The frequency and clinical outcome of mono-hit and multi-hit TP53 aberrations in newly diagnosed multiple myeloma.

We investigated the frequency and outcome of mono-hit and multi-hit TP53 aberrations [biallelic or ≥1 TP53 mutations (TP53mut) or TP53mut with variant allele frequency (VAF) ≥55%] in an Indian cohort of newly diagnosed multiple myeloma (NDMM) patients. We employed fluorescence insitu hybridisation (FISH; n=457) and targeted next-generation sequencing (NGS; n=244) on plasma cell-enriched samples. We also studied the impact of TP53mut in cases with and without TP53 deletions (TP53del). In our cohort with a median age of 60 years, TP53del and TP53mut were seen in 12.9% (n=59/457; 14-95% cells) and 10.2% (n=25/244; 30 variants; VAF 3.4-98.2%; median 38.2%) respectively. Mono-hit and multi-hit-TP53 aberrations were observed in 10.2% and 7.8%, respectively. Compared to TP53-wild-type (TP53wt), mono-hit and multi-hit TP53 aberrations were associated with significantly poorer progression-free survival (PFS) (22.6 vs 12.1 vs 9.5 months; p=0.004) and overall survival (OS) [not reached (NR) vs 13.1 vs 15.6 months respectively; p=0.024]. However, multi-hit TP53 did not significantly differ in OS/PFS compared to mono-hit cases. Compared to TP53wt, PFS and OS were significantly poorer in patients with TP53mut only (9.5 vs 22.6 months and 12.1 months vs NR, respectively; p=0.020/0.004). TP53mut retained its significance even in the presence of any Revised International Staging System (HR 2.1; 95% CI 1.1-3.8; p=0.015) for OS. The detection of additional cases with TP53 aberrations, as well as poor survival associated with the presence of mutation alone, supports TP53mut testing in NDMM at least in patients without TP53del and other high-risk cytogenetic abnormalities.

Case Report: A Case of Complicated Typhoid Fever with Rhabdomyolysis and Hemophagocytic Lymphohistiocytosis.

Typhoid fever can have diverse extra-intestinal complications including encephalitis, Guillain-Barré syndrome, endocarditis, myocarditis, osteomyelitis, renal abscess, and splenic abscesses. Secondary hemophagocytic lymphohistiocytosis with rhabdomyolysis is a rare complication of typhoid fever. Here, we present the case of an adolescent with typhoid fever complicated by rhabdomyolysis and hemophagocytic lymphohistiocytosis.

A surrogate molecular approach for the detection of Philadelphia chromosome-like B-acute lymphoblastic leukemia.

BACKGROUND: Philadelphia chromosome (Ph)-like B-acute lymphoblastic leukemia (B-ALL) is a clinically significant, high-risk genetic subtype of B-ALL cases. There are few data on the incidence, characterization, and treatment outcomes of Ph-like ALL cases from low- and middle-income countries. There is a pressing need to establish a well-organized/cost-effective approach for identifying Ph-like ALL instances. METHODS: Multiplex reverse transcriptase polymerase chain reaction, nCounter NanoString, and fluorescence in situ hybridization were used to detect and characterize Ph-like ALL cases among recurrent genetic abnormalities (RGA)neg B-ALL cases. At the end of induction therapy, flow cytometry-minimal residual disease (MRD) assay was used to quantify MRD positivity in Ph-like ALL cases. RESULTS: Of 130 newly diagnosed B-ALL cases, 25% (BCR::ABL1), 4% (ETV6::RUNX1), 5% (TCF3::PBX1), 2% (KM2TA::AFF1), and 65% RGAneg B-ALL cases were revealed by multiplex reverse transcriptase polymerase chain reaction. Among RGAneg B-ALL cases, 24% Ph-like ALL cases using nCounter NanoString were identified, with 48% CRLF2high cases with 45% CRLF2::P2RY8 and 18% CRLF2::IGH rearrangements(∼r) revealed by fluorescence in situ hybridization. In 52% of CRLF2low cases, 17% ABL1 and JAK2∼r 8% EPOR::IGH & PDGRFB∼r were identified. Ph-like ALL cases had higher total leukocyte count (p < .05), male preponderance (p < .05), and high MRD-positivity/induction failure compared with RGAneg B-ALL cases. Furthermore, in Ph-like ALL cases, 11 significant genes using quantitative polymerase chain reaction were identified and validated. CRLF2, IGJ, CEACAM6, MUC4, SPATS2L and NRXN3 genes were overexpressed and show statistical significance (p < .05) in Ph-like ALL cases. CONCLUSIONS: This study showed the high incidence of Ph-like ALL cases with kinase activating alterations and treatment outcomes from low- and middle-income region. Furthermore, a surrogate cost-effective multiplex panel of 11 overexpressed genes for the prompt detection of Ph-like ALL cases is proposed. PLAIN LANGUAGE SUMMARY: Identification of recurrent gene abnormalities (RGA)neg B-acute lymphoblastic leukemia (B-ALL) cases using multiplex-reverse transcriptase polymerase chain reaction. Identification and characterization of Philadelphia (Ph)-like ALL cases using nCounter NanoString gene expression profiling and fluorescence in situ hybridization. Furthermore, Ph-like ALL cases were characterized according to CRLF2 expression and kinase-activating genomic alterations. Minimal residual disease of Ph-like ALL cases were quantified using flow cytometry-minimal residual disease assay. A surrogate molecular approach was established to detect Ph-like ALL cases from low- and middle-income countries.

FLAER as a standalone reagent for paroxysmal nocturnal hemoglobinuria: Do we need to reconsider the guidelines for testing?

INTRODUCTION: Flow cytometry-based paroxysmal nocturnal hemoglobinuria (PNH) testing involves utilization of monoclonal antibodies against GPI-linked proteins and FLAER. The ability of FLAER to bind to a wide variety of GPI-linked structures and to be utilized across different leukocyte subsets is remarkable. We hypothesize that FLAER as a standalone reagent may be equally effective for detecting PNH clones. The present study intends to compare the results of a FLAER alone-based strategy to the recommended FLAER+GPI-linked protein-based approach for applicability in clinical settings. METHODS: EDTA-anticoagulated blood samples from patients for PNH workup were tested for PNH by multiparametric flow cytometry. A conventional panel comprising gating markers (CD45 for WBC, CD15 for granulocytes, and CD64 for monocytes) and a combination of FLAER and GPI-linked markers, such as CD24 and CD14, henceforth referred to as the "routine panel," was employed. Second, a "FLAER-only panel" comprising the gating markers and FLAER alone (excluding the GPI-linked markers CD24 and CD14) was set up. The samples were processed using the lyse-wash-stain-wash technique, and events were acquired on BC Navios Ex flow cytometer (Beckman Coulter, Inc., USA) and analyzed on Kaluza Software 2.1. The presence of a PNH clone was reported at a value of ≥0.01%. RESULTS: A total of 209 patients were tested. Both panels found a PNH clone in 20.1% of patients (n = 42/209) with a 100% concordance rate. The PNH clone range for granulocytes was 0.01%-89.68%, and for monocyte was 0.04%-96.09% in the routine panel. The range in the FLAER-only panel for granulocytes was 0.01%-89.61%, and for monocytes, it was 0.01%-96.05%. Pearson correlation statistics revealed a significant correlation between the size of the PNH clone of granulocytes and monocytes among the two panels tested (granulocytes r = 0.9999, p < 0.0001, 95% CI = 0.9999 to 1.000; monocytes r = 0.9974, p < 0.0001, 95% CI = 0.9966-0.9980). CONCLUSION: Based on our results, FLAER as a standalone marker is specific and sensitive for identifying PNH clones in granulocytes and monocytes, even for high-sensitivity PNH assay. The proposed "FLAER-only panel" panel is efficient and cost-effective for highly sensitive PNH testing in two different cell lineages, especially in resource-limited clinical settings.

Detection of circulating normal and tumor plasma cells in newly diagnosed patients of multiple myeloma and their associations with clinical and laboratory parameters.

INTRODUCTION: Circulating plasma cells (CPCs) are frequently noted in variable frequencies in the entire spectrum of plasma cells neoplasms. With advent of high sensitivity multi-parametric flow cytometry, it is not only possible to detect CPCs present in very low numbers, but also to categorise them into circulating tumor plasma cells (CTPCs) and circulating normal plasma cells (CNPCs), based on their marker-profile. This study used multi-colour flow cytometry to evaluate the load of both CTPCs & CNPCs at the time of diagnosis and at six months' time-point of therapy, and evaluated associations of both with clinical and laboratory parameters. METHODS: Twenty one newly diagnosed MM patients were enrolled. Six to nine millilitres of EDTA-anticoagulated peripheral blood sample was used for flow cytometry. A ten colour antibody panel was used for analysis of CPCs, which were categorised further into CTPCs and CNPCs. Approximately 4.8 million events were acquired for the analysis. The percentage &absolute numbers of CTPCs and CNPCs were noted and the proportion of CTPCs out of all CPCs (CTPCs + CNPCs) were also calculated for evaluating their statistical associations. RESULTS: All 21 patients of newly diagnosed MM showed presence of CPCs (CTPCs and/or CNPCs) at the time of diagnosis. The CTPCs were detected in 76 % of the study population. The median percentage and absolute counts of CTPCs were 0.52 % and 54.9 cells /µL, respectively. CNPCs were found in 95 % and the median percentage and absolute counts of CNPCs were 0.025 % and 2.66 cells/µL. After six months of therapy, CPCs (CTPCs and/or CNPCs) were found in all nine patients evaluated for this assay. CTPCs were found 33 %, with a median of 0.075 % and CNPCs were found in 89 % with a median of 0.01 %. Our study showed that the load of CTPCs was found to be higher in patients with presence of lytic bone lesions, plasmacytoma, presence of PCs on peripheral blood film by light microscopy, presence of Chr 1p32 deletion, expression of CD56 and CD81 on CTPCs, and in patients with absence of very good partial response (VGPR). Conversely, the load of CTPCs was significantly lower in patients with concomitant amyloidosis. Also, percentage of bone marrow plasma cells exhibited a significant positive correlation with the absolute count of CTPCs. We observed that the mean percentage of CNPCs was significantly higher in female patients. The load of CNPCs was lower in patients with thrombocytopenia and with hypoalbuminemia. CONCLUSION: Increased burden of CTPCs was associated with presence of lytic lesions, plasmacytomas, Chr 1p32 deletion, expression of CD56 and CD81 on tumor cells and with failure to achieve very good partial response. The CNPCs were lower in patients with thrombocytopenia and with hypoalbuminemia. To best ot our knowledge, this is the first study from India on the relevance of circulating tumor plasma cells and the first study in the world to analyse the associations of circulating normal plasma cells in newly diagnosed patients of multiple myeloma. The study also highlights the utility of multi-parametric flow cytometry in identification and enumeration of circulating plasma cells. MICRO ABSTRACT: Circulating plasma cells indicates poorer outcomes in patients of multiple myeloma. Twenty one newly diagnosed multiple myeloma patients were evaluated by flow cytometry to enumerate and characterise circulating tumor plasma cells (CTPCs) and circulating normal plasma cells (CNPCs). Higher load of CTPCs correlated with known poor prognostic markers and poor response to therapy.

Hemophagocytic Lymphohistiocytosis due to Disseminated Histoplasmosis in a Patient with HIV Infection.

Hemophagocytic lymphohistiocytosis is usually considered a rapidly progressive fatal illness with poor outcomes. It is of two types: primary or familial and secondary. In patients with HIV, opportunistic infections are the secondary triggers of HLH. First line of management of infection associated HLH is treatment of the underlying infection. Here, we present a case of HLH in HIV infection due to disseminated histoplasmosis managed with liposomal amphotericin B, who required immunosuppressive therapy with intravenous immunoglobulin and dexamethasone due to nonresponse to primary therapy.

Navigating through the diagnostic minefield of clear cell sarcoma of soft tissue: Lessons from a challenging case with literature review.

Clear cell sarcoma of soft tissue (CCSST) is a rare soft tissue sarcoma occurring in young adults with a predilection for deep soft tissues of the distal extremities. Its overlapping morphology and immunohistochemical profile pose a diagnostic challenge. Herein, we present a rare case of CCSST with a unique immunohistochemical profile arising in an uncommon location. A 36-year-old male presented with a progressively increasing painful swelling in the left supraclavicular region for the last 2 months. Positron emission tomography showed FDG-avid lesions in the left supraclavicular and scapular regions. Fine needle aspiration cytology (FNAC) followed by core needle biopsy was performed. The cytology smears showed predominantly discohesive sheets of polygonal tumor cells with prominent macronucleoli in a vacuolated background. On immunocytochemistry, tumor cells showed positivity for vimentin, HMB45, and S100, confirming the diagnosis of CCSST. Histopathological examination showed sheets of similar tumor cells that were positive for vimentin, HMB45, melan A, CD38, and CD138, representing a potential diagnostic pitfall in the index case. The index report, besides highlighting the characteristic pathologic features of CCSST and its mimics, is unique due to the diffuse positivity of the tumor cells for CD38 and CD138. It is imperative to be aware of this diagnostic pitfall as it may muddle the diagnosis of CCSST.

Characteristics and outcome of infectious complications after autologous hematopoietic cell transplantation in multiple myeloma patients.

BACKGROUND: Infections are a significant cause of morbidity and mortality after autologous hematopoietic cell transplantation (AHCT) in multiple myeloma (MM) patients. There has been a rapid advancement and evolution in MM treatment landscape in the last decade. There is limited information on post-AHCT infectious complications among MM patients with or without levofloxacin prophylaxis from developing countries. MATERIALS AND METHODS: We performed a retrospective study to explore the incidence, pattern, and clinical outcome of infections following AHCT in MM patients from 2010 to 2019 at our center. Patient-specific, disease-specific, and transplant-specific details were retrieved from the case files. The characteristics of infectious complications (site, intensity, organism, treatment, and outcomes) were analyzed. All patients who underwent transplantation from 2010 to 2016 received levofloxacin antibiotic prophylaxis. Common terminology criteria for adverse events (CTCAE) criteria (v5.0) were used for the grading of infections and regimen-related toxicity. International Myeloma Working Group updated criteria were used for the assessment of disease response before transplant and at day +100. RESULTS: Ninety-five consecutive patients with newly diagnosed multiple myeloma (NDMM) (n = 85), RRMM (n = 7), plasma cell leukemia (n = 2), and Polyneuropathy, Orgaomegaly, Endocrinopathy, Monoclonal gammopathy, skin abnormalities (POEMS) syndrome (n = 1) underwent AHCT during the study period. Their median age was 55 years (range 33-68); 55.8% were males. Immunoglobulin IgG kappa was the most common monoclonal protein (32.6%), International Staging System stage III disease was present in 45.3%, and 84.2% of patients achieved more than very good partial response before AHCT. The median time from diagnosis to AHCT was 10 months (range 4-144). Eighty-nine patients (93.7%) developed fever after AHCT. Fever of unknown focus, microbiologically confirmed infections, and clinically suspected infections were found in 50.5%, 37.9%, and 5.3% of patients, respectively. Clostridiodes difficile-associated diarrhea was observed in eight patients (8.4%). Neutrophil and platelet engraftment occurred after a median of 11 days (range 9-14) and 12 days (range 9-23), respectively. The median duration of hospital stay was 16 days (range 9-29). Only two patients (2.1%) required readmission for infections within 100 days of AHCT. Transplant-related mortality (TRM) in the study population was 4.2% (n = 4). The levofloxacin prophylaxis group (n = 32, 33.7%) had earlier neutrophil engraftment (day +10 vs. day +11) and platelet engraftment (day +11 vs. day +12), but time to fever onset, duration of fever, hospital stay, TRM, and day +100 readmission rates were not significantly different from those of patients without levofloxacin prophylaxis. There was no significant difference in the spectrum of infections between patients with and without levofloxacin prophylaxis. The overall survival and progression-free survival of the study population at 5 years were 72.7% and 64.8%, respectively. CONCLUSION: This study shows that the incidence of infections and TRM are higher in MM patients from lower-middle income countries after AHCT than in those from developed countries. The majority of such patients lack clinical localization and microbiological proof of infection. There was no significant difference in the spectrum of infections and their outcomes in patients with and without levofloxacin prophylaxis.

Identification and validation of the optimal reference genes for standardizing the gene expression profiling diagnostic panel of Ph-like B-lineage acute lymphoblastic leukemia.

Gene expression profiling is the criterion standard for recognizing Ph-like ALL signatures among B-ALLs. The prerequisite of GEP is the accurate normalization of target genes with stable expression of housekeeping genes in a quantitative PCR. HKGs exhibit differential expression in the different experimental conditions and affect the target genes' expression, leading to imprecise qPCR results. The selection of stable HKGs is crucial in GEP experiments, especially in identifying high-risk Ph-like ALL cases. We have evaluated the expression stability of nine HKGs (GAPDH, ACTB, GUSB, RNA18S, EEF2, PGK1, B2M, TBP and ABL1) in identified Ph-like ALLs and Ph-negative (n = 23 each) using six algorithms, 4 traditional softwares; geNorm, BestKeeper, NormFinder, Delta Cq value method, and two algorithms, RefFinderTM and ComprFinder. Further, we have validated the expression of 8 overexpressed normalized genes in Ph-like ALL cases (JCHAIN, CA6, MUC4, SPATS2L, BMPR1B, CRLF2, ADGRF1 and NRXN3). GeNorm, BestKeeper, NormFinder, Delta Cq value method, RefFinderTM and ComprFinder algorithm analysis revealed that EEF2, GAPDH, and PGK1 form the best representative HKGs in Ph-like ALL cases, while RNA18s, ß-actin, and ABL1 in Ph-negative ALLs. Lastly, we performed a correlation analysis and found that the combination of EEF2, GAPDH, and PGK1 represents the best combination with a very high correlation in Ph-like ALL cases. This is the first report that shows EEF2, GAPDH, and PGK1 are the best HKG genes and can be used in the diagnostic panel of Ph-like ALL cases using qPCR at baseline diagnosis.

Autopsy findings of acute erythroid leukemia.

Acute erythroid leukemia (AEL) is an exceedingly uncommon but distinct hematological malignancy that shows neoplastic proliferation of erythroid precursors with maturation arrest and no significant myeloblasts. We describe an autopsy case of this rare entity in a 62-year-old man with co-morbidities. He underwent a bone marrow (BM) examination for pancytopenia during the first outpatient department visit, which revealed an increased number of erythroid precursors with dysmegakaryopoiesis suggesting the possibility of Myelodysplastic syndromes (MDS). Thereafter, his cytopenia got worsened, warranting blood and platelet transfusions. Four weeks later on the second BM examination, AEL was diagnosed based on morphology and immunophenotyping. Targeted resequencing for myeloid mutations revealed TP53 and DNMT3A mutations. He was initially managed along febrile neutropenia with the stepwise escalation of antibiotics. He developed hypoxia attributed to anemic heart failure. Subsequently, he had hypotension and respiratory fatigue pre-terminally and succumbed to his Illness. A complete autopsy showed infiltration of various organs by AEL and leukostasis. Besides, there was extramedullary hematopoiesis, arterionephrosclerosis, diabetic nephropathy (ISN-RPS class II), mixed dust pneumoconiosis, and pulmonary arteriopathy. The histomorphology of AEL was challenging, and the differential diagnoses were many. Thus, this case highlights the autopsy pathology of AEL, an uncommon entity with a strict definition, and its relevant differentials.

'Evaluation of adverse prognostic gene alterations & MRD positivity in BCR::ABL1-like B-lineage acute lymphoblastic leukaemia patients, in a resource-constrained setting.

BACKGROUND: Early detection of BCR::ABL1-like ALL could impact treatment management and improve the overall survival/outcome. BCR::ABL1-like ALL cases are characterised by diverse genetic alterations activating cytokine receptors and kinase signalling. Its detection is still an unmet need in low-middle-income countries due to the unavailability of a patented TLDA assay. METHODS: This study's rationale is to identify BCR::ABL1-like ALLs using the PHi-RACE classifier, followed by the characterisation of underlying adverse genetic alterations in recurrent gene abnormalities negative (RGAneg) B-ALLs (n = 108). RESULTS: We identified 34.25% (37/108) BCR::ABL1-like ALLs using PHi-RACE classifier, characterised by TSLPR/CRLF2 expression (11.58%), IKZF1 (Δ4-7) deletion (18.9%) and chimeric gene fusions (34.61%). In overexpressed TSLPR/CRLF2 BCR::ABL1-like ALLs, we identified 33.33% (1/3) CRLF2::IGH and 33.33% (1/3) EPOR::IGH rearrangements with concomitant JAK2 mutation R683S (50%). We identified 18.91% CD13 (P = 0.02) and 27.02% CD33 (P = 0.05) aberrant myeloid markers positivity, which was significantly higher in BCR::ABL1-like ALLs compared to non-BCR::ABL1-like ALLs. MRD positivity was considerably higher (40% in BCR::ABL1-like vs. 19.29% in non-BCR::ABL1-like ALLs). CONCLUSIONS: With this practical approach, we reported a high incidence of BCR::ABL1-like ALLs, and a lower frequency of CRLF2 alteration & associated CGFs. Recognising this entity, early at diagnosis is crucial to optimise personalised treatment strategies.

Genomic and proteomic characterization of Philadelphia-like B-lineage acute lymphoblastic leukemia: A report of Indian patients.

BACKGROUND: The gold standard for the identification of Philadelphia (Ph)-like acute lymphoblastic leukemia (ALL) patients is gene expression profiling. Because of its diverse nature, its identification is extremely difficult and expensive. On the genomic and proteomic landscape of Ph-like ALL patients, there is a paucity of published literature from developing countries. METHODS: The authors used digital barcoded nCounter NanoString gene expression profiling for its detection, followed by molecular and proteomic characterization using fluorescence in situ hybridization and liquid chromatography-tandem mass spectrometry (LC-MS/MS). RESULTS: The authors found 32.05% Ph-like ALL patients and their median age at presentation was considerably higher than Ph-negative ALL cases (p = .0306). Furthermore, we identified 20% CRLF2 overexpressed cases having 8.33% CRLF2-IGH translocation with concomitant R683S mutation and 8.33% CRLF2-P2RY8 translocation. In 80% of CRLF2 downregulated cases, we identified 10% as having JAK2 rearrangement. Minimal residual disease-positivity was more common in Ph-like ALL cases (55.55% vs. 25% in Ph-negative ALL cases). Immunoglobulin J chain (Jchain), small nuclear ribonucleoprotein SmD1 (SNRPD1), immunoglobulin κ constant (IGKC), NADH dehydrogenase (ubiquinone) 1 α subcomplex subunit 2 (NDUFA2), histone H2AX (H2AFX), charged multivesicular body protein 4b (CHMP4B), and carbonyl reductase (NADPH) (CBR1) proteins were identified to be substantially expressed in Ph-like ALL patients, using LC-MS/MS. Gene enrichment analysis indicated that involvement of spliceosomal mediated messenger RNA splicing pathway and four microRNAs was statistically significant in Ph-like ALL patients. CONCLUSIONS: For the first time, we have described incidence, molecular, and proteomic characterization of Ph-like ALL, in developing nations. PLAIN LANGUAGE SUMMARY: In developing countries, detecting Philadelphia (Ph)-like B-lineage acute lymphoblastic leukemia is complicated and challenging due to its diverse genetic landscape. There is no well-defined and cost-effective methodology for its detection. The incidence of this high-risk subtype is very high in adult cases, and there is an urgent need for its accurate detection. We have developed an online PHi-RACE classifier for its rapid detection, followed by delineating the genomic and proteomic landscape of Ph-like acute lymphoblastic leukemias for the first time in Indian patients.

Autopsy findings of acute erythroid leukemia

ABSTRACT Acute erythroid leukemia (AEL) is an exceedingly uncommon but distinct hematological malignancy that shows neoplastic proliferation of erythroid precursors with maturation arrest and no significant myeloblasts. We describe an autopsy case of this rare entity in a 62-year-old man with co-morbidities. He underwent a bone marrow (BM) examination for pancytopenia during the first outpatient department visit, which revealed an increased number of erythroid precursors with dysmegakaryopoiesis suggesting the possibility of Myelodysplastic syndromes (MDS). Thereafter, his cytopenia got worsened, warranting blood and platelet transfusions. Four weeks later on the second BM examination, AEL was diagnosed based on morphology and immunophenotyping. Targeted resequencing for myeloid mutations revealed TP53 and DNMT3A mutations. He was initially managed along febrile neutropenia with the stepwise escalation of antibiotics. He developed hypoxia attributed to anemic heart failure. Subsequently, he had hypotension and respiratory fatigue pre-terminally and succumbed to his Illness. A complete autopsy showed infiltration of various organs by AEL and leukostasis. Besides, there was extramedullary hematopoiesis, arterionephrosclerosis, diabetic nephropathy (ISN-RPS class II), mixed dust pneumoconiosis, and pulmonary arteriopathy. The histomorphology of AEL was challenging, and the differential diagnoses were many. Thus, this case highlights the autopsy pathology of AEL, an uncommon entity with a strict definition, and its relevant differentials.

Meningoencephalitis in primary antibody deficiency: Our experience from northwest India.

BACKGROUND/OBJECTIVES: Patients with primary antibody deficiency (PAD) are predisposed to develop meningoencephalitis, often considered to be enteroviral. However, there is a paucity of literature on this subject, and there are no studies from developing countries. METHODS: We analyzed our cohort of children with PAD who developed meningoencephalitis. RESULTS: This complication was observed in 13/135 (10.4%) patients with PAD - 5 patients had X-linked agammaglobulinemia (XLA), 7 had common variable immunodeficiency (CVID) and 1 had suspected nuclear factor kappa B essential modulator (NEMO) defect. Mean age at onset of neurological illness was 9.3 years. Presenting features included seizures (n=8), neurodevelopmental delay (n=2), regression of milestones (n=2), and acute flaccid paralysis (n=1). Trough IgG levels were found to be low in 12/13 patients at the time of development of neurological symptoms. Herpes simplex virus (HSV), cytomegalovirus (CMV), and Streptococcus pneumoniae were isolated in 1 each. Eight (72.7%) patients had altered signal hyperintensities in gray matter and deep white matter on magnetic resonance imaging (MRI), while 4 patients showed global cerebral atrophy. All patients were treated with high-dose intravenous immunoglobulin (IVIg). Fluoxetine was given to 3 patients. Eight patients in the present series have died, 3 have recovered with varying degrees of neurological sequelae and 2 patients are showing gradual recovery. CONCLUSIONS: To conclude, meningoencephalitis is an uncommon complication in patients with PAD and is associated with high morbidity and mortality. Early diagnosis of immune deficiency and initiation of replacement immunoglobulin therapy may prevent the development of neurological complications.

Post-transplant cyclophosphamide pharmacokinetics and haploidentical hematopoietic cell transplantation outcomes: an exploratory study.

Pharmacokinetics of cyclophosphamide has been explored to optimize conditioning dosing. We hypothesized that post-transplant cyclophosphamide (PTCy) metabolite carboxy-ethyl phosphoramide mustard (CEPM) pharmacokinetics might impact haploidentical transplantation (haplo-HCT) outcomes. CEPM area under the curve (AUC0-48) was determined by eleven sampling timepoints on day +3/+4 using LC-MS/MS. The median CEPM AUC0-48 in a cohort of 30 patients was 14.2 (14) mg·hr/L. The incidence of severe chronic graft-versus-host disease (GVHD) (73% vs. 11%, p = 0.02), and GVHD-/relapse-free survival (GRFS) was significantly inferior in the CEPM AUC0-48 < 14 mg·hr/L group (54 days vs. 344 days, p = 0.02). There was, however, no difference in grade III-IV acute GVHD (38% vs. 14%, p = 0.12) and overall survival (295 days vs. not reached, p = 0.2). CEPM AUC0-48, is associated with severe chronic GVHD and GRFS post-haplo-HCT in this exploratory study. There is scope for personalizing day + 4 PTCy dose based on day + 3 CEPM AUC0-8.

A Novel CEBPE Variant Causes Severe Infections and Profound Neutropenia.

PURPOSE: Specific granule deficiency (SGD) is a rare inborn error of immunity resulting from loss-of-function variants in CEBPE gene (encoding for transcription factor C/EBPε). Although this genetic etiology has been known for over two decades, only a few patients with CEBPE variant-proven SGD (type I) have been reported. Herein, we describe two siblings with a novel homozygous CEBPE deletion who were noted to have profound neutropenia on initial evaluation. We aimed to evaluate the immunohematological consequences of this novel variant, including profound neutropenia. METHODS: Light scatter characteristics of granulocytes were examined on various automated hematology analyzers. Phagocyte immunophenotype, reactive oxygen species generation, and Toll-like receptor (TLR) signaling were assessed using flow cytometry. Relative expression of genes encoding various granule proteins was studied using RT-PCR. Western blot analysis and luciferase reporter assay were performed to explore variant C/EBPε expression and function. RESULTS: Severe infections occurred in both siblings. Analysis of granulocyte light scatter plots revealed automated hematology analyzers can provide anomalously low neutrophil counts due to abnormal neutrophil morphology. Neutrophils displayed absence/marked reduction of CD15/CD16 expression and overexpression (in a subset) of CD14/CD64. Three distinct populations of phagocytes with different oxidase activities were observed. Impaired shedding of CD62-ligand was noted on stimulation with TLR-4, TLR-2/6, and TLR-7/8 agonists. We demonstrated the variant C/EBPε to be functionally deficient. CONCLUSION: Homozygous c.655_665del variant in CEBPE causes SGD. Anomalous automated neutrophil counts may be reported in patients with SGD type I. Aberrant TLR signaling might be an additional pathogenetic mechanism underlying immunodeficiency in SGD type I.