Prevalence of respiratory syncytial virus infection in Italian infants hospitalized for acute lower respiratory tract infections, and association between respiratory syncytial virus infection risk factors and disease severity.

This study was designed to collect data on the prevalence of respiratory syncytial virus (RSV) infection in Italy in infants hospitalized for lower respiratory tract infections, and to evaluate which of the recognized risk factors might be associated with disease severity. Thirty-two centers throughout Italy participated in the study. Over a 6-month period (November 1,1999 to April 30, 2000), we evaluated all children < 2 years of age hospitalized for lower respiratory tract infections. All subjects were tested for RSV within 24 hr of hospitalization by using an immuno-enzymatic diagnostic test (Abbott Testpack, RSV). Logistic regression was used to identify the factors that might be associated with more severe disease or could increase the likelihood of RSV positivity in hospitalized infants. Out of a total of 1,232 children enrolled, 40.6% were found to be RSV-positive (RSV+). The peak of the RSV epidemic occurred in February, while the lowest prevalence of RSV positivity was seen in November (P < 0.05). A high proportion of study subjects had low birth weight and low gestational age. The clinical diagnosis at hospitalization was bronchiolitis in 66.7%, pneumonia in 15.3%, and wheezy bronchitis in 18.1%. In the bronchiolitis group, a higher prevalence of RSV+ was found in patients with gestational age or= 36 weeks (P < 0.04). No differences were found in the proportion of RSV+ patients in the three gestational age subgroups with pneumonia and wheezy bronchitis (P > 0.05, each comparison). Independent of the clinical diagnosis at admission, RSV infection was associated with more severe respiratory impairment. Environmental smoke exposure was higher in subjects with bronchiolitis than in those with wheezy bronchitis (P < 0.04), and RSV+ was positively related with the birth order (P < 0.05). The presence of older siblings and birth order plays an important role in RSV infection. The collected data show that, in Italy, RSV is an important cause of lower respiratory tract infection in infants. Gestational age, birth order, birth weight, and exposure to tobacco smoke affected the prevalence and severity of RSV-related lower respiratory tract disease.

Monocyte adhesion to activated aortic endothelium: role of L-selectin and heparan sulfate proteoglycans.

This study examines the role of L-selectin in monocyte adhesion to arterial endothelium, a key pathogenic event of atherosclerosis. Using a nonstatic (rotation) adhesion assay, we observed that monocyte binding to bovine aortic endothelium at 4 degrees C increased four to nine times upon endothelium activation with tumor necrosis factor (TNF)-alpha. mAb-blocking experiments demonstrated that L-selectin mediates a major part (64 +/- 18%) of monocyte attachment. Videomicroscopy experiments performed under flow indicated that monocytes abruptly halted on 8-h TNF-alpha-activated aortic endothelium, approximately 80% of monocyte attachment being mediated by L-selectin. Flow cytometric studies with a L-selectin/IgM heavy chain chimeric protein showed calcium-dependent L-selectin binding to cytokine-activated and, unexpectedly, unactivated aortic cells. Soluble L-selectin binding was completely inhibited by anti-L-selectin mAb or by aortic cell exposure to trypsin. Experiments with cycloheximide, chlorate, or neuraminidase showed that protein synthesis and sulfate groups, but not sialic acid residues, were essential for L-selectin counterreceptor function. Moreover, heparin lyases partially inhibited soluble L-selectin binding to cytokine-activated aortic cells, whereas a stronger inhibition was seen with unstimulated endothelial cells, suggesting that cytokine activation could induce the expression of additional ligand(s) for L-selectin, distinct from heparan sulfate proteoglycans. Under flow, endothelial cell treatment with heparinase inhibited by approximately 80% monocyte attachment to TNF-alpha-activated aortic endothelium, indicating a major role for heparan sulfate proteoglycans in monocyte-endothelial interactions. Thus, L-selectin mediates monocyte attachment to activated aortic endothelium, and heparan sulfate proteoglycans serve as arterial ligands for monocyte L-selectin.

P-selectin glycoprotein ligand 1 is a ligand for L-selectin on neutrophils, monocytes, and CD34+ hematopoietic progenitor cells.

Selectins play a critical role in initiating leukocyte binding to vascular endothelium. In addition, in vitro experiments have shown that neutrophils use L-selectin to roll on adherent neutrophils, suggesting that they express a nonvascular L-selectin ligand. Using a L-selectin/IgM heavy chain (mu) chimeric protein as an immunocytological probe, we show here that L-selectin can bind to neutrophils, monocytes, CD34+ hematopoietic progenitors, and HL-60 and KG-1 myeloid cells. The interaction between L-selectin and leukocytes was protease sensitive and calcium dependent, and abolished by cell treatment with neuraminidase, chlorate, or O-sialoglycoprotein endopeptidase. These results revealed common features between leukocyte L-selectin ligand and the mucin-like P-selectin glycoprotein ligand 1 (PSGL-1), which mediates neutrophil rolling on P- and E-selectin. The possibility that PSGL-1 could be a ligand for L-selectin was further supported by the ability of P-selectin/mu chimera to inhibit L-selectin/mu binding to leukocytes and by the complete inhibition of both selectin interactions with myeloid cells treated with mocarhagin, a cobra venom metalloproteinase that cleaves the amino terminus of PSGL-1 at Tyr-51. Finally, the abrogation of L- and P-selectin binding to myeloid cells treated with a polyclonal antibody, raised against a peptide corresponding to the amino acid residues 42-56 of PSGL-1, indicated that L- and P-selectin interact with a domain located at the amino-terminal end of PSGL-1. The ability of the anti-PSGL-1 mAb PL-1 to inhibit L- and P-selectin binding to KG-1 cells further supported that possibility. Thus, apart from being involved in neutrophil rolling on P- and E-selectin, PSGL-1 also plays a critical role in mediating neutrophil attachment to adherent neutrophils. Interaction between L-selectin and PSGL-1 may be of major importance for increasing leukocyte recruitment at inflammatory sites.

Ulnar ray defect in an infant with a 6q21;7q31.2 translocation: further evidence for the existence of a limb defect gene in 6q21.

Ectrodactyly is a developmental defect of the distal limbs characterized by marked clinical variability and genetic heterogeneity, also reflected in the observation of different chromosome abnormalities non randomly associated with longitudinal postaxial limb deficiencies. The one most frequently found in patients with split hand-split foot (SHSF) involves chromosome band 7q22. Recently, structural anomalies of chromosome 6q21 have been reported in 2 unrelated patients with SHSF, suggesting that this region may also contain genes responsible for limb development [Braverman et al., 1993. Am J Hum Genet, suppl 53: 410; Viljoen and Smart, 1993. Clin Dysmorph 2: 274-277]. We report on a third patient who had a de novo, apparently balanced t(6;7)(q21;q31.2) translocation and bilateral ulnar aplasia with postaxial oligodactyly. In spite of the different phenotypic effects observed in these 3 patients, we consider our case as further evidence that genes in 6q21 may play a role in distal limb development.

New syndrome: autosomal dominant microcephaly and radio-ulnar synostosis.

To date, the combination of microcephaly and radio-ulnar synostosis has not been recognized as a distinct clinical and genetic entity. We report on 4 familial cases with this previously undescribed combination of defects, showing autosomal dominant inheritance (Fig. 1).

VATER/VACTERL association: clinical variability and expanding phenotype including laryngeal stenosis.

Vertebral abnormalities and anorectal and tracheoesophageal defects are the main manifestations in the VATER/VACTERL association. Radial defects vary from radial aplasia to thumb duplication. Heart and renal defects are reported with lower frequency. Additional malformations, such as the laryngeal stenosis described in the present patient, may expand the phenotype of the association. The wide spectrum of congenital abnormalities confirms the high clinical variability of VATER/VACTERL association which seems to be due to a disruption of blastogenesis.

Thanatophoric dysplasia in monozygotic twins discordant for cloverleaf skull: prenatal diagnosis, clinical and pathological findings.

We present male monozygotic twins with thanatophoric dysplasia (TD) type I concordant for long bone abnormalities and discordant for cloverleaf skull. The twins were the product of the second pregnancy of unrelated parents, with advanced paternal age. Prenatal diagnosis and postmortem examination showed severe rhizomelic shortness of limbs, bowing of the long bones with "telephone-receiver" femora in both twins, and cloverleaf skull and hydrocephalus in one of them. It is now accepted that most of cases of TD, such as in the present report, represent an autosomal dominant mutation with a high new mutations rate.

Spondylo-costal dysostosis in two siblings.

Two new cases of Spondylo-Costal Dysostosis (SCD) are reported in two siblings with strikingly similar skeletal abnormalities. Parental consanguinity documents in this family an autosomal recessive inheritance of trait. Clinical variability of SCD is discussed on the basis of clinical and radiological features. Its genetic heterogeneity is pointed out even considering the occurrence of cases with autosomal dominant as well as recessive inheritance.

[Role of diagnostic imaging in Rubinstein-Taybi syndrome. Personal experience with 8 cases]. / Ruolo della diagnostica per immagini nella sindrome di Rubinstein-Taybi. Esperienza personale su 8 casi.

Both etiology and pathogenesis of Rubinstein-Taybi syndrome (RTS) are still questionable, even though a genetic factor seems to be certain. A typical face, psychomotor delay, and thumb and halluces abnormalities (big, prevalently short, and often "spoon-like" toes) are the main characteristic patterns of RTS. Eight subjects (4 male and 3 female children aged 26 days-7 years, and a 31-year-old woman, mother of 1 of the affected children) with different signs of RTS were studied over the last 3 years. The results are here reported, with a special emphasis on malformations detected with conventional radiography (Rx), Computerized Tomography (CT), and ultrasound (US). Evaluated parameters were thumbs and halluces (Rx), bone age and skeleton (Rx), cranium (Rx) and encephalon (US, CT), cryptorchidism (US, CT), and urological (Rx, US) and cardiovascular (US) systems. A typical face and psychomotor delay were found in all cases, while thumb and halluces abnormalities were observed only in 6 cases. Among several clinical signs of RTS, we found: severe (less than 3rd centile) bone maturation delay in 4 cases; skull volume reduction (less than 50th centile) in 3 subjects and microcrania in 4; skeletal abnormalities in 7 cases (5 of them positive for bilateral coxofemoral abnormalities); urinary tract (4 cases) and cardiovascular (3 cases) malformations; and cryptorchidism in 3 of 4 males. A case was diagnosed during neonatal period (within the first month of life); it was a rare case associated with a variant form of Dandy-Walker anomaly; semiologic similarities were observed between mother and daughter patients. X-rays, US and CT rarely play an important role in the diagnosis of RTS, considering the several clinical signs, mainly the face, affecting the patients. However, diagnostic imaging techniques help diagnose hidden malformations and confirm and integrate clinical signs.

Kabuki make-up (Niikawa-Kuroki) syndrome: clinical and radiological observations in two Sicilian children.

The Authors describe two patients aged 5 and 8, a female and a male, affected by a condition of polymalformations known as Kabuki make-up or Niikawa-Kuroki syndrome, having a neonatal incidence of 1:32,000 in Japan. There are two hypothesis about the apparent rarity of the syndrome in the rest of the world, including the Asian Continent: the first is that it exists, but is infrequently recognized outside Japan and the second is that it is really more frequent in those parts of the world, where ethnic exchanges are uncommon, as it happens in Japan.

Holoprosencephaly: examples of clinical variability and etiologic heterogeneity.

Clinical variability and causal heterogeneity of holoprosencephaly is discussed in relation to several newborn infants with cyclopia (cases 4,5,6), cebocephaly (cases 2,3), and premaxillary agenesis (case 1). In subjects with holoprosencephaly, the presence of multiple malformations is an indicator of concomitant chromosome aberrations, as in present case 1 (Down syndrome) and case 3 (trisomy 13). Cases 5 and 6 are two monozygotic twins with the same type of cyclopia and alobar holoprosencephaly recognized by prenatal ultrasonography. The diagnostic importance of ultrasonographic, cytogenetic, and pathological studies is pointed out in view of etiologic evaluation, genetic counseling, and prevention of holoprosencephaly.

[Ultrasonics in the diagnosis and monitoring of cryptorchism in children]. / L'ecotomografia nella diagnosi e nel monitoraggio del criptorchidismo infantile.

The diagnostic reliability of US was investigated in the study of cryptorchidism during a 9-month clinical and US trial performed on 52 children (mean age 4.3 years). Cryptorchidism was unilateral in 44 cases (24 on the left side and 20 on the right side), and bilateral in 8 cases. Of 60 cryptorchid testes, 53--belonging to 45 of 52 patients--were located in the inguinal region (18 along the canal, 20 at the external ring, and 15 at the internal one); the others 7--belonging to the remaining 7 subjects--were found in an extra-inguinal region (4 in paravesical location and 3 in the inferior abdomen). US confirmed 29 undescended testes with clinical evidence in the inguinal region and identified, in the same area, 24 other testes which had been missed at clinical examination. In addition, US provided useful information as to both structure and volumetry of the gonads. On the other hand, US failed to provide reliable diagnostic results in the rare cases of pelvic and abdominal cryptorchidism, where precise testes localization was achieved by CT. US is the diagnostic technique of choice in the study of cryptorchidism (after clinical examination): the method is non-invasive and simple, has low cost and its use is widespread; moreover, US does not administer ionizing radiations. According to our experience, US had 88.3% diagnostic sensitivity as for undescended testes (53 of 60), and 100% specificity. In addition, US monitoring allowed clinical efficacy of therapeutic trials to be verified in 25 patients (17 sensitive to therapy): 16 of them were treated with human Chorionic Gonadotropin (hCG) and 9 with Luteinizing Hormone-Releasing Hormone (LH-RH).

Cervico-oculo-acusticus (Wildervanck's) syndrome: a clinical variant of Klippel-Feil sequence?

A 7-year-old female child with phenotype of Cervico-Oculo-Acousticus (Wildervanck's) syndrome is presented. In addition to fusion of multiple cervical vertebrae with short neck, abducens nerve palsy and deafness, the child showed severe growth and bone delay, renal abnormalities and slight mental retardation. The presence of such malformations seems to suggest that Wildervanck's syndrome is a clinical variant of Klippel-Feil sequence. Both conditions usually have sporadic occurrence with female prevalence, more consistent for cervico-oculo-acousticus syndrome. The possibility of dominant inheritance has been postulated for both, autosomal for Klippel-Feil, autosomal or X-linked with lethality in hemizygous for Wildervank's one. An environmental etiology, due to a vascular disruption sequence during embryonic development, has been noted in Klippel-Feil, as in Moebius and Poland sequences. A combination of defects (Klippel-Feil and Moebius) could induce the more complex phenotype observed in Wildervanck's syndrome.

gp33-38, an early human T cell activation antigen.

We describe an activation Ag Me14/D12 that appears early after T cell activation and is absent in resting T lymphocytes. Me14/D12 is a nondisulfide-linked heterodimeric structure containing two polypeptide chains of 33,000 and 38,000 Da. The expression of Me14/D12 on resting T lymphocytes can be induced by different activation stimuli such as the lectins PHA and Con A, the phorbol ester PMA, and anti-CD3 mAb. The induction of mRNA for Me14/D12 (gp33-38) in PHA-activated T lymphocytes precedes that of IL-2R gene transcripts by more than 20 h. Me14/D12 mRNA was detectable as early as 2 h after the onset of activation and mRNA for the IL-2R only after 24 h. The surface expression of Me14/D12 was detectable between 12 and 24 h after activation and was maximal between 24 and 48 h. Several T leukemia cell lines express the Me14/D12 Ag. On Me14/D12- cell lines, PMA and IFN-gamma induced surface expression of Me14/D12. Once Me14/D12 Ag were expressed on Jurkat cells after stimulation with either PMA or IFN-gamma, the binding of mAb Me14/D12 induced the production of significant amounts of IL-2 and of Ca2+ mobilization from internal stores. Comparative biochemical studies clearly demonstrate that Me14/D12 (gp33-38) is different from the CD69 molecular complex defined by mAb MLR3 and AIM.

[A morphologic study of extrapulmonary multisystemic lesions in neonatal respiratory syndrome]. / Studio morfologico delle lesioni multisistemiche extrapolmonari nella sindrome respiratoria neonatale.

Extra-pulmonary multisystemic lesions in respiratory syndrome of infants. A morphological study. This paper concerns the description of extra-pulmonary multisystemic lesions in 40 infants died because of "Respiratory Distress Syndrome". In infants with intra-cranial hemorrhage the association with cardiac infarct lesions makes possible a cause-effect relationship mediated by hypovolemic phenomena and/or by catecholamine activity.

Growth charts of Down syndrome in Sicily: evaluation of 382 children 0-14 years of age.

We present the results of a study performed on a Sicilian population of children with Down syndrome (DS) 0-14 years of age, observed between 1977 and 1988. Data from the present report concern 382 subjects with nonmosaic 21 trisomy, including 239 males (62.6%) and 143 females (37.4%). We excluded all DS children observed in the same period with associated pathology (congenital heart defects, gastrointestinal malformations, malabsorption, hypothyroidism, and thalassemia). Overall, 1,464 measurements were performed of length or height, weight, and head circumference. Means and standard deviation (SD) were calculated for all of these parameters. Our data confirm a trend toward a progressive improvement of growth in children with DS, as shown in other recent reports. The purpose of this study was also to create a "normal growth pattern" useful to evaluate DS children and also to diagnose early pathologic conditions affecting growth, such as autoimmune diseases.

Genetic factors of recurrent abortions.

A review of main genetic factors involved in pathogenesis of recurrent abortion is presented. The prevalence of chromosomal abnormalities in spontaneous abortions and the role of parental abnormalities of karyotype is pointed out, also in relation to many recent studies. The result of 354 karyotypes performed on couples with spontaneous abortion are presented; the prevalence of chromosomal abnormalities resulted 4.2%, with 73% of translocations, either reciprocal (40%) or robertsonian (33%), and 27% of inversions. The low number of minor abnormalities (0.8%) seems to confirm their poor clinical significance.