A Descriptive 5-Year Analysis of the Demographics and Therapies for Patients With Immune Thrombotic Thrombocytopenic Purpura in the USA: A Multicenter Study of 390 Disease Episodes From 2017 to 2021

Immune thrombotic thrombocytopenic purpura (iTTP) is characterized by microangiopathic hemolytic anemia, thrombocytopenia, and microvascular occlusion secondary to acquired ADAMTS13 deficiency. Contemporary data regarding iTTP treatment practices in the US, including the use of caplacizumab, are lacking. We aimed to characterize the demographics and therapies, including medications and apheresis practices, in patients with iTTP in the US. We retrospectively analyzed iTTP cases at 15 sites in the US that provide comprehensive care for patients with iTTP. The time-period assessed was from January 1, 2017 to December 31, 2021. Our primary objective was to analyze data by iTTP episode, inclusive of initial episodes and relapses. A total of 390 iTTP episodes were reported for 280 unique individuals (187 females, 93 males). Thirty-day mortality was 3.7% (14/374), and 6-month mortality was 7.4% (27/367). TPE details were reported for 343 episodes, among which 261 underwent at least one procedure (median 6, IQR 3-11). Among the 261 episodes with at least one therapeutic plasma exchange (TPE) performed, 82.0% (214/261) used only plasma. Caplacizumab was used either alone or in combination with other agents in 43 (11.0%) episodes. Management strategies for iTTP remain varied across centers in the US, with a variety of combinations for TPE replacement fluids and therapeutic agents, as well as limited use of caplacizumab. Further research and standardization of treatment regimens may further reduce mortality in this condition.

Pediatric Mesenchymal Tumors

Vascular, fibrous/myofibroblastic, and myogenic tumors account for the majority of mesenchymal tumors in children. These tumors often show significant overlap in morphology and immunophenotype posing diagnostic difficulties and, thus, their classification remains challenging. Recent advances in immunohistochemistry have proved helpful in identifying a specific line of differentiation in some tumors, but other tumors remain difficult to classify. Molecular investigations have provided an existing tool to better understand the pathogenesis of some of these tumors and, in some cases like the EWING family of tumors, expanded the classification resulting in the emergence of previously unknown tumors. Some of these tumors are currently diagnosed according to their underlying molecular abnormality, such as CIC -rearranged sarcoma, BCOR -rearranged sarcoma, etc. This review focuses on the common mesenchymal neoplasms of the pediatric population with emphasis on the salient histologic features, immunoprofile, and molecular characteristics. For practical purposes, the latter are summarized in Supplemental Table 1, Supplemental Digital Content 1, http://links.lww.com/PAP/A46 .

Utility of Repeated NGS Testing in Myeloid Diagnostic Work Up

Introduction/Objective

NGS is an integral component of diagnostic work-up of myeloid neoplasms, commonly applied at initial diagnosis and for assessment of treatment response. It is less clear how NGS should be repeated at disease follow-up when initial result is negative. In order to assess the utility of repeated NGS testing, we retrospectively analyzed results in patients with multiple tests.

Methods/Case Report

Myeloid NGS results were collected between 10/2017 and 4/2022 at University of Miami. The results were grouped by patients and arranged by collection date and finding of mutations. First, we identified patients with negative result or a single mutation of common CHIP gene TET2, DNMT3A, or ASXL1 (DAT) in the first available NGS test. Then we divided these patients into negative follow-up group, if all NGS results were the same as the initial test, and positive follow-up group, if any new mutations were detected. The NGS findings were correlated with clinical history and pathology diagnosis.

Results (if a Case Study enter NA)

Results from 876 patients were analyzed. A total of 362 patients underwent multiple NGS tests; among them, 84 were negative and 14 had a single DAT mutation in the first NGS test. Among the 98 patients, 21 (21.4%) were in the positive follow-up group, with median time-to-positive at 132 days; the other were in the negative follow-up group with median follow-up time at 258 days. Analysis of the patient history showed the positive follow-up group consists 16 patients who were in remission of high-grade myeloid neoplasm at the time of initial testing and relapsed at the time of detection of mutations, 4 patients who acquired alteration of uncertain significance after hematopoietic stem cell transplant, and 1 patient who acquired KRAS mutation corresponding to MDS developed 846 days after the initial testing.

Conclusion

Positive conversion in repeated NGS testing are mostly associated with relapsed myeloid neoplasm after chemotherapy.

Unveiling renal pathology's potential: exploring a rare subtype of amyloid - apolipoprotein CII amyloidosis in the youngest patient: a case report and literature review

In this clinical case report, we present a rare subtype of amyloidosis, apolipoprotein CII (apo CII), which was diagnosed through a renal biopsy and subsequently confirmed by identifying the p.K41T mutation via germline DNA sequencing. Upon reviewing the literature, five patients exhibiting identical mutation were identified via renal biopsy, while an additional patient was diagnosed through biopsies of the fat pad and bone marrow. Notably, our patient is the youngest recorded case. We pioneered the application of immunofluorescence and immunogold electron microscopy techniques for apo CII evaluation. Our report provides a detailed description of this case, supplemented by an extensive review encompassing apo CII, documented instances of apo CII amyloidosis with renal or systemic involvement, and potential underlying mechanisms.