We can Diagnose it if we Consider it. Diagnostic Pitfall for Placenta: Placental Mesenchymal Dysplasia

Placental mesenchymal dysplasia is an increasingly recognizable abnormality. Early cases have been confused with partial hydatidiform mole. Placental mesenchymal dysplasia is probably under-diagnosed because of being an unfamiliar clinical entity and also mistaken for gestational trophoblastic disease due to the similar sonographic findings of two entities. In this report, we describe the clinical, gross, and histopathological findings of placental mesenchymal dysplasia in two cases. The 33-week-preterm baby of a 26-year-old woman with cardiovascular disease and 342 gram placenta and the 19-week fetus with trisomy 21 of a 40 year-old woman were terminated. Macroscopically thick-walled vessels and microscopically hydropic villous with peripherally localized thick-walled vessels without trophoblastic cell proliferation were observed in both cases. These two cases represent a rare placental anomaly that is benign but it is challenging to distinguish placental mesenchymal dysplasia from an incomplete mole. Placental mesenchymal dysplasia should be included in the differential diagnosis of sonographic findings that show a normal appearing fetus and a placenta with cystic lesions. Placental mesenchymal dysplasia is associated with pregnancy-related hypertension. In conclusion, the most important point is "you can diagnose it if you consider it".

A MOLECULARLY CHARACTERIZED INTERSTITIAL DELETION ENCOMPASSING THE 11q14.1-q23.3 REGION IN A CASE WITH MULTIPLE CONGENITAL ABNORMALITIES

Interstitial deletion of chromosome 11 long arm is a rare event. In most of the interstitial deletions on the long arm of chromosome 11 both the position and the size of these deletions are heterogeneous making a precise karyotype-phenotype correlation. In only a few of the reported cases has the deletion been molecularly characterized. Our patient was a 13-year-old male presented; mental motor retardation, strabismus, myopia, retinopathy, sensorineural hearing loss, a long and triangular face, a broad forehead, hypotelorism, nasal septal deviation, a beaked nose, hypoplastic ala nasie, bilateral low-set ears, a high arched palate, crowded teeth, retrognathia, thin lips, a long neck, and sloping shoulders, hyperactive behavior, pulmonary stenosis and lumbar scoliosis. Conventional cytogenetic analysis revealed 46,XY,del(11)(q14.1-q23.3) karyotype in the patient. Array-CGH analysis of the patient's DNA revealed an interstitial deletion encompassing 33.2 Mb in the 11q14.1-q23.3 genomic region (chr11: 83,161,443-116,401,751 ; Hg19). In this report, we present a patient with an interstitial deletion on the long arm of chromosome 11 that encompassed the 11q14.1-q23.3 region; and, using array-CGH analysis, we molecularly characterized the deleted region.

Chromosome abnormalities identified in 457 spontaneous abortions and their histopathological findings

OBJECTIVE

About 15% of clinically recognized pregnancies result in spontaneous abortion in the first trimester and the vast majority of these are the result of chromosome abnormalities. Studies of chromosomal constitutions of first trimester spontaneous abortions have revealed that at least 50% of the abortions have an abnormal karyotype. In this study we aimed to report the single centre experience of anomalies detected in spontaneous abortions.

MATERIAL AND METHOD

We present rare numerical and structural cytogenetic abnormalities detected in spontaneous abortion materials and the histopathological findings of rest material of abortion specimens in our study population.

RESULTS

Among 457 cases, 382 were successfully karyotyped while cell culture of 75 cases failed. Cytogenetic abnormalities were detected in 127 of 382 cases (33.24%). Autosomal trisomies were the predominant chromosomal abnormalities with a frequency of 48.8%. Structural chromosomal abnormalities were infrequent in conception materials. The mean age of the mothers was highest in trisomy group, the difference being significantly important (ANOVA p < 0.001). The most frequent chromosomal abnormalities were Turner syndrome, triploidy and trisomy of chromosome 16 followed by trisomy of chromosomes 22 and 21 and tetraploidy. Double trisomies and structural chromosomal abnormalities were rare. Trisomies were more frequent in advanced maternal age.

CONCLUSION

Detection of chromosomal abnormalities in spontaneous abortion materials is very important to clarify the causes of loss of pregnancy. Detection of structural chromosomal abnormalities in the cases and their carrier parents can provide proper genetic counseling to these families. These families can be directed towards pre-implantation genetic diagnosis to prevent further pregnancies with complications.

A familial interstitial 4q35 deletion with no discernible clinical effects

Small deletions on the long arm of distal chromosome 4 do not appear to result in gross congenital malformations, with the most frequently reported clinical findings including mild to moderate intellectual disability, learning disabilities and minor dysmorphic features. Here we report on a cytogenetically detectable familial interstitial chromosome 4 long arm deletion with no discernible phenotypic effects in a mother and her two daughters. The karyotypes of the mother and her two daughters were: 46,XX,del(4)(q35.1q35.2). Based on the results of FISH analyses using whole chromosome specific and subtelomeric probes, the karyotype was designated as: 46,XX,del(4)(q35.1q35.2). ish del(4)(q35-qter)(WCP4+, 36P21+, dJ963K6-). Array-CGH analysis showed an interstitial deletion encompassing 5.75 Mb in the 4q35.1-q35.2 genomic region (chr4:184,717,878-190,469,337; hg19). This is the first report on a cytogenetically detectable familial interstitial chromosome 4 long arm deletion in which there are no discernible phenotypic effects. Both our findings and a review of the literature suggest that more detailed molecular analyses are needed in cases with distal chromosome 4 long arm deletions especially those with breakpoints in the 4q35 region to establish a more precise genotype-phenotype correlation.

PRENATAL DIAGNOSIS OF DE NOVO PERICENTRIC INVERSION INV(2)(p11.2z13)

We here report a prenatal case with de novo pericentric inversion inv(2)(p11.2q13). A 20-years-old G1PO woman was referred for amniocentesis at 17 weeks of gestation, because of a positive second trimester screening test for aneuploidy. A de novo pericentric inversion inv(2)(p11.2q13) was detected during conventional cytogenetic analysis. Array-CGH analysis of the fetus showed no subtle chromosomal imbalances at the breakpoints. Genetic counseling was given to the family and the family decided to continue the pregnancy. To our knowledge, our case is the third prenatally detected de novo case with inv(2)(p11.2q13), and also the first case in which molecular karyotyping analysis were also applied.

PRENATAL DIAGNOSIS OF DE NOVO SUPERNUMERARY MARKER CHROMOSOME ORIGINATED FROM CHROMOSOME 16 BY ARRAY-CGH

A 33 years-old pregnant woman was referred for amniocentesis at 19 weeks of gestation due to abnormal serum biochemistry. A non-satellited, monocentric marker chromosome was observed with a frequency of 50% in cultured amniocytes. Parental karyotypes were normal. The marker chromosome was found to be derived from chromosome 16 by FISH and array-CGH analysis. Genetic counseling was given to parents and the family decided to terminate the pregnancy. Dysmorphic findings including; low set ears, exophtalmos depressed nasal bridge, large mouth and lips, posture anomalies at the extremities were detected at autopsy.

Rare structural chromosomal abnormalities in prenatal diagnosis; clinical and cytogenetic findings on 10125 prenatal cases

Objective: The aim of this study was presentation of the ultrasonographic findings and perinatal autopsy of cases with rare chromosomal abnormalities.

MATERIAL AND METHOD

A total of 10125 prenatal cases over 17 years including 8731 amniocentesis, 973 chorionic villus sampling, and 421 fetal blood sampling cases were evaluated for prenatal cytogenetic diagnosis. Conventional cytogenetic studies, fluorescence in situ hybridization studies, and Array-CGH analysis techniques were used for genetic analysis.

RESULTS

A structural chromosomal abnormality was observed in 95 cases. The most frequently observed structural abnormalities were balanced translocations with a frequency of 53.7% (51 cases) followed by unbalanced translocations (16.8%), inversions (11.6%), supernumerary marker chromosomes (8.4%), duplications (4.2%), deletions and ring chromosomes (2.1%) and complex translocation (1.1%). Rare structural chromosomal abnormalities including de novo balanced translocations, unbalanced translocations, inversions, duplications, deletions, ring chromosomes, and supernumerary marker chromosomes were detected in 24 cases.

CONCLUSION

The rate of rare chromosomal abnormalities varies from 2.4% (South East Ireland) to 12.9% (Northern England) in Europe with a total rate of 7.4/10 000 births. In our study, the overall rate of chromosomal abnormality in prenatal cytogenetic diagnosis was 3.7%, similar to South East Ireland. Ultrasonographic and perinatal autopsy findings of the cases with rare structural chromosomal abnormalities are important for proper genetic counseling for further similar cases.

Prenatal management, pregnancy and pediatric outcomes in fetuses with septated cystic hygroma

It has been reported that, compared with simple increased nuchal translucency, fetal cases with septated cystic hygroma (CH) are more likely to face perinatal handicaps. However, pediatric outcomes and proper prenatal counseling for this anomaly have not yet been truly defined. We performed this study to determine pregnancy and pediatric outcomes of fetuses with septated CH. We searched records for cases with septated CH and collected data for structural abnormalities, karyotype analysis, and pregnancy outcomes. Fetuses born with septated CH were also evaluated for their pediatric outcomes. Sixty-nine fetuses with septated CH were enrolled in the study. Results showed that chromosomal abnormalities were present in 28 fetuses (40.6%), and the most common aneuploidy was Turner syndrome (n=14, 20.3%); 16 (23.2%) of the remaining cases, in which aneuploidy was not found, had coexistent structural malformations; 25 (36.2%) cases had normal karyotype and morphology. The total number of live births and infants with unfavorable neurologic follow-up were 13 (18.8%) and 2 (2.9%), respectively. Septated CH is associated with poor perinatal outcomes; therefore, karyotype analysis and ultrasonographic anomaly screening should be performed as initial steps, and expectant management should be offered to couples with euploid fetuses that have normal morphology.

Prenatal diagnosis of isochromosome 21p and isochromosome 21q in a fetus with Down syndrome

The aim of this study was to present the first case with Down syndrome in conjunction with de novo isochromosomes of both short and long arm of the chromosome 21. Cytogenetics, molecular cytogenetics and molecular genetic analysis were performed on chorionic villus sampling at 12 weeks of gestation of a 42-years-old pregnant woman. According to cytogenetics, molecular cytogenetics and molecular genetic analysis the karyotype was designated as: 47,XY,i(21) (qter --> q10::q10 --> qter),+i(21) (pter --> p10::p10 --> 10pter).ish i(21)(qter --> q10::q10 --> qter)(CEP13/21+,WCP21+),+i(21) (pter --> p10::p10 --> pter)(CEP13/21+,WCP21+). Quantitative Fluorescent Polymerase Chain Reaction (QF-PCR) analysis revealed that isochromosome 21q was maternal in origin. After the detailed genetic counseling, the family decided termination of the pregnancy. This is the first report of co-existence of an isochromosome 21p and an isochromosome 21q in a case with Down syndrome. Our case shows the importance of the molecular cytogenetics and molecular genetic analysis in cases with isochromosomes of the acrocentric chromosomes and supernumerary marker chromosomes regarding to highlight of the formation mechanisms of co-existence of these two rearrangements.

Absence of the SLC22A12 gene mutation in Turkish population with primary gout disease

The aim of the study was to examine whether SLC22A12 gene mutations might be influenced in primary gout disease. We included 32 patients with diagnosis of primary gout disease and 100 healthy volunteers. DNA was purified from peripheral blood, and all exons of the SLC22A12 gene were sequenced. We did not find any mutations in the SLC22A12 gene in all of the patients, but found 5 polymorphisms in exons 1 (g.T258C, g.C246T), 2 (g.C1246T) and 8 (g.T8011C) and in intron 9 (g.C8577T). However, we have not found any significant differences in the frequency of the individual genotypes between patients with primary gout disease and control group. In addition, the polymorphisms were not associated with hyperuricemia in our patients with primary gout disease. There was no previously reported mutation/polymorphisms of SLC22A12 gene in Turkish population. Our study is the first one in Turkish population and suggests that there is no association between primary gout disease and SLC22A12 gene polymorphisms. Sequence changes in the promotor and intronic regions of SLC22A12 gene should be investigated further with larger case groups.

A patient with Down syndrome with a de novo derivative chromosome 21

Pure partial trisomy of chromosome 21 is a rare event. The patients with this aberration are very important for setting up precise karyotype-phenotype correlations particularly in Down syndrome phenotype. We present here a patient with Down syndrome with a de novo derivative chromosome 21. Karyotype of the patient was designated as 46,XY,der(21)(p13)dup(21)(q11.2q21.3)dup(21)(q22.2q22.3) with regard to cytogenetic, FISH and array-CGH analyses. Non-continuous monosomic, disomic and trisomic chromosomal segments through the derivative chromosome 21 were detected by array-CGH analysis. STR analyses revealed maternal origin of the de novo derivative chromosome 21. The dual-specificity tyrosine (Y)-phosphorylation regulated kinase 1A (DYRK1A) and Down Syndrome Critical Region 1 (DSCR1) genes that are located in Down syndrome critical region, are supposed to be responsible for most of the clinical findings of Down syndrome. However, our patient is the first patient with Down syndrome whose clinical findings were provided in detail, with a de novo derivative chromosome 21 resulting from multiple chromosome breaks excluding DYRK1A and DSCR1 gene regions.

Aberrations of chromosomes 9 and 22 in acute lymphoblastic leukemia cases detected by ES-fluorescence in situ hybridization

A reciprocal translocation between chromosomes 9 and 22 creates oncogenic BCR/ABL fusion in the breakpoint region of the derivative chromosome 22. The aim of this study was to evaluate the importance of atypical fluorescence in situ hybridization (FISH) signal patterns in pediatric and adult acute lymphoblastic leukemia (ALL) cases. We evaluated t(9;22) translocation in 208 cases with ALL (294 tests), including 139 childhood and 69 adult cases by FISH technique using BCR/ABL extra signal (ES) probe. FISH signal patterns observed in pediatric ALL cases were as follows; Major-BCR/ABL (M-BCR/ABL) (1.4%), minor-BCR/ABL (m-BCR/ABL) (3.6%), trisomy 9 (4.3%), trisomy 22 (4.3%), trisomy or tetrasomy of both chromosomes 9 and 22 (2.9%), monosomy 9 (1.4%), monosomy 22 (0.7%), ABL gene amplification (1.4%), derivative chromosome 9 deletion (1.4%), and extra copies of the Philadelphia chromosome (1.4%). FISH signal patterns observed in adult ALL cases were as follows; M-BCR/ABL (5.8%), m-BCR/ABL (11.6%), two different cell clones with major and minor BCR/ABL signal pattern (2.9%), extra copies of Philadelphia chromosome (4.3%), derivative chromosome 9 deletion (1.4%), trisomy 9 (2.9%), tetraploidy (1.4%), monosomy 9 (1.4%), trisomy 22 (1.4%), and coexistence of both trisomy 22 and monosomy 9 (1.4%). Trisomy 9, trisomy 22, and polyploidy of chromosomes 9 and 22 were specific atypical FISH signal patterns for childhood B cell acute lymphoblastic leukemia (B-ALL) patients. However, monosomy 9 and ABL gene amplification were highly specific for childhood T cell acute lymphoblastic leukemia (T-ALL) patients. Our report presents the correlation between atypical FISH signal patterns and clinical findings of a large group of ALL cases.

Prenatal diagnosis of β-thalassemia and other hemoglobinopathies in southwestern Turkey

Our aim was to evaluate the prenatal diagnosis of β-thalassemia (β-thal) and other hemoglobinopathies in a region with high frequency. After detection by premarital or antenatal screening, 312 patients underwent 420 prenatal diagnostic procedures for 407 fetuses in a 10-year period. Fetal samples were collected by chorionic villi sampling (CVS) in the first trimester and amniocentesis and cordocentesis in the second trimester. Mutation analyses of β-globin and cytogenetic analyses were performed and the most common mutations detected were: IVS-I-110 (G>A), IVS-II-1 (G>A), IVS-I-6 (T>C) and IVS-II-745 (C>G). Hb S [β6(A3)Glu→Val, GAG>GTG)] was the most common hemoglobin (Hb) variant with a frequency of 6.3%. Among 407 fetuses, 105 (25.8%) were diagnosed as affected, while 201 (49.4%) were carriers and 101 (24.8%) were normal. Cytogenetic analyses revealed nine fetuses (2.3%) with numerical chromosomal abnormalities as regular or mosaicism. Prenatal diagnosis of common hemoglobinopathies is safe and effective. Performing cytogenetic analysis in excess fetal material is an acceptable option.

De novo supernumerary marker chromosome originating from chromosome 17 resulting in a normal pregnancy outcome

We report here a prenatal case with de novo supernumerary marker chromosome originating from chromosome 17 in non-mosaic form resulting in normal pregnancy outcome. In this case, a 26-year-old pregnant woman was referred for amniocenthesis and microdeletion Fluorescence In Situ Hybridization (FISH) testing at 18 weeks of gestation due to history of a previous child with Angelman Syndrome. PWS/AS region deletion was excluded by FISH. A de novo supernumerary, non-satellited, monocentric marker chromosome was detected during conventional cytogenetic analysis. With the use of FISH testing, it was found that the marker chromosome originated from chromosome 17. Additionally, the marker chromosome was found not to contain the Smith-Magenis and Miller Dieker syndrome regions. After detailed review of the literature, genetic counseling was given to the family, and the family decided to continue the pregnancy to term. A female child was born at term without any phenotypical abnormalities and clinical complications. Follow-up at 15 months-of-age revealed no developmental abnormalities. To our knowledge, our patient is the first reported prenatal case with a de novo monocentric, supernumerary marker chromosome derived from chromosome 17 in a non-mosaic form that resulting in normal pregnancy outcome.

Prenatal diagnosis of a de novo supernumerary marker chromosome originating from chromosome 16

Prenatal diagnosis of a de novo supernumerary marker chromosome originating from chromosome 16: A 37 year old pregnant woman was referred for amniocentesis at 18 weeks of gestation due to advanced maternal age and abnormal serum biochemistry. A nonsatellited, monocentric marker chromosome was observed with a frequency of 57% in cultured amniocytes. Parental karyotypes were normal. The marker chromosome was found to be derived from chromosome 16 by FISH using CEP16 and WCP16 probes. Marker chromosomes were not painted with M-FISH probe mixture, indicating an exclusively heterochromatin nature. CGH analysis using genomic DNA isolated from uncultured amniocytes also supported the M-FISH results. Genetic counseling was given to parents and the family decided to continue the pregnancy to term. The baby was born at 36 weeks of gestation without any dysmorphic features. Follow-up at 7 months of age revealed no developmental abnormalities.

Maternal origin and clinical findings in a case with trisomy 22

We report a newborn girl with multiple congenital anomalies whose chromosomal analysis showed complete trisomy 22. Her phenotype included microcephaly, epicanthus, hypertelorism, micrognathia, cleft palate, microtia, and preauricular tag. She died in the 24th post-natal hour. Trisomy 22 was shown by fluorescence in situ hybridization technique and the parental origin of the extra chromosome was found to be maternal by DNA microsatellite marker analysis of chromosome 22. Postmortem examination revealed the presence of atrioseptal defect and stasis in the biliary canals. We believe that this patient will contribute to the literature both by clinical findings and short life span associated with maternal origin of extra chromosome 22.

An unusual case of chromosome 22q11 deletion syndrome with psychiatric disorder, hypoparathyroidism and precocious puberty

Deletions of chromosome 22q11 cause a wide range of phenotypes; even affected members from the same family may present with different phenotype. We present an 11-3/12 year-old boy who has 22q11 deletion in a hitherto unreported combination with psychiatric disorder, hypoparathyroidism and precocious puberty. Whether precocious puberty is a clue for chromosome 22q11 deletion syndrome is also discussed.

Role of magnetic resonance imaging in the early diagnosis of Takayasu arteritis

Takayasu arteritis is a non-specific inflammatory process of unknown aetiology affecting the aorta and its major branches. It may lead to stenosis or occlusion. We have examined eight patients with clinically diagnosed Takayasu arteritis using contrast-enhanced MRI and also 3-D MR angiography. All patients were female and their ages varied between 22 and 48 years. We were able to show subtle arteritic changes and stenotic lesions in branch vessels in the early phase of the disease by using this imaging modality. Thus, we can state that contrast-enhanced MRI with 3-D MR angiography can be used for the initial diagnosis of Takayasu arteritis. It provides a means to evaluate the vascular tree non-invasively and may replace conventional angiography.

Novel cytogenetic findings revealed by conventional cytogenetic and FISH analyses in leukaemia patients

AIM

To describe novel cytogenetic findings in four leukaemia patients.

METHODS

Conventional cytogenetic (CC) and fluorescence in situ hybridization (FISH) analyses were performed on bone marrow samples of four leukaemia patients.

RESULTS

In this study, t(3;10)(q11;q25) and t(2;22)(p21;q11.2) were detected as novel translocations. t(8;16;21)(q22.1;q13;q22) and t(1;6;9;22)(p36.1;p21.3;q34;q11) were found as variant translocations, and these variant translocations were confirmed by Interphase-FISH and Multi-colour-FISH.

CONCLUSION

Newly identified cytogenetic findings can lead us to characterize cytogenetic evolution of the haematological malignancies. Further investigations are certainly warranted to resolve the prognostic impact of these new cytogenetic abnormalities.

M-FISH applications in clinical genetics

Until recently, presence of de novo marker or derivative chromosomes was quite problematic for genetic counseling especially in prenatal diagnosis, because characterization of marker and derivative chromosomes by conventional cytogenetic techniques was nearly impossible. However, recently developed molecular cytogenetic technique named Multicolor Fluorescence in Situ Hybridization (M-FISH) which paints all human chromosomes in 24 different colors allows us to characterize marker and derivative chromosomes in a single hybridization. In this study, we applied M-FISH to determine the origin of 3 marker and 3 derivative chromosomes. Marker chromosomes were found to originate from chromosome 15 in two postnatal and one prenatal case. Of these, one of the postnatal cases displayed clinical findings of inv dup (115) syndrome and the other of infertility, and the prenatal case went through amniocentesis due to the triple test results. Karyotypes of the patients with derivative chromosomes were designated as 46,XY,der (21)t(1;21)(q32;p11), 46,XX,der(8)t(8;9)(p23;p22) and 46,XX,der(18)t(18;20)(q32;p11.2) according to cytogenetic and M-FISH studies. All of the M-FISH results were confirmed with locus specific or whole chromosome painting probes. The case with der (8)t(8;9) had trisomy 9(p22-pter) and monosomy 8(p23-pter) due to this derivative chromosome. The case with der(18)t(18;20) had trisomy 20(p11.2-pter) and monosomy 18(q32-qter). Parental origins of the derivative chromosomes were analyzed using microsatellite markers located in the trisomic chromosomal segments. Patients' clinical findings were compared with the literature.

Telomere-specific fluorescence in situ hybridization analysis of couples with five or more recurrent miscarriages

Fluorescence in situ hybridization analysis using telomere specific probes has been used to detect cryptic translocations in the chromosomal telomeric regions. This study was performed in five clinically normal couples who have had five or more spontaneous abortions and whose karyotypes were found to be normal using conventional cytogenetic techniques. Using the telomere specific probes, in one couple we determined a cryptic translocation between chromosome 3 and 10, and, in another couple, the signal in chromosome 20 was detected in another chromosome, which was probably a D group chromosome. Additionally, in the latter and also in two other couples, we observed a polymorphism. The approach will be helpful for screening cryptic translocations using telomere specific multiple probe sets in couples with recurrent miscarriages. As prenatal diagnosis will be available for these couples for future pregnancies, it will be possible to help these families to have healthy fetuses.