Diagnostic utility of STAT6YE361 expression in classical Hodgkin lymphoma and related entities.

Although the distinction of classical Hodgkin lymphoma from nodular lymphocyte predominant Hodgkin lymphoma using morphology and immunostains is straightforward in most instances, occasional cases pose diagnostic challenge. We sought to determine the utility of the novel YE361 STAT6 rabbit monoclonal antibody in Hodgkin lymphoma and diagnostically challenging B- and T-cell non-Hodgkin lymphoma entities with Hodgkin-like features. Cases from seven institutions included: 57 classical Hodgkin lymphomas (31% EBV+), 34 nodular lymphocyte predominant Hodgkin lymphomas, 34 mimicking B- and T-cell non-Hodgkin lymphomas, and 7 reactive lymphoproliferations. After review of histology, STAT6YE361 immunostaining was performed. The intensity and spatial localization of immunopositivity was assessed in neoplastic cells. Additional FISH for programmed death ligand-1 (PD-L1) was performed in one patient in paired treatment-naive and relapse biopsy tissues. Two STAT6YE361 immunopositive cases were examined by whole-exome sequencing after flow sorting to assess mutations in STAT6 pathway genes. Most classical Hodgkin lymphomas showed nuclear staining for STAT6YE361 [46/57 cases (80%)] on Hodgkin cells. Staining was exclusively nuclear in a minority [12/46 (26%)], while dual nuclear and cytoplasmic localization was more common [34/46 (74%)]. In contrast, all nodular lymphocyte predominant Hodgkin lymphomas [0/34 (0%)] were negative for nuclear STAT6YE361 staining on the lymphocyte predominant cells. Within B- and T-cell non-Hodgkin lymphomas, nuclear STAT6YE361 was seen in: B-cell lymphoma unclassifiable with features intermediate between diffuse large B-cell lymphoma and classical Hodgkin lymphoma, and in primary mediastinal large B-cell lymphoma. Strong PD-L1 gene amplification was noted in the paired cHL and relapse B-cell lymphoma unclassifiable with features intermediate between diffuse large B-cell lymphoma and classical Hodgkin lymphoma, although STAT6YE361 was negative in both biopsies. Whole-exome sequencing identified mutations in B2M, XPO1, and ITPKB as well CISHP213L (in the STAT pathway) in one classical Hodgkin lymphoma patient positive for nuclear STAT6YE361 although no underlying STAT6 mutations were observed in either sample examined. STAT6YE361 nuclear staining has 100% positive predictive value and 85.7% negative predictive value in confirming or excluding classical Hodgkin lymphoma diagnosis in the distinction from nodular lymphocyte predominant Hodgkin lymphoma and other benign and malignant entities.

Intracranial hemorrhage as initial manifestation of plasma cell myeloma: A case report.

This is the case of a previously healthy 48 year-old male whom presented with mild confusion, low-grade headache, and left sided weakness. Computed tomography of the head revealed a large acute right frontal lobe intracranial hemorrhage (ICH) and intraventricular extension, with normal vascular imaging. Initial laboratory testing was inconsequential. The patient required emergent evacuation, with pathology revealing only elements of a hematoma. Further laboratory testing and bone marrow biopsy results confirmed the diagnosis of plasma cell myeloma. Other systemic signs/symptoms of this disease were notably absent. This report provides the first description of an ICH as the presenting manifestation of plasma cell myeloma (PCM; multiple myeloma).

Reengineering Critical Laboratory Testing for Timely Chemotherapeutic Management.

BACKGROUND: Delivery of cytotoxic therapy is a complex multifaceted process that involves harmonized collaboration between all systems involved. Optimizing laboratory turnaround time (TAT) ensures timely delivery of chemotherapy, which potentially translates into improved patient outcomes and satisfaction. In this study, we aimed to reduce the laboratory TAT for key laboratory tests to optimize the timely administration of chemotherapy. METHODS: TAT data for complete blood count (CBC) and comprehensive metabolic panel (CMP) included specimen collection to receipt (Col-Rcv), specimen receipt to result release (Rcv-Res), and the overall TAT from specimen collection to result release (Col-Res). Work flows were reconfigured to transport CBC specimens directly to the hematology laboratory after collection and to treat all CMP samples from chemotherapy clinics as urgent [i.e., shortest turnaround time (STAT)]. From the CMP, total bilirubin and creatinine-the 2 key analytes for liver and renal toxicity assessment before chemotherapy drug administration-were analyzed on ABL 800 whole blood analyzers to further improve the laboratory TAT. RESULTS: CBC showed a significant reduction in the median (Col-Res) TAT to 16 min (P < 0.0001). For CMP, by processing all specimens as STAT samples, the median (Col-Res) TAT was reduced from 74 min to 54 min (P < 0.0001), and it was further reduced to 9 min (P < 0.0001) for total bilirubin and creatinine. CONCLUSION: Careful work flow analysis and reengineering of preanalytical and analytical process for key laboratory tests significantly reduced median overall TAT to <20 min, which helped facilitate more timely delivery of chemotherapy, without necessitating the construction of a satellite laboratory.

Identification of a structurally novel BTK mutation that drives ibrutinib resistance in CLL.

Ibrutinib (ibr), a first-in-class Bruton tyrosine kinase (BTK) inhibitor, has demonstrated high response rates in both relapsed/refractory and treatment naïve chronic lymphocytic leukemia (CLL). However, about 25% of patients discontinue ibrutinib therapy at a median follow-up of 20 months and many patients discontinue the treatment due to leukemia progression or Richter transformation. Mutations affecting the C481 residue of BTK disrupt ibrutinib binding and have been characterized by us and others as the most common mechanism of ibrutinib resistance. Thus far, all described BTK mutations are located in its kinase domain and mutations outside this domain have never been described. Herein, we report a patient whose CLL progressed, was salvaged with ibrutinib and then relapsed. Serial analysis of samples throughout patient's clinical course identified a structurally novel mutation (BTKT316A) in the SH2 domain, but not kinase domain, of Bruton tyrosine kinase which was associated with disease relapse. Functionally, cells carrying BTKT316A show resistance to ibrutinib at both cellular and molecular levels to a similar extent as BTKC481S. Our study lends further insight into the diverse mechanisms of ibrutinib resistance that has important implications for the development of next-generation BTK inhibitors as well as mutation detection in relapsed patients.

Neonatal Thrombocytopenia: Etiology and Diagnosis.

Neonatal thrombocytopenia has a broad range of possible etiologies. In this review, an asymptomatic newborn infant was found to have severe thrombocytopenia on laboratory testing for limited sepsis evaluation. The differential diagnosis for thrombocytopenia in the newborn period is discussed, along with recommendations for initial evaluation and follow up of isolated thrombocytopenia in an otherwise well-appearing infant. The clinician should be aware of findings associated with unusual causes of thrombocytopenia that should prompt additional evaluation in the nursery or in the general pediatrician's office. In this illustrative case, a high index of suspicion allowed early diagnosis of Wiskott-Aldrich syndrome and prompt curative therapy by stem cell transplant.

Bile cast nephropathy is a common pathologic finding for kidney injury associated with severe liver dysfunction.

Cholemic nephrosis represents a spectrum of renal injury from proximal tubulopathy to intrarenal bile cast formation found in patients with severe liver dysfunction. However, the contribution of this diagnosis has been largely forgotten in the modern literature. To more precisely define this, we conducted a clinicopathologic study of 44 subjects (41 autopsies and 3 renal biopsies) from jaundiced patients at the University of Chicago. Of these, 24 patients had bile casts with involvement of distal nephron segments in 18 mild cases and extension to proximal tubules for 6 severe cases. Eleven of 13 patients with hepatorenal syndrome and all 10 with cirrhosis (due to alcoholism) had tubular bile casts. These casts significantly correlated with higher serum total and direct bilirubin levels, and a trend toward higher serum creatinine, AST, and ALT levels. Bile casts may contribute to the kidney injury of severely jaundiced patients by direct bile and bilirubin toxicity, and tubular obstruction. Both mechanisms are analogous to the injury by myeloma or myoglobin casts. Accounting for the presence of renal bile casts provides a more complete representation of the renal injury that can occur in this unique clinical setting. Thus, bile cast nephropathy is an appropriate term for the severe form of injury observed in the spectrum of cholemic nephrosis. Additional studies are needed to establish the significance of this parameter for patient management in different clinical settings.

Activin induces tactile allodynia and increases calcitonin gene-related peptide after peripheral inflammation.

Calcitonin gene-related peptide (CGRP) is a sensory neuropeptide important in inflammatory pain that conveys pain information centrally and dilates blood vessels peripherally. Previous studies indicate that activin A increases CGRP-immunoreactive (IR) sensory neurons in vitro, and following wound, activin A protein increases in the skin and more neurons have detectable CGRP expression in the innervating dorsal root ganglion (DRG). These data suggest some adult sensory neurons respond to activin A or other target-derived factors with increased neuropeptide expression. This study was undertaken to test whether activin contributes to inflammatory pain and increased CGRP and to learn which neurons retained plasticity. After adjuvant-induced inflammation, activin mRNA, but not NGF or glial cell line-derived neurotrophic factor, increased in the skin. To examine which DRG neurons increased CGRP immunoreactivity, retrograde tracer-labeled cutaneous neurons were characterized after inflammation. The proportion and size of tracer-labeled DRG neurons with detectable CGRP increased after inflammation. One-third of CGRP-IR neurons that appear after inflammation also had isolectin B4 binding, suggesting that some mechanoreceptors became CGRP-IR. In contrast, the increased proportion of CGRP-IR neurons did not appear to come from RT97-IR neurons. To learn whether central projections were altered after inflammation, CGRP immunoreactivity in the protein kinase Cgamma-IR lamina IIi was quantified and found to increase. Injection of activin A protein alone caused robust tactile allodynia and increased CGRP in the DRG. Together, these data support the hypothesis that inflammation and skin changes involving activin A cause some sensory neurons to increase CGRP expression and pain responses.