Prenatal diagnosis of the duplication 17p11.2 associated with Potocki-Lupski syndrome in a foetus presenting with mildly dysmorphic features.

Duplication 17p11.2 (Potocki-Lupski syndrome (PTLS) MIM# 610883) is a genomic disorder with an estimated incidence of 1 in 25,000 births. As for other genomic disorders this duplication is typically de novo and is not associated with advanced maternal age or advanced paternal age. Herein we describe a prenatal diagnosis of duplication 17p11.2. This diagnosis was not suspected as the prenatal ultrasound findings were non-specific; however, BACs-on-Beads™ technology and array comparative genomic hybridization (aCGH) confirmed the common ∼3.7 Mb duplication. Evaluation of the foetus following termination of pregnancy revealed mildly dysmorphic features as well as congenital anomalies not previously reported in PTLS, specifically left pulmonary isomerism, an abnormally positioned left coronary orifice and nodular cerebellar heterotopia. This report exemplifies the utility of prenatal testing using new genomic technologies even when there are no multiple anomalies on foetal ultrasound. This report also exemplifies the utility of foetal autopsy in the identification of "occult" congenital anomalies.

Genotype-phenotype correlations in fetuses and neonates with autosomal recessive polycystic kidney disease.

The prognosis of autosomal recessive polycystic kidney disease is known to correlate with genotype. The presence of two truncating mutations in the PKHD1 gene encoding the fibrocystin protein is associated with neonatal death while patients who survive have at least one missense mutation. To determine relationships between genotype and renal and hepatic abnormalities we correlated the severity of renal and hepatic histological lesions to the type of PKHD1 mutations in 54 fetuses (medical pregnancy termination) and 20 neonates who died shortly after birth. Within this cohort, 55.5% of the mutations truncated fibrocystin. The severity of cortical collecting duct dilatations, cortical tubule and glomerular lesions, and renal cortical and hepatic portal fibrosis increased with gestational age. Severe genotypes, defined by two truncating mutations, were more frequent in patients of less than 30 weeks gestation compared to older fetuses and neonates. When adjusted to gestational age, the extension of collecting duct dilatation into the cortex and cortical tubule lesions, but not portal fibrosis, was more prevalent in patients with severe than in those with a non-severe genotype. Our results show the presence of two truncating mutations of the PKHD1 gene is associated with the most severe renal forms of prenatally detected autosomal recessive polycystic kidney disease. Their absence, however, does not guarantee survival to the neonatal period.

Refining the clinicopathological pattern of cerebral proliferative glomeruloid vasculopathy (Fowler syndrome): report of 16 fetal cases.

Cerebral proliferative glomeruloid vasculopathy (PGV) is a severe disorder of brain angiogenesis, resulting in abnormally thickened and aberrant perforating vessels, forming glomeruloids with inclusion-bearing endothelial cells. This peculiar vascular malformation was delineated by Fowler in 1972 as a stereotyped lethal fetal phenotype associating hydranencephaly-hydrocephaly with limb deformities, called Fowler syndrome (FS) or "proliferative vasculopathy and hydranencephaly-hydrocephaly" or "encephaloclastic proliferative vasculopathy" (OMIM#225790). In PGV, the disruptive impact of vascular malformation on the developing central nervous system (CNS) is now well admitted. However, molecular mechanisms of abnormal angiogenesis involving the CNS vasculature exclusively remain unknown, as no genes have been localized nor identified to date. We observed the pathognomonic FS vascular malformation in 16 fetuses, born to eight families, four consanguineous and four non-consanguineous. A diffuse form of PGV affecting the entire CNS and resulting in classical FS in 14 cases, can be contrasted to two cases with focal forms, confined to restricted territories of the CNS. Interestingly in PGV, immunohistological response to a marker of pericytes (SMA, Smooth in PGV Muscle Actin), was drastically reduced as compared to a match control. Our studies has expanded the description of FS to additional phenotypes, that could be called Fowler-like syndromes and suggest that the pathogenesis of PGV may be related to abnormal pericyte-dependent remodelling of the CNS vasculature, during CNS angiogenesis. Gene identification will determine the molecular basis of PGV and will help to know whether the Fowler-like phenotypes are due to the same underlying molecular mechanisms.

Embryology of neural tube defects: information provided by associated malformations.

OBJECTIVES: To get information about embryologic mechanisms of neural tube defects (NTD), by studying the associated malformations. METHODS: Eighty three cases of NTD, seen at the prenatal diagnosis unit of Rennes University Hospital (France) between May 1999 and December 2002, were retrospectively studied. Cases with chromosomal anomalies (5/83), cases without available karyotype or pathologic examination were excluded. 24 spina bifida, and 27 cephalic forms (anencephalies, exencephalies, and encephaloceles) were thus analyzed. RESULTS: Only 22/51 cases (43%) were strictly isolated NTD. Anomalies of tissues arising from neural crests were noted in 8/51 fetuses (16%), midline or lateralization anomalies in 12/51 (24%), and anomalies of mesoblastic tissues in 17/51 (33%). An already known syndrome was found in 4/51 cases (8%). CONCLUSION: NDT are more extensive congenital damages that would suggest the restrictive terminology. That prompts to assess cautiously prenatal diagnosis of NTD, and to get detailed pathological examination after termination of pregnancy.

Flow cytometric analysis of in vivo polyamine deprivation in Lewis lung carcinoma (3LL) cells using the monoclonal antibody SPM8-2.

It has previously been shown that the monoclonal antibody SPM8-2 recognizes free spermine and spermidine as well as polyamines bound by an amide bond. In the present work it is demonstrated that this antibody also interacts with spermidine, spermine, and to a lesser extent N1- and N8-acetyl spermidine in an ELISA test where the polyamines are bound by reaction with formaldehyde. 3LL Lewis lung carcinoma cells from tumor-grafted mice were labeled with fluorescein-conjugated monoclonal antibody SPM8-2 and analyzed by flow cytometry. Both viable cells and formaldehyde-fixed and subsequently permeabilized cells showed fluorescent staining. However, most polyamines present in the cells are not directly available for antibody binding. Treatment of fixed cells with DNase or RNase greatly increased fluorescent staining, suggesting that some polyamines are co-localized with DNA and RNA. Antibody labeling of the cells was prevented by addition of free spermine. 3LL cells from tumors of mice treated by a polyamine depleting regimen had decreased intracellular spermidine levels and bound less antibody when compared to untreated controls. After digestion with RNase, the cells from treated mice bound considerably less fluorescent antibody than tumor cells from untreated mice, while their RNA content was similar. In contrast, fluorescent staining after DNase digestion was only slightly affected by the treatment with a polyamine depleting regimen. This suggests that the pools of polyamines which are co-localized with RNA are depleted more readily than those associated with DNA. Since only a small proportion of the intracellular polyamines is accessible to the bulky antibodies, treatment with hydrolytic enzymes (DNase, RNase) is necessary to reveal specific compartments of the polyamines and to demonstrate qualitative and semi-quantitative differences of their distribution within cells.

Necrotizing sarcoid granulomatosis with and without extrapulmonary involvement.

Three cases of necrotizing sarcoid granulomatosis (NSG) are reported. All 3 patients had pulmonary lesions; one of them had additional extrapulmonary lesions which were ophthalmologic (dacryoadenitis) and digestive (ulcerative colitis). This patient was followed for 5 years and developed several respiratory, ophthalmologic and digestive recurrences. In 2 cases the diagnosis of NSG had been initially overlooked and the authors emphasize the difficulties of this histologic diagnosis in terms of the differential diagnosis with other necrotic and granulomatous pulmonary diseases such as tuberculosis and Wegener's granulomatosis. They stress the possibility of extrapulmonary lesions in NSG and discuss the relationship between NSG and sarcoidosis.