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S K Lau

Publications and source records attributed to S K Lau.

At least 19 recordsLinked to original sources
PubMed2004

Toxic scarlet fever complicating cellulitis: early clinical diagnosis is crucial to prevent a fatal outcome.

We describe a case of toxic scarlet fever in a healthy adult with streptococcal cellulitis of the right elbow as a result of skin abrasion. The clinical picture mimicked that of drug eruption after treatment of cellulitis with antibiotics. Among the five cases of scarlet fever complicating cellulitis, including the present one, reported in the English literature, four had severe systemic complications and two died. As a result of re-emergence of invasive streptococcal infections, clinicians should be aware of the differential diagnosis of scarlet fever in patients presenting with cellulitis and skin rash. Early clinical diagnosis is crucial to exclude drug eruptions, prompt initiation of antibiotic treatment, and prevention of the potentially fatal outcome.

Adult↗
PubMed2001

Use of continuous passive motion after total knee arthroplasty.

Sixty primary total knee arthroplasties in 43 Chinese patients were included into a prospective study. Twenty-six patients who had unilateral knee arthroplasty were randomized to receive continuous passive motion (CPM) or immobilization in the first week. The 2 groups of patients were comparable in demographic data and preoperative knee range of motion (ROM). In 17 patients who had 1-stage sequential bilateral arthroplasties, one side had CPM and the other side was immobilized. The active knee ROM was assessed regularly until 1 year after the operation. For all patients, the early active knee ROM in the CPM group was significantly better than the immobilization group. There was no difference after 7 days, however. For patients who had 1-stage bilateral total knee arthroplasties, the active knee ROM was significantly better on the CPM side until day 28. After 4 weeks, there was no difference between the CPM group and the immobilization group. Immobilization after total knee arthroplasty does not preclude good ROM.

Adult↗
PubMed2001

Laribacter hongkongensis gen. nov., sp. nov., a novel gram-negative bacterium isolated from a cirrhotic patient with bacteremia and empyema.

A bacterium was isolated from the blood and empyema of a cirrhotic patient. The cells were facultatively anaerobic, nonsporulating, gram-negative, seagull shaped or spiral rods. The bacterium grows on sheep blood agar as nonhemolytic, gray colonies 1 mm in diameter after 24 h of incubation at 37 degrees C in ambient air. Growth also occurs on MacConkey agar and at 25 and 42 degrees C but not at 4, 44, and 50 degrees C. The bacterium can grow in 1 or 2% but not 3, 4, or 5% NaCl. No enhancement of growth is observed with 5% CO(2). The organism is aflagellated and nonmotile at both 25 and 37 degrees C. It is oxidase, catalase, urease, and arginine dihydrolase positive, and it reduces nitrate. It does not ferment, oxidize, or assimilate any sugar tested. 16S rRNA gene sequencing showed that there are 91 base differences (6.2%), 112 base differences (7.7%), and 116 base differences (8.2%) between the bacterium and Microvirgula aerodenitrificans, Vogesella indigofera, and Chromobacterium species, respectively. The G+C content (mean and standard deviation) is 68.0% +/- 2.43%, and the genomic size is about 3 Mb. Based on phylogenetic affiliation, the bacterium belongs to the Neisseriaceae family of the beta-subclass of Proteobacteria. For these reasons, a new genus and species, Laribacter hongkongensis gen. nov., sp. nov., is proposed, for which HKU1 is the type strain. Further studies should be performed to ascertain the potential of this bacterium to become an emerging pathogen.

Bacteremia↗
PubMed2001

Group G beta-hemolytic streptococcal bacteremia characterized by 16S ribosomal RNA gene sequencing.

Little is known about the relative importance of the four species of Lancefield group G beta-hemolytic streptococci in causing bacteremia and the factors that determine the outcome for patients with group G beta-hemolytic streptococcal bacteremia. From 1997 to 2000, 75 group G beta-hemolytic streptococcal strains were isolated from the blood cultures of 66 patients. Sequencing of the 16S rRNA genes of the group G beta-hemolytic streptococci showed that all 75 isolates were Streptococcus dysgalactiae subspecies equisimilis. The API system (20 STREP) and Vitek system (GPI) successfully identified 65 (98.5%) and 62 (93.9%) isolates, respectively, as S. dysgalactiae subspecies equisimilis with >95% confidence, whereas the ATB Expression system (ID32 STREP) only successfully identified 49 isolates (74.2%) as S. dysgalactiae subspecies equisimilis with >95% confidence. The median age of the patients was 76 years (range, 33 to 99 years). Fifty-six patients (85%) were over 60 years old. All patients had underlying diseases. No source of the bacteremia was identified (primary bacteremia) in 34 patients (52%), whereas 17 (26%) had cellulitis and 8 (12%) had bed sore or wound infections. Fifty-eight patients (88%) had community-acquired group G streptococcal bacteremia. Sixty-two patients (94%) had group G Streptococcus recovered in one blood culture, whereas 4 patients (6%) had it recovered in multiple blood cultures. Fifty-nine patients (89%) had group G Streptococcus as the only bacterium recovered in their blood cultures, whereas in 7 patients other bacteria were recovered concomitantly with the group G Streptococcus in the blood cultures (Staphylococcus aureus in 3, Clostridium perfringens in 2, Citrobacter freundii in 1, and Bacteroides fragilis in 1). Overall, 10 patients (15%) died. Male sex, diagnosis other than cellulitis, hospital-acquired bacteremia, and multiple positive blood cultures were associated with mortality [P < 0.005 (relative risk [RR] = 7.6), P < 0.05 (RR = 3.7), P < 0.005 (RR = 5.6), and P < 0.05 (RR = 5.6), respectively]. Unlike group C beta-hemolytic streptococcal bacteremia, group G beta-hemolytic streptococcal bacteremia is not a zoonotic infection in Hong Kong.

Adult↗
PubMed2000

Wound dressing with sustained anti-microbial capability.

To overcome current limitations in wound dressings for treating mustard-burn induced septic wound injuries, a nonadherent wound dressing with sustained anti-microbial capability has been developed. The wound dressing consists of two layers: the upper layer is a carboxymethyl-chitin hydrogel material, while the lower layer is an anti-microbial impregnated biomaterial. The hydrogel layer acts as a mechanical and microbial barrier, and is capable of absorbing wound exudate. In physiological fluid, the carboxymethylated-chitin hydrogel swells considerably, imbibing up to 4 times its own weight of water and is also highly porous to water vapor. The moisture permeability of the dressing prevents the accumulation of fluid in heavily exudating wounds seen in second-degree burns. The lower layer, fabricated from chitosan acetate foam, is impregnated with chlorhexidine gluconate. From the in vitro release studies, the loading concentration was optimized to deliver sufficient anti-microbial drug into the wound area to sustain the anti-microbial activity for 24 h. The anti-microbial activity of the dressing against Pseudomonas aeruginosa and Staphylococcus aureus was tested using the Bauer-Kirby Disk Diffusion Test.

Anti-Infective Agents↗
PubMed2000

Imaging of non-small-cell lung cancer with indium-111 pentetreotide.

PURPOSE: Lung cancer is the leading cause of cancer deaths in the United States. Non-small-cell lung cancer (NSCLC) accounts for 75% to 85% of lung cancers. CT has been the standard anatomic study for localizing and staging NSCLC, although it is associated only with moderate accuracy. In-111 pentetreotide, a radiolabeled somatostatin analog largely used in the scintigraphic localization of neuroendocrine tumors, has been shown incidentally to identify NSCLC lesions. This observation is important in the workup for metastatic disease for neuroendocrine tumors, because presumed metastatic lesions may actually be second primary tumors of NSCLC. In-111 may also serve as a potentially useful adjunct to CT in the anatomic evaluation of NSCLC. The purpose of this study was to determine the likelihood of detecting and localizing NSCLC using In-111 pentetreotide scintigraphy. MATERIALS AND METHODS: Ten patients with known or possible NSCLC were examined using In-111 pentetreotide. Scans were compared with the patients' previously performed chest radiographs and CT scans. RESULTS: In-111 pentetreotide imaging correctly identified sites of tumor involvement as detected by chest CT and surgery in all 10 patients with NSCLC. CONCLUSION: This study demonstrates the uptake of In-111 pentetreotide by NSCLC. This important observation should be considered in the workup for metastatic disease of neuroendocrine tumors with In-111 pentetreotide, because NSCLC can be a source of false-positive findings. In-111 pentetreotide imaging may also serve as a potentially useful adjunct to CT for identifying obscured or equivocal lesions and as an aid in localizing tissue for biopsy.

Aged↗
PubMed1998

Ameloblastic carcinoma of the jaws. A report of two cases.

Two cases of ameloblastic carcinoma of the jaws are reported. Histopathologically, the lesions showed cytologic features of malignancy in addition to classical ameloblastoma patterns and were therefore documented as examples of ameloblastic carcinoma. The negative cytokeratin expression by the malignant cells on histochemical analysis is notably different from that normally observed in classical ameloblastomas.

Adult↗
PubMed1997

Prospective randomized study of thrice weekly six-month and nine-month chemotherapy for cervical tuberculous lymphadenopathy.

The aim of this study is to compare the efficacy of a thrice weekly 6-month regimen, 4S3H3R3Z3/2H3R3 (which consists of an initial 4 months of streptomycin (S), isoniazid (H), rifampicin (R), and pyrazinamide (Z) followed by 2 months of isoniazid and rifampicin), with a thrice weekly 9-month regimen, 4S3H3R3Z3/5H3R3 (which consists of an initial 4 months of streptomycin, isoniazid, rifampicin, and pyrazinamide followed by 5 months of isoniazid and rifampicin), in the treatment of cervical tuberculous lymphadenopathy. A total of 113 patients were recruited between August 1987 and December 1993. Twenty-two patients were excluded from the analysis because of defaulting treatment or modification of regimen. Ninety-one patients were included in the analysis. Forty-three patients were given the 6-month regimen, and 48 patients were given the 9-month regimen. Two (5%) patients of the 6-month regimen and one (2%) patient of the 9-month regimen had primary failure after completion of treatment (relative risk, 2.23; 95% confidence interval, 0.21 to 23.76). Of the 88 patients who had initial clinical remission after completion of treatment, the 5-year actuarial remission rates were 89% for the 6-month regimen and 90% for the 9-month regimen (Wilcoxon, p = 0.44). There were no significant differences of both primary failure rate and 5-year actuarial remission rate of the two regimens. The 6-month regimen is recommended as the initial treatment of tuberculous lymphadenopathy.

Administration, Oral↗
PubMed1994

Cord compression due to extramedullary hemopoiesis in a patient with thalassemia.

STUDY DESIGN: This is a case report of a patient with thalassemia who had acute spinal cord compression at the T3 to T8 level and presented for treatment. METHODS: Magnetic resonance imaging and surgical decompression and transfusion therapy was chosen as the preferred treatment modality. RESULTS: Neurologic recovery was satisfactory from the immediate postoperative period, and full recovery was observed 2 months after surgery. CONCLUSION: Clinical awareness is important for early diagnosis. Documentation with an imaging technique, such as magnetic resonance imaging, is mandatory. Optimal treatment is tailor-made and depends on the clinical situation and the expertise available.

Adult↗
PubMed1994

Ofloxacin eardrop treatment for active chronic suppurative otitis media: prospective randomized study.

This report presents a prospective randomized study of 0.3 percent ofloxacin eardrops for the treatment of active chronic suppurative otitis media. Twenty-nine patients were treated with ofloxacin eardrops for 1 week, and another 27 patients were treated with Augmentin for 1 week. One week after completion of treatment, 22 (76%) patients of the group treated with ofloxacin had dry ears, and only seven (26%) patients treated with Augmentin had dry ears. Ofloxacin eardrops were effective in the initial treatment of active chronic suppurative otitis media.

Administration, Oral↗
PubMed1993

Relationship between intrahepatic expression of hepatitis B viral antigens and histology in Chinese patients with chronic hepatitis B virus infection.

Hepatic cellular and subcellular expression of hepatitis B virus (HBV) antigens--HBsAg, HBcAg, and HBeAg--in 143 Chinese patients with chronic HBV infection were studied by immunohistochemical techniques. Nuclear expression of HBcAg and nuclear and cytoplasmic expression of HBeAg showed a secular trend decreasing from the carrier state and chronic persistent hepatitis (CPH), through chronic active hepatitis (CAH), to cirrhosis with or without hepatocellular carcinoma. In contrast, cytoplasmic HBcAg expression was significantly greater in patients with CPH and CAH (P < .0108). In addition, cytoplasmic HBcAg correlated significantly with lobular activity, portal inflammation, and hepatitic activity (P < or = .007). Expression of cytoplasmic HBcAg also exceeded cytoplasmic HBeAg and nuclear HBcAg in liver specimens showing significant damage (P < .038). HBsAg, however, showed no secular trend and was not related to liver histology. The authors' findings support the theory that HBcAg is also the viral target antigen for immune-mediated liver damage in Chinese patients with chronic HBV infection.

Adolescent↗
PubMed1993

Plastic adhesive drapes and wound infection after hip fracture surgery.

One hundred and twenty patients with acute hip fractures treated operatively were randomized into two groups. In the 'drape' group (n = 65) the operation site was covered with plastic adhesive drape after preparation. In the 'no drape' group (n = 55) the operation site was left uncovered. The two groups were otherwise matched. Swabs for culture were taken from skin adjacent to the wound before closure. The drape group had four positive wound swabs. There was only one positive wound swab for the no-drape group. There was no difference in the post-operative wound infection rates.

Adhesiveness↗
PubMed1993

The use of double latex gloves during hip fracture operations.

A prospective study was undertaken to determine the perforation rate of surgical gloves when double-gloving techniques were employed in 120 hip fracture operations. One or more perforations occurred in 30 operations (25%). In 10 operations (8.3%), perforations of both the outer and inner gloves occurred at corresponding sites. The surgeons were able to recognize the perforations during the surgery on five occasions only. Of the 64 perforations identified, 41 (64%) occurred in the left (nondominant) hands, and 42 (65.6%) occurred at the tips of thumbs and index fingers. Nearly half of the perforations (46.9%) occurred at the thumb and index finger of left (nondominant) hands. To reduce the perforation rate, further protection of the thumb and index finger of the nondominant hand of surgeons is therefore required.

Accidents, Occupational↗
PubMed1993

Apparent apical endolymphatic hydrops: computer-aided three-dimensional reconstruction and histologic study of the apical turn of the cochlear duct.

Computer-aided three-dimensional reconstruction of the apex of a cochlea and microscopic evaluation of 14 clinically and histologically normal temporal bones were used to demonstrate that what appears to be distention of Reissner's membrane is normal anatomy. The apparent distention is the transition area between the circular insertion of the apex of the cochlear duct and the rest of Reissner's membrane, which is straight.

Adult↗
PubMed1992

Serous otitis media. An opportunity for early recognition of nasopharyngeal carcinoma.

In a prospective study of 271 new patients with nasopharyngeal carcinoma, 36 (13.3%) were found to have cranial nerve involvement. Serous otitis media (SOM) was found in 98 (41.4%) of 237 patients who had undergone complete otologic assessment. The local control of tumor and actuarial survival of three subgroups of patients, namely, 80 patients with SOM only, 11 patients with cranial nerve palsy only, and 18 patients with both SOM and cranial nerve palsy, were analyzed. The local control of tumor was better in patients with SOM alone than in those with cranial nerve palsy alone; those patients with both SOM and cranial nerve involvement had worse local control as well as survival. As SOM is not uncommon in the diagnosis of nasopharyngeal carcinoma, and adult-onset SOM is otherwise distinctly uncommon, this provides a good opportunity for early recognition and, perhaps, better control of nasopharyngeal carcinoma.

Actuarial Analysis↗
PubMed1992

Pathological basis of surgery in the management of postradiotherapy cervical metastasis in nasopharyngeal carcinoma.

Radical neck dissection was performed on 43 patients with nasopharyngeal carcinoma in whom persistent or recurrent cervical metastasis developed after radiotherapy. The pathologic nature of the tumor in the cervical lymph nodes was studied with step serial sectioning of the entire radical neck dissection specimen at 3-mm intervals. In 70% of patients, more tumor-harboring lymph nodes were detected in the specimen when compared with clinical examination. The extensive behavior of the tumor in the cervical metastases was reflected by the presence of extracapsular spread in 70% of the lymph nodes and the existence of isolated clusters of tumor cells in 35% of the specimens studied. Tumor tissue lying in close proximity to the spinal accessory nerve was demonstrated in 27.5% of the specimens, and 72% of the tumor-bearing lymph nodes were located in the posterior triangle. Radical neck dissection is recommended as the salvage procedure for these patients.

Adult↗
PubMed1992

Early changes of auditory brain stem evoked response after radiotherapy for nasopharyngeal carcinoma--a prospective study.

A prospective study of the effect of radiotherapy for nasopharyngeal carcinoma on hearing was carried out on 49 patients who had pure tone, impedance audiometry and auditory brain stem evoked response (ABR) recordings before, immediately, three, six and 12 months after radiotherapy. Fourteen patients complained of intermittent tinnitus after radiotherapy. We found that 11 initially normal ears of nine patients developed a middle ear effusion, three to six months after radiotherapy. There was mixed sensorineural and conductive hearing impairment after radiotherapy. Persistent impairment of ABR was detected immediately after completion of radiotherapy. The waves I-III and I-V interpeak latency intervals were significantly prolonged one year after radiotherapy. The study shows that radiotherapy for nasopharyngeal carcinoma impairs hearing by acting on the middle ear, the cochlea and the brain stem auditory pathway.

Adult↗