The safety of simultaneous bilateral total knee arthroplasty (TKA) remains controversial. The objective of the current study was to investigate perioperative morbidity and mortality rates within 30 days of simultaneous bilateral TKA. A detailed analysis of medical, surgical and anaesthesia records of 183 consecutive patients who underwent total knee arthroplasty between 2002 and 2006 was performed. The mean age of the patients was 67.6 years old. More than 80% had one or more co-morbidities, but none of them had ASA score greater than class 2. The mean hospital stay was 10 days, and the mean surgical time 156 minutes. Less than half of the patients (42.6%) required blood transfusion. The rate of perimorbidity was 15.3 % and there was no mortality in this series. We believe that simultaneous bilateral total knee arthroplasty is a safe and cost effective option for our patients, provided that patients are selected and informed appropriately.

Patients with breast cancer normally present with breastlump or abnormal mammogram. Dermatomyositis is rarelythe first presentation. We present a case of a 63-year-oldwoman who had generalised dermatitis, progressive fatigueand muscle weakness. She was first diagnosed asdermatomyositis and subsequently breast cancer. Her rashand muscle weakness progressed drastically over a month.Tumescent mastectomy and axillary surgery was performed,which led to gradual regression of her dermatomyositis oversix months. This case report emphasized in the benefit ofearly diagnosis and treatment of dermatomyositis andbreast cancer. Pros and cons of tumescent mastectomy isdiscussed as well.

INTRODUCTIONDengue (DEN) is a mosquito-borne viral disease which has become an increasing economic and health burden for the tropical and subtropical world. Plasma leakage is the most life threatening condition of DEN and may lead to hypovolaemic shock if not properly managed.

MATERIALS AND METHODSWe recently reported a unique dengue virus strain (D2Y98P) which upon intraperitoneal (IP) administration to immunocompromised mice led to systemic viral dissemination, intestine damage, liver dysfunction, and increased vascular permeability, hallmarks of severe DEN in patients (Tan et al, PLoS Negl Trop Dis 2010;4:e672).

RESULTSHere we report the clinical manifestations and features observed in mice subcutaneously (SC) infected with D2Y98P, which is a route of administration closer to natural infection. Similar to the IP route, increased vascular permeability, intestine damage, liver dysfunction, transient lymphopenia (but no thrombocytopenia) were observed in the SC infected mice. Furthermore, the SC route of infection was found more potent than the IP route whereby higher viral titers and earlier time-of-death rates were measured. In addition, various staining approaches revealed structurally intact blood vessels in the moribund animals despite pronounced systemic vascular leakage, as reported in dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS) patients. Interestingly, measurement of soluble mediators involved in vascular permeability indicated that vascular leakage may occur at an early stage of the disease, as proposed in DEN patients.

CONCLUSIONWe believe that this novel mouse model of DEN-associated vascular leakage will contribute to a better understanding of DEN pathogenesis and represents a relevant platform for testing novel therapeutic treatments and interventions.

Animals ; Capillary Permeability ; Dengue ; physiopathology ; Dengue Virus ; pathogenicity ; Disease Models, Animal ; Immunocompromised Host ; Mice ; Severe Dengue ; physiopathology

Objectives: To enhance the public awareness and facilitate diagnosis of osteoporosis, we aim to develop a new Chinese Osteoporosis Screening Algorithm (COSA) to identify people at high risk of osteoporosis. Methods: A total of 4747 postmenopausal women and men aged ! 50 from the Hong Kong Osteoporosis Study were randomly split into a development (N ¼ 2373) and an internal validation cohort (N ¼ 2374). An external validation cohort comprising 1876 community-dwelling subjects was used to evaluate the positive predictive value (PPV). Results: Among 11 predictors included, age, sex, weight, and history of fracture were significantly associated with osteoporosis after correction for multiple testing. Age- and sex-stratified models were developed due to the presence of significant sex and age interactions. The area under the curve of the COSA in the internal validation cohort was 0.761 (95% CI, 0.711e0.811), 0.822 (95% CI, 0.792e0.851), and 0.946 (95% CI, 0.908e0.984) for women aged < 65, women aged ! 65, and men, respectively. The COSA demonstrated improved reclassification performance when compared to Osteoporosis Self-Assessment Tool for Asians. In the external validation cohort, the PPV of COSA was 40.6%, 59.4%, and 19.4% forwomen aged < 65, women aged ! 65, and men, respectively. In addition, COSA > 0 was associated with an increased 10-year risk of hip fracture in women ! 65 (OR, 4.65; 95% CI, 2.24e9.65) and men (OR, 11.51; 95% CI, 4.16e31.81). Conclusions We have developed and validated a new osteoporosis screening algorithm, COSA, specific for Hong Kong Chinese.

BACKGROUND: We have noticed changes in paediatric anaphylaxis triggers locally in Singapore. OBJECTIVE: We aimed to describe the demographic characteristics, clinical features, causative agents and management of children presenting with anaphylaxis. METHODS: This is a retrospective study of Singaporean children presenting with anaphylaxis between January 2005 and December 2009 to a tertiary paediatric hospital. RESULTS: One hundred and eight cases of anaphylaxis in 98 children were included. Food was the commonest trigger (63%), followed by drugs (30%), whilst 7% were idiopathic. Peanut was the top food trigger (19%), followed by egg (12%), shellfish (10%) and bird's nest (10%). Ibuprofen was the commonest cause of drug induced anaphylaxis (50%), followed by paracetamol (15%) and other nonsteroidal anti-inflammatory drugs (NSAIDs, 12%). The median age of presentation for all anaphylaxis cases was 7.9 years old (interquartile range 3.6 to 10.8 years), but food triggers occurred significantly earlier compared to drugs (median 4.9 years vs. 10.5 years, p < 0.05). Mucocutaneous (91%) and respiratory features (88%) were the principal presenting symptoms. Drug anaphylaxis was more likely to result in hypotension compared to food anaphylaxis (21.9% vs. 2.7%, Fisher's exact probability < 0.01). There were 4 reported cases (3.6%) of biphasic reaction occurring within 24 h of anaphylaxis. CONCLUSION: Food anaphylaxis patterns have changed over time in our study cohort of Singaporean children. Peanuts allergy, almost absent a decade ago, is currently the top food trigger, whilst seafood and bird's nest continue to be an important cause of food anaphylaxis locally. NSAIDs and paracetamol hypersensitivity are unique causes of drug induced anaphylaxis locally.
Acetaminophen ; Anaphylaxis ; Anti-Inflammatory Agents, Non-Steroidal ; Arachis ; Child ; Cohort Studies ; Drug Hypersensitivity ; Food Hypersensitivity ; Humans ; Hypersensitivity ; Hypotension ; Ibuprofen ; Ovum ; Retrospective Studies ; Seafood ; Shellfish ; Singapore