Hydrops fetalis secondary to Bart hemoglobinopathy

A Rare Hb H Hydrops Fetalis Syndrome Caused by the - -SEA Deletion in Combination with the Rare Hb Hirosaki Mutation in a Chinese Patient

Despite the milder clinical severity of Hb H patients compared with those of Hb Bart's hydrops fetalis or patients with β-thalassemia major (β-TM), a few cases of Hb H hydrops fetalis syndrome have been reported so far. Here, we describe, for the first time in the Chinese population, one case of a neonate with Hb H hydrops fetalis syndrome caused by the - -^SEA (Southeast Asian) deletion in combination with the Hb Hirosaki (HBA2: c.132C>G, p.Phe43Leu) mutation. Our study highlights the importance of continuous fetal monitoring using ultrasonography and blood screening studies of fetuses. Appropriate genetic counseling and comprehensive clinical follow-up should be performed on a pregnant woman who carried an α⁰-thalassemia (α⁰-thal) deletion and had a Hb H or Hb Bart's hydrops fetalis offspring, especially if the woman's partner also carried a hemoglobinopathy.

Invasive prenatal diagnosis of α-thalassemia to control Hb Bart's hydrops fetalis syndrome: 15 years of experience

PURPOSE

The aim of the present study was to report experiences with invasive prenatal diagnosis of α-thalassemia for the prevention of Hb Bart's hydrops fetalis syndrome in the Guangxi Zhuang Autonomous Region, China.

METHODS

Pregnant women and their partners who tested positive for α⁰-thalassemia or were diagnosed with HbH diseases were counseled and suggested to undergo a prenatal diagnostic procedure for α-thalassemia. Fetal material was obtained by chorionic villus sampling (CVS) between 9 and 13 weeks of gestation, by amniocentesis between 16 and 24 weeks of gestation and by cordocentesis after 24 weeks of gestation. The α⁰-thalassemia gene types were detected by gap polymerase chain reaction (Gap-PCR). All results were finally confirmed by DNA analysis after delivery or termination of pregnancy.

RESULTS

An invasive prenatal α-thalassemia diagnosis was performed in 3155 cases at risk for Hb Bart's hydrops fetalis syndrome at our hospital from 2002 to 2016. CVS was performed in 1559 cases (49.4%), amniocentesis in 1240 cases (39.3%) and cordocentesis in 356 cases (11.3%). In total, 786 fetuses were diagnosed as Hb Bart's hydrops fetalis syndrome. Among these cases, the α-thalassemia genotype was --^SEA/--^SEA in 784 cases and --^SEA/--^THAI in 2 cases. All affected pregnancies were terminated in time.

CONCLUSIONS

This extensive experience suggests that carrier screening, molecular diagnostics, genetic counselling, and prenatal diagnosis are effective measures to prevent Hb Bart's hydrops fetalis syndrome.

Perspectives in Pediatric Pathology, Chapter 22. Testicular Involvement in Systemic Diseases

Normal testicular physiology requires appropriate function of endocrine glands and other tissues. Testicular lesions have been described in disorders involving the hypothalamus-hypophysis, thyroid glands, adrenal glands, pancreas, liver, kidney, and gastrointestinal tract. Testicular abnormalities can also associate with chronic anemia, obesity, and neoplasia. Although many of the disorders that affect the above-mentioned glands and tissues are congenital, acquired lesions may result in hypogonadism in children and adolescents.

An international registry of survivors with Hb Bart's hydrops fetalis syndrome

Hemoglobin (Hb) Bart's hydrops fetalis syndrome (BHFS) resulting from α0-thalassemia is considered a universally fatal disorder. However, over the last 3 decades, improvements in intrauterine interventions and perinatal intensive care have resulted in increasing numbers of BHFS survivors. We have initiated an international registry containing information on 69 patients, of which 31 are previously unpublished. In this perspective, we analyze the available clinical information to document the natural history of BHFS. In the future, once we have accrued sufficient cases, we aim to build on this study and provide information to allow counseling of at-risk couples. To date, 39 patients have survived beyond the age of 5 years, 18 of whom are now older than 10 years. Based on the available cases, we find evidence to suggest that intrauterine therapy provides benefits during the perinatal and neonatal period; however, it may not provide additional benefits to long-term growth and neurodevelopmental outcomes. Growth retardation is a major adverse long-term outcome among BHFS patients with ∼40% being severely affected in terms of weight and ∼50% in terms of height. There is also an increased risk of neurodevelopmental delay as we find 20% (11/55) of BHFS survivors suffer from a serious delay of ≥6 months. Most patients in the registry require lifelong transfusion and often have associated congenital abnormalities and comorbidities. This perspective is a first step in gathering information to allow provision of informed counseling on the predicted outcomes of affected babies.

Alpha-thalassaemia

Alpha-thalassaemia is inherited as an autosomal recessive disorder characterised by a microcytic hypochromic anaemia, and a clinical phenotype varying from almost asymptomatic to a lethal haemolytic anaemia.

It is probably the most common monogenic gene disorder in the world and is especially frequent in Mediterranean countries, South-East Asia, Africa, the Middle East and in the Indian subcontinent. During the last few decades the incidence of alpha thalassaemia in North-European countries and Northern America has increased because of demographic changes. Compound heterozygotes and some homozygotes have a moderate to severe form of alpha thalassaemia called HbH disease. Hb Bart's hydrops foetalis is a lethal form in which no alpha-globin is synthesized. Alpha thalassaemia most frequently results from deletion of one or both alpha genes from the chromosome and can be classified according to its genotype/phenotype correlation. The normal complement of four functional alpha-globin genes may be decreased by 1, 2, 3 or all 4 copies of the genes, explaining the clinical variation and increasing severity of the disease. All affected individuals have a variable degree of anaemia (low Hb), reduced mean corpuscular haemoglobin (MCH/pg), reduced mean corpuscular volume (MCV/fl) and a normal/slightly reduced level of HbA₂. Molecular analysis is usually required to confirm the haematological observations (especially in silent alpha-thalassaemia and alpha-thalassaemia trait). The predominant features in HbH disease are anaemia with variable amounts of HbH (0.8-40%). The type of mutation influences the clinical severity of HbH disease. The distinguishing features of the haemoglobin Bart's hydrops foetalis syndrome are the presence of Hb Bart's and the total absence of HbF. The mode of transmission of alpha thalassaemia is autosomal recessive. Genetic counselling is offered to couples at risk for HbH disease or haemoglobin Bart's Hydrops Foetalis Syndrome. Carriers of alpha⁺- or alpha⁰-thalassaemia alleles generally do not need treatment. HbH patients may require intermittent transfusion therapy especially during intercurrent illness. Most pregnancies in which the foetus is known to have the haemoglobin Bart's hydrops foetalis syndrome are terminated due to the increased risk of both maternal and foetal morbidity.

Causes and consequences of 93 fetuses with cardiomegaly in a tertiary center in Thailand

OBJECTIVES

To assess etiology, perinatal mortality and associated factors of fetal cardiomegaly (FC).

METHODS

A retrospective study of fetuses with cardiomegaly was conducted. Demographic data, ultrasonographic findings, and outcomes were collected and analyzed.

RESULTS

Ninety-three fetuses were analyzed. The causes of FC were cardiac causes 49.5%, Bart's hemoglobinopathies 28%, and non-Bart's anemia 15%. Ascites, pericardial effusion, and hydrops were more prevalent in fetuses with anemia than those with cardiac abnormalities. The overall perinatal mortality was 69.9%. Although all Bart's hydrops died, perinatal mortality of non-Bart's anemia, and structural cardiac defect were 57.1 and 69.7%, respectively. Excluding Bart's anemia, receiver-operating characteristic curve analysis demonstrated that cardiothoracic ratio of ≥0.58 best predictive for perinatal mortality. Earlier gestational age at diagnosis, skin edema, and chromosomal abnormality were associated with higher mortality.

CONCLUSIONS

Majority causes of FC were cardiac and anemic in origin. It carried high-perinatal mortality depending on the causes.

[Major alpha-thalassemia: antenatal diagnosis, case report and literature review]

Homozygous alpha-thalassaemia or Bart's hydrops fetalis is a genetic disease with autosomal recessive transmission. The condition is lethal for the fetus because of hypoxia and anemia. For the mother there is an increased risk of the severe forms of preeclampsia and its complications. The diagnosis can be suspected in presence of suggestive ultrasonographic anomalies, where both parents come from South-East Asia or China. Confirmation is based on the identification of the typical deletions or mutation of the alpha globin gene by molecular genetics. We report a rare clinical case of Bart's hydrops fetalis diagnosed because of fetal growth retardation, fetal cardiomegaly and increased size of placenta on the 26 weeks fetal echography. This case underscores the need to include the alpha thalassemias in medical and midwifery education in countries where they were almost inexistent a generation ago.

The effect of hypoxia in development

There is increasing evidence that the oxygen supply to the human embryo in the first trimester is tightly controlled, suggesting that too much oxygen may interfere with development. The use of hypoxia probes in mammalian embryos during the organogenic period indicates that the embryo is normally in a state of partial hypoxia, and this may be essential to control cardiovascular development, perhaps under the control of hypoxia-inducible factor (HIF). A consequence of this state of partial hypoxia is that disturbances in the oxygen supply can more easily lead to a damaging degree of hypoxia. Experimental mammalian embryos show a surprising degree of resilience to hypoxia, with many organogenic stage embryos able to survive 30-60 min of anoxia. However, in some embryos this degree of hypoxia causes abnormal development, particularly transverse limb reduction defects. These abnormalities are preceded by hemorrhage/edema and tissue necrosis. Other parts of the embryo are also susceptible to this hypoxia-induced damage and include the genital tubercle, the developing nose, the tail, and the central nervous system. Other frequently observed defects in animal models of prenatal hypoxia include cleft lip, maxillary hypoplasia, and heart defects. Animal studies indicate that hypoxic episodes in the first trimester of human pregnancy could occur by temporary constriction of the uterine arteries. This could be a consequence of exposure to cocaine, misoprostol, or severe shock, and there is evidence that these exposures have resulted in hypoxia-related malformations in the human. Exposure to drugs that block the potassium current (IKr) can cause severe slowing and arrhythmia of the mammalian embryonic heart and consequently hypoxia in the embryo. These drugs are highly teratogenic in experimental animals. There is evidence that drugs with IKr blockade as a side effect, for example phenytoin, may cause birth defects in the human by causing periods of embryonic hypoxia. The strongest evidence of hypoxia causing birth defects in the human comes from studies of fetuses lacking hemoglobin (Hb) F. These fetuses are thought to be hypoxic from about the middle of the first trimester and show a range of birth defects, particularly transverse limb reduction defects.

Vascular-type disruptive defects in fetuses with homozygous α-thalassemia: report of two cases and review of the literature

BACKGROUND

The thalassemias are an inherited group of heterogeneous anemias in which one or more of the globin chains in the hemoglobin tetramer are absent. Fetuses with homozygous alpha-thalassemia, which is particularly prevalent in people of Southeast Asian extraction, experience deficient alpha-globin chain synthesis and cannot produce hemoglobin F (the primary fetal hemoglobin after 8 weeks' gestation). Instead, they produce an anomalous hemoglobin, hemoglobin Bart's, with an unusually high affinity for oxygen, leading to profound anemia and tissue hypoxia.

METHODS AND RESULTS

Here we report on two fetuses with homozygous alpha-thalassemia who displayed structural defects of a vascular disruptive type. Both fetuses demonstrated limb anomalies, including terminal transverse limb deficiencies, and one fetus was found to have a brain malformation consisting of a neuronal migrational defect. The limb anomalies and suspected brain malformation were detected on prenatal ultrasound prior to confirmation of the diagnosis of alpha-thalassemia in one case; in the other case prenatal records were not available. While microcephaly, hydrocephalus, and retarded brain growth have been rarely reported in association with homozygous alpha-thalassemia, this is the first report of a true brain malformation in an affected fetus. Limb anomalies, on the other hand, appear to be more frequent. Recently, aggressive in utero and postnatal therapies for homozygous alpha-thalassemia have been attempted with some success.

CONCLUSIONS

Our cases and those from the medical literature suggest that couples need to be counseled about the risks of congenital anomalies of a vascular disruptive type in affected fetuses. Furthermore, data from the literature suggests that in utero therapy may not significantly decrease these risks as such anomalies may be present prior to the institution of therapy. In addition, in hydropic infants with vascular disruptive defects, especially in those of Southeast Asian origin, homozygous alpha-thalassemia should be suspected as a likely etiology.

Testing for hematologic disorders and complications

This review summarizes state-of-the-art and emerging techniques in the antenatal diagnosis of fetal anemia and hemoglobinopathies. Fetal anemia may result from hemolytic disease, hemorrhage, suppression of erythropoiesis, infection (eg, parvovirus B19), or trauma. The clinical laboratory plays an essential role in the evaluation of these disorders by way of the use of various hematologic, biochemical, serologic, cytometric, and molecular genetics methods. Hemoglobinopathies are the most common class of single gene disorders worldwide. The authors have used the example of homozygous alpha-thalassemia major (Hb Barts disease) as a paradigmatic case for antenatal hemoglobinopathy screening. Perhaps the most familiar indication for hematologic screening in pregnancy is HDFN, most commonly in pregnancies previously sensitized to the RhD antigen. All pregnant women, regardless of their past medical or obstetric history or previous antibody screens, should have ABO/Rh blood typing and a red cell antibody screen performed at the first prenatal visit. Long-established methods for assaying FMH (KB method), microcytosis (hemogram with red cell indices), and blood group incompatibility (direct antigen test, serologies) remain critical for rapid, sensitive diagnosis. Analysis of fetal free DNA in maternal plasma holds the promise for rapid, ultrasensitive, and noninvasive detection of many fetal hematologic disorders.

Hb H hydrops foetalis syndrome: a case report and review of literature

Haemoglobin H (Hb H) disease is caused by deletion or inactivation of three alpha-globin genes, leaving only one intact and active alpha-globin gene. People with Hb H disease usually have moderate anaemia, but are generally thought to be asymptomatic. Some Hb H disease patients require transfusions, and there are reports of fetuses with Hb H disease who have severe anaemia in utero resulting in fatal hydrops foetalis syndrome. We now report a case of Hb H hydrops foetalis syndrome, caused by the inheritance of a hitherto novel alpha-globin gene point mutation (codon 35 TCC-->CCC or Serine-->Proline) and an alpha-thalassaemia deletion of the Filipino type removing all zeta-alpha-globin genes on the other chromosome 16. The infant was delivered prematurely because of pericardial effusion and fetal distress, and was found to have severe anaemia and congenital anomalies. A review of the relevant literature on this syndrome is presented, and serves to underscore the phenotypic variations of Hb H disease and the need for surveillance for this condition among newborns and genetic counselling in communities with a high proportion of at-risk populations.

Changing outcome of homozygous alpha-thalassemia: cautious optimism

Only a few long-term survivors of homozygous alpha-thalassemia, a usually fatal condition, have been reported. The authors present a surviving infant with this disorder and discuss the complications, treatments, and implications of this genetic hemoglobinopathy. The child had no antenatal intervention and has been treated with regular transfusions. She has had normal growth and development and is currently 2.5-years-old. A literature review of survivors with Bart hemoglobinopathy reveals an intense perinatal course and a great prevalence of congenital urogenital and limb defects. Advances in antenatal diagnosis, intrauterine intervention, and postnatal treatments have resulted in extended survival of children with congenital defects that until recently were considered invariably fatal. Transfusion and chelation therapy and bone marrow transplantation provide long-term treatment and potential curative options.

Limb defects and congenital anomalies of the genitalia in an infant with homozygous alpha-thalassemia

We describe an infant with homozygous alpha-thalassemia, genital abnormalities, and terminal transverse limb defects, whose limbs demonstrate evidence of loss of tissue and abnormal morphogenesis. We propose these defects were due to either severe fetal anemia or to vascular occlusion by abnormal erythrocytes, resulting in hypoxia of the developing distal limbs and genitalia.

Limb defects in homozygous alpha-thalassemia: report of three cases

Homozygosity for the South-Asian alpha-thalassemia (--SEA/) deletion is a serious hematological condition that results, in most cases, in intrauterine or postnatal death due to anemia and severe hypoxia of prenatal onset. A relationship between congenital abnormalities and intra-uterine hypoxia has been postulated. However, since homozygosity for the (--SEA/) deletion is most common in underdeveloped countries where detailed autopsies are lacking, the incidence of congenital abnormalities among these babies has not been well delineated. We report on three newborn infants, homozygous for the (--SEA/) deletion, who were born with limb defects. We postulate that this combination is the result of prenatal hypoxia which may affect other fetal body organs. This should be taken into consideration when prenatal treatment of affected fetuses, with intrauterine blood transfusion, is suggested.

Ultrasonographic scanning of placental thickness and the prenatal diagnosis of homozygous alpha-thalassaemia 1 in the second trimester

In order to evaluate the association between placental thickness (PT) and fetal homozygous alpha-thalassaemia 1 before the appearance of classic ultrasound findings of haemoglobin (Hb) Bart's hydrops fetalis, a total of 473 pregnancies were collected. The control group included 422 normal pregnancies with a gestational age from 14 to 23 weeks and the study group included 51 affected fetuses in the same gestational period. Fetal biparietal diameter (BPD) and PT were measured by high-resolution ultrasound. PT was evaluated against BPD. In the control group, the PT generally increased in parallel with the advancement of gestational age. All PT measurements in the study group were above the mean PT of their respective gestational week in the control group. Forty-six (90 per cent) of the pregnancies in the study group had PT larger than the mean plus two standard deviations of the control group. This study suggests that ultrasound measurement of PT may be a useful aid in the prenatal diagnosis of Hb Bart's hydrops fetalis before its classic findings become apparent in the late second trimester or third trimester.

Increased level of second trimester maternal serum chorionic gonadotropin in pregnancy with a fetus affected by homozygous alpha-thalassemia 1

With enzyme immunoassay, maternal serum chorionic gonadotropin (MShCG) level was determined in 58 pregnancies affected with fetal homozygous alpha-thalassemia 1. In 40 pregnancies with a gestational age of 10 to 14 weeks, 8 (20%) had an MShCG level above 2.5 multiples of the median (MoM); while in the other 18 pregnancies with a gestational age of 15 to 23 weeks, 14 (78%) had a level above 2.5 MoMs and none had a level below the median. Homozygous alpha-thalassemia 1 of the fetus was associated with an elevated MShCG. Therefore in second-trimester screening for Down's syndrome by measurement of MShCG, homozygous alpha-thalassemia 1 should also be considered if elevated MShCG levels are found.

Detection of the (--SEA) double alpha-globin gene deletion by a simple immunologic assay for embryonic zeta-globin chains

Homozygous alpha-thalassemia [alpha-thal-1], with loss of all four alpha-globin genes, causes lethal hydrops fetalis. The most common mutation producing this syndrome is the Southeast Asian (--SEA) double alpha-globin gene deletion. Erythrocytes from adults heterozygous for the (--SEA) deletion have minute amounts of embryonic zeta-globin chains detectable by anti-zeta-globin monoclonal antibodies. Among 225 peripheral blood samples tested by a simple anti-zeta-immunobinding tetrazolium dye test, 81 were positive and 144 were negative. The majority of subjects were of Filipino, Chinese, or Laotian ancestry. All 81 positive samples were confirmed by Bam HI digests and a zeta-cDNA probe to have the (--SEA) mutation. The (--SEA) double alpha-deletion was the only abnormality in 58. In the others, it was combined with alpha-globin or beta-globin mutations, or coincidental iron deficiency. Four other samples from (--SEA) heterozygotes were negative by this immunologic assay. Anti-zeta negative samples included 78 deletions of the total alpha-globin region, (--Tot), 23 single alpha-globin deletions, and a variety of beta-globin mutations; 16 normocytic samples with normal alpha-genes were also negative. Ten anti-zeta positive and 25 anti-zeta negative samples had benign triplicated zeta-globin genes. In this population, the sensitivity of this test was 95%; and specificity for the (--SEA) mutation was 100%. Anti-zeta immunobinding testing provides rapid, simple, and reliable screening for the (--SEA) double alpha-globin deletion, although it does not detect the (--Tot) total alpha-deletions.

The perinatal autopsy: a contemporary approach

As autopsy rates in general hospitals decline, interest in the perinatal autopsy continues to rise, reflecting the emergence of a vigorous specialty growing in parallel with fetal medicine, prenatal diagnosis and clinical genetics. Perinatal autopsies are best carried out in tertiary centres which provide these services. Meticulous documentation, flexibility of technique, intelligent use of laboratory tests and wide systematic histopathologic sampling are emphasized. Microbiologic examination is of particular value when carried out by a laboratory having a special interest in genital tract and perinatal pathogens. Karyotyping must be selective if resources are to be conserved and is most productive when there are multiple malformations. Perinatal autopsy is not complete without examination of the placenta and significant lesions should be clearly distinguished from curiosities and from changes secondary to fetal death. The pathologist's wider contribution to perinatal medicine includes providing high quality data to epidemiology units and auditing committees, contributing to the multidisciplinary management of prenatally diagnosed fetal abnormalities, monitoring iatrogenic disease patterns and supporting the process of perinatal grief management. Special problems and diagnostic challenges are to be found when investigating sudden, unexplained intrauterine fetal death, hydrops, bone dysplasias and complicated multiple pregnancies.

Molecular characterization of severe alpha-thalassemias causing hydrops fetalis in Taiwan

alpha-Thalassemia hydrops fetalis is a common disorder in Taiwan. The condition causes perinatal death and many maternal obstetrical complications. In order to determine the molecular defects of this condition in Chinese, 87 unrelated families with this disorder were collected in the past 4 years. The molecular defects were studied by Southern blotting and DNA hybridization with phi zeta 1-globin gene and LO (a 0.4 kb BamHI/EcoRI fragment in the 5' flanking region of the zeta 2-globin gene) probes. Eighty-one (93.1%) fetuses had homozygous Southeast Asian deletion (- -SEA/- -SEA). Five (5.7%) fetuses were compound heterozygotes for the Southeast Asian deletion and Thailand deletion (- -SEA/- -THAI). The remaining fetus was a compound heterozygote for the Southeast Asian deletion and an uncharacterized nondeletional defect (- -SEA/(alpha alpha)Th). The molecular defects of alpha-thalassemia hydrops fetalis in Chinese are heterogeneous. This fact has important implications for genetic counseling and prenatal diagnosis.

Hydrops revisited: literature review of 1,414 cases published in the 1980s

This paper reviews 47 series of hydrops fetalis (804 cases) and 610 individual cases published since 1980. From this large number of cases, guidelines are derived for prenatal diagnosis and management.

Bart's hydrops fetalis--clinical presentation and management--an analysis of 25 cases

Twenty-nine hydropic infants were born in the Kandang Kerbau Hospital between 1980 and 1985, during which there were 131,658 deliveries, giving an incidence of 1 in 4,540 total births. Twenty-five of these cases were confirmed to be due to homozygous alpha thalassaemia. No case of fetal hydrops due to Rh isoimmunization was detected. The mean age of the mothers was 28.86 +/- 4.05 years (+/- SD). Eight patients had delivered 1 hydropic baby previously while 1 had a history of 2 babies with hydrops fetalis; 92% of the patients had been followed antenatally while 8% were first seen when they were admitted in labour; 25% of the patients had anaemia, 52% had polyhydramnios, 20% developed hypertension and 64% had bilateral lower limb oedema. None of the patients had concomitant hypertension, generalized oedema and proteinuria. In 4 cases of recurrent hydrops, serial ultrasound scans were performed from early pregnancy but ultrasonic features of hydrops fetalis were only seen from 27 weeks' gestation. Spontaneous labour occurred in 75% of patients at a mean of 32.3 +/- 3.3 weeks (+/- SD). All delivered vaginally and only 1 patient required abdominal decompression. Four patients required Caesarean section, 2 for failure to progress after induction of labour, 1 for major placenta praevia and the fourth for fetal distress; in the last case, diagnosis of hydrops fetalis was only made after delivery of the baby. All the babies in the series died within one hour of delivery. Homozygous alpha thalassaemia is the commonest cause of hydrops fetalis in Singapore and is an invariably fatal condition. It is associated with an increased incidence of maternal anaemia, polyhydramnios and prematurity.

The different types of alpha-thalassemia: practical and genetic aspects

From May 1985 to October 1987, 1,564 Southeast Asians living in Hawaii were screened for hereditary anemias. Microcytosis was determined by electronic red cell indices and morphology; iron deficiency was ruled out by normal red cell distribution width and normal protoporphyrin levels; Hb E was determined by electrophoresis; beta-thalassemia (thal) heterozygotes were identified by raised Hb A2 on column chromatography. alpha-Thalassemia heterozygotes were diagnosed by exclusion. Family studies helped identify or confirm diagnoses, especially for the alpha-thal-2 heterozygotes (-alpha/alpha alpha) and homozygotes (-alpha/-alpha). Provisional diagnoses are being checked by DNA analyses. Iron deficiency prevented detection of possibly coexisting alpha-thalassemias in 97 individuals. Technical problems included the obscuring of standard criteria for recognizing the alpha-thal variants by the presence of Hb E or beta-thal. In such cases, alpha-thal could only be detected by family studies or DNA analyses. Problems with hemoglobin (Hb) electrophoresis included Hb H migrating beyond the edge of the strip if incubation was not closely monitored, and difficulty in detecting the small amounts of unstable Hb Constant Spring. DNA analyses also had limitations, since the nondeletion alpha-thalassemias would not be detected by routine Southern blotting. DNA analyses suggested that about 50% of presumed alpha-thalassemias were alpha-thal-2 (-alpha/alpha alpha) variants, and a corresponding number of alpha-thal-2 variants were among the apparent normals. Gene frequencies in the unselected Lao subjects were approximately 0.2 for Hb E, at least 0.1 for (-alpha), usually a rightward (alpha -3.7) type, 0.04 for (-), and 0.01 for a beta-thal. Multistep screening for the alpha- and beta-thalassemias was an effective and efficient strategy.

Theca-lutein ovarian cysts associated with homozygous alpha-thalassemia

We present a case of theca-lutein cysts associated with homozygous alpha-thalassemia. Theca-lutein cysts have been associated with various types of nonimmune hydrops fetalis but have not been reported previously in association with homozygous alpha-thalassemia.

Percutaneous ultrasound-guided fetal blood sampling in the management of nonimmune hydrops fetalis

Nonimmune hydrops fetalis can be caused by fetal chromosomal, hematologic, cardiac, or infectious conditions. A fetal blood sample obtained from percutaneous ultrasound-guided fetal blood sampling can offer vital information about the underlying cause of nonimmune hydrops fetalis, and perinatal management can be planned accordingly. Ten cases of nonimmune hydrops fetalis were investigated with percutaneous ultrasound-guided fetal blood sampling and subsequent fetal blood analysis. Nine were proved to be Bart's hemoglobin hydrops fetalis, with 78.2% to 99% of Bart's hemoglobin in the fetal blood. Terminations of pregnancy were undertaken immediately, resulting in a lowered maternal morbidity rate. Free cord loops or an intra-abdominal portion of the dilated umbilical vein can be used for percutaneous fetal blood sampling in nonimmune hydrops fetalis when the placental cord insertion is difficult to visualize. Percutaneous ultrasound-guided fetal blood sampling and subsequent fetal blood analysis will eventually play a key role in the management of the puzzling nonimmune hydrops fetalis if the safety of ultrasound-guided fetal blood sampling can be verified by further clinical studies.