Ewerton Marques Maggio

Common and differential chemokine expression patterns in rs cells of NLP, EBV positive and negative classical hodgkin lymphomas

Hodgkin lymphoma (HL) is characterized by a minority of neoplastic cells, the so‐called Reed‐Sternberg (RS) cells and a vast majority of reactive cells. RS cells produce chemokines that can attract subsets of peripheral blood cells into HL tissues. To gain insight in the chemokines involved in HL, 16 chemokines were selected based on their ability to recruit different subsets of cells. Five HL, 5 non‐HL‐derived cell lines, 22 HL, 5 non‐HL and 3 control tissues were analyzed by reverse transcriptase‐polymerase chain reaction (RT‐PCR). Products for 13 of these 16 chemokines were detected in 1 or more of the cell lines tested. No or only very faint signals were obtained in HL for CXCL12, CCL7 and CCL8, but CXCL10, CCL5, CCL13, CCL17 and CCL22 were highly or differentially expressed in HL cell lines and tissues. Immunohistochemistry was performed with antibodies reactive with the latter 5 chemokines on paraffin sections of 21 cases of HL. CCL17 and CCL22 had the highest signals in RS cells at gene expression and at protein levels. CCL17 was specific for the classic HL subtypes, whereas CCL22 also had low signals in NLP samples, as well as in some non‐HL. CXCL10 was expressed in a large proportion of HL cases with a predominant expression in EBV‐positive cases. The results indicate that RS cells produce a complex pattern of chemokines that are involved in the recruitment of reactive cells and contribute to the paradox of an extensive but ineffective host immune response.

TP53 gene mutations in Hodgkin lymphoma are infrequent and not associated with absence of Epstein‐Barr virus

Reed‐Sternberg (RS) cells, the neoplastic cells of Hodgkin lymphoma (HL) have clonal immunoglobulin gene rearrangements. The presence of somatic mutations suggests a germinal center origin, whereas the presence of crippling mutations suggests rescue of RS precursors from apoptosis by a transforming event. Epstein‐Barr virus (EBV), which can be detected in 30–50% of HL cases, probably plays a role in this transforming event. The frequent presence of p53 protein expression in RS cells also suggests a role of the TP53 gene in this escape from apoptosis. Although mutations of the TP53 gene occur infrequently in RS cells, it has been suggested that in EBV‐negative cases this gene mutation may be fundamental for the inhibition of apoptosis. In this study, we tested the hypothesis that there is an inverse correlation between the presence of TP53 gene mutations and the presence of EBV. In 21 of 67 cases EBV encoded small RNA (EBER)1‐2 mRNAs were detected. Immunostaining for p53 protein revealed positivity in all 67 cases with variable percentages of positive cells and staining intensity. Screening for mutations in exons 5, 6, 7 and 8 of the TP53 gene in single RS cells obtained by laser microdissection from 26 HL specimens and 4 HL‐derived cell lines revealed mutations in 2 of 15 EBV‐positive cases and in 1 of 11 EBV‐negative cases. Our results confirm the presence of infrequent (11.5%) TP53 gene mutations in HL and suggest that mutations of the TP53 gene are not correlated to the absence of EBV.

FAS gene mutation in a case of autoimmune lymphoproliferative syndrome type IA with accumulation of gamma delta+ T cells

A 6-month-old girl presented to the hospital with cervical lymphadenopathy and hepatosplenomegaly. She was known to have an enlarged spleen, anemia, and thrombocytopenia since the age of 1 month. A lymph node biopsy showed a diffuse proliferation of blasts with few remnants of follicles. The blasts were CD3+CD57+CD4-CD8-, consistent with the usual autoimmune lymphoproliferative syndrome phenotype. However, these double negative T cells stained positive for gammadelta T-cell receptors, whereas double negative T cells in patients with autoimmune lymphoproliferative syndrome usually bear alphabeta T-cell receptor. Mutation analysis of the FAS gene revealed a mutation in the death domain of the FAS gene, which is a frequent finding in patients with autoimmune lymphoproliferative syndrome. Based on these results, the diagnosis of autoimmune lymphoproliferative syndrome was established. RT-PCR analysis of the affected lymph node tissue revealed a strong upregulation of interleukin 10 and a moderate upregulation of interferon-gamma expression compared with normal tissue. Our findings indicate that autoimmune lymphoproliferative syndrome can result in a prominent proliferation of gammadelta+ double negative T cells. It is important to distinguish this benign polyclonal proliferation from neoplastic gammadelta+ T-cell proliferations, such as hepatosplenic gammadelta T-cell lymphomas. Factors contributing to the accumulation of these gammadelta+ double negative T cells may be an unidentified infection in combination with the young age of onset in this patient.

Clindamycin Affects Group A Streptococcus Virulence Factors and Improves Clinical Outcome

Group A Streptococcus (GAS) has acquired an arsenal of virulence factors, promoting life-threatening invasive infections such as necrotizing fasciitis. Current therapeutic regimens for necrotizing fasciitis include surgical debridement and treatment with cell wall-active antibiotics. Addition of clindamycin (CLI) is recommended, although clinical evidence is lacking. Reflecting the current clinical dilemma, an observational study showed that only 63% of the patients with severe invasive GAS infection received CLI. This work thus aimed to address whether CLI improves necrotizing fasciitis outcome by modulating virulence factors of CLI-susceptible and CLI-resistant GAS in vitro and in vivo. Treatment with CLI reduced extracellular DNase Sda1 and streptolysin O (SLO) activity in vivo, whereas subinhibitory CLI concentrations induced expression and activity of SLO, DNase, and Streptococcus pyogenes cell envelope protease in vitro. Our in vivo results suggest that CLI should be administered as soon as possible to patients with necrotizing fasciitis, while our in vitro studies emphasize that a high dosage of CLI is essential.

HBME-1 expression in hyalinizing trabecular tumours of the thyroid gland.

Hyalinizing trabecular tumour (HTT) is a rare thyroid neoplasm with a trabecular growth pattern, marked intratrabecular hyalinization and nuclear features of papillary thyroid carcinoma (PTC). Immunohistochemical HBME‐1 expression was reported recently in PTC, but not in HTT. To clarify further the value of HBME‐1 expression as a tool in differential diagnosis, we investigated the immunophenotype of HTT.

Immunoglobulin Attenuates Streptokinase-Mediated Virulence in Streptococcus dysgalactiae Subspecies equisimilis Necrotizing Fasciitis

A clinicalStreptococcus dysgalactiae equisimilis strain secreting high levels of streptokinase promoted severe disease in a patient lacking anti-streptokinase antibodies. Exogenous immunoglobulins efficiently blocked streptokinase-mediated fibrinolysis in vitro and attenuated streptokinase-mediated virulence in a necrotizing fasciitis mouse model.

An unusual cause of febrile hepatitis.

We describe the case of a 51-year-old man with recently diagnosed ulcerative colitis who developed fever and elevated liver enzymes as well as cholestasis a few weeks after starting treatment with mesalazine. As no obvious cause was found and fever persisted, liver biopsy was performed and revealed granulomatous hepatitis. The patient recovered completely after cessation of mesalazine, so that a drug-induced granulomatous hepatitis after exclusion of other differential diagnoses in an extensive work up was assumed. The present case demonstrates that even though drug-induced liver injury due to mesalazine is rare, it should be considered in unclear cases and lead to prompt discontinuation of mesalazine.

Treatment of non-alcoholic steatohepatitis patients with vitamin D: a double-blinded, randomized, placebo-controlled pilot study

Abstract Background: Non-alcoholic steatohepatitis (NASH) is defined by liver inflammation and consecutive fibrotic damage caused by a deposition of fat in the liver. No licensed medical treatments exist and lifestyle modification is difficult to incorporate into everyday life. We investigated the efficacy and safety of a 48-week treatment with vitamin D3 in NASH patients. Methods: Histologically determined NASH patients with elevated alanine aminotransferase (ALT) and decreased 25-OH vitamin D level at baseline received vitamin D3 or placebo orally over a 48-week period. The primary endpoint of this study was the change in ALT from baseline to the end-of-treatment. Steatohepatitis was categorized according to the Steatosis, Activity and Fibrosis Score and disease activity was assessed using the NAFLD activity score. Results: Serum 25-OH vitamin D levels significantly increased only in the vitamin D3 group over the 48-week treatment phase indicating compliance. In contrast to placebo, patients in the vitamin D group had markedly decreased ALT levels after the end-of-treatment phase. A significant decrease during treatment with vitamin D was also observed for cytokeratin-18 fragments compared with placebo. The study was not powered to detect changes in histological score, hence only descriptive results for histopathological characteristics are available. Conclusions: Treatment with 2100 IE vitamin D q.d. over 48 weeks was well tolerated and led to a significant improvement of serum ALT levels in patients with hypovitaminosis D and histology-proven NASH as the primary endpoint together with a trend toward reduction of hepatic steatosis, which was not significant due to a small number of available biopsy specimens.

Simultaneous endoscopic full-thickness resection of two synchronous colonic granular cell tumours

Granular cell tumours (GCTs) are rare soft tissue tumours originating from Schwann cells. Due to potential malignant transformation, complete endoscopic resection should be aimed for. We report on a 49-year-old patient with two synchronous GCTs found in the caecum and the ascending colon, respectively. Synchronous endoscopic full-thickness resection (EFTR) using an all-in-one full-thickness resection device (FTRD) was performed under propofol sedation. Completeness of resection was proven histologically. No adverse events occurred. We report safe and complete simultaneous EFTR of two synchronous colonic GCTs.

Human streptococcal necrotizing fasciitis histopathology mirrored in a murine model

Streptococcal necrotizing fasciitis (NF) causes high morbidity and mortality despite state-of-the-art therapy. Low incidence and rapid disease progression, necessitating immediate initiation of therapy, have proven challenging aspects for setting up prospective randomized trials. This has resulted in little therapeutic progress over the past decade. The validation of reliable murine NF models to study both pathogenesis and optimized therapeutic regimens of streptococcal NF are thus essential. In this study, we characterized a murine NF model and compared the pathology with an in-depth tissue analysis of streptococcal NF in patients. We found that the streptococcal murine NF model closely reflected all histologic characteristics encountered in human streptococcal NF. This murine NF model helps understanding of human NF pathology better in a time-dependent manner and will allow studying novel therapeutic options in the future.