Amelia: a multi-center descriptive epidemiologic study in a large dataset from the International Clearinghouse for Birth Defects Surveillance and Research, and overview of the literature

Limb-body wall complex: Literature review and case report

INTRODUCTION

Body wall anomalies comprise a wide range of malformations. Limb-Body wall complex (LBWC) represents the most severe presentation of this group, with life threatening malformations in practically all the cases, including craniofacial, body wall defects, and limb anomalies. There is no consensus about its etiology and folding and gastrulation defects have been involved. Also, impaired angiogenesis has been proposed as a causative process.

CASE REPORT

We present the case of a masculine stillborn, product of the first pregnancy in a 15-year-old, apparently healthy mother. He was delivered at 31 weeks of gestation due to an early rupture of membranes. He presented with multiple malformations including a wide body wall defect with multiple organ herniation and meromelia of the lower right limb.

DISCUSSION AND CONCLUSIONS

LBWC represents a severe and invariably fatal pathology. There are no described risk factors, nevertheless, this case presented in a teenage mother, a well-described risk factor for other body wall anomalies. Its diagnosis allows us to discriminate between other pathologies that require prenatal or postnatal specialized treatment.

Total Hip Arthroplasty in Patients with Bilateral Upper-Limb Amelia: A Report of 2 Cases

CASE

We report two patients, a 43-year-old man and a 26-year-old woman, with bilateral absence of the upper extremity and severe hip osteoarthritis. The involved hip was the dominant extremity for both patients. Total hip arthroplasty (THA) was performed using a posterior approach with dual-mobility implants. Both patients report satisfactory outcomes including the ability to perform the significant range of motion required for daily activities such as toe-to-head motion.

CONCLUSION

In patients with extreme range of motion requirements such as those affected with bilateral upper-limb amelia, a posterior THA with a dual-mobility implant may be safely and successfully performed to treat disabling hip osteoarthritis.

Helping to shine light on the Dark Ages: Applying the bioarchaeology of care approach to remains from the early Anglo-Saxon cemetery at Worthy Park

OBJECTIVE

To test the hypothesis that a bioarchaeological focus on health-related care provision can contribute to the currently limited understanding of social practice in Early Anglo-Saxon England (mid5th-early7th centuries AD).

MATERIALS

Published descriptions of pathology in 69 adult remains from the Early Anglo-Saxon cemetery of Worthy Park, southern England.

METHODS

Three case studies (one examining likely need for care at an individual level and two at a population level) were undertaken using the bioarchaeology of care approach.

RESULTS

Analyses indicate likely care provision ('direct support' and/or 'accommodation of difference') to Worthy Park individuals experiencing temporary or permanent disability. Interpretation suggests community interdependence, cooperation, flexibility and tolerance of difference, as well as cultural and socioeconomic mechanisms for managing physical and social challenges of ageing.

CONCLUSIONS

This study provides proof of concept that bioarchaeology of care analysis can offer new insights into social practice in this period.

SIGNIFICANCE

This study demonstrates that a bioarchaeological focus on caregiving behaviours in an Early Anglo-Saxon community extends modern thinking about social relations in post-Roman Britain, offering a model for future investigations into social practice in this, and potentially other, periods. More generally, it illustrates the richness of results achievable when combining bioarchaeological and historical research.

LIMITATIONS

Reliance on secondary sources limited detail (and potentially accuracy) of interpretation possible.

SUGGESTIONS FOR FURTHER RESEARCH

This study's approach should be further tested and refined, either through application to different Anglo-Saxon (or other historic) populations or in a more thorough analysis of the Worthy Park sample itself.

Amelia and phocomelia in Finland: Characteristics and prevalences in a nationwide population‐based study

BACKGROUND

Amelia and phocomelia represent severe limb reduction defects. Specific epidemiologic data on these defects are scarce. We conducted a descriptive analysis of prevalence data in Finland during 1993-2008 to clarify the epidemiology nationwide in a population-based register study. We hypothesized that increasing maternal age would affect the total prevalence of each disorder.

MATERIALS AND METHODS

We collected information on all fetuses and infants affected by amelia and phocomelia during 1993-2008 from the National Register of Congenital Malformations in Finland. The clinical, laboratory, autopsy, and imaging data were re-evaluated where available for all cases found.

RESULTS

A total of 23 amelia and 7 phocomelia patients were identified. Thalidomide was not an etiological factor in any of the cases. The total prevalence of amelia was 2.43 per 100,000 births. The live birth prevalence was 0.63 per 100,000 live births. The total prevalence of phocomelia was 0.74 per 100,000 births, and the live birth prevalence was 0.53 per 100,000 live births. Infant mortality in amelia and phocomelia was 67% and 60%, respectively.

CONCLUSIONS

Infant mortality is high among amelia and phocomelia. Most cases had other major associated anomalies, but syndromic amelia cases were rare. Total prevalences were higher than previously reported and showed an increase in prevalence toward the end of the study period. The percentage of elective terminations of pregnancy for these disorders is high. While isolated cases are rare, they most likely present a better prognosis. Thus, correct diagnosis is essential in counseling for possible elective termination.

Geotemporospatial and causal inference epidemiological analysis of US survey and overview of cannabis, cannabidiol and cannabinoid genotoxicity in relation to congenital anomalies 2001–2015

Background

Cannabinoids including cannabidiol have recognized genotoxic activities but their significance has not been studied broadly epidemiologically across the teratological spectrum. We examined these issues including contextual space-time relationships and formal causal inferential analysis in USA.

Methods

State congenital anomaly (CA) rate (CAR) data was taken from the annual reports of the National Birth Defects Prevention Network 2001–2005 to 2011–2015. Substance abuse rates were from the National Survey of Drug Use and Health a nationally representative longitudinal survey of the non-institutionalized US population with 74.1% response rate. Drugs examined were cigarettes, monthly and binge alcohol, monthly cannabis and analgesic and cocaine abuse. Early termination of pregnancy for abortion (ETOPFA) rates were taken from the published literature. Cannabinoid concentrations were from Drug Enforcement Agency. Ethnicity and income data were from the US Census Bureau. Inverse probability weighted (IPW) regressions and geotemporospatial regressions conducted for selected CAs.

Results

Data on 18,328,529 births from an aggregated population of 2,377,483,589 for mid-year analyses 2005–2013 comprehending 12,611 CARs for 62 CAs was assembled and ETOPFA-corrected (ETOPFACAR) where appropriate. E-Values for ETOPFACARs by substance trends were elevated for THC (40 CAs), cannabis (35 CAs), tobacco (11 CAs), cannabidiol (8 CAs), monthly alcohol (5 CAs) and binge alcohol (2 CAs) with minimum E-Values descending from 16.55, 1.55x107, 555.10, 7.53x1019, 9.30 and 32.98. Cardiovascular, gastrointestinal, chromosomal, limb reductions, urinary, face and body wall CAs particularly affected. Highest v. lowest substance use quintile CAR prevalence ratios 2.84 (95%C.I. 2.44, 3.31), 4.85 (4.08, 5.77) and 1.92 (1.63, 2.27) and attributable fraction in exposed 0.28 (0.27, 0.28), 0.57 (0.51, 0.62) and 0.47 (0.38, 0.55) for tobacco, cannabis and cannabidiol. Small intestinal stenosis or atresia and obstructive genitourinary defect were studied in detail in lagged IPW pseudo-randomized causal regressions and spatiotemporal models confirmed the causal role of cannabinoids. Spatiotemporal predictive modelling demonstrated strongly sigmoidal non-linear cannabidiol dose-response power-function relationships (P = 2.83x10−60 and 1.61x10−71 respectively).

Conclusions

Data implicate cannabinoids including cannabidiol in a diverse spectrum of heritable CAs. Sigmoidal non-linear dose-response relationships are of grave concern.

These transgenerational genotoxic, epigenotoxic, chromosomal-toxic putatively causal teratogenic effects strongly indicate tight restrictions on community cannabinoid penetration.

Effects of cannabis on congenital limb anomalies in 14 European nations: A geospatiotemporal and causal inferential study

Cannabinoid exposure is increasing in some European nations. Europe therefore provides an interesting test environment for the recently reported link between cannabis exposure and congenital limb anomaly (CLA) rates (CLARs). Exponential genotoxic dose-response relationships make this investigation both intriguing and imperative. Annual CLAR in 14 nations were from Epidemiological Surveillance of Congenital Anomalies. Drug use rates were from European Monitoring Centre for Drugs and Drug Dependency. Median household income was from the World Bank. E-values provide a quantitative measure of robustness of results to confounding by extraneous covariates. Inverse probability weighting is an important technique for equalizing exposures across countries and removing sources of bias. Rates of CLA, hip dysplasia and the whole group of limb anomalies were higher in countries with increasing daily cannabis use (P = 1.81 × 10^-16, 0.0005 and 2.53 × 10^-6, respectively). In additive inverse-probability-weighted panel models, the limb reduction-resin Δ9-tetrahydrocannabinol (THC) concentration E-value estimate was 519.93 [95% lower bound (mEV) 49.56], order Resin > Herb ≫ Tobacco > Alcohol. Elevations were noted in 86% E-value estimates and 70.2% of mEVs from 57 E-value pairs from inverse-probability-weighted panel models and from spatial models. As judged by the mEV the degree of association with metrics of cannabis exposure was hip dysplasia > polydactyly > syndactyly > limb anomalies > limb reductions with median E-value estimates from 3.40 × 10⁶⁵ to 7.06 and median mEVs from 6.14 × 10³³ to 3.41. Daily cannabis use interpolated was a more powerful metric of cannabis exposure than herb or resin THC exposure. Data indicate that metrics of cannabis exposure are closely linked with CLAR and satisfy epidemiological criteria for causality. Along with Hawaii and the USA, Europe now forms the third international population in which this causal link has been demonstrated. Cannabis as a predictor of limb anomalies was more potent than tobacco or alcohol. Cannabinoid access should be restricted to protect public health and the community genome/epigenome transgenerationally.

Maternal Risk Factors Associated with Limb Reduction Defects: Data from the Polish Registry of Congenital Malformations (PRCM)

Data from the Polish Registry of Congenital Malformations (PRCM) suggest that the prevalence of limb reduction defects (LRDs) in some Polish regions is significantly higher in comparison to that reported in the European Surveillance of Congenital Anomalies (EUROCAT) registry, but specific risk factors are still unknown. The objectives of this study were two-fold: to detect risk factors linked to isolated LRDs among Polish natives and to search for geospatial clusters of isolated LRDs to identify high-risk areas across the country. Among the 2,939,001 births accounted for in the PRCM, we determined that there were 852 children with distinct LRDs. Our data demonstrate that lower birth weight, prematurity, and maternal smoking history are strongly associated with isolated LRDs. Furthermore, our investigation pointed to various additional risk factors for isolated LRDs, including paternal education, gestational hypertension, upper respiratory tract infections, and exposure to anti-inflammatory drugs in the first trimester of pregnancy. We did not recognize statistically significant spatial or spatiotemporal clusters over the area of Poland using Kulldorff’s scan. Our study strengthens the hypothesis that maternal factors have an integral role in the etiology of isolated LRDs.

[Prenatal Diagnostics and Postnatal Complications in a Case of Extremely Rare Tetra-Amelia]

Tetra-amelia is extremely rare with an incidence of 2.4 per 10,000,000 births. It describes the absence of all 4 outer extremities and can be associated with other malformations. The boy presented here was diagnosed at 22 1/7 weeks of gestation by sonography in 2D and 3D mode. The parents decided to continue the pregnancy; vaginal birth occurred after external rotation at 38 1/7 weeks of pregnancy. Postnatally, surgical closure of a cleft of the soft palate was performed. External abnormalities manifested themselves increasingly in the area of the spine and the face. The anatomically limited psychomotor development of the child is supported by physiotherapy, occupational therapy, and speech therapy. Various aids enable the child to participate in activities appropriate to his age.

Association of upper limb meromelia, proximal focal femoral deficiency, fibular hemimelia, and intermetatarsal coalition in a young adult male

Meromelia refers to the partial absence of at least 1 limb and is also referred to as "terminal transverse hemimelia." It can occur in either isolation or with other congenital malformations. There are very few publications in the literature that report meromelia cases accompanied by other congenital anomalies. Proximal focal femoral deficiency is another rare congenital skeletal abnormality and is characterized by the underdevelopment of the proximal part of the femur and shortening of the entire lower extremity. A case of upper limb meromelia accompanied by proximal focal femoral deficiency and fibular hemimelia in a neonate has previously been reported. However, to our knowledge, the association of upper limb meromelia with intermetatarsal coalition has never been reported to date. Here, we present an adult patient showing an unusual association of multiple rare congenital skeletal abnormalities including meromelia, proximal focal femoral deficiency, fibular hemimelia, and intermetatarsal coalition.

Functional outcomes in bilateral upper limb Amelia patient with scoliosis post vertical expandable prosthetic titanium rib (VEPTR) application: A case report

INTRODUCTION

Congenital upper limb Amelia is one of the extremely rare conditions in the world. Defined as complete absence of a limb which may present as isolated defect or as a part of syndrome with associated anomalies.

PRESENTATION OF THE CASE

We report a case of a medically free 6-year-old boy with bilateral upper limb Amelia associated with right thoracolumbar idiopathic Scoliosis.

DISCUSSION

Treatment for early onset scoliosis includes either posterior spinal fusion and instrumentation, or Vertical Expandable Prosthetic Titanium Rib (VEPTR). The choice of care for our patient was decided to be VEPTR alone as definitive management. Up to our knowledge, there are very scanty articles published regarding treatment for such cases.

CONCLUSION

Patient underwent vertical expandable prosthetic titanium rib (VEPTR) application for his large 45-degree curve as a definitive treatment and still have his preoperative physical functions, in terms of using lower limbs in daily living activities.

Managing a Pregnancy With Maternal Amelia

INTRODUCTION

Amelia, the complete absence of a limb, presents various management issues in pregnancy and delivery.

CASE

A woman with amelia of both lower limbs and flipper-like upper limb buds (phocomelia) presented in her first pregnancy at 19 weeks of gestation. Challenging issues encountered in the care of the patient included venous access, reliable blood pressure measurement, recommendations regarding mode of delivery, and preparation for caring for the child. The patient had abnormalities of the pelvis but an adequate midpelvis, so she was able to deliver vaginally without complication.

CONCLUSION

Careful planning to allow necessary modification of intrapartum management can allow for normal vaginal birth for a patient with severe limb reduction abnormalities such as amelia and phocomelia.

Upper Limb Meromelia with Oligodactyly and Brachymesophalangy of the Foot: An Unusual Association

Meromelia is a rare skeletal abnormality characterized by the partial absence of at least one limb. Several mechanisms have been postulated to explain the etiopathogenesis of the disorder. Most of the cases of meromelia are reported to be sporadic. It can occur either in isolation or with other congenital malformations. VACTERL association, gastroschisis, atrial septal defect, proximal femoral focal deficiency, and fibular hemimelia are the congenital abnormalities reported to be in association with meromelia. However, no other congenital abnormalities in association with meromelia have been recorded to date. We herein present an unusual case of bilateral upper limb meromelia accompanied by unilateral oligodactyly and brachymesophalangy of the foot.

[Reporting of birth defects from the Zika outbreak in Colombia, 2015-2017Notificação de defeitos congênitos associados ao surto de vírus zika na Colômbia, 2015-2017]

Objetivo.

El brote por virus del Zika afectó a varios países tropicales durante 2015 y 2016. Esto obligó a crear estrategias de vigilancia intensificada de microcefalia y otros síndromes neurológicos. Se evaluó el efecto del brote por virus del Zika en la notificación de defectos congénitos en Colombia desde la perspectiva del sistema nacional de vigilancia.

Métodos.

Se analizó la notificación nacional de recién nacidos con diferentes defectos congénitos y se determinaron las variaciones en la notificación atribuidas a la epidemia mediante un modelo semiparamétrico denominado “diferencia en diferencias” (DID).

Resultados.

Un total de 18 234 casos por defectos congénitos fueron notificados en Colombia durante el período de estudio. La mayoría eran malformaciones congénitas (91,9%). El 82,3% se confirmó por diagnóstico clínico o nexo epidemiológico. En el caso de la microcefalia, se notificaron ocho casos nuevos por semana epidemiológica (coeficiente de notificación de casos [D] = 8,8; P = 0,000) y 32 casos por otras malformaciones congénitas anatómicas (D = 32,0; P = 0,000). El valor absoluto del estimador de diferencia en diferencias atribuido al brote por virus del Zika incrementó la notificación semanal de casos de microcefalia (DID = |-5,0|; P = 0,008) y malformaciones congénitas (DID = |-12,0|; P = 0,111).

Conclusiones.

El brote por virus del Zika incrementó la notificación de recién nacidos con microcefalia, pero sin ninguna variación significativa en la notificación de otras malformaciones y defectos congénitos funcionales de origen sensorial o metabólico en el sistema de vigilancia.

Value of sharing and networking among birth defects surveillance programs: an ICBDSR perspective

Birth defects (BD), also known as congenital anomalies, are structural or functional abnormalities present at birth as a result of abnormal prenatal development. Their cause can be broadly categorized as genetic, environmental, or a combination of both. It is estimated that approximately 3-6% of newborn infants worldwide are affected by BD, many of which are associated with serious morbidity, mortality, and lifelong disabilities. The International Clearinghouse for Birth Defects Surveillance and Research (ICBDSR), founded in 1974, promotes worldwide birth defect surveillance, research, and prevention through the ongoing sharing of data, expertise, and training. In this review, we show value and contribution of BD surveillance systems in pursuing these aims. In the time of personalized medicine for many rare and common diseases, there are still massive gaps in our understanding of the causes and mechanisms of many birth defects, especially structural congenital anomalies. The main aim of the Sustainable Development Goals (SDGs), adopted by the United Nations in 2015, is to ensure healthy lives and promote well-being for all children. One specific goal is to end preventable deaths of newborns and children less than 5 years of age by 2030. The SDGs also underscore the need to consider BD as a priority in the global child health agenda. It can be said that counting BD helps BD to count. By sharing data and expertise and joining in surveillance and research, BD surveillance programs can play a major role in increasing our understanding of the causes of BD, and promoting prevention.

Analytic Methods for Evaluating Patterns of Multiple Congenital Anomalies in Birth Defect Registries

BACKGROUND

It is estimated that 20 to 30% of infants with birth defects have two or more birth defects. Among these infants with multiple congenital anomalies (MCA), co-occurring anomalies may represent either chance (i.e., unrelated etiologies) or pathogenically associated patterns of anomalies. While some MCA patterns have been recognized and described (e.g., known syndromes), others have not been identified or characterized. Elucidating these patterns may result in a better understanding of the etiologies of these MCAs.

METHODS

This article reviews the literature with regard to analytic methods that have been used to evaluate patterns of MCAs, in particular those using birth defect registry data.

RESULTS

A popular method for MCA assessment involves a comparison of the observed to expected ratio for a given combination of MCAs, or one of several modified versions of this comparison. Other methods include use of numerical taxonomy or other clustering techniques, multiple regression analysis, and log-linear analysis. Advantages and disadvantages of these approaches, as well as specific applications, were outlined.

CONCLUSION

Despite the availability of multiple analytic approaches, relatively few MCA combinations have been assessed. The availability of large birth defects registries and computing resources that allow for automated, big data strategies for prioritizing MCA patterns may provide for new avenues for better understanding co-occurrence of birth defects. Thus, the selection of an analytic approach may depend on several considerations. Birth Defects Research 110:5-11, 2018. © 2017 Wiley Periodicals, Inc.

Metacarpal Bone Plane Examination by Ultrasonography for the Diagnosis of Fetal Forearm and Hand Deformity

We explored the value of the metacarpal bone plane in screening for serious fetal forearm and hand deformities, excluding simple polydactyly and dactylion deformity, by ultrasonographic examination. Observed the second to fifth metacarpal bone plane of fetuses in 20,139 pregnant women at a gestational age of 16 to 30 weeks in The International Peace Maternity & Child Health Hospital of China Welfare Institute (IPMCH). There was a total 138 cases of fetal forearm and/or hand deformity among the 20,139 pregnant women. Of these, 134 cases were diagnosed, 4 cases were not diagnosed, and 1 case was misdiagnosed. Among the 134 diagnosed cases, there were 19 cases of hand absence, 5 cases of cleft hand, 13 cases of ectrodactyly, 26 cases of radius absence, 9 cases of forearm and hand dysplasia, 55 cases of thanatophoric dysplasia, 6 cases of wrist joint dysplasia, and 1 case of forearm amputation deformity. The deformity rate was 0.76%, the diagnostic coincidence rate was 99.97%, the sensitivity was 97.10%, the specificity was 99.99%, and the false negative rate was 2.9%. As such, careful observation of the metacarpal bone plane can be used increase the diagnosis rate of fetal forearm and hand deformity.

Reports to the Vaccine Adverse Event Reporting System after hepatitis A and hepatitis AB vaccines in pregnant women

OBJECTIVE

To characterize adverse events (AEs) after hepatitis A vaccines (Hep A) and hepatitis A and hepatitis B combination vaccine (Hep AB) in pregnant women reported to the Vaccine Adverse Event Reporting System (VAERS), a spontaneous reporting surveillance system.

STUDY DESIGN

We searched VAERS for AEs reports in pregnant women who received Hep A or Hep AB from Jan. 1, 1996-April 5, 2013. Clinicians reviewed all reports and available medical records.

RESULTS

VAERS received 139 reports of AEs in pregnant women; 7 (5.0%) were serious; no maternal or infant deaths were identified. Sixty-five (46.8%) did not describe any AEs. For those women whose gestational age was available, most were vaccinated during the first trimester, 50/60 (83.3%) for Hep A and 18/21 (85.7%) for Hep AB. The most common pregnancy-specific outcomes following Hep A or Hep AB vaccinations were spontaneous abortion in 15 (10.8%) reports, elective termination in 10 (7.2%), and preterm delivery in 7 (5.0%) reports. The most common nonpregnancy specific outcome was urinary tract infection and nausea/vomiting with 3 (2.2%) reports each. One case of amelia of the lower extremities was reported in an infant following maternal Hep A immunization.

CONCLUSION

This review of VAERS reports did not identify any concerning pattern of AEs in pregnant women or their infants following maternal Hep A or Hep AB immunizations during pregnancy.

Amelia-meromelia sequence with atrial septal defect-a rare occurrence

Amelia and Meromelia may either present as an isolated defect or associated with other malformations; and the diagnosis is mainly clinical. The antenatal period of the case presented here was medically unsupervised but uneventful. The baby had bilateral upper limb Meromelia and bilateral lower limb Amelia along with a small ostium secundum atrial septal defect. Except for the young age of mother, there was no other obvious risk factor in this case. The baby had a normal and healthy neonatal outcome whereas most such cases are either stillborn or end in early neonatal death.

Big data and clinicians: a review on the state of the science

BACKGROUND

In the past few decades, medically related data collection saw a huge increase, referred to as big data. These huge datasets bring challenges in storage, processing, and analysis. In clinical medicine, big data is expected to play an important role in identifying causality of patient symptoms, in predicting hazards of disease incidence or reoccurrence, and in improving primary-care quality.

OBJECTIVE

The objective of this review was to provide an overview of the features of clinical big data, describe a few commonly employed computational algorithms, statistical methods, and software toolkits for data manipulation and analysis, and discuss the challenges and limitations in this realm.

METHODS

We conducted a literature review to identify studies on big data in medicine, especially clinical medicine. We used different combinations of keywords to search PubMed, Science Direct, Web of Knowledge, and Google Scholar for literature of interest from the past 10 years.

RESULTS

This paper reviewed studies that analyzed clinical big data and discussed issues related to storage and analysis of this type of data.

CONCLUSIONS

Big data is becoming a common feature of biological and clinical studies. Researchers who use clinical big data face multiple challenges, and the data itself has limitations. It is imperative that methodologies for data analysis keep pace with our ability to collect and store data.

Birth prevalence for congenital limb defects in the northern Netherlands: a 30-year population-based study

Background

Reported birth prevalences of congenital limb defects (CLD) vary between countries: from 13/10,000 in Finland for the period 1964–1977 to 30.4/10,000 births in Scotland from 1964–1968. Epidemiological studies permit the timely detection of trends in CLD and of associations with other birth defects. The aim of this study is to describe the birth prevalence of CLD in the northern Netherlands.

Methods

In a population-based, epidemiological study we investigated the birth prevalences of CLD for 1981–2010. Data were collected by the European Surveillance of Congenital Anomalies in the northern Netherlands (EUROCAT-NNL). We excluded malpositions, club foot, and dislocation/dysplasia of hips or knees. Trends were analysed for the 19-year period 1992–2010 using χ² tests, as well as CLD association with anomalies affecting other organs.

Results

The birth prevalence of CLD was 21.1/10,000 births for 1981–2010. There was an overall decrease in non-syndromic limb defects (P = 0.023) caused by a decrease in the prevalence of non-syndromic syndactyly (P < 0.01) in 1992–2010. Of 1,048 children with CLD, 55% were males, 57% had isolated defects, 13% had multiple congenital anomalies (MCA), and 30% had a recognised syndrome. The upper:lower limb ratio was 2:1, and the left:right side ratio was 1.2:1. Cardiovascular and urinary tract anomalies were common in combination with CLD (37% and 25% of cases with MCA). Digestive-tract anomalies were significantly associated with CLD (P = 0.016).

Conclusions

The birth prevalence of CLD in the northern Netherlands was 21.1/10,000 births. The birth prevalence of non-syndromic syndactyly dropped from 5.2/10,000 to 1.1/10,000 in 1992–2010.

Prevalence of orofacial clefts in Nigeria

Orofacial clefts are the most common malformations of the head and neck. In Africa, orofacial clefts are underascertained, with little or no surveillance system in most parts for clefts and other birth defects. A Nigerian craniofacial anomalies study, NigeriaCRAN, was established in 2006 to support cleft research specifically for epidemiological studies, treatment outcomes, and studies into etiology and prevention. We pooled data from seven of the largest Smile Train treatment centers in the six geopolitical zones in Nigeria. Data from September 2006 to June 2011 were analyzed and clefts compared between sides and genders using the Fisher exact test. A total of 2197 cases were identified during the study period, with an estimated prevalence rate of 0.5 per 1000. Of the total number of orofacial clefts, 54.4% occur in males and 45.6% in females. There was a significant difference (P = .0001) between unilateral left clefts and unilateral right clefts, and there was a significant difference (P = .0001) between bilateral clefts and clefts on either the left or right side. A significant gender difference (P = .03) was also observed for cleft palate, with more females than males. A total of 103 (4.7%) associated anomalies were identified. There were nine syndromic cleft cases, and 10.4% of the total number of individuals with clefts have an affected relative. The significant difference between unilateral clefts and the gender differences in the proportion of cleft palate only are consistent with the literature. The present study emphasizes the need for birth defects registries in developing countries in order to estimate the exact prevalence of birth defects including orofacial clefts.

Phocomelia: a worldwide descriptive epidemiologic study in a large series of cases from the International Clearinghouse for Birth Defects Surveillance and Research, and overview of the literature

Epidemiologic data on phocomelia are scarce. This study presents an epidemiologic analysis of the largest series of phocomelia cases known to date. Data were provided by 19 birth defect surveillance programs, all members of the International Clearinghouse for Birth Defects Surveillance and Research. Depending on the program, data corresponded to a period from 1968 through 2006. A total of 22,740,933 live births, stillbirths and, for some programs, elective terminations of pregnancy for fetal anomaly (ETOPFA) were monitored. After a detailed review of clinical data, only true phocomelia cases were included. Descriptive data are presented and additional analyses compared isolated cases with those with multiple congenital anomalies (MCA), excluding syndromes. We also briefly compared congenital anomalies associated with nonsyndromic phocomelia with those presented with amelia, another rare severe congenital limb defect. A total of 141 phocomelia cases registered gave an overall total prevalence of 0.62 per 100,000 births (95% confidence interval: 0.52-0.73). Three programs (Australia Victoria, South America ECLAMC, Italy North East) had significantly different prevalence estimates. Most cases (53.2%) had isolated phocomelia, while 9.9% had syndromes. Most nonsyndromic cases were monomelic (55.9%), with an excess of left (64.9%) and upper limb (64.9%) involvement. Most nonsyndromic cases (66.9%) were live births; most isolated cases (57.9%) weighed more than 2,499 g; most MCA (60.7%) weighed less than 2,500 g, and were more likely stillbirths (30.8%) or ETOPFA (15.4%) than isolated cases. The most common associated defects were musculoskeletal, cardiac, and intestinal. Epidemiological differences between phocomelia and amelia highlighted possible differences in their causes.