Kimura's Disease: Diagnostic Challenge and Treatment Modalities.

CASE REPORT: Five cases of Kimura's disease had been treated in our centre from year 2003 to 2010. All cases were presented with head and neck mass with cervical lymphadenopathy. Surgical excision was performed for all cases. Definite diagnosis was made by histopathological examination of the resected specimens. One out of five cases developed tumour recurrence four years after resection. CONCLUSION: Surgical excision is our choice of treatment because the outcome is immediate and definite tissue diagnosis is feasible after resection. Oral corticosteroid could be considered as an option in advanced disease. However, tumour recurrence is common after cessation of steroid therapy.

Nasolacrimal relapse of nasopharyngeal carcinoma.

OBJECTIVES: To describe three rare cases of nasolacrimal relapse of nasopharyngeal carcinoma, and to discuss the route of tumour spread from nasopharynx to lacrimal system as well as the relevant computed tomography findings. CASE REPORT: We report three cases of nasolacrimal relapse in patients with previously treated nasopharyngeal carcinoma. The common initial presentations in these cases were epiphora and medial canthal swelling. The tumour spread from the nasopharynx to the lacrimal sac along the lateral nasal wall and nasolacrimal canal. Computed tomography demonstrated nasolacrimal canal invasion and osteomeatal complex obliteration by the tumour. Distant metastasis was detected in two cases. CONCLUSION: More targeted radiotherapy should be delivered to prevent under-treatment of nasopharyngeal carcinoma. Nasolacrimal relapse of nasopharyngeal carcinoma is an advanced disease with a poor prognosis.

Grisel's syndrome: a rare complication of tonsillectomy.

OBJECTIVES: To discuss the pathophysiology of atlanto-axial subluxation as a rare complication of tonsillectomy, and to discuss the important radiological findings for diagnosis and treatment planning. CASE REPORT: We report a case of post-tonsillectomy atlanto-axial subluxation, also known as Grisel's syndrome, in a child. On the third day after surgery, the boy presented with torticollis with no neurological deficit. Rotatory atlanto-axial subluxation was clearly shown in computed tomography scans of the neck. Cervical traction for one week successfully reduced the subluxation, with no long-term sequelae. CONCLUSION: Pre-existing cervical ligamentous laxity and post-operative infection are believed to be the main causes of Grisel's syndrome. Although it is rare, patients are advised to seek treatment early if any neck pain or fever persists. Early diagnosis is important for better treatment outcome. Initial conservative measures are advised before more invasive cervical traction is adopted.

Prospective, randomized, controlled trial comparing lightweight versus heavyweight mesh in chronic pain incidence after TEP repair of bilateral inguinal hernia.

BACKGROUND: This prospective, clinical, randomized, controlled study was performed to define the incidence of chronic pain after total extraperitoneal (TEP) repair with a light-weighted mesh compared with heavyweight mesh in patients with bilateral inguinal hernias. METHODS: Consecutive patients with bilateral inguinal hernias were recruited for TEP inguinal hernia repair under general anesthesia. Heavyweight mesh was randomly assigned to one side of the groin and lightweight mesh to the other. Patients were followed up regularly for up to 1 year by an independent surgeon who was unaware of the mesh assignment. The postoperative pain score by means of a visual analogue scale (VAS) and other data were recorded. RESULTS: Fifty bilateral TEP hernia repairs were performed between September 2007 and February 2009. Six patients (12%) complained of chronic pain 3 months after the operation. A higher average pain score was observed for the side of hernia repaired by heavyweight mesh compared with lightweight mesh, but the difference was not statistically significant. More patients complained about foreign body sensation on the side repaired with heavyweight mesh (24%) compared with the side with lightweight mesh (8%; P < 0.05). There was no recurrence or need for reintervention for either type of mesh. CONCLUSIONS: Lightweight polypropylene mesh may be preferable to heavyweight mesh for TEP inguinal hernia repair because it provides less postoperative foreign body sensation; however, there was no significant difference in the incidence of chronic pain.

Argon plasma coagulation for blue rubber bleb nevus syndrome in a female infant.

We report on the case of an 8-month-old baby with blue rubber bleb nevus syndrome (BRBNS) presenting with recurrent bleeding from multiple haemangiomas in the colon and rectum. Treatment with Argon plasma coagulation resulted in long-term success. Our case is unique in that 1) it is the first documented case treated by argon plasma coagulation; 2) it is only the second case in the world literature with involvement of the genital tract; 3) it is the youngest patient treated endoscopically to date; 4) it is the endoscopically treated case with the longest follow-up; 5) it represents the second case of BRBNS reported from this part of the world; and 6) it expands the spectrum of mucosal lesions amenable to this new form of treatment. Argon plasma coagulation is a simple, inexpensive and effective treatment for selected lesions in BRBNS.

Determination of bioactive diterpenoids from Andrographis paniculata by micellar electrokinetic chromatography.

The present paper describes the development of a micellar electrokinetic chromatographic (MEKC) method for simultaneous determination of andrographolide, deoxyandrographolide and neoandrographolide in ethanol extracts of Andrographis paniculata. Separations were carried out in a fused-silica capillary tube with UV detection at 214 nm. Good separation was achieved using a 20 mM borate buffer, containing 20 mM sodium dodecyl sulphate and 10 mM sodium cholate, adjusted to pH 8.3 at an operating voltage of 25 kV, temperature of 35 degrees C and a hydrodynamic injection of 5 s. The method was validated with good correlation coefficients obtained (0.9986-0.9989) while relative standard deviation (RSD) of migration time was between 1.14 and 2.42. It is concluded that this method could be used for speedy and accurate qualitative and quantitative analysis of bioactive diterpenoids in andrographis herb and its derived products.

Topiramate-induced metabolic acidosis: report of two cases.

Two children who presented with symptomatic metabolic acidosis after being put on topiramate (TPM) are reported. The first patient was an 11-year-old male with refractory complex partial epilepsy who was put on TPM for 13 months. He developed hyperventilation 1 week after increasing the dose to 300 mg/day. Arterial blood gas revealed hyperchloraemic metabolic acidosis with partial respiratory compensation: pH 7.36, PCO2 27.2 mmHg, bicarbonate 14.9 mEq/L, base excess -8.9 mmol/L. Hyperventilation and acidosis resolved after administration of sodium bicarbonate and reduction of the dose of TPM. The second patient was a female who developed increasing irritability at age 16 months and 21 months, each time associated with introduction of TPM and resolved promptly upon withdrawal of the drug. Venous blood gas taken during the second episode revealed pH 7.34, PCO2 37.4 mmHg, bicarbonate 20.4 mEq/L, base excess -4.2 mmol/L. The predominant mechanism of TPM-induced hyperventilation involves inhibition of carbonic anhydrase at the proximal renal tubule, resulting in impaired proximal bicarbonate reabsorption. The occurrence of hyperpnoea or mental status change in any patient who is on TPM should prompt an urgent blood gas sampling, with correction of the acid-base disturbances accordingly.

Atypical presentation of dopa-responsive dystonia: generalized hypotonia and proximal weakness.

Dopa-responsive dystonia (DRD) is an autosomal dominant disorder typically presenting as dystonia with diurnal variability. Described is an 8-year-old boy who had had waddling gait, generalized hypotonia, and proximal weakness since early childhood. He responded well to low-dose L-dopa. He had a point mutation of the GTP cyclohydrolase I gene. The patient's father and sister had the same mutation but did not have proximal weakness. GTP cyclohydrolase I deficiency can present with hypotonia and weakness.

Valproic acid and thrombocytopenia: cross-sectional study.

OBJECTIVE: To investigate the relationship between platelet count and serum valproic acid level, age, duration of valproic acid therapy, and polytherapy, and to determine the clinical significance of thrombocytopenia associated with high-dosage valproic acid therapy. DESIGN: Cross-sectional study. SETTING: Residential unit for neurologically impaired children and paediatric out-patient clinic, Hong Kong. PATIENTS: Ninety-six neurologically impaired children who were treated with valproic acid between 1 July 1991 to 3 June 1999. The comparison group consisted of 48 children receiving antiepileptic drugs other than valproic acid. INTERVENTION: Low- or high-dosage valproic acid, using the threshold value of 40 mg/kg/d. MAIN OUTCOME MEASURES: Platelet count and liver function, duration of valproic acid treatment, dosage, and trough serum valproic acid concentration. RESULTS: Seventeen (17.7%) patients in the treatment group developed thrombocytopenia, compared with two (4.2%) in the comparison group (P<0.05). The platelet count was negatively correlated to serum valproic acid level and age, and positively correlated to polytherapy. The duration of valproic acid treatment was not a confounding factor in the age-related decrease in platelet count. Children with a trough level of >450 micromol/L or a daily dose of >40 mg/kg were more likely to develop thrombocytopenia. Thrombocytopenia was mild in most cases. CONCLUSIONS: A trough valproic acid level of >450 micromol/L or a daily dose of >40 mg/kg should alert the clinician to the risk of developing thrombocytopenia. The risk is further increased for older children. The platelet count should be monitored for patients receiving a high concentration of valproic acid who are also receiving drugs that would affect homeostasis, or who are undergoing surgical procedures.

Epidemiology of headache in Hong Kong primary-level schoolchildren: questionnaire study.

OBJECTIVE: To collect and analyse epidemiological data on childhood headache in the Hong Kong community. DESIGN: Questionnaire study. SETTING: Three primary schools, Hong Kong. PARTICIPANTS: Two thousand, one hundred and twenty pupils from 2156 replied to the questionnaire survey. One hundred and twenty-four pupils who were identified to have suspected recurrent headache were invited to a follow-up medical consultation. MAIN OUTCOME MEASURES: Age-groups and prevalence of tension-type and migraine headache, using the diagnostic criteria of the International Headache Society. RESULTS: The overall prevalence of headache in the 2120 respondents was 2.8%. The prevalence of tension-type headache, migraine, probable migraine, and unclassified headache were 1.2%, 0.5%, 0.7%, and 0.5%, respectively. The age-specific prevalence of headache from the age of 6 to 13 years showed a steadily increasing trend from childhood to the early teens. CONCLUSION: Headache is a common complaint for children, although it may be underrecognised. Further study will be beneficial for providing better management of headache in this population.

Classic late infantile neuronal ceroid lipofuscinosis in a Chinese patient.

Neuronal ceroid lipofuscinoses are a group of rare neurodegenerative disorders that are characterised by an accumulation of autofluorescent lipopigments in neurons and extraneuronal tissues. We report on a 4-year-old boy who presented with an acute onset of seizures followed by rapid psychomotor deterioration, ataxia, and visual failure. Photic stimulation at 1 to 3 Hz elicited discrete spike and wave discharges in the electroencephalogram, which were diminished at a higher frequency of stimulation. The electroretinogram was extinct. Magnetic resonance imaging of the brain showed generalised cerebral and cerebellar atrophy. Electron microscopic examination of lymphocytes and samples of muscle and skin revealed characteristic curvilinear inclusion bodies. To our knowledge, this is the first case of late infantile neuronal ceroid lipofuscinosis to be reported in a Hong Kong Chinese patient.

Ictal (99m)Tc ECD SPECT in paroxysmal kinesigenic choreoathetosis.

Paroxysmal kinesigenic choreoathetosis is a rare neurologic disorder characterized by sudden attacks of brief involuntary dyskinetic movement that are precipitated by voluntary movement. A 14-year-old male who presented with frequent brief attacks of hemidystonia triggered by sudden movement is reported. Investigations, including video electroencephalogram and magnetic resonance imaging of brain, were normal. There was excellent and sustained response to carbamazepine. Ictal single-photon emission computed tomography using (99m)Tc ethyl cysteinate dimer revealed increased perfusion of the contralateral basal ganglia, which is associated with onset of choreoathetosis attacks. Our findings provide evidence that hyperactivity of the basal ganglia is associated with the dyskinetic attacks in paroxysmal kinesigenic choreoathetosis.

De novo mutation in the mitochondrial tRNALeu(UUR) gene (A3243G) with rapid segregation resulting in MELAS in the offspring.

A 14-year-old Chinese boy with a normal perinatal and early developmental history presented at 5 years of age with migraine, intractable epilepsy, ataxia, supraventricular tachycardia, paralytic ileus and progressive mental deterioration. Computerized tomography revealed multiple cerebral infarcts in the parieto-occipital region without basal ganglial calcification. Magnetic resonance imaging showed increased signal intensity in T2 weighted images in the same regions. A cerebral digital subtraction angiogram was normal. Venous lactate, pyruvate, lactate to pyruvate ratio and cerebrospinal fluid lactate were elevated. Muscle biopsy did not reveal any ragged red fibres; dinucleotide-tetrazolium reductase activity was normal. Mitochondrial DNA analysis detected an adenine to guanine mutation at nucleotide position 3243 of tRNALeu(UUR). All four tissues analysed demonstrated heteroplasmy: leucocyte 56%, hair follicle 70%; buccal cell 64%; muscle 54%. The mother and brother of the proband, both asymptomatic, were also found to have a heteroplasmic A3243G mutation in the leucocytes, hair follicle and buccal cells. Other members of the maternal lineage, including the maternal grandmother, did not have the mutation. This report describes a patient with mitochondrial encephalopathy, lactic acidosis, stroke-like episodes, who presented with multisystem involvement. The absence of ragged red fibres in muscle biopsy did not preclude the diagnosis. Mutational analysis of mitochondrial DNA conveniently confirmed the diagnosis of the disorder. A de novo mutation is demonstrated in this family.

Visual field plasticity in a female with right occipital cortical dysplasia.

Brain plasticity refers to its ability to recover after damage. Visual field plasticity is not well recognized. We report a 12-year-old female who first presented with recurrent seizures and was subsequently found to have a large, right occipital cortical dysplasia on magnetic resonance imaging. Her visual field by Goldmann perimetry was totally normal. Visual-evoked potential studies revealed the left hemifield P100 response was detected maximally at the right temporal and parietal regions. A weak but reproducible right hemifield P100 response was located at the right medial skull base. Functional magnetic resonance imaging with flashlight stimulation revealed cerebral activity mainly at the right posterior temporal and parietal lobes and left occipital lobe. These studies suggested that the left hemifield function was located at the right posterior temporal and parietal lobes. The left occipital lobe may also have been reorganized, with a P100 vector pointing out from its inferiomedial base. We reviewed other related reported cases. We believe that visual-evoked potential studies and visual functional magnetic resonance imaging should be performed more liberally for recognition of visual field plasticity.