A gain-of-function mutation in zinc cluster transcription factor Rob1 drives Candida albicans adaptive growth in the cystic fibrosis lung environment.

Candida albicans chronically colonizes the respiratory tract of patients with Cystic Fibrosis (CF). It competes with CF-associated pathogens (e.g. Pseudomonas aeruginosa) and contributes to disease severity. We hypothesize that C. albicans undergoes specific adaptation mechanisms that explain its persistence in the CF lung environment. To identify the underlying genetic and phenotypic determinants, we serially recovered 146 C. albicans clinical isolates over a period of 30 months from the sputum of 25 antifungal-naive CF patients. Multilocus sequence typing analyses revealed that most patients were individually colonized with genetically close strains, facilitating comparative analyses between serial isolates. We strikingly observed differential ability to filament and form monospecies and dual-species biofilms with P. aeruginosa among 18 serial isolates sharing the same diploid sequence type, recovered within one year from a pediatric patient. Whole genome sequencing revealed that their genomes were highly heterozygous and similar to each other, displaying a highly clonal subpopulation structure. Data mining identified 34 non-synonymous heterozygous SNPs in 19 open reading frames differentiating the hyperfilamentous and strong biofilm-former strains from the remaining isolates. Among these, we detected a glycine-to-glutamate substitution at position 299 (G299E) in the deduced amino acid sequence of the zinc cluster transcription factor ROB1 (ROB1G299E), encoding a major regulator of filamentous growth and biofilm formation. Introduction of the G299E heterozygous mutation in a co-isolated weak biofilm-former CF strain was sufficient to confer hyperfilamentous growth, increased expression of hyphal-specific genes, increased monospecies biofilm formation and increased survival in dual-species biofilms formed with P. aeruginosa, indicating that ROB1G299E is a gain-of-function mutation. Disruption of ROB1 in a hyperfilamentous isolate carrying the ROB1G299E allele abolished hyperfilamentation and biofilm formation. Our study links a single heterozygous mutation to the ability of C. albicans to better survive during the interaction with other CF-associated microbes and illuminates how adaptive traits emerge in microbial pathogens to persistently colonize and/or infect the CF-patient airways.

Primary ciliary dyskinesia gene contribution in Tunisia: Identification of a major Mediterranean allele.

Primary ciliary dyskinesia (PCD) is a genetically heterogeneous disease of motile cilia. Even though PCD is widely studied, North-African patients have been rarely explored. In this study, we aim at confirming the clinical diagnosis and explore the genetic spectrum of PCD in a cohort of Tunisian patients. Forty clinically diagnosed patients with PCD belonging to 34 families were recruited from Tunisian pediatric departments. In each proband, targeted capture PCD panel sequencing of the 40 PCD genes was performed. PCD panel sequencing identified bi-allelic mutations in 82% of the families in eight PCD genes. Remarkably, 23.5% of patients carried the same c.2190del CCDC39 mutation. Single nucleotide polymorphism profiling in six unrelated patients carrying this mutation has revealed a founder effect in North-African patients. This mutation is estimated to date back at least 1,400-1,750 years ago. The identification of this major allele allowed us to suggest a cost-effective genetic diagnostic strategy in North-African patients with PCD.

A Novel Mutation c.153 C>A in a Tunisian Girl With Wolman Disease and Unusual Presentation: Hemophagocytic Lymphohistiocytosis.

Wolman disease is an ultrarare lysosomal storage disease caused by a mutation in the LIPA gene. The clinical features of Wolman disease include early onset of vomiting, diarrhea, failure to thrive, hepatosplenomegaly, and bilateral adrenal calcification. We report the case of a 3-month-old infant who presented clinical features of hemophagocytic lymphohistiocytosis. Genetic sequence analysis of the LIPA gene revealed homozygous mutation c.153 C>A (p.Tyr51*). The parents were heterozygous for this mutation. Prenatal diagnosis has been carried out in the next pregnancy. To our knowledge, this mutation has never been reported before, and this is an unusual case of secondary hemophagocytic lymphohistiocytosis complicating Wolman disease.

Correction to: Full title: peripheral venous catheter complications in children: predisposing factors in a multicenter prospective cohort study.

Following publication of the original article [1], one of the authors flagged that the title of the article was submitted (incorrectly) with "Full title:" at the beginning.

Influenza A/H1N1 pdm 09 in children's Hospital Bechir Hamza of Tunis.

BACKGROUND: Influenza A (H1N1) is a contagious acute respiratory infection caused a pandemic in 2009. The outcome was variable among populations. AIM: To describe a clinical spectrum and the outcome of Tunisian children with pandemic H1N1/09 influenza virus. METHODS: This is a retrospective, descriptive study of children with pandemic H1N1/09 influenza virus hospitalized in the children's hospital of tunis, between November 2009 and February 2010. The diagnosis was made on positive rapid test or PCR. RESULTS: thirty two children were included. The median age was 12 months. The most frequently symptoms were: fever (87,5%), digestive disorders ( 59,4%) and dyspnea (15,6%). The mean length of stay was 3,8 days. The outcome was complicated by a bacterial infection (56,3%), and one death. CONCLUSION: Mild form of H1N1/influenza virus is the most common presentation; however severe forms can be observed especially in infants.

Peripheral venous catheter complications in children: predisposing factors in a multicenter prospective cohort study.

BACKGROUND: Peripheral venous catheterization (PVC) is frequently used in children. This procedure is not free from potential complications. Our purpose was to identify the types and incidences of PVC complications in children and their predisposing factors in a developing country. METHODS: We conducted a prospective observational multicenter study in five pediatric and pediatric surgery departments over a period of 2 months. Two hundred fifteen PVC procedures were conducted in 98 children. The times of insertion and removal and the reasons for termination were noted, and the lifespan was calculated. Descriptive data were expressed as percentages, means, standard deviations, medians and interquartile ranges. The Chi2 test or the Fisher test, with hazard ratios and 95% confidence intervals (CI95%), as well as Student's t test or the Mann-Whitney U test were used to compare categorical and quantitative variables, respectively, in groups with and without complications. The Spearman test was used to determine correlations between the lifespan and the quantitative variables. The Kruskal Wallis test was used to test for differences in the median lifespan within 3 or more subgroups of a variable. Linear regression and logistic binary regression were used for multivariate analysis. A p-value <0.05 was considered significant. RESULTS: The mean lifespan was 68.82 ± 35.71 h. A local complication occurred in 111 PIVC (51.9%) cases. The risk factors identified were a small catheter gauge (24-gauge) (p = 0.023), the use of a volume-controlled burette (p = 0.036), a longer duration of intravenous therapy (p < 0.001), a medical diagnosis of respiratory or infectious disease (p = 0.047), the use of antibiotics (p = 0.005), including cefotaxime (p = 0.024) and vancomycin (p = 0.031), and the use of proton pump inhibitors (p = 0.004).The lifespan of the catheters was reduced with the occurrence of a complication (p < 0.001), including the use of 24-gauge catheters (p = 0.001), the use of an electronic pump or syringe(p = 0.036) and a higher rank of the intravenous device in each patient (p = 0.010). CONCLUSIONS: PVC complications were frequent in our pediatric departments and are often associated with misuse of the device. These results could engender awareness among both doctors and nurses regarding the need for rationalization of the use of PVC and better adherence to the recommendations for the use of each drug and each administration method.

Community-acquired pleuropneumonia in children: Bacteriological and therapeutic challenges.

Background Community-acquired pleuropneumonia (CPP) is a common complication of pneumonia in children. It is serious given its high morbidity and significant mortality. Aim To study clinical and paraclinical features of CPP in children and to establish a common therapeutic strategy. Methods Our retrospective study included patients who were hospitalized for CPP between 2004 and 2012. All data were collected from patients' medical files. Statistical analysis was made by Epi-Info 6. Results One hundred and sixty four patients were registered. The mean age was 32 months (15 days - 14.5 years). The hospital incidence of CPP doubled between 2004 and 2012. The symptomatology was dominated by fever (93.9%), cough (56.7%) and dyspnea (48.1%). The pleural effusion was frequently moderately abundant and loculated. Pleural sample, performed in 53.6% of cases, was the most beneficial bacteriological examination (p=10-6 ). The bacteriological confirmation was attained in 44.5% of cases with the predominance of Staphylococcus aureus (59%) followed by Streptococcus pneumoniae (26%). The S. aureus occurred basically in most young infants (p=0.04) and was responsible for the most severe cases (p=0.01). The CPP management included heterogeneous intravenous antibiotics associated with a pleural drainage in 40% of cases. The quarter of our patients were transferred to an intensive care unit. Six patients died. Conclusion The bacteriological confirmation is difficult. Pleural aspiration is the key tool. S. aureus is the first microorganism followed by S. pneumoniae. A therapeutic strategy is proposed based on large spectrum intravenous antibiotics. The pleural drainage indication is limited.

Report of the Tunisian Registry of Primary Immunodeficiencies: 25-Years of Experience (1988-2012).

PURPOSE: Primary immunodeficiencies (PIDs) are a large group of diseases characterized by susceptibility to not only recurrent infections but also autoimmune diseases and malignancies. The aim of this study was to describe and analyze the distribution, clinical features and eventual outcome of PID among Tunisian patients. METHODS: We reviewed the record of 710 patients diagnosed with Primary Immunodeficiency Diseases (PIDs) from the registry of the Tunisian Referral Centre for PIDs over a 25-year period. RESULTS: The male-to-female ratio was 1.4. The median age at the onset of symptoms was 6 months and at the time of diagnosis 2 years. The estimated prevalence was 4.3 per 100,000 populations. The consanguinity rate was found in 58.2 % of families. According to the International Union of Immunological Societies classification, spectrums of PIDs were as follows: combined T-cell and B-cell immunodeficiency disorders account for the most common category (28.6 %), followed by congenital defects of phagocyte (25.4 %), other well-defined immunodeficiency syndromes (22.7 %), predominant antibody deficiency diseases (17.7 %), diseases of immune dysregulation (4.8 %), defect of innate immunity (0.4 %) and complement deficiencies (0.4 %). Recurrent infections, particularly lower airway infections (62.3 %), presented the most common manifestation of PID patients. The overall mortality rate was 34.5 %, mainly observed with combined immunodeficiencies. CONCLUSION: The distribution of PIDs was different from that reported in Western countries, with a particularly high proportion of Combined Immunodeficiencies and phagocyte defects in number and/or function. More is needed to improve PID diagnosis and treatment in our country.

A randomized, controlled trial of nebulized 5% hypertonic saline and mixed 5% hypertonic saline with epinephrine in bronchiolitis.

BACKGROUND: Bronchiolitis is a public health problem in the word and in Tunisia. Nebulized hypertonic saline seems to have some benefits in bronchiolitis. The aim of this study is to evaluate the efficacy of nebulized 5% hypertonic saline alone or mixed with epinephrine in bronchiolitis as measured by improvement in clinical score, oxygen saturation or reduction in duration of hospitalization. METHODS: This prospective, double blind, placebo controlled, randomized clinical trial was performed at Children's Hospital of Tunis from February 2012 to Mars 2012. A total of 94 patients less than 12 months of age with diagnosis of moderately severe bronchiolitis were enrolled and assigned to receive 5% nebulized hypertonic saline, mixed 5% hypertonic saline with standard epinephrine 0,1% or normal saline (placebo) at admission and every 4 hours during hospitalization. RESULTS: There were no significant difference between nebulized 5% hypertonic saline, mixed 5% hypertonic saline with epinephrine or normal saline at baseline, T30 min, T60 min, and T120 min after start study in Wang severity score, oxygen saturation in room air, rate respiratory and heart rate. There was no difference in duration of hospitalization. CONCLUSION: Nebulized 5% hypertonic saline or mixed 5% hypertonic saline with epinephrine are safety but does not appear effective in treating moderately ill infants with the first acute bronchiolitis.

[Skin sensitization to aeroallergens in the child: cross-sectional study of 200 cases]. / Les sensibilisations cutanées aux pneumallergies chez l'enfant: etude transversale de 200 cas.

BACKGROUND: The prevalence of the allergic diseases increased considerably during the last decades. The clinical expression of allergy depends on the interaction of genetic and environmental factors. AIM: The aim of our study was to evaluate the prevalence of sensitizing to aeroallergens in the child and to determine the risk factors of sensitizing. METHODS: We carried out a cross-sectional study relating to 200 pediatric patients of the Mahmoud El Matri hospital, aged from 3 to14 years. We performed skin prick test to 12 current aeroallergens. RESULTS: The prevalence of sensitizing to aeroallergens was 14%. Acarina (DP and/or DF) represented the allergens accused in the majority of the cases (96,4% of the cases). The statistical analysis of the various risk factors of sensitizing showed that these factors were: the presence of a family atopy (p= 0,0034) particularly a maternal asthma (p< 0,001), the personal atopy specially an asthma, an allergic rhinitis or eczema atopic (p< 10-5), the short breast-feeding (p= 0,033) and the home humidity (p=0,0072). Several risk factors reported in the literature did not seem to intervene in our study (the passive smoking, the urban dweling, the age of food diversification, infections at the low age). CONCLUSION: The prevalence of sensitizing to aeroallergens is relatively high in our series. Many factors could explain the increase of the allergic diseases. Our study stresses the importance of the genetic, nutritional and environmental factors in the appearance of aeroallergens sensitization.

Difficulties in the treatment of an infant survivor with inherited surfactant protein-B deficiency in Tunisia.

A female-term neonate showed a severe respiratory distress syndrome (RDS) at hour 3 of life requiring her transfer to intensive care. She was intubated and started on assist-control mechanical ventilation associated with inhaled nitric oxide then high-frequency oscillation ventilation at day 12. Chest X-ray was gradually deteriorating. Chest computed tomography (CT) scan revealed diffuse interstitial lung disease. Flexible bronchoscopy excluded pulmonary alveolar proteinosis. The genetics study confirmed surfactant protein-B (SP-B) deficiency caused by the novel homozygous c.770T>C, p.Leu257Pro mutation in the SFTPB gene (NM_000542.5). Methylprednisolone pulse therapy was administered from day 20. As the infant worsened, azithromycin, sildenafil, and inhaled steroids were added at the age of 6 months and azathioprine at the age of 10 months. At the age of 12 months, chest CT showed diffuse "crazy-paving." The infant died of respiratory failure at the age of 13 months. Unexplained neonatal RDS should raise the suspicion of SP-B disease. This novel mutation could be part of the mutations allowing partial SP-B production result in prolonged survival. Lung transplant in infants, unavailable in numerous countries, remains the unique way to reverse the fatal outcome.

A case report of inherited surfactant protein deficiency: unknown cause of diffuse infiltrative diseases in Tunisia.

INTRODUCTION: Children's Interstitial Lung Diseases (cHILD) are a heterogeneous group of rare respiratory diseases. Their common characteristics are gas exchange abnormalities and diffuse pulmonary infiltrates on chest imaging. This group includes inherited surfactant protein deficiency (ISPD), a little-known etiology in Tunisia. CASE PRESENTATION: A 22-month-old boy was referred to investigate recurrent respiratory infections. He had polypnea, cyanosis, finger clubbing, pectus carinatum, intercostal retraction, and bilateral crackles on pulmonary auscultation. The chest imaging revealed a diffuse ground-glass appearance consistent with cHILD. Lung biopsy was suggestive of ISPD. The infant was mainly treated with intravenous corticosteroids. At the age of nine, he was still dependent on oxygen but had better exercise tolerance. CONCLUSION: This case showed that recurrent respiratory infections can hide cHILD which may be related to ISPD, particularly in infants. A better knowledge of this disease was necessary to start specific treatment. Early management would lead to better prognosis.

[Haemophilus influenzae type B (Hib) meningitis in older children: about a case]. / Méningo-encéphalite à Haemophilus influenzae type b chez le grand enfant: à propos d'un cas.

Since widespread vaccination, invasive Haemophilus influenzae type b (Hib) has become a rare infection. We here report the case of a 9-year-old boy admitted with seizures associated with fever and impaired general condition. First examination showed comatose child, Glasgow score 9/15, fever 38.2, deep tendon reflexes without frank meningeal syndrome. Laboratory tests showed polymorphonuclear neutrophils (PNN) with CRP 45.8. Cerebrospinal fluid (CSF) analysis revealed a cloudy appearance, pleiocytosis (6760 white blood cell count/ mm3) with neutrophil predominance (PNN = 90%, lymphocytes = 10%). Direct examination showed polymorphic bacilli, soluble antigen of Haemophilus influenzae type b, decreased glycorachy 0.04 mmol/L and hyper proteinorachie 4.097 g/L. MRI of the cerebellomedullary fissure revealed subtentorial and supratentorial encephalitis with bilateral parieto-occipital and cerebellar cortical and subcortical signal anomalies. The patient was treated with cefotaxime with favorable outcome. The patient had not been vaccinated against Hib in early childhood. After a 3-year follow-up, the patient was asymptomatic with no neurosensory sequelae. In subjects with severe Hib infection proof of vaccination or testing for underlying immunodeficiency are required.

Variable Expression of Lung Disease Due to a Novel Homozygous ABCA3 Variant.

Background: Mutations in the ATP-binding cassette transporter A3 (ABCA3) gene are one of the most common surfactant disorders leading to interstitial lung diseases (ILD). The clinical spectrum and severity of lung disease caused by ABCA3 deficiency due to missense variants is variable. Case Presentations: A novel ABCA3 c.3135G>C (p.Gln1045His) mutation was identified at the homozygous state in 3 subjects from 2 unrelated families: one 19-month-old boy with severe ILD and his homozygous pauci-symptomatic mother, and one 10-year-old girl with moderate late-onset ILD. Corticosteroid pulses associated with hydroxychloroquine were beneficial for both children. Conclusion: We illustrate here the huge intra- and interfamilial phenotypic variability associated with the same homozygous missense ABCA3 mutation, and the benefit of identifying the disease for treatment, follow-up, and appropriate genetic counseling.

Acute bronchiolitis management in Tunisia: Impact of the national guidelines.

BACKGROUND: Acute bronchiolitis management involves all pediatricians and primary care physicians. The national guidelines for bronchiolitis diagnosis and treatment were published in Tunisia to reduce excessive use of diagnostic tests and unify bronchiolitis management. OBJECTIVES: We aimed to assess the real impact of the national guidelines on acute bronchiolitis management in Tunisia. METHODS: We conducted an evaluative cross-sectional study. We randomly distributed anonymous questionnaires to physicians managing acute bronchiolitis during the period from 1st March 2014 to 30 November 2015. RESULTS: We analyzed 140 questionnaires. Ninety-three interviewed physicians (66.4%) were advised of the latest national guidelines, half of them (33.6%) declared they didn't follow these guidelines. Real and complete guidelines adherence was observed in only 1.4% of interviewed physicians. According to bronchiolitis diagnosis, appropriate Chest X-rays and blood tests were requested respectively by 57.8% and 59.3% of interviewed doctors. Regarding bronchiolitis therapeutic management, bronchodilators and epinephrine nebulization weren't prescribed by respectively 45.7% and 38.6% of them. Antibiotics were prescribed by 92.9% of interviewed doctors and chest physiotherapy was well indicated by 47.8% of them. CONCLUSIONS: There is a disconnect between the bronchiolitis guidelines and clinical practice. National strategies have to be developed to reduce excessive use of diagnostic tests and unrecommanded therapies.

Abdominal tuberculosis in children.

BACKGROUND: Abdominal tuberculosis (TB) includes infection of the gastrointestinal tract, peritoneum, mesentery, abdominal lymph nodes, liver, spleen, and pancreas. The most common forms of abdominal TB in children are adhesive peritonitis and nodal disease. PATIENTS AND METHODS: We report our experience with abdominal TB treated in our hospital from 1995 to 2008. RESULTS: Thirteen patients (3 boys and 10 girls) of mean age 9.8 years were diagnosed as having abdominal TB. Eight patients presented with abdominal distension and abdominal pain. Fever was seen in 4 patients. One patient had surgical abdominal pain and 2 had abdominal mass. Two patients had coexisting pleural effusion and 1 of them had multifocal TB. Abdominal TB involved peritoneum in 9, abdominal lymph nodes in 7, gastrointestinal tract in 3, spleen in 2 patients, and liver in 1. Ascitic fluid analysis of 9 patients showed exudative fluid with predominately lymphocytes. Laparotomy was performed in 3 patients. The diagnosis of abdominal TB was confirmed histopathologically in 5 patients and microbiologically in 3. The remaining patients had been diagnosed by ascitic fluid diagnostic features, abdominal imaging, tuberculin skin test, history of exposure, and a positive response to antituberculous treatment. Twelve patients completed the antituberculous therapy without any complications. One patient with multifocal TB had neurological sequelae. CONCLUSIONS: In the areas with a high prevalence of tuberculosis and confirmatory investigations are inadequately available, treatment may be initiated, based on strong clinical diagnosis and supportive investigations. In such situations, it is the response to therapy that indirectly proves the diagnosis.

Congenital salivary gland anlage tumor of the nasopharynx.

Nasal and upper respiratory tract obstruction in the neonatal period can result from a variety of conditions, and may be present with variable symptoms. Salivary gland anlage tumor, also referred as congenital pleomorphic adenoma, is a very rare benign congenital tumor of the nasopharynx, which may produce nasal obstruction and other associated, nonspecific symptoms. We report a case of congenital salivary gland anlage tumor causing a severe neonatal respiratory distress with pulmonary hypertension. The tumor was removed and the outcome was favourable without recurrence at five years of the follow up.

Mediastina Tuberculosis mass in a three-month-old boy.

BACKGROUND: Mediastinal mass of tuberculous origin is exceedingly rare in infant. AIM: to report an exceedingly rare case of mediastinal mass of tuberculous origin. CASE REPORT: We report a three-month-old boy who presented a one month history of wheezing and persistent pneumopathy. Radiological investigations showed a large posterior mediastinal mass which infiltrates lungs. Thoracoscopic biopsy showed caseous necrosis with granuloma suggestive of tuberculosis. The outcome was favourable with antituberculous chemotherapy. CONCLUSION: Mediatinal mass of tuberculous origin should considered in differential diagnosis of mediastinal masses in children; be suggested in mediastinal mass in children.

Congenital cutaneous candidiasis associated with respiratory distress in a full-term newborn.

BACKGROUND: Congenital candidiasis is rare occurring in most cases in premature and low birth weight new born. It can produce a spectrum of disease ranging from a diffuse skin eruption to a severe systemic disease with or without skin involvement. Amphotericin B is the first-line agent for the treatment of systemic disease. AIM: To describe a congenital candidiasis in a full-term newborn. CASE REPORT: At birth, the newborn had a generalized, erythematous, papulovesicular eruption. He was treated by topic antifungal therapy. However, on the third day, he developed a systemic disease with respiratory distress and fever. Ear, skin swab and gastric aspirate grew to Candida albicans. The newborn was given fluconazole for 10 days with favourable outcome. CONCLUSION: Early topic therapy did not prevent systemic spread of congenital cutaneous candidiasis in our case. Treatment with fluconazole, as the first-line agent, seems effective and safe.

[Role of lumbar puncture for febrile seizure among infants under one year old]. / L'utilité de la ponction lombaire en cas de convulsion fébrile chez le nourrisson agé de moins d'un an.

BACKGROUND: Febrile seizure is a frequent cause of hospitalization. Its management remains problematic. According to the American Academy of Pediatrics, lumbar puncture, which is not devoid of risk, is strongly recommended in infants under 1 year. AIM: to define the utility of lumbar puncture in the management of febrile seizures in infants under 12 months and to identify risk factors of meningitis and to respond to this question: "lumbar punction should be done in which infant with febrile seizure?" PATIENTS AND METHODS: This retrospective study was conducted in the department of pediatrics B in the Children Hospital of Tunis on eight-year period (2000-2008). In all statistical tests, significance level was set at 0.05. RESULTS: One hundred and six cases were collected during the period of study. Seizures related to bacterial meningitis were seen in 11 cases (10%). We have separated two groups: GI infants presented bacterial meningitis, and G2 infants with febrile seizure. The comparison between the two groups G1 and G2 showed the following predictors factors of meningitis: age < or = 7 months (p = 0.035), partial seizure (p = 0.028), duration of seizure > 5 min (p < 0.001), recurrence of seizure in the same day(p = 0,006), neurological abnormalities p < 0.001), CRP > 20 mg/l (p = 0.03), hyponatremia < or = 125 mmol/l (p = 0.01). The risk of meningitis is very low: 3.1 x 10 -3, if this condition is met: infants older than 7 months, having a unique and short seizure < or = 5 min, and with a CRP < or = 20mg/l. CONCLUSION: If the infant is older than 7 months, presenting a unique, febrile and short (< or = 5 min) seizure, having a normal neurological examination with CRP < or = 20 mg/l, lumbar puncture should be discussed a case by case but an hospitalization for 24 hours is required for monitoring.