Immune thrombocytopenia in infants: a retrospective study with comparison to toddlers.

Introduction: Immune thrombocytopenia (ITP) is the most common cause of acquired bleeding in childhood, but little is known about the clinical course and outcomes in infants with ITP. Methods: This is a retrospective study of all infants (1-12 months of age) and toddlers (13-47 months of age) diagnosed with ITP from a single centre during a 13-year period. The following data were compared between the two patients groups: demographics, severity of bleeding, platelet counts, duration of illness, development of chronic ITP, treatment and association with recent vaccination. Results: Twenty-two infants and 30 toddlers were diagnosed and followed up for ITP during the study period. Infants with ITP generally had minor or mild bleeding (19, 86.4%) and seldom required treatment (7, 31.8%), and their thrombocytopenia resolved at a mean of 1.90 months after diagnosis. Besides age, the sex ratio, severity of bleeding, platelet counts and proportion that required treatment were comparable between infants and toddlers. Fewer infants developed chronic ITP (1/22 vs. 9/30, P = 0.032), but more infants had a history of vaccination in the preceding 6 weeks prior to diagnosis of ITP (13/22 vs. 1/30, P < 0.001). Conclusion: ITP in infants is almost always a self-limiting and transient illness, and the majority of cases do not require treatment.

Treatment and outcomes of high-risk neuroblastoma in Southeast Asia: a single-institution experience and review of the literature.

Introduction: In Europe and North America, the majority of children with high-risk neuroblastoma survive the disease. Elsewhere, the treatment outcomes are poor. Methods: A retrospective review of children treated for high-risk neuroblastoma in a single institution in Singapore from 2007 to 2019 was carried out. Treatment consisted of intensive chemotherapy, surgery aimed at gross total resection of residual disease after chemotherapy, consolidation with high-dose therapy followed by autologous stem cell rescue, and radiotherapy to the primary and metastatic sites followed by maintenance treatment with either cis-retinoic acid or anti-disialoganglioside monoclonal antibody therapy. Survival data were examined on certain clinical and laboratory factors. Results: There were 57 children (32 male) treated for high-risk neuroblastoma. Their mean age was 3.9 (range 0.7-14.9) years. The median follow-up time was 5.5 (range 1.8-13.0) years for the surviving patients. There were 31 survivors, with 27 patients surviving in first remission, and the five-year overall survival and event-free survival rates were 52.5% and 47.4%, respectively. On log-rank testing, only the group of 17 patients who were exclusively treated at our centre had a survival advantage. Their five-year overall survival rate compared to patients whose initial chemotherapy was done elsewhere was 81.6% versus 41.1% (P = 0.011), and that of event-free survival was 69.7% versus 36.1% (P = 0.032). Published treatment results were obtained from four countries in Southeast Asia with five-year overall survival rates from 13.5% to 28.2%. Conclusion: Intensified medical and surgical treatment for high-risk neuroblastoma proved to be effective, with superior survival rates compared to previous data from Southeast Asia.

Targeted Gene Sanger Sequencing Should Remain the First-Tier Genetic Test for Children Suspected to Have the Five Common X-Linked Inborn Errors of Immunity.

To address inborn errors of immunity (IEI) which were underdiagnosed in resource-limited regions, our centre developed and offered free genetic testing for the most common IEI by Sanger sequencing (SS) since 2001. With the establishment of The Asian Primary Immunodeficiency (APID) Network in 2009, the awareness and definitive diagnosis of IEI were further improved with collaboration among centres caring for IEI patients from East and Southeast Asia. We also started to use whole exome sequencing (WES) for undiagnosed cases and further extended our collaboration with centres from South Asia and Africa. With the increased use of Next Generation Sequencing (NGS), we have shifted our diagnostic practice from SS to WES. However, SS was still one of the key diagnostic tools for IEI for the past two decades. Our centre has performed 2,024 IEI SS genetic tests, with in-house protocol designed specifically for 84 genes, in 1,376 patients with 744 identified to have disease-causing mutations (54.1%). The high diagnostic rate after just one round of targeted gene SS for each of the 5 common IEI (X-linked agammaglobulinemia (XLA) 77.4%, Wiskott-Aldrich syndrome (WAS) 69.2%, X-linked chronic granulomatous disease (XCGD) 59.5%, X-linked severe combined immunodeficiency (XSCID) 51.1%, and X-linked hyper-IgM syndrome (HIGM1) 58.1%) demonstrated targeted gene SS should remain the first-tier genetic test for the 5 common X-linked IEI.

A multicenter report on the safety and efficacy of plerixafor based stem cell mobilization in children with malignant disorders.

BACKGROUND: Pleraxifor for peripheral blood stem cell (PBSC) mobilization in children with malignancies is often given following failure of standard mobilization (SM) rather than as a primary mobilizing agent. STUDY DESIGN AND METHODS: In this retrospective multicenter study, we report the safety of plerixafor-based PBSC mobilization in children with malignancies and compare outcomes between patients who received plerixafor upfront with SM (Group A) with those who received plerixafor following failure of SM (Group B). In the latter pleraxifor was given either following a low peripheral blood (PB) CD34 (<20 cells/cu.mm) (Group B1) or as a second collection process due to an unsuccessful yield (CD34 + < 2 × 106 /kg) (Group B2) following failed SM and first apheresis attempts. RESULTS: The study cohort (n = 47) with a median age of 8 (range 0.6-21) year, comprised 19 (40%) Group A and 28 (60%) Group B patients (B1 = 12 and B2 = 16). Pleraxifor mobilization was successful in 87.2% of patients, similar between Groups A and B (84.2% vs 89.2%) and resulted in a median 4-fold increase in PB CD34. Median number of apheresis attempts was 2 in Groups A and B1 but 4 in Group B2. In Group B2, median total CD34+ yield post-plerixafor was 9-fold higher than after SM (P = .0013). Mild to moderate transient adverse events affected 8.5% of patients. Among patients who proceeded to autologous transplant (n = 39), all but one engrafted. CONCLUSION: Plerixafor-based PBSC collection was safe and effective in our cohort and supports consideration as a primary mobilizing agent in children with malignancies.

Burkitt Lymphoma Presenting as Acute Pancreatitis: Report of 3 Cases and Review of the Literature.

Acute pancreatitis is a rare presentation in Burkitt lymphoma (BL) and may lead to delayed medical or unnecessary surgical treatment. Three cases of BL presenting as acute pancreatitis in the authors' institutions were described. Similar cases reported in the medical literature were collected and described along with the authors' cases. There were 12 cases described in the medical literature and hence a total of 15 cases of BL presenting as acute pancreatitis. Fourteen cases were the first diagnosis, and the other presented at lymphoma relapse. Twelve cases occurred in children under 15 years. Twelve patients had extrapancreatic disease. Three children were treated with surgery before diagnosis. Two patients died. Six of the remaining had adequate follow-up and were surviving in remission 8 months to 16 years after diagnosis. Lymphoma should be included in the differential diagnosis of acute pancreatitis in children. Acute pancreatitis in combination with malignant infiltration on imaging is highly suggestive of BL, especially in the jaundiced child.

Treatment of hepatic veno-occlusive disease in children with N-acetylcysteine.

In our institution, hepatic veno-occlusive disease/sinusoidal obstruction syndrome (VOD/SOS) has been treated with N-acetylcysteine (NAC) since 2008-a loading dose of 150 mg/kg, followed by 12 doses of 70 mg/kg 6 hourly. Nine children were diagnosed with hepatic VOD/SOS. Hepatic VOD/SOS occurred in seven children after stem cell transplantation and two were receiving chemotherapy for Wilms tumor. Their clinical severity was classified as moderate in two and severe in seven by the European Society for Blood and Marrow Transplantation criteria. All children recovered and were discharged from 4 to 16 days after diagnosis. No side effects were observed. Intravenous NAC is an effective treatment for hepatic VOD/SOS.

Macropolycyte in Pediatrics.

Macropolycytes are tetraploid neutrophils produced during accelerated myelopoiesis. They have been reported in adults with pernicious anemia, sepsis, and after cytotoxic chemotherapy. Two pediatric cases are reported, one after granulocyte colony-stimulating factor treatment and the other following Kawasaki disease, respectively.

Idiopathic Purpura With Gray Platelets: an Acquired Form of Gray Platelet Syndrome.

An acquired, transient bleeding disorder that predominantly affects children in Southeast Asia has been reported for the last 4 decades. The condition has been named idiopathic purpura with gray platelets (IPGP) or acquired platelet dysfunction with eosinophilia. In a retrospective review from a private pediatric clinic over an 8-year period, 10 consecutive children were diagnosed as IPGP with a mean age of 8.4 (3.7 to 16.2) years. Eosinophilia (>0.5×10/L) was absent in 1, while gray platelets were consistently found in all cases with a mean proportion of 64.5% (40% to 80%). Platelet aggregation tests were performed in 9 patients with abnormal responses consistent with platelet storage pool defect. All children recovered completely and spontaneously from 1 to 4 months after diagnosis without specific therapy. In an otherwise well child who presents abruptly with easy bruising and a platelet count >100×10/L, IPGP can be readily recognized as an acquired form of gray platelet syndrome. Eosinophilia is common but not mandatory for diagnosis.