CD46 is a cellular receptor for human herpesvirus 6

Human herpesvirus 6 (HHV-6) is the etiologic agent of exanthema subitum, causes opportunistic infections in immunocompromised patients, and has been implicated in multiple sclerosis and in the progression of AIDS. Here, we show that the two major HHV-6 subgroups (A and B) use human CD46 as a cellular receptor. Downregulation of surface CD46 was documented during the course of HHV-6 infection. Both acute infection and cell fusion mediated by HHV-6 were specifically inhibited by a monoclonal antibody to CD46; fusion was also blocked by soluble CD46. Nonhuman cells that were resistant to HHV-6 fusion and entry became susceptible upon expression of recombinant human CD46. The use of a ubiquitous immunoregulatory receptor opens novel perspectives for understanding the tropism and pathogenicity of HHV-6.

Real-time quantitative PCR for human herpesvirus 6 DNA

The diagnosis of human herpesvirus 6 (HHV-6) infection represents a complex issue because the most widely used diagnostic tools, such as immunoglobulin G antibody titer determination and qualitative DNA PCR with blood cells, are unable to distinguish between latent (clinically silent) and active (often clinically relevant) infection. We have developed a new, highly sensitive, quantitative PCR assay for the accurate measurement of HHV-6 DNA in tissue-derived cell suspensions and body fluids. The test uses a 5' nuclease, fluorogenic assay combined with real-time detection of PCR amplification products with the ABI PRISM 7700 sequence detector system. The sensitivity of this method is equal to the sensitivity of a nested PCR protocol (lower detection limit, 1 viral genome equivalent/test) for both the A and the B HHV-6 subgroups and shows a wider dynamic range of detection (from 1 to 10(6) viral genome equivalents/test) and a higher degree of accuracy, repeatability, and reproducibility compared to those of a standard quantitative-competitive PCR assay developed with the same reference DNA molecule. The novel technique is versatile, showing the same sensitivity and dynamic range with viral DNA extracted from different fluids (i.e., culture medium or plasma) or from tissue-derived cell suspensions. Furthermore, by virtue of its high-throughput format, this method is well suited for large epidemiological surveys.

Impact of new treatments for respiratory failure on outcome of infants with congenital diaphragmatic hernia

Term and near-term newborn infants with congenital diaphragmatic hernia (CDH), symptomatic in the first 24 h of life or diagnosed antenatally, without other significant malformations were treated at our hospital with high-frequency oscillatory ventilation (HFOV) as a primary modality of ventilation and elective delay in surgical repair after a period of stabilisation. When unresponsive to HFOV, infants were treated with surfactant, inhaled nitric oxide (iNO) and extracorporeal membrane oxygenation (ECMO) to achieve pre-operative stabilisation. From October 1994 to August 1998, 28 newborn infants with CDH were managed with such treatment; mean birth weight was 3184 +/- 535 g and gestational age 38.5 +/- 1.85 weeks. Age at operation was 68 +/- 35 h. In 9 cases, large diaphragmatic defects required the use of a prosthetic patch (Gore-tex). HFOV was used for primary ventilation in inborn patients (n = 16); outborn infants (n = 12) were placed on HFOV at admittance. A total of 15 patients (53%) were stabilised using only HFOV. Bovine surfactant was administered in 12 infants and 4 responded. iNO was used in eight infants and five responded. ECMO was used in three outborn patients and one survived. Overall, out of 28 infants, 25 survived (89%). Neurological examination (Amiel-Tison and Grenier) of 15 infants showed transient anomalies at 6 months in 40% of infants, while a normal neurological examination was present in all patients at 1 year. The development quotient (Griffiths scales) was within normal values in ten and mildly abnormal in two infants tested at 1 year.

CONCLUSION

Management based on early HFOV, eventually associated with surfactant, iNO and ECMO to achieve preoperative stabilisation, resulted in a good survival rate (89%) and good neurodevelopmental outcome at 1 year of age in infants with CDH.

Sequential monitoring of urine-soluble interleukin 2 receptor and interleukin 6 predicts acute rejection of human renal allografts before clinical or laboratory signs of renal dysfunction

BACKGROUND

The significance of noninvasive techniques to the early diagnosis of acute rejection in kidney transplants remains elusive. In this study, we examined whether an early posttransplant increase in serum- and urine-soluble interleukin (IL) 2 receptor (sIL-2R) and IL-6 levels predicted acute rejection.

METHODS

Sequential determinations of serum and urine sIL-2R and IL-6 were performed in the first 30 postoperative days in 40 renal transplant patients. Changes during the posttransplant period observed in 26 patients who had one or more episodes of acute rejection (group A) were compared with those recorded in 14 patients who did not experience acute rejection of their graft (group B).

RESULTS

Serum sIL-2R was higher than normal in patients of groups A and B without statistical differences between the two groups. In the first 3 days after transplantation, urinary sIL-2R was higher than normal in group A but not in group B. Urinary sIL-2R at days 2 and 3 was significantly higher (P<0.05) in group A than in group B. In the first 5 days after transplantation, urinary IL-6 was persistently higher than normal in group A, whereas it progressively decreased to normal value on day 4 in group B. Sudden increases (doubling within 24 hr) in urine IL-6 preceded clinical diagnosis of acute rejection by a mean period of 2 days, with an 87% sensitivity and a 64% specificity, and also predicted recurrent rejection episodes.

CONCLUSIONS

Sequential monitoring of urinary sIL-2R and IL-6 levels does allow very early diagnosis of rejection without invasive procedures. Specifically, high urinary sIL-2R in the first 5 posttransplant days identifies the subgroup of patients at risk. In the subsequent days, a sudden increase in urinary IL-6 occurs in those of the above patients who will indeed reject their graft.

Human herpesvirus 6 (HHV-6) causes severe thymocyte depletion in SCID-hu Thy/Liv mice

Human herpesvirus 6 (HHV-6) is a potentially immunosuppressive agent that may act as a cofactor in the progression of AIDS. Here, we describe the first small animal model of HHV-6 infection. HHV-6 subgroup A, strain GS, efficiently infected the human thymic tissue implanted in SCID-hu Thy/Liv mice, leading to the destruction of the graft. Viral DNA was detected in Thy/Liv implants by quantitative polymerase chain reaction (PCR) as early as 4 d after inoculation and peaked at day 14. The productive nature of the infection was confirmed by electron microscopy and immunohistochemical staining. Atypical thymocytes with prominent nuclear inclusions were detected by histopathology. HHV-6 replication was associated with severe, progressive thymocyte depletion involving all major cellular subsets. However, intrathymic T progenitor cells (ITTPs) appeared to be more severely depleted than the other subpopulations, and a preferred tropism of HHV-6 for ITTPs was demonstrated by quantitative PCR on purified thymocyte subsets. These findings suggest that thymocyte depletion by HHV-6 may be due to infection and destruction of these immature T cell precursors. Similar results were obtained with strain PL-1, a primary isolate belonging to subgroup B. The severity of the lesions observed in this animal model underscores the possibility that HHV-6 may indeed be immunosuppressive in humans.

Protein-losing enteropathy after Fontan operation for tricuspid atresia (imperforate tricuspid valve)

Protein-losing enteropathy occurred in a 7-year-old girl with tricuspid atresia, concordant ventriculo-arterial connexions and a relatively large hypoplastic right ventricle, one year after an atrio-ventricular type of Fontan operation by means of a valveless woven Dacron conduit. Severe conduit regurgitation and a marked enlargement of the hypoplastic right ventricle were demonstrated at recatheterization. Insertion of a bioprosthetic valve at the base of the right atrial appendage led to a dramatic clinical recovery of the patient. The use of a valved conduit is recommended when an atrioventricular type of Fontan repair is planned in patients with tricuspid atresia, concordant ventriculo-arterial connexions and relatively large hypoplastic right ventricle.

Basilar Artery Changes in Fabry Disease

BACKGROUND AND PURPOSE

Dolichoectasia of the basilar artery is a characteristic finding of Fabry disease. However, its prevalence, severity, and course have been poorly studied. This study quantitatively evaluated, by MRA, a panel of basilar artery parameters in a large cohort of patients with Fabry disease.

MATERIALS AND METHODS

Basilar artery mean diameter, curved length, "origin-to-end" linear distance (linear length), and tortuosity index ([curved length ÷ linear length] - 1) were retrospectively measured on 1.5T MRA studies of 110 patients with Fabry disease (mean age, 39.4 ± 18.6 years; 40 males) and 108 control patients (mean age, 42.0 ± 18.2 years; 40 males).

RESULTS

Patients with Fabry disease had increased basilar artery mean diameter (P < .001) and basilar artery linear length (P = .02) compared with control patients. Basilar artery curved length and tortuosity index correlated with age in both groups (P < .001), whereas basilar artery linear length correlated with age only in patients with Fabry disease (P = .002). Patients with Fabry disease showed a basilar artery curved length mean increase of 4.2% (9.7% in male patients with Fabry disease versus male control patients), whereas the basilar artery mean diameter had a mean increase of 12.4% (14.3% in male patients with Fabry disease versus male control patients). Male patients with Fabry disease had increased basilar artery mean diameter, curved length, and tortuosity index compared with female patients with Fabry disease (P = .04, P = .02, and P < .001, respectively) and male control patients (P < .001, P = .01, and P = .006, respectively). Female patients with Fabry disease demonstrated an age-dependent increase of basilar artery mean diameter that became significant (P < .001) compared with female control patients above the age of 45 years.

CONCLUSIONS

The basilar artery of patients with FD is subjected to major remodeling that differs according to age and sex, thus providing interesting clues about the pathophysiology of cerebral vessels in Fabry disease.

Endodermal sinus (yolk sac) tumor of the urachus

A rare case of endodermal sinus (yolk sac) tumor of urachal remnants in a two-year-old infant is described. The tumor was located in the upper part of the bladder and appeared to arise from urachal remnants. The tumor could be entirely removed. The patient is free of tumor after three years and eight months follow-up.

Development of reverse transcriptase PCR assays for detection of active human herpesvirus 6 infection

We developed reverse transcriptase (RT) PCR assays for the detection of mRNA from three spliced genes of human herpesvirus 6 (HHV-6), the immediate-early genes U16/U17 and U89/U90 and the late gene U60/U66. Sequence analysis determined the splicing sites of these genes. The new assays may be instrumental in investigating the association between HHV-6 and disease.

Frequency and clinical significance of human beta-herpesviruses in cervical samples from Italian women

Human papillomaviruses (HPVs) are necessary, but not sufficient, for the development of cervical cancer (CC). Human beta-herpesviruses (beta-HHVs) have been suggested as possible cofactors in the oncogenesis of CC. In this cross-sectional study, the prevalence and possible association of cytomegalovirus (CMV), HHV-6 and -7 with HPV presence was investigated by quantitative real-time PCR assays in cervical samples obtained from 208 italian women. The two most common high-risk HPV types found were 31 and 16. Overall, the positive rates for CMV, HHV-6 and HHV-7 were 66%, 25%, and 6%, respectively. In particular, the prevalence of CMV was found to be extremely high irrespective of either the cytological category or HPV positivity. The prevalence of HHV-6 DNA was significantly higher in high-grade squamous intraepithelial lesions (HSIL) respect to normal women (P < 0.017); by contrast, the prevalence HHV-7 DNA was generally low and not associated with SIL. Copresence of CMV and HHV-6 DNA was found to be significantly higher in patients with SIL respect to normal women (P < 0.05). No correlation was demonstrated between the viral load of all three beta-HHVs and the different cytological stages or with the HPV presence. A few patients with severe disease however showed very high viral loads which for HHV-6 may be indicative of viral integration. In conclusion, this study suggests that CMV and HHV-7 alone are probably not implicated in the oncogenesis of CC whilst HHV-6 alone or together with CMV may contribute to the development of CC.

Coinfection of SCID-hu Thy/Liv mice with human herpesvirus 6 and human immunodeficiency virus type 1

Human herpesvirus 6 (HHV-6) has been proposed as a potential cofactor in the progression of human immunodeficiency virus type 1 (HIV-1) disease. We used the SCID-hu Thy/Liv mouse model to evaluate the in vivo interactions between HHV-6 and HIV-1. Our results demonstrate that HHV-6 and HIV-1 can simultaneously replicate in the human thymus in vivo. In this model, however, the presence of one virus appears not to modify the replication or cytopathicity of the other.

A new technical variant for extramucosal pyloromyotomy: the Tan-Bianchi operation moves to the right

BACKGROUND

Since its first publication in 1986, the Tan-Bianchi procedure for treatment of infantile hypertrophic pyloric stenosis has displayed a growing consensus among pediatric surgeons. However, in up to 30% of cases, the supraumbilical skin fold incision does not allow a comfortable access. Delivery through this route, a large pyloric tumor into the wound to perform a pyloromyotomy, can be fairly difficult and time consuming and may damage the gastric or duodenal serosa by tearing. Other technical variants have been proposed to overcome these limitations, but some are more complicated, some are demanding, and some others can worsen the final cosmetic result.

METHODS

The authors present a personal modification to the Tan-Bianchi procedure that they have successfully applied in the last 25 cases of infantile hypertrophic pyloric stenosis. A right semicircular umbilical skin fold incision is performed. The anterior rectus abdominis muscle (RAM) sheath is incised vertically all around the umbilicus, the muscle is laterally displaced, and its posterior sheath and the peritoneal cavity entered in the same line. Because all incisions lay in the same axis, the abdominal cavity is largely opened by 2 retractors without the need for excessive increased traction as it often happens with the supraumbilical approach.

RESULTS

This technical variant was particularly useful to deliver a very large hypertrophic pyloric muscle into the wound. There were no complications and excellent cosmetic results were obtained in all patients.

CONCLUSIONS

These observations suggest that a right semicircular umbilical skin fold incision is an attractive alternative for pyloromyotomy mostly when facing with a large pyloric tumor.

Cervical aortic arch with aortic obstruction: report of two cases

The occurrence of aortic obstruction in patients with cervical arch is very rare. The clinical and angiocardiographic findings of two patients with this combination of defects are presented. One of these patients, in whom tricuspid atresia with reduced pulmonary blood flow was also present, had a successful resection of the obstruction together with construction of a Waterston shunt.

Communicating bronchopulmonary foregut malformation involving a mixed sequestration/cystic adenomatoid malformation: a case report

The authors report the case of a baby girl with an unusual communicating bronchopulmonary foregut malformation consisting of extralobar pulmonary sequestration and cystic adenomatoid malformation. A well-formed bronchus was the communication between the sequestration and lower esophagus.

Qualitative and quantitative polymerase chain reaction detection of the residual myeloma cell contamination after positive selection of CD34+ cells with small- and large-scale Miltenyi cell sorting system

The purging efficacy of the Miltenyi sorting system was evaluated by qualitative and TaqMan quantitative polymerase chain reaction (PCR) in myeloma patients, using immunoglobulin genes. After small-scale selection, qualitative PCR showed that in 6 of 12 leukaphereses myeloma cells were no longer detectable. Envisaging a possible clinical application, the leukaphereses from three patients underwent large-scale selection. Qualitative PCR showed that myeloma cells were still detectable. Quantitative PCR, performed in two patients, showed a tumour depletion of 1 and 2 logs respectively. Although numbers are small, the promising results obtained with small-scale selection were not reproduced in large-scale experiments.

Surgical repair of persistent truncus arteriosus in infancy

Fourteen patients younger than two years of age with persistent truncus arteriosus underwent primary repair. Twelve of them were less than 1 year and 4 less than 3 months of age. Intractable heart failure was the indication for surgery in all patients but one who had increased pulmonary vascular resistance. There were 5 hospital and 2 late deaths. Six out of the 7 survivors (median follow-up: 29 months) were symptom-free. The remaining infant who preoperatively had significant truncal valve regurgitation was doing fairly well 2 1/2 years after repair. Our experience suggests that, although the mortality remains high, primary repair for infants with persistent truncus arteriosus is feasible and offers better overall results than does pulmonary artery banding followed by later intracardiac repair. We advise primary repair for all infants with intractable heart failure or increasing pulmonary vascular resistance with or without truncal valve regurgitation. Elective repair is recommended before the age of 2 years to minimize the risk of pulmonary vascular disease.

Open-heart palliative surgery for pulmonary atresia with ventricular septal defect and hypoplastic pulmonary arteries

The surgical management of pulmonary atresia with ventricular septal defect (VSD) and hypoplastic pulmonary arteries poses difficult problems. Adequate palliation was achieved in two such patients by restoring continuity between the right ventricle and the pulmonary arteries by means of a woven Dacron patch. The VSD was left unrepaired. Angiography performed one month after operation showed the reconstructed pulmonary outflow tract to be widely patent and the pulmonary arteries to be enlarged. This approach may allow subsequent total correction by closure of the VSD in these hopeless patients.

Heterotopic rectal gastric mucosa: a rare cause of lower gastrointestinal bleeding in children. Case report and review of pediatric literature

The authors report a very unusual case of intermittent and painful rectal bleeding occurring in a two-year-old female. At proctosigmoidoscopy, a bluish mucosal fold was found in the rectal ampulla. Histological examination showed the presence of heterotopic gastric mucosa islands intermingled with normal rectal mucosa. Surgical transanal excision of the lesion was undertaken due to the persistence of rectal bleeding with anemia, notwithstanding a three-month course of pharmacological therapy with a proton pump inhibitor. At a one-year follow-up, the child is well and symptom-free. The international pediatric literature was reviewed.

Distal anterior cerebral artery aneurysms: endovascular or surgical treatment? A case report

Cerebral aneurysms are occasionally associated with anomalies of the cerebral arteries. Most reports on anomalies of the anterior cerebral artery have been concerned with hypoplasia, fenestration and the infra-optic course of the A1, variant A1 perforators or Heubner's artery, multi-channeled anterior communicating artery, and azygos anterior cerebral artery. Distal anterior cerebral artery (ACA) aneurysms are known to have a poor clinical course and prognosis compared to other supratentorial aneurysms. The presence of the unpaired, distal, postcommunicating (A2) segment of the ACA is very rare in adults. We describe a patient with a ruptured aneurysm arising from the proximal end of the azygos ACA, first surgically treated with clipping and then with endovascular coiling. A 37-year-old woman at 34 weeks' gestation was transferred to our emergency room with sudden onset of severe headache and vomiting. Computed tomography (CT) revealed subarachnoid hemorrhage in the basal cisterna and the sylvian and interhemispheric fissures. Cerebral angiography showed an azygos ACA, a saccular aneurysm at the junction of the azygos ACA and the right A1 segment. A right fronto-temporal craniotomy was performed in the day of admission, and the neck of the aneurysm was clipped. One year later, an angiographic control examination revealed a regrowth of the aneurysm. The patient underwent endovascular treatment with coiling. Aneurysms of the azygos ACA are rare and their pathogenesis and course are still a matter of discussion. Developmental abnormalities or dynamic vessel wall stresses can explain the high incidence of aneurysms in these cases. The association of a rare anatomical variant with an aneurysm in the same location may suggest an embryogenesis alteration in the Willis circulation.

Results of systemic-to-pulmonary artery anastomosis for tricuspid atresia with reduced pulmonary blood flow

Fifty-six patients with tricuspid atresia and decreased pulmonary blood flow received a systemic-to-pulmonary artery anastomosis as a preliminary operation. Thirty-five had a Waterston shunt, 12 a Blalock-Taussig anastomosis, and nine various other procedures. The age at operation ranged from 2 days to 10 years (median 4.5 months). Pulmonary atresia was present in eight newborn infants. Four patients (7%), all less than 3 months old, died in hospital from persistent servere hypoxia despite the palliative procedure. By actuarial methods, 93% of the survivors were alive at and after one year (longest follow-up:9.8 years), while 83% had not required further palliation at and after four years from the first operation. None of the patients subsequently restudied had raised pulmonary pressure or resistances, and in most of them the pulmonary arterial tree was deemed adequate for the Fontan operation.

Extracorporeal Membrane Oxygenation with Veno-Venous Bypass and Apneic Oxygenation for Treatment of Severe Neonatal Respiratory Failure

Seven newborn infants with life-threatening respiratory failure were treated with veno-venous (V-V) extracorporeal lung support and apneic oxygenation after maximal ventilatory and pharmacological treatment failed. Diagnosis were meconium aspiration syndrome in 3 cases, respiratory distress syndrome in 2, sepsis in 1, congenital diaphragmatic hernia in 1. Before ECMO 6 infants received tolazoline, 4 surfactant, 3 high frequency ventilation, 1 prostaglandin E, 1 epoprostenol, 2 nitric oxide. Newborns were highly hypoxemic at admission and all but one underwent rescue cannulation. V-V bypass was performed with a single lumen single cannula and tidal flow was generated by an alternating clamp using a non-occlusive roller pump. The mean duration of bypass was 162, 4±162.3 hours and infants were extubated 94.5±74.8 hours after decannulation. Five newborns survived and two died. Growth and neurologic development of the older children is normal. The extracorporeal lung support with V-V bypass associated with apneic oxygenation was effective in reversing severe neonatal respiratory failure unresponsive to maximal ventilatory and pharmacological support. An early referral, prior to meeting ECMO criteria, is important in order to avoid hypoxic complications preceding ECMO.

Transposition of the great arteries. Successful Senning's operation in 35 consecutive patients

Mustard's operation for TGA (transposition of the great arteries) has been obstructive complications. In order to try to avoid these complications, we used Senning's operation for TGA. Our experience in 35 consecutive cases is reported. There were no operative or late deaths. Four patients had a PDA; three had a significant VSD with subpulmonary stenosis in two. Previous atrial septectomy and persistent LSVC did not represent contraindications to this procedure. The postoperative course has been smooth and uneventful in all patients. Follow-up periods of one to twenty months demonstrated sinus rhythm in all patients and there were no significant gradients between the venae cavae and the new systemic atrium in 12 reinvestigated patients. On the basis of these results, Senning's operation is recommended as a valid alternative to Mustard's operation.

The epilepsy specialist nurse: A mixed-methods case study on the role and activities

PURPOSE

To describe the role and activities of epilepsy specialist nurses (ESNs) operating as a team in the setting of a hospital specialising in the diagnosis and management of seizure disorders.

METHODS

We conducted a descriptive mixed-methods embedded single case study. We recruited 9 ESNs, 14 of their professional colleagues and 9 'key informants' to analyse their perceptions of the role and activities of ESNs. We collected data through interviews, questionnaires, observations, and documentation. The study was conducted at the Filadelfia Epilepsy Hospital, Denmark.

RESULTS

The team of ESNs offers holistic care to patients and their caregivers regarding the clinical, social, and emotional aspects of epilepsy. The ESNs are integrated in a multidisciplinary team and promote collaboration among the team members. ESNs also contribute to organisational aspects and perform research activities.

CONCLUSION

A structured group of ESNs can operate effectively and extensively in a specialised hospital setting. Our findings contribute to clarifying the description of the ESN's role, and provide an example of how ESNs can be incorporated into a hospital's organisational structure.