Integrating images into the electronic patient record of the hospital authority of Hong Kong.

Over a period of 10 years the Hospital Authority has developed an integrated clinical information system (The Clinical Management System-CMS), including a territory-wide longitudinal electronic patient record (ePR). The CMS and ePR are used by over 4000 doctors and 20,000 other clinicians to document and review care. The ePR currently has nearly 3TB of data covering 44 million episodes for 6.4 million patients. To date the CMS has largely dealt with textual data. However, PACS technology is increasingly being adopted in the HA. This paper describes our strategy for taking the hospital image archives and making them available throughout the Authority as part of the longitudinal patient record, leveraging the ePR to distribute radiological and other images in a manner which is integrated, affordable and sustainable.

The Hong Kong Hospital Authority's information architecture.

Since 1994, the Hospital Authority has been developing and deploying clinical applications at its constituent 39 hospitals and clinics. The Clinical Management System (CMS) is now used by over 4000 doctors and 20000 other clinicians to document and review care. Since 1999, the territory-wide integrated Electronic Patient Record (ePR) has given clinicians a longitudinal view of the data collected through the CMS and its adjunct systems. The ePR currently has nearly 3TB of data covering 44 million episodes for 6.4 million patients. This paper describes the Hospital Authority's Information Architecture, which allows the ePR to accept and integrate any clinical information from any internal or external system. The ePR operates in a high volume and high performance environment, yet only requires low maintenance, while still retaining the information structure and semantics required for advanced applications.

A clinical prediction rule for diagnosing severe acute respiratory syndrome in the emergency department.

BACKGROUND: Accurate, objective models of triage for patients with suspected severe acute respiratory syndrome (SARS) could assess risks and improve decisions about isolation and inpatient treatment. OBJECTIVE: To develop and validate a clinical prediction rule for identifying patients with SARS in an emergency department setting. DESIGN: Retrospective analysis using a 2-step coefficient-based multivariable logistic regression scoring method with internal validation by bootstrapping. SETTING: 2 hospitals in Hong Kong. PARTICIPANTS: 1274 consecutive patients from 1 hospital and 1375 consecutive patients from another hospital. MEASUREMENTS: Points were assigned on the basis of history, physical examination, and simple investigations obtained at presentation. The outcome measure was a final diagnosis of SARS, as confirmed by World Health Organization laboratory criteria. RESULTS: Predictors for SARS on the basis of history (step 1) included previous contact with a patient with SARS and the presence of fever, myalgia, and malaise. Age 65 years and older and younger than 18 years and the presence of sputum, abdominal pain, sore throat, and rhinorrhea were inversely related to having SARS. In step 2, haziness or pneumonic consolidation on chest radiographs and low lymphocyte and platelet counts, in addition to a positive contact history and fever were associated with a higher probability of SARS. A high neutrophil count, the extremes of age, and sputum production were associated with a lower probability of SARS. In the derivation sample, the observed incidence of SARS was 4.4% for those assigned to the low-risk group (in steps 1 or 2); in the high-risk group, incidence of SARS was 21.0% for quartile 1, 39.5% for quartile 2, 61.2% for quartile 3, and 79.7% for quartile 4. This prediction rule achieved an optimism-corrected sensitivity of 0.90, a specificity of 0.62, and an area under the receiver-operating characteristic curve of 0.85. LIMITATIONS: The prediction rule may not apply to isolated cases occurring during an interepidemic period. Generalizability of the findings should be confirmed in other SARS-affected countries and should be prospectively validated if SARS returns. CONCLUSIONS: Our findings suggest that a simple model that uses clinical data at the time of presentation to an emergency department during an acute outbreak predicted the incidence of SARS and provided good diagnostic utility.

Epidemiological determinants of spread of causal agent of severe acute respiratory syndrome in Hong Kong.

BACKGROUND: Health authorities worldwide, especially in the Asia Pacific region, are seeking effective public-health interventions in the continuing epidemic of severe acute respiratory syndrome (SARS). We assessed the epidemiology of SARS in Hong Kong. METHODS: We included 1425 cases reported up to April 28, 2003. An integrated database was constructed from several sources containing information on epidemiological, demographic, and clinical variables. We estimated the key epidemiological distributions: infection to onset, onset to admission, admission to death, and admission to discharge. We measured associations between the estimated case fatality rate and patients' age and the time from onset to admission. FINDINGS: After the initial phase of exponential growth, the rate of confirmed cases fell to less than 20 per day by April 28. Public-health interventions included encouragement to report to hospital rapidly after the onset of clinical symptoms, contact tracing for confirmed and suspected cases, and quarantining, monitoring, and restricting the travel of contacts. The mean incubation period of the disease is estimated to be 6.4 days (95% CI 5.2-7.7). The mean time from onset of clinical symptoms to admission to hospital varied between 3 and 5 days, with longer times earlier in the epidemic. The estimated case fatality rate was 13.2% (9.8-16.8) for patients younger than 60 years and 43.3% (35.2-52.4) for patients aged 60 years or older assuming a parametric gamma distribution. A non-parametric method yielded estimates of 6.8% (4.0-9.6) and 55.0% (45.3-64.7), respectively. Case clusters have played an important part in the course of the epidemic. INTERPRETATION: Patients' age was strongly associated with outcome. The time between onset of symptoms and admission to hospital did not alter outcome, but shorter intervals will be important to the wider population by restricting the infectious period before patients are placed in quarantine.

Significance of squamous cells in fine needle aspiration cytology of the breast. A review of cases in a seven-year period.

OBJECTIVE: To delineate the significance of detecting squamous cells in fine needle aspiration biopsy of breast lesions. STUDY DESIGN: The authors reviewed 15 cases of fine needle aspiration cytology of the breast with a discernible number of squamous cells from the files of Pamela Youde Nethersole Eastern Hospital, Hong Kong, during a seven-year period from the start of 1994 to the end of 2001. The cytologic features were correlated with clinical, radiologic and histologic findings, if any. RESULTS: Among the 15 fine needle aspirates of the breast with a discernible number of squamous cells, 5 of them represented metaplastic carcinoma. The remaining consisted of 3 cases of fibroepithelial tumors, 1 case of duct ectasia, 3 cases of subareolar abscess, 2 cases of sclerosed intraduct papilloma and 1 case of benign breast cyst. In general, benign squamous cells were bland looking and often associated with anucleated squames. They were mitotically inactive and could show a good maturation pattern. Tumor cell cannibalism was rare. The presence of abundant, foamy macrophages in the background suggested a benign lesion. The primary diagnosis could be deduced by recognition of other features, such as the presence of myxoid stromal tissue and papillary structures. In contrast, malignant squamous cells in metaplastic carcinoma were more pleomorphic and mitotically active. Dyskeratosis and tumor cell cannibalism were obvious. Tumor diathesis and bizarre-shaped cells were sometimes found. CONCLUSION: Squamous cells occur in fine needle aspirates from a number of benign and malignant breast lesions. Benign conditions with abundant squamous cells may sometimes mimic malignant squamous lesions and vice versa. Careful assessment of the cytologic features of squamous cells and background appearance is crucial for achieving a correct diagnosis.

Fine needle aspiration cytology of ductal breast carcinoma with neuroendocrine differentiation. Review of eight cases with histologic correlation.

OBJECTIVE: To describe the fine needle aspiration cytology findings of ductal breast carcinoma with neuroendocrine differentiation and correlate them with the histologic appearance. STUDY DESIGN: We reviewed the cytologic features of eight cases of ductal carcinoma with neuroendocrine differentiation in the files of Pamela Youde Nethersole Eastern Hospital during the three-year period 1998-2000. Immunohistochemical study for neuroendocrine markers was performed, with ultrastructural correlation. RESULTS: All cases showed similar cytologic features. The smears were of moderate to high cellularity with predominantly dispersed or loosely cohesive tumor cells. The carcinoma cells were mostly of low cytologic grade. They possessed round and relatively uniform, eccentric nuclei; finely stippled chromatin; sometimes small, distinct nucleoli; and discrete cell borders. Abundant eosinophilic and focally granular cytoplasm was a common finding. In some of the cases there was accentuation of staining in the paranuclear region; it correlated with aggregates of dense core neurosecretory granules seen ultrastructurally. Mucoid substance was seen in the background in some of the aspirates. Histologic examination of the tumors showed invasive ductal carcinoma with an organoid growth pattern and sometimes mucinous component. The neuroendocrine differentiation was confirmed immunohistochemically. CONCLUSION: Although this subtype of ductal carcinoma probably carries no significant prognostic value per se, it has distinct cytologic features, rendering preoperative diagnosis possible. Recognition of this entity is important in order to avoid the misdiagnosis of neuroendocrine tumor metastatic to the breast.

Dirofilariasis of breast: report of two cases diagnosed by fine-needle aspiration biopsy.

We report on 2 cases of dirofilariasis of the breast occurring in adult Chinese females residing in Hong Kong. The diagnosis was made by fine-needle aspiration biopsies. The direct smears contained numerous acute inflammatory cells, including eosinophils. A partially necrotic adult nematode of about 400-450 microm in diameter was identified in the cell-block sections of each case. The worm was characterized by a thick cuticle with longitudinal cuticular ridges and fine transverse surface striations, abundant somatic muscle, an intestine, and a reproductive tube or uterus. The morphologic features of this round worm were most compatible with those of Dirofilaria repens. While the clinical and radiologic findings of dirofilariasis of the breast are nonspecific and mimic those of breast neoplasms or inflammatory conditions, a definitive diagnosis is possible with fine-needle aspiration biopsy. A correct diagnosis of dirofilariasis may help to spare patients from unnecessary medical and surgical interventions.