Erythropoietic protoporphyria a clinical and molecular study from Lebanon: Ferrochelatase a potential tumor suppressor gene in colon cancer.

Erythropoietic protoporphyria (EPP) is a rare cutaneous and systemic disease caused by mutations in the ferrochelatase gene (FECH). The molecular underpinnings of EPP in Middle Eastern populations and relative to other ethnic groups secondary to increased consanguinity are unknown. To understand the molecular pathogenesis of Middle Eastern EPP, we surveyed clinicopathological and molecular features in 6 large consanguineous families from Lebanon and Syria presenting with cutaneous and systemic features consistent with EPP. We observed 30% increased liver disease and 20% elevated end-stage liver complications in our EPP cohort compared to EPP patients previously reported elsewhere. In addition, Middle Eastern EPP patients in our cohort exhibited uniquely an increased incidence of colon cancer. Sequence analysis revealed 2 novel non-synonymous FECH mutations in the studied families designated p.M294T and p.I230M. In addition, FECH activity was significantly decreased (6%) in fibroblasts obtained from sun-exposed sites in a patient with p.M294T mutation, whereas in sharp contrast, protected sites from the same patient exhibited 54% activity for the gene. We also found that sun-exposed fibroblasts, relative to sun-protected and control fibroblasts, exhibited suppressed growth and atypical morphology in vitro, and that these effects were alleviated when the cells were co-cultured with sun-protected fibroblasts. Our findings on the increased incidence of colon cancer in EPP patients prompted us to survey FECH expression patterns in cancer. Using publicly available microarray datasets we found that FECH mRNA was largely significantly decreased in colon adenocarcinomas relative to normal colon tissues. Our findings suggest that families with autosomal recessive EPP should be screened more extensively for systemic involvement including liver diseases and colon cancer, and point to a previously unknown yet plausible tumor suppressor role for FECH in colon malignancy.

Primary carnitine deficiency: novel mutations and insights into the cardiac phenotype.

Solute carrier family 22 member 5 (SLC22A5) encodes a sodium-dependent ion transporter responsible for shuffling carnitine across the plasma membrane. This process provides energy for the heart, among other organs allowing beta-oxidation of fatty acids. Mutations in SLC22A5 result in primary carnitine deficiency (PCD), a disorder that manifests with cardiac, skeletal, or metabolic symptoms. We hereby describe two novel mutations in SLC22A5 in two Lebanese families associated exclusively with a cardiac phenotype. The frequency of the cardiac, metabolic and skeletal symptoms in PCD patients remains undefined. All the reported eight PCD patients belonging to five different Lebanese families have an exclusive cardiac phenotype. Carnitine levels appear to be directly linked to the type and position of the mutation and the severity of the phenotypic presentation does not seem to be associated with serum carnitine levels. A comprehensive review of 61 literature-reported PCD cases revealed an exclusive cardiac manifestation frequency at 62.3% with a very low likelihood of simultaneous occurrence of cardiac and metabolic manifestation.

Complete heart block in a patient with acute lymphoblastic leukaemia: teicoplanin as a possible cause and review of literature.

WHAT IS KNOWN AND OBJECTIVE: Teicoplanin is a glycopeptide antibiotic used against documented or presumed methicillin-resistant infections. We report a 31-month-old boy with acute lymphocytic leukaemia who developed permanent complete atrioventricular block (CAVB) necessitating pacemaker insertion after receiving teicoplanin for Staphylococcus epidermidis bacteremia. CASE SUMMARY: Clinical assessment of the child revealed febrile neutropenia. After thorough assessment and work-up, the patient was started on teicoplanin intravenously after which he had sudden onset of bradycardia. Electrocardiography showed CAVB that eventually required permanent pacemaker insertion. Twenty-nine months from the incident, the patient is doing well. WHAT IS NEW AND CONCLUSION: We report on a case of teicoplanin-associated CAVB in a child with acute lymphoblastic leukaemia (ALL). This is one of only two similar cases reported in the literature. Teicoplanin remains the most probable cause. The use of teicoplanin should be approached cautiously in the setting of immunosuppression. Whether VZV contributed and teicoplanin triggered remains speculative. Physicians should be aware of this possible complication.

Ocular pathology in congenital heart disease.

PURPOSE: To describe the ocular findings in subjects with congenital heart disease (CHD). METHODS: In a prospective study, the same observer examined 240 consecutive patients with CHD admitted to the medical centre. Two independent geneticists performed identification of syndromes. RESULTS: The commonest anatomic cardiac anomalies were ventricular or atrial septal defects (62), tetralogy of Fallot (39), pulmonary stenosis (25), and transposition of the great arteries (24). The heart lesions were divided physiologically into volume overload (90), cyanotic (87), and obstructive (63). In all, 105 syndromic subjects included the velocardiofacial syndrome (18), Down's syndrome (17), CHARGE association (6), DiGeorge syndrome (5), Williams syndrome (3), Edwards syndrome (3), Noonan syndrome (3), VACTERL association (2), and Patau syndrome (trisomy 13) (2). The paediatric team recognized 51 patients as syndromic. Two independent geneticists recognized additional 54 patients as syndromic. Positive eye findings were present in 55% (132) and included retinal vascular tortuosity (46), optic disc hypoplasia (30), trichomegaly (15), congenital ptosis (12), strabismus (11), retinal haemorrhages (8), prominent eyes (7), and congenital cataract (6). There was a strong correlation between the retinal vascular tortuosity and both a low haematocrit (P=0.000) and a low arterial oxygen saturation (P=0.002). CONCLUSIONS: Patients with CHD are at a high risk for ocular pathology and need screening for various ocular abnormalities.

A new patient with pure trisomy 4p resulting from isochromosome formation and whole arm translocation.

Short arm isochromosome formation with translocation of the entire long arm of the same chromosome is an unusual constitutional abnormality that has been observed, to our knowledge, in 18 cases. Only one of these previously reported cases involved chromosome 4, resulting in pure trisomy 4p. Pure trisomy 4p has been reported in a number of cases, the majority of them due to familial chromosome rearrangements, and is associated with a distinct pattern of abnormal findings. We report here a second case of a de novo chromosome 4 whole arm translocation with short-arm isochromosome formation, which we have delineated further by FISH studies.

Doppler characterization of left ventricular diastolic function in beta-thalassaemia major. Evidence for an early stage of impaired relaxation.

AIMS: Doppler echocardiographic studies of left ventricular diastolic function in patients with thalassaemia major have shown conflicting findings. This study was undertaken to compare Doppler echocardiographic parameters of diastolic function among a group of patients with thalassaemia major, a group with thalassaemia intermedia and a group of normal individuals. METHODS AND RESULTS: 50 patients with thalassaemia major, 38 patients with thalassaemia intermedia and 29 normal subjects were studied. All had normal systolic function. The thalassaemia intermedia patients had larger body surface area and left ventricular mass index than the thalassaemia major patients but less than the controls. The ratios between peak early and late mitral diastolic flow (E/A ratio) were comparable between the three groups. The haematocrit levels were comparable in the two study groups, but the ferritin levels were significantly higher in the thalassaemia major group (P<0.001). Using multiple regression analysis to correct for the influence of heart rate, age and body surface area, we found a prolonged isovolumic relaxation time (P<0.03) and a lower E wave (P<0.001) in the thalassaemia major group as compared to the thalassaemia intermedia group. The isovolumic relaxation time also differed significantly between the thalassaemia groups and the control (P<0.001), suggesting a state of impaired relaxation most notable in thalassaemia major that is probably due to iron overload. CONCLUSION: In patients with thalassaemia major and normal systolic function who have iron overload, the earliest sign of diastolic dysfunction is an impairment in left ventricular relaxation manifested as a prolonged isovolumic relaxation time.

Pseudomonas pericarditis in an immunocompetent newborn: unusual presentation with review of the literature.

Acute purulent pericarditis is a rare entity in the neonatal age group. The most common isolated organisms are Staphylococcus aureus, Haemophilus influenzae, and Streptococcus pneumoniae. Other organisms, like Pseudomonas aeruginosa, have been seldom implicated with only one case of Pseudomonas pericarditis reported in the neonatal period. The prognosis is often considered very poor in this age group. This article describes Pseudomonas pericarditis in a 1-week-old immunocompetent female newborn who was successfully managed with combined medical and surgical therapy.

Treatment of rheumatic carditis with intravenous gammaglobulin: is there a beneficial effect?

Rheumatic carditis is a major manifestation of acute rheumatic fever. Conventional therapy includes the use of salicylates and steroids. To date, however, such therapy has not been proven to have a clear benefit in reducing valvar heart disease. We report the use of high-dose intravenous immunoglobulin in two chidlren with acute rheumatic carditis in whom we have been able to document the beneficial effect.

Cerebral mycotic aneurysm in a child with Down's syndrome: a unique association.

Mycotic aneurysms are rare complications in patients with infective endocarditis, particularly in the pediatric population. We report a case of mycotic aneurysm of the middle cerebral artery complicating bacterial endocarditis in a child with Down's syndrome. The patient was successfully treated medically without the need for surgical intervention.

Effects of SCO-spondin thrombospondin type 1 repeats (TSR) in comparison to Reissner's fiber material on the differentiation of the B104 neuroblastoma cell line.

SCO-spondin is a newly identified protein that is strongly expressed in the subcommissural organ (SCO), an ependymal differentiation of the brain. When released into the cerebrospinal fluid at the entrance to the Sylvian aqueduct, the glycoproteins condense and form a thread-like structure, Reissner's fiber (RF). To analyze the role of SCO-spondin on neuronal development, we studied the effects induced by an oligopeptide derived from a thrombospondin type 1 repeat (TSR) of SCO-spondin on neuroblastoma B104 cells and compared them with the effects of soluble RF material containing complete SCO-spondin proteins. In low density cell culture, the TSR peptide first induced a notable flattening of cells accompanied by increased neurite outgrowth. Grouping of these differentiated B104 cells, which later formed dense aggregates, was then observed with increasing time in culture. Soluble RF material induced similar morphological changes and neurite-promoting effects on B104 cells, although the cells remained evenly distributed throughout the culture time and no aggregates were visible. In high-density cell culture, both TSR peptide and RF material induced prominent neurite outgrowth and subsequent rapid cell aggregation. Whereas soluble RF material inhibited cell proliferation, no respective effect was observed in the presence of the TSR peptide. A direct interaction of TSR peptide and soluble RF material with a B104 cell binding site was revealed by increased B104 cell metabolic activity by flow cytometry.

Cardiac disease in children in Lebanon: the AUB-MC Children's Cardiac Registry experience.

OBJECTIVE: To study the epidemiology of cardiac disease in children and their outcome in Lebanon, we established a Children's Cardiac Registry Center (CCRC) at the American University of Beirut-Medical Center. DESIGN/METHODS: The CCRC included prospectively all pediatric patients with congenital heart disease (CHD) and/or acquired heart disease (AHD) who were evaluated at our center, between March 1, 1997 and July 31, 2000. RESULTS: Out of the 1000 patients with cardiac anomalies enrolled in the CCRC, 917 (91.7%) had CHD and the rest had AHD. Ventricular septal defect was the most common cardiac malformation with a relative frequency of 25.3%, followed by pulmonary stenosis (14.6%), aortic anomalies (8%), ASD (8%) and tetralogy of Fallot (7.8%). Complex cardiac lesions like HLHS, TGA and AVC had lower frequencies at 0.4%, 3.7% and 3.5% respectively. The most common AHD was rheumatic heart disease (42.2%). 34.9% of the registry patients with CHD and 10.8% with AHD underwent surgical intervention. There were 4.8% and 2.4% mortality rates in the CHD and AHD groups, respectively during the 40-month study period. CONCLUSION: The prevalence of many of the cardiac malformations in the CCRC was similar to that reported in the literature. However, some of the complex cardiac lesions were less common. The outcome of the two groups of patients is comparable to the outcome of children with cardiac malformation from developed countries. The establishment of a registry at the national level is important. Appropriate identification of the cardiac disease, its epidemiology, and outcome is of utmost importance in guiding adequate care.

Aspergillus vertebral osteomyelitis in a child with a primary monocyte killing defect: response to GM-CSF therapy.

We report the first case of vertebral aspergillosis in a child with a primary defect in monocyte killing, an extremely rare immunodeficiency The diagnosis of defective monocyte killing was made by an in vitro assay that showed normal killing of Staphylococcus aureus by the patient's neutrophils but impaired killing by his monocytes. Importantly, the extensive granulomatous infection that involved the vertebral column, posterior mediastinum, pleura, and lung was not responsive to aggressive treatment with a combination of liposomal amphotericin B. intralesional amphotericin B. itraconazole, and granulocyte transfusions. Dramatic clinical and radiological improvement was only seen after the addition of granulocyte macrophage-colony stimulating factor (GM-CSF) to his treatment regimen. The use of GM-CSF in the treatment of invasive aspergillosis in immunocompromised patients requires further evaluation.

Subcommissural organ/Reissner's fiber complex: characterization of SCO-spondin, a glycoprotein with potent activity on neurite outgrowth.

In the developing vertebrate nervous system, several proteins of the thrombospondin superfamily act on axonal pathfinding. By successive screening of a SCO-cDNA library, we have characterized a new member of this superfamily, which we call SCO-spondin. This extracellular matrix glycoprotein of 4,560 amino acids is expressed and secreted early in development by the subcommissural organ (SCO), an ependymal differentiation located in the roof of the Sylvian aqueduct. Furthermore, SCO-spondin makes part of Reissner's fiber (RF), a thread-like structure present in the central canal of the spinal cord. This novel protein shows a unique arrangement of several conserved domains, including 26 thrombospondin type 1 repeats (TSR), nine low-density lipoprotein receptor (LDLr) type A domains, two epidermal growth factor (EGF)-like domains, and N- and C-terminal von Willebrand factor (vWF) cysteine-rich domains, all of which are potent sites of protein-protein interaction. Regarding the huge number of TSR, the putative function of SCO-spondin on axonal guidance is discussed in comparison with other developmental molecules of the CNS exhibiting TSR. To correlate SCO-spondin molecular feature and function, we tested the effect of oligopeptides, whose sequences include highly conserved amino acids of the consensus domains on a neuroblastoma cell line B 104. One of these peptides (WSGWSSCSRSCG) markedly increased neurite outgrowth of B 104 cells and this effect was dose dependent. Thus, SCO-spondin is a favorable substrate for neurite outgrowth and may participate in the posterior commissure formation and spinal cord differentiation during ontogenesis of the central nervous system.

Paediatric infective endocarditis: 19-year experience at a tertiary care hospital in a developing country.

A retrospective study was undertaken to study children who presented with infective endocarditis (IE) to a university teaching hospital in Beirut, Lebanon, between January 1977 and May 1995. Of 41 patients with IE (24F, 17M), 28 (68%) were diagnosed between 1977 and 1985. Patients' ages ranged from 3 to 18 y (mean age 11.3+/-2.8 y), and 13 patients were <10 y of age. Clinical presentations included: fever (in 88%), heart failure (in 39%), neurologic findings (in 20%) and embolic phenomena (in 22%). Nineteen patients (46%) had underlying congenital heart disease (CHD) with tetralogy of Fallot and pulmonary stenosis being the most common. Sixteen patients (39%) had underlying rheumatic heart disease (RHD). A total of 5 children (12%) with normal cardiac anatomy had IE. One had underlying acquired viral myocarditis with mitral insufficiency. Echocardiography showed vegetations in 60%. Blood cultures were positive in 31 patients (76%). IE occurred in three patients following cardiac surgery. In one patient it occurred within 2 mo of surgery and in the other two it occurred within 6 mo. Streptococcus viridans and Staphylococcus aureus were the two most commonly isolated bacteria. Overall mortality rate was 29% (not statistically significant between patients presenting between 1977-1985 and 1986-1995; p = 0.17). There was no statistically significant difference in mortality among the groups (five in the group with CHD, six with RHD and one with structurally normal heart). This study demonstrates that RHD is an important underlying cause of IE in children in our community. This finding is similar to those in other developing countries and different from those in developed countries. Distribution of pathogens and CHD in our study is comparable to some reports in the literature, except for the higher proportion of patients with underlying pulmonary stenosis. Bacterial endocarditis prophylaxis should be emphasized in patients with RHD or pulmonary stenosis.

Rheumatic fever in children: a 15-year experience in a developing country.

Clinical data from 91 patients with rheumatic fever (RF), who were hospitalized at a tertiary hospital in Lebanon between 1980 and 1995, were reviewed retrospectively. Age on hospitalization was 11.1+/-2.9 years (mean +/- SD, range 3-17 years). Nineteen patients were <6 years of age. Manifestations included carditis (93%), arthritis (39%), Sydenham's chorea (2%), erythema marginatum (4%), subcutaneous nodules (1%), fever (62%), arthralgia (55%), and acute congestive heart failure (CHF) on initial presentation (44%). Pericardial effusion occurred in 11%. There was positive family history of RF in 14%. Mitral insufficiency and aortic insufficiency occurred in 67 and 35%, respectively. Both mitral and aortic valves were involved in 30% of cases. Tricuspid insufficiency developed in 3% and pulmonary insufficiency in 1%. Mitral stenosis developed in 19%. Twenty-eight patients underwent surgical intervention: mitral valve repair and commissurotomy in 9/91 (10%), mitral valve replacement in 18/91 (20%), and aortic valve replacement in 9/91 (10%). Overall mortality was 12%: 5 following surgical intervention (3 after mitral valve surgery and 2 after mitral and aortic valve surgery). All patients that died had CHF on initial presentation (p = 0.006). This study includes hospitalized patients with predominant rheumatic heart disease. Initial presentation with CHF is a risk factor for surgical intervention and mortality. A significant high surgical intervention rate is noted that is probably related to the nature of the selected group studied. This study emphasizes the significant morbidity and death in patients with RF and carditis.

Characterization of a cDNA encoding a rice mitochondrial voltage-dependent anion channel and its gene expression studied upon plant development and osmotic stress.

The voltage-dependent anion channel (VDAC) of mitochondria forms a large pore in the outer envelope membrane. Here, the full Oryza sativa OSVDAC1 cDNA was sequenced and is shown to belong to a small multigene family in the rice genome. This cDNA is 1093 bp long and codes for a protein of 274 amino acids. Expression studies of the osvdac1 gene show a regulation of its level in function of the plantlets maturation and organs. In contrast with several bacterial porins, osmotic stress does not have any effect on the plant osvdac1 gene expression.