Cost Effectiveness of Using Array-CGH for Diagnosing Learning Disability.

OBJECTIVE: To undertake a cost-effectiveness analysis of using microarray comparative genomic hybridisation (array-CGH) as a first-line test versus as a second-line test for the diagnosis of causal chromosomal abnormalities in patients referred to a NHS clinical genetics service in the U.K. with idiopathic learning disability, developmental delay and/or congenital anomalies. METHODS: A cost-effectiveness study was conducted. The perspective is that of a U.K. NHS clinical genetics service provider (with respect to both costs and outcomes). A cohort of patients (n = 1590) referred for array-CGH testing of undiagnosed learning disability and developmental delay by a single NHS regional clinical genetics service (South East Thames Regional Genetics Service), were split into a before-and-after design where 742 patients had array-CGH as a second-line test (before group-comparator intervention) and 848 patients had array-CGH as a first-line test (after group-evaluated intervention). The mean costs were calculated from the clinical genetics testing pathway constructed for each patient including the costs of genetic testing undertaken and clinical appointments scheduled. The outcome was the number of diagnoses each intervention produced so that a mean cost-per-diagnosis could be calculated. The cost effectiveness of the two interventions was calculated as an incremental cost-effectiveness ratio to produce an incremental cost-per-diagnosis (in 2013 GBP). Sensitivity analyses were conducted by altering both costs and effects to check the validity of the outcome. RESULTS: The incremental mean cost of testing patients using the first-line testing strategy was -GBP241.56 (95% CIs -GBP256.93 to -GBP226.19) and the incremental mean gain in the percentage diagnoses was 0.39% (95% CIs -2.73 to 3.51%), which equates to an additional 1 diagnosis per 256 patients tested. This cost-effectiveness study comparing these two strategies estimates that array-CGH first-line testing dominates second-line testing because it was both less costly and as effective. The sensitivity analyses conducted (adjusting both costs and effects) supported the dominance of the first-line testing strategy (i.e. lower cost and as effective). CONCLUSIONS: The first-line testing strategy was estimated to dominate the second-line testing strategy because it was both less costly and as effective. These findings are relevant to the wider UK NHS clinical genetics service, with two key strengths of this study being the appropriateness of the comparator interventions and the direct applicability of the patient cohort within this study and the wider UK patient population.

Dopamine agonists in the treatment of prolactinoma: are they still first choice?

Dopamine agonist therapy has been the cornerstone treatment for prolactinoma since the 1970s, replacing surgery in the primary management of this condition. These agents are effective in the management of prolactin excess, have a low side-effect profile, and in some cases may even be curative. However, recent studies of high dose dopamine agonists used in Parkinson's disease have raised the possibility that these drugs may be associated with cardiac valvulopathy. This paper discusses the modern use of dopamine agonists in a patient with prolactinoma.

Is karyotyping couples experiencing recurrent miscarriage worth the cost?

Karyotyping couples that have had recurrent miscarriages detects balanced rearrangements in carrier parents who can be offered prenatal cytogenetic analysis to prevent the birth of a subsequent child with an unbalanced rearrangement. In four UK centres, over periods of 5-30 years, balanced rearrangements were found in 406 out of 20,432 parents that had experienced miscarriage (1.9%), but only four unbalanced rearrangements were found after referral for prenatal diagnosis because of a balanced parental translocation ascertained for recurrent miscarriages. At an estimated cost of 3-4 million pounds, these data raise doubts about the cost effectiveness of current policies on the routine karyotyping of couples experiencing repeated miscarriages.

PEComa of the Upper Extremity: A Unique Case and Description of an Initial Response to Neoadjuvant Chemotherapy.

Purpose. Tumors of the perivascular epithelial cell tumor (PEComa), first described in 1992, represent a rare soft tissue neoplasm of varying malignant potential. Cases of PEComa have been previously described in a few somatic and visceral sites, most notably in the gastrointestinal tract, genitourinary tract, and one extremity case in the thigh. To date, most malignant cases of PEComa have been resistant to chemotherapy, and as such, an appropriate therapy is not known. Case report. Here we describe the first case of PEComa of the upper extremity. Open biopsy revealed a high-grade malignant lesion, and the patient subsequently underwent both neoadjuvant therapy with doxorubicin, ifosfamide and mensa, and radiation therapy prior to wide surgical resection. After six cycles of chemotherapy, the tumor underwent an 80% reduction in size. Subsequent neoadjuvant radiation therapy of 5000 cGy did not further reduce the size of the tumor. Following limb sparing radical resection, pathology showed 20% necrosis within a high-grade malignant lesion. Twenty one months after beginning treatment, the patient shows no sign of local recurrence, but metastatic disease was confirmed after resection of a lung nodule. Conclusion. Given the favorable albeit partial response seen in this patient, the course of therapy outlined here may represent a good starting point for neoadjuvant treatment in a tumor with a historically bleak prognosis. In addition, the diagnosis of PEComa must now be entertained in the differential diagnosis of upper extremity soft tissue sarcoma.

Selective parathyroid venous sampling in patients with complicated hyperparathyroidism.

OBJECTIVE: The role of preoperative localisation of abnormal parathyroid glands remains controversial but is particularly relevant to the management of patients with recurrent or persistent hyperparathyroidism and familial syndromes. We report our experience of the use of selective parathyroid venous sampling (PVS) in the localisation of parathyroid disease in such patients. DESIGN: We report a retrospective 10-year experience (n = 27) of the use of PVS in complicated primary hyperparathyroidism and contrast the use of PVS with neck ultrasound, magnetic resonance imaging (MRI), computed tomography (CT) and sestamibi imaging modalities. RESULTS: In 14 out of 25 patients who underwent surgery PVS results were completely concordant with surgical and histological findings and 88% of patients achieved post-operative cure. Out of 13 patients referred after previous failed surgery, 12 underwent further surgery which was curative in 9. In total PVS yielded useful positive (n = 13) and/or negative information (n = 6) in 19 out of 25 patients undergoing surgery. Using histology as the gold standard, 59% of PVS studies were entirely consistent with histology, as compared with 39% of ultrasound scans, 36% of sestamibi scans and 17% of MRI/CT scans. CONCLUSIONS: PVS is a valuable adjunct to MRI/CT and sestamibi scanning in selected patients with complicated hyperparathyroidism when performed in an experienced unit.

Robertsonian translocations--reproductive risks and indications for preimplantation genetic diagnosis.

BACKGROUND: Robertsonian translocations carry reproductive risks that are dependent on the chromosomes involved and the sex of the carrier. We describe five couples that presented for preimplantation genetic diagnosis (PGD). METHODS: PGD was carried out using cleavage-stage (day 3) embryo biopsy, fluorescence in-situ hybridization (FISH) with locus-specific probes, and day 4 embryo transfer. RESULTS: Couple A (45,XX,der(14;21)(q10;q10)) had two previous pregnancies, one with translocation trisomy 21. A successful singleton pregnancy followed two cycles of PGD. Couple B (45,XX,der(13;14)(q10;q10)) had four miscarriages, two with translocation trisomy 14. One cycle of PGD resulted in triplets. Couple C (45,XX,der(13;14)(q10;q10)) had four years of infertility; two cycles were unsuccessful. Couple D (45,XY,der(13;14)(q10;q10)) presented with oligozoospermia. A singleton pregnancy followed two cycles of PGD. Couple E (45,XY,der(13;14)(q10;q10)) had a sperm count within the normal range and low levels of aneuploid spermatozoa. PGD was therefore not recommended. No evidence for a high incidence of embryos with chaotic or mosaic chromosome complements was found. CONCLUSIONS: For fertile couples, careful risk assessment and genetic counselling should precede consideration for PGD. Where translocation couples need assisted conception for subfertility, PGD is a valuable screen for imbalance, even when the risk of viable chromosome abnormality is low.

Successful pregnancy outcomes after preimplantation genetic diagnosis (PGD) for carriers of chromosome translocations.

Reciprocal translocations are found in about 1 in 500 people, whereas Robertsonian translocations occur with a prevalence of 1 in 1000. Balanced carriers of these rearrangements, although phenotypically normal, may present with infertility, recurrent miscarriage, or offspring with an abnormal phenotype after segregation of the translocation at meiosis. Once the translocation has been identified, prenatal diagnosis can be offered, followed by termination of pregnancies with chromosome imbalance. Couples who have suffered repeated miscarriage or those who have undergone termination of pregnancy as a result of the translocation carrier status of one partner are looking increasingly to preimplantation genetic diagnosis (PGD) as a way of achieving a normal pregnancy. Similarly, infertile couples in which one partner is a translocation carrier may request PGD to ensure transfer of normal embryos after in vitro fertilization. Translocation PGD has been applied successfully in several centres worldwide and should now be considered as a realistic treatment option for translocation carriers who do not wish to trust to luck for a successful natural outcome.

Development and implementation of a new rapid aneuploidy diagnostic service within the UK National Health Service and implications for the future of prenatal diagnosis.

BACKGROUND: Prenatal diagnosis for chromosome abnormality is routinely undertaken by full karyotype analysis of chromosomes from cultured cells; pregnant women must wait on average 13-14 days for their results. Autosomal trisomies, which account for around 80% of significant abnormalities, can be detected by quantitative fluorescence (QF) PCR. We report on the development and implementation of this technique as the first such routine service within a diagnostic department of the UK National Health Service (NHS). METHODS: We designed a "one-tube test" comprising four primer pairs for polymorphic tetranucleotide repeat sequences on chromosome 21, four primer pairs for sequences on chromosome 18, three primer pairs for sequences on chromosome 13, and one primer pair to identify the sex chromosomes. All prenatal samples received by our NHS diagnostic department between April, 2000, and April, 2001, were tested. After DNA extraction, PCR amplification was done and the products separated on a capillary-based genetic analyser; the results were interpreted with dedicated software. Follow-up karyotype analysis was done on all samples. FINDINGS: 1148 amniotic fluid samples, 188 chorionic villus samples, and 37 fetal tissue samples were tested; the amplification failure rate was zero with our current protocol. QF-PCR results were obtained and reported on 1314 (98%) of the prenatal samples; the remaining 22 (2%) were uninformative because of maternal-cell contamination. One case of mosaicism in a chorionic villus sample, and two cases indicating somatic expansion of a tetranucleotide repeat were found. No false positive or false negative results were obtained. The mean reporting time for the last 4 months of data collection was 1.25 working days. INTERPRETATION: QF-PCR aneuploidy testing is an efficient and accurate technique for the detection of autosomal trisomies in prenatal samples. Implementation of this service has led to the rapid diagnosis of abnormalities and early reassurance for women with normal results.

Velopharyngeal incompetence and chromosome 22q11 deletion.

Chromosome 22q11 deletion gives rise to various phenotypes, including cardiac malformations, velopharyngeal abnormalities, absent thymus, and neurological defects. We assessed, in a prospective study, chromosome 22q11 deletion in 50 of 144 patients with velopharyngeal incompetence in the absence of overt clefting. 18 (12.5% of the whole cohort and 36% of patients tested for the deletion) had the 22q11 deletion. This frequency differs from an estimated population prevalence of 0.025% and suggests a need for screening for the 22q11 deletion in these patients.

Cysticercosis of the triceps--an unusual pseudotumor: case report and review.

Cysticercosis is a disease caused by encysted larvae of the tapeworm Taenia solium. Most muscular disease presents with central nervous system involvement or multiple cysts or both. The authors report a 25-year-old woman with a rare single muscle cyst presenting as a tender hard triceps mass. Results of clinical examination and magnetic resonance imaging were indicative of a soft tissue tumor. Excision of the mass revealed purulence, and the histologic diagnosis was cysticercosis. In the differential diagnosis of isolated muscular masses, a rare isolated cysticercus presenting as a pseudotumor should be considered.

A pregnancy following PGD for X-linked dominant [correction of X-linked autosomal dominant] incontinentia pigmenti (Bloch-Sulzberger syndrome): case report.

Incontinentia Pigmenti (Bloch-Sulzberger syndrome) is a rare multisystem, ectodermal disorder associated with dermatological, dental and ocular features, and in <10% of cases, severe neurological deficit. Pedigree review suggests X-linked dominance with lethality in affected males. Presentation in female carriers is variable. Following genetic counselling, a mildly affected female carrier diagnosed in infancy with a de novo mutation was referred for preimplantation sexing, unusually selecting for male gender, with an acceptance of either normality or early miscarriage in an affected male. Following standard in-vitro fertilization and embryo biopsy, fluorescence in situ hybridization (FISH) unambiguously identified two male and two female embryos. A single 8-cell, grade 4 male embryo was replaced. A positive pregnancy test was reported 2 weeks after embryo transfer, although ultrasonography failed to demonstrate a viable pregnancy. Post abortive fetal tissue karyotyping diagnosed a male fetus with trisomy 16. This is an unusual report of preimplantation genetic diagnosis (PGD) being used for selection of males in an X-linked autosomal dominant disorder and demonstrates the value of PGD where amniocentesis or chorion villus sampling followed by abortion is not acceptable to the patient. This case also demonstrates the importance of follow-up prenatal diagnosis.

Lack of cell cycle checkpoints in human cleavage stage embryos revealed by a clonal pattern of chromosomal mosaicism analysed by sequential multicolour FISH.

Multicolour fluorescence in situ hybridisation (FISH) analysis of interphase nuclei in cleavage stage human embryos has highlighted a high incidence of postzygotic chromosomal mosaicism, including both aneuploid and ploidy mosaicism. Indeed, some embryos appear to have a chaotic chromosomal complement in a majority of nuclei, suggesting that cell cycle checkpoints may not operate in early cleavage. Most of these studies, however, have only analysed a limited number of chromosomes (3-5), making it difficult to distinguish FISH artefacts from true aneuploidy. We now report analysis of 11 chromosomes in five sequential hybridisations with standard combinations of two or three probes and minimal loss of hybridisation efficiency. Analysis of a series of arrested human embryos revealed a generally consistent pattern of hybridisation on which was superimposed frequent deletion of one or both chromosomes of a specific pair in two or more nuclei indicating a clonal origin and continued cleavage following chromosome loss. With a binucleate cell in a predominantly triploid XXX embryo, the two nuclei remained attached during preparation and the chaotic diploid/triphoid status of every chromosome analysed was the same for each nucleus. Furthermore, in each hybridisation the signals were distributed as a mirror-image about the plane of attachment, indicating premature decondensation during anaphase consistent with a lack of checkpoint control.

Necrotizing soft-tissue infections.

Necrotizing fasciitis is a rare and often fatal soft-tissue infection involving the superficial fascial layers of the extremities, abdomen, or perineum. Necrotizing fasciitis typically begins with trauma; however, the inciting event may be as seemingly innocuous as a simple contusion, minor burn, or insect bite. Differentiating necrotizing infections from common soft-tissue infections, such as cellulitis and impetigo, is both challenging and critically important. A high degree of suspicion may be the most important aid in early diagnosis. Prompt diagnosis is imperative because necrotizing infections typically spread rapidly and can result in multiple-organ failure, adult respiratory distress syndrome, and death. Although group A Streptococcus is the most common bacterial isolate, a polymicrobial infection with a variety of Gram-positive, Gram-negative, aerobic, and anaerobic bacteria is more common. Orthopaedic surgeons are often the first physicians to evaluate patients with such infections and therefore need to be familiar with this potentially devastating disease and its management. Prompt diagnosis, immediate administration of broad-spectrum antibiotic coverage, and emergent aggressive surgical debridement of all compromised tissues are critical to reduce the morbidity and mortality of these rapidly progressing infections.

Detection of submicroscopic subtelomeric chromosome translocations: a new case study.

Two sisters presented with multiple congenital abnormalities and developmental delay; abnormalities elsewhere in their extended family suggested that their father carried a balanced translocation. G-banded chromosome analysis showed apparently normal karyotypes. Fluorescence in situ hybridisation (FISH) with whole chromosome paints revealed no apparent abnormality in the father. However, further FISH studies, using multiple subtelomeric probes, demonstrated a derivative chromosome 16 in one sister. Subsequent studies showed that her sister also had a derivative 16 which had been inherited in an unbalanced form from their father, who carried a balanced reciprocal translocation between chromosomes 1 and 16. This report describes the detection of this submicroscopic translocation and the clinical findings in the two sisters.

Characterization of a chromosomally complex lung cancer cell line using multiwell fluorescence in situ hybridization.

The chromosomal characterization of a non-small cell lung cancer cell line (NCIH358) is described. This characterization was achieved using a simple, cheap and technically straightforward multiwell fluorescence in situ hybridization (FISH) method. The many and complex chromosome rearrangements identified by this method could not be defined using conventional G-banded chromosome analysis, and have not been previously described. For the detailed characterization of complex cell lines, multiwell FISH has many advantages over more technically demanding and expensive FISH techniques, and opens up the possibility of screening for consistent rearrangements, leading to the identification of unique fusion genes.

Chromosome 22q11 deletions are not found in autistic patients identified using strict diagnostic criteria. IMGSAC. International Molecular Genetics Study of Autism Consortium.

A group of 103 subjects with a strict diagnosis of autism were tested for deletion of band q11.2 on the long arm of chromosome 22. No deletions were found, indicating that when a patient has been diagnosed with autism using strict and consistent criteria, in the absence of other indications, it is unlikely that this individual will have a 22q11 deletion. Testing for 22q11 deletions is therefore unlikely to be necessary in these patients. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 96:15-17, 2000.

Clinical expression of Menkes disease in a girl with X;13 translocation.

Menkes disease is a rare X-linked recessive disorder of copper metabolism, characterised by progressive neurological degeneration, abnormal hair and connective tissue manifestations. We report on a girl with classic Menkes disease, carrying a de novo balanced translocation 46,X,t(X;13)(q13.3; q14.3). The translocation breakpoints at Xq13.3 and 13q14.3 coincide with the Menkes disease and Wilson disease loci, respectively.

Screening oocytes and preimplantation embryos for aneuploidy.

Pregnancy and live birth rates following in-vitro fertilization decline rapidly with advancing maternal age partly because of an increase in age-related aneuploidies occurring in female meiosis. Screening oocytes or preimplantation embryos for common aneuploidies is now possible by polar body or cleavage stage biopsy and multicolour fluorescence in-situ hybridization.

Chromosomal mosaicism in cleavage-stage human embryos and the accuracy of single-cell genetic analysis.

PURPOSE: Our purpose was to assess the effect of chromosomal mosaicism in cleavage-stage human embryos on the accuracy of single-cell analysis for preimplantation genetic diagnosis. METHODS: Multicolor fluorescence in situ hybridization with X, Y, and 7 or X, Y, 7, and 18 chromosome-specific probes was used to detect aneuploidy in cleavage-stage human embryos. RESULTS: Most nuclei were diploid for the chromosomes tested but there was extensive mosaicism including monosomic, double-monosomic, nullisomic, chaotic, and haploid nuclei. CONCLUSIONS: Identification of sex by analysis of a single cleavage-stage nucleus is accurate but 7% of females are not identified. One or both parental chromosomes 7 were absent in at least 6.5% of the nuclei. With autosomal recessive conditions such as cystic fibrosis, carriers would be misdiagnosed as normal or affected. With autosomal dominant conditions, failure to analyze the affected parents allele (1.6-2.5%) would cause a serious misdiagnosis and analysis of at least two nuclei is necessary to reduce errors.