Natural history of apparently isolated severe fetal ventriculomegaly: perinatal survival and neurodevelopmental outcome.

OBJECTIVE: To review the prenatal diagnosis of apparently isolated severe ventriculomegaly (SVM) in a tertiary referral fetal medicine unit and report on perinatal and neurodevelopmental outcomes. METHODS: All cases of isolated SVM referred to Fetal Medicine at the NMH between 2000 and 2008 were identified. Outcome information was obtained from detailed telephone interviews with parents and paediatric records and histopathology in cases of stillborn fetuses. RESULTS: Thirty-six cases of SVM were referred, out of which 19 were diagnosed with 'apparently' isolated SVM. Macrocrania was present in 88% at 36 weeks (mean HC 439 mm). Cephalocentesis was performed in six cases with poor prognosis. All resulted in perinatal loss. The neurodevelopmental outcome of survivors with isolated SVM (ten live-born survivors) showed major neurological morbidity in 50% (5/10) of the cases, mild morbidity in 40% (4/10) and a normal outcome in only one case. CONCLUSION: Isolated SVM had a very poor perinatal outcome with neurological and physical disability in the overwhelming majority. Only one case of the 17 (6%) diagnosed initially with 'apparently' isolated SVM was born alive without handicap. Information from our series may aid couples in decision making about pregnancy interruption and the difficult decision of prenatal or intrapartum cephalocentesis.

A comparison of Doppler flow velocity waveforms, amniotic fluid columns, and the nonstress test as a means of monitoring post-dates pregnancies.

Five hundred thirty-four pregnancies exceeding 294 days were monitored by weekly sonographic estimations of amniotic fluid columns, daily maternal recordings of fetal movements, and thrice-weekly nonstress tests. In addition, each woman received twice-weekly studies of the uteroplacental and umbilical circulations by means of Doppler ultrasound. There were no fetal deaths in the study. Of the individual methods of fetal surveillance, absence of end-diastolic frequencies in the umbilical artery was the most sensitive, predicting 91% of fetuses who developed fetal distress in the first stage. Combining the test with sonographic estimation of amniotic fluid columns improved the prediction to 100%, with only a minimal fall in the specificity. These results strongly suggest that a combination of umbilical artery Doppler waveforms and amniotic fluid determinations is an adequate method of monitoring the post-dates pregnancy.

Pathological changes in the pericardium and meninges of cattle associated with Clostridium chauvoei.

Twenty-nine cases of Clostridium chauvoei infection in cattle were investigated over a two-year period. Fourteen had lesions of myositis only, eight had lesions of both myositis and fibrinous pericarditis, six had lesions of fibrinous pericarditis only and one had lesions of purulent meningitis only. Cl chauvoei was identified in all the lesions using the fluorescent antibody technique.

An experimental study with a Leptospira interrogans serovar bratislava vaccine.

The intramuscular vaccination of pigs with two doses, two weeks apart, of a Leptospira interrogans serovar bratislava bacterin, protected pigs against renal infection when challenged with bratislava strains six weeks later but did not protect pigs challenged after 26 weeks.

Isolation of leptospires from the genital tract and kidneys of aborted sows.

Twenty sows were examined as part of an investigation into the relative importance of the genital and urinary tracts as sites of leptospiral persistence in pigs. The sows had previously either aborted leptospire-infected fetuses or aborted on farms where leptospire infection had been demonstrated in other litters. Leptospires belonging to the Australis serogroup were recovered from the upper genital tract of all the sows. In contrast, leptospires were only recovered from 75 per cent of their kidneys. Isolates from 10 of the sows were identified to serovar level: six were serovar muenchen and four were bratislava. Persistence was observed in renal and genital tissues for up to 147 days after abortion.

Prevalence of Leptospira infection in aborted pigs in Northern Ireland.

During an investigation of pig abortions and stillbirths in Northern Ireland, leptospires were isolated from 55 of the 78 litters examined. Strains belonging to four serogroups (Australis, Icterohaemorrhagiae, Hebdomadis and Autumnalis) were recovered but leptospires of the Australis serogroup accounted for 91 per cent of the isolates. Two serovars of the Australis group bratislava and muenchen, were identified.

Vaccination against Aujeszky's disease: field experiences.

Twelve herds were investigated where outbreaks of clinical Aujeszky's disease had occurred. Clinical Aujeszky's disease was eliminated from all farms following vaccination. After vaccination was stopped in two of the six fattening herds virus was also apparently eradicated, judging from serological examination. These two herds were the smallest of the six fattening farms and size and the throughput of pigs may have contributed to apparent eradication of virus. In two of six breeding farms where controlled vaccination is still practised unvaccinated gilts and boars were seronegative. In this case possible eradication of infection may have resulted from either no excretion or insufficient production of virus from vaccinates to infect susceptible non-vaccinates. It is postulated that a properly controlled and monitored vaccination and culling programme may result in the eradication of disease and perhaps also infection from breeding herds experiencing Aujeszky's disease.

Possible involvement of leptospires in abortion, stillbirths and neonatal deaths in sheep.

Using culture, immunofluorescence and fetal serology, leptospiral infection was demonstrated in aborted, stillborn and weak lambs from nine out of 42 flocks investigated during the 1980 and 1981 lambing seasons. Three serogroups of leptospira, namely the Hebdomadis, Australis and Pomona serogroups, were implicated.

Isolation of a highly pathogenic influenza virus from turkeys.

An influenza virus was isolated from turkeys with an acute disease causing 30% mortality. The virus was subtyped as H5 N8. The nomenclature A/turkey/Ireland/83 (H5 N8) is proposed for this isolate. The virus had an ICPI of 1.80 to 1.85 for 1-day-old chicks and an IVPI of 2.74 for 6-week-old chickens. Following oronasal inoculation of juvenile and adult turkeys, chickens and ducks with the isolate, 100% mortality occurred in turkeys and chickens. No clinical signs were observed in inoculated ducks, but all developed serum antibody titres against the virus.