Choosing among the physician databases.

Prudent examination and knowing how to ask the "right questions" can enable hospital marketers and planners to find the most accurate and appropriate database. The author compares the comprehensive AMA physician database with the less expensive MEDEC database to determine their strengths and weaknesses.

Nonuniform deficiency of hexosaminidase A in tissues and fluids of two unrelated individuals.

Serum samples from two unrelated, clinically normal individuals lacked detectable hexosaminidase A by heat inactivation and electrophoretic analysis. In contrast, 15 and 17% of the hexosaminidase in their leukocytes and 23 and 26% of the hexosaminidase of their cultured fibroblasts had the heat stability and electrophoretic properties of the A form of this enzyme. An in vitro measurement of fibroblasts GM2 ganglioside-beta-galactosaminidase was in the range expected for Tay-Sachs disease (TSD) heterozygotes (2.5 and 3.1 versus a normal mean of 3.7). In contrast, fibroblasts from a patient with TSD, analyzed in an identical fashion, contained no detectable activity. Ten days after addition of labeled GM2 ganglioside to the medium of the cultured fibroblasts, 43 and 59% of the radioactivity taken up by the cells of these patients remained as unhydrolyzed ganglioside as compared with 94% in TSD fibroblasts and 42% in control cells. An analysis of sphingolipid composition by high performance liquid chromatography although the endogenous level of GM2 was elevated in TSD fibroblasts (0.39 nmoles/mg protein) there was no increase in the cells of these patients (0 and 0.12 versus control of 0.17 nmoles/mg protein). Finally, the synthesis of hexosaminidase was examined by an electrophoretic analysis of immunoprecipitates of the enzyme precursors that had been radiolabeled by culturing fibroblasts in medium containing [3H]-leucine. These studies revealed a normal pattern of biosynthesis, processing and secretion of the alpha and beta chains. The ratio of the alpha chain to the beta chain, however, was in the range expected for TSD heterozygotes.

Spontaneous abortion after midtrimester amniocentesis.

Of 371 consecutive patients who underwent midtrimester diagnostic amniocentesis, 8 subsequently aborted spontaneously (2.2%), and 1 had a stillbirth at 24 weeks of gestation (0.17%). In 3 of the 9 patients who suffered fetal loss, infection appears to have played a significant role. Whereas midtrimester diagnostic amniocentesis is widely considered to be a safe and accurate procedure, the possibility of hazard to the patient and her fetus remains and should be considered during the preliminary counseling session.

Trisomy 21 in one of twin fetuses.

Both the detection of twins and the successful execution of a double amniocentesis pose significant technical problems in prenatal diagnosis. A case is reported in which one of twins fetuses had trisomy 21 and the other was chromosomally normal. Following counseling, the family chose to continue the pregnancy. At term, the mother was delivered of a healthy infant and a severely macerated fetus with stigmata suggestive of Down's syndrome.

Changes in alpha-fetoprotein levels in a case with multiple congenital anomalies.

PIP: A chromosomally normal women, who previously lost an infant with meningomyelocele and hydrocephalus, with a chromosomally normal husband, had normal alpha fetoprotein (AFP) levels in both amniotic fluid and maternal serum at about 19 weeks gestation. At 34 weeks, suspected hydramnios was confirmed clinically and radiographically; the latter showed no evidence of hydrocephalus. AFP levels at 36 weeks showed 224 ng/ml in maternal serum and 1249 ng/ml in amniotic fluid. Maternal serum rose from the 25th-19th percentile, and amniotic level was 5-fold greater than normal (200 ng/ml). At 39 weeks, abnormal AFP values of 258 and 1500 ng/ml for maternal serum and amniotic fluid, respectively, were measured. Though AFP patterns did not suggest an open neural tube defect (higher 19-week values were expected), spontaneous labor at 39 weeks resulted in a 1930-gm female with multiple congenital abnormalities. These AFP assays suggest: 1) that signaling of abnormalites other than neural tube defects is a valid use of AFP assays; 2) that the slope rather than single point values should be used in interpreting AFP results; 3) that assays in both amniotic fluid and maternal serum should be obtained and interpreted simultaneously in screening for birth defects; and 4) that sequential assays should be performed even in the presence of initially normal findings.^ieng

Return of fertility in a patient with cyclophosphamide-induced azoospermia.

A case of cyclophosphamide-induced azoospermia, followed three years later by the birth of a normal child to the patient's wife, is described. Genetic marker studies were carried out and strongly support identification of the patient as the true biologic father.

Prenatal cytogenetic analysis of women with high risk for genetic disorders.

PIP: 165 prenatal cytogenetic analyses are reported. The culture and Giemsa or quinacrine mustard (QM) staining processes are described. Karyotypes from both Giemsa and QM metaphases were analyzed. The main indications for amniocentesis were: 1)previous child with Down's syndrome (65), 2)advanced maternal age (74), 3)D/G carrier (5), 4)Duchenne muscular dystrophy (5) or 6)previous indication of other chromosomal anomaly. In the advanced maternal age group, 4 G21 and 1 E18 trisomy fetuses were detected. No chromosomal abnormalities were seen in the group referred for a previous child with Down's syndrome, although one woman was found to have a 9/13 translocation herself. Another woman with 13/14 translocation gave birth to a healthy boy with a 13/14 translocation, as predicted. Of 5 women referred for D/G translocation carriers, 1 had a fetus with a 46, X,Y,-D + t(DqGq) karyotype. Sex determination for X-linked anomalies resulted in detection of 2 Duchenne's muscular dystrophy, 1 hemophilia, 1 Norrie's syndrome, and 1 Pelizaeus-Merzbacher's syndrome.^ieng