Introduction: Thrombocytopenia is a common clinical problem in cancer patients undergoing high-dose chemotherapy and autologous hematopoietic stem cell transplantation (HSCT). It can occur as prolonged isolated thrombocytopenia (PIT) or secondary failure of platelet recovery (SFPR) and may cause potentially fatal bleeding. However, data on the treatment of post-transplant thrombocytopenia is still lacking. Methods: We reported our practices involving 15 pediatric patients who received eltrombopag (ELT) treatment for PIT and SFPR after autologous HSCT. Results: The overall response was 78.5% (11/14), with 1 patient excluded due to noncompliance. The 12 surviving patients' median follow up was 699 days (range: 167 to 2250 d). Conclusions: Our study indicates the efficacy and safety of ELT for treating PIT and SFPR after autologous HSCT in pediatric patients. However, more studies are needed to confirm these findings in children.

Objective: In this study, we sought to describe the clinical, laboratory, and genetic character- istics of patients diagnosed with primary hemophagocytic lymphohistiocytosis. Thus, we aimed to evaluate the early diagnosis and appropriate treatment options for pediatric hemophago- cytic lymphohistiocytosis patients. Materials and Methods: Medical records of 9 patients diagnosed with primary hemophago- cytic lymphohistiocytosis between November 2013 and December 2019 were analyzed retro- spectively. Clinical, genetic, and laboratory characteristics, family histories, initial complaints, physical examination findings, age at diagnosis, treatment choices, and clinical follow-up of all patients were investigated. Results: The mean age at diagnosis was 11 months (range: 1.5 months to 17 years). Genetic analysis was performed in all patients, and a disease-related mutation was detected in 8 (89%) of them. Among clinical features, 6 (66%) patients had fever, 5 (56%) had splenomegaly, 4 (44%) had lymphadenopathy, 4 (44%) had skin rash, and 4 (44%) had neurological findings. Hemophagocytosis was observed in the bone marrow samples of 6 (66%) patients. Disease remission was achieved in 7 (78%) patients. Hematopoietic stem cell transplantation was per- formed in 7 (78%) patients. Conclusion: Hemophagocytic lymphohistiocytosis may present with different clinical symptoms that can cause a significant diagnostic delay. The only curative treatment option in primary hemophagocytic lymphohistiocytosis patients is hematopoietic stem cell transplantation. The chemotherapy should be started as early as possible, in order to achieve a disease remission. Patients should be referred to the appropriate bone marrow transplant center for hematopoi- etic stem cell transplantation as soon as they reach the disease remission. Cite this article as: Nepesov S, Yaman Y, Elli M, et al. Clinical, genetic, and outcome characteristics of pediatric patients with primary hemophagocytic lymphohistiocytosis. Turk Arch Pediatr. 2022;57(4):398-405.

Background: Hodgkin lymphoma (HL) is predominantly a nodal disease with extranodal presentation being uncommon. Presentation with neurological symptoms is not uncommon in adult patients with HL. Subdiaphragmatic involvements are less common especially in childhood. In the literature, there has been no case which presented with both spinal cord compression and bilateral hydronephrosis in pediatric patients with HL. Observation: We report a 9-year-old boy diagnosed with HL who presented with bilateral hydronephrosis and epidural involvement. Conclusion: Differential diagnosis of abdominal mass in patients presenting with spinal cord compression and/or hydronephrosis should include HL. Retrograde J ureteral stenting is the treatment of choice for malignant ureteral obstruction.