised after surgery. Those with ≥10% viable tumour in the resected specimen received MAP or MAP with ifosfamide and etoposide. Those with <10% viable tumour were allocated to MAP or MAP followed by pegylated interferon. Longitudinal evaluation of quality of life was undertaken. RESULTS: Recruitment was completed to the largest osteosarcoma study to date in 75 months. Commencing March 2005, 2260 patients were registered from 326 centres across 17 countries. About 1334 of 2260 registered patients (59%) were randomised. Pre-operative chemotherapy was completed according to protocol in 94%. Grade 3-4 neutropenia affected 83% of cycles and 59% were complicated by infection. There were three (0.13%) deaths related to pre-operative chemotherapy. At definitive surgery, 50% of patients had at least 90% necrosis in the resected specimen. CONCLUSIONS: New models of collaboration are required to successfully conduct trials to improve outcomes of patients with rare cancers; EURAMOS-1 demonstrates achievability. Considerable regulatory, financial and operational challenges must be overcome to develop similar studies in the future. The trial is registered as NCT00134030 and ISRCTN 67613327.

Interfragmentary compression profile of 4 headless bone screws: an analysis of the compression lost on reinsertion.

PURPOSE: To evaluate the interfragmentary compression force generated by 4 different types of headless compression screws and to examine the effects of removal and reinsertion of the screw. METHODS: We chose foot bones rather than scaphoids for the model because they were larger and would enable comparison of 2 screw designs in the same bone, thereby controlling for the effect of interspecimen variability. A transverse osteotomy was made in 10 fresh-frozen cadaveric navicular bones and 10 medial cuneiforms. A load cell was used to measure compression between the 2 fragments as a screw was inserted across the fracture. Each bone was tested twice, with an Acutrak Mini (Acumed, Hillsboro, OR; n = 10) and an SBi AutoFIX screw (SBi, Morrisville, PA; n = 10) or an Extremifix (Osteomed, Addison, TX; n = 10) and a Barouk screw (Depuy, Warsaw, IN; n = 10). Compression was recorded at initial insertion and on removal and reinsertion of the screw twice to the same position. Compression was also measured after one additional full turn further than the initial position. RESULTS: The mean interfragmentary compression generated by the Acutrak Mini screw was greater than that of the SBi AutoFIX screw (96 N vs 22 N). There was a trend toward a greater mean compression generated by the Extremifix screw compared to the Barouk screw (85 N vs 22 N). There was a significant loss of compression upon removal and reinsertion of the screws. An additional full turn of the screw was able to re-establish a large proportion of the original compression. CONCLUSIONS: The compression forces achieved by headless screw systems appeared to vary according to the screw design, depth of insertion, and the quality of the bone. Substantial compression was lost if the screw was removed and replaced. Some screw designs appeared to require a greater depth of insertion to achieve effective compression, and the number of additional turns required to re-establish compression might vary according to the thread design. CLINICAL RELEVANCE: Surgeons should be aware of the compression profile of each screw design and the effect of screw removal and reinsertion in the clinical setting of small bone fixation.

Development of monoclonal antibody-based galactomannoprotein antigen-capture ELISAs to detect Aspergillus fumigatus infection in the invasive aspergillosis rabbit models.

Aspergillus fumigatus is one of the most prominent opportunistic fungal pathogens in immunocompromised hosts. Early recognition of this infection along with prompt antifungal therapy may increase the survival rate. We expressed two potential bio-markers of A. fumigatus infection-galactomannoprotein Afmp1p and Afmp4p in Pichia pastoris. We generated 33 monoclonal antibodies (MAbs), 20 against recombinant Afmp1p (rAfmp1p) and the other 13 against recombinant Afmp4p (rAfmp4p). Subsequently, we developed two antigen-capture enzyme-linked immunosorbent assays (ELISAs) which employed MAbs as both the capture and the detection antibodies for rAfmp1p and rAfmp4p. The two antigen-capture ELISAs specifically detected Afmp1p/Afmp4p in cultures of A. fumigatus and had no cross-reaction with other tested pathogenic fungi, including Penicillium marneffei and other pathogenic Aspergillus species. The Afmp1p-captured ELISA would be positive even when the culture supernatant of A. fumigatus had been diluted to 128-fold of its original concentration. The two antigen ELISAs could capture circulating or excreted antigens during the acute phase of invasive aspergillosis (IA) in the animal model, and had no cross-reactivity to other Aspergillus-challenged animal models. We developed two antigen-capture ELISAs for the laboratory diagnosis of A. fumigatus infection. These two antigen-capture ELISAs may be useful in the clinical diagnosis of aspergillosis.

Primary percutaneous coronary intervention for ST elevation myocardial infarction: performance with focus on timeliness of treatment.

OBJECTIVE: To review primary percutaneous coronary interventions performed for patients with ST elevation myocardial infarction with a focus on door-to-treatment time, especially after introduction of a new management programme in November 2003. DESIGN: Retrospective study. SETTING: Regional hospital, Hong Kong. PATIENTS: All patients with ST elevation myocardial infarction who underwent primary percutaneous coronary intervention in our hospital from January 2002 to December 2007. RESULTS: In all, 209 patients with ST elevation myocardial infarction had primary percutaneous coronary interventions between January 2002 and December 2007; 140 of them were admitted within office hours, 125 of whom came directly from Accident and Emergency Department. The mean door-to-balloon time of these patients was 115 minutes, and in 41% the time was less than 90 minutes (as recommended by the American College of Cardiology/American Heart Association guidelines). Since introduction of the new programme, the mean door-to-balloon time has diminished significantly, from 146 to 116 minutes (P=0.047). Delay in diagnosis (28%) and Cardiac Catheterization Laboratory being occupied (20%) were the two most common reasons for prolonged door-to-balloon times. CONCLUSION: We achieved satisfactory performance in our primary percutaneous coronary intervention programme, providing timely reperfusion therapy for patients with ST elevation myocardial infarction. A well-organised and systematic clinical pathway is a prerequisite for a centre that provides a timely and effective primary percutaneous coronary intervention service for patients with ST elevation myocardial infarction. Better public education and greater awareness on the part of medical service providers are needed, so as to facilitate urgent revascularisation and improve outcomes in patients with ST elevation myocardial infarction.

Differential expression of survivin splice isoforms in medulloblastomas.

Survivin, a member of the inhibitor of apoptosis protein family, is implicated in the dysregulation of apoptosis in human cancers. Survivin and survivin-deltaEx3, one of its two alternatively spliced isoforms, confer anti-apoptotic activities in human tumours, while survivin-2B antagonizes such anti-apoptotic properties. The current study was undertaken to examine the mRNA expression of survivin isoforms and their correlation with clinical staging and outcome in 20 medulloblastoma (MB) tumours, three MB cell lines and normal brain tissues (a foetal and an adult cerebellum) by densitometry scanning of 32p-dCTP incorporated reverse transcription polymerase chain reaction (RT-PCR) products and quantitative real-time PCR. Our results showed that the normal adult brain only expressed low levels of survivin-deltaEx3 mRNA, while the foetal brain expressed all three isoforms, with wild-type survivin as the dominant transcript. All three survivin isoforms were detected in all the MB cell lines and tumours analysed. Immunohistochemical staining also demonstrated survivin protein expressions in all five paraffin-embedded MBs, with predominant nuclear localization. Although overexpressions of survivin were not associated with the presence of metastatic MB or tumour histological subtypes, elevated expressions of survivin-deltaEx3 were significantly associated with progressive/recurrent tumours (P-value = 0.024). Our data demonstrated that overexpression of survivin mRNA is a common feature in MBs, may contribute to their anti-apoptosis properties and clinical behaviours, and predicts a poor clinical outcome, independent of clinical staging or tumour histology.

Triage rapid initial assessment by doctor (TRIAD) improves waiting time and processing time of the emergency department.

AIM: To evaluate the effect of triage rapid initial assessment by doctor (TRIAD) on waiting time and processing time of an emergency department (ED) without extra staff. METHOD: A senior emergency doctor was put into triage instead of a consultation cubicle for seven shifts of 9 hours each. All the patients were assessed and necessary interventions started at the time of triage. Waiting time and processing time of various categories of patients were compared with a control group that was sampled during the week before the trial period. RESULTS: In total, there were 1310 cases in the trial period and 1355 controls. Over a quarter (27%) of the patients received triage doctor interventions. The average waiting time was reduced by 38% and the average processing time by 23%. Patients without triage intervention also had a 24% shorter waiting time because of overall improvement in efficiency. Trauma patients and patients needing radiography particularly benefited from the new system. The waiting time and processing time of category 4 and 5 patients improved significantly as a result of more efficient processing of more urgent cases. CONCLUSION: The waiting time and processing time of the ED were greatly reduced by TRIAD without extra manpower.

Midazolam is more likely to cause hypotension than etomidate in emergency department rapid sequence intubation.

OBJECTIVE: To compare the haemodynamic effect of low dose midazolam and etomidate as induction agent in emergency department rapid sequence intubation. METHODS: A prospective observational study in two phases. In phase one, midazolam 2-4 mg was used as induction agent and in phase two, etomidate 0.2-0.3 mg/kg was used. The haemodynamic data were recorded before and after intubation for comparison. Changes in mean systolic blood pressure were analysed with SPSS software. RESULTS: A 10% decrease in mean systolic blood pressure was observed in the midazolam group (p = 0.001) while there was no significant change in the etomidate group. Some 19.5% of patients had hypotension after being given midazolam while only 3.6% with etomidate (p = 0.002). Patients older than 70 tended to have more hypotension episodes but the difference was not statistically significant. CONCLUSIONS: Midazolam, even in low dose, was more likely than etomidate to cause significant hypotension when used as an induction agent for rapid sequence intubation. Etomidate is a better alternative.

A survey on the involvement of accident and emergency doctors in medicolegal work in Hong Kong.

This study reports the results from a questionnaire survey on the pattern of medico-legal work undertaken by doctors working in Accident & Emergency Departments (ED) and their self-evaluation of competency in forensic medicine. A total of 155 questionnaires were returned with a response rate of 46%. Only 30% (46) respondents were fellows of the Hong Kong College of Emergency Medicine but 46% (71) had more than 6 years of experience working in the ED. Most of the requests for medical report came from police and insurance companies. Fellows had more experience writing reports on homicide, sexual assault and child abuse than non-fellows did. Nearly all fellows and three quarters (74%) of non-fellows had given evidence in courts of law. Physical assault was the commonest and sexual assault the least common experience. Most respondents had experience of attending district court (83%), followed by coroner inquest (67%), magistracy (66%) and high court (45%). Respondents were asked to rate themselves on their competence in various subject areas. It can be seen that respondents were less comfortable in areas like homicide, child abuse and sexual assault. On the job coaching by a senior seems to be the major mode of training. Both fellows (61%) and non-fellows (36%) favored some form of courses with a hands-on workshop element in future.

The utility of spectral karyotyping in the cytogenetic analysis of newly diagnosed pediatric acute lymphoblastic leukemia.

We applied multicolor spectral karyotyping (SKY) to a panel of 29 newly diagnosed pediatric pre B-cell ALLs with normal and abnormal G-banded karyotypes to identify cryptic translocations and define complex chromosomal rearrangements. By this method, it was possible to define all add chromosomes in six cases, a cryptic t(12;21)(p13;q11) translocation in six cases, marker chromosomes in two cases and refine the misidentified aberrations by G-banding in two cases. In addition, we identified five novel non-recurrent translocations - t(2;9)(p11.2;p13), t(2;22) (p11.2;q11.2), t(6;8)(p12;p11), t(12;14)(p13;q32) and t(X;8)(p22.3;q?). Of these translocations, t(2;9), t(2;22) and t(12;14) were identified by G-banding analysis and confirmed by SKY. We characterized a t(12;14)( p13;q32) translocation by FISH, and identified a fusion of TEL with IGH for the first time in ALL. We identified a rearrangement of PAX5 locus in a case with t(2;9)(p11.2;p13) by FISH and defined the breakpoint telomeric to PAX5 in der(9)t(3;9)(?;p13). These studies demonstrate the utility of using SKY in combination with G-banding and FISH to augment the precision with which chromosomal aberrations may be identified in tumor cells.

Attitude towards rape among doctors working in the emergency department.

In this study, a 29-item questionnaire survey was conducted to explore the attitude and knowledge toward rape amongst doctors working in Hong Kong. The Likert scale was used for questions on attitude and knowledge. A composite score was computed for both attitude and knowledge. Comparisons of the attitude and knowledge scores were made between doctors of different genders and ranks. Existing practices in the handling of rape cases were also explored. The response rate was 58%; 175 questionnaires were completed by 147 (84%) male and 28 (16%) female doctors. There were 12 (6.3%) consultants, 44 (23%) senior medical officers and 119 (62%) medical officers. The average length of emergency department experience was 4.7 years. Most doctors held a favourable attitude towards rape victims, and there was no significant difference between senior and junior doctors (P=0.062) or between doctors of different genders (P=0.793). However, 36% of the doctors agreed that 'a women should be responsible for preventing her own rape', and more female doctors agreed that 'a woman can successfully resist rape if she tries hard enough' (P<0.042). Senior doctors had a higher knowledge score (P<0.0001). The correlation between knowledge and attitude scores was low (Spearman coefficient 0.258; P<0.05). In conclusion, doctors working in the emergency department generally held favourable attitudes towards rape victims. However, there is still room for improvements in attitude and knowledge. A one-stop service is suggested to avoid fragmentation and prevent 'revictimization'.

Profile and outcomes of patients transported to an accident and emergency department by helicopter: prospective case series.

OBJECTIVES: To study the profile of airlifted patients and their outcomes after arrival at the hospital, and to evaluate the appropriateness of their prehospital care and the decision to use aeromedical evacuation. DESIGN: Prospective case series. SETTING: Accident and emergency department of a public hospital, Hong Kong. PATIENTS: All patients transported to the department by a helicopter of the Government Flying Service from June 1998 through November 1998. MAIN OUTCOME MEASURES: Demographic data, sources and locations of referral, clinical features, triage category, interventions used, and outcome. RESULTS: A total of 186 patients were transferred by helicopter during the 6-month study period. The 101 patients who had been transferred from a rural hospital or clinic were older (mean age, 50 years versus 35 years), comprised more females (55% versus 26%), had a higher overall mortality rate (19.8% versus 3.6%), and had a higher hospital admission rate (91.1% versus 37.6%) than the 85 patients who had been airlifted from the scene of an emergency. Neurological disorders were the most common presentation among interfacility transfers (21.8%). Among the 85 scene transfers, limb injuries (32.1%) and heat illnesses (24.4%) were the most common reasons for helicopter transport. Most interfacility transfers were appropriate, but 34.1% of patients who had been transferred from the scene of the emergency were later discharged and 21.1% refused consultation. CONCLUSIONS: Scene and interfacility transfers by helicopter have different patient profiles, and a substantial proportion of scene transfers may be inappropriate. Guidelines such as field triage and helicopter dispatch criteria need to be established.

Home accidents in elderly patients presenting to an emergency department.

A prospective study was carried out in an Accident and Emergency department (A&E) to (1) examine the pattern of home accidents in elderly patients presenting to the A&E; (2) determine the nature and mechanisms of the accidents; and (3) investigate the associated factors in these accidents. All patients aged 65 or above with a history of injury at home within one week were included. Patients who needed immediate resuscitation and patients with mental illness or violent behaviour were excluded. A convenient sample was chosen during an 8-week period. A standardized questionnaire was used to collect data on (1) demographics; (2) nature of the accident and injury; and (3) health status. Health status assessment involved three components: physical status, drug history and past health. A total of 100 subjects were included giving an average occurrence of 3.3 cases per shift. The mean age of the group was 75 with female patients (66) outnumbering the males by about two to one. The toilet was the most common site (29%) of home accident, followed by the sitting room (18%), the kitchen (14%), the bedroom (11%) and the dining room (10%). In 79 cases the patient was alone at home during the accident. Falls were the most common (75%) type of accident. The remaining 25% of injuries were categorized as sharps injury (8%), foreign body ingestion (6%), crush injury (4%), burns/scald (3%), hit by/onto fallen objects (3%) and finally, electric shock (1%). Eighteen fractures were recorded. Thirty-two patients were admitted, 16 to the surgical ward and 16 to the orthopedic ward. In the functional assessment only 34 patients could perform the get-up-and-go test satisfactorily and only 61 patients had good hand grasp. Visual and hearing impairment were common. Over 45% of the patients had more than one disease and the majority of patients (80) were taking some medication. The roles of A&E staff in the prevention of home accidents in the elderly are discussed.

Candidates for thrombolytic treatment in acute ischaemic stroke--where are our patients in Hong Kong?

OBJECTIVE: Tissue plasminogen activator (t-PA) has been approved by the Food and Drug Administration in the treatment of patients with acute ischaemic stroke presenting within three hours from onset of symptoms. This study aims to identify the potential number of stroke patients suitable for t-PA in Hong Kong. METHODS: All patients with a clinical diagnosis of acute stroke were recruited. Data collected included demographics, vital signs, medical history, contraindications to thrombolysis, severity of stroke (Canadian neurological scale), time course from onset of symptoms to computed tomography, computed tomography results, and final diagnoses by physicians. RESULTS: During the five month study period, 201 patients were recruited and nine were subsequently excluded from further analysis because computed tomography was not performed. Their mean age was 70.9 (range from 41-91) years. Eighty (41.7%) and 100 (52.1%) patients presented to our emergency department within two hours and three hours respectively from symptom onset. The mean severity score (Canadian neurological scale) was 7.83 (out of a maximum of 11.5). A total of 132 (68.8%) patients had acute ischaemic stroke confirmed by computed tomography. Mean delay in computed tomography was 4.91 hours. Fourteen (7.3%) and 52 (27.1%) of all patients had computed tomography of the brain done within one and two hours respectively. Only 20 patients (10.45%) could meet the three hour criteria as stated in the National Institute of Neurologic Disorders and Stroke rt-PA stroke study and seven (3.6%) of them were confirmed to have acute ischaemic stroke. Two patients were further excluded because of high systolic blood pressure and current warfarin medication. CONCLUSION: At present very few patients could benefit from thrombolytic treatment. Delays in the chain of recovery in stroke management should be identified and corrected.