Biomedical subjects
Publications and source records attributed to M Hanssens.
Primary acquired conjunctival melanosis presents as a unilateral conjunctival pigmentation, mostly in middle-aged patients, with a strong tendency to progress to malignancy. The clinical picture is specific and doesn't cause major diagnostic problems. It is important to recognize the entity, to observe it closely and treat it early and adequately.
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Five antibodies that stained renin in the kidney were used to investigate the presence of renin in human placenta and fetal membranes. Despite a large number of experimental approaches to enhance penetration of the immunoglobulins, only two of them showed immunostaining in placenta and fetal membranes. Staining was found in placental syncytiotrophoblast, the amnionic epithelium overlying the placenta, and in glandular epithelial cells present in the decidua adhering to the fetal membranes. It was most consistent, however, in a small infiltrating cell type dispersed through the fetoplacental layers. The two antibodies that revealed immunostaining in all preparations showed high affinity cross-reactivity with cathepsin D. Among other, less plausible, explanations, this raises the possibility that the bulk of 'renin' found in placenta and fetal membranes is not identical to renal renin, but may be cathepsin D or a substance related to both cathepsin D and renin.
Chorionic trophoblast, decidual cells, and macrophages have all been named as the site of renin in the placental membranes. To establish more clearly the nature of the renin-containing cells in the placental membranes, double immunostaining techniques were used to stain renin and specific cell markers in the same tissue sections. Cytokeratin was selected as an ectodermal cell marker and CD68 as a cytoplasmic macrophage marker. Cross-binding between antibodies was prevented by blocking species-related binding sites between the first and second sequence of the double-immunostaining procedures and by using highly selective immunostaining techniques in the second sequence. The results clearly show renin immunostaining in CD68-positive macrophages and not in cytokeratin-positive trophoblast. The anti-renal renin monoclonal antibody showed high affinity cross-reactivity with cathepsin D, another aspartic proteinase that can release angiotensin I from angiotensinogen. This should be seen in the context of earlier findings that only two of four anti-renal renin monoclonal antibodies showed staining in uterine and placental tissues and both cross-reacted with cathepsin D. The results indicate that differentiation between renin and cathepsin D and, possibly, other substances with shared properties and epitope homology deserves more attention than it has received thus far.
A thirty-eight year-old man, treated medically since 1985 for a chronic pancreatitis, showed a choroidal infiltrate in the superior mid periphery of the left fundus. A thorough systemic examination could not reveal an underlying cause. The differential diagnosis of the lesion included metastasis, intraocular lymphoma and sarcoidosis. Two months later the lesion had increased both on fundoscopy and echography and was accompanied by a serous macular detachment. A choroidal biopsy showed a moderately well differentiated mucinous adenocarcinoma. The primary site could not be determined. The mucinous character is rather suggestive for a gastrointestinal origin. Gastro intestinal choroidal metastases, and more specifically the pancreatic ones, are however rare.
The term "pseudoglioma" designates a heterogeneous group of diseases that may be confused clinically with retinoblastoma. The authors report the case of a one year old boy with leucocoria and exotropia of the left eye. Clinical examination disclosed a retrolental whitish vascularized mass. As a retinoblastoma could not be excluded with certainty, the blind eye was enucleated. Pathological examination showed a retinal vascular anomaly compatible with Coats' disease. The authors discuss the differential diagnosis of leucocoria and pseudoglioma.
A 71-year old woman complains of painless inflammation, discharge and decreased vision at the right eye since two weeks. Eight years before she was operated at this eye for a nasally located pterygium and received adjuvant radiotherapy. On examination a necrotizing scleritis was seen which rapidly involved the cornea and was infected by Pseudomonas. Despite intensive antibiotherapy the sclerokeratitis extended further and eventually lead to enucleation. Surgically induced scleritis-especially after pterygium surgery with adjuvant radiotherapy-and complicating Pseudomonas infection are discussed.
In four patients, two men and two women aged 73, 68, 84 and 72 years respectively, reversible cholestatic liver injury was seen 28-35 days after the start of treatment with amoxycillin-clavulanic acid (Augmentin). This rare complication of amoxycillin-clavulanic acid treatment is characterized by a relatively long latent period before the onset of symptoms or biochemical abnormalities, which makes early recognition difficult. The mechanism responsible for this idiosyncratic cholestasis is unknown.
In normal pregnancy trophoblast invades the spiral arteries and produces the physiological fibrinoid degeneration of the vessel wall. In pre-eclampsia, physiological change is restricted and pathological change develops in the non-invaded arteries, including acute atherosis. This study was undertaken to determine if lipoprotein(a) [Lp(a)], which is associated with atherogenesis is present in the wall of spiral arteries that have undergone physiological and pathological change. One hundred and sixteen spiral arteries were examined from 18 normal and 24 severe pre-eclamptic pregnancies. Lp(a) was detected in all atherotic and necrotic lesions, in 57% of spiral arteries with medical disorganization or hyperplasia, and in 45% of those with physiological change. When Lp(a) was detected differences were found in the amount seen: it was most in atherosis, less in necrosis, less still in medical change, and least in physiological change. For the same vascular change generally more Lp(a) was detected in the pre-eclamptic group than in the normal group. The detection of Lp(a) helps to distinguish physiological fibrinoid from atherotic and necrotic fibrinoid. Many atherotic and necrotic areas initially overlooked using standard histology were highlighted using immunohistochemistry. Atherosis can develop in spiral arteries that have been invaded by trophoblast. In those with pre-eclampsia, atherosis was found in 56% of decidual but only in 8% of myometrial spiral arteries. Small areas of necrosis were common in physiologically changed arteries from normal pregnancies.
OBJECTIVE: To investigate trophoblast invasion and vascular changes in placental bed spiral arteries in normal and severe pre-eclamptic pregnancies. DESIGN: A histological and immunohistochemical study of placental bed biopsies containing spiral arteries. SETTING: The University Hospital, Leuven, Belgium. SUBJECTS: Twenty-one placental bed biopsies from 21 normal pregnancies and 24 placental bed biopsies from 24 severe pre-eclamptic pregnancies, taken at caesarean section. OBSERVATIONS: Histological and immunohistochemical appearance of spiral arteries (stained with haematoxylin and eosin), periodic acid schiff, and a monoclonal antibody to low molecular weight cytokeratin. RESULTS: One hundred and twenty-seven spiral arteries were studied. In the 21 biopsies from clinically normal pregnancies at term, 100% of the decidual spiral arteries and 76% of the myometrial arteries showed trophoblast invasion. In the 24 biopsies from women with severe pre-eclampsia, trophoblast invasion was seen in 44% and 18% of the decidual and myometrial segments, respectively. Endovascular trophoblast invasion was complete, partial or isolated. A variety of morphological features was present not only in different spiral arteries from the same biopsy but also in different segments of the same artery. The vascular change most commonly associated with normal pregnancies was physiological change and subintimal thickening of both segments of the spiral arteries. In pre-eclampsia medial disorganisation and hyperplasia in the myometrial arteries and acute atherosis in decidual arteries were common. CONCLUSION: Endovascular trophoblast did not show an all or none invasive phenomenon in normal and pre-eclamptic pregnancies. More decidual than myometrial arteries were invaded in both groups of patients, and there was a gradient in the percentage of decidual and myometrial arteries invaded from normal pregnancy to pre-eclampsia. Morphological features in one spiral artery may not necessarily be representative of all of those in a placental bed.
A translocation between chromosomes 7 and 8 was found in several members of a family. We describe two family members with an unbalanced form of this translocation with the derivative of chromosome 7:der(7),t(7;8)(q34;q24.1). Both present multiple congenital systemic anomalies and ocular aberrations. Of those the coloboma of the optic disc is the most obvious. We discuss the pathology of the eyes of one of our patients.
A patient with non-Hodgkin lymphoma with low grade malignancy complained of gradual visual loss. Symmetric multiple deep retinal yellow dots were disseminated in both fundi. The patient developed progressive papilledema associated with further decreasing visual acuity. Other signs of uveitis were absent. A chorioretinal biopsy confirmed the intraocular lymphomatous involvement. Cerebrospinal fluid revealed abnormal lymphocytes and local Ig-M production thus proving the lymphomatous meningeal involvement.
OBJECTIVE: Because pregnant women with diabetes have an increased risk of preeclampsia, we tested the hypothesis that urinary excretion of thromboxane metabolites is increased in diabetic pregnancies without evidence of preeclampsia at the time of testing. STUDY DESIGN: Urinary excretion of thromboxane A2 metabolites (either 2,3-dinor-thromboxane B2 or 11-dehydro-thromboxane B2) was measured in 24 type I pregnant diabetic individuals and in 20 women with normal pregnancies between 28 and 32 weeks' gestation. RESULTS: The amount of 2,3-dinor-thromboxane B2 and 11-dehydro-thromboxane B2 in the urine of pregnant women with diabetes (1727 +/- 415 and 827 +/- 276 pg/mg creatinine) was significantly higher than in women with normal pregnancies (638 +/- 218 and 178 +/- 145 pg/mg creatinine) (p < 0.002 and p < 0.001). CONCLUSION: Our findings support a role for thromboxane in the pathogenesis of preeclampsia.
A patient with neurosyphilis, presenting with severe ocular impairment due to optic neuropathy, is described. In such a case, a low index of clinical suspicion and improper use of syphilitic serologic tests may delay diagnosis. However, specific tests of serum and cerebrospinal fluid are mandatory for the diagnosis. Treatment evaluation necessitates the follow-up of serology and cerebrospinal fluid cell count. Recent changes of therapy recommendations in subjects with neurosyphilis and in those syphilitic patients co-infected with HIV are mentioned.
A 49 year-old man consulted in March 1980 for pain, eyestrain and decreased vision at the right eye. He presented a slightly elevated and transparent lesion, strictly limited to the corneal epithelium and treated with eyedrops until November 1980. The patient was seen again 12 years later in October 1992 with still the same complaints and a practically unchanged corneal lesion. The diagnosis of primary corneal epithelial dysplasia (Corneal Intraepithelial Neoplasia-Corin) was made and the abnormal epithelium completely removed under local anesthesia. After the operation the cornea became normal again and the patient free of complaints. The authors discuss the clinical symptoms, pathology, pathogeny and treatment of primary corneal epithelial dysplasia (Corneal Intraepithelial Neoplasia-Corin).
Merkel cell carcinoma, a neuroendocrine tumor, is a highly invasive cutaneous neoplasm, which rarely affects the eyelids. This tumor must be treated aggressively to minimize the changes of local recurrence and regional or distant metastasis. In this paper, we describe a 78-year-old woman who had two recurrences of this neoplasm after consecutive local excisions. We describe the histopathological findings and emphasize the differential diagnosis with other neoplasms, as the therapeutic approach is different.
The major goal in the evaluation of posterior uveal tumours is to determine whether an intra-ocular malignancy is present and whether intervention is necessary. Small uveal pigmented tumours can safely be managed by observation until growth is documented. However, extensive evaluation for each suspicious lesion is necessary in order not to miss any signs of malignancy. A case is presented of a 41 year old male patient with orbital pain as initial symptom of a choroidal melanoma. Fluorescein-angiography revealed signs of double circulation. Abnormal choroidal vessels inside the tumour showed up clearly on indocyanine-green angiography. By ultrasonography we were able to detect scleral perforation and extra-scleral extension. Computed tomography confirmed the extra-scleral extension. As there were no signs of metastasis, an orbital exenteration with sparing of the eyelids was performed. Histopathology is compared with the results of clinical investigation.
A man with a 2.5 year history of chronic papillary conjunctivitis was diagnosed as having "floppy eyelid syndrome". This syndrome, first described in 1981, is characterized by loose upper eyelids that evert readily on elevation of the lid, a chronic papillary conjunctivitis and a soft rubbery tarsus. The condition is resistant to any form of medical treatment but responds well to a horizontal lid shortening procedure. The etiology is unknown but the present report suggests that an abnormality of the structure of the orbicularis muscle may play a role.