Changing trends in patient decisions concerning genetic amniocentesis.

OBJECTIVE: This study was undertaken to determine whether there was a change in patient decisions concerning genetic amniocentesis during the period 1995-1998. STUDY DESIGN: All patients referred for genetic counseling because of advanced maternal age, abnormal serum triple-screen results, or ultrasonographic abnormalities between January and March 1995 and between January and March 1998 were evaluated through a retrospective chart review. Patient characteristics included age, race, and gestational age. Group 1 consisted of patients from 1995. Group 2 consisted of patients from 1998. Data on patient decisions concerning amniocentesis before and after genetic counseling and ultrasonographic examination were compared in each group. Groups 1 and 2 were then compared with respect to decisions before and after genetic counseling and ultrasonographic evaluation. RESULTS: A total of 112 patients were studied. Group 1 consisted of 53 patients and group 2 consisted of 59 patients. When the groups were compared, no differences in age, race, or gestational age were noted. In group 1, before counseling, 18 of 53 patients desired genetic testing, compared with 44 of 53 after counseling (P =.02). In group 2, before counseling, 4 of 59 patients desired genetic testing, compared with 15 of 59 after counseling (P =.01). A significantly greater number of patients in group 1 than in group 2 desired genetic testing both before counseling (n = 18/53 vs n = 4/59; P =.01) and after counseling (n = 44/53 vs n = 15/59; P =.01). CONCLUSION: Fewer patients at risk for Down syndrome in 1998 than in 1995 desired amniocentesis both before and after genetic counseling and ultrasonographic examination.

Plasmapheresis in the treatment of steroid-resistant focal segmental glomerulosclerosis in native kidneys.

A circulating glomerular capillary albumin permeability factor (P(alb)) has been implicated in the pathogenesis of focal segmental glomerulosclerosis (FSGS), which recurs in transplanted kidneys. Plasmapheresis for recurrent FSGS may reduce proteinuria and stabilize renal function if instituted early. We performed six plasmapheresis treatments over 2 weeks in eight patients with a history of steroid-resistant idiopathic FSGS in native kidneys for an average of 12 +/- 2.3 months to determine whether treatment would decrease proteinuria or stabilize renal function. P(alb) was measured before and after plasmapheresis, and patients were followed-up for a mean of 29 +/- 4 months after the development of clinical symptoms. Proteinuria decreased in two of eight treated patients, although only transiently in one of the two. P(alb) improved in one of the two responding patients. Both patients with an improvement in proteinuria had stable renal function at last follow-up. In six of eight patients, there was no improvement in proteinuria despite an improvement in P(alb) (P < 0.0001) after plasmapheresis. At last follow-up, renal function was stable in two of the six nonresponding patients, and four of the six had significant progression of renal disease or were receiving dialysis treatments. These studies suggest that plasmapheresis may diminish proteinuria and stabilize renal function in a small minority of patients with steroid-resistant idiopathic FSGS. However, the lack of a relationship between the removal of the circulating permeability factor and the development of remission in these patients suggests that local factors associated with advanced renal injury or systemic factors unrelated to glomerular permeability play a significant role in determining proteinuria at this late stage of the disease.

Apoptosis in mesangial cells induced by ionizing radiation and cytotoxic drugs.

Mesangial proliferation contributes to the pathogenesis of many forms of glomerulonephritis. To evaluate the role of apoptosis on the pharmacologic effects of cytotoxic drugs and ionizing radiation, we studied their effects on cultured rat mesangial cells (MC), whose apoptotic response to these drugs is unknown. Mesangial cells were cultured with or without stimuli to induce apoptosis and were harvested at 24 and 48 hours. MC morphology was examined by light microscopy, in situ end labeling technique using terminal deoxy-transferase (TUNEL) and by electrophoresis of extracted total cellular DNA. MCs exposed to cytotoxic drugs or irradiation demonstrated statistically significant increases in apoptotic cells identified by light microscopy. DNA fragmentation of apoptotic cells was also visualized as characteristic staining by the TUNEL method and statistically significant increases in apoptotic cell number in cells exposed to cytotoxic drugs and irradiation were noted compared to control cultures. In general, the number of TUNEL positive cells was greater than that of morphologically apoptotic cells. DNA extracted from these cells also showed the characteristic ladder pattern of internucleosomal chromatin cleavage of 180 bp fragments on agarose gel electrophoresis. To further analyze whether MC apoptosis induced by these drugs alters the cell cycle, 3H-thymidine incorporation rates were measured in both the cell culture monolayer and in those cells shed into the supernatant when cultured with or without cyclophosphamide (N = 5). 3H-thymidine incorporation corrected for total cellular DNA showed a similar pattern in both control and cyclophosphamide treated groups, suggesting that cyclophosphamide did not alter the mesangial cell cycle. Considering that the dosage of the cytotoxic drugs utilized in these experiments in nearly the therapeutic plasma level in humans, these results suggest that cytotoxic drugs used to treat glomerular disease can induce apoptotic mesangial cell death and may operate in part via this mechanism.

Insulin-like growth factor-I and insulin-like growth factor-binding proteins in the nephrotic syndrome.

Similar to findings in the nephrotic syndrome in humans, rats with the doxorubicin-induced nephrotic syndrome (which resembles minimal change disease) have reduced serum levels of insulin-like growth factor-I (IGF-I). This is mainly caused by glomerular ultrafiltration of IGF-I-containing binding protein complexes, primarily of a molecular weight of approximately 50 kilodaltons, and urinary losses of the peptide. Despite urinary excretion of IGF-binding protein (IGFBP)-2, serum levels are increased more than twofold in the nephrotic syndrome compared with controls, because of increased synthesis of this binding protein by the liver. In contrast, the liver synthesis of IGFBP-3, the predominant binding protein in normal serum, is unchanged in the nephrotic syndrome. However, binding and serum levels of IGFBP-3 are reduced in nephrotic rat serum, apparently due to proteolytic degradation of IGFBP-3. The glomerular ultrafiltration of IGF-I, which leads to biologically significant IGF-I concentrations of about 1.35 nM in proximal tubule fluid, may have metabolic consequences, such as increased tubular phosphate absorption. Hypothetically, tubule fluid IGF-I may also contribute to progressive tubulointerstitial fibrosis which is sometimes present in protractive nephrotic glomerulopathies. The profound changes in the IGF-I/IGFBP system in the nephrotic syndrome may also contribute to systemic metabolic abnormalities and growth failure.

Insulin-like growth factor I induces mesangial proliferation and increases mRNA and secretion of collagen.

Insulin-like growth factor I (IGF-1) is a peptide growth factor that is synthesized in cultured mesangial cells and induces hyperplasia. We tested whether incubation with IGF-1 at concentrations of 7 nM, 70 nM, and 350 nM stimulates mesangial cell extracellular matrix mRNA and protein levels, and whether it influences mesangial cell growth. Mesangial cells incubated with IGF-1 demonstrated a statistically significant increase in procollagen alpha 1(I) (100 +/- 13% vs. 147 +/- 12%, 154 +/- 10%, and 173 +/- 21%) and alpha 1(IV) 100 +/- 9% vs. 112 +/- 9%, 125 +/- 8%, and 172 +/- 28%) mRNA. Furthermore, IGF-1 also stimulated a statistically significant increment in alpha 1(IV) mRNA in isolated glomeruli when measured by Northern hybridization and corroborated by in situ hybridization experiments. In addition, mesangial cells incubated with IGF-1 induced a statistically significant increase in both secreted and cell associated type I (secreted: 100 +/- 5% vs. 127 +/- 9%, 148 +/- 5%, 178 +/- 11%; and cell-associated: 100 +/- 19 vs. 132 +/- 17%, 198 +/- 24%, and 314 +/- 17%) and type IV (secreted: 100 +/- 19% vs. 138 +/- 11%, 192 +/- 17%, 379 +/- 16%, and cell-associated: 100 +/- 8% vs. 139 +/- 10%, 206 +/- 16%, 310 +/- 15%) collagen. Thus, mRNA and collagen levels increased in a dose dependent fashion after incubation with IGF-1. Furthermore, IGF-1 stimulated hyperplasia but not hypertrophy in this in vitro system. These data suggest that IGF-1 may contribute to glomerular sclerosis by increasing mesangial matrix production as well as proliferation.

Vaginal gram stain as an immediate detector of group B streptococci in selected obstetric patients.

During a 19-month period selective vaginal Gram stain and culturing were performed prospectively in all women admitted to the delivery room at risk for low birth weight delivery secondary to preterm premature rupture of the membranes or for prolonged membrane rupture secondary to term premature rupture of the membranes. Gram stain was performed and read immediately on admission. Cultures were also obtained simultaneously and sent for microbiologic evaluation. All women with Gram stains positive for gram-positive cocci were treated with intravenous ampicillin in the event of labor, unless vaginal culture results were already known and were negative for group B beta-hemolytic streptococcus. A total of 72 women had samples taken, and 30 (41.7%) were positive for gram-positive cocci. Nine (30%) of these were subsequently positive for group B beta-hemolytic streptococci by culture. There were no cultures positive for group B beta-hemolytic streptococci in the Gram stain-negative group. Gram stain sensitivity was 100% for predicting the presence of group B beta-hemolytic streptococci in the study population, and specificity was 66.7%. Selective vaginal Gram stain provides an effective and rapid screen for identifying the presence of group B beta-hemolytic streptococci and allows for immediate institution of appropriate antibiotic therapy in the event of onset of labor before the availability of culture results.