Paraoxonase 1 polymorphisms (L55M and Q192R) as a genetic marker of diabetic nephropathy in youth with type 1 diabetes.

INTRODUCTION: Paraoxonase 1 (PON1) polymorphisms have been largely involved in diabetes complications. The aim of the study is to evaluate the effects of PON1 polymorphisms (L55M and Q192R) on diabetic nephropathy (DN). MATERIAL AND METHODS: The study involved 116 children and adolescents with type 1 diabetes (T1D) and 91 healthy subjects. Albumin excretion rate (AER) was determined by immunoturbidimetry. PON1 activity was measured by a spectrophotometric method, and genotyping of PON1 gene was assessed by multiplex PCR followed by RFLP. RESULTS: PON1 activity was inversely correlated to AER (r = -0.245, p = 0.008). A significant decrease (p = 0.037) in PON1 activity was shown between patients with nephropathy and those without (162 [57-618] vs. 316 [37-788] IU/L, respectively). The distribution of AER was, for L55M polymorphism MM > LM > LL (p = 0.002), and for Q192R polymorphism QQ > QR > RR (p < 0.001). The opposite distribution was noted for PON 1 activity (p < 0.001). LMQQ and MMQQ haplotypes seem to increase AER (p = 0.004, p = 0.003, respectively) and to reduce PON1 activity (p = 0.011, p = 0.052, respectively) in youths with T1D. However, LLRR haplotype seems to have the opposite effect. CONCLUSIONS: This study demonstrated that PON1 polymorphisms L55M and Q192R seem to be genetic markers involved in the development of DN in T1D. (Endokrynol Pol 2017; 68 (1): 35-41).

Osteoprotegerin as a marker of cardiovascular risk in children and adolescents with type 1 diabetes.

BACKGROUND: Elevated osteoprotegerin (OPG) levels have been reported in patients with diabetes complications. We investigated whether plasma OPG levels can be used as a marker of cardiovascular risk in children and adolescents with type 1 diabetes (T1D). METHODS: Plasma blood samples were obtained from 243 subjects (143 children and adolescents with T1D and 100 healthy controls). OPG concentrations were measured by enzyme-linked immunosorbent assay (ELISA) method. All data were analyzed by using PASW statistics 18. RESULTS: A significant higher plasma OPG level was found in children with T1D compared to controls (p < 0.001). A significant increase of OPG levels has been related to the glucose level ≥ 7 mmol/L (2.44 [0.01-6.22] vs. 2.16 [0.13-6.22] pmol/L, p = 0.019), microalbuminuria ≥ 30 mg/24 h (3.71 [0.160-6.03] vs. 2.26 [0.01-6.22] pmol/L, p < 0.001), and cystatin-C ≥ 0.789 mg/L (2.64 [0.37-6.22] vs. 2.11 [0.01-5.82] pmol/L, p < 0.001). We noted a significant higher frequency of children with increased cystatin-C levels in the group with elevated plasma level of OPG compared with those with normal levels (49 vs. 18%, respectively) with an odds ratio (OR) = 4.42 [1.41-13.84] (p = 0.006). We showed a significant increase of OPG levels when the number of cardiovascular risk factors exceeds 3 (p = 0.001). CONCLUSION: OPG may be a potential biomarker of cardiovascular risk in T1D. Implementation of OPG determination in the clinical laboratory setting would be useful in order to better stratify patients and to assess the most adequate treatment.

Cosavirus, Salivirus and Bufavirus in Diarrheal Tunisian Infants.

Three newly discovered viruses have been recently described in diarrheal patients: Cosavirus (CosV) and Salivirus (SalV), two picornaviruses, and Bufavirus (BuV), a parvovirus. The detection rate and the role of these viruses remain to be established in acute gastroenteritis (AGE) in diarrheal Tunisian infants. From October 2010 through March 2012, stool samples were collected from 203 children <5 years-old suffering from AGE and attending the Children's Hospital in Monastir, Tunisia. All samples were screened for CosV, SalV and BuV as well as for norovirus (NoV) and group A rotavirus (RVA) by molecular biology. Positive samples for the three screened viruses were also tested for astrovirus, sapovirus, adenovirus, and Aichi virus, then genotyped when technically feasible. During the study period, 11 (5.4%) samples were positive for one of the three investigated viruses: 2 (1.0%) CosV-A10, 7 (3.5%) SalV-A1 and 2 (1.0%) BuV-1, whereas 71 (35.0%) children were infected with NoV and 50 (24.6%) with RVA. No mixed infections involving the three viruses were found, but multiple infections with up to 4 classic enteric viruses were found in all cases. Although these viruses are suspected to be responsible for AGE in children, our data showed that this association was uncertain since all infected children also presented infections with several enteric viruses, suggesting here potential water-borne transmission. Therefore, further studies with large cohorts of healthy and diarrheal children will be needed to evaluate their clinical role in AGE.

A Founder Effect of c.257 + 2T > C Mutation in NCF2 Gene Underlies Severe Chronic Granulomatous Disease in Eleven Patients.

Chronic granulomatous disease (CGD) is the prototypic functional neutrophil disorder caused by genetic defects in one of the five genes encoding the superoxide-generating nicotinamide adenine dinucleotide phosphate (NADPH)-oxidase subunits of phagocytes. Mutations causing the most prevalent form of CGD in western populations are located in the X-linked-CYBB gene. The four remaining autosomal recessive (AR) forms collectively account for one-third of CGD cases. We investigated the clinical and molecular features of eleven patients with CGD from 6 consanguineous families, originating from contiguous regions in the west of Tunisia. The patients' clinical phenotype is characterized by a high incidence of mycobacterial infections. Five out of the eleven patients died despite treatment arguing in favor of a severe clinical form of CGD. These findings correlated with the absence of functional p67phox protein as well as the absence of residual reactive oxygen intermediates (ROI) production. Genetic analysis showed the presence, in all patients, of a unique mutation (c.257 + 2T > C) in NCF2 gene predicted to affect RNA splicing. Segregating analysis using nine polymorphic markers overlapping the NCF2 gene revealed a common haplotype spanning 4.1 Mb. The founder event responsible for this mutation was estimated to have arisen approximately 175 years ago. These findings will facilitate the implementation of preventive approaches through genetic counseling in affected consanguineous families.

Enterovirus meningitis in Tunisia (Monastir, Mahdia, 2011-2013): identification of virus variants cocirculating in France.

Acute enterovirus (EV) meningitis is a frequent cause of hospitalisation, and over 100 EV serotypes may be involved. A total of 215 patients of all ages with meningitis signs were investigated in 2 Tunisian hospitals. Their cerebrospinal fluid (CSF) was analysed retrospectively for EVs with a TaqMan real-time RT-qPCR. The virus strains were typed, and their evolutionary relationships were determined by Bayesian phylogenetic methods. An EV genome was detected in 21/215 patients (9.8%). The CSF viral loads ranged from 3.27 to 5.63 log10 genome copies/mL. The strains were identified in 13/21 patients and assigned to EV-B types. Viruses identified in Tunisian patients were genetically related to variants detected in France. The viral loads were similar in Tunisian and French patients for most EV types. The phylogenetic data and viral loads determined in Tunisian and French patients suggest that close EV variants were involved in aseptic meningitis in the 2 countries over a same period.

Rotavirus P[8] Infections in Persons with Secretor and Nonsecretor Phenotypes, Tunisia.

To determine whether rotavirus infections are linked to secretor status, we studied samples from children in Tunisia with gastroenteritis. We phenotyped saliva for human blood group antigens and tested feces for rotavirus. Rotavirus was detected in 32/114 patients. Secretor genotyping showed that P[8] rotavirus infected secretors and nonsecretors, and infection correlated with presence of Lewis antigen.

Partial KCNQ1OT1 hypomethylation: A disguised familial Beckwith-Wiedemann syndrome as a sporadic adrenocortical tumor.

Beckwith-Wiedemann syndrome has a wide spectrum of complications such as embryonal tumors, namely adrenocortical tumor. Tumor predisposition is one of the most challenging manifestations of this syndrome. A 45-day old female with a family history of adrenocortical tumor presented with adrenocortical tumor. The case raised suspicion of a hereditary Beckwith-Wiedemann syndrome, therefore molecular analysis was undertaken. The results revealed partial KCNQ1OT1 hypomethylation in the infant's blood DNA which was associated with a complete loss of methylation in the infant's adrenocortical tumor tissue. It is unique for familial Beckwith-Wiedemann syndrome caused by KCNQ1OT1 partial hypomethylation to manifest solely through adrenocortical tumor. Incomplete penetrance and specific tissue mosaicism could provide explanations to this novel hereditary Beckwith-Wiedemann syndrome presentation.

Can paraoxonase 1 polymorphisms (L55 M and Q192 R) protect children with type 1 diabetes against lipid abnormalities?

BACKGROUND: Only a few studies have focused on the possible modulatory role of paraoxonase 1 (PON1) polymorphisms in lipid profiles, especially in children and in adolescents with type 1 diabetes (T1D). OBJECTIVE: We propose to study the association between PON1 polymorphisms (PON1-55 and PON1-192) and a lipid profile in a young Tunisian population with T1D. METHODS: The study compared 122 children and adolescents with T1D with 97 controls. Genomic DNA was collected from 116 patients and 91 controls. Lipid parameters were determined by automated methods. PON1 activity was measured by a spectrophotometric method and genotyping of the PON1 gene was assessed by multiplex polymerase chain reaction followed by restriction fragment-length polymorphism. RESULTS: A significant increase in total cholesterol, high-density lipoprotein-cholesterol, low-density lipoprotein-cholesterol (LDL-C), apolipoprotein B (ApoB), and lipoprotein (a) (Lp(a)) and a significant decrease in apolipoprotein A1 (ApoA1), ApoA1/ApoB ratio, and PON1 activity/HDL-C ratio were observed in children with T1D compared with controls. In the LLQR haplotype, the group with diabetes showed significantly higher values of total cholesterol, LDL-C, apoB, Lp(a), and apoA1/apoB ratio compared with the control group. Those with diabetes with the LLQQ haplotype showed a significant decrease in LDL-C and Lp(a) compared with controls (P < .0001). CONCLUSION: PON1 polymorphisms (PON1-55 and PON1-192) seem to be involved in the altering the lipid profile in T1D. The LLQR haplotype provided an atherogenic lipid profile in children with T1D compared with controls. LLQQ haplotype seemed to have a protective effect against the increase in LDL-C and Lp(a) that are heavily involved in the development of cardiovascular diseases.

Congenital pulmonary alveolar proteinosis.

Pulmonary alveolar proteinosis (PAP) is a rare syndrome characterized by pulmonary surfactant accumulation within the alveolar spaces. It occurs with a reported prevalence of 0.1 per 100,000 individuals. Two clinically different pediatric types have been defined as congenital PAP which is fatal and a late-onset PAP which is similar to the adult form and less severe. The clinical course of PAP is variable, ranging from spontaneous remission to respiratory failure. Whole-lung lavage is the current standard treatment for PAP patients. We report a new congenital case of PAP.

Detection of herpes simplex virus (1 and 2), varicella-zoster virus, cytomegalovirus, human herpesvirus 6 and enterovirus in immunocompetent Tunisian patients with acute neuromeningeal disorder.

Enteroviruses (EVs) and human herpesviruses (HHVs) are involved frequently in acute neurological disorders of viral etiology. This study aimed to investigate the incidence of herpes simplex virus types-1 (HSV-1) and 2 (HSV-2), varicella-zoster virus (VZV), cytomegalovirus (CMV), human herpesvirus 6 (HHV-6) and human enteroviruses (EVs) in cerebrospinal fluid (CSF) samples of Tunisian immunocompetent patients with neuromeningeal disorders. The patients had been hospitalized at the Fattouma Bourguiba University Hospital (Monastir, Tunisia) between September 2007 and June 2009. At least one viral genome was detected in 58 (46%) out of 126 CSF samples collected. Enterovirus was detected in 31 of the positive samples (53.4%), CMV in 20 (34.5%), HSV-1 in 3 (5.2%), HSV-2 in 6 (10.3%), VZV in 4 (6.9%), HHV-6 in 2 (3.4%). More than one viral genome was detected in seven CSF samples, including CMV DNA in six of the samples. The high frequency of enteroviral infections in aseptic meningitis was confirmed. The detection of CMV DNA only suggests a direct role of this virus in the etiology of acute neuromeningeal disorder.

Enteroviral central nervous system infections in children of the region of monastir, Tunisia: diagnosis, laboratory findings of cerebrospinal fluid and clinical manifestations.

Human enteroviruses (HEV) are one of the major causes of central nervous system (CNS) infections in pediatrics. A prospective study was conducted to assess the epidemiological, clinical, and laboratory characteristics of enterovirus (EV) infections of the CNS in children under 15-years-old, suspected of having viral CNS infections and admitted to the Pediatric Department of Monastir University Hospital, Tunisia. Enteroviral RNA was detected by 5' NCR nested RT-PCR assay in 33 % (20 out of 60) of cerebrospinal fluid specimens, whereas only six samples (10 %) were EV positive in cell culture. EV-positive patients were clustered according to their clinical manifestations, predominantly diagnosed as aseptic meningitis (65 %) and meningoencephalitis (20 %). Fever, headache, vomiting, and neck stiffness were the most pronounced symptoms. Pleocytosis with the predominance of lymphocytes was observed in 60 % of EV positive specimens. Although patients suffering from EV infections were encountered throughout the year, most occurred during spring and summer months. Using VP1-2A nested RT-PCR and sequence analysis, three of the 20 positive HEV were identified as Echovirus (E)-9. This is the first report of a cluster of aseptic meningitis cases caused by E-9 in Monastir.

Molecular epidemiology and clinical characterization of group A rotavirus infections in Tunisian children with acute gastroenteritis.

Rotaviruses are the most common cause of severe viral gastroenteritis in early childhood worldwide. Thus, the objectives of our study were to determine the molecular epidemiology and the clinical features of rotavirus gastroenteritis in Tunisia. Between January 2003 and April 2007, a prospective study was conducted on 788 stool samples collected from children under 12 years of age who were suffering from acute gastroenteritis. Rotavirus was detected by multiplex RT-PCR in 27% (n = 213) of samples, among them 79.3% (n = 169) cases were monoinfections. The frequency of rotavirus infections was significantly higher among inpatients (29%) than among outpatients (13%) (P < 0.001). The seasonal distribution of rotavirus diarrhea showed a winter peak, with an unusual peak from June to September. The mean duration of hospitalization was 6.5 ± 8.1 days and the mean age was 15.8 ± 22.8 months for rotavirus monoinfections. Fever, vomiting, abdominal pain, and dehydration were observed in 88, 98, 13, and 80 cases, respectively, in children with rotavirus monoinfections. G3P[8] (45.6%) and G1P[8] (23.9%) were the most common genotypes found in our study. The determination of rotavirus infection prevalence and the characterization of the rotavirus strains circulating will help us to better understand the molecular biology and epidemiology of the disease in our country.

[Idiopathic steroid-resistant nephrotic syndrome in child : study of 20 cases]. / Syndrome néphrotique idiopathique corticorésistant de l'enfant : Etude de 20 cas.

BACKGROUND: Idiopathic steroid-resistant nephrotic syndrome (ISRNS) is rare and represents a significant therapeutic dilemma for paediatricians and paediatric nephrologists. AIM: To analyze characteristics of the ISRNS in the child. METHODS: Retrospective study of 20 cases of ISRNS enrolled in paediatric department of nephrology in Sahloul hospital (Tunisia) between June 1993 and December 2007 (14 years period). RESULTS: There were eight girls and 12 boys (mean age: 5.8± 3.7 years) originating from the center or the south of Tunisia. Eight of them had a minimal-change disease (MCD), 11 a focal and segmental glomerulosclerosis (FSGS) and one a mesangioproliferative glomerulonephritis (MePGN). In this group, no family form could be identified. All patients were treated by cyclosporine associated with low dose of steroid. We noted a complete remission (CR) in nine cases, partial remission (PR) in three cases and no response to cyclosporine in eight cases. Among patients with CR, six presented MCD and three a FSGS. In this group, we observed relapse of nephrotic syndrome in six cases. End stage renal disease (ESRD) was noted in 10 patients of which five not responded to cyclosporine, two initially having presented a RC and three having since the beginning a PR. Among them, two only could be grafted; one relapses on transplant was observed with a single patient initially presenting a secondarily transformed MePGN in FSGS. CONCLUSION: Our study confirms the clinical, histological and evolutive heterogeneity of idiopathic steroid-resistant nephrotic syndrome. Although there is any therapeutic consensus in this domain, cyclosporine remains indicated in first intention in sporadic forms of ISRNS. On the other hand, renal transplantation constitutes the only therapeutic alternate in genetic forms that constantly evolve at ESRD.

Molecular detection of genogroup I sapovirus in Tunisian children suffering from acute gastroenteritis.

This study investigated the prevalence of sapovirus infections in children with acute gastroenteritis in Monastir region, Tunisia, from January 2003 to April 2007. Sapovirus was characterized by sequence and phylogenetic analyses of the partial polymerase gene. From 788 fecal specimens tested, 6 (0.8%) were positive for sapovirus, of these, 4 (66.7%) were monoinfections. All sapovirus positive samples were detected in outpatient, contrary to norovirus which was significantly more frequent in hospitalized children than in outpatients (14.5 vs. 9.5%, P = 0.03). The mean age of children with sapovirus infections was 11 ± 5.56 months (range 6-19 months). Sapovirus isolates were detected in March and between September and December 2003. Fever, vomiting, abdominal pain, and dehydration were not observed in patients with sapovirus infections. Analysis of nucleotide and amino acid sequences revealed that all 6 Tunisian sapovirus strains clustered in the GGI/1 genotype and strains were identical in the region sequenced, sharing 90.2% nucleotide identity with the reference strain Sapporo/82/JP (U65427). This represents the first finding of sapovirus infections in North Africa and especially in Tunisia. The data indicate that, contrary to norovirus which can cause severe diarrhea and is an important etiologic agent in hospitalized cases, sapovirus causes mild gastroenteritis in Tunisian children.

Infantile scurvy: two case reports.

Background. Ascorbic acid (vitamin C) is necessary for the formation of collagen, reducing free radicals, and aiding in iron absorption. SCURVY, a disease of dietary ascorbic acid deficiency, is uncommon today. It still exists in high risk groups including economically disadvantaged populations with poor nutrition. The incidence of SCURVY in the pediatric population is very low. Cases Report. Here we report two cases of SCURVY revealed by subperiosteal hematoma in children with cerebral palsy and developmental delay. Conclusion. SCURVY is extremely rare in children. Musculoskeletal manifestations are prominent in pediatric SCURVY. Multiple subperiosteal hematomas are an important indicator for diagnosis.

Nail-patella syndrome associated with short stature: a case series.

Introduction. Nail-patella syndrome (NPS) is a rare genetic disorder that is characterized by a pleiotropic malformation affecting the nail, the skeleton, and occasionally the central nervous system and the kidneys. Case Presentation. We report two paediatric cases, which are of two sisters, who aged, respectively, two and five years. They are admitted to explore short stature. The initial clinical examination and radiologic findings confirmed the diagnosis of Nail-patella syndrome. Conclusion. Skeletal, ophthalmologic, and renal involvements were mostly associated with NPS. The association with short stature was exceptional.

Aichi virus IgG seroprevalence in Tunisia parallels genomic detection and clinical presentation in children with gastroenteritis.

Aichi virus has been described as a novel causative agent of gastroenteritis in humans. In this study, we report the seroprevalence distribution of Aichi virus in Tunisia. A panel of 1,000 sera was screened by applying an enzyme-linked immunosorbent assay for immunoglobulin G specific for Aichi virus. A considerable prevalence (92%) of antibody to Aichi virus was found across all age groups. The specific anti-Aichi virus antibodies increased with age, from a high rate (68.8%) in children under 10 years old to about 100% in persons more than 60 years old. We found a statistically significant increase in levels of antibody to Aichi virus according to the age of patients. Immunoglobulin M antibodies were detected among five children. A high frequency of Aichi virus monoinfections in hospitalized children with severe gastroenteritis was previously observed in Tunisia. Aichi virus causes diarrhea with dehydration, fever, and vomiting. This work is the first to establish a correlation between the high seroprevalence of specific Aichi virus antibodies, clinical presentation, and a high frequency of isolation of Aichi virus by genomic characterization in stools of children suffering from gastroenteritis. Our data show the importance and emerging character of Aichi virus in the viral etiology of pediatric gastroenteritis.