Retrospective analysis of microorganisms isolated from cystic fibrosis patients in Southern Italy, 2002-2010.

OBJECTIVE: This study aim was to determine the prevalence of microorganisms in the respiratory tract of patients with cystic fibrosis (CF) admitted to the CF Reference Centre in Southern Italy between 2002-2010. METHODS: Microbiology assessment of samples (sputum and tracheal aspirates) collected from patients with pulmonary exacerbation admitted to hospital was carried out. All patients were registered in a database and clinical and microbiological data were retrospectively analysed. RESULTS: Overall, 188 patients were included and a total of 1217 samples were analysed. The most common microorganisms were Staphylococcus aureus (78.7% of the patients) and Pseudomonas aeruginosa (58%), followed by Candida albicans (19.1%), Haemophilus influenzae (13.3%) and Aspergillus fumigatus (9.6%). CONCLUSION: Compared to similar studies performed in other European countries, our microbiological data, especially the low occurrence of filamentous fungi, suggest a specific local epidemiology, probably related to some uncommon CFTR mutations, which are specific to Southern Italy.

Prevalence of atopic symptoms among blood donor carriers of mannose-binding lectin variant alleles.

Mannose-binding lectin (MBL) is a C-type soluble collectin involved in the innate immune response. Carriers of MBL gene variant alleles (MBLva) have decreased plasma concentrations of MBL and increased susceptibility to bacterial and viral infections. The aim of the present study is to test the hypothesis that carriers of MBLva could have a different frequency of atopic symptoms as compared to wild-type carriers. A total of 385 consecutively enrolled Caucasian blood donors were studied. Blood specimens underwent genomic analysis and genotyping for MBLva by polymerase chain reaction (PCR). MBLva carrier status was associated with a reduced frequency of allergic rhinitis (OR 0.41 [95% CI 0.2 to 0.8], chi2 = 6.98, p =.008). No relationship was found between MBLva carrier status and asthma or atopic skin symptoms. MBLva might be one of the host-related genetic factors involved in atopic disorders, namely allergic rhinitis.

Association of beta-defensin-1 gene polymorphisms with Pseudomonas aeruginosa airway colonization in cystic fibrosis.

Lung disease and Pseudomonas aeruginosa (P. aeruginosa) airway colonization represent a major cause of morbidity and mortality in cystic fibrosis (CF). Human beta-defensin (hBD)-1 is believed to play an important role in mucosal innate immunity in the lung. This study aimed to investigate whether three single-nucleotide polymorphisms (SNPs) in the 5'-untranslated region of DEFB1, G-52A, C-44G and G-20A were associated with P. aeruginosa airway colonization in CF. A total of 224 CF patients and 196 control subjects were studied. DEFB1 SNPs were characterized by restriction fragment length polymorphisms. Patients' sputum samples were collected and analyzed by standard methods. Single SNP analysis suggested that CF patients carrying the -52AA and the -20GG genotypes had a higher rate of P. aeruginosa airway colonization than patients homozygous and heterozygous for the -52G and -20A alleles (P=0.01 and P=0.007, respectively). A significant association between the ACG haplotype and chronic P. aeruginosa infection was also identified (odds ratio (95% confidence interval): 3.00 (1.42-6.36), P=0.004). These results indicate that variant alleles in DEFB1 might contribute to the colonization of P. aeruginosa in CF.

Comprehensive cystic fibrosis mutation epidemiology and haplotype characterization in a southern Italian population.

We screened the whole coding region of the cystic fibrosis transmembrane regulator (CFTR) gene in 371 unrelated cystic fibrosis (CF) patients from three regions of southern Italy. Forty-three mutations detected 91.5% of CF mutated chromosomes by denaturing gradient gel electrophoresis analysis, and three intragenic CFTR polymorphisms predicted a myriad of rare mutations in uncharacterized CF chromosomes. Twelve mutations are peculiar to CF chromosomes from southern Italy: R1158X, 4016insT, L1065P and 711 + 1G > T are present in 6.3% of CF chromosomes in Campania; G1244E and 852del22 are present in 9.6% of CF chromosomes in Basilicata and 4382delA, 1259insA, I502T, 852del22, 4016insT, D579G, R1158X, L1077P and G1349D are frequent in Puglia (19.6% of CF alleles). Several mutations frequently found in northern Italy (e.g., R1162X, 711 + 5G > T) and northern Europe (e.g., G551D, I507del and 621 + 1G > T) are absent from the studied population. The I148T-3195del6 complex allele was present in two CF chromosomes, whereas I148T was present in both alleles (as a single mutation) in another CF patient and in five CF carriers; this could result from crossover events. The haplotype analysis of three intragenic polymorphisms (IVS8CA, IVS17bTA and IVS17bCA) compared with data from other studies revealed that several mutations (3849 + 10kbC > T, 1717-1G > A, E585X, 3272-26G > A, L558S, 2184insA and R347P) originated from multiple events, whereas others (R1158X and S549R) could be associated with one or more intragenic recombinant events. Given the large population migration from southern Italy, knowledge of the CF molecular epidemiology in this area is an important contribution to diagnosis, counselling and interlaboratory quality control for molecular laboratories worldwide.

Liver expression in cystic fibrosis could be modulated by genetic factors different from the cystic fibrosis transmembrane regulator genotype.

During a multicentric study conducted in Southern Italy, we studied five sets of cystic fibrosis siblings bearing a strongly discordant liver phenotype, three with genotype DeltaF508/R553X, one with genotype DeltaF508/unknown, and one with genotype unknown/unknown. The siblings of each set were raised in the same family environment, and there were no interpair differences in nutritional state or in therapy compliance. All siblings had pancreatic insufficiency and moderate respiratory expression. One sibling of each of the five sets was free of liver involvement, and the other had severe liver expression. Other causes of liver disease (viral, metabolic, and genetic other than cystic fibrosis) were ruled out. Therefore, environmental factors, nutritional state, and therapy compliance are not involved in the liver expression of cystic fibrosis in the five unrelated sibships. This suggests that modifier genes, inherited independently of the cystic fibrosis transmembrane regulator gene, could modulate the liver expression in cystic fibrosis patients.

Prognostic relevance of ALL-1 gene rearrangement in infant acute leukemias.

We and others have recently reported a high frequency (70-80%) of ALL-1 (MLL, HRX, HTRX) gene rearrangements in infants with acute leukemias (AL) aged less than 1 year. Preliminary observations in limited series also suggested that ALL-1 gene configuration is an important prognostic factor in this leukemic subset. We have now extended our study to a series of 45 AL patients aged between 0 and 18 months. The genomic configuration of ALL-1 in leukemic DNAs was determined by Southern blot hybridization and correlated with biological and clinical features at presentation, as well as with treatment outcome. Twenty-nine out of 45 (64%) patients showed ALL-1 rearrangements, including 4/11 (36%) infants aged between 13 and 18 months. Considering morphological types, 24/38 cases with acute lymphoblastic leukemia and 5/7 patients with acute myeloid leukemia showed ALL-1 rearrangements. The features more frequently found in association with ALL-1 rearrangements were hyperleukocytosis (P < 0.007) and CD19+/CD10- blast immunophenotype (P < 0.02). ALL-1 status was an independent prognostic marker of event-free survival (EFS) in a multivariate model including age, sex and WBC count, and maintained its statistical significance when FAB morphology was considered in the analysis by including AML patients. Considering the ALL cases the actuarial EFS was 57 and 9% for infants with germline and rearranged ALL-1 configuration, respectively (P = 0.008). A high frequency of ALL-1 gene alterations in infant AL is confirmed by this study. In addition, our results emphasize the need for extending the analysis of ALL-1 gene status to infants with AL aged > 12 months. We show that this genetic lesion is the most important variable negatively affecting prognosis in a multivariate model including other known risk factors. This latter observation should influence the choice of risk-adapted treatment strategies in this AL subset.

Molecular variants of the 1;19 chromosomal translocation in pediatric acute lymphoblastic leukemia (ALL).

The t(1;19)(q23;p13), a non-random chromosome rearrangement associated with childhood pre-B acute lymphoblastic leukemia (ALL), results at molecular level in the hybrid E2A-PBX1 gene. This gene is expressed in a typical set of fusion transcripts and oncogenic chimeric proteins. However, the occurrence of t(1;19) molecular variants has been recently suggested. In an attempt to identify these variants, we analyzed 25 pediatric cases of pre-B cIg+ cell ALL. We used Southern blot analysis to detect E2A gene rearrangements and RT-PCR to detect chimeric E2A-pbx1 transcripts. In addition to seven cases with the molecular pattern usually associated with the t(1;19), we identified three molecular variants. In one case, a variant E2A-pbx1 transcript showed 27 additional base pairs inserted in frame at the junction site. In two cases, Southern blot evidenced the expected E2A gene rearrangements. However, extensive RT-PCR analysis failed to detect any E2A-pbx1 transcript. These findings led us to hypothesize that a gene other than PBX1 might be involved in these 1;19 variant translocations.

Lactate dehydrogenase isoenzyme patterns in blood cells from histiocytosis X children.

To find a clinical assay for histiocytosis X (HX) diagnosis, measurements were made of both activity and isoenzyme distribution of lactate dehydrogenase (LDH; EC 1.1.1.27) from the blood cells of 6 acute phase and 9 remission patients. A significant increase in the LDH activity measured in the monocytes and lymphocytes isolated from the blood of the acute phase patients was found. The increased activity was due to an enhancement of the normal pattern of LDH isoenzymes in these cells and not to a change in isoenzyme distribution. No increase was found in monocyte LDH isoenzymes from the patients in remission.

The immunophenotype in infant acute lymphoblastic leukaemia: correlation with clinical outcome. An Italian multicentre study (AIEOP).

A detailed analysis of immunophenotype of 112 infants aged less than 18 months with acute lymphoblastic leukaemia (ALL) was performed. Patients were divided into three groups on the basis of age at presentation (under 6 months: group 1: 6-12 months: group 2; 13-18 months: group 3). There were three cases of T-ALL (2.6%). The proportion of other subtypes was: common ALL in 59 patients (52.68%), pre-B ALL in 15 patients (13.3%), pre-pre-B ALL in 27 (24.1%) and acute undifferentiated leukaemia (AUL) in eight patients (7.14%). In non-T ALL, positivity to CD10 (corresponding to C-ALL and pre-B ALL) was distributed in the three age groups as follows: 38.88% (group I) 65.38% (group II) and 86.36% (group III). Conversely, immature phenotypes (pre-pre-B and AUL) were found more often in the younger patients of groups I and II, as well as anomalous phenotypes, such as the presence of myeloid antigens (MyAg) and of CD7. Prognostic significance was evaluated as event-free survival (EFS) by statistical analysis. A better outcome in CD10-positive ALL than in CD10-negative ones (48% v. 25% of long-term survivors) was demonstrated in all infants. Similarly, EFS was significantly better in MyAg-negative than in MyAg-positive cases. These results were confirmed also when adjusting for white blood cell count. This allowed the identification of CD10-negative, MyAg-positive ALL, which were relatively more frequent in infants and had a poorer clinical outcome with the current therapies. This study stresses the prognostic relevance of the immunological study in infant leukaemias and its utility in choosing different therapeutic modalities for poor risk phenotypes.

Angioimmunoblastic lymphadenopathy with dysproteinemia: report of a case in infancy with review of literature.

A case of angioimmunoblastic lymphadenopathy with dysproteinemia (AILD) in infancy is reported. The disease had a mild onset with generalized lymphadenopathy, hepatosplenomegaly, thrombocytopenia, polyclonal hypergammaglobulinemia, and T-cell deficiency. The AILD course lasted more than 100 months, alternating clinical remission to recurrent relapses. Hepatitis B viral infection suddenly evolving to hepatic failure was the cause of death. From a rapid survey of the present knowledge, the nosology, immunological features, and therapy of AILD are discussed and a possible presumptive pathogenetic pathway is proposed.