Fabio Cardinale

Emergence of macrolide-resistant strains during an outbreak of Mycoplasma pneumoniae infections in children

OBJECTIVES Mycoplasma pneumoniae is a frequent cause of human lower respiratory tract infections (LRTIs) for which macrolides are the treatment of choice. The aim of this study was to determine the rate of macrolide resistance and to subtype M. pneumoniae strains in Italy. PATIENTS AND METHODS During an outbreak of M. pneumoniae infections in southern Italy in 2010, 48 clinical specimens from 43 paediatric patients hospitalized for LRTIs were analysed for macrolide resistance. The mutations associated with resistance (A2063G and A2064G) and M. pneumoniae subtypes were detected by sequencing the targeted domain V region of the 23S rRNA gene and a region in the MPN528a gene, respectively. RESULTS Macrolide resistance genotypes were detected in 11 (26%) of the 43 M. pneumoniae-positive children. The A2063G mutation was identified in seven patients and the A2064G mutation was identified in the remaining four. Upon admission, the isolates from three patients showed a susceptible genotype but subsequently acquired the A2063G mutation. Genotyping revealed M. pneumoniae subtype 1 in 33 of 40 sequenced strains and subtype 2 in the remaining 7. There was no association between macrolide resistance or susceptibility and the M. pneumoniae subtypes. CONCLUSIONS This is the first report of macrolide resistance among M. pneumoniae strains in Italy. Our findings indicate an unexpected high prevalence of macrolide resistance genotypes in children, and so macrolide resistance should be carefully considered in patients who do not respond appropriately to antibiotic treatment. The epidemiological monitoring of macrolide resistance has become necessary in Italy and in the rest of Europe.

Exhaled nitric oxide, total serum IgE and allergic sensitization in childhood asthma and allergic rhinitis

Exhaled nitric oxide (eNO) levels are correlated with several markers of atopy and inflammatory activity in the airways, but the relationship between eNO and total serum IgE has not been fully elucidated in the context of allergic sensitization. The aim of this study was to investigate the relationship between eNO, total serum IgE and allergic sensitization in childhood asthma and allergic rhinitis. eNO levels, lung function, skin prick tests and total serum IgE were determined in 109 children (mean age, 10.4 yr) with mild intermittent asthma and in 41 children (mean age, 10.1 yr) with allergic rhinitis; 25 healthy non‐atopic children were recruited as controls. eNO levels (median) were significantly higher in patients with asthma (22.7 p.p.b.) and in those with allergic rhinitis (15.3 p.p.b.) than in healthy controls (5.9 p.p.b.). Children with allergic asthma had higher eNO levels than children with allergic rhinitis. A significant positive correlation was found between eNO and total serum IgE (asthma, r = 0.42, p < 0.0001; allergic rhinitis, r = 0.31, p < 0.01), and between eNO and the number of positive skin prick tests (asthma, r = 0.31, p < 0.0001; allergic rhinitis, r = 0.39, p < 0.01). eNO levels were better correlated with total IgE than with the number of positive skin prick tests. This correlation was independent of allergic sensitization. High total serum IgE represents a specific and predictive marker of eNO increase in children with asthma or allergic rhinitis. This finding adds further support to the hypothesis that increased serum IgE could be a marker itself of airway inflammation in patients with allergic disease.

Efficacy of 1.25% and 1% topical cyclosporine in the treatment of severe vernal keratoconjunctivitis in childhood

Cyclosporine eyedrops 2% have been used for treatment of corticosteroid‐resistant vernal keratoconjunctivitis (VKC) cases. The purpose of our study was to verify the efficacy of 1.25% vs. 1% topical cyclosporine in improving severe form of VKC in childhood. Twenty children with severe VKC, were enrolled in a double‐blind, placebo‐controlled study and received cyclosporine 1.25% in one eye for 2 wk. Then an open trial was conducted during the next 3 months and 2 wk. Thirty‐two more patients were recruited the next year into a new open trial and they received cyclosporine 1% for 4 months. Ocular subjective symptoms and objective signs were scored in all children at entry, 2 wk and 4 months. Skin prick tests and conjunctival scraping tests were also performed; serum immunological and biochemical markers were assessed. The mean score values for severity of subjective symptoms and objective signs were significantly decreased after 2 wk, and 4 months, compared with those at entry (p < 0.001), in both groups of children who received cyclosporine eyedrops 1.25% and 1%, respectively. Serum markers did not differ from the beginning to the end of treatment. Conjunctival eosinophils and cyclosporine serum levels were not detectable at the end of therapy, nor were endothelial corneal cells damaged. Our findings suggest that 1% cyclosporine concentration might be the minimal effective treatment regimen to control symptoms and local inflammation in severe forms of VKC.

Risk factors for severe pediatric food anaphylaxis in Italy.

To cite this article: Calvani M, Cardinale F, Martelli A, Muraro A, Pucci N, Savino F, Zappalà D, Panetta V, the Italian Society of Pediatric Allergy and Immunology (SIAIP) anaphylaxis’ study group. Risk factors for severe pediatric food anaphylaxis in Italy. Pediatr Allergy Immunol 2011: 22: 813–819.

Clinical Features and Follow-Up in Patients with 22q11.2 Deletion Syndrome.

OBJECTIVE To investigate the clinical manifestations at diagnosis and during follow-up in patients with 22q11.2 deletion syndrome to better define the natural history of the disease. STUDY DESIGN A retrospective and prospective multicenter study was conducted with 228 patients in the context of the Italian Network for Primary Immunodeficiencies. Clinical diagnosis was confirmed by cytogenetic or molecular analysis. RESULTS The cohort consisted of 112 males and 116 females; median age at diagnosis was 4 months (range 0 to 36 years 10 months). The diagnosis was made before 2 years of age in 71% of patients, predominantly related to the presence of heart anomalies and neonatal hypocalcemia. In patients diagnosed after 2 years of age, clinical features such as speech and language impairment, developmental delay, minor cardiac defects, recurrent infections, and facial features were the main elements leading to diagnosis. During follow-up (available for 172 patients), the frequency of autoimmune manifestations (P = .015) and speech disorders (P = .002) increased. After a median follow-up of 43 months, the survival probability was 0.92 at 15 years from diagnosis. CONCLUSIONS Our data show a delay in the diagnosis of 22q11.2 deletion syndrome with noncardiac symptoms. This study provides guidelines for pediatricians and specialists for early identification of cases that can be confirmed by genetic testing, which would permit the provision of appropriate clinical management.

A prospective study on children with initial diagnosis of transient hypogammaglobulinemia of infancy: results from the Italian Primary Immunodeficiency Network.

Transient hypogammaglobulinemia of infancy (THI) is a heterogenous disorder characterized by reduced serum IgG levels in early infancy. A putative diagnosis is initially made after exclusion of other causes of hypogammaglobulinemia while a definitive diagnosis of THI can only be made a posteriori in patients with normalization of IgG levels. The aim of this study is to characterize clinical and immunological features of children with an initial diagnosis of THI in correlation to natural outcome, and to assess predictive laboratory parameters of clinical evolution for this disorder. We prospectively analysed clinical and immunological characteristics of 77 THI children at initial diagnosis and of 57 patients at follow-up. Memory B cell subsets and in vitro immunoglobulin production were evaluated. Seventy patients (91%) showed clinical symptoms. Patients suffered from infections (91%), allergies (47%) and autoimmune disease (4%). During follow-up 41/57 children (72%) normalized IgG values, mostly within 24 months of age (p<0.001), allowing the diagnosis of THI. The 16 children who did not normalize their IgG levels showed a higher frequency of severe infections and autoimmune disease (p<0.01). Moreover, they expressed a reduced frequency of IgM and switched memory B cells (p<0.01) and an inability to produce IgG in vitro (p<0.02). We conclude that most patients with an initial diagnosis of THI spontaneously recover within 24 months of age and have a benign clinical course, while a subgroup of children with undefined hypogammaglobulinemia share a clinical and immunological profile with other primary immunodeficiencies. Early recognition of children with hypogammaglobulinemia during infancy who are likely to suffer from permanent immunodeficiencies later in life would allow prompt and appropriate laboratory and clinical interventions.

Mutations of the X-linked lymphoproliferative disease gene SH2D1A mimicking common variable immunodeficiency

Abstract. Common variable immunodeficiency (CVID) and X-linked lymphoproliferative (XLP) disease are two immunodeficiencies that may share a similar immunological phenotype making differential diagnosis difficult. We report two patients initially diagnosed as affected with CVID who, using molecular analysis, have been subsequently found to be affected with XLP disease. Distinguishing between these two diseases is essential since they have different prognosis, treatment and genetic counselling. Conclusion: current techniques, such as genetic analysis of the SH2D1A gene and expression of signalling lymphocyte activation molecule-associated protein, allow a definite diagnosis of X-linked lymphoproliferative disease.

Pulmonary and sinus diseases in primary humoral immunodeficiencies with chronic productive cough.

Aims: To prospectively evaluate sinopulmonary disease in 24 patients with primary humoral immunodeficiency (11 with agammaglobulinaemia, nine with isolated IgA deficiency, and two with common variable immunodeficiency) and chronic productive cough, ascertain the usefulness of chest high resolution computed tomography (HRCT) in evaluating the progression of lung disease, and test a therapeutic approach to chronic sinusitis. Methods: Pulmonary abnormalities were evaluated using lung function tests and HRCT (Bhalla score); chronic sinusitis was diagnosed clinically and confirmed by flexible fibreoptic endoscopy. Sixteen patients entered the three year follow up. Results: Lung function testing revealed an obstruction in four patients; chest HRCT was abnormal in 16. There was a linear relation between the Bhalla score ⩾4 and the number of months with cough/year over the previous two years (clinical score), and between the difference in clinical scores during follow up and in the previous two years and the difference in Bhalla score. The pulmonary lesions did not significantly progress over a three year period. Thirteen patients had chronic sinusitis; 6/10 patients followed up were successfully treated with antibiotics plus topical therapy and two with nasal polypoid disease with endoscopic sinus surgery. Conclusions: In patients with primary humoral immunodeficiency and chronic productive cough, HRCT is very useful in delineating the extent of lung damage. The correlation between Bhalla score and clinical findings and the favourable outcome of the disease suggests that in most patients chest HRCT should not be repeated annually as previously suggested. Medical therapy seems to be effective in many cases of chronic sinusitis.

Molecular analysis of the pre-BCR complex in a large cohort of patients affected by autosomal-recessive agammaglobulinemia.

Autosomal-recessive agammaglobulinemia is a rare and heterogeneous disorder, characterized by early-onset infections, profound hypogammaglobulinemia of all immunoglobulin isotypes and absence of circulating B lymphocytes. To investigate the molecular basis of the disease, 23 patients with early-onset disease and no mutations in Bruton tyrosine kinase, the gene responsible for X-linked agammaglobulinemia, were selected and analyzed by direct sequencing of candidate genes. Two novel mutations in the μ heavy chain (μHC) gene (IGHM) were identified in three patients belonging to two unrelated families. A fourth patient carries a previously described G>A nucleotide substitution at the −1 position of an alternative splice site in IGHM; here, we demonstrate that this mutation is indeed responsible for aberrant splicing. Comparison of bone marrow cytofluorimetric profiles in two patients carrying different mutations in the IGHM gene suggests a genotype–phenotype correlation with the stage at which B-cell development is blocked. Several new single nucleotide polymorphisms (SNPs) both in the μHC and in the λ5-like/VpreB-coding genes were identified. Two unrelated patients carry compound heterozygous variations in the VpreB1 gene that may be involved in disease ethiology.

Macrolide-resistant Mycoplasma pneumoniae in paediatric pneumonia

To the Editors: Mycoplasma pneumoniae is one of the most common causes of bacterial community-acquired pneumonia (CAP) in paediatrics, and can lead to severe and long-lasting disease [1]. Macrolides are usually considered the first-choice antimicrobials for M. pneumoniae CAP in children because the alternatives ( i.e. fluoroquinolones and tetracyclines) are not approved for use in the first years of life [2]. Recent studies from Japan and China have shown macrolide resistance in up to 80% of M. pneumoniae strains [3, 4], but it has been detected in relatively few cases in the USA, France and Germany, and not at all in other European countries [5–7]. The mechanism of M. pneumoniae macrolide resistance is related to point mutations in domain V of the 23S rRNA gene of M. pneumoniae and macrolide resistance is usually detected at disease onset [4]. We here describe the first case of macrolide-resistant M. pneumoniae detected during treatment with clarithromycin in an otherwise healthy child with CAP. An otherwise healthy 6-yr-old girl with an unremarkable medical history who had never travelled abroad was admitted in Bari, Italy, after suffering from a dry cough for 3 days with fever up to 40.5°C, accompanied by increasing malaise and dyspnoea. Upon admission, she was severely ill, with a high temperature, lethargy, an increased respiratory rate (60 breaths·min−1), tachycardia and normal blood pressure. Room air oximetry revealed 85% oxygen saturation, whereas arterial gas sampling showed severe hypoxaemia (50 mmHg) with hypocapnia and a normal pH. Other routine blood examinations revealed neutrophilia with increased C-reactive protein levels and a high erythrocyte sedimentation rate. A physical examination revealed diffuse crackles with reduced vesicular sounds on both lungs, and chest radiography showed an interstitial pattern with multiple “ground-glass” infiltrates. Blood, nasopharyngeal …