Florian Weissinger

What is CD4+CD56+ malignancy and how should it be treated?

Summary:CD4+CD56+ malignancy is a rare neoplasm with a typical clinical pattern, an aggressive course and high early relapse rate despite good initial response to chemotherapy. In this review, the impact of different therapeutic approaches on clinical outcome has been studied. We evaluated 91 published cases and our own six patients in terms of clinical features, immunophenotype/cytogenetics and treatment outcome. Treatment was divided into four groups: (A) chemotherapy less intensive than CHOP; (B) CHOP and CHOP-like regimens; (C) therapy for acute leukemia; (D) allogeneic/autologous stem cell transplantation. The median overall survival was only 13 months for all patients. Patients with skin-restricted disease showed no difference in the overall survival from patients with advanced disease (17 and 12 months, respectively). Age ⩾60 years was a negative prognostic factor. Age-adjusted analysis revealed improved survival after high-dose chemo/radiotherapy followed by allogeneic stem cell transplantation when performed in first complete remission. This therapeutic approach should be recommended for eligible patients with CD4+CD56+ malignancy. For older patients the best treatment option is still unknown.

Central venous catheter (CVC)-related infections in neutropenic patients

Catheter-related infections cause considerable morbidity in hospitalised patients. The incidence does not seem to be higher in neutropenic patients than in non- neutropenic patients. Gram-positive bacteria (coagulase-negative staphylococci, Staphylococcus aureus) are the most frequently cultured pathogens, followed by Candida species. In contrast, Gram-negative bacteria play only a minor role in catheter-related infections. Positive blood cultures are the cornerstone in the diagnosis of catheter-related infections, while local signs of infection are only rarely present. However, a definite diagnosis generally requires the removal of the catheter and its microbiological examination. The role plate method with semiquantitative cultures (Maki) has been established as standard in most laboratories. Other standard procedures use quantitative techniques (Sherertz, Brun-Buisson) and are more sensitive. For therapy of catheter-related infections, antibiotics are administered according to the susceptibility of the cultured organism. Routine administration of gylcopepticed antibiotics is not indicated. Removal of the catheter has to be considered in any case of suspected catheter-related infection and is obligatory in Staphylococcus aureus and Candida infections. Tunnel or pocket infection of long-term catheters is always an indication for removal. In the future, the rate of catheter-related infections in neutropenic patients may be reduced by the use of catheters coated with antimicrobial agents.

Antimicrobial therapy of febrile complications after high-dose chemo-/radiotherapy and autologous hematopoietic stem cell transplantation

Infectious complications occur in 60–100% of patients following high-dose chemotherapy (HDC) and autologous hematopoietic stem cell transplantation (HSCT), and are commonly caused by Gram-negative aerobic bacteria (such as Pseudomonas aeruginosa and enterobacteriaceae) and Gram-positive cocci (such as enterococci, streptococci and staphylococci), which should be covered by empiric first-line antibiotic therapy. Less frequently, infections are caused by fungi and anaerobic bacteria, and initial therapy does not necessarily have to cover coagulase-negative staphylococci, oxacillin-resistant S. aureus (MRSA), anaerobic bacteria and fungi. Patients who already receive antibiotics and develop pulmonary infiltrates should immediately be treated with systemic antifungals. Patients with fever and diarrhea or other signs and symptoms of gastrointestinal or perianal infection should be treated with antibiotics covering anaerobic bacteria and enterococci. Clinically stable patients with skin infections or central venous catheter-related infections can be treated with standard empiric antibiotic therapy including a beta-lactam active against Pseudomonas aeruginosa with or without an aminoglycoside, and should only receive glycopeptides if they do not respond to first-line therapy within 72 hours, become clinically unstable, have severe mucositis, or when resistance against the empiric antibiotics is demonstrated. Recombinant hematopoietic growth factors should not be added routinely but may be considered in life-threatening situations such as invasive pulmonary mycoses or sepsis.

Bacterial infection of human hematopoietic stem cells induces monocytic differentiation

Differentiation of hematopoietic stem cells (HSCs) can be influenced by different stimuli, including cytotoxic agents, certain cytokines, and contact with pathogens. Infection may result in dysregulation of these important progenitor cells and therefore interfere with the availability of blood cells. In this study we analyzed the effect of bacterial infection on HSCs concerning surface marker expression and cytokine release. Listeria monocytogenes and Yersinia enterocolitica accelerated maturation of hematopoietic progenitor cells along the myeloid lineage, as demonstrated by the upregulation of CD13, CD14, and costimulatory signals. By screening cytokine secretion, granulocyte-macrophage colony-stimulating factor, interleukin (IL)-6, IL-8, IL-10, IL-12, and tumor necrosis factor-alpha were found to be induced by bacterial infection. These data indicate that infection of HSCs with L. monocytogenes and Y. enterocolitica affects the differentiation of CD34(+) hematopoietic progenitors in vitro and may lead to secretion of cytokines that can influence the HSC differentiation capacity and immune response.

Aseptic necrosis of both femoral heads as first symptom of chronic myelogenous leukemia.

Abstract. Chronic myelogenous leukemia (CML) is a disease of the elderly; in rare cases it occurs in childhood or adolescence. One complication at primary diagnosis is leukostasis, which usually causes respiratory, retinal, or central nervous symptoms. In this report we describe the case of a 24-year-old woman who developed aseptic necrosis of both femoral heads, which was successfully treated by bore holes in the femoral heads. This is a very rare complication of severe leukostasis, leading to the diagnosis of CML in this case. To our knowledge, this is the first case of an adult patient showing aseptic necrosis of femoral heads caused by leukostasis.

A lymphohistiocytic variant of anaplastic large cell lymphoma with demonstration of the t(2;5)(p23;q35) chromosome translocation

Cytogenetic investigations were performed in a case of a nodal malignant non‐Hodgkins lymphoma. Histopathological analysis from an involved lymph node as well as from a skin biopsy revealed a lymphohistiocytic variant of CD30‐positive anaplastic large cell lymphoma (ALCL). A t(2;5)(p23;q35) chromosome translocation could be observed in all metaphases analysed. This finding was confirmed both by RT‐PCR analysis of the NPM/ALK fusion protein and by positive staining with the p80NPM/ALK antibody. To the best of our knowledge, this is the first report of a t(2;5) documented by classic cytogenetics in the lymphohistiocytic variant of ALCL.