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Little is known about the effects of immunosuppression on patients with hereditary nonpolyposis colorectal cancer (HNPCC). We describe a kidney transplant recipient with unrecognized Muir-Torre syndrome in whom the administration of a tacrolimus-based regimen led to the eruption of multiple sebaceous tumors. The patient was later found to harbor an MSH2 mutation. Switching to a sirolimus-based regimen resulted in arrest of the disease. When the patient was switched back to tacrolimus, new facial lesions rapidly appeared. Switching again to sirolimus resulted again in halting the appearance of new lesions. This finding is in line with the known antiangiogenic activity of sirolimus and reports on the regression of cutaneous Kaposi's sarcoma in kidney transplant recipients switched from another immunosuppressive regimen to sirolimus. Further studies on the potential use of sirolimus for the treatment of de novo tumors in immunosuppressed kidney transplant recipients with HNPCC are warranted.

The clinical significance of mosaicism trisomy 20 detected prenatally following amniocentesis remains uncertain, due to the rarity of liveborn cases with inconsistent clinical findings, the short postnatal follow-up, and failure in evaluating other fetal tissues for the presence of the trisomy. We report on a 15 month-old 46,XX chromosome constitution in white blood cells, while skin fibroblasts demonstrated trisomy 20 mosaicism (54%) by fluorescence in situ hybridization (FISH) analysis. Clinical examination of the baby showed only minor phenotypic signs (bilateral epicanthal folds, delayed closure of fontanel with no other gross anomalies), but demonstrated a considerable developmental delay in gross and fine motor skills along with hypotonicity. This is the second oldest described liveborn with trisomy 20 mosaicism confirmed in skin fibroblasts. This cytogenetic aberration along with her developmental delay suggests that the two findings are related and that aberration affects various fetal tissues and is not confined to extra-embryonic tissue as suggested previously. Yet, an undiagnosed condition may be the cause of the child's developmental delay. Based on this case and following a review of the literature we suggest that when mosaic trisomy 20 is identified in amniocytes, further evaluation is required. Cord blood should be analyzed preferably by FISH. During counseling the parents should be advised of an additional risk, such as developmental delay, even when fetal cord karyotype and detailed ultrasonic scan are normal.

This study was undertaken in an attempt to determine the significance of elevated maternal serum human chorionic gonadotropin (MShCG), in the presence of an otherwise normal screen with respect to fetal malformations, chromosomal aberrations, and pregnancy outcome. Targeted ultrasound findings and perinatal outcome of 298 women in whom serum hCG was > or = 2.5 MOM and who were screen-negative for Down syndrome (the study group) were compared with a control group of 229 women in whom serum hCG as well as the other parameters were within the normal range. Genetic amniocentesis was performed in 125 women from the study group. Ultrasonically detected malformations were significantly more frequent among the study group (12 vs. 1, P = 0.01). Pregnancy complications were similar in the two groups, with the exception of pre-eclampsia-toxaemia, which was significantly more frequent in the study group (5 vs. 0, P = 0.02). There was one case of an abnormal karyotype (47,XXY). Although genetic amniocentesis does not appear warranted, isolated elevated MShCG levels during the second trimester screening was associated with an increased risk of fetal anomalies detected by ultrasound and of toxaemia of pregnancy.

Cytogenetic and fluorescent in situ hybridization (FISH) studies were performed on several formalin-fixed tissues obtained from four fetuses diagnosed at amniocentesis as 45,XO-Turner syndrome. Three of the four were phenotypically normal and one had malformations. The three phenotypically normal cases were found to have an additional normal cell line, which may explain their ability to survive, at least to the time of pregnancy termination well into the second trimester. The abnormal 45,XO fetus was not found to be mosaic in all of the tissues examined. In 45,XO cases in which no malformation is detected, the possibility of mosaicism should be raised and thus the counselling should be modified accordingly.

Incorporation of maternal serum unconjugated estriol into the calculation of risk may increase the yield of serum screening performed during pregnancy for detection of fetal chromosomal and structural anomalies. The differential diagnosis of very low and undetectable levels of unconjugated estriol in maternal serum is discussed, with special emphasis on the prenatal diagnosis of X-linked ichthyosis. The prenatal detection of these findings dictates skilled genetic counseling, targeted sonographic evaluation and examination of fetal karyotype and fetal cDNA for Xp 22.32 with amniotic fluid levels of cortisol, STS, and ASC.

Five cases of supernumerary marker chromosomes were identified in prenatal diagnosis as derived from chromosomes 18, X, and Y. One unexpected finding was in a case where the PCR was positive for the SRY gene while fluorescence in situ hybridization was positive for two X centromeres. In another case with an X derived supernumerary marker the newborn was phenotypically normal. Two women with fetal mar(18) and mar(Xp) decided to terminate the pregnancy. The fifth pregnancy had a karyotype of 46,XX,-15,+der(15)t(Y:15)(q11,23;p13). A phenotypically normal girl was born at term.

Objective A study was conducted to evaluate the sensitivity of combining a second trimester triple test and targeted ultrasound in order to detect Down syndrome in women undergoing amniocentesis over 35 years of age. Methods Women over 35 years of age underwent a triple test and an ultrasound examination for chromosomal markers immediately prior to genetic amniocentesis. Results One thousand and six women were examined. Four hundred and thirty seven were triple test-positive and in 195 cases ultrasonographic abnormalities were observed. Thirteen had Down syndrome and eight had other chromosomal abnormalities. All women with Down syndrome babies were triple test-positive and seven also had ultrasonographic markers. Three of eight women who had babies with chromosomal aberrations other then Down syndrome were also triple test-positive. Conclusions The use of the triple test as a screening tool in our population would reduce the number of amniocenteses by 60%, while no cases of Down syndrome would be missed. Ultrasonographic markers have added little to this population. Three non-Down syndrome chromosomal abnormalities and two Down syndrome mosaic cases would be missed by this approach. Copyright © 2002 John Wiley & Sons, Ltd.

We evaluated the feasibility of retrospective genetic testing for numerical chromosomal aberrations by applying the FISH technique to formalin-fixed fetal tissue. Fetal tissue from 10 old cases with known aneuploidy and from 13 cases with known fetal malformations, were tested with specific DNA probes for pericentromeric repeat regions of chromosomes 13/21, 18, X and Y. FISH diagnosis concurred with karyotype in all nine cases with sufficient cells. Numerical aberration was diagnosed in six out of 13 cases with fetal malformations.

Washed cells, from ascitic fluid, which contained predominantly polymorphonuclear leucocytes from casein treated donor mice, induced accelerated amyloid formation in untreated syngeneic recipient animals. A similar transfer model, with lymph node cell suspension, was ineffective. Amyloidogenesis was completely blocked by colchicine treatment of the donors while treatment of the recipients had no effect. A casein induced amyloidogenic stimulus was transferred from nude C3H mice to their normal litter-mates. When the order was reversed, no amyloidosis occurred in the nude recipients. These experiments indicate the possible involvement of two cells in the biphasic process of casein induced murine amyloid formation: the polymorphonuclear leucocyte in the first phase and the T lymphocyte in the second.

Dimethyl sulfoxide was administered intravenously for 60 days to twenty mice with casein-induced amyloidosis. Partial or total disappearance of amyloid deposits occurred in all treated animals. The urine of these animals contained a substance from which amyloid fibrils could be synthesized. A control group of mice with casein-induced amyloidosis given saline injections showed massive amyloid deposition in the liver and in the spleen at the end of the experiment. Neither the urine of these mice nor the urine of normal control mice treated with dimethyl sulfoxide contained substances from which amyloid fibrils could be synthesized. It is our assumption that dimethyl sulfoxide treatment of mice with amyloidosis resulted in a break up of amyloid fibres into small subunits which were excreted in the urine.

In vitro experiments have shown that the amyloid degrading activity of amyloidotic sera could be restored by ascorbic acid, citric acid and by EDTA. It was therefore decided to test the influence of Vitamin C on experimental murine amyloidosis. Amyloidosis was induced during 14 days in three groups of 60 animals each. The first group received Vitamin C in the drinking water, as 3.5% solution, throughout the entire experimental period. Vitamin C was given to the second group after the induction of amyloidosis, while the control group received water alone. On the tenth, 17th, and 20th post induction days, 15 mice of each group were sacrificed. Their spleens were examined for the presence of amyloid. On the 17th day no amyloid was found in nine mice (out of 15) of the first group and in eight of the second. Small deposits were observed in five and three animals respectively. However, in the control groups giant deposits of amyloid were found in ten out of 15 animals. Amyloid degrading activity (ADA) of murine serum was examined in untreated, amyloidotic and Vitamin C treated animals. In healthy animals the ADA is unaffected by Vitamin C. In amyloidotic mice which have very low ADA initially, the addition of Vitamin C significantly increases the ADA. These results may possibly indicate that the in vitro effect of Vitamin C on amyloidotic sera is also expressed in an in vivo experimental model.

The natural clinical course of four patients with systemic amyloidosis was favourably altered by continuous colchicine therapy. One patient had primary amyloidosis, and the other three suffered from amyloidosis of familial Mediterranean fever. All had a nephrotic syndrome, and one showed features of intestinal malabsorption. The institution of colchicine therapy was followed by a gradual remission of the nephrotic syndrome, a rise of serum albumin to normal values, a slight improvement of renal function, and regression of the intestinal malabsorption. This pattern has remained steady during an observation period of 30 months.