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R L Humbel

Publications and source records attributed to R L Humbel.

At least 19 recordsLinked to original sources
PubMed2006

Probably anti-Tr associated paraneoplastic cerebellar degeneration as initial presentation of a squamous cell carcinoma of the lung.

Paraneoplastic cerebellar degeneration (PCD) is the most frequent paraneoplastic syndrome affecting the brain. Until now, anti-Tr associated PCD was only seen in patients with Hodgkin's disease. We report a male patient who presented with a progressive ataxia, affecting predominantly the lower limbs and a cerebellar dysarthria. Extensive diagnostic approach initially showed no evidence of tumor. The patient was found to have anti-Tr antibodies in his serum. Fourteen months after onset of symptoms a whole body PET-scan showed a pathological focus at the right hilus of the lungs. A mediastinoscopy was performed and peribronchial node sampling was done. The anatomopathological analysis revealed a non-well differentiated squamous cell carcinoma. This is the first report about the association between an anti-Tr associated PCD and squamous cell carcinoma.

Aged↗
PubMed2005

Diagnostic value of anti-F-actin antibodies in a French multicenter study.

According to international criteria, autoimmune hepatitis (AIH) type 1 is characterized by the presence of antinuclear or anti-smooth muscle antibodies (SMA) with F-actin specificity. SMA have been found in 85% of AIH patients, but are not specific to this disease, and anti-F-actin specificity is not always verified when SMA are detected. The objective of this study was to determine the diagnostic value of anti-F-actin antibodies in a large population. A multicenter study involving 12 clinical centers was performed. Patients were selected on the basis of the presence of F-actin SMA detected by indirect immunofluorescence (IIF) on rat liver-kidney-stomach sections and was confirmed by IIF on Hep2 cells treated with colchicine, or F-actin dot-blot. The clinical status of patients was determined from their medical records. One hundred sixty-eight patients were included: 76% women, 24% men; mean age of 45 years (range, 2-88 years), with a bimodal age distribution. Sixty percent had AIH type 1, and 40% had another disease. In the group of women younger than 25 years, 90% had AIH type 1. Other pathologies associated with antiactin were other liver diseases (19%), including viral hepatitis C (7%), and non-liver diseases (21%), including connective tissue diseases (12%). Antibody titers were higher in AIH than in other diseases. Antiactin antibodies are of major diagnostic value in AIH, especially in young women; they may be found in other disease settings, but mostly at low levels.

Actins↗
PubMed2000

[Clinical significance of antiribosomal antibodies. Study Group on Autoimmunity (GEAI)].

PURPOSE: Autoantibodies directed against the ribosomal P proteins, P0, P1 and P2 (anti-P), have been related to lupus-related psychosis and/or depression. The diagnostic value of antibodies directed against other ribosomal proteins or 28S RNA (anti-no-P) remains unknown. A multicenter study including ten centers belonging to the study group for autoimmune diseases (GEAI) was conducted in order to determine the diagnostic value of anti-P and anti-no-P antibodies in a large population of patients. METHODS: The patients were selected on the basis of the presence of serum anti-ribosomal antibodies detected by indirect immunofluorescence (IF) on rat liver/kidney/stomach/pancreas sections and human HEp2 cells. The clinical course of all patients was studied using a predetermined survey. The specificity of anti-P antibodies were determined by Western blot. RESULTS: Anti-ribosomal antibodies were found in 82 patients. Fifty-five of them had systemic lupus erythematosus and 27 had another disease. Only 54% of the anti-ribosomal antibodies detected by IF were anti-P and were found in 69% of the patients with systemic lupus erythematosus. Anti-no-P antibodies (46%) were preferably detected in patients who suffered from another disease (78%). In patients with systemic lupus erythematosus, neurological and psychiatric disorders were more frequent in the no-P group (47% vs. 16%, P < 0.01) than arthritis, which was found more frequently in the P group (78% vs. 53%, P < 0.05). CONCLUSION: Anti P antibodies do not constitute a specific diagnostic marker of systemic lupus erythematosus, and lupus-related neuropsychiatric disorders would be preferably associated with the presence of anti no-P antibodies.

Animals↗
PubMed2000

Schnitzler syndrome: heterogeneous immunopathological findings involving IgM-skin interactions.

The Schnitzler syndrome is the association of chronic urticaria, intermittent fever, osteosclerotic bone lesions and a monoclonal IgM gammopathy. It is not yet firmly established whether the monoclonal immunoglobulin component plays a part in the pathophysiology of the urticarial lesions. Immunoblotting on epidermal and dermal human skin extracts as well as immunoelectron microscopic (IEM) studies on Lowicryl K4M-embedded skin sections were performed in three patients with the Schnitzler syndrome. Western blotting on epidermal extracts showed the presence of IgM-kappa antiskin autoantibodies in two patients. These antibodies displayed the same isotype as the monoclonal components and recognized a 280-290-kDa antigen in one patient and a 200-kDa antigen in the other patient. IEM studies showed sparse IgM deposits in the epidermis, around the keratinocytes, near the desmosomes in one patient and dense deposits below the lamina densa, in the region of the anchoring fibrils, in another patient. Antiskin IgM autoantibodies of the same isotype as their monoclonal gammopathies can be present in the serum of some patients with the Schnitzler syndrome. These IgM antibodies seem to deposit in vivo in the epidermis and at the dermal-epidermal junction, in the region of the anchoring fibrils. These findings suggest that the monoclonal gammopathy plays a part in the pathophysiology of the skin rash. They also suggest patient heterogeneity both in the skin antigens that are recognized as well as in their localization.

Autoantibodies↗
PubMed1998

[Prostatic cancer in the Grand Duchy of Luxembourg. Role of PSA].

We reviewed the trends in prostate cancer incidence and mortality in Luxembourg between 1983 and 1995 to discuss the importance of total and free PSA in early detection. The study was performed on all the new cases recorded by the National Cancer Registry (Registre Morphologique des Tumeurs). Total and free PSA were measured with the automated Immulite System (DPC, Los Angeles) using a chemoluminescent immunometric assay. The performance of free-to-total serum PSA was analysed by a hospital based study of 113 patients (55 PC, 58 BPH). The age standardized incidence rate increased from 29.3/100,000 in 1983 to 71.5/100,000 in 1995. Mortality rates only changed slightly. The widespread use of PSA testing from 1988 on is probably the main cause of this incidental increase; however no major changes in the age-specific-incidence have been found suggesting the absence of a systematic screening policy by the PSA. The superiority of free-to-total serum PSA ratio in discriminating between cancer and benign condition was confirmed. Early health-conscious man over 50 should be proposed prostate cancer screening by digital rectal examination and PSA. However a systematic screening policy cannot been recommended since a benefit in survival after early treatment has not yet been proven.

Adult↗
PubMed1997

High frequency of neoplasia in patients with autoantibodies to centromere protein CENP-F.

OBJECTIVE: To study the clinical features of patients with autoantibodies to centromere protein CENP-F and the frequency of CENP-F autoantibodies in patients with various diseases. DESIGN: Retrospective clinical and serologic study. METHODS: Thirty-six patients with anti-CENP-F were identified by a characteristic pattern of indirect immunofluorescence (IIF) on HEp-2 cells. Fifty patients with melanoma, 50 with breast cancer, 10 with lung cancer, 354 with systemic sclerosis, 120 with systemic lupus erythematosus and 50 with rheumatoid arthritis were also studied. Recombinant proteins were produced from 5 CENP-F cDNA clones representing amino acids 2192-3317 (p-F1), 5561-7126 (p-F2), 5892-6883 (p-F3), 7538-10,116 (p-F4) and 9242-10,096 (p-F5). The presence of CENP-F antigen was studied in a breast carcinoma cell line, cryosections of breast carcinoma, normal breast tissue and tonsils. RESULTS: Twenty-two of 36 patients with CENP-F antibodies had neoplasms; breast (9/22) and lung (5/22) cancer were the most common diagnoses. Thirty-three sera were available for further study; when tested for reactivity to the recombinant peptides, the sera of 21 of 21 patients with neoplasms and 5 of 12 patients with other diseases bound the C-terminal p-F4 peptide. When the terminal third of the p-F4 peptide (p-F5) was studied, a significant difference in pattern of reactivity was not detected. By comparison, the frequency of reactivity with peptides representing other domains of CENP-F was less than that with p-F4 (p-F2 > p-F3 > p-F1). CENP-F autoantibodies were not found in any of the control sera from patients with systemic lupus erythematosus, rheumatoid arthritis or systemic sclerosis or in unselected sera from various malignancies. CENP-F antigens were identified in breast carcinoma tissue but were rarely observed in normal tissues. CONCLUSIONS: A high proportion of individuals with CENP-F antibodies have neoplasia, and there is a bias among their sera for reactivity with determinants in the carboxy terminal domain of CENP-F. CENP-F antigens appear to be highly expressed in malignant tissues.

Adult↗
PubMed1997

[The neuropathies of IgM monoclonal gammopathies].

A peripheral polyneuropathy is often associated with an IgM monoclonal gammapathy. The monoclonal protein often binds to carbohydrate epitopes on glycoproteins and/or glycolipids of the human peripheral nerve. The clinical syndrome is related to the antigen-specificity of the IgM protein. Detection of anti-myelin antibodies and further characterization of their immunogenic specificity provide an important aid in the differential diagnosis of late-onset chronic polyneuropathies.

Glycolipids↗
PubMed1995

Autoimmunity to the cell cycle-dependent centromere protein p330d/CENP-F in disorders associated with cell proliferation.

p330d/CENP-F is a novel proliferation-associated and cell cycle-dependent centromere autoantigen which appears to play a very important role in mitotic progression. As an initial step in exploring the clinical and biological significance of autoantibodies to this protein, we evaluated the clinical histories of 26 patients producing these antibodies. The antibodies were detected by both indirect immunofluorescence microscopy (IIF) and Western blotting. All the sera contained anti-p330d/CENP-F IgG antibodies, with an average titer by IIF of 1:6,917 (range 1:160 to 1:20,480). Most of the patients had disorders associated with abnormal or increased cell proliferation at the time the anti-p330d/CENP-F antibodies were detected. These included cancers of various types (14), chronic liver disease (3), chronic rejection of renal allografts (2), and Crohn's disease (1). The average IIF titer of the anti-p330d/CENP-F antibodies in the patients with cancer, 1:10,103, was significantly higher than the average titer in non-cancer patients, 1:3,200 (P = 0.008). Autoimmunity to p330d/CENP-F appeared not to be associated with rheumatic diseases, in particular scleroderma, since only three of the 26 patients had rheumatic disease and the antibodies were not detected by IIF in a group of 351 patients with scleroderma and related disorders. Our findings, although retrospective and limited to a relatively small number of patients, point to the hypothesis that autoimmunity to p330d/CENP-F could be related to events involving increased or abnormal cell proliferation.

Adult↗