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J F Michiels

Publications and source records attributed to J F Michiels.

At least 73 records · Page 4Linked to original sources
PubMed1996

[Comparative profitability of hepatic biopsy and microbiological tests in patients with HIV infection].

OBJECTIVES: Diagnostic liver biopsy is proposed in HIV-positive patients who present unexplained fever. This invasive procedure is truly useful if it allows establishing a difficult diagnosis or improves survival rate. We conducted a retrospective study to determine the diagnostic and prognostic power of liver biopsy in HIV-positive patients with fever. METHODS: One hundred thirty-eight liver biopsies were performed in 129 patients. Utility was defined as demonstration of the pathogen or identification of a tumoral process. RESULTS: The liver biopsy met the utility criteria in 27 cases showing mycobacterial infections (n = 22) and herpes hepatitis, type 1 herpes simplex virus, cytomegalovirus and cryptococcosis infections (n = 1 each). These last 4 diagnoses were also possible with other tests. Comparing non-contributive liver biopsies (n = 111) with those demonstrating hepatic mycobacterial infection (n = 22) showed that the two groups were not different in terms of demographic data. Splenomegalia was more frequent in the non-contributive group (68% vs 37%, p = 0.007) as was superficial lymph node enlargement (45% vs 12%, p < 10(-3)). Laboratory tests were not discriminating. Mycobacterial infection was diagnosed in 22 patients in the non-contributive group. Bacteriological samples were positive for mycobacterium in 20 of the 22 patients in the contributive group. The mean delay to the first positive test for mycobacterium was 15 +/- 8 days compared with 30 +/- 10 days for liver tissue cultures. Mean survival after liver biopsy was 10 months: patients with a positive Ziehl-Neelson stain on the liver biopsy did not have a longer survival (9.7 +/- 7.6 vs 10.2 +/- 10.4 months). CONCLUSION: In most cases, liver biopsy in HIV-positive patients with fever provides a diagnosis which can be obtained with non-invasive techniques without improving prognosis.

AIDS-Related Opportunistic Infections↗
PubMed1996

Benign fibrous mesothelioma of the pleura: MR study and pathologic correlation.

Benign fibrous mesothelioma of the pleura is a rare tumor of mesodermal origin. We describe the MR findings in three pathologically proven cases. All three tumors were imaged by MR as well-circumscribed lesions with smooth margins in contact with the pleura, but without chest wall invasion. Their low signal intensity on T1- and T2-weighted sequences reflect their fibrous nature. In one case a pedicle connecting the tumor to the chest wall was visualized on a sagittal MR scan. In two cases gadolinium-enhanced T1-weighted gradient echo sequences revealed intense contrast uptake by the tumor correlated with the intratumoral hypervascularization noted by histologic examination. Although the number of cases presented is small, MR seems to be the most accurate imaging modality in the assessment of the diagnosis.

Aged↗
PubMed1996

Cyclophosphamide cystitis as a model of visceral pain in rats. A survey of hindbrain structures involved in visceroception and nociception using the expression of c-Fos and Krox-24 proteins.

The evoked expression of the immediate early gene-encoded proteins c-Fos and Krox-24 was used to study activation of hindbrain neurons as a function of the development of cyclophosphamide (CP) cystitis in behaving rats. CP-injected animals received a single dose of 100 mg/kg i.p. under transient volatile anesthesia and survived for 1 to 4 h in order to cover the whole postinjection period during which the disease develops. CP-injected groups included: (1) animals with minor simple chorionic edema, an early characteristic of inflammation (1 h postinjection); (2) animals with well-developed simple chorionic edema (2 h postinjection); (3) animals with mild inflammation (chorionic edema accompanied by epithelial cleavage; 3 h postinjection); and (4) animals with complete inflammation (4 h postinjection). In addition to onset of chorionic edema, the earliest postinjection period also included the general aspects of the nervous reaction consecutive to the injection process (handling, transient volatile anesthesia and postanesthesia awakening, abdominal pinprick, CP-blood circulating effects). Controls included both noninjected animals and saline-injected animals surviving for the same times as CP-injected ones. Quantitative results come from c-Fos expression. It has been shown that: (1) saline injection is a significant stimulus for only nucleus O and central gray pars alpha and nucleus medialis of the dorsal vagal complex; (2) all structures driven by CP injection (nucleus O and central gray pars alpha, locus coeruleus, Barrington's nucleus and parabrachial area mostly in its ventral and lateral subdivisions, dorsal vagal complex, ventrocaudal portion of lateral bulbar reticular formation) responded vigorously shortly after injection, but only two (dorsal vagal complex, ventrocaudal portion of lateral bulbar reticular formation) showed increased or renewed activity when cystitis completely developed, i.e., when noxious visceral inputs reached highest levels. Regarding the sequential activation of these structures in relation to postinjection time, evidence is given that: (1) a large variety of hindbrain structures are differentially involved in either the general reaction consecutive to the injection process or to various degrees of cystitis; (2) these structures extend from the brain-spinal cord to the pons-mesencephalon transitional junction levels; (3) the two structures most powerfully driven by visceronociceptive inputs are also the most caudal ones, being located at the brain-spinal cord junction level; and (4) the dorsal vagal complex could be the main hindbrain visceral pain center, with three particular subdivisions, the nucleus medialis, nucleus commissuralis, and ventralmost part of area postrema, being involved.

Animals↗
PubMed1996

Cervical intra-epithelial neoplasia in women infected with human immunodeficiency virus.

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 < 0.001). 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.

Adolescent↗
PubMed1996

Liver biopsy is not useful in the diagnosis of mycobacterial infections in patients who are infected with human immunodeficiency virus.

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.

AIDS-Related Opportunistic Infections↗
PubMed1996

[Treatment of abdominal aortic aneurysms: importance of the bifurcated prosthesis].

Despite the increasing use of tube grafts to treat aortic aneurysms, bifurcated prostheses remain the most frequent solution. Advocates of the tube graft emphasize faster positioning and lower operative morbidity and mortality rates. However, the condition of the aortic orifice (where atheromatous lesions are maximal) and the aneurysmal or occlusive iliac disease frequently associated with aortic aneurysms usually require use of a bifurcation prosthesis for complete treatment of aortoiliac lesions.

Aortic Aneurysm, Abdominal↗
PubMed1996

[White papulosis of the neck. Clinical aspects of pseudoxanthoma elasticum].

INTRODUCTION: Acquired elastolysis of the papillary dermis simulating pseudoxanthoma elasticum and white papulosis of the neck are two skin diseases with clearly limited borders. The two entities can be distinguished clinically when papulae converge into yellowish-white patches and histologically by complete absence of the elastic network in the papillary dermis without thickening of the collagen network in the superficial and mid dermis. CASE REPORT: We observed a patient with the clinical and histological criteria for acquired elastolysis of the papillary dermis. Histological examination showed a thick collagen network as described in white papulosis of the neck. DISCUSSION: This case clearly demonstrates the histological continuum between these two entities. A review of the literature also provided evidence of borderline forms, leading us to propose grouping them together. Elastolysis of the papillary dermis would appear to be a relatively specific histological sign differentiating white papulosis of the neck, in a general sense, and acquired elastosis of the mid dermis. Two factors could explain the rare observations of acquired elastosis of the mid dermis in patients with acquired elastosis of the papillary derma: use of the Verhoeff Van Gieson stain without an internal control and imprecise localization of the biopsy.

Aged↗
PubMed1996

[Subcutaneous cysticercosis].

INTRODUCTION: The case of a patient originated from Angola who presented subcutaneous and neurologic cysticercosis is reported. OBSERVATION: The patient was referred for the etiological diagnosis of recurrent seizures. The diagnosis was made by histologic examination of a subcutaneous lesion. COMMENTS: We review the clinical characteristics of subcutaneous cysticercosis. The association of subcutaneous nodules and signs of central nervous involvement occurring in a patient originating from an area where cysticercosis is endemic, must be suspected of cysticercosis.

Adult↗
PubMed1995

[Persistent diarrhea in HIV infected patients: role of Enterocytozoon bieneusi].

OBJECTIVES: To determine the epidemiologic, clinical and aetiologic features of chronic diarrhoea in patients with human immunodeficiency virus (HIV) infection. METHODS: Between January 1992 and April 1993, all HIV positive patients with chronic diarrhoea were enrolled in a prospective study. There were 46 patients in the study group including 33 (22 homosexuals) in stage C according to the 1993 Centers for Disease Control classification. RESULTS: Thirty-four pathogenic agents were isolated in 26 of the patients (57%). Enterocytozoon bieneusi was the most frequently found pathogen (11 patients, 24%) followed by Cryptosporidium sp (8 patients). Enterocytozoon bieneusi was found in association with other pathogens in 7 patients. All patients with microsporidiosis were in stage C (p = 0.04) and had a longer duration of diarrhoea (19.6 vs 9.8 weeks, p = 0.03), greater weight loss (9.6 vs 2.1 kg, p = 0.0003) and a lower Karnofsky index (48% vs 67%, p = 0.01). Prophylaxy with dapsone or pyrimethamine during the 3 months prior to inclusion had been more frequent (p = 0.04 and p = 0.05 respectively) in patients without microsporidiosis. CONCLUSION: Microsporidiosis should be suspected as a probable cause of chronic diarrhoea in HIV positive patients with a CD4 count < 100/mm3. Multiple infections may be a factor leading to treatment failure. Microsporidiosis seems to be linked to homosexual intercourse.

AIDS-Related Opportunistic Infections↗
PubMed1995

Primary bronchogenic squamous cell carcinoma in children: report of a case and review of the literature.

The authors report a case of primary bronchogenic squamous cell carcinoma (SCC) revealed by recurrent pneumonia in an 11-year-old boy. Four years after complete surgical resection followed by external radiotherapy, the patient is currently relapse- and metastasis-free. To our knowledge, this is only the sixth pediatric case of primary bronchogenic SCC reported to date.

Carcinoma, Squamous Cell↗
PubMed1995

Thyroid spindle epithelial tumor with thymus-like differentiation (the "SETTLE" tumor). An immunohistochemical and electron microscopic study.

An intrathyroid primary epithelial spindle-cell tumor with mucous cysts is described in a 9-year-old child. Histologically, this well-circumscribed tumor exhibited a nodular pattern, a prominent spindle cell component with minimal pleomorphism, and well-differentiated mucinous glands within fibrous bands. The spindle cells demonstrated diffuse immunopositivity for cytokeratin and vimentin. Electron microscopy of tissue sections demonstrated that cells contained bundles of cytoplasmic tonofilaments and numerous desmosomes. The light and electron microscopic features and immunohistochemical profile of this tumor were similar to those of recently described thyroid tumors that have been called "SETTLE" tumors (i.e., spindle epithelial tumor with thymus-like differentiation). These uncommon tumors can be considered intrathyroid thymoblastomas and must be regarded as potentially malignant lesions.

Child↗
PubMed1995

Cyclophosphamide cystitis as a model of visceral pain in rats: model elaboration and spinal structures involved as revealed by the expression of c-Fos and Krox-24 proteins.

The evoked expression of the immediate early gene (IEG)-encoded proteins c-Fos and Krox-24 was used to monitor spinal visceronociceptive processing that results from cyclophosphamide cystitis in behaving rats. Animals received a single dose of 100 mg/kg i.p. of cyclophosphamide and survived for 30 min to 5 h. Longer survival times were not considered because of ethical considerations. Cyclophosphamide-injected animals developed characteristic behavioral signs in parallel with development of bladder lesions and spinal evoked expression of IEG-encoded proteins. Histological examination of the urinary bladder was used to evaluate the degree of cystitis and as a criterion for selection of groups of animals to be quantitatively analyzed. Controls consisted of freely behaving animals including control (un-injected), sham (saline-injected) or diuretic (furosemide-injected) animals. Behavioral modifications consisted of lacrimation, piloerection, assumption of a peculiar "rounded-back" posture, which was accompanied by head immobility and various brief "crises" (tail hyperextension, abdominal retractions, licking of the lower abdomen, backward withdrawal movements). Abnormal behaviors, which first appeared (lacrimation, piloerection) at the end of postinjection hour 1, progressively increased in severity (rounded-back posture) over the following 90 min to reach a plateau at about postinjection hour 2; the rounded-back posture was maintained up to time of death. Histological modifications of bladder tissue were assessed using a 4-grade scale in a blind setting. The 1st grade consisted of control or sham animals with no bladder lesion; 2nd grade, animals with simple chorionic edema; 3rd grade, animals with chorionic edema associated with mucosal abrasion, fibrin deposit, and onset of polymorphonuclear leukocyte infiltration; 4th grade, animals with complete cystitis corresponding to an increase in severity and spread of all the signs of cystitis described above plus petechial hemorrhage. Simple chorionic edema was observed from 30 min to 3 h postinjection, but with a progressive increase in severity over time. Edema accompanied by epithelial abrasion was observed for animals that survived 3-4 h postinjection; complete inflammation was observed in animals that survived 4-5 h postinjection. The study of c-Fos- and Krox-24-encoded protein expression demonstrated that few lumbosacral spinal areas were specifically involved in the processing of visceral inputs in response to bladder stimulation. These areas were the parasympathetic column (SPN), the dorsal gray commissure (DGC as the caudal extent of lamina X), and superficial layers of the dorsal horn.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1995

Atypical cutaneous histological features of visceral leishmaniasis in acquired immunodeficiency syndrome.

Cutaneous lesions in Mediterranean visceral leishmaniasis (VL) are very unusual, except for the presence of Leishmania organisms in cutaneous Kaposi's sarcoma in patients with acquired immunodeficiency syndrome (AIDS). We have identified two unusual cutaneous histological features of VL in three patients with AIDS not described previously; two had "silent leishmaniasis," and in the third, Leishmania organisms were present in sweat ducts, suggesting transepithelial elimination through eccrine sweat glands and/or eccrine epithelial tropism.

AIDS-Related Opportunistic Infections↗
PubMed1995

[Targetoid hemosiderotic hemangioma].

INTRODUCTION: Targetoid hemosiderotic hemangioma (THH) is a new vascular disorder, rarely reported. The lesion presents as violaceous papule surrounded by an ecchymotic ring usually measuring less than 1 cm in diameter. Epithelioid endothelial cells with a hobnail appearance, vascular papillary projections and hemosiderin deposits are the histological hallmarks of this entity. OBSERVATION: We report a case fulfilling these criteria. Particular morphologic features were the presence of a very prominent lymphocytic infiltrate, with numerous intraluminal lymphocytes closely associated with the neoplastic endothelial cells, scarcity of siderophages, rought of retiform pattern, predilection of newly formed vessels for muscles of hair erection and eccrine ducts. DISCUSSION: Having regard to these worrisome histologic features the differential diagnosis between THH, Kaposi's sarcoma and newly recognized entities such as lymphangioendothelioma and retiform hemangioendothelioma is discussed.

Diagnosis, Differential↗
PubMed1995

[Colonic Histoplasma capsulatum pseudotumor in AIDS. Morphological and immunohistochemical diagnosis of an isolated lesion].

The authors report a case of a 35-year-old man with acquired immunodeficiency syndrome (AIDS) and a left colonic mass with Histoplasma capsulatum (H. capsulatum). The look-up performed looking for disseminated infection was negative. In the absence of positive cultures, the diagnosis was determined morphologically based on the presence of yeast observed by light and electron microscopy. The diagnosis was also verified by positive immunofluorescence using specific anti-Histoplasma antibodies. Gastrointestinal histoplasmosis is a frequent complication of AIDS, particularly in some endemic areas of America. Association with a disseminated mycotic infection is then common. Histoplasmosis is less frequently diagnosed in Europe and isolated involvement of the colon is exceptional. When the mycological study is not performed or is negative, only morphological and immunohistochemical methods are able to establish the diagnosis and eliminate other mycotic diseases occurring during AIDS.

AIDS-Related Opportunistic Infections↗