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J F Michiels

Publications and source records attributed to J F Michiels.

At least 109 records · Page 6Linked to original sources
PubMed1993

[Acute Staphylococcus aureus myocarditis in AIDS. 2 cases].

The authors report two cases of acute myocarditis due to Staphylococcus aureus in patients with AIDS. There was no history of opportunist infections in either case but the CD4 lymphocyte levels were very low. The myocarditis caused acute cardiac failure and death. Histological examination showed microabscesses filled with Gram positive cocci throughout the myocardium. Bacteriological studies identified the Staphylococcus aureus. Staphylococcus aureus myocarditis without endocardial or pericardial involvement is very rare. It is the result of septic emboli in the cardiac microcirculation. Bacterial myocarditis has rarely been diagnosed in HIV positive patients. Both our cases featured severe cell-mediated immunodeficiency without associated neutropaenia. The decreased bactericidal activity of the neutrophil polynuclears and/or a deficit in the immunity mediated by the B-cell lymphocytes in AIDS could explain the lethal septic complications observed in our two cases.

AIDS-Related Opportunistic Infections↗
PubMed1993

[Histological aspects of mycotic infections in acquired immunodeficiency syndrome (AIDS)].

After some general epidemiological data concerning mycoses occurring during the acquired immunodeficiency syndrome (AIDS), the role of the pathologist in the diagnosis of mycotic diseases is reviewed. Histological methods and criteria allowing fungal identification in tissues are described. Changes in the inflammatory reaction in contact with mycoses arising in these immunodeficient hosts are reported. The various mycoses observed in HIV positive patients are then reviewed as well as their morphological features and their various sites.

AIDS-Related Opportunistic Infections↗
PubMed1993

Horny perifollicular mucinosis. An atypical pityriasis rubra pilaris-like eruption associated with HIV infection.

We present a case of pityriasis rubra pilaris (PRP)-like eruption, in association with human immunodeficiency virus (HIV) infection, clinically characterized by follicular papules with some elongated spines and comedo-like lesions. The lesions were located on the back, flanks, and proximal extremities. Orthokeratotic follicular plugs and perifollicular mucinous degeneration were consistently observed on three biopsies. The most characteristic histological features of PRP were absent. To our knowledge, this is the first reported case of this kind. Such a case could suggest an atypical PRP modified by HIV infection. It is also possible that it represents a new entity associated with advanced HIV infection (horny perifollicular mucinosis).

Adult↗
PubMed1993

[Bacillary angiomatosis of the oral cavity in AIDS. A differential diagnosis of mucosal Kaposi's sarcoma].

The diagnosis of bacillary angiomatosis (BA) was performed on a biopsy of a reddish nodular lesion of the gingival mucosa, in a patient seropositive for the H.I.V. It was based on the histopathological features, and by the demonstration of bacilli both on the Warthin-Starry stain and the electron microscopic study. A treatment by erythromycin was quickly effective. BA is an opportunistic infection seen essentially in patients with A.I.D.S., most often causing cutaneous involvement. The causative pathogen is Rochalimaea henselae. BA of the oral cavity is very rare. This infection can be mistaken with Kaposi sarcoma on its clinical appearance.

AIDS-Related Opportunistic Infections↗
PubMed1993

[Toxoplasmosis in AIDS patients. Pathoclinical study of 78 cases].

We report 78 cases of toxoplasmosis diagnosed between 1987 and 1992, from an autopsy study of 205 patients infected by the human immunodeficiency virus (HIV). Of the 78 patients 22 were females (28%) and 56 males (72%). Risk factors were as follows: intravenous drug addiction (44 cases, 56%), homosexuality or bisexuality (18 cases; 36%) and multiple blood transfusions (6 cases). Cerebral toxoplasmosis (CT) was diagnosed in 73 cases (93%) and was characterized by abscesses (59 cases), diffuse encephalitic lesions (8 cases), isolated cysts without inflammation (3 cases) and hemispheric involvement with ventricular hemorrhage (3 cases). Cerebral involvement were isolated (55/78 cases; 70%) or associated with multi-visceral diffusion (18/78 cases; 23%). Isolated extracerebral localization was observed in 5 cases. The most frequent extracerebral sites were: cardiac (21 cases), pulmonary (14 cases) and pancreatic (7 cases). Immunohistochemical study with anti Toxoplasma gondii antibodies allowed to a diagnosis of extracerebral localization in 8 cases. Ultrastructural features of Toxoplasma gondii were studied on post mortem myocardial samples (2 cases) open lung biopsy (1 case) and bladder biopsy specimen (1 case). Antemortem diagnosis of cerebral toxoplasmosis was performed on CT-scan in 59/73 (80%). Antemortem diagnosis of extracerebral toxoplasmosis was performed or suspected in 8/23 cases (34%): by isolation of trophozoites in bronchoalveolar lavage (2 cases), on an open lung biopsy (1 case) and on a bladder biopsy specimen (1 case), and by clinical and echocardiographic data (4 cases). Anti-toxoplasmic serology allowed to the diagnosis of toxoplasmosis in 12/78 cases (15%) by showing high levels of IgG in the serum.(ABSTRACT TRUNCATED AT 250 WORDS)

AIDS-Related Opportunistic Infections↗
PubMed1993

[Disseminated infection due to Scedosporium apiospermum in liver transplantation. Differential diagnosis from invasive aspergillosis].

A case of fatal disseminated infection due to Scedosporium apiospermum occurring after liver transplantation is reported. Diagnosis was made at autopsy, as numerous fungal colonies were found in the lungs, heart, brain, kidney, spleen and liver. Scedosporium apiospermum was identified in pulmonary, cerebral and myocardial specimens by Sabouraud's glucose agar cultures. Infections due to Scedosporium (S. apiospermum ou Pseudallescheria boydii) occur in immunocompromised hosts, particularly after organ transplantation, and realize severe invasive fungal infection. Scedosporiosis is much more rare than aspergillosis and can be only identified by mycological study. This diagnosis is rarely performed during life time and allows an effective treatment by imidazoles.

Aspergillosis↗
PubMed1993

[Leiomyosarcoma of the liver: a case treated by transplantation].

A 68 year old woman with primary hepatic leiomyosarcoma, impairement of general status and right upper quadrant pain was diagnosed with liver tumor by sonography, CT scan and nuclear magnetic resonance imaging. Angiograms showed a hypervascular tumor. The patient was treated by hepatic transplantation but died 15 days after operation. The diagnosis of leiomyosarcoma was established by immunohistochemical and ultrastructural studies; the primary nature was confirmed by necropsy. Diagnostic and therapeutic features of primary hepatic leiomyosarcoma--the 19th case reported in the literature--are discussed.

Aged↗
PubMed1993

Expression in transgenic mice of the large T antigen of polyomavirus induces Sertoli cell tumours and allows the establishment of differentiated cell lines.

The large T antigen of polyomavirus (PyLT) efficiently immortalizes rodent fibroblasts, but, unlike SV40 T antigen, it is not sufficient to achieve complete oncogenic transformation. We analysed a series of transgenic mouse families that express the PyLT protein under control of the viral enhancer-promoter region. In all of them, the transgene was expressed in the seminiferous epithelium of the testis (Sertoli and germ cells), with no pathological consequences during most of the animals' lives. However, every old male developed large bilateral tumours of the testes, generated by the proliferation of Sertoli cell derivatives. Cell lines could be readily established both from the tumours and from the still apparently normal testis before the onset of tumoral growth. They retained in vitro morphological and ultrastructural features characteristic of Sertoli cells. But, in addition to this major Sertoli component, the maintenance of a cellular contingent of germinal origin was suggested by the expression of genes that are normally transcribed during the premeiotic and early meiotic stages of spermatogenesis (LDH-X, Hox1.4 and c-kit). The two cell types remained tightly associated, even at late passages in culture, and could not be separated by conventional cloning procedures. This association in culture of the two cell types whose interaction is critical for spermatogenesis may provide a useful tool for its molecular analysis.

Animals↗
PubMed1993

[Cytological study of the duodenal mucosa during chronic diarrhea in HIV-positive patients].

The cytologic findings of duodenal smears in diarrheic HIV-positive patients were compared with results of histologic and ultrastructural studies. This study included 50 diarrheic patients undergoing upper gastrointestinal endoscopy. Duodenal biopsies were taken with touch preparations. Smears were stained with Giemsa and then with Ziehl-Neelsen or the PAS method. The biopsy specimens were then processed in a standard fashion for histologic and electron microscopy examination. Cytologic findings included 8 cases of intestinal microsporidiosis, 4 cases of cryptosporidiosis, and 3 cases of atypical mycobacteriosis. Histologic and ultrastructural studies confirmed these diagnoses and showed 8 cases of CMV enteritis, of which 4 were associated with other enteric pathogens. Duodenal cytology complements endoscopic biopsy in the work-up of diarrhea in AIDS patients and may provide a rapid diagnosis especially in the case of intestinal protozoonosis or atypical intestinal mycobacteriosis.

AIDS-Related Opportunistic Infections↗
PubMed1993

[Rhino-orbito-cerebral mucormycosis caused by Rhizopus oryzae.A typical case in a cirrhotic patient].

The rhino-orbito-cerebral mucormycosis is an acute rapidly progressive fungal infection. This disease is caused by a zygomycetes fungus, most often from the Rhizopus genus. This fungus is saprophitic of the nasal cavity and paranasal sinuses. It becomes pathogenic in some particular conditions, specially during diabetes mellitus. Histopathological study is the only method allowing the diagnosis, by revealing the tissue invasion by characteristic hyphae. Mycologic study allows a definitive identification of the fungus. The authors report a case of rhino-orbito-cerebral mucormycosis in a 44 year-old woman with cirrhosis. She presented an acute blindness and ophthalmoplegia. Despite of a rapid histologic diagnosis from the nasal and ethmoidal biopsies, the patient died 3 days after.

Adult↗
PubMed1992

Interleukin-6 production in high-grade B lymphomas: correlation with the presence of malignant immunoblasts in acquired immunodeficiency syndrome and in human immunodeficiency virus-seronegative patients.

The mechanisms leading to malignant cell proliferation may differ between the different histologic forms of high-grade non-Hodgkin's lymphomas. To analyze the potential role of interleukin-6 (IL-6) as a growth factor for lymphomatous cells in these different forms, the in situ production of this cytokine was analyzed in lymphomatous samples taken from 24 patients, 18 of whom were human immunodeficiency virus (HIV) infected. Eleven Burkitt's lymphomas (BLs), seven diffuse large-cell lymphomas, and six immunoblastic lymphomas were studied. In situ hybridization experiments showed that the IL-6 gene was expressed in all tissues. The number of IL-6 gene-expressing cells was 7 times higher in the non-BLs than in the BLs, and it was 17 times higher than that of 14 control lymph nodes displaying a benign follicular hyperplasia. Analysis of individual cases indicated that the level of IL-6 gene expression was strongly correlated with the presence of immunoblasts within the malignant clone. In contrast, this level was not correlated with the presence of Epstein-Barr virus genome in the lymphoma or with the HIV status of patients. Immunohistochemical studies with an anti-IL-6 monoclonal antibody showed that IL-6 was produced in non-BLs, but not in BLs. In the former, IL-6 mainly originated from reactive, nonmalignant cells. Immunohistochemical analyses of non-BLs also showed that malignant cells produced the 80-Kd chain of the IL-6 receptor. Taken together, these results suggest that IL-6 may act as a growth factor in some forms of high-grade B lymphomas. The presence of immunoblasts may be an indicator of such forms.

Acquired Immunodeficiency Syndrome↗
PubMed1992

[Blastomycosis localized in the brain stem].

A 33-year old male Tunisian developed, without any apparent cause, an abscess of the brainstem which was shown by various mycological investigations to be due to a Blastomyces dermatitidis infection. This case is of interest not only because of the exceptional location of the abscess in the brainstem, but also because of its treatment: this was the first case where the fluconazole-flucytosine combination was used against blastomycosis with fully satisfactory results after a 28-month follow-up.

Adult↗
PubMed1992

Primary uveal B immunoblastic lymphoma in a patient with AIDS.

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.

Adult↗