Congenital cataract associated with persistent fetal vasculature: findings from IoLunder2.

PurposeTo describe the frequency, characteristics, and treatment outcome of persistent fetal vasculature (PFV) in children undergoing surgery for congenital and infantile cataract in the first 2 years of life.Patients and methodsObservational population-based cohort study with case identification through active surveillance and standardised data collection via a national clinical network, the British Isles Congenital Cataract Interest Group (BCCIG).ResultsThe IoLunder2 cohort comprises 246 children undergoing surgery for bilateral and unilateral congenital and infantile cataract in the first 2 years of life. A total of 58/246 (24%) children had PFV (%): overall, 46/95 (46%) with unilateral cataract, and 12/141 (8%) with bilateral disease. Anterior segment vascular remnants were more common in bilateral than unilateral disease (75 vs 11%, P=0.01). At 1 year after surgery, 20% of children with bilateral PFV and 24% with unilateral had achieved normal vision for age within the operated eye. The prevalence of post-operative glaucoma was 9% (of children with bilateral disease) and 4% (unilateral).ConclusionPFV is significantly more common than previously reported, and outcomes are comparable to that for congenital and infantile cataract overall.

Causes of certifications for severe sight impairment (blind) and sight impairment (partial sight) in children in England and Wales.

AIM: To explore and describe trends in the principal disorders/conditions ('cause') for severe sight impairment (SSI) (blind) and sight impairment (SI) (partial sight) certification in children in England and Wales since 1999. METHODS: We obtained certification data for SI and SSI from a national database for all individuals aged 16 years or less at the time of certification in England and Wales for the years 1999/2000 and for the years 2007/2008-2009/2010. RESULTS: In total, there were 861 certifications in the year 1999/2000, rising to 1040 certifications in 2009/2010. The commonest single causes of SSI certification in 1999/2000 were cerebral visual impairment (23.2%) and optic nerve disorders (23.2%). The commonest single causes of SI certification in the same year comprised nystagmus (16.7%) and optic nerve disorders (15.5%). Cerebral visual impairment was the commonest single cause of SSI in children in England and Wales annually between 2007/2008 and 2009/2010 accounting for 21%-31% of certifications. The commonest causes of SI certification in 2009/2010 were congenital globe anomalies (18.4%) and retinal dystrophy (16.6%). The proportion of SI and SSI due to optic nerve disorders has decreased since 1999/2000. CONCLUSIONS: Our findings suggest that in England and Wales, cerebral visual impairment is now the commonest cause of paediatric SSI certification and hereditary retinal dystrophy and congenital globe anomalies are the commonest causes of SI certification.

Primary cell and micromass culture in assessing developmental toxicity.

Under the European Commission's New Chemical Policy both currently used and new chemicals should be tested for their toxicities in several areas, one of which was reproductive/developmental toxicity. Thousands of chemicals will need testing which will require a large number of laboratory animals. In vitro systems (as pre-screens or as validated alternatives) appear to be useful tools to reduce the number of whole animals used or refine procedures and hence decrease the cost for the chemical industry. Validated in vitro systems exist for developmental toxicity/embryotoxicity testing. Indeed, three assays have recently been validated: the whole embryo culture (WEC), the rat limb bud micromass (MM), and the embryonic stem cell test (EST). In this article, the use of primary embryonic cell culture, and in particular micromass culture, including a relatively novel chick heart micromass (MM) culture system has been described and compared to the validated D3 mouse embryonic stem cell (ESC) test.

Cataract surgery and primary intraocular lens implantation in children < or = 2 years old in the UK and Ireland: finding of national surveys.

BACKGROUND: Current patterns of practice relating to primary intraocular lens (IOL) implantation in children < or =2 years old in the UK and Ireland are investigated. METHODS: National postal questionnaire surveys of consultant ophthalmologists in the UK and Ireland. RESULTS: 76% of 928 surveyed ophthalmologists replied. 47 (7%) of the respondents operated on children aged < or =2 with cataract. 41 (87%) of respondents performed primary IOL implantation, but 25% would not implant an IOL in a child under 1 year old. 88% of surgeons used limbal wounds, 80% manual capsulotomies, 98% posterior capsulotomies and 100% hydrophobic acrylic lenses. The SRK/T formula was most commonly used (70%). Exclusion criteria for primary IOL implantation varied considerably and included microphthalmos (64% of respondents), anterior and posterior segment anomalies (53%, 58%), and glaucoma (19%). DISCUSSION: Primary IOL implantation in children < or =2 has been widely adopted in the UK and Ireland. There is concordance of practice with regards to surgical technique and choice of IOL model. However, there is some variation in eligibility criteria for primary IOLs: this may reflect a lack of consensus on which children are most likely to benefit. Thus, there is a need for systematic studies of the outcomes of primary IOL implantation in younger children.

Presenting features and early management of childhood intermittent exotropia in the UK: inception cohort study.

AIM: To investigate factors associated with early management of intermittent exotropia (X(T)) in hospital eye departments in the UK in a prospective cohort study. METHODS: An inception cohort of 460 children aged <12 years with previously untreated X(T) (mean age 3.6 years, 55.9% girls) was recruited from 26 UK hospital children's eye clinics and orthoptic departments. Participants received a standard ophthalmic examination at recruitment and orthoptic assessment at three-monthly intervals thereafter. The influence of severity of exotropia (control measured by Newcastle Control Score (NCS), and angle of strabismus, visual acuity and stereoacuity) and age on the type of management was investigated. RESULTS: Within the first 12 months following recruitment, 297 (64.6%) children received no treatment, either for impaired visual acuity or for strabismus. Ninety-six (21%) children had treatment for impaired visual acuity. Eighty-nine (19.4%) received treatment for strabismus (22 of whom also received treatment for defective visual acuity); in 54 (11.7%) treatment was non-surgical and in 35 (7.6%) eye muscle surgery was performed. Children with poor (score 7-9) control of strabismus at recruitment were more likely to have surgery than children with good (score 1-3) control (p<0.001). Children who had no treatment were younger (mean age 3.38 years) than those who were treated (mean 4.07 years) (p<0.001). Stereoacuity and size of the angle of strabismus did not influence the type of management received. CONCLUSIONS: X(T) can be a presenting sign of reduced visual acuity. Most children with well controlled X(T) receive no treatment within 12 months following presentation.

Visual impairment due to undiagnosed refractive error in working age adults in Britain.

BACKGROUND: Detection and treatment of undiagnosed refractive error (RE), with its attendant functional consequences, is a priority of VISION 2020, the global initiative against avoidable visual disability. The authors investigated the frequency of visual impairment due to undiagnosed RE and its associations with vision-related quality of life (VRQOL), general health and social circumstances in a contemporary and nationally representative population of British working-age adults. METHODS: 9271 members of the 1958 British birth cohort had visual acuity and VRQOL assessed at 44/45 years. The authors compared those with undiagnosed RE with those with diagnosed RE, defining undiagnosed RE as >or=0.2 logMAR units/2 lines acuity improvement in both eyes with pinhole in individuals without current or prior optical treatment or ophthalmic history. RESULTS: 144/9271 (1.6%) individuals had undiagnosed and 3513/9271 (37.9%) diagnosed RE. 18% (24/144) of those with undiagnosed RE were classifiable as visually impaired. Individuals with undiagnosed RE were more likely to have a manual (vs non-manual) occupation and to be separated, divorced or widowed, and less likely to be in social or professional organisations. There is also some evidence that they are more likely to express concern, embarrassment and frustration about their eyesight and worry about coping with life. CONCLUSION: A significant proportion of working age adults in Britain appear to have undiagnosed but visually significant RE. Improvements in existing opportunities for detecting RE in adults could benefit these individuals during their working lives and avoid the serious adverse consequences associated with vision impairment in later life.

Capturing myopia and hypermetropia 'phenotypes' without formal refraction.

PURPOSE: Understanding genetic and environmental factors that together contribute to the development of myopia is an international research priority. We have investigated the feasibility and accuracy of identifying and classifying refractive error, without formal refraction, as a means of easily identifying affected individuals in a large-scale, non-ophthalmological, and population-based survey. METHODS: At age 44/45 years, members of the 1958 British birth cohort underwent a biomedical, community survey. Refractive error (autorefraction) was measured and categorised by spherical equivalent (SE) measurement; myopia (SE of -1.00 or more extreme), hypermetropia (+1.00 or more extreme), or emmetropia (-0.99 to +0.99). Lenses of prescribed distance glasses, if worn, were assessed as minifying, magnifying, or making no difference to a standard viewed image and cohort members reported on 'short' or 'long' sightedness. RESULTS: A total of 2499 cohort members, randomly selected, had formal refraction (autorefraction) and 917 (36.7%) of these individuals had their prescribed distance glasses examined. Sensitivities for myopia and hypermetropia using examination of glasses were over 80% and positive predictive values were 95 and 65% respectively whereas self-report of 'short-sightedness' or 'long-sightedness' had poor accuracy. CONCLUSION: We suggest examination of prescribed distance glasses can be an effective method of 'screening' for refractive error in the field, especially where prevalence is high.

Does amblyopia affect educational, health, and social outcomes? Findings from 1958 British birth cohort.

OBJECTIVE: To determine any association of amblyopia with diverse educational, health, and social outcomes in order to inform current debate about population screening for this condition. DESIGN, SETTING, AND PARTICIPANTS: Comparison of 8432 people with normal vision in each eye with 429 (4.8%) people with amblyopia (childhood unilateral reduced acuity when tested with correction and unaccounted for by eye disease) from the 1958 British birth cohort, with respect to subsequent health and social functioning. RESULTS: No functionally or clinically significant differences existed between people with and without amblyopia in educational outcomes, behavioural difficulties or social maladjustment, participation in social activities, unintended injuries (school, workplace, or road traffic accidents as driver), general or mental health and mortality, paid employment, or occupation based social class trajectories. CONCLUSIONS: It may be difficult to distinguish, at population level, between the lives of people with amblyopia and those without, in terms of several important outcomes. A pressing need exists for further concerted research on what it means to have amblyopia and, specifically, how this varies with severity and how it changes with treatment, so that screening programmes can best serve those who have the most to gain from early identification.

How protective is breast feeding against diarrhoeal disease in infants in 1990s England? A case-control study.

AIMS: To assess the effect of several measures of infant feeding on diarrhoeal disease, and whether these effects vary according to markers of social deprivation. METHODS: Case-control study of diarrhoeal disease cases presenting to 34 general practices in England. Controls were stratified on age group, area deprivation index for the practice, and whether or not the practice was in London. Data were available on 304 infants (167 cases and 137 controls). RESULTS: After adjustment for confounders, breast feeding was associated with significantly less diarrhoeal disease. Associations were striking even in infants aged > or = 6 months. They did not vary by social class, but were greater in those living in rented council accommodation and in more crowded households. The effect of receiving no breast milk was stronger in more deprived areas than in less deprived areas. The effect of not receiving exclusive breast milk was stronger in more deprived areas than in less deprived areas. In formula fed infants, there was significantly more diarrhoeal disease in those not sterilising bottles/teats with steam or chemicals. The protective effect of breast feeding did not persist beyond two months after breast feeding had stopped. CONCLUSIONS: Breast feeding protects against diarrhoeal disease in infants in England although the degree of protection may vary across infants and wear off after breast feeding cessation. Education about the benefits of breast feeding and the risks of inadequate sterilisation should be targeted at carers in deprived areas or households.

Impact of congenital colour vision defects on occupation.

AIMS: To investigate whether there is an association between congenital colour vision defects (CVD) and occupational choice and employment history, in order to inform the debate about the value of universal childhood screening for these disorders. METHODS: Participants were 6422 males and 6112 females from the 1958 British birth cohort, followed from birth to 33 years, whose colour vision was assessed (Ishihara test) at 11 years. RESULTS: A total of 431 males (6.7%) had CVD. Men with CVD had pursued some careers for which normal colour vision is currently regarded as essential; for example, eight men (3.1%) with CVD were in the police, armed forces, or fire-fighting service at 33 years compared to 141 men (3.8%) with normal colour vision. They were, however, under-represented compared to those with normal colour vision, in other occupations; for example, no men with CVD were employed in electrical and electronic engineering at 33 years compared to 15 men (0.4%) with normal colour vision. CONCLUSIONS: The findings of this study suggest there is little to be gained by continuing with existing school screening programmes for CVD, whose primary purpose is to advise affected children against certain careers. Other ways of informing young people about potential occupational difficulties and pathways for referral for specialist assessment are likely to be more useful.

The infectious intestinal disease study of England: a prospective evaluation of symptoms and health care use after an acute episode.

The sequelae of Infectious Intestinal Disease (IID) in a population-based sample of cases and matched controls were investigated for a period of 3 months following the initial infection. Incident cases of IID presenting to GPs or occurring in the community and controls were studied at 3 weeks and over a 3-month follow-up period. Cases were six times more likely than controls to have gastrointestinal symptoms, particularly diarrhoea, at 3 weeks. Ten per cent of cases consulted their GP in the 3 months after episode and 2.3% were referred to hospital. GP presentation rates were twice as high in cases. Gastrointestinal symptoms persist after IID, leading to an increased likelihood of GP consultation and hospital referral. Diagnosis of irritable bowel syndrome may be more likely following IID. The burden of IID is likely to be considerable given its high incidence and the frequency of such sequelae.

The study of infectious intestinal disease in England: socio-economic impact.

To assess the socio-economic impact of infectious intestinal disease (IID) on the health care sector, cases and their families, cases of IID ascertained from a population cohort component and those presenting to general practices were sent a socio-economic questionnaire 3 weeks after the acute episode. The impact of the illness was measured and the resources used were identified and costed. The duration, severity and costs of illness linked to viruses were less than those linked to bacteria. The average cost per case of IID presenting to the GP was Pound Sterling253 and the costs of those not seeing a GP were Pound Sterling34. The average cost per case was Pound Sterling606 for a case with salmonella, Pound Sterling315 for campylobacter, Pound Sterling164 for rotavirus and Pound Sterling176 for SRSV. The estimated cost of IID in England was Pound Sterling743m expressed in 1994/5 prices. The costs of IID are considerable and the duration of the illness was found to be longer than previous reports have suggested.

Measles trends and vaccine effectiveness in Nairobi, Kenya.

OBJECTIVES: To determine morbidity and mortality from measles and to estimate measles vaccine effectiveness among children hospitalised with measles in two hospitals in Nairobi. DESIGN: A review of hospital records (index cards). SETTING: Kenyatta National Hospital and Mbagathi District Hospitals covering the years 1996-2000. METHOD: A review of index cards for measles morbility and mortality was undertaken in the two hospitals. Measles data at the Kenya Expanded Programme on Immunisation covering both hospitals was analysed for vaccine effectiveness. RESULTS: The incidence of measles was unusually high in 1998 between July and November (monthly range 130-305), reflecting on the occurrence of an outbreak at that time. There was no definite monthly incidence trend of measles in 1996,1997, 1999 and 2000. The median age of cases was 13 months (range 0-420 months) for Kenyatta hospital and 18 months (range 1-336 months) for Mbagathi Hospital. Significantly, 29.8% of all cases were aged below nine months when routine immunisation for measles had not begun. The median number of days spent in hospital were five days (range 0-87 days) for Kenyatta and four days (range 1-13 days) for Mbagathi. The overall case fatality rate was 5.6% and was similar for both males and females. The overall measles vaccine effectiveness among measles cases admitted to Kenyatta and Mbagathi Hospitals was 84.1%. CONCLUSION: The case admissions in Kenyatta and Mbagathi Hospitals suggest measles was prevalent in Nairobi over the latter half decade of the 1990's. Apart from 1998 when there was an outbreak, the seasonality of measles was dampened. The 1998 outbreak suggests a build up of susceptible children the majority of whom were born in the last quarter of 1996. The high mortality may have had to do with the majority of cases presenting late when symptoms were already complicated and severe.

The study of infectious intestinal disease in England: risk factors for cases of infectious intestinal disease with Campylobacter jejuni infection.

This is a case-control study aimed at identifying risk factors for intestinal infection with Campylobacter jejuni. Cases were defined as subjects with diarrhoea occurring in community cohorts or presenting to General Practitioners (GPs) with Campylobacter jejuni in stools. Controls were selected from GP lists or cohorts, matched by age, sex, and GP practice. Travel abroad and consumption of chicken in a restaurant were statistically significantly associated with being a case. There was no statistically significant risk associated with consumption of chicken other than in restaurants nor with reported domestic kitchen hygiene practices. Consumption of some foods was associated with a lower risk of being a case. Most cases remained unexplained. We suggest that infection with low numbers of micro-organisms, and individual susceptibility may play a greater role in the causation of campylobacter infection than previously thought. It is possible that in mild, sporadic cases infection may result from cross contamination from kitchen hygiene practices usually regarded as acceptable. Chicken may be a less important vehicle of infection for sporadic cases than for outbreaks, although its role as a source of infection in both settings requires further clarification in particular in relation to the effect of domestic hygiene practices. The potential effect of diet in reducing the risk of campylobacteriosis requires exploration.

A study of infectious intestinal disease in England: risk factors associated with group A rotavirus in children.

OBJECTIVE: To identify risk factors for infectious intestinal disease (IID) due to rotavirus group A in children aged under 16 years. METHODS: Case-control study of cases of IID with rotavirus infection presenting to general practitioners (GPs) or occurring in community cohorts, and matched controls. RESULTS: There were 139 matched pairs. In children under 16 years the following risk factors were significantly associated with rotavirus IID: living in rented council housing (adjusted OR = 3.78, P = 0.022), accommodation with more than five rooms (OR = 0.72, P = 0.002), contact with someone ill with IID (OR = 3.45, P < 0.001). Some foods were associated with decreased risk. In infants, bottle feeding with or without breast feeding was associated with increased risk (OR = 9.06, P < 0.05). CONCLUSIONS: Contact with persons with IID, living in rented council housing and accommodation with fewer rooms, were significant risk factors for sporadic rotavirus IID in children whereas breast feeding is protective in infants.

Persistence of anti-leptospiral IgM, IgG and agglutinating antibodies in patients presenting with acute febrile illness in Barbados 1979-1989.

The persistence of anti-leptospiral IgM and IgG antibodies and agglutinating antibodies was studied in serologically confirmed cases of severe leptospirosis during the acute illness and over periods of several years after recovery. The antibody response in non-leptospirosis patients presenting to hospital with similar symptoms over the same period of time was used to estimate the background antibody level to leptospirosis in the community. All patients enrolled in the study had blood samples collected twice in the acute stage of illness, once during convalescence and then annually from the time of initial hospitalisation until the end of the study period. Six hundred and thirty-eight patients presented to hospital with acute febrile illness, of whom 321 were diagnosed with leptospirosis. Patients who had severe leptospirosis commonly remained seropositive, with IgM, IgG and agglutinating antibodies detectable for several years after infection. A significant proportion of cases had high titres of agglutinating antibody detectable by the microscopic agglutination test (> or = 800). There were marked differences in the magnitude and duration of persistence of agglutinating antibodies directed against different serogroups. More than 20% of cases with evidence of infection with serogroup Autumnalis retained titres of >800, 4 years after the acute illness. In one case a titre of 800 was detected 11 years after infection. Persistence of agglutinating antibody titres can create problems in interpretation of serological results and make it impossible to estimate the time of infection, given a specific titre. This study demonstrates that in endemic areas where seroprevalence is high, use of a single elevated titre is not reliable to define a current infection.

Assessment of the efficacy of an IgM-elisa and microscopic agglutination test (MAT) in the diagnosis of acute leptospirosis.

In a prospective study in Barbados between 1979 and 1989, 321 cases were diagnosed in 638 patients presenting at a hospital with symptoms of leptospirosis. Initial diagnosis was based on patient history and characteristic signs and symptoms. In 92 cases (29%), diagnosis was confirmed by isolation of organisms from the blood, urine, or dialysate fluid; in the remaining 229 cases (71%) diagnosis was confirmed by serology alone. Results of an IgM-ELISA and microscopic agglutination test (MAT) in cases with isolates and in non-leptospirosis cases were used to assess the sensitivity and specificity of the tests. The sensitivity of IgM detection by ELISA was 52% in the first acute-phase specimen, increasing to 89% and 93% in the second acute-phase and convalescent specimens, respectively. The specificity of the IgM-ELISA was high (> or = 94%) in all specimens. The sensitivity of the MAT was low (30%) in the first acute-phase specimen, increasing to 63% in the second acute-phase specimen and 76% in the convalescent specimen. The specificity of the MAT was > or = 97% in all specimens.