Rita Consolini

Features of children perinatally infected with HIV-1 surviving longer than 5 years. Italian Register for HIV Infection in Children

Children infected with HIV do not necessarily develop AIDS to a set pattern but can be divided into long-term and short-term survivors. We examined long-term survival in children perinatally infected with HIV-1. Out of a total of 624, we studied 182 children who survived longer than 5 years (long-term survivors [LTS]) and 120 children who died of HIV-1-related disease before 5 years (defined as short-term survivors [STS]). 28 (15%) LTS were symptomless (Centers for Disease Control [CDC] P-1 children). 154 (85%) had symptoms (CDC P-2). The proportion of LTS with less than 0.2 x 10(9)/CD4 cells per L was 24/116 (21%) at 61-72 months, rising to 11/26 (41%) at more than 96 months. On at least one occasion, p24 antigenaemia was observed in 112 (62%) LTS. Annual rate of CD4 cell loss was lower in LTS (25% [95% CI: 21-29]) than in STS (53% [45-60]) and in LTS symptomless or with solitary P-2A signs (17%; [13-21]) than in LTS with severe manifestations (30% [25-35]). A new outlook emerges. A substantial number of children do survive after early childhood; severe diseases; low CD4 cell numbers, and p24 antigenaemia do not necessarily preclude long-term survival. The study shows that a CD4 cell decrease early in life can be predictive of outcome.

Differentiating PFAPA syndrome from monogenic periodic fevers

OBJECTIVES: To analyze whether there were clinical differences between genetically positive and negative patients fulfilling periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis (PFAPA) syndrome criteria and to test the accuracy of the Gaslini diagnostic score for identifying patients with PFAPA syndrome with higher probabilities of carrying relevant mutations in genes associated with periodic fevers. METHODS: Complete clinical and genetic information was available for 393 children with periodic fever; 82 had positive genetic test results, 75 had incomplete genetic test results, and 236 had negative results for MVK, TNFRSF1A, and MEFV mutations. Current diagnostic criteria for PFAPA syndrome were applied. RESULTS: Of 393 children, 210 satisfied PFAPA syndrome criteria; 43 carried diagnostic mutations (mevalonate kinase deficiency: n = 33; tumor necrosis factor receptor-associated periodic syndrome: n = 3; familial Mediterranean fever: n = 7), 37 displayed low-penetrance mutations or incomplete genotypes, and 130 demonstrated negative genetic testing results. Genetically positive patients had higher frequencies of abdominal pain and diarrhea (P < .001), vomiting (P = .006), and cutaneous rash and arthralgia (P = .01). Genetically negative patients had a higher frequency of exudative pharyngitis (P = .010). Genetically undetermined patients showed the same pattern of symptom frequency as genetically negative patients. The Gaslini diagnostic score was able to identify 91% of genetically positive patients correctly, with a global accuracy of 66%. CONCLUSION: The Gaslini diagnostic score represents a useful tool to identify patients meeting PFAPA syndrome criteria and at low risk of carrying relevant mutations in genes associated with periodic fevers.

Diagnostics of Primary Immunodeficiencies through Next-Generation Sequencing

Background Recently, a growing number of novel genetic defects underlying primary immunodeficiencies (PIDs) have been identified, increasing the number of PID up to more than 250 well-defined forms. Next-generation sequencing (NGS) technologies and proper filtering strategies greatly contributed to this rapid evolution, providing the possibility to rapidly and simultaneously analyze large numbers of genes or the whole exome. Objective To evaluate the role of targeted NGS and whole exome sequencing (WES) in the diagnosis of a case series, characterized by complex or atypical clinical features suggesting a PID, difficult to diagnose using the current diagnostic procedures. Methods We retrospectively analyzed genetic variants identified through targeted NGS or WES in 45 patients with complex PID of unknown etiology. Results Forty-seven variants were identified using targeted NGS, while 5 were identified using WES. Newly identified genetic variants were classified into four groups: (I) variations associated with a well-defined PID, (II) variations associated with atypical features of a well-defined PID, (III) functionally relevant variations potentially involved in the immunological features, and (IV) non-diagnostic genotype, in whom the link with phenotype is missing. We reached a conclusive genetic diagnosis in 7/45 patients (~16%). Among them, four patients presented with a typical well-defined PID. In the remaining three cases, mutations were associated with unexpected clinical features, expanding the phenotypic spectrum of typical PIDs. In addition, we identified 31 variants in 10 patients with complex phenotype, individually not causative per se of the disorder. Conclusion NGS technologies represent a cost-effective and rapid first-line genetic approach for the evaluation of complex PIDs. WES, despite a moderate higher cost compared to targeted, is emerging as a valuable tool to reach in a timely manner, a PID diagnosis with a considerable potential to draw genotype–phenotype correlation. Nevertheless, a large fraction of patients still remains without a conclusive diagnosis. In these patients, the sum of non-diagnostic variants might be proven informative in future studies with larger cohorts of patients.

Prognostic significance of immunologic changes in 675 infants perinatally exposed to human immunodeficiency virus

Neutrophil, lymphocyte, and T-cell subset numbers and immunoglobulin levels were evaluated at birth to age 2 years in 675 children born to mothers infected with the human immunodeficiency virus type 1 (58 infected symptom-free subjects (P-1), 203 infected subjects with symptoms (P-2), and 414 uninfected subjects). The P-2 patients had (even at birth to age 1 month) lower CD4+ lymphocyte and higher IgA and IgM values than P-1 and uninfected children had. Increased IgG values (from 1 to 6 months of age) and increased CD8+ lymphocyte numbers (at 13 to 24 months of age) were also observed. The P-1 children differed from uninfected children only at 13 to 24 months of age (decreased CD4+ and increased CD8+ lymphocytes). Progressive immunologic changes were found in P-2 patients who had severe clinical conditions and in those who died. To evaluate the predictive meaning of the immunologic changes, we selected 164 children (25 P-2, 15 P-1, and 124 uninfected children) because they had been examined sequentially from birth and they were classified as in the indeterminate state of infection (P-0) at immunologic evaluations at birth to age 1 and at 1 to 6 months of age. During the 1- to 6-month period, P-2 patients had higher immunoglobulin and lower CD4+ lymphocyte values than P-1 and uninfected children had; no difference was found between P-1 and uninfected subjects. These results indicate that in infants with perinatal human immunodeficiency virus type 1 infection, immunologic abnormalities correlate with the clinical condition and are predictive of the clinical outcome rather than the infection status.

Comparison Study of MS-HRM and Pyrosequencing Techniques for Quantification of APC and CDKN2A Gene Methylation

There is increasing interest in the development of cost-effective techniques for the quantification of DNA methylation biomarkers. We analyzed 90 samples of surgically resected colorectal cancer tissues for APC and CDKN2A promoter methylation using methylation sensitive-high resolution melting (MS-HRM) and pyrosequencing. MS-HRM is a less expensive technique compared with pyrosequencing but is usually more limited because it gives a range of methylation estimates rather than a single value. Here, we developed a method for deriving single estimates, rather than a range, of methylation using MS-HRM and compared the values obtained in this way with those obtained using the gold standard quantitative method of pyrosequencing. We derived an interpolation curve using standards of known methylated/unmethylated ratio (0%, 12.5%, 25%, 50%, 75%, and 100% of methylation) to obtain the best estimate of the extent of methylation for each of our samples. We observed similar profiles of methylation and a high correlation coefficient between the two techniques. Overall, our new approach allows MS-HRM to be used as a quantitative assay which provides results which are comparable with those obtained by pyrosequencing.

Rapid disease progression in HIV-1 perinatally infected children born to mothers receiving zidovudine monotherapy during pregnancy The Italian Register for HIV Infection in Children*

OBJECTIVE To investigate the outcome in children perinatally infected with HIV-1 whose mothers received zidovudine (ZDV) monotherapy in pregnancy. DESIGN Observational retrospective study of a prospectively recruited cohort. SETTING Italian Register for HIV Infection in Children. PATIENTS A group of 216 children perinatally infected with HIV-1, born in 1992-1997 and derived prospectively from birth: 38 children had mothers receiving ZDV monotherapy and for 178 children the mothers received no antiretroviral treatment during pregnancy. MAIN OUTCOME MEASURES The estimated probability of developing severe disease or severe immune suppression, survival probability [95% confidence interval (CI)] within 3 years, and the hazard ratio (95% CI), adjusted for year of birth, maternal clinical condition at delivery, birthweight and treatments (Pneumocystis carinii pneumonia chemoprophylaxis and/or antiretroviral therapy before the onset of severe disease, severe immune suppression or death) were compared. RESULTS Comparison of HIV-1-infected children whose mothers were treated with ZDV with children whose mothers were not treated showed that the former group had a higher probability of developing severe disease [57.3% (95% CI 40.9-74.3) versus 37.2% (95% CI 30.0-45.4); log-rank test 7.83, P = 0.005; adjusted hazard ratio 1.8 (95% CI 1.1-3.1)] or severe immune suppression [53.9% (95% CI 36.3-73.5) versus 37.5% (95% CI 30.0-46.2); log-rank test 5.58, P = 0.018; adjusted hazard ratio 2.4, (95% CI: 1.3-4.3)] and a lower survival [72.2% (95% CI 50.4-85.7) versus 81.0% (95% CI 73.7-86.5); log-rank test 4.23, P = 0.039; adjusted hazard ratio of death 1.9 (95% CI 1.1-3.6)]. CONCLUSIONS This epidemiological observation could stimulate virologic studies to elucidate whether this rapid progression depends on in utero infection or transmission of resistant virus. Findings may suggest a need to hasten HIV-1 diagnosis in infants of ZDV-treated mothers and undertake an aggressive antiretroviral therapy in those found to be infected.

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.

Morpho-functional characterization of human mesenchymal stem cells from umbilical cord blood for potential uses in regenerative medicine

Mesenchymal stem cells (MSCs) represent a promising source of progenitor cells having the potential to repair and to regenerate diseased or damaged skeletal tissues. Bone marrow (BM) has been the first source reported to contain MSCs. However, BM-derived cells are not always acceptable, due to the highly invasive drawing and the decline in MSC number and differentiative capability with increasing age. Human umbilical cord blood (UCB), obtainable by donation with a noninvasive method, has been introduced as an alternative source of MSCs. Here human UCB-derived MSCs isolation and morpho-functional characterization are reported. Human UCB-derived mononuclear cells, obtained by negative immunoselection, exhibited either an osteoclast-like or a mesenchymal-like phenotype. However, we were able to obtain homogeneous populations of MSCs that displayed a fibroblast-like morphology, expressed mesenchym-related antigens and showed differentiative capacities along osteoblastic and early chondroblastic lineages. Furthermore, this study is one among a few papers investigating human UCB-derived MSC growth and differentiation on three-dimensional scaffolds focusing on their potential applications in regenerative medicine and tissue engineering. UCB-derived MSCs were proved to grow on biodegradable microfiber meshes; additionally, they were able to differentiate toward mature osteoblasts when cultured inside human plasma clots, suggesting their potential application in orthopedic surgery.

Enumeration of human peripheral blood dendritic cells throughout the life

Human aging is associated with immunosenescence, a process characterized by alterations in numerical and functional features of immune system components. Dendritic cells (DCs) are the main antigen-presenting cells, playing a pivotal role in adaptive and innate immunity. Therefore, we investigated the distribution of human circulating DCs throughout the life, in order to contribute to the knowledge of the physiological background underlying the aging of immune system. Cytofluorimetric analysis of peripheral blood samples by all-aged healthy population showed a significant decrease of circulating DCs and of their two main subsets among age. This reduction was limited to the plasmacytoid cell subtype when young and old subjects were analyzed separately. The analysis of circulating Treg cell number in a cohort of the subjects showed a significant reduction with increasing age and a positive significant correlation to myeloid or plasmacytoid absolute numbers. In conclusion, this work provides a large set of data of normal reference values of peripheral blood dendritic cells in healthy population suitable for comparative clinical studies concerning pathological immune dysfunctions.