Clinical practice recommendations for infectious disease management of diabetic foot infection (DFI) - 2023 SPILF

In march 2020, the International Working Group on the Diabetic Foot (IWGDF) published an update of the 2015 guidelines on the diagnosis and management of diabetic foot infection (DFI). While we (the French ID society, SPILF) endorsed some of these recommendations, we wanted to update our own 2006 guidelines and specifically provide informative elements on modalities of microbiological diagnosis and antibiotic treatment (especially first- and second-line regiments, oral switch and duration). The recommendations put forward in the present guidelines are addressed to healthcare professionals managing patients with DFI and more specifically focused on infectious disease management of this type of infection, which clearly needs a multidisciplinary approach. Staging of the severity of the infection is mandatory using the classification drawn up by the IWGDF. Microbiological samples should be taken only in the event of clinical signs suggesting infection in accordance with a strict preliminarily established protocol. Empirical antibiotic therapy should be chosen according to the IWGDF grade of infection and duration of the wound, but must always cover methicillin-sensitive Staphylococcus aureus. Early reevaluation of the patient is a fundamental step, and duration of antibiotic therapy can be shortened in many situations. When osteomyelitis is suspected, standard foot radiograph is the first-line imagery examination and a bone biopsy should be performed for microbiological documentation. Histological analysis of the bone sample is no longer recommended. High dosages of antibiotics are recommended in cases of confirmed osteomyelitis.

Can we rely on histopathological results for the diagnostic of prosthetic joint infection?

BACKGROUND

Histopathology is one of the diagnostic criteria for prosthetic joint infection (PJI) proposed by all academic societies. The aim of this study was to compare histopathological and microbiological results from samples taken intraoperatively at the same site in patients with suspected or proven PJI.

PATIENTS AND METHODS

We conducted a monocenter retrospective study including all patients having undergone surgery from 2007 to 2015 with suspected or proven PJI. During surgery, both histopathological and microbiological samples were taken. Patients with a history of antimicrobial treatment 2 weeks prior to surgery were excluded. We considered as major criteria and gold standard for PJI diagnosis the presence of a sinus tract communication and/or the same microorganism in at least two cultures.

RESULTS

Finally, 181 patients who underwent 309 surgeries were included. The median number of samples per surgery was 4 (interquartile range (IQR) = 3-5) for histopathology and 5 (IQR=4-6) for microbiology. Major criteria were observed in 177 patients (57.3%), while positive histology in at least one intraoperative sample was present in 119 (38.5%). The concordance was 74%. The sensitivity and specificity of histopathology were 61% and 92% respectively. Available "histopathology-culture" sample pairs numbered 1247. Among them, positive histopathology was found in 292 samples (23%) and culture in 563 (45%). Concordance was 64%. The highest correlation was observed for very early infection (< 1 month) (OR: 9.1, 95% CI: 3.6-23) and for virulent microorganisms, such as Staphylococcus aureus (OR: 7.8, 95% CI: 5.2-11.8), Streptococci (OR:7.8; 95% CI: 4-15.2) or Enterobacterales (OR: 7.4; 95% CI: 4.2-13.1).

CONCLUSION

Histopathologic examination is a valuable criterion for PJI diagnosis, but it may lack sensitivity for chronic infections or due to low-virulence pathogens.

Characteristics of Enterobacter cloacae prosthetic joint infections

OBJECTIVES

Enterobacter cloacae prosthetic joint infections (PJI) are rare and poorly documented.

PATIENTS AND METHODS

We conducted a retrospective and monocentric study in an orthopedic unit supporting complex bone and joint infections. Between 2012 and 2016 we collected background, clinical, biological, and microbiological data from 20 patients presenting with prosthetic joint infection and positive for E. cloacae, as well as data on their surgical and medical treatment and outcome.

RESULTS

Infections were localized in the hip (n=14), knee (n=5), or ankle (n=1). The median time between arthroplasty and septic revision was three years. Fourteen patients (70%) had undergone at least two surgeries due to previous prosthetic joint infections. The median time between the last surgery and the revision for E. cloacae infection was 31 days. Eleven patients (55%) were infected with ESBL-producing strains. The most frequently used antibiotics were carbapenems (n=9), cefepime (n=7), quinolones (n=7), and fosfomycin (n=4). The infection was cured in 15 patients (78.9%) after a 24-month follow-up. Five patients had a recurrent infection with another microorganism and four patients had a relapse of E. cloacae infection. The global success rate was 52.7% (58.3% for DAIR and 75% for DAIR+ciprofloxacin).

CONCLUSION

Prosthetic joint infections due to E. cloacae usually occur early after the last prosthetic surgery, typically in patients with complex surgical and medical histories. The success rate seems to be increased when DAIR is associated with ciprofloxacin.

Direct-acting antiviral treatment against hepatitis C virus infection in HIV-Infected patients - "En route for eradication"?

OBJECTIVES

Direct-Acting Antivirals (DAAs) opened a new era in HCV treatment. We report the impact of HCV treatment in French HIV-HCV coinfected patients.

METHODS

All HIV-HCV patients from the Dat'AIDS cohort followed between 2012 and 2015 were included. HCV status was defined yearly as naive, spontaneous cure, sustained virological response (SVR12), failure or reinfection.

RESULTS

Among 32,945 HIV-infected patients, 15.2% were positive for anti-HCV antibodies. From 2012 to 2015, HCV incidence rate increased from 0.35%PY to 0.69%PY in MSM, while median incidence was 0.08%PY in other patients. Median reinfection rate was 2.56%PY in MSM and 0.22%PY in other patients. HCV treatment initiation rate rose from 8.2% in 2012 to 29.6% (48.0% in pre-treated patients vs 22.6% in naïve patients). SVR12 rate increased from 68.7% to 95.2%. By the end of 2015, 62.7% of the patients were cured either spontaneously or following SVR.

CONCLUSIONS

HCV treatment dramatically increased in HIV-HCV patients in France from 2012 to 2015 resulting in HCV cure in nearly two-thirds of the patients in this cohort. Combined with a declining HCV prevalence, the prevalence of active HCV infection among HIV patients will drastically decrease in the forthcoming years.

Bacillus cereus infection: 57 case patients and a literature review

OBJECTIVES

We aimed to study the characteristics of patients presenting with a Bacillus cereus infection in a university hospital.

METHODS

We performed a retrospective analysis of the clinical, biological, and treatment-related data of patients hospitalized in our university hospital between January 1st, 2008 and December 31st, 2012 and diagnosed with a B. cereus infection. We identified a subgroup of patients presenting with bacteremia and looked for risk factors for death within that group of patients.

RESULTS

We included 57 patients in our study; 31 (54.4%) were hospitalized in a medical ward. We identified 24 bacteremia case patients, including 17 patients presenting with bacteremia alone (29.8%). Other frequently observed infection sites were skin infections (16; 28.1%) and bone and joint infections (10; 17.5%). We recorded 9 deaths (11.8%); 2 patients, despite being on an appropriate antibiotic therapy, died from a medical device-related infection that had not been removed. The empirical administration of a beta-lactam antibiotic was significantly associated with death (P=0.022). Three patients presenting with recurrent bacteremia were identified. The patients only recovered once the infected device had been removed.

CONCLUSION

B. cereus infections may have various clinical presentations. Prospective data is needed to put forward a consensual treatment approach and guide physicians in choosing the appropriate antibiotic therapy and in removing the infected device.

A comparison of monomicrobial versus polymicrobial Enterococcus faecalis bacteriuria in a French University Hospital

Enterococci are of considerable relevance in the hospital setting. Their most common location is the urinary tract, where they may be responsible for both colonization and infections. They are often associated with the presence of other microorganisms. The aim was to compare monomicrobial and polymicrobial Enterococcus faecalis bacteriuria. A retrospective study was performed on the demographic, clinical, and laboratory data of 299 patients who had presented with E. faecalis bacteriuria in 2012 at a University Hospital. The bacteriuria was polymicrobial in 46.1 % of cases and in 36.4 % of cases was responsible for a urinary tract infection. Infections appeared to be more prevalent in the polymicrobial than the monomicrobial group (42 % vs 32 %, p = 0.06). Half of the patients who presented with urinary tract colonization received antibiotic treatment (54/ out of 10). A multivariate analysis adjusted for age (adjusted odds ratio [AOR] = 1.02 per year, p = 0.006), gender (AOR = 2.2, p = 0.007), and clinical classification (colonization or infection, AOR = 1.6, p = 0.091), showed that diabetes mellitus (AOR = 2.0, p = 0.04), hospital length of stay exceeding 28 days (AOR = 2.0, p = 0.03), and presence of a urinary catheter (AOR = 2.4, p = 0.001) were all factors associated with polymicrobial E. faecalis bacteriuria. A reduction in the length of hospital stay and the use of urinary catheters would appear to be required to decrease the incidence of urinary tract colonization and infections by polymicrobial E. faecalis. Improper use of antibiotics to treat urinary tract colonization remains a major concern.

The features of infectious diseases departments and anti-infective practices in France and Turkey: a cross-sectional study

The aim of this study was to assess the infectious diseases (ID) wards of tertiary hospitals in France and Turkey for technical capacity, infection control, characteristics of patients, infections, infecting organisms, and therapeutic approaches. This cross-sectional study was carried out on a single day on one of the weekdays of June 17-21, 2013. Overall, 36 ID departments from Turkey (n = 21) and France (n = 15) were involved. On the study day, 273 patients were hospitalized in Turkish and 324 patients were followed in French ID departments. The numbers of patients and beds in the hospitals, and presence of an intensive care unit (ICU) room in the ID ward was not different in both France and Turkey. Bed occupancy in the ID ward, single rooms, and negative pressure rooms were significantly higher in France. The presence of a laboratory inside the ID ward was more common in Turkish ID wards. The configuration of infection control committees, and their qualifications and surveillance types were quite similar in both countries. Although differences existed based on epidemiology, the distribution of infections were uniform on both sides. In Turkey, anti-Gram-positive agents, carbapenems, and tigecycline, and in France, cephalosporins, penicillins, aminoglycosides, and metronidazole were more frequently preferred. Enteric Gram-negatives and hepatitis B and C were more frequent in Turkey, while human immunodeficiency virus (HIV) and streptococci were more common in France (p < 0.05 for all significances). Various differences and similarities existed in France and Turkey in the ID wards. However, the current scene is that ID are managed with high standards in both countries.

[Non-antibiotic anti-infectious treatments in urology]

OBJECTIVE

To define the terms of use of pesticides, antifungal, antiviral and antiseptic treatments in urology.

MATERIALS AND METHODS

A literature search was conducted on MEDLINE for all these treatments used in urology. The molecules were classified by family. Modes of action, indications in urology and adverse effects have been detailed. Authorisation files were consulted and then complemented by a literature analysis.

RESULTS

Although parasitic or viral diseases are uncommon in urology, their specific treatment deserves a thorough knowledge of pesticide and antiviral molecules. Antifungal treatments are regularly used in urology with special features to know to improve the efficacy/safety ratio. Antiseptics are used daily in urology and a better understanding of these molecules allows better use.

CONCLUSION

Beyond antibiotics, antiviral, antiparasitic and antifungal deserve a thorough knowledge. Antiseptic although used daily have features little known.

[Guidelines for blood transfusion teaching to medical laboratory technology students]

PURPOSE OF THE STUDY

The new French law about clinical laboratory medicine, the requirements of the ISO/CEI 15189 standard, the numerous abilities expected from the medical laboratory technologists and their involvement in blood bank management has led the working group "Recherche et démarche qualité" of the French Society of Blood Transfusion to initiate an inventory of blood transfusion teaching syllabus for medical laboratory technology students and to propose transfusion medicine teaching guidelines.

MATERIAL AND METHODS

Seven worksheets have been established for that purpose including red blood cell antigen typing and antibody screening, blood sampling in immunohaematology, automation, clinical practices, blood products, blood delivery and haemovigilance.

RESULTS

These guidelines aim at contributing to the harmonization of transfusion medicine teaching and at providing objective elements to the medical laboratory managers regarding the practical and theoretical skills of theirs collaborators.

Lymphocyte volume and conductivity indices of the haematology analyser CoulterR GEN.STM in lymphoproliferative disorders and viral diseases

The haematology analyser Coulter GEN.S gives a set of data -'positional parameters'- defining white blood cell (WBC) populations by mean of index values (mean and standard deviation of volume, conductivity and scatter, used to identify the WBC populations). The volume and conductivity parameters related to the lymphocytes were analysed at diagnosis in patients suffering from chronic B-lymphocytic leukaemia (B-CLL), other non-CLL lymphoproliferative disorders (OLPD) and viral diseases. The standard deviation of volume index (SDVI) is significantly higher in the three groups, whereas the mean volume index (MVI) is significantly lower in B-CLL, and increased in OLPD and viral diseases. These two groups could be distinguished by their mean conductivity index (MCI), which is significantly lower in viral disease group. Cut-offs were calculated for each parameter by the mean of Receiver Operating Characteristic (ROC) analysis. The study of the detection performances showed that the combination of lymphocyte count with SDVI, MVI and MCI could be used with a good sensitivity and specificity to discriminate between the most frequent lymphocyte pathologies, even in patients with normal lymphocyte count.

Automated detection of malaria by means of the haematology analyser CoulterR GEN.STM

The haematology analysers Coulter(R) GEN.S(TM) and LH(TM) give a set of data--'positional parameters'--which define each WBC population by mean of index values, the mean and the standard deviation (SD) of volume, conductivity and scatter, used to identify the WBC populations. These parameters were analysed in patients investigated for suspicion of malaria, in order to show a difference between malaria negative and malaria positive patients and to use it for malaria detection. The six parameters exhibiting a significant difference between the two groups were submitted to a ROC analysis, which showed both sensitivity >90% and specificity >60% for two parameters, lymphocyte and monocyte SDs of volumes. A discriminator combining the two parameters showed a sensitivity of 96.9% and a specificity of 82.5%. The cut off of the discriminative value was calculated. Because of the good stability and reproducibility of the parameters selected, the test can be used in order to detect patients having a high probability to be malaria positive and to pay particular attention to these blood smears. For more extensive diagnostic use, a standard control procedure of the positional parameters should be introduced.

Agranular CD4+/CD56+ cutaneous neoplasm

CD4+ CD56+ cutaneous neoplasm with hematological relapse is a rare malignant disease and has been described recently in the literature as blastic or agranular NK-cell leukemia/lymphoma. The origin of this neoplasm is uncertain. We describe a 75-year-old patient with a primary cutaneous neoplasm CD4+ CD56+ who evolved to leukemic phase despite standard lymphoma chemotherapy. Morphologically, the cells were undifferentiated without granules in the cytoplasm. The immunophenotype showed the expression of CD4, CD56, CD68, CD33, CD7, CD2, CD45RA, and CD38. Histological analysis revealed a cell infiltration mainly located in the dermis. T-cell receptor and immunoglobulin heavy chain genes were in germline configuration. Cytogenetic study showed complex structural abnormalities with a deletion of the chromosome 5 del(5q). The clinical course was aggressive with an early hematological relapse.

[Evaluation of the Beckman Coulter HmX hematology analyser at a general hospital]

The Beckman Coulter HmX is an hematological analyzer designed to provide a complete hematological profile including CBC, WBC differential (diff) and reticulocyte parameters. It has been evaluated in our laboratory over a two weeks period with three purposes: (1) a technical evaluation of the HmX performance, in regard to repeatability, linearity, carry over; (2) a comparison of numerical results (CBC, WBC diff) and analytical performance (flag sensitivity and specificity) with those obtained with the Coulter MaxM in use in our laboratory; (3) an analysis of the flagging algorithms using the blood smear as the reference method. The first part of the evaluation showed that the Beckman Coulter HmX is reproducible, and linear. The comparison between MaxM and HmX showed that the results given by the two instruments are similar and suggested that the Beckman Coulter HmX could replace the current hematology analyzer in use in our laboratory. The comparison of the flag system performance, between the Beckman Coulter HmX and the Coulter MaxM, has been performed with samples from three subgroups of patients (general departments, surgery and intensive care, hematological unit), and showed that the HmX is significantly more sensitive than the MaxM, with an higher global efficiency. The comparison of predictive values also showed a better performance of the HmX. In conclusion, the Beckman Coulter HmX is suited for an use in medium sized hospital laboratories (80 to 150 CBC diff/day), with good technical and analytical performance, a throughput of 75 samples/hr and a workstation allowing data management in accord with quality assurance guidelines in France.

Chronic lymphocytic leukemia associated with myelodysplastic syndrome and/or chronic myeloid leukemia: evidence for independent clonal chromosomal evolution

We describe the cytogenetic findings of three cases with simultaneous or sequential development of a B-chronic lymphocytic leukemia (B-CLL) and either a myelodysplastic syndrome (MDS) in 2 cases or a chronic myeloid leukemia (CML) in one case. The coexistence of these two hematologic malignancies leads to questions about their cell of origin. Through analysis of the cytogenetic abnormalities, we studied the derivation of both malignancies. The cytogenetic analyses of these three patients were simultaneously studied from both peripheral blood and bone marrow. Furthermore unstimulated short-time (USSTC) and long-time (72-96 hours) stimulated cultures (LTSC) were systematically performed. In all cases, we have demonstrated the independent bi-clonal evolution. This is the first report ever described for patients with CLPD and MDS and/or MPD shown to arise from distinct chromosomal abnormalities.

CD3+ CD8+ CD56- clonal large granular lymphocyte leukaemia and HIV infection

High-grade malignant lymphomas associated with HIV infection are usually derived from B lymphocytes. Although a broad spectrum of T-cell-derived malignancies has been described, no case of monoclonal T large granular lymphocyte leukaemia has been reported to date. We report a case of clonal T-LGL (CD3+, CD4-, CD8+, CD56-, CD57+) in an HIV-infected. HTLV1/2-negative individual. Large granular lymphocytes are thought to represent activated cytotoxic T lymphocytes. HIV infection, as previously reported for HTLV1/2, may represent a pathway of antigen activation and lead to clonal expansion of T large granular lymphocytes.

The 17p-syndrome: a distinct myelodysplastic syndrome entity?

The 17p- syndrome is a subset of myelodysplastic syndrome characterized by "typical" dysgranulopoïesis, combining a pseudo-Pelger-Hüet and a deletion of the short arm of chromosome 17. We describe two patients; one with de novo myelodysplastic syndrome (RAEB), one with secondary MDS (RAEB-T). Both showed a 17p- deletion resulting from tanslocations involving 17p associated with an additional complex cytogenetics, and both of them had a particular type of dysgranulopoiesis, combining pseudo-Pelger-Hüet anomaly.

[Prospective survey on adverse effects of radiopharmaceuticals]

In France, radiopharmaceuticals have been considered as drugs since 1992. Few adverse reactions with radiopharmaceuticals were described in the literature. Some authors have reported a rate of 1 to 6 reactions per 100,000 injections. The purpose of the present study was to evaluate the prevalence of radiopharmaceutical-induced side effects. A prospective survey was performed from November 1993 to May 1995 (during 18 months) in the Department of Nuclear Medicine of the University Hospital in Toulouse. There were 14,794 injections of radiopharmaceuticals (99mTc-phytate, 99mTc-microspheres of serum albumin, 99mTc-dimercapto-succinic acid (DMSA), 99mTc-hydroxymethyldiphosphonate (HMDP), 99Tc-colloid, 99mTc, 99mTc-sestamibi, Thallium-201). Three side effects were reported: one case of necrosis at the injection site, one case of vomiting and one case of dizziness. All the cases occurred with Tc99m-pyrophosphate. According to the WHO definition, the first side effect was classified as 'serious'. The causal relationship was unlikely for the first and second case and probable for the third. The outcome of these side effects was always favorable.

Lymphoproliferative disorders after organ transplantation: a report of 24 cases observed in a single center

PURPOSE

Organ recipients are at a high risk of post-transplant lymphoproliferative disorders (PTLDs) as a complication of immunosuppressive therapy. We report the incidence, clinical presentation, pathologic findings, treatment, and outcome for 24 cases of PTLD observed at our institution.

PATIENTS AND METHODS

Twenty-four (1.7%) of 1,385 organ transplant recipients developed PTLDs. Dosages of immunosuppressive drugs were reduced in 19 patients. Treatment consisted of anti-B-cell monoclonal antibodies (12 patients), and/or chemotherapy (eight patients), or surgery (two patients).

RESULTS

The median time between grafting and the onset of PTLD was 210 days. Tumors were classified as monomorphic and polymorphic in nine and 15 cases, respectively. Three of 24 cases were of T-cell origin. Genotypic studies confirmed the monoclonality of the tumors in 11 cases among 14 PTLDs tested. Epstein-Barr virus (EBV) infection was associated with 70% of B-cell PTLDs tested. The overall survival duration was 5 months. Ten patients are alive and disease-free with a median follow-up time of 37 months; most were treated with anti-B-cell antibodies. Two other patients died in complete remission of unrelated causes at 33 and 38 months.

CONCLUSION

Anti-B-cell monoclonal antibody therapy seems to be effective in PTLD, even in monoclonal B-cell forms, but other approaches will be necessary to improve survival further.

Bone marrow one step fixation-decalcification in Lowy FMA solution: an immunohistological and in situ hybridization study

The immunoreactivity of paraffin embedded bone marrow biopsies (BMB) was studied following a one step 20-hour-fixation-decalcification in Lowy formalin mercuric chlorid acid solution which permits excellent histological stainings. Antibodies reactive with myeloid, megakaryocytic, erythroid cells, T and B lymphocytes, mastocytes and metastatic cells were compared. Nearly all antibodies working on paraffin sections were demonstrated on Lowy FMA fixed BMB. Special care was taken to define an optimal working dilution. Trypsinization was not necessary. A slide microwave pre-treatment appeared essential before testing CD20 L26, CD8, CD3, CD34, MB1 Kappa and Lambda antibodies. It was suitable for UCHL1, LN2, CD30 antibodies. The same fixative allowed an m RNA Kappa or Lambda in myeloma and EBER 1 EBV RNAs in HIV lymphoma visualization by in situ hybridization. The safety handling of the toxic mercuric chloride component is discussed.

Recombination pattern of the TCR gamma locus in human peripheral T-cell lymphomas

The recombination events of the gamma and beta T-cell receptor (TCR) loci were analysed in a series of 39 peripheral T-cell lymphomas (PTCLs) in association with the expression of TCR chains. In TCR alpha beta PTCLs, 22/23 cases showed a gamma-gene rearrangement while only 18/23 showed a concomitant beta-gene rearrangement. The germline configuration of the beta locus was found in angiommunoblastic lymphadenopathy and lymphoepithelioid lymphomas. Three gamma delta PTCLs rearranged both gamma and beta genes. TCR silent PTCLs showed three different patterns of gamma- and beta-gene rearrangements. Three cases were in germline configuration for both loci; five cases had a rearranged gamma and a germline beta locus; and five cases had the two loci rearranged. Regarding the variable genes in the gamma-rearranged alleles, members of the V gamma I subgroup were the most frequently presented (39/50), followed by V gamma II, V gamma III, and V gamma IV (9/50, 1/50, and 1/50, respectively). Joining segment usage was as follows: J1 or J2 (32/50), JP1 or JP2 (17/50), and JP (1/50). Taken together, these data demonstrate that the gamma locus is more frequently rearranged whatever the TCR expression. The gamma-locus analysis provides a better diagnostic yield than the beta locus in the study of PTCL clonality.

Patterns of Epstein-Barr virus latent and replicative gene expression in Epstein-Barr virus B cell lymphoproliferative disorders after organ transplantation

B cell lymphoproliferative disorders arising in organ transplant recipients (B cell posttransplant lymphoproliferative disorders [PTLD]) are generally associated with EBV. In previous reports, B cell PTLD were shown to express the full pattern of EBV latent genes, as in vitro-established lymphoblastoid cell lines. Although viral linear DNA was detected in 40% of lymphoproliferative disorders from immunocompromised hosts, immunophenotypic studies failed to detect late EBV replicative antigens. The aim of this study was to investigate the relationship of EBV latent gene expression in B cell PTLD to morphology, clonality, and immunophenotype, and to examine the replicative state of EBV in malignant cells. For this purpose, 9 cases of EBV-related B cell PTLD were analyzed. Immunoglobulin gene rearrangements were detected by Southern blot analysis. The presence of EBV was assessed by Southern blot and by in situ hybridization. B cell differentiation antigens, adhesion and activation molecules, and EBV latent and replicative gene expression were studied using immunohistochemistry techniques. We demonstrated that EBV-related B cell PTLD exhibited varying patterns of latent viral gene expression. Higher levels of adhesion molecules were detected in latent membrane protein 1 (LMP1) or LMP1 plus EBV nuclear antigen 2 (EBNA2)-positive tumors than in LMP1 and EBNA2-negative tumors. In contrast, there was no relationship between CD21 and CD23 expression and latent EBV phenotype. Activation of the EBV replicative cycle was highlighted by BamHI Z left frame 1 expression in 5 of 9 cases. Less frequent expression of late viral proteins suggested that the initiation of the EBV lytic cycle might not always lead to virions production.

Visualization of the endogenous NF-kappa B p50 subunit in the nucleus of follicular dendritic cells in germinal centers

NF-kappa B, a 50 kDa/65 kDa (p50/p65) heterodimer, is a ubiquitous transcription factor involved in the positive regulation of various immune genes. The aim of this study was to determine whether NF-kappa B is related to a particular cell type and/or differentiation step during immunopoiesis. Using in situ hybridization on sections from non HIV hyperplastic lymph nodes, we found that the gene of the 105 kDa precursor of p50 was overexpressed in the light zone of germinal centers, with a network aspect, which suggested the involvement of follicular dendritic cells (FDC). By immunohistochemistry, p50 protein was detected in the cytoplasm and nucleus of FDC, confirming the involvement of FDC. Furthermore, p50 protein was detected in the cytoplasm of all lymphocytes. Thus, we focused our study on isolated FDC clusters from normal tonsils. As showed on tissue sections, we detected the p50 in both cytoplasm and nucleus of FDC. Nuclei of lymphocytes from FDC clusters were negative. We next studied p65 and c-Rel protein expression in FDC clusters. p65 was detected in the cytoplasm of FDC, whereas nuclei were negative. Furthermore, p65 was detected in the nuclei of some lymphocytes. c-Rel protein was detected only in the cytoplasm of lymphocytes and not in the nucleus and cytoplasm of FDC. Our results indicated that, in the context of T cell-dependent B cell immunopoiesis occurring in FDC clusters, p50 is mainly related to FDC with a massive overexpression in the nuclei, whereas p65 is expressed in a scattered manner in the nuclei of lymphocytes and c-Rel protein exclusively in the cytoplasm of lymphocytes from FDC clusters. These results suggested that the two subunits of NF-kappa B and the c-Rel protein have different roles in different cell types during B cell immunopoiesis.

CD23 and IgE expression during the human immune response to cutaneous leishmaniasis: possible role in monocyte activation

Leishmania brasiliensis causes cutaneous leishmaniasis (CL) in humans. During this infection, a variety of inflammatory mediators are produced by T cells and monocytes/macrophages. In the present study, we analysed serum IgE levels and their correlation with in situ expression of the low affinity receptor for IgE (Fc epsilon RII/CD23) in patients infected with L. brasiliensis before and following therapy. These analyses were compared to in situ expression of tumour necrosis factor-alpha (TNF alpha), interleukin 3 (IL3), interferon-gamma (IFN gamma) and IL4. Disease-free individuals from the same endemic area sensitized with L. brasiliensis antigens were also included in this work. Our data indicate that during infection, serum levels of IgE and TNF alpha increased and correlated with elevated in situ expression of CD23, IL4 and TNF alpha mRNA. This expression disappeared following successful treatment, but persisted in patients resistant to anti-leishmania therapy. Patients resistant to therapy differed from other cases by a dramatic decrease in their in vivo expression of IFN gamma protein. Analysis of CD23 function in purified human monocytes indicated that this antigen mediates IgE/anti-IgE-dependent TNF alpha production. These data suggest a possible in vivo role of CD23 in acute immune responses in human CL.

Visualization of the endogenous NF-kappa B p50 subunit in the nucleus of follicular dendritic cells in germinal centers

NF-kappa B, a 50 kDa/65 kDa (p50/p65) heterodimer, is a ubiquitous transcription factor involved in the positive regulation of various immune genes. The aim of this study was to determine whether NF-kappa B is related to a particular cell type and/or differentiation step during immunopoiesis. Using in situ hybridization on sections from non HIV hyperplastic lymph nodes, we found that the gene of the 105 kDa precursor of p50 was overexpressed in the light zone of germinal centers, with a network aspect, which suggested the involvement of follicular dendritic cells (FDC). By immunohistochemistry, p50 protein was detected in the cytoplasm and nucleus of FDC, confirming the involvement of FDC. Furthermore, p50 protein was detected in the cytoplasm of all lymphocytes. Thus, we focused our study on isolated FDC clusters from normal tonsils. As showed on tissue sections, we detected the p50 in both cytoplasm and nucleus of FDC. Nuclei of lymphocytes from FDC clusters were negative. We next studied p65 and c-Rel protein expression in FDC clusters. p65 was detected in the cytoplasm of FDC, whereas nuclei were negative. Furthermore, p65 was detected in the nuclei of some lymphocytes. c-Rel protein was detected only in the cytoplasm of lymphocytes and not in the nucleus and cytoplasm of FDC. Our results indicated that, in the context of T cell-dependent B cell immunopoiesis occurring in FDC clusters, p50 is mainly related to FDC with a massive overexpression in the nuclei, whereas p65 is expressed in a scattered manner in the nuclei of lymphocytes and c-Rel protein exclusively in the cytoplasm of lymphocytes from FDC clusters. These results suggested that the two subunits of NF-kappa B and the c-Rel protein have different roles in different cell types during B cell immunopoiesis.

Adult T-cell leukemia/lymphoma revealed by a surgically cured cardiac valve lymphomatous involvement in an Iranian woman: clinical, immunopathological and viromolecular studies

A 60-year-old woman from the town of Mashhad in northeastern Iran developed cardiac failure due to aortic and mitral regurgitations which needed cardiac valve replacement. Histopathological study of the valves revealed a T-cell non-Hodgkin's lymphoma. Blood examination showed leukemic features with 32% of abnormal white blood cells. Human T-cell leukemia/lymphoma virus type I (HTLV-I) antibodies were present in the serum and the specific env HTLV-I sequences were detected in the DNA extracted from the valves and peripheral blood mononuclear cells (PBMC) using polymerase chain reaction technique. Clonal integration of two HTLV-I copies was found in both the valves and PBMC DNA, thus the diagnosis of adult T-cell leukemia/lymphoma (ATL) was established. In contrast to the acute life-threatening cardiac localization, our case met the diagnostic criteria of chronic ATL, this was confirmed by favorable evolution without chemotherapy during the 24 months after diagnosis. According to our knowledge, this is the first report of an isolated lymphomatous cardiac valve involvement, without other cardiac abnormalities. It seems important to underline that the patient originated from Iran where endemicity of HTLV-I has only recently been discovered.

Expression of CD23 by human bone marrow stromal cells

CD23 is a surface antigen expressed by a variety of human hematopoietic cells and shown to display multiple biological functions. In present work, we assayed CD23 expression by human bone marrow (BM) or by stromal cells derived from this tissue. While freshly isolated BM-cells showed low CD23 expression, a subset of long term BM-culture (LTBMC)-derived stromal cells expressed CD23 mRNA at high levels in their steady state and secreted soluble CD23 in their culture supernatants. To assay the role of CD23 in LTBMC, these cultures were initiated in the presence of neutralizing anti-CD23 mAb. A dramatic decrease in total numbers of hematopoietic cells and CFU-GM recovery was observed in these cultures as compared to controls. These data suggest a role of CD23 expression in stroma cell functions and further confirm the ability of this antigen to regulate human hematopoietic cell development.

Epidermal keratinocyte-derived basophil promoting activity. Role of interleukin 3 and soluble CD23

Human epidermal keratinocytes (EK) secrete factors able to sustain the proliferation of early myeloid cells and, in particular, the generation of basophils. This activity was previously attributed to IL-3, although no definitive in situ demonstration of this cytokine was provided. In regard to the possible physiological relevance of these data, we investigated herein the nature of EK-derived factors responsible for basophil promotion. Our data show that EK-derived supernatants (EK-sup) contain IL-3 as well as soluble CD23 (sCD23), both known for their colony stimulating activity. Messenger RNA for IL-3 and CD23 were also detected in EK. Blocking experiments using specific neutralizing monoclonal antibodies (mAb) further indicate that EK-derived basophil promoting activity is mainly due to the presence of IL-3 and sCD23 in EK-sup. Furthermore, by contrast to IL-3, sCD23 secretion by EK is cortisone sensitive and highly enhanced by IL-4, suggesting distinct regulatory mechanisms for their production.

Interleukin-7 is a growth factor for Sézary lymphoma cells

Sézary syndrome is a cutaneous T cell lymphoma characterized by infiltration of the skin by CD4+ cells. These cells generally respond poorly to mitogens and T cell activators. We have studied the action of IL1 to IL4, IL6, and IL7 on the proliferation of Sézary cells from 12 patients. With the exception of IL2 and IL7, the cytokines studied had no proliferative effect on these cells. Whereas IL2 had only a low proliferative capacity (two- to threefold increase) on peripheral blood mononuclear cells, recombinant IL7 constantly induced a very significant (3-40-fold increase) proliferative response, and was used successfully to generate cell lines in three out of eight cases. Growth of Sézary cell lines was shown to be strictly dependent on IL7, and after 2-5 wk of culture presented a switch to a homogeneous phenotype CD3+4+8-7- (except for one line that remained CD7+), with a typical morphology of Sézary cells. Their tumoral origin was demonstrated by the expression of the same T cell receptor-beta gene rearrangement as the patients' T cells. Importantly, cultured normal epidermal keratinocyte supernatants could support the growth of our Sézary lines. Furthermore, the proliferative activity contained in these supernatants was completely blocked by a monoclonal anti-IL7 antibody. These results suggest that IL7 may, therefore, represent an important cytokine in the physiopathology of cutaneous T cell lymphoma.

Thymic epithelial cell-derived supernatants sustain the maturation of human prothymocytes: involvement of interleukin 1 and CD23

During their development, human CD7+ lymphoid stem cells migrate into the thymus where, following intimate contact with thymic tissue, they proliferate and differentiate into functionally mature T lymphocytes. In this study, we investigated the effect of thymic epithelial cell-derived supernatants (TEC-SN) on early CD7+CD2-CD3- thymocytes. Our results indicate that TEC-SN are able to promote CD2 and CD3/TcR alpha/beta expression by CD7+ precursors. This activity correlated with soluble CD23 and interleukin 1 levels in TEC-SN. Furthermore, monoclonal antibodies to these cytokines decreased in vitro maturation of prothymocytes. Thus, in addition to cell-cell interactions, human TEC produce cytokines able to support early steps of thymocyte differentiation.

Synergistic effect of interleukin 1 and soluble CD23 on the growth of human CD4+ bone marrow-derived T cells

Low-affinity Fc epsilon receptor (Fc epsilon RII/CD23) is expressed by various human cells and known to be cleaved into soluble fragments (sCD23). Several biological activities were ascribed to these molecules. In this study, we have assessed the effect of recombinant 25-kDa sCD23 (rsCD23) on human bone marrow-derived T cells. Our results show that rsCD23 in synergy with recombinant interleukin 1 enhances mitogenic responsiveness of CD4+ T cells but does not affect CD8+ cell growth. Furthermore, rsCD23 synergizes autologous marrow cells in enhancement of CD4+ cell growth while CD23 monoclonal antibodies decrease accessory cell effect. Together, these data confirm cytokine-like activity of sCD23 on human T cell lineage.

Human thymic epithelial cells produce interleukin-3

Interleukin-3 (IL-3) is a hematopoietic growth factor suggested to be produced by activated T lymphocytes. Meanwhile, supernatants from human thymic stroma could promote the proliferation of myeloid stem cells. Thus, we investigated whether IL-3 accounts for this activity. Therefore, human thymic epithelial cells (TEC), fibroblasts, and adherent cells were isolated, and their culture supernatants assayed for myeloid colony promotion. Only supernatants from thymic epithelial cells supported colony-forming unit growth in semisolid media. This effect decreased following anti-IL-3 monoclonal antibody addition to these cultures. Furthermore, in situ hybridization showed the presence of IL-3 mRNA in epithelial cells. Effect of TEC culture conditions on IL-3 production by these cells was also studied. Together, these data show that IL-3 production is not the exclusive property of human activated T lymphocytes.

[Transrectal ultrasonography of the prostate (author's transl)]

A French instrumentation for transrectal ultrasonography of the prostate by means of a rectal probe containing a rotative transducer is presented. Typical ultrasonographic images are shown. Accurate information on the size of the gland is obtained by this method and adenomas can easily be distinguished from adenocarcinomas. The method might eventually be of considerable value for the screening of asymptomatic subjects and early detection of prostatic cancer.