Serum müllerian-inhibiting substance in Down's syndrome pregnancies

BACKGROUND: To examine whether maternal serum levels of müllerian-inhibiting substance (MIS) differ in Down's syndrome and unaffected pregnancies. METHODS: Case-control study was conducted using stored serum from an antenatal screening programme. Sera from 25 Down's syndrome pregnancies were retrieved from -20 degrees C storage together with 125 unaffected controls individually matched for maternal age, weeks of gestation and duration of storage. Results were expressed in multiples of the gestation-specific median value (MoM) in controls. RESULTS: The median value in Down's syndrome pregnancies was 0.83 MoM (P = 0.77, two-tail Wilcoxon rank sum test). Among unaffected pregnancies, there was a statistically significant correlation between MIS and pregnancy-associated plasma protein-A (P < 0.05). MIS levels were elevated in pregnancies where assisted reproduction techniques had been used. CONCLUSION: There is no evidence for a substantial reduction in maternal serum MIS levels in Down's syndrome pregnancies. This study provides useful information regarding serum MIS levels in pregnancy.     

Repeat maternal serum alpha-fetoprotein testing in antenatal screening programmes for Down's syndrome

The risk of having a Down's syndrome term pregnancy was estimated using maternal age and the results of two maternal serum alpha-fetoprotein (AFP) tests carried out between 14 and 20 weeks gestation. The estimates of risk were derived from published data and the AFP results from nine affected and 145 unaffected pregnancies in which repeat testing had been carried out. Repeat AFP testing is unjustified in antenatal screening programmes for Down's syndrome, but if a second test happens to have been done, the appropriate estimate of risk that would be applicable when counselling individual patients depends on both results. For example a woman aged 35 years and 6 months with a first AFP level of 0.50 multiples of the normal median (MoM) was estimated to have a risk of 1:172. If a second test were done on a fresh sample and the AFP level were 0.80 MoM then the estimated risk would be 1:216 which is higher than the estimated risk of 1:353 obtained if the second test were regarded as the only result. Estimates of risk are given for maternal serum AFP results in first and second tests ranging from 0.40 to 2.50 MoM.     

The influence of diabetes mellitus upon peripheral vascular disease

The treatment of 332 consecutive patients referred to a peripheral vascular unit with rest pain, ulceration or gangrene of the lower limb has been studied. Ninety-seven (20 per cent) of the patients had diabetes mellitus. Although diabetes was related to adverse limb salvage and patient survival rates, this could be accounted for by the influence of initial presenting clinical features and treatment upon survival time. The influence of these factors upon survival time was still strong even when the data were stratified for diabetric status. Thus, an extensive amputation carries the worse prognosis, with a less extensive amputation intermediate between an extensive amputation and any other form of therapy. Patients with both rest pain and ulceration or gangrene have a poor prognosis when assessed by either limb salvage or mortality. The majority of the patients with less extensive amputations are diabetic. This is related to the high incidence of localized ulceration among those in the diabetic group. In diabetics, a less extensive amputation, if clinically indicated, is worthwhile because of the low incidence of a subsequent extensive amputation after a less extensive amputation and the better survival rate for those patients with less extensive amputations as compared with those with extensive amputations.     

Antenatal screening for cystic fibrosis

Objective To assess the practicality of implementing antenatal screening for cystic fibrosis in Yorkshire.
Design Prospective study in which all pregnant women were offered testing for the AF508 mutation which accounts for about 85 % of carriers in Yorkshire. The reproductive partners of those found to be cystic fibrosis carriers were then tested and any carrier referred for genetic counselling.
Setting Antenatal clinics in two hospitals and eight general practices.
Population Six thousand and seventy-one pregnant women.
Results A total of 3773 women (62 %) accepted the screening offer. This was a lower uptake rate than in other published UK studies: Aberdeen (85–91%), Manchester (85%), Edinburgh (76–84%) and Oxford (67%). Nonetheless there were large and statistically significant differences in the uptake rate between centres within the study: 78% and 60% for the two hospitals and 67% for the general practices. One hundred and thirty women (3.4%) were found to be carriers and three carrier couples were identified. The median time interval for the laboratory to produce a result was five days and the cost was £16 on average.
Conclusions Antenatal screening for cystic fibrosis does not pose any special practical difficulties. It would be feasible to introduce it into routine practice in Yorkshire.