Aciclovir or ganciclovir universal prophylaxis of cytomegalovirus infection in liver transplantation: an economic analysis.

BACKGROUND: Cytomegalovirus (CMV) following orthotopic liver transplantation can result in significant morbidity and mortality. Prophylaxis with oral aciclovir (ACV) or ganciclovir (GCV) for all transplant recipients (universal prophylaxis) may be beneficial, but which agent is more cost-effective is unknown. METHODS: A single centre, retrospective study of all patients who had OLT at the Western Australian Liver Transplantation Service was performed. Patients received ACV from 1992 to 1998, and GCV from 1999 to 2001. A comparative cost-effectiveness analysis for the two groups was performed based on the mean total cost of the number of cases of CMV infection and disease as the clinical end-point. RESULTS: The ACV group comprised of 55 patients and there were 24 in the GCV group. The incidence of CMV disease was 7% and 4% for the ACV and GCV groups, respectively (P > 0.05). For CMV infection it was 16% and 8%, respectively (P > 0.05). GCV prevented more cases of CMV infection and disease than ACV but at an incremental cost of dollars A20,000 (dollars US10,172) per case prevented. Overall, ACV was more cost-effective than GCV by dollars A2200 (dollars US1119) per person. The cost benefit of ACV was derived principally through a reduced pharmaceutical cost. Both agents were well tolerated without development of antiviral resistance. CONCLUSIONS: Universal prophylaxis of CMV infection-following liver transplantation with aciclovir is more cost-effective than with ganciclovir.

Second trimester screening for Down's syndrome: 7 years experience.

OBJECTIVES: To evaluate the effectiveness of the first 7 years of a programme for second trimester antenatal screening for Down's syndrome, using alpha-fetoprotein (alphaFP) and total human chorionic gonadotropin (hCG) as maternal serum markers. METHODS: A clinical biochemistry laboratory providing a screening service for four obstetric units. Women attending for antenatal care who accepted an offer of serum screening for Down's syndrome were tested between 15 and 20 weeks gestation. Down's risk estimates were calculated using maternal serum alphaFP and total hCG results as modifiers of the maternal age related risk. Outcome was determined in collaboration with the regional cytogenetics unit. RESULTS: In 7 years 66,631 women were screened, in whom 108 Down's syndrome pregnancies were identified. Risks for Down's syndrome were reported without a specified cut off recommendation; however, at a cut off of 1 in 250, 72 (66.7%) of the affected pregnancies were screen positive, the false positive rate was 5.8%, and the uptake of amniocentesis 71.2%. The detection rate was higher in women screened before 17 weeks (70.5%) than in those screened at 17 weeks or later (56.7% overall and 20.0% in those under 30 years). The uptake of screening declined gradually from 84% in 1992 to 59.5% in 1998. CONCLUSIONS: Two marker screening using aFP and total hCG is an effective way of screening for Down's syndrome and is widely accepted in the local community. Detection rates were comparable with other second trimester studies using two markers including both total and free beta hCG.

First report of oil cavities in Scrophulariaceae and reinvestigation of air spaces in leaves of Leucophyllum frutescens.

Conspicuous air spaces in Leucophyllum (Scrophulariaceae; Leucophylleae) leaves have been suggested to be developmentally transformed secretory cavities. We reinvestigated air space development in Leucophyllum frutescens, using freehand sections of mature fresh leaves and paraffin sections of several leaf stages. Each of the numerous air spaces per leaf forms because greater separation occurs within a local group of spongy mesophyll cells than in the developing spongy mesophyll elsewhere. We found no anatomical evidence of transitory epithelial cells or lysis of cells in developing air spaces, thus the hypothesis that air spaces are transformed secretory cavities is not supported. However, an important finding was that all leaves had one pair of conspicuous true secretory cavities flanking the midvein at the apex, each lined by an epithelium and filled with oil. We also found conspicuous apical cavities in freehand sections of herbarium specimens of this and three other Leucophyllum species. Cavities were not seen in L. revolutum or in the related Eremogeton grandiflorus. This is the first report and description of a true internal secretory cavity in Scrophulariaceae. In the related family Myoporaceae, we found epithelium-lined cavities scattered abundantly in leaves of cleared samples of three genera.

Down's syndrome screening using free beta hCG: instability can significantly increase the Down's risk estimate.

The stability of free beta hCG (human chorionic gonadotrophin) was assessed using a dual alpha-fetoprotein and free beta hCG assay. A significant increase in free beta hCG concentration was observed in heparinized samples left unseparated for 24 h or more, the mean increase in 21 samples being 10.2% after 24 h (P = < 0.001), increasing to 45.7% after 96 h. Similar results were also obtained in clotted samples. The effect of the increase in free beta hCG on the Down's risk estimate was calculated to assess the impact of delayed sample transport and separation. The Down's risk increased in all samples with increasing separation time, but this was most significant in two samples where, using a cut off of one in 250, the risk classification changed from low risk to high risk. These results suggest that delayed sample separation can have a significant effect on screening programmes using free beta hCG, particularly with respect to those patients whose risk classification is changed.

Screening for Down's syndrome: the first two years experience in Bristol.

OBJECTIVES: To evaluate the effectiveness of a programme for antenatal screening for Down's syndrome using alpha fetoprotein and total human chorionic gonadotrophin as maternal serum markers. SETTING: A district general hospital providing a screening service to a local purchasing authority and (under contract) to another purchasing authority in the same region. METHODS: Patients were counselled and screened between 15 and 20 weeks gestation and Down's risk estimates calculated using the maternal serum marker results as modifiers of the age related risk. Outcome was determined in collaboration with the Regional Cytogenetics Unit. OUTCOME MEASURES: Detection rate for Down's syndrome, false positive rate, uptake of screening, and uptake of amniocentesis. RESULTS: In two years 22816 women were screened (approximately 84% of population); 32 Down's pregnancies were identified, 19 (59.4%) had a reported risk of > or = 1:250 and 20 (62.5%) a reported risk of > or = 1:300. Of those screened before 17 weeks, 16/20 (80%) had a reported risk of > or = 1: 300 compared with 4/12 (33%) of those screened later (P = 0.008); 4.64% of patients screened had reported risks > or = 1: 250 and 5.87% reported risks of > or = 1:300. Amniocentesis uptake was 70% in patients with reported risks of > or = 1:300. CONCLUSIONS: Overall the screening programme was effective but screening before 17 weeks was very much more effective than screening later.

A simplified strategy for testing thyroid function.

We assessed a new strategy for thyroid-function testing that involves simultaneous measurement of free thyroxin and thyrotropin, both in singletons, with chemiluminescent assays. Using our current strategy of measuring free thyroxin as a first-line test with selected back-up testing, the results show that, of 810 patients without previous thyroid disease, 445 received back-up tests. Of these, 345 were euthyroid, whereas 63 classified as euthyroid and not selected for further testing in fact had abnormal back-up test results. Evidently the simultaneous measurement of free thyroxin and thyrotropin with the "Magic Lite" technology greatly improves diagnostic efficiency compared with this current strategy.