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D M Gibb

Publications and source records attributed to D M Gibb.

At least 19 recordsLinked to original sources
PubMed1999

Selective versus universal antenatal HIV testing: epidemiological and implementational factors in policy choice.

OBJECTIVE: To develop an epidemiological basis for economic analyses of selective and universal antenatal screening strategies, and to apply it to the UK. METHODS: The prevalence of higher-risk women and the prevalence of undiagnosed infection within groups of high-risk and low-risk women was estimated from surveillance and survey data. The numbers of women tested and the numbers of infected women who would be identified by universal and selective strategies were then calculated under a range of assumptions about the identification of higher-risk women and acceptance of testing. RESULTS: In higher-risk women estimated prevalence of undiagnosed infection was between 0.06% and 2.8%, comparing well with independent estimates. In low-risk women, estimates ranged from 0.014% in London to 0.002% in the rest of the UK. If uptake among the high-risk women was the same in selective and universal strategies, universal testing would entail testing between 7100 (London) and 50000 (rest of England) additional women to detect an additional case. However, if selective screening identified only 60% of those at high risk and achieved only 60% acceptance compared with a universal programme, then universal screening would require only 1150 additional women to identify one additional case in London, compared to 6470 in Scotland and 13140 in the rest of the UK. CONCLUSIONS: Overall prevalence does not form an adequate basis for determining screening strategy. Instead, universal screening can be justified either because the prevalence of HIV in the low-risk group is sufficiently high, or because it achieves sufficiently higher uptake relative to selective screening among those at higher risk.

Female↗
PubMed1998

Factors affecting uptake of antenatal HIV testing in London: results of a multicentre study.

OBJECTIVES: To measure the uptake of antenatal HIV testing and determine its relation to risk of HIV and to screening practices. DESIGN: Multicentre prospective questionnaire study. SUBJECTS: Pregnant women attending six maternity units. SETTING: Inner London, 1995-6. MAIN OUTCOME MEASURES: Uptake of testing by risk factors for HIV, ethnicity, and factors about the antenatal interview. RESULTS: All units had a "universal offer" policy for HIV testing. In five units forms were completed for 18,791 (88%) of 21,247 pregnant women. The sixth unit, where the response rate was too low to assess uptake, was excluded from the analysis. Uptake ranged from 3.4% to 51.2% (overall 22.9%), in parallel with detection of previously undiagnosed infection in pregnant women (4.9-60%). Controlling for unit, uptake was higher among the 7% who disclosed risk factors. Among those at low risk, uptake varied by ethnic group (South Asian women 9%; Latin American and Mediterranean women 33%). The relation between uptake and HIV risk category varied greatly across units. Despite increased HIV seroprevalence in black African women, uptake was similar in this group to that among women at low risk (24%). Uptake increased 2.1-fold if HIV transmission was discussed. Midwives reported spending 7 (2-15) minutes discussing HIV issues. CONCLUSIONS: Uptake of HIV testing was unacceptably low in all units, with maternity unit the strongest predictor. New approaches to antenatal HIV testing are urgently required and uptake should be audited routinely.

Africa↗
PubMed1998

Cervical length at 23 weeks of gestation: the value of Shirodkar suture for the short cervix.

OBJECTIVE: To examine the possible benefit of cervical cerclage in women with a very short cervix identified during routine sonographic assessment of cervical length at 23 weeks of gestation. METHODS: Transvaginal sonography was used to measure cervical length at 23 weeks of gestation in 2702 women with singleton pregnancies attending for routine antenatal care. In 43 (1.6%) cases the cervical length was < or = 15 mm. The 43 women in this group were referred to their obstetricians for the further management of pregnancy; in 21 cases, the pregnancy was managed expectantly and in 22 a Shirodkar suture was inserted under spinal anesthesia. The two groups were compared in terms of patient characteristics and pregnancy outcome. RESULTS: The 22 patients that were treated with cervical cerclage were not significantly different from the 21 given expectant management in ethnic origin, ponderal index, cigarette smoking or past obstetric history. The median cervical length was 10 mm in both groups. In the cervical cerclage group, 21 delivered after 32 weeks and one (5%) had spontaneous onset of labor and delivery before 32 completed weeks; all 22 infants survived. In the expectant management group, 11 (52%) had spontaneous onset of labor and delivery before 32 weeks; 20 infants survived but one baby died in the neonatal period. CONCLUSIONS: In women with a cervical length of < or = 15 mm at 23 weeks there is a more than 50% chance of spontaneous delivery at less than 32 weeks. Insertion of a Shirodkar suture in women with a very short cervix may be associated with a ten-fold reduction in risk for such early delivery.

Cervix Uteri↗
PubMed1998

Performance of antenatal HIV screening strategies in the United Kingdom.

BACKGROUND: In 1996 only 13.5% of previously undiagnosed HIV infected women were detected in pregnancy. In this study, all 265 maternity units in the United Kingdom were surveyed to determine the relation between screening strategy, uptake of testing, and detection rate. METHODS: Data on HIV screening strategy and uptake of testing were collected in 1997 by postal questionnaire. The proportion of women with previously undiagnosed HIV infection identified during pregnancy (detection rate) was calculated using data from national obstetric HIV surveillance and unlinked anonymous seroprevalence studies. RESULTS: 239 (90%) units responded; 25 of these (10%) had a universal offer strategy, 89 (37%) a selective offer, and 125 (52%) tested only women who requested it. All selective units offered testing to injecting drug users, but only 26% to women who had lived abroad in high prevalence areas. Uptake was over 10% in only eight units, all with a universal strategy, and in 76% of selective units it was below 0.1%. The detection rate was 14.7% in universal units, 7.8% in selective units, and 7.7% in on request units. In universal units, detection increased by 6.3% (95% confidence interval 3.7% to 8.8%) for every 10% increase in uptake of testing. There was evidence of both selective presentation for testing and avoidance of testing among infected women. CONCLUSIONS: All current antenatal HIV testing strategies fail to identify most infected women. Universal offer strategies achieve a very low uptake and a poor detection rate. Units with selective strategies tend to test only a minority of women at high risk and do not target all the main high risk groups.

Female↗
PubMed1997

Uptake of interventions to reduce mother-to-child transmission of HIV in the United Kingdom and Ireland.

OBJECTIVES: To describe the uptake of interventions to reduce mother-to-child transmission of HIV infection. DESIGN: Voluntary confidential reporting of HIV infection in pregnancy and childhood; telephone interview with key professionals in all London maternity units. SUBJECTS AND SETTING: HIV-infected pregnant women and children in the United Kingdom and Ireland. MAIN OUTCOME MEASURES: Trends in breastfeeding, use of zidovudine, mode of delivery and terminations of pregnancy. RESULTS: Between 1990 and 1995, 14 (4%) out of 314 women diagnosed with HIV infection before delivery breastfed compared with 109 (77%) out of 142 diagnosed after delivery. Since 1994, zidovudine use has increased in each 6-month period (14, 39, 67, and 75%; chi 2 = 17.5, P < 0.001), although in 1995 it was the policy of only 48% of London maternity units to offer zidovudine to HIV-infected women. During 1995, 44% of HIV-infected women were delivered by elective Cesarean section. Since 1990, 20% of women first diagnosed in pregnancy were reported to have their pregnancy terminated. CONCLUSIONS: Although detection of previously undiagnosed HIV infection in pregnancy remains low in the United Kingdom, and particularly in London, HIV-infected pregnant women who are aware of their status are increasingly active in taking up interventions to reduce transmission to their infants. If all HIV-infected women attending for antenatal care in London consented to testing and took up interventions and termination of pregnancy at the rates observed in this study, the number of vertically infected babies born in London each year could be reduced from an estimated 41 to 13.

Abortion, Induced↗
PubMed1997

Malignancies in UK children with HIV infection acquired from mother to child transmission.

By April 1995, 302 cases of vertically acquired HIV infection had been reported through the British Paediatric Association Surveillance Unit. Over 50% of these children had developed an AIDS indicator disease, including nine malignancies (seven cases of non-Hodgkin's lymphoma (NHL) and two of Kaposi's sarcoma). There were two other malignancies that were not AIDS indicator diseases. In children less than 5 years of age the incidence of NHL was approximately 2500 times greater than expected in the UK child population. Three children presented with NHL as their AIDS indicator disease and four developed NHL at a median of 14 (range 10-19) months after the initial diagnosis of AIDS. Six of the seven children died at a median of 6.5 (range 2-14) months after the diagnosis of NHL. The seventh child responded to treatment and is alive nearly four years later. Histology was available in five cases, of which four were of B cell and one of T cell origin. Epstein-Barr virus was detected in all three patients with NHL where it was sought; all had B cell lymphomas. Although comparatively rare, malignancies occur in children infected with HIV and may be the presenting illness. Paediatricians now need to consider HIV infection as a predisposing cause of childhood cancer, especially NHL.

Child, Preschool↗
PubMed1997

Respiratory morbidity from lymphocytic interstitial pneumonitis (LIP) in vertically acquired HIV infection.

The aim of the study was to define the respiratory morbidity caused by lymphocytic interstitial pneumonitis (LIP) in children with vertically acquired HIV infection. A retrospective case note review was performed on 95 children attending three London hospitals. Clinical and radiological evidence of LIP, acute lower respiratory tract infections, and chronic lung disease was obtained using a structured protocol. A diagnosis of LIP had been made in 33%, and an acute admission due to acute lower respiratory tract infection had occurred in 42% of all children (despite 99% taking regular cotrimoxazole prophylaxis). Admission rates because of acute lower respiratory tract infection were significantly higher in the LIP group (0.38 admissions/child year) than in the non-LIP group (0.17 admissions/child year) (p = 0.0002). Encapsulated bacteria (Streptococcus pneumoniae, Haemophilus influenzae) were most frequently isolated. Improved methods of prevention of acute lower respiratory tract infection may help to reduce the severe respiratory morbidity seen in children with LIP and HIV infection.

Acute Disease↗
PubMed1997

A family clinic--optimising care for HIV infected children and their families.

A family clinic providing specialist paediatric and adult medical, testing, counselling, and terminal care services for families living with HIV was set up at a paediatric tertiary care hospital in London in 1991. During the first five years, until April 1996, 185 children from 149 families attended, including 119 infected children, of whom 32 have died. Only 5% of mothers were born in the UK; the rest were born in 24 different countries, the majority in sub-Saharan Africa. Less than a quarter of children were cared for by both parents, 61% by mothers alone, and 11% by guardians or foster parents. Of the adult attendees, 76% were women, and more than half were untested when they first attended the clinic. Provision of a family planning service within the family clinic was initiated as a result of women presenting with unplanned pregnancies. Shared care with local clinics is increasing, but with the complexity around the management of paediatric HIV infection, particularly with regard to antiretroviral treatments, there is need for continued specialist input. Coordination among specialist and locally based family services is required to provide flexible, accessible, and up to date care for families living with HIV infection in London.

Adolescent↗
PubMed1996

Recurrent second trimester miscarriage.

Understanding the aetiology of a second trimester miscarriage allows the obstetrician to assess the recurrence risk in the next pregnancy and guides future management. Causes include anatomical abnormalities, cervical incompetence, genital tract infection, multiple pregnancy, auto-immune factors, vaginal bleeding, and fetal abnormalities. Transvaginal ultrasound of the cervix in pregnancy may have a role in the diagnosis of cervical incompetence. There is an association between genital tract infection and second trimester miscarriage, but the value of antibiotics in the prevention of miscarriage is still to be defined.

Abortion, Spontaneous↗
PubMed1995

Coverage of routine neonatal metabolic screening in children born to women known to be infected with HIV-1.

Unlinked anonymous HIV-1 testing of neonatal samples routinely collected for metabolic screening is now carried out in many parts of the United Kingdom. The purpose of this study was to assess the completeness of screening coverage in infants born to women known to be infected with HIV-1. Research nurses at family HIV clinics in three London hospitals searched for Guthrie cards from all infants born to known infected residents of North East, North West, and South West Thames regions over a 32 month period. If no card was found initially, mothers were approached for more information. Overall coverage was estimated to be 96.4% (94.6% in infants of African origin and 100% in white infants). These figures are similar to recent general population coverage estimates in inner London. We conclude that the anonymous newborn HIV testing programme is providing sufficiently accurate information on both absolute levels and time trends in maternal seroprevalence.

Africa↗
PubMed1995

Transabdominal cervicoisthmic cerclage in the management of recurrent second trimester miscarriage and preterm delivery.

OBJECTIVE: To evaluate the role of transabdominal cervicoisthmic cerclage (TCC) in the management of recurrent mid-trimester pregnancy miscarriage and preterm delivery. DESIGN: An observational study of 50 women with history of recurrent second trimester miscarriage and preterm delivery in whom TCC was performed. SETTING: A tertiary referral centre for high risk obstetrics. RESULTS: TCC was performed on 51 occasions in 50 women. One had TCC performed in two successive pregnancies. Prior to the procedure, they had experienced 36 first trimester miscarriages and 163 later pregnancy losses. These included 152 midtrimester miscarriages and 11 neonatal deaths after preterm delivery. There had been 4 survivors after preterm delivery. The total number of pregnancies after TCC was 61 with three women losing one pregnancy and subsequently having a successful pregnancy. Of these women 44 now have had a successful outcome. Six have not had a successful outcome. Eight women have had two successful consecutive pregnancies after TCC. The fetal survival was 85.2% post-procedure. CONCLUSIONS: TCC is a procedure that may be used in a highly selected group of women with anatomical defects of the cervix and previous failed transvaginal cerclage resulting in recurrent second trimester pregnancy loss and preterm birth. Strict selection criteria were applied as TCC is an invasive procedure. Although TCC is not widely used our study suggests it may be the procedure to consider in women who have had recurrent second trimester pregnancy losses and preterm births associated with cervical damage.

Abortion, Habitual↗
PubMed1995

A risk-benefit assessment of zidovudine in the prevention of perinatal HIV transmission.

Mother-to-child transmission is the main mode of acquisition of HIV infection for children, and the estimated rate of vertical transmission ranges from 15 to 20% in Europe, 15 to 25% in the US and 25 to 35% in Africa. Vertical transmission is associated with clinical and immunological progression of disease in the mother, breastfeeding and possibly with vaginal delivery. Recently, the findings of the American/French AIDS Clinical Trial Group (ACTG) trial 076 showed that in women with mildly symptomatic HIV disease and no prior treatment with antiretroviral drugs during the pregnancy, zidovudine (ZDV, 3'-azido-3'-deoxythymidine, AZT) reduced the risk of vertical transmission when administered during pregnancy and delivery and to the infant in the first 6 weeks of life. No significant adverse effects were observed in either the mothers or neonates. Although the results of the American/French trial on the use of zidovudine to prevent vertical transmission are encouraging, many questions remain unanswered. The optimal timing of administration of zidovudine is unknown, as is its effectiveness in women with clinical characteristics that differ from those of the women in the trial. Concern has been expressed about the possibility of long term effects of exposure of zidovudine during pregnancy, both for the mother and the infant (of whom 4 out of 5 are uninfected anyway) and the implications for antenatal screening. Further trials with different zidovudine regimens and other strategies to prevent vertical transmission are being planned in several countries.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Pneumocystis carinii pneumonia in vertically acquired HIV infection in the British Isles.

In order to review the clinical course, laboratory findings, and outcome of children with vertically acquired HIV infection and Pneumocystis carinii pneumonia, questionnaires were sent to paediatricians in the British Isles who had reported P carinii pneumonia and HIV infection through the British Paediatric Surveillance Unit (BPSU). Paediatric reports from the BPSU are linked to reports of pregnancies in HIV positive women and laboratory reports. P carinii pneumonia was the most frequently reported AIDS indicator disease at AIDS diagnosis, occurring in 22/56 (40%) children born in the British Isles; in a further two children P carinii pneumonia occurred after another AIDS indicator disease. The median age at P carinii pneumonia diagnosis was 4.1 (1.4-27.3) months and in 48% it occurred with other AIDS indicator diseases. Despite intensive treatment the three month survival was only 38%. The nine children surviving P carinii pneumonia subsequently developed further AIDS indicator diseases, in particular HIV encephalopathy and four have since died. P carinii pneumonia was present at AIDS diagnosis in 65% of children developing AIDS in the first year of life and caused 82% of infant deaths. Most children were not known to be at risk of HIV until they presented with P carinii pneumonia. Children with HIV infection develop P carinii pneumonia at an early age and have a poor outcome. Increased awareness of the condition is required to initiate early treatment. Prevention may be a compelling incentive for screening in pregnancy, but further study is required to quantify the risks and benefits of initiating early P carinii pneumonia prophylaxis as well as the impact this might have on life expectancy.

AIDS Dementia Complex↗