Outcome of primary hemophagocytic lymphohistiocytosis: a report on 143 patients from the Italian Registry.

Primary hemophagocytic lymphohistiocytosis (pHLH) is a severe, life-threatening hyperinflammatory syndrome caused by defects in genes of the granule-dependent cytotoxic pathway. Here we investigated the clinical presentation and outcome in a large cohort of 143 patients with pHLH diagnosed in the last 15 years and enrolled in the Italian registry. The median age at diagnosis was 12 months (IQR 2-81), and ninety-two patients (64%) fulfilled the HLH-2004 criteria. Out of 111 patients who received first-line combined therapy (HLH-94, HLH-2004, Euro-HIT protocols), 65 (59%) achieved complete response (CR) and 21 (19%) partial response (PR). Thereafter, 33 patients (30%) reactivated, and 92 (64%) received HSCT, 78 of whom (85%) survived and were alive at a median follow-up from diagnosis of 67 months. Thirty-six patients (25%) died before HSCT and 14 (10%) after. Overall, 93 patients (65%) were alive after a median follow-up of 30 months. Unadjusted predictors of non-response were age.

IgG4-related chronic sclerosing sialadenitis in a child with recurrent parotitis: a case report.

BACKGROUND: IgG4-related disease (IgG4-RD) includes a group of immune-mediated diseases histologically characterized by lymphoplasmacytic infiltrate with a prevalence of IgG4-positive plasma cells, storiform fibrosis and obliterative phlebitis. Autoimmune pancreatitis, sialadenitis, dacryoadenitis and retroperitoneal fibrosis are the most frequent manifestations. IgG4-related sialadenitis usually affects submandibular glands and is very rare in children. Here we report the case of IgG4-related sialadenitis in a six-year-old patient previously diagnosed as juvenile recurrent parotitis. CASE PRESENTATION: A six-year-old patient was referred to our Centre for left parotid swelling of 4 × 3 cm, that was tender, soft in consistency, with overlying red and warm skin. His general condition was good but he was subfebrile; general examination revealed mild enlargement of left cervical lymph nodes. In the last 2 years he had had five episodes of parotitis, diagnosed by another pediatric Center as juvenile recurrent parotitis. On ultrasound examination the left parotid gland appeared enlarged, inhomogeneous, with a colliquative intraparotid lymph node and no evidence of sialolithiasis. Laboratory tests showed an increase of white blood cells and anti-VCA IgM and IgG positivity, with anti-EBNA e anti-EA I negativity. The patient was initially treated with oral antibiotics, but after 10 days the parotid became fluctuating, requiring surgical biopsy and drainage. Postoperative course was regular, with complete remission under oral antibiotic and steroid therapy. Microbiological tests, including cultures for aerobic and anaerobic bacteria, mycobacteria and Bartonella, were negative. Surprisingly, histology showed marked fibrosis and histiocytic and lymphoplasmacellular infiltrate with polyclonal plasma cells mostly expressing IgG4 immunoglobulins. Thus, the diagnosis of IgG4 related chronic sialadenitis in recurrent parotitis and recent EBV infection was made. CONCLUSIONS: IgG4-related sialadenitis is very unusual in children. Histology plays a key role in diagnosis, considering that up to 30% of patients have normal serum IgG4 levels, as shown in our case. The lack of previous histological data makes it impossible to attribute our patient's previous episodes of parotitis to IgG4-RD, though it is a very consistent possibility.

Congenital Hypopigmentary Disorders with Multiorgan Impairment: A Case Report and an Overview on Gray Hair Syndromes.

The term congenital hypopigmentary disorders refers to a wide group of heterogeneous hereditary diseases, clinically characterized by inborn pigmentary defects of the iris, hair, and/or skin. They include Gray Hair Syndromes (GHSs), a rare group of autosomal recessive genodermatosis hallmarked by inborn silvery gray hair. GHSs encompass Griscelli, Chediak⁻Higashi, Elejalde, and Cross syndromes, which are all characterized by a broad spectrum of severe multisystem disorders, including neurological, ocular, skeletal, and immune system impairment. In this manuscript, we describe in detail the clinical, trichoscopic, and genetic features of a rare case of Griscelli syndrome; moreover, we provide an overview of all the GHSs known to date. Our report highlights how an accurate clinical examination with noninvasive methods, like trichoscopy, may play a crucial rule in diagnosis of rare and potentially lethal genetic syndromes such as Griscelli syndrome, in which timely diagnosis and therapy may modify the clinical course, quality of life, and likelihood of survival.

Hematopoietic stem cell transplantation in Niemann-Pick disease type B monitored by chitotriosidase activity.

Here, we report a patient with Niemann-Pick disease type B, with early severe onset of disease and pulmonary involvement, treated with hematopoietic stem cell transplant (HSCT) from a bone marrow matched unrelated donor. We confirm that HSCT is feasible and potentially beneficial for patients with severe phenotype. Noteworthy, we discussed the potential usefulness of the activity of peripheral chitotriosidase for the longitudinal evaluation of HSCT success and effectiveness.

A retrospective study of paroxysmal nocturnal hemoglobinuria in pediatric and adolescent patients.

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare disease, especially in children, characterized by intravascular hemolysis, thrombotic events, serious infections and bone marrow failure. We describe 16 patients who were diagnosed with PNH in childhood or adolescence. The time interval between the onset of symptoms and the PNH diagnosis and its treatment were compared in patients with classic PNH versus PNH associated with bone marrow disorder (PNH/BMD). A greater delay in diagnosis was observed in classic PNH compared to PNH/BMD patients. The first group of patients had higher levels of LDH, total bilirubin and absolute reticulocyte count and a bigger PNH clone size compared to PNH/BMD patients; also thrombotic events were observed only in the classic form of PNH. Conversely, PNH/BMD patients showed lower median levels of platelets. Apart from standard supportive measures, four patients with classic PNH received eculizumab whereas four patients with PNH/BMD underwent hematopoietic stem cell transplantation. Our series confirm that the most frequent presentation of PNH in the pediatric-adolescent age is PNH/BMD. The delay between the onset of symptoms and PNH diagnosis is relevant principally in the classic form. Moreover, our study showed that any case of unexpected thrombosis represents a criterium to perform a PNH screening.

Diagnosis and management of acquired aplastic anemia in childhood. Guidelines from the Marrow Failure Study Group of the Pediatric Haemato-Oncology Italian Association (AIEOP).

Acquired aplastic anemia (AA) is a rare heterogeneous disease characterized by pancytopenia and hypoplastic bone marrow. The incidence is 2-3/million inhabitants/year, in Europe, but higher in East Asia. Survival in severe aplastic anemia (SAA) has markedly improved in the past 2 decades because of advances in hematopoietic stem cell transplantation, immunosuppressive and biologic drugs, and supportive care. In SAA hematopoietic stem cell transplant (HSCT) from a matched sibling donor (MSD) is the treatment of choice. If a MSD is not available, the options include immunosuppressive therapy (IST) or unrelated donor HSCT. The objective of this guideline is to provide healthcare professionals with clear guidance on the diagnosis and management of pediatric patients with AA. A preliminary, evidence-based document issued by a group of pediatric hematologists was discussed, modified and approved during a series of "Consensus Conferences" according to procedures previously validated by the AIEOP Board. The guidelines highlight the importance of referring pediatric patients with AA to pediatric centers with long experience in diagnosis, differential diagnosis, management, supportive care and follow-up of AA.

Impact of SARS-CoV-2 Pandemic and Lockdown on the HRSV Circulation: Experience of Three Spoke Hospitals in Northern Italy.

The SARS-CoV-2 Pandemic affected the global epidemiology of respiratory infections, including Human Respiratory Syncytial Virus (HRSV), thanks to state governments' implementation of mitigation strategies, like the promotion of face masks and lockdowns. However, after the Pandemic, the dramatic resurge of these diseases was reported worldwide. Our retrospective study, involving three Spoke Pediatric Departments, includes all the infants under one year of age hospitalized for HRSV bronchiolitis in a period before the Pandemic period (2017-2020), during the SARS-CoV-2 Pandemic (2020-2021), and after the Pandemic (2021-2023). The primary aim was to analyze the temporal trend of HRSV in these three periods. Then, the clinical and epidemiological characteristics were analyzed to highlight the clinical differences in the affected patients, in the severity of the infections, and in the short-term outcomes. Ultimately, we analyzed the HRSV prevalence in the global bronchiolitis hospitalization over the reported periods. Overall, we included 237 patients. Before the Pandemic, the peak was recorded in January and February, while after the Pandemic, the peak was in November and December. A higher prevalence of HRSV was demonstrated after the Pandemic compared to the period before the Pandemic; overall, no difference in severity was reported. In conclusion, an increase in HRSV cases after the Pandemic has been demonstrated with an anticipated peak, while no differences were recorded in severity.

Management of Acute Bronchiolitis in Spoke Hospitals in Northern Italy: Analysis and Outcome.

Bronchiolitis is an acute viral infection of the lower respiratory tract that affects infants and young children. Respiratory syncytial virus (RSV) is the most common causative agent; however, other viruses can be involved in this disease. We retrospectively reviewed the clinical features of infants aged less than 12 months hospitalized for acute bronchiolitis in our Pediatric Units of Chivasso, Cirié, and Ivrea in Piedmont, Northern Italy, over two consecutive bronchiolitis seasons (September 2021-March 2022 and September 2022-March 2023). Patient-, disease-, and treatment-related variables were analyzed. The probability of therapeutic success (discharge home) was 96% for all patients (93% for RSV vs. 98% for non-RSV patients, p > 0.05). Among 192 patients, 42 infants (22%) underwent high-flow oxygen support (HFNC), and only 8 (4%) needed to be transferred to our hub referral hospital. Factors associated with hub hospital transfer were the age under 1 month and the failure of HFNC. The wide and increasing use of HFNC in pediatric inpatients improved the management of bronchiolitis in Spoke hospitals, reducing transfer to a hub hospital provided with Intensive Care Units.

Secondary hemophagocytic lymphohistiocytosis in children (Review).

Hemophagocytic lymphohistiocytosis (HLH) is a rare, life-threatening condition characterized by hyperinflammation in an uncontrolled and ineffective immune response. Despite great improvement in diagnosis and treatment, it still represents a challenge in clinical management, with poor prognosis in the absence of an aggressive therapeutic approach. The present literature review focuses on secondary HLH at pediatric age, which represents a heterogeneous group in terms of etiology and therapeutic approach. It summarizes the most recent evidence on epidemiology, pathophysiology, diagnosis, treatment and prognosis, and provides a detailed description and comparison of the major subtypes of secondary HLH. Finally, it addresses the open questions with a focus on diagnosis and new treatment insights.

The Importance of RSV Epidemiological Surveillance: A Multicenter Observational Study of RSV Infection during the COVID-19 Pandemic.

The restrictive measures adopted worldwide against SARS-CoV-2 produced a drastic reduction in respiratory pathogens, including RSV, but a dramatic rebound was thereafter reported. In this multicenter retrospective observational study in 15 Pediatric Emergency Departments, all children <3 years old with RSV infection admitted between 1 September and 31 December 2021 were included and compared to those admitted in the same period of 2020 and 2019. The primary aim was to evaluate RSV epidemiology during and after the COVID-19 pandemic peak. The secondary aims were to evaluate the clinical features of children with RSV infection. Overall, 1015 children were enrolled: 100 in 2019, 3 in 2020 and 912 in 2021. In 2019, the peak was recorded in December, and in 2021, it was recorded in November. Comparing 2019 to 2021, in 2021 the median age was significantly higher and the age group 2-3 years was more affected. Admissions were significantly higher in 2021 than in 2020 and 2019, and the per-year hospitalization rate was lower in 2021 (84% vs. 93% in 2019), while the duration of admissions was similar. No difference was found in severity between 2019-2020-2021. In conclusion, after the COVID-19 pandemic, an increase in RSV cases in 2021 exceeding the median seasonal peak was detected, with the involvement of older children, while no difference was found in severity.

Transcriptional hallmarks of Noonan syndrome and Noonan-like syndrome with loose anagen hair.

Noonan syndrome (NS) is among the most common nonchromosomal disorders affecting development and growth. NS is genetically heterogeneous, being caused by germline mutations affecting various genes implicated in the RAS signaling network. This network transduces extracellular signals into intracellular biochemical and transcriptional responses controlling cell proliferation, differentiation, metabolism, and senescence. To explore the transcriptional consequences of NS-causing mutations, we performed global mRNA expression profiling on peripheral blood mononuclear cells obtained from 23 NS patients carrying heterozygous mutations in PTPN11 or SOS1. Gene expression profiling was also resolved in five subjects with Noonan-like syndrome with loose anagen hair (NS/LAH), a condition clinically related to NS and caused by an invariant mutation in SHOC2. Robust transcriptional signatures were found to specifically discriminate each of the three mutation groups from 21 age- and sex-matched controls. Despite the only partial overlap in terms of gene composition, the three signatures showed a notable concordance in terms of biological processes and regulatory circuits affected. These data establish expression profiling of peripheral blood mononuclear cells as a powerful tool to appreciate differential perturbations driven by germline mutations of transducers involved in RAS signaling and to dissect molecular mechanisms underlying NS and other RASopathies.

Possible association between Guillain-Barré syndrome and SARS-CoV-2 infection in children: A case report and literature review.

Neurological manifestations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection have been reported in adults and in children, varying from mild to more debilitant symptoms, including fatigue, headache and dizziness. A series of studies have revealed a possible association between Guillain-Barré syndrome (GBS), the most common cause of acute flaccid paralysis at all ages, and SARS-CoV-2 infection. Case reports of novel coronavirus disease 2019 (COVID-19)-associated GBS mainly include adult patients, while only a few pediatric cases have been reported. The present study describes a case of GBS in an Italian 9-year-old girl with previous SARS-CoV-2 infection as a possible trigger, and also conducts a literature review on pediatric COVID-19-associated GBS cases.

Enzymatic Spermine Metabolites Induce Apoptosis Associated with Increase of p53, caspase-3 and miR-34a in Both Neuroblastoma Cells, SJNKP and the N-Myc-Amplified Form IMR5.

Neuroblastoma (NB) is a common malignant solid tumor in children and accounts for 15% of childhood cancer mortality. Amplification of the N-Myc oncogene is a well-established poor prognostic marker in NB patients and strongly correlates with higher tumor aggression and resistance to treatment. New therapies for patients with N-Myc-amplified NB need to be developed. After treating NB cells with BSAO/SPM, the detection of apoptosis was determined after annexin V-FITC labeling and DNA staining with propidium iodide. The mitochondrial membrane potential activity was checked, labeling cells with the probe JC-1 dye. We analyzed, by real-time RT-PCR, the transcript of genes involved in the apoptotic process, to determine possible down- or upregulation of mRNAs after the treatment on SJNKP and the N-Myc-amplified IMR5 cell lines with BSAO/SPM. The experiments were carried out considering the proapoptotic genes Tp53 and caspase-3. After treatment with BSAO/SPM, both cell lines displayed increased mRNA levels for all these proapoptotic genes. Western blotting analysis with PARP and caspase-3 antibody support that BSAO/SPM treatment induces high levels of apoptosis in cells. The major conclusion is that BSAO/SPM treatment leads to antiproliferative and cytotoxic activity of both NB cell lines, associated with activation of apoptosis.

Pediatric admissions to emergency departments of North-Western Italy during COVID-19 pandemic: A retrospective observational study.

BACKGROUND: COVID-19 pandemic caused huge decrease of pediatric admissions to Emergency Department (ED), arising concerns about possible delays in diagnosis and treatment of severe disorders. METHODS: Impact of COVID-19 on Pediatric Emergency Room (ICOPER) was a retrospective multicentre observational study including 23 Italian EDs.All the children <18 years admitted, between March 9th and May 3rd 2020 stratified by age, priority code, cause of admission and outcome have been included and compared to those admitted in the same period of 2019.Our objectives were to assess the characteristics of pediatric admissions to EDs since COVID-19 outbreak until the end of lockdown, and to describe the features of critical children. FINDINGS: 16,426 children were admitted in 2020, compared to 55,643 in 2019 (-70·48%). Higher reduction was reported in hospitals without Pediatric Intensive Care Unit (PICU) (-73·38%) than in those with PICU (-64·08%) (P<0·0001). Admissions with low priority decreased more than critical ones (-82·77% vs. 44·17% respectively; P<0·0001). Reduction of discharged patients was observed both in hospitals with (-66·50%) and without PICU (-74·65%) (P<0·0001). No difference in the duration of symptoms before admission was reported between 2019 and 2020, with the majority of children accessing within 24 h (55·08% vs. 57·28% respectively; P = 0·2344). INTERPRETATION: Admissions with low priority decreased significantly more than those with high priority; we suppose that the fear of being infected in hospital maybe overcame the concerns of caregivers. Compared to 2019, no significant referral delay by caregivers was reported. Our data suggest the need of adaptation of EDs and primary care services to different needs of children during COVID-9 pandemic.

Refreezing of cord blood hematopoietic stem cells for allogenic transplantation: in vitro and in vivo validation of a clinical phase I/II protocol in European and Italian Good Manufacturing Practice conditions.

OBJECTIVE: Several requirements need to be fulfilled for clinical use of expanded hematopoietic stem cells (HSCs). Because most cord blood (CB) samples are frozen in single bags and only an aliquot ( approximately 25%) of the blood can be expanded, the thawing and refreezing of samples must be validated in the current European and Italian Good Manufacturing Practice (eIGMP) conditions. Here, we describe in vitro and in vivo validation of the phase I/II protocol for CD34+ expansion of thawed CB units according to the current Cell Therapy Products (CTPs) Guidelines. MATERIALS AND METHODS: CB units were thawed and 25% of the total volume was processed for CD34+ selection by CliniMACS. The 75% of the unit was immediately refrozen. CD34+ cells were expanded for 3 weeks with stem cell factor, Flt-3/Flk-2 ligand, thrombopoietin, and interleukin-6. RESULTS: In vitro results demonstrated that this culture system induces expansion of thawed CD34+ (median value = 8.3). In vivo data demonstrated that after culture, the final CTPs maintain their repopulating ability in nonobese diabetic severe combined immunodeficient (SCID) mice. Limiting dilution assays performed by injecting decreasing doses of expanded CD34+ cells revealed that the frequency of SCID repopulating cells after ex vivo expansion is 1:8,034. Analyses for sterility, viability, cell senescence, and cytogenetic assessment demonstrated that expansion procedures in eIGMP conditions are safe for clinical protocols. CONCLUSIONS: This offers promising new options for expansion of allogenic HSCs and also for autologous usage in transplantation and other cell therapy protocols.

Reduction of CFU-GM and circulating hematopoietic progenitors in a subgroup of children with chronic neutropenia associated with severe infections and delayed recovery.

Myelopoiesis was evaluated in 66 pediatric patients with chronic neutropenia who were positive for anti-neutrophil antibodies (median age at diagnosis: 11 months, median neutrophil count at diagnosis: 419/µl). Other causes of neutropenia were excluded. Bone marrow morphology, clonogenic tests and/or the peripheral blood CD 34+ cell count, and apoptotic rate were evaluated in 61 patients with neutropenia lasting > 12 months or severe infections. The peripheral blood CD 34+ cell count and apoptotic rate were evaluated in five patients with shorter neutropenia. The median follow-up time was 29 months (range 7-180 months). Forty-seven patients (71.2%) had a spontaneous recovery after 7-180 months (median 29 months). The group of patients younger than 24 months at diagnosis (n = 50) had a higher probability of recovery (40/50 vs. 7/16 χ2 p<0.01) with a shorter period of neutropenia (median 26 versus 47 months, Kaplan-Meier analysis p = 0.001). The colony-forming units-granulocyte-macrophage (CFU-GM) were significantly decreased in 26/35 patients (74%) evaluated for clonogenic tests. All patients with normal CFU-GM recovered (9/9 patients); whereas, neutropenia persisted in 12/26 patients with reduced CFU-GM (46%, Pearson χ2 p = 0.02). In 36/55 (65%) patients evaluated by flow cytometry we observed reduced circulating CD34+ cells compared with controls of the same age. An increase in the circulating CD34+ cell apoptotic rate was observed in 28/55 patients (51%). Infections requiring hospitalization were observed in 9/18 (50%; Pearson χ2, p = 0.03) patients with both decreased circulating CD34+ cells and increased CD34+ apoptotic rates. In the group aged < 24 months, we observed a significant correlation between the persistence of neutropenia and decreased circulating CD34+ cells (Pearson χ2 p = 0.008). In conclusion, reduced CFU-GM and circulating hematopoietic progenitors were observed in a subgroup of children with chronic neutropenia who were positive for anti-neutrophil antibodies and had a higher incidence of severe infections and delayed spontaneous remission.

In vitro antiproliferative and antimigratory activity of dasatinib in neuroblastoma and Ewing sarcoma cell lines.

Neuroblastoma (NB) and Ewing sarcoma (ES) are neuroectodermal tumors typical of pediatric age that, despite aggressive treatment, still present a poor prognosis when in advanced stages. Studies indicate that c-KIT and platelet-derived growth factor receptor (PDGFR) play a substantial role in the proliferation and survival of NB and ES cells. Dasatinib, an oral multi-targeted inhibitor of several kinases including BCR-ABL and SRC-family kinases, is also active against c-KIT and PDGFR. Here, we evaluated the effect of dasatinib on the NB cell lines SJ-N-KP, SK-N-BE, AF8 and IMR5, and on the ES lines PDE02, TC106 and 6647. Proliferation and viability assays showed that dasatinib exerts an antiproliferative activity with a peak effect occurring at 24 h. After a 24-h exposure to dasatinib at 100 nM, proliferation was inhibited by 29.4+/-5.7% in SJ-N-KP, 41.3+/-11.7% in IMR5, 35.3+/-7.6% in PDE02 and 14+/-10.6% in 6647. Dasatinib did not induce apoptosis in NB and ES cell lines. A possible antimigratory activity of dasatinib was evaluated by scratch test. Dasatinib at 100 nM inhibited the migration of NB and ES cell lines by a mean of 30.2 and 25.3%, respectively. This activity suggests a possible role of dasatinib in inhibiting metastasis and appears of particular interest, given the association between metastatic disease and poor prognosis in these tumors. In conclusion, the cytostatic and antimigratory activity of dasatinib in NB and ES cell lines and the lack of pro-apoptotic activity suggests a possible use for this compound in the treatment of these tumors as a combination with other cytotoxic therapy.

Inhibition of heat shock proteins (HSP) expression by quercetin and differential doxorubicin sensitization in neuroblastoma and Ewing's sarcoma cell lines.

Neuroblastoma (NB) and Ewing's sarcoma (ES) represent the most common extracranial solid tumors of childhood. Heat shock proteins (HSP) are elevated in cancer cells and their over-expression was correlated to drug-resistance. In this work we identified the HSP by a sensitive proteomic analysis of NB and ES cell lines, then, we studied the HSP response to doxorubicin. Some identified HSP were constitutively more expressed in NB than in ES cells. Doxorubicin-stimulated HSP response only in NB cells. Quercetin was found to inhibit HSP expression depleting heat shock factor 1 (HSF1) cellular stores. Quercetin caused a higher anti-proliferative effect in NB (IC(50): 6.9 +/- 5.8 mumol/L) than in ES cells (IC(50): 85.5 +/- 53.1 mumol/L). Moreover, quercetin caused a very pronounced doxorubicin sensitizing effect in NB cells (241 fold IC(50) decrease) and a moderate effect in ES cells. HSP involvement in NB cells sensitization was confirmed by the silencing of HSF1. Quercetin treatment and HSF1 silencing increased the pro-apoptotic effect of doxorubicin. In conclusion, the higher HSP levels, observed in NB cells, did not confer increased resistance to doxorubicin; on the contrary, HSP inhibition by quercetin or gene silencing caused higher sensitization to doxorubicin. These results may have a potential application in the treatment of NB.