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Onychomatricoma (OM) is a tumor of the nail matrix typified histologically by multiple distal fibroepithelial projections and a thick keratogenous zone forming multiple V-shaped invaginations at the level of epithelial ridges, with the formation of a thick nail plate. In its proximal portion, the thickness of the nail looks like a spur originating from the ventral part of the nail plate. In its distal part, beyond the lunula, the nail plate is globally thickened and filled with cavities containing serous fluid. Often, however, the pathologist is not provided with the nail plate. The diagnosis then rests on the presence of a fibroepithelial tumor. In this article the histologic criteria of OM without nail plate are refined and OM is characterized immunohistochemically using three tumors fixed in liquid nitrogen and examined separately from the nail plate. On longitudinal section OM without nail plate appears as a unique pedunculated fibroepithelial tumor i.e., the multiple distal epithelial digitations arranged along a transversal plane are not seen. The feature is reminiscent of fibrokeratoma. When OM is visualized in longitudinal section, 3 main criteria differentiate OM from fibrokeratoma: the presence of epithelial-lined invaginations around optical cavities, a stroma organized in 2 layers, and the absence of horny corn. Patterns of expression of cytokeratins and integrins in OM are identical to that observed in the normal nail matrix. Involucrin finds expression from the basal layer through to the top of the epithelium, where it is more marked and where transglutaminase 1 is restricted. Merkel cells detected by CK 20 are increased in number and sometimes disposed in clusters. The fibrous component of OM is composed of 2 layers: a superficial stroma made of numerous fines fibrils of collagen IV intermingled with collagen I, and deep stroma made principally of collagen I. Antibody AE13, specific to trichocytic keratins Ha 1-4, represent a good potential marker of OM. Its V-shaped expression in epithelium ridges offers early identification of the keratogenous zone of OM, on tumors separated from their nail plates and limited to their fibroepithelial components.

To perform a descriptive analysis of patients with chronic hepatitis C based on a local registry of liver biopsies.Collection of clinical, biological and histological data from all HCV-infected patients who underwent liver biopsy between January 1997 and December 1998 in the Alpes-Maritimes (France).One thousand and fifty six patients including 924 who lived in the Alpes-Maritimes (515 male, 409 female, mean age: 44.9 years old) were included. Intravenous drug use (30.1%) was the major suspected source of infection before blood transfusion (28.2%). Among intravenous drug users, 38% of patients were infected with genotype 1a and 37.4% with genotype 3. The METAVIR fibrosis severity score was distributed as follows: F0: 10.8%, F1: 53.7%, F2: 15.9%, F3: 14.7%, and F4: 4.9%. In a multivariate analysis adjusted for the duration of infection, independent risk factors associated with the severity of fibrosis were age at contamination=30 years, genotype other than 1a and alcohol intake=50 g/day. Determination of HCV antibody and liver biopsy were performed an average of 12.5 and 14 years after presumed date of contamination, respectively.These data provide a clearer view of the impact of this condition in this area and could help to define a comprehensive policy for patient management.

In vitro, LSLCL is expressed by numerous myeloid, promyelocytic, and T or B lymphoblastoid cell lines. In vivo, LSLCL is strongly expressed in bone marrow and only faintly in lymphoid organs. We show here that, in bone marrow, LSLCL is detected: (i) concentrated in the cytoplasm of immature neutrophils but not in myeloblasts nor in mature neutrophils, (ii) in extracellular bone marrow fluid. Besides, numerous cDNAs, similar to LSLCL (identity of 93–99 %), are found in ‘expressed sequence tags’ databases from various origins, mostly fetal and undifferentiated tumour tissues. Since LSLCL and various closely related cDNAs are expressed at definite stages of cellular maturation processes, we hypothesize that this class of proteins could play an important role in the control of cellular differentiation.

Contexte L’INCa et la SFP ont publie en 2011 une mise a jour du document « Comptes rendus (CR) d’anatomopathologie : donnees minimales a renseigner pour une tumeur primitive ». Les evolutions par rapport a la version de 2009 concernaient aussi bien les donnees medicales qu’administratives. Objectif Realiser un bilan du renseignement de 14 donnees administratives concernant l’identification du patient, des praticiens et des structures en charge du dossier, et des elements de tracabilite. Methodologie Les evaluations des CR ont ete declaratives et anonymes. Elles ont porte en 2012 sur 10 CR recents et consecutifs pour cancer du corps uterin, du sein, du testicule, des tissus mous, de melanome, emanant respectivement de 23, 34, 12, 6 et 17 structures, soit 920 CR. En 2013, l’evaluation a porte sur 10 CR pour cancer du colon, du poumon, de la prostate, du rein, de la thyroide, emanant respectivement de 21, 13, 18, 12 et 17 structures, soit 810 CR et un total de 1730 CR sur les 2 dernieres annees. En raison des modalites d’anonymat, il n’a pas ete possible d’identifier les structures ayant participe a plusieurs evaluations. Resultats Pour 7 criteres, le taux de non-conformites (NConf) etait * ) du patient (95,8 % de NConf dont 55,5 % de NCom), identifiant permanent de sante (IPP * ) attribue par l’etablissement au patient (66,3 % de NConf dont 25,4 % de NCom), code postal * de residence du patient (62,1 % de NConf dont 25,3 % de NCom), numero FINESS * de l’etablissement d’origine du prelevement (91,2 % de NConf dont 57,1 % de NCom, quand applicable), date de prelevement (29,4 % de NConf dont 3,7 % de NCom), numero FINESS * de la structure ACP (86,0 % de NConf). Quatre criteres etaient « non-communiques par le preleveur » dans plus de 10 % des cas (INS du patient, IPP attribue par l’etablissement au patient, code postal de residence du patient et numero FINESS de l’etablissement d’origine du prelevement). Conclusion Les donnees administratives recemment requises sont insuffisamment renseignees dans la plupart des CR ACP. Pallier ce manque demande a etre sensibilise au sujet, de faire evoluer les feuilles de prescription et de mettre a jour les systemes informatiques. * Donnees requises depuis 2011.

The interstitial granulomatous drug reaction (IGDR) is a novel drug-associated entity, characterized by violaceous plaques with a predilection for skin fold areas. Light microscopically, it resembles the incipient diffuse interstitial phase of granuloma annulare. Differentiating light microscopic features include the absence of complete collagen necrobiosis, the presence of interface dermatitis, and variable lymphoid atypia. The lack of vasculitis rules out the extravascular necrotizing granuloma (Winkelmann granuloma) associated with systemic disease. The differential diagnosis with interstitial granulomatous dermatitis with arthritis as defined by Ackerman et al. has not been studied until now. Our aim was to determine the histologic criteria allowing us to differentiate IGDR without interface dermatitis and lymphoid atypia from interstitial granulomatous dermatitis. We report three patients with IGDR triggered, in two cases by respectively angiotensin convertin enzyme (ACE) inhibitors and furosemide, and in one case by the association of an ACE inhibitor, furosemide, and fluindione. Histologic examination showed a histological pattern of interstitial granulomatous dermatitis. We found a dense, diffuse histiocytic infiltrate distributed interstitially and in palisaded array within the reticular dermis. Eosinophils and some neutrophils were scattered throughout the infiltrate. In some tiny foci, enveloped by histiocytes, thick collagen bundles associated with basophilic nuclear debris or "flame figures" were seen. Vasculitis, interface dermatitis, or lymphoid atypia were absent. Our study allowed us to expand the histological spectrum of IGDR including a histological pattern similar to interstitial granulomatous dermatitis. The lack of degenerated collagen could be a subtle clue in favor of interstitial granulomatous dermatitis triggered by a drug.

A 37-year-old woman underwent resection of an abdominal tumour which was adherent to the wall of the ileum. The diagnosis of an ependymoma was supported by evidence of typical perivascular pseudorosettes which stained positive for glial fibrillary acidic protein and contained abundant intermediate filaments within the elongated processes by electron microscopy. Flow cytometric study showed a diploid population of tumour cells. This is the first case of an ependymoma arising from the small bowel without any connection to the genital tract, the omentum or with the sacroccygeal area. As is the case with other unusual and ectopic localisations of ependymomas, prognosis of this tumour is difficult to evaluate.

Resume Les auteurs rapportent un cas d'actinomycose abdominopelvienne, infection bacterienne rare. Son expression clinique tumorale avec fistulisation a la peau et son diagnostic rapide par ponction-biopsie sous echographie en font une observation exceptionnelle. A propos de ce cas, les aspects clinique, bacteriologique, histologique et therapeutique de l'actinomycose sont etudies.

Summary The ultrastructure of polymorphonuclear leucocytes (PMNL) was studied in 16 patients infected with the human immunodeficiency virus (HIV). PMNL were isolated from HIV-infected patients with CD4+ lymphocytes counts >200/mm 3 (without signs of active infection)( n = 12)(group 1), or 3 ( n = 4)(group 2), and from 16 healthy volunteers (group 3). Immunoelectron microscopy staining using an anti-β2 integrin antibody (anti-CD18) was performed on PMNL from three individuals of group 2 and of three individuals of group 3, before and after incubation with N -formyl-methionyl-leucyl-phenylalanine (f-MLP). The radical oxygen intermediates (ROI) production of PMNL was investigated by luminolmediated chemiluminescence. A number of ultrastructural abnormalities in PMNL were found in a higher proportion in HIV-infected patients. These were: (a) an increase in the size of the Golgi apparatus and in the number of mitochondria, and in the quantity of endoplasmic reticulum; (b) some dysplastic features including large cytoplamic vacuoles, whorl of myelin, and nuclear pockets; (c) an increase prevalence of multivesicular bodies compared with control PMNL; (d) some cylindrical confronting cisternae and tubu-loreticular structures. After anti-CD18 staining, gold particles were seen on the plasma membrane and more rarely inside the cytoplasm of PMNL from each group but no decrease in this staining was noted in HIV PMNL. Incubation with f-MLP similarly increased the immunostaining of the PMNL in each group. In vitro ROI production was significantly depressed for HIV PMNL compared with control PMNL. Some ultra-structural abnormalities observed in this study could support the possibility that one of the mechanisms underlying the qualitative functional defects of PMNL from HIV-infected patients may be related to some cytopathic effect.

Necropsy findings in 395 adult patients with the acquired immunodeficiency syndrome (AIDS) who died in Nice, France, between March 1983 and May 1996 were compared retrospectively with antemortem diagnoses, risk factors and number of positive T CD4 lymphocytes at the time of death. Special emphasis on bacterial infections was made in this study. Lesions observed from 1983 through 1989 and from 1990 through 1996 were compared. We assessed the role of organ lesions in the immediate cause of death. The organ system distribution of major opportunistic infections and neoplasms was similar throughout the years of the study. The most common diagnostic disease entities in all organ sites were cytomegalovirus infection, toxoplasmosis and candidiasis. Toxoplasmosis was more common in the intravenous drug abuser group. Bacterial infections were frequent and contributed to the mortality and morbidity of all risk factor groups. Kaposi' sarcoma continued to occur more frequently in the homosexual population. Cytomegalovirus infection remained one of the most common causes of death from 1983 to 1996. Mortality from fungal and bacterial infections, and mycobacteriosis increased in frequency during the course of this study whereas deaths from pneumocystosis declined. The death rate from malignant lymphoma and carcinoma increased after 1989. The clinical cause of death concurred with the pathological cause in 55% of the cases. Lung was the most frequent organ involved followed by the central nervous system the gastrointestinal tract and the heart.

Supernumerary ring or giant rod marker chromosomes are a characteristic of well-differentiated liposarcomas (WDLPS) and atypical lipomas (ALP) and are often observed as the sole cytogenetic abnormality, but are rare in lipomas. Using a combination of different methods, we extensively investigated the structure and composition of rings and giant rods in a series of 17 WDLPS-ALP samples and three intra- or intermuscular lipomas (IMLP), revealing a unique combination of particular features strikingly related to these tumors. Although the rings and rods displayed in vitro and in vivo stability, the presence of alpha-satellites could not be detected on these supernumerary structures. Comparative genomic hybridization analysis, in combination with fluorescence in situ hybridization, identified the chromosomal regions contributing to the formation of these chromosomes: in WDLPS-ALP, all carried amplifications of 12q 14-15 and the MDM2 gene, with variable other noncontiguous regions. In the three IMLP, the rings consistently carried amplifications of 12q15-21 and 1q21, but increased copies of MDM2 were found in only one case. Other genes located more proximal in 12q14-15 were amplified in several WDLPS-ALP, but showed a normal copy number in IMLP. Furthermore, the immunohistochemical expression of the MDM2 protein was detected in most (12/14) WDLPS-ALP, in 1-30% of the cells, but never in IMLP. These supernumerary chromosomes represent a peculiar kind of amplification structure, midway between double minute chromosomes and homogeneously staining regions, but the mechanisms underlying the formation of these structures remain obscure.

SP220K is a newly described serine proteinase which displays guanidinobenzoatase activity in its inactive form and gelatinolytic activity in its active form. SP220K expression was studied in 20 renal clear-cell carcinomas and in a series of renal oncocytomas, a rare benign tumor derived from the kidney tubule epithelium. We provide evidence that SP220K expression, as assessed by guanidinobenzoatase activity, gelatin zymography and Western blot immunodetection, was increased markedly in cancer basolateral membranes compared to kidney cortex controls, whereas no signal was detectable in basolateral membranes from the 5 renal oncocytomas studied. Cytoplasms of carcinoma cells were immunodetected consistently, whereas no expression was seen in oncocytic cells from any of the oncocytomas studied (12/12). Endothelial cells were immunodetected in all 3 tissue types. Our data favor a potential mechanistic relationship between expression of the matrix proteinase SP220K and invasive phenotype in kidney epithelium proliferative processes.

Liver biopsy (LB) has been advocated for the detection of mycobacterial infections in patients infected with human immunodeficiency virus (HIV). To determine the effect of the use of this procedure on survival, we compared it terms of yield with histological findings and noninvasive microbiological procedures. We reviewed the cases of 98 patients who underwent 106 LBs as part of the diagnostic screening for fever of unknown origin. LB revealed 17 cases of mycobacterial infection. For all but one patient, the results of at least one noninvasive procedure were positive. In 85 cases where infections were not diagnosed by LB, 17 had infections documented by other procedures. When all culture results are considered, the mean (+/- SD) incubation time to the first positive culture was 15 +/- 5 days, whereas the mean (+/- SD) incubation time to the first positive culture of an LB specimen was 28 +/- 9 days. The survival time was not significantly increased for patients who underwent LB and had positive Ziehl-Neelsen-stained smears; these patients survived a mean (+/- SD) of 12 +/- 11 months, whereas patients with negative smears survived a mean (+/- SD) of 9 +/- 10 months. Noninvasive studies are preferable to LB for the diagnosis of mycobacterial infections in HIV-infected patients.

Objective: To investigate the relationship between human immunodeficiency virus (HIV) and cervical intra-epithelial neoplasia (CIN). Design: A prospective study to determine the prevalence of cervical intra-epithelial neoplasia in 111 HIV-positive women. Methods: In total, 111 HIV + women were enrolled and underwent cervical biopsy and CD4 T-lymphocyte determination. Of the 111 women, 26 (23.4%) had CIN and another 26 (23.4%) had histologic evidence of cervicitis. Results: No significant difference was found between transmission group, CDC stage of disease, CD4 T-lymphocyte count and pregnancy. There was a significant association with concomitant human papillomavirus (HPV) infection ( P Conclusion: Public health measures are needed to provide Papanicolaou smear screening and appropriate clinical follow-up and treatment of women infected with the human immunodeficiency virus.

Resume Introduction Les causes de nodules pulmonaires multiples chez le patient infecte par le VIH sont d’abord infectieuses puis tumorales, en particulier le sarcome de Kaposi et les lymphomes. Observation Un homme de 40 ans, infecte par le VIH depuis 16 ans avec bilan viro-immunologique satisfaisant, etait hospitalise pour nodules pulmonaires bilateraux et une masse lytique costo-vertebrale dorsale. Les biopsies costales et pleurales montraient un hemangioendotheliome epithelioide malin. Discussion L’hemangioendotheliome epithelioide est une tumeur vasculaire rare, de bas grade de malignite. Nous rapportons le premier cas decrit chez un patient infecte par le VIH. L’atteinte pulmonaire sous forme de nodules bilateraux est classique mais non specifique. Une telle presentation chez un patient VIH pose le probleme de nombreux diagnostics differentiels et doit etre interpretee en fonction du statut immunitaire. Conclusion En cas de nodules pulmonaires chez un patient infecte par le VIH avec statut immunitaire conserve, les etiologies tumorales sont relativement frequentes. Avec l’allongement de la duree de vie de ces patients, ces etiologies se rapprochent de celles des sujets non infectes.

Background Testicular germ cell tumours are the most frequent cancer of young men with an increasing incidence all over the world. Pathogenesis and reasons of this increase remain unknown but epidemiological and clinical data have suggested that fetal exposure to environmental endocrine disruptors (EEDs) with estrogenic effects, could participate to testicular germ cell carcinogenesis. However, these EEDs (like bisphenol A) are often weak ligands for classical nuclear estrogen receptors. Several research groups recently showed that the non classical membrane G-protein coupled estrogen receptor (GPER/GPR30) mediates the effects of estrogens and several xenoestrogens through rapid non genomic activation of signal transduction pathways in various human estrogen dependent cancer cells (breast, ovary, endometrium). The aim of this study was to demonstrate that GPER was overexpressed in testicular tumours and was able to trigger JKT-1 seminoma cell proliferation. Results We report here for the first time a complete morphological and functional characterization of GPER in normal and malignant human testicular germ cells. In normal adult human testes, GPER was expressed by somatic (Sertoli cells) and germ cells (spermatogonia and spermatocytes). GPER was exclusively overexpressed in seminomas, the most frequent testicular germ cell cancer, localized at the cell membrane and triggered a proliferative effect on JKT-1 cells in vitro, which was completely abolished by G15 (a GPER selective antagonist) and by siRNA invalidation. Conclusion These results demonstrate that GPER is expressed by human normal adult testicular germ cells, specifically overexpressed in seminoma tumours and able to trigger seminoma cell proliferation in vitro. It should therefore be considered rather than classical ERs when xeno-estrogens or other endocrine disruptors are assessed in testicular germ cell cancers. It may also represent a prognosis marker and/or a therapeutic target for seminomas.

In the Mediterranean basin area, visceral leishmaniasis is an endemic disease caused by Leishnninia donovant infantum. This study describes the clinical and pathological features of one patient with AIDS who had oral (tonsillar) leishmaniasis, caused by a viscerotropic zymodcme, concurrent with a Kaposi's sarcoma and with a CMV infection.

Bacillary angiomatosis (BA) is a new clinicopathological entity defined as a pseudo-neoplastic capillary proliferation secondary to an opportunistic infection by one of two Rochalimaea sp.: R. quintana or R. henselae. Although BA is a recently recognised entity, numerous cases have been reported. Most of the patients affected are reported to have low absolute CD4 lymphocyte counts associated with AIDS. Yet, very few oral cases associated or not with cutaneous lesions have been reported or simply identified. Histopathological and ultrastructural features of one case of oral BA with gingival and palatal lesions are presented. Clinical aspects of oral BA do not hold pathognomonic features and the lesions may resemble either a reactive lesion of the gingiva, pyogenic granuloma or Kaposi's sarcoma. The lesion is characteristically composed of circumscribed lobular capillary proliferations and the presence of granular amphophilic material on haematoxylin and eosin sections surrounded by neutrophils and neutrophilic debris is a clue to diagnosis. Demonstration of bacilli in the interstitium by the Warthin-Starry silver method or, better, by electron microscopy is diagnostic. BA may contribute to the death of the patient but erythromycin has proved to be very effective treatment.

We report two patients with AIDS who had cutaneous spindle-cell pseudotumors caused by Leishmania infantum in one instance and by an atypical mycobacterium in the other. The lesions mimicked neoplasms with predominantly spindled macrophages, similar to those seen in the histoid variant of leprosy. This histoid reaction is known to be related to mycobacteria. To our knowledge, this is the first case of histoid reaction due to leishmania. In both cases, the histiocytic cells were positive for vimentin and desmin but negative for alpha-smooth muscle. In addition, the immunostaining by lysosyme and alpha 1 antitrypsin was positive in both and in one the S-100 protein was positive. This reaction suggests dual myofibroblast and histiocytic differentiation.

A case study of sinus histiocytosis of Rosai-Dorfman (SH) clinically limited to the skin is presented with immunohistochemical study of the infiltrate, in both paraffin and cryostal sections. Factor XIIIa, a dendrocyte marker, was demonstrated in the cytoplasm of histiocytes. This feature had not been previously reported in this disease. In addition, the cells expressed S100 protein, CD4, CD la, GD68, and GD11c. This immunophenotyping study suggests that SH could affect the antigen-presenting activity of Factor XIIIa cells, i.e., the skin dermal dendrocyte.

A case of primary intraocular malignant lymphoma without cerebral involvement is reported in a 30-year-old man with acquired immunodeficiency syndrome. The study of the enucleation specimen showed a B immunoblastic lymphoma with a CD30 positive anaplastic large cell component. There was no involvement of the adnexal structures of the orbit. The patient subsequently completed non-surgical staging showing no extension of the tumour. The clinical course was rapidly fatal with dissemination to the pericardium and pleura.

To the Editors: From July 1985 through August 1990, 320 cases of non-Hodgkin lymphoma were registered by the central anatomopathology laboratory of the University Hospitals of Nice. Among the 156 p...

17078 Background: The aim of this cohort study was to produce descriptive epidemiological data from the Group of Neuro- Oncology of Nice (GNON) database. Data were collected from the Comprehensive Cancer Center and the University Hospital of Nice (France). Methods: All cases that have been discussed during multidisciplinary meetings of neuro-oncology were entered. Data were compared with the Central Brain Tumor Registry of the United States (CBTRUS) report taken as reference tool. Follow-up information was obtained from the patient medical chart and from the national death registry. Results: 1,395 patients (718 males, 677 females) were registered in the data base. There were 938 tumors of neuroepithelial tissue (percentage of all reported cases in our study: 67.9%, median age in our study; 58 yrs, percentage in CBTRUS report: 43.6%, median age in CBTRUS report: 53 yrs), 55 tumors of cranial and spinal nerves (4.0%, 53 yrs; 8%, 52 yrs), 270 tumors of meninges (19.5%, 59 yrs; 31.4%, 63 yrs), 54 lymphoma and hemopoietic neoplasm (3.9%, 68 yrs; 3.1%, 60 yrs), 16 germ cell tumors, cysts and heterotopias (1.2%, 17yrs; 0.6%, 16yrs), 12 craniopharyngioma (0.9%, 50 yrs; 0.7%, 48 yrs), 9 chordoma/chondrosarcoma (0.6%, 65 yrs; 0.2%, 48 yrs), 27 unclassified tumors (2.0%, 46 yrs; 6.1%, 68 yrs). The table shows the survival rates at one, three and five years respectively for some selected brain and central nervous system tumors (results from the CBTRUS report in parentheses). Conclusions: A comparison between results from the CBTRUS and GNON data base showed some similarities and didn't point out any major unexplainable discrepancy. [Table: see text] No significant financial relationships to disclose.

The Bcr-Abl inhibitor imatinib is now the first line therapy for all newly diagnosed CML patients in chronic phase. Nevertheless resistance to the drug emerges as CML progresses to an acute deadly phase. Additional cellular targets should thus be identified to develop alternative therapeutic strategies. The transcription factor NF-kB is a pro-survival factor, found abnormally active in numerous hematologic malignancies. In the present study we show that the constitutive and abnormal activation of NF-kB in Bcr-Abl transformed BaF3 cells and in the LAMA84 CML line could be downregulated after inhibition of Bcr-Abl. Pharmacological blockade of NF-kB by the IKK2 inhibitor AS602868 (Serono International S.A.) prevented proliferation of BaF3/Bcr-Abl, LAMA84 and primary CML cells. Importantly, AS602868 led to apoptosis of an imatinib resistant variant of LAMA84 and of BaF3 clones expressing mutated form of Bcr-Abl derived from imatinib resistant patients. Moreover, NF-kB inhibition affected proliferation and hematopoietic colony formation of primary imatinib resistant CML cells. Finally, the IKK2 inhibitor prolonged survival of mice intravenously injected with the imatinib resistant clone LAMA84-r. Our data strongly suggest that NF-kB mediates important survival functions in CML cells for bcr-abl and that targeting NF-kB with the IKK2 inhibitor AS602868 may represent a new promising therapeutic strategy for CML treatment.

Les myiases cutanees humaines representent une pathologie frequente en region d’endemie tropicale. Les voyages organises de plus en plus nombreux sous les tropiques augmentent le nombre de cas importes. Nous rapportons un cas de myiase furonculoide a Dermatobia hominis (D.H) contracte au cours d’un sejour en Guyane francaise. Il importe, dans un premier temps, d’identifier les caracteristiques morphologiques communes des arthropodes qui sont la presence d’une cavite caelomique, d’un appareil respiratoire et circulatoire et d’une musculature striee. La demarche diagnostique doit etre ensuite eclairee de renseignements cliniques et epidemiologiques (notion d’un sejour en zone tropicale, de contage, localisation de la lesion au niveau des teguments). Le dernier probleme consiste a identifier les caracteristiques propres a D.H qui sont l’absence totale d’appendices locomoteurs, l’aspect bien arrondi des deux extremites, et, avec sur le segment anterieur, des crochets. Le diagnostique differentiel se pose avec les vers ou helminthes qui possedent une musculature lisse et n’ont aucun appareil respiratoire ou circulatoire ni cavite caelomique et avec un autre parasite, arthropode des teguments, qui est la puce-chique encore denommee Tunga penetrans. L’extraction et l’analyse d’une larve complete, comme dans notre observation, facilitent le diagnostic histologique. Cette pathologie est importante a connaitre car l’exerese de la larve permet la guerison.

Le carcinome neuroendocrine cutane primitif (a cellules de Merckel) (CNEP) peut de facon peu frequente etre associe a une tumeur differente (basocellulaire, kyste epidermique, naevus congenital geant) : tumeur de collision ; ou presenter une differenciation divergente. Dans ce dernier cas le contingent le plus souvent rencontre est de type epidermoide ou eccrine. Des observations isolees ont signale une differenciation lymphoepitheliale, melanocytaire, neuroblastique, leiomyosarcomateuse et rhabdomyosarcomateuse. Par ailleurs le caractere primitif ou secondaire de la lesion est parfois difficile a affirmer. L’expression diffuse et homogene de la cytokeratine 20 constitue une aide precieuse en faveur du caractere primitif de la lesion, elle manque cependant de sensibilite. Nous rapportons le cas d’un CNEP particuliers par 1 : une differenciation de type pilomatricome, un tel aspect n’a, a notre connaissance, jamais ete signale 2 : une absence d’expression de la CK 20 contrastant avec l’expression diffuse des marqueurs neuroendocrines. Le contingent pilaire dominant retrouve aussi bien sur la lesion initiale que sur la metastase ganglionnaire permettait d’affirmer le caractere primitif de la tumeur ; ce que confirmait la negativite du bilan d’extension paraclinique complet fait a deux reprises.

The role of lymphocytes in the specific defence against L. infantum has been well established, but the part played by polynuclear neutrophil (PN) cells in controlling visceral leishmaniasis was much less studied. In this report we examine in vivo the participation of PN in early and late phases of infection by L. infantum. Promastigote phagocytosis and killing occurs very early after infection, as demonstrated by electron microscopy analyses which show in BALB/c mouse spleen, but not in liver, numerous PN harbouring ultrastructurally degraded parasites. It is shown, using mAb RB6-8C5 directed against mature mouse granulocytes, that in chronically infected mice, long-term PN depletion did not enhance parasite counts neither in liver nor in spleen, indicating that these cells are not involved in the late phase of L. infantum infection. In acute stage of infection, in mouse liver, where L. infantum load is initially larger than that in spleen but resolves spontaneously, there was no significant effect of neutrophils depletion. By contrast, early in infection the neutrophil cells crucially contributed to parasite killing in spleen, since PN depletion, performed before and up to 7 days after the parasite inoculation, resulted in a ten-fold increase of parasite burden. Taken together these data show that neutrophil cells contribute to the early control of the parasite growth in spleen but not in liver and that these cells have no significant effect late in infection in either of these target organs.