Search PubMed⌕ Search

Biomedical subjects

K K Tan

Publications and source records attributed to K K Tan.

At least 73 records · Page 4Linked to original sources

Haemorrhagic disease in newborn and older infants: a study in hospitalized children in Kelantan, Malaysia.

This is a retrospective study of the epidemiology, clinical features, laboratory findings, treatment and outcome of haemorrhagic disease in 42 Kelantanese infants who were admitted to Hospital Universiti Sains Malaysia during a 2-year period (1987-1988). Classical haemorrhagic disease of the newborn was the commonest presentation (48%), followed by early onset (29%) and late onset (24%) disease. Home deliveries accounted for 81% of the affected infants. Most of these babies were not given vitamin K at birth in contrast to those delivered in hospitals. All except one infant were breastfed. The six commonest presenting clinical features were pallor, jaundice, umbilical cord bleeding, tense fontanelle, convulsions and hepatomegaly. All the infants had prolonged prothrombin and partial thromboplastin times which were corrected by administration of vitamin K. Subdural haemorrhage was the commonest form of intracranial haemorrhage, followed by subarachnoid haemorrhage. The overall case fatality rate was 14%. The results of this study once again emphasize the value of vitamin K prophylaxis in the newborn.

Age Factors↗

Hemothorax due to hemorrhagic disease of the newborn.

A three day old male, term infant with hemothorax due to hemorrhagic disease of the newborn was treated successfully with vitamin K and thoracocentesis. Exclusive breast feeding and absence of vitamin K prophylaxis were important diagnostic clues, although hemothorax as a sole manifestation of hemorrhagic disease of the newborn is rare. This case highlighted the good prognosis of an uncommon complication when prompt diagnosis and appropriate treatment are instituted. The importance of vitamin K prophylaxis to all newborns is emphasized.

Drainage↗

Demonstration of the neurotransmitter role of calcitonin gene-related peptides (CGRP) by immunoblockade with anti-CGRP monoclonal antibodies.

1. Monoclonal antibodies (MAbs) against rat alpha-calcitonin gene-related peptide (alpha CGRP) were produced. Those which bound CGRP in a radioimmunoassay and inhibited the binding of 2-[125I]-iodohistidyl10-CGRP in a receptor binding assay were selected for immunoblockade experiments. 2. The effect of MAbs on CGRP inhibition of electrically stimulated contractions of the rat isolated vas deferens was characterized. Four out of 11 MAbs tested shifted the concentration-response curve of CGRP to the right compared with vehicle or irrelevant MAb control. MAb C4.19 produced equipotent blockade of rat alpha CGRP and rat beta CGRP and was chosen for further studies. MAb C4.19 had no pharmacologically significant effect on the concentration-response relationship of isoprenaline, rat beta-endorphin or somatostatin. 3. We demonstrated that the pharmacological response to CGRP in the presence of MAb C4.19 could be predicted when the dissociation constant and concentration of binding sites of the antibody were known. Comparison of experimental and computer simulated data showed good agreement for EC50 and maximum effect of CGRP in the presence of MAb C4.19. 4. Capsaicin at 1 microM inhibited the electrically stimulated contractions by 60.8% (95% confidence interval 51.8% to 69.9%). This effect was significantly attenuated by MAb C4.19 to 26.0% (95% confidence interval 15.2% to 36.8%; P < 0.003). 5. The immunoblockade of exogenous and endogenous CGRP described here, together with complementary evidence from other studies, strongly suggest that CGRP has a major neurotransmitter role at the neuroeffector junction of the rat vas deferens.

Animals↗

The optic nerve in the posterior ethmoid in Asians.

Anatomical dissections employing the endoscopic sphenoethmoidectomy technique were performed in 51 fresh Asian cadaveric heads. Specific data concerning the anatomical variations of the posterior ethmoid sinus and its relationships to the optic nerve were recorded. Approximately two-thirds (65%) of the specimens showed a direct relationship between the optic nerve and posterior ethmoid sinus. Posterior ethmoid cells with an optic canal bulge were found in 50.98% of the 102 sides dissected. In 14.7% no optic canal bulge was present, yet the optic nerve was intimately related to the posterior ethmoid sinus. In this latter group, the average thickness of bone separating the optic nerve from the posterior ethmoid sinus was 0.25 mm. The authors consider that in endoscopic sinus surgery, this type of relationship is potentially the most hazardous to the optic nerve.

Asian People↗

Non-O1 Vibrio cholerae septicaemia: a case report.

Non-O1 vibrio cholerae infections are associated with sporadic cases of gastroenteritis and extraintestinal infections. Septicaemia due to non-O1 vibrio cholerae is rare and are mainly reported in adults, particularly in immunocompromised patients. We report a case of non-O1 vibrio cholerae septicaemia and gastroenteritis in an 8-year-old child. The patient presented with bloody diarrhoea, fever and severe dehydration. Non-O1 vibrio cholerae were isolated from blood and stool cultures. The clinical course was uneventful after starting appropriate rehydration and supportive therapy.

Bacteremia↗

Lipoma of hypopharynx.

The histologically benign hypopharyngeal lipoma is a potentially fatal tumour because of the risk of upper airway obstruction. It may be asymptomatic or present with symptoms ranging from vague foreign-body sensation to sore throat, dysphagia or dysphonia. The diagnosis may be suggested by indirect or fibreoptic laryngoscopy. Lateral neck soft tissue X-ray and barium swallow may help but CT imaging of the pharynx enables a more precise preoperative diagnosis. Treatment is by surgical excision of the lesion either perorally, endoscopically or via a lateral pharyngotomy. Long-term follow-up is recommended due to the possibility of recurrence and metachronous lesions.

Adult↗

Omeprazole 40 mg o.m. combined with amoxycillin alone or with amoxycillin and metronidazole in the eradication of Helicobacter pylori.

OBJECTIVES: Our objectives were to determine the effect of dual therapy with omeprazole and amoxicillin and of triple therapy with omeprazole, amoxicillin, and metronidazole in the eradication of Helicobacter pylori (HP) and to study the long-term results of eradication in these patients. METHODS: A prospective, randomized, controlled trial was performed. Patients who were recruited had unequivocal evidence of HP infection based on culture, histology, rapid urease test, and Gram's stain of a tissue smear. Eradication was defined as the absence of bacteria in all tests performed on both corpus and antral biopsies. RESULTS: The infection was eradicated in 15 of 19 (78.9%) patients randomized to receive dual therapy and in 19 of 22 (86.4%) patients who received triple therapy. We followed the course of 30 patients in whom HP had been eradicated for a prolonged term (up to 12 months). All remained clear of HP. Twenty-five of 28 patients (89.3%) with duodenal ulcers in whom HP was successfully eradicated remained healed at 12 months. Fewer side effects were reported among patients who received the dual therapy. CONCLUSIONS: Combination therapy with omeprazole and amoxicillin with or without metronidazole is effective in the eradication of HP. In particular, the dual therapy regimen with amoxicillin is not only effective but is also well tolerated by patients.

Adult↗

A morbidity review of children with complete unilateral cleft lip nose at 10 +/- 1 years of age.

A retrospective study of morbidity due to primary radical nasal correction was undertaken on 33 consecutive cases of complete unilateral cleft lip and palate within one year of their 10th birthday. Primary surgery was performed by one surgeon (RWP) using the Alar Leapfrog technique. Morbidity was assessed by the number of manoeuvres required for revisional surgery up to the age of 10 and was derived from the case notes. A total of 12 patients required no revision. The number of revisional manoeuvres was 39 in 27 anaesthetic sessions. Cleft lip noses treated by a technique of primary radical nasal correction (Alar Leapfrog) required a significant number of secondary manoeuvres to produce an acceptable result. This must be balanced against reduced teasing due to improved symmetry over this period.

Child↗

Acquired tracheo-oesophageal fistula following tracheal intubation in a burned patient.

A 27-year old male sustained a 60 per cent TBSA burn with inhalation injury following a road traffic accident. He developed respiratory distress on day 3 postburn, and was intubated and ventilated. He was noted to have greenish aspirate from his trachea on day 17 of ventilation. He succumbed from sepsis and died on day 21 post injury. At post-mortem, a large tracheo-oesophageal fistula (TOF) was found at the level of the cuff of the nasotracheal tube.

Adult↗

Congenital tuberculosis.

A neonate presented with poor feeding, jaundice and hepatosplenomegaly. He was in liver failure with disseminated coagulopathy. Post-mortem liver biopsy revealed discrete granulomas with central necrosis and acid-fast bacilli on Ziehl-Nielsen's stain. The mother had active tuberculosis at delivery. The principal characteristics of congenital tuberculosis are reemphasized in this observation.

Adult↗

Pharmacokinetics of cyclosporine in heart and lung transplant candidates and recipients with cystic fibrosis and Eisenmenger's syndrome.

OBJECTIVE: To compare the pharmacokinetics of cyclosporine in patients with either cystic fibrosis or Eisenmenger's syndrome. METHODS: Patients in the study were heart and lung transplant candidates with either cystic fibrosis (n = 6) or Eisenmenger's syndrome (n = 5), as well as patients who received heart and lung transplantation for either cystic fibrosis (n = 13) or Eisenmenger's syndrome (n = 7). This was no experimental pharmacokinetic study in transplant candidates and an exploratory population pharmacokinetic study in transplant recipients. RESULTS: Patients with cystic fibrosis showed higher blood cyclosporine clearance, higher apparent oral clearance, shorter mean residence time, and more erratic absorption. The coefficient of variation of pharmacokinetic parameters was higher in patients with cystic fibrosis. There were no significant differences in metabolite indexes between the two groups of patients after either oral or intravenous administration. A significant negative correlation was found between cyclosporine clearance and hematocrit (r = 0.81 [95% confidence interval, -0.95 to -0.4.1]). Dose-normalized predose blood concentration measurements were lower in patients with cystic fibrosis after transplantation. There was a significant correlation between hematocrit and log dose-normalized cyclosporine concentration (r = 0.40 [95% confidence interval, 0.30 to 0.49]). The total daily dose per 100 ng/ml trough blood concentration required was estimated to be 2.36 times (95% confidence interval, 1.96 to 2.84) higher in patients with cystic fibrosis. CONCLUSIONS: Cyclosporine pharmacokinetics is more variable in patients with cystic fibrosis. The difference in cyclosporine clearance between the two groups is accounted for by differences in binding in blood rather than metabolism. The findings suggest that patients with cystic fibrosis could be conservatively given initial oral doses that are 1.5 times higher than those for patients who receive transplants because of Eisenmenger's syndrome.

Adult↗

A frameless stereotactic approach to neurosurgical planning based on retrospective patient-image registration. Technical note.

A frameless stereotactic device interfacing an electromagnetic three-dimensional (3-D) digitizer to a computer workstation is described. The patient-image coordinate transformation was found by retrospectively registering a digitizer-derived model of the patient's scalp with a magnetic resonance (MR) imaging-derived model of the same surface. This procedure was performed with routine imaging data, eliminating the need to obtain special-purpose MR images with fiducial markers in place. After patient-image fusion was achieved, a hand-held digitizing stylus was moved over the scalp and tracked in real time on cross-sectional and 3-D brain images on the computer screen. This device was used for presurgical localization of lesions in 10 patients with meningeal and superficial brain tumors. The results suggest that the system is accurate enough (typical error range 3 to 8 mm) to enable the surgeon to reduce the craniotomy to one-half the size advisable with conventional qualitative presurgical planning.

Adult↗

Growing skull fractures.

Two recent cases of growing skull fractures are presented and the literature reviewed. Skull fractures in children which are at risk of enlarging should be recognised and followed up closely.

Arachnoid Cysts↗

Tuberculosis of the thyroid gland--a review.

A review of the literature reveals that tuberculosis of the thyroid gland is a very rare condition. Only one case was notified in Singapore over the last ten years. It can occur either as part of a miliary spread or as a primary lesion in the thyroid. It is difficult to diagnose clinically and the thyroid enlargement is often mistaken for carcinoma, suppurative abscess or a haemorrhage into a thyroid cyst. Signs and symptoms are variable, and are mostly related to enlargement of the gland. Thyroid dysfunction is rare. Diagnosis is made by histological examination and demonstration of the tubercle bacilli from biopsy or aspiration specimen.

Antitubercular Agents↗