A neuropsychological investigation of dementia in motor neurone disease (MND)

Different clinical criteria for diagnosing dementia were compared in a sample of 69 patients with motor neurone disease (MND). Participants’ performances on a computerised battery of neuropsychological tests were evaluated to assess the usefulness of these tests in predicting dementia in MND. The results indicated that when diagnostic criteria for frontotemporal (FTD) were used as part of a questionnaire method of diagnosing dementia the incidence of dementia in MND was considerably greater than traditional estimates suggest. Through a series of logistic and multiple regressions the results demonstrated that neuropsychological test performance related well to diagnostic classifications of dementia. MND patients with a clinical diagnosis of dementia were likely to demonstrate impaired new learning; poor working memory and planning; slowness in information processing and rigidity in thinking. These features, which are typical of cases of FTD, suggest that the dementia of MND is usefully characterised as a form of FTD. The finding that neuropsychological impairment correlated with behavioural features of dysexecutive impairment in daily living, indicates that the management focus in MND must be broadened to include cognitive/behavioural issues.     

Benign childhood epilepsy with centrotemporal spikes: is it always benign?

Most children with benign childhood epilepsy with centrotemporal spikes have few seizures, and some have only one. We describe two children with interictal and ictal findings consistent with this epileptic syndrome but with severe intractable seizures and cognitive decline that resulted in consideration for epilepsy surgery. Spontaneous remission occured in one child; the other is still young. Despite the high seizure burden and cognitive decline, surgical consideration should be withheld, as these seizures are likely to remit.     

Cutaneous Rosai-Dorfman disease--a pathologic review of 2 cases

Rosai-Dorfman disease, also known as sinus histiocytosis with massive lymphadenopathy, is a rare but distinct clinicopathologic entity characterised histologically by a benign s histiocytic proliferation. Isolated involvement of extranodal sites without concomitant nodal disease is rare. We describe the pathological features of 2 cases of Rosai-Dorfman disease that were clinically confined to the skin. In both male adult Chinese patients, proliferation of histiocytes was accompanied by S-100 protein expression demonstrated immunohistochemically within the histiocytes. The pathology of Rosai-Dorfman disease and its microscopic differential diagnoses are discussed.     

Fatal meningoencephalitis due to Bacillus anthracis

Abstract: We report the first case of fatal anthrax meningoencephalitis in Hong Kong over the past 60 years. A 13 year-old boy presented with right lower quadrant pain, diarrhoea and progressive headache. Lumbar puncture yielded gram positive bacilli initially thought to be Bacillus cereus, a contaminant. He was treated with ampicillin and cefotaxime, but died 3 days after hospitalization. The organism isolated from blood and cerebrospinal fluid was later identified as Bacillus anthracis.     

Focal nodular hyperplasia: an unusual liver mass in a paediatric patient

We report an unusual case of focal nodular hyperplasia (FNH) occurring in a 19-month-old female without a typical central fibrous scar. Ultrasound demonstrated a solid, hypoechoic, highly vascular mass situated in the left lobe of the liver. Computed tomography showed a solid mass with no evidence of a central fibrous scar. A hepatic angiogram demonstrated enlarged right and left hepatic arteries supplying the vascular tumour, with early venous drainage into the inferior vena cava; a feature which has not been previously described. Surgical resection was carried out and a solid, nodular tumour measuring 9 x 4 x 4 cm was removed. The diagnosis of FNH was made histologically. The characteristic imaging findings of FNH will be discussed and a review of the literature of FNH in children will be presented.     

A prospective study of methylenetetrahydrofolate reductase and methionine synthase gene polymorphisms, and risk of colorectal adenoma

We examined the relationship between a functional polymorphism (667C-- >T, ala-->val) of the methylenetetrahydrofolate reductase gene (MTHFR) and the risk of colorectal adenomas in the prospective Nurses' Health Study. Among 257 incident polyp cases and 713 controls, the MTHFR val/val polymorphism [relative risk (RR) = 1.35, 95% confidence interval (CI) 0.84-2.17] was not significantly associated with risk of adenomas. This lack of association was observed for both small (RR = 1.36, 95% CI 0.76-2.45) and large (RR = 1.32, 95% CI 0.66-2.66) adenomas. Furthermore, there was no significant interaction between this polymorphism and consumption of either folate, methionine or alcohol. We also examined the relationship of a newly identified polymorphism (asp919gly) of the methionine synthase gene (MS) with the risk of colorectal adenomas in the same population. The MS gly/gly polymorphism was also not significantly associated with risk of colorectal adenomas (RR = 0.66, 95% CI 0.26-1.70). These results, which need to be confirmed in other studies, suggest that the MTHFR val/val polymorphism, which has been previously inversely associated with risk of colorectal cancer, plays a role only in a late stage (adenoma-- >carcinoma) of colorectal tumorigenesis, and/or may protect against malignant transformation in the subset of benign adenomas, which may progress to malignancy.      

Delay times and management of acute myocardial infarction in indigenous and non-indigenous people in the Northern Territory

OBJECTIVES: To investigate differences in presentation and management of Indigenous and non-Indigenous patients hospitalised with acute myocardial infarction (AMI). DESIGN: Retrospective review of hospital medical records. PARTICIPANTS AND SETTING: 122 patients with definite or possible AMI admitted to hospitals in the Top End of the Northern Territory (NT) in 1996. MAIN OUTCOME MEASURES: Percentage receiving thrombolytic therapy; delays from symptom onset to primary and emergency department presentations, first and diagnostic electrocardiograms, thrombolytic therapy and aspirin; drugs prescribed during hospitalisation. RESULTS: Thrombolytic therapy was given to 12/41 Indigenous patients (29%) and 38/81 non-Indigenous patients (47%) (P = 0.06). Presentation delay over 12 hours was the reason for not giving thrombolytic therapy for 14/29 Indigenous patients (48%) and 8/43 non-Indigenous patients (19%) (P < 0.01). Median delay times were longer for Indigenous patients for all six categories of delay, although the difference was significant only for delay to emergency department presentation (10:00 versus 3:26 hours; P < 0.01) and to diagnostic electrocardiogram (8:10 versus 3:50 hours; P < 0.01). Delays were also longer for patients from rural compared with urban areas. Once diagnosed, Indigenous patients were as likely as non-Indigenous patients to receive aspirin (93% versus 96%) and beta-blockers (70% versus 69%) and more likely to receive angiotensin-converting enzyme inhibitors (60% versus 40%; P = 0.03). CONCLUSIONS: Delays in presentation affect Indigenous people living in rural and urban areas as well as non-Indigenous people living in rural areas. Concerted efforts are needed to improve health service access in rural areas and to encourage Indigenous people with persistent chest pain to present earlier.     

Towards a pain-free venepuncture

A randomised, prospective trial was conducted to assess the efficacy of various means of alleviating the pain of subcutaneous lidocaine infiltration. One hundred and twenty-two patients were randomly allocated to different groups to receive buffered lidocaine 1%, warmed lidocaine 1% or infiltration by the counter-irritation technique. A visual analogue pain score was recorded at different stages of cannulation and results showed that pain scores were significantly lower in the group receiving buffered lidocaine 1% (p < 0.02) and in the counter-irritation group (p < 0.05). Thus buffering lidocaine 1% and administration of lidocaine 1% by the counter-irritation technique is effective in relieving the pain of lidocaine infiltration.     

Influence of respiration and portal pressure on transabdominal duplex Doppler ultrasound measurement of portal blood flow: a porcine model for experimental studies

Transabdominal duplex Doppler ultrasonography (TDDU) is commonly used for measuring hepatic blood flow (HBF) in clinical practice. Flow velocity and the cross-sectional area (CSA) of vessels are obtained separately and used to compute blood flow. Respiration and changes in portal pressure are known to cause variations in the CSA of the portal vein, but the impact of these parameters on TDDU measurement of portal blood flow is unclear. Eight Yorkshire pigs (20.7-25.1 kg) were used for the study. TDDU determination of portal blood flow was carried out using CSA of the portal vein obtained at inspiration (maximal) and at expiration (minimal) for computation, and the differences obtained were compared. Determination of HBF was carried out simultaneously on the same animals using diisopropyliminodiacetic acid (DISIDA) clearance. A physiological increase in portal pressure was then created by 50% hepatectomy and TDDU measurement similarly carried out on the second postoperative day. Computing portal blood flow in the intact liver using maximal and minimal CSA gave rise to a mean difference of 7.0 ml kg(-1) min(-1) (P < 0.001). A significant correlation was obtained between HBF and portal flow computed from maximal CSA (Pearson's correlation = 0.85, P < 0.033). The respiratory index of the portal vein (maximal CSA/minimal CSA) decreased from 1.5 to 1.2 after hepatectomy, which also caused a 90% increase in portal pressure. Respiration and portal pressure thus significantly impact on TDDU determination of HBF, and in this porcine model, computation using maximal CS more accurately reflects HBF.