[Pathophysiology of cholesteatoma]. / La physiopathogénie des cholestéatomes.

OBJECTIVE: To describe the development of cholesteatoma using current knowledge. METHOD: Review of the literature. RESULTS: Cholesteatoma describes a mass of keratin (skin) in the middle ear which consists of a perimatrix and matrix. There are at least three kinds of cholesteatoma in the middle ear one resulting from invagination (retraction's pocket), another from migration and the last one from congenital inclusion. Cholesteatoma needs three successive inflammatory phases, the first leading to a retraction pocket, the second leading to pathology of the epidermis and of the floor of the external auditory canal and the third is the actual phase of cholesteatoma with invasion and middle ear auto-destruction with bone resorption. In this last phase, many factors play a role, collagenasis, osteoclats, cytokines, NO, bacteria and their biofilm and rupture of the retraction pocket. CONCLUSION: Cholesteatoma is an inflammatory disease of the ear caracterised by bone resorption. Current research is starting to appreciate the important role the immune system plays in the pathophysiology of cholesteatoma.

Use of whole Streptococcus pneumoniae cells as a solid phase sorbent for C-reactive protein measurement by ELISA.

Monolayers of pneumococcus (serotype 27) on flat bottom polystyrene microtiter plates were used as a solid phase sorbent for the determination of C-reactive protein (CRP) by ELISA. After binding to the monolayer, CRP was quantified with peroxidase conjugated rabbit anti-human CRP immunoglobulin. The method is sensitive (5 micrograms/ml), rapid (less than 2 h) and correlates well with a laser nephelometric assay (r = 0.95, P less than 0.001), and with a classical sandwich ELISA (r = 0.95, P less than 0.001).

ELISA using whole Legionella pneumophila cell as antigen. Comparison between monovalent and polyvalent antigens for the serodiagnosis of human legionellosis.

An indirect enzyme-linked immunosorbent assay (ELISA) using the six serogroups of whole L. pneumophila bound to microtitre plate wells is described for the serodiagnosis of legionellosis. Comparative studies using monovalent antigen indicated a high correlation between ELISA and indirect immunofluorescence antibody (IFA) tests (r = 0.90, P less than 0.001). Testing 196 human sera by ELISA using both monovalent and polyvalent antigens have established the efficiency of the polyvalent antigen for screening purposes. The ELISA test system exhibited rapidity, sensitivity and reproducibility and should be considered as an alternative to the IFA test for routine serodiagnosis of legionellosis.

Preformed antibody and complement rebound after plasma exchange: analysis of immunoglobulin isotypes and effect of splenectomy.

UNLABELLED: Splenectomy (Sx) has been proposed to attenuate post-PE (plasma exchange) rebound of isoagglutinins and xenogenic (XG) antibody (Ab) in both ABO-incompatible allografts and discordant xenografts. This study analyses the qualitative nature and kinetics of serum immunoglobulins as well as complement resynthesis after PE in sham-operated (PE) and splenectomized (PE+Sx) syngeneic LOU/C rats; non-PE sham-operated or splenectomized animals were used as controls. PE was performed in unanesthetized, unheparinized rats. Immunoglobulin isotypes and subclasses (IgM, IgG1, IgG2 alpha, IgG2b) of total circulating Ab were measured pre-PE and up to 21 days post-PE, using ELISA (enzyme-linked immunosorbent assay) and specific mouse antirat monoclonal Ab. Antiguinea-pig (GP) XG Ab (IgM, IgG2a) serum levels were measured using cellular ELISA with cultured GP endothelial cells as targets. Sx alone significantly reduced XG IgM serum levels (p < 0.0001). Maximal rebound of total and XG IgM was observed on day 3 post-PE, reaching 674% and 187% of the pre-PE levels, respectively; these overshoots were entirely suppressed by Sx (p < 0.005 for total IgM; p < 0.0001 for XG IgM). Total IgG2a, IgG2b and IgG1 as well as XG IgG2a serum levels did not show significant overshoot post-PE. The activity of the complement classical pathway (mean +/- SD), assessed by CH50, was decreased at 51 +/- 19% of basal value 15 minutes after PE, and had returned to baseline level by day 2 post-PE with or without Sx. IN CONCLUSION: (1) Six alone significantly reduced XG IgM serum levels; (2) early post-PE Ab rebound was mainly observed for IgM; (3) both total and XG IgM rebound was inhibited by Sx. This suggests that Sx probably removes a significant proportion of IgM producing cells undergoing post-PE stimulation. These data provide a rationale for combining PE with Sx in ABO-incompatible and discordant XG transplantation.

Clinical and serological studies in a series of 45 patients with Guillain-Barré syndrome.

We retrospectively reviewed the clinical files of 45 Guillain-Barré syndrome (GBS) patients admitted to our Department between 1979 and 1989. The age distribution was bimodal with a first peak in young adults (20-40 years), and a second one between 60 to 70 years. Seasonal distribution showed a late fall and a hivernal predominance. Three patients experienced a second attack of GBS 2-9 years after the first one. Thirty-one (69%) presented antecedent events, most often a respiratory tract infection (n = 20) or enteritis (n = 6). Serological studies were systematically performed, including antibody titers against herpes simplex virus, Epstein-Barr virus, cytomegalovirus (CMV), respiratory syncytial virus, human immunodeficiency virus, Mycoplasma pneumoniae, Campylobacter jejuni/coli and cardiolipin. These studies showed the presence of antibodies indicative of a CMV primary infection in 22% cases and of a Campylobacter jejuni/coli infection in 13%. Co-infection was observed in 3 cases. Serology remained negative in 12 patients with a preceding respiratory infection. There was no correlation between serology and the severity of the disease. Absence of antecedent events and of positive anti-infectious serology was observed in only 10 patients.

No evidence of auditory dysfunction in guinea pigs immunized with myelin P0 protein.

Recent data have focused on the peripheral nerve myelin glycoprotein P0 as a putative autoantigen involved in the autoimmune etiology of some cases of Meniere's disease, idiopathic sensorineural hearing loss and sudden deafness. To determine whether antibodies to myelin P0 can alter cochlear function, 13 healthy guinea pigs were immunized with purified porcine myelin P0 while 10 controls were injected with saline water. The animals were then evaluated for evidence of evolving inner ear disease using immunological, electrophysiological and morphological methods. Twenty-six experimental ears were tested weekly with a brainstem auditory evoked potential technique for a period of 4 months and were compared to 20 control ears. Uniformly, all P0-sensitized guinea pigs showed antibodies to myelin protein P0 as evidenced by ELISA. Clinical signs of inflammatory demyelination were not discernible in P0-sensitized guinea pigs and all the animals were qualitatively normal. No significant increase of evoked potential thresholds was found in the P0-sensitized animals when compared to controls (P>0.05). Peak latencies of waves I, II, III, IV and V and inter-peak latencies in P0-sensitized guinea pigs did not significantly differ from those of controls (P>0.05). Histological sections of inner ear and peripheral nerves were free of disease in both groups. These findings indicate that the sole presence of antibodies to myelin P0 in the sera of guinea pigs or patients suspected of having autoimmune inner ear diseases is unlikely to elicit auditory abnormalities and that additional factors are necessary for the pathogenic development of these disorders.

Autoimmune sensorineural hearing loss in young patients: an exploratory study.

OBJECTIVES: P0 protein is expressed exclusively in myelinating Schwann cells of the peripheral nervous system. In a previous study from our laboratory, 27% of patients with sensorineural hearing loss (SNHL) had antibodies to P0 protein in their serum. The purpose of the present exploratory study was to examine the relationship between the clinical presentation of SNHL among children and young adults (age range, 5-30 y) and the presence of serum anti-P0 antibodies. STUDY DESIGN: The data were collected by retrospective questionnaires from Belgian otolaryngologists. METHODS: Patients were divided for comparison into two groups according to the presence or absence of anti-P0 antibodies. RESULTS: Analyses of clinical data and audiometric results indicated that a progressive hearing loss was more frequently recorded in the patients in the anti-P0 antibody-positive group (82% [14 of 17]) than in those in the anti-P0 antibody-negative group (35% [6 of 17]) (P <.005). CONCLUSIONS: Thus, in the age group in the present study, autoimmune SNHL (as measured in the present study by the presence of anti-P0 antibodies) is more frequently associated with progressive than with sudden hearing loss. The implications of this finding for preventive screening of hearing loss in children and young adults are discussed.

Guinea pig inner ear antigens: extraction and application to the study of human autoimmune inner ear disease.

In this study, the authors attempted to develop a method of extracting guinea pig inner ear antigens for otoimmunological research, and to investigate the distribution of the antigens in the various structures of the inner ear. The antigens were extracted either from the entire or from various parts of the guinea pig inner ear. These antigens were separated on sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) gels. Western blot techniques were used to test sera from patients with inner ear disease against guinea pig inner ear protein extracts. It found that the various molecular weight antigens in the inner ear were associated with the different structures of the inner ear. The sera of 37.5% (N = 80) of patients reacted with two bands (30 and 58 kd) of the guinea pig inner ear immunoblots. The 58 kd band was not specific to the inner ear, but instead was also found in the immunoblots of other guinea pig tissues (brain, lung, and liver). This study suggests that the various antigens of interest could be further extracted and purified from the corresponding locations of the inner ear.

Clinical significance of antiproteinase 3 antibody positivity in cANCA-positive patients.

We addressed the clinical significance of antiproteinase 3 (anti-PR3) antibody (Ab) positivity by reviewing the files of 79 patients whose serum contained antineutrophil cytoplasmic antibodies with a cytoplasmic staining pattern (cANCA) and had been tested for anti-PR3 reactivity. Vasculitis was present in most (22/35) cANCA+ PR3+ patients but in only a few (5/44) cANCA+ PR3- patients, thereby suggesting that anti-PR3 Ab positivity in cANCA+ patients is more indicative of vasculitis than cANCA positivity alone. Noteworthy, one-third of cANCA+ PR3+ patients -- those with anti-PR3 Ab titres lower than 100 U/ml -- did not suffer from vasculitis. Anti-PR3 reactivity in vasculitis patients was only weakly associated with Wegener's granulomatosis (WG), as nine out of 22 cANCA+ PR3+ vasculitis patients (41%) did not fulfil the ACR classification criteria for WG. There was no correlation between anti-PR3 Ab titres and disease activity at diagnosis. However, titres measured when patients were in remission were much lower than initial values. Taken together, our results indicate that anti-PR3 Ab positivity should be interpreted in its clinical context.

COCH5B2 is a target antigen of anti-inner ear antibodies in autoimmune inner ear diseases.

OBJECTIVE: This study was designed to identify the 58-kDa inner ear protein against which the sera of some patients with idiopathic, progressive sensorineural hearing loss or Ménière's disease strongly react. BACKGROUND: We and other groups have previously demonstrated that a 58-kDa protein extracted from guinea pig or bovine inner ear tissue is a target of antibodies in serum samples from some patients with autoimmune inner ear diseases. METHODS: After separation of inner ear proteins by 10% sodium dodecyl sulfate polyacrylamide gel electrophoresis, the bands corresponding to 58 kDa were localized and excised from the gel. The concentrated protein was then digested with trypsin, and the peptide fragments were separated by high-pressure liquid chromatography. Three fractions were subjected to amino acid sequencing by the classic Edman degradation. RESULTS: The sequence of a stretch of 14 amino acids of the first fragment was identical to that of amino acids 526 to 539 of the COCH5B2 protein. The sequences of 11 and 10 amino acids of the second and third fragments, respectively, also were identical to residues 417 to 427 and 396 to 405 of the COCH5B2 protein. These data, together with two-dimensional gel electrophoresis followed by Western blot experiments, confirmed that the 58-kDa inner ear protein is the COCH5B2 protein. DISCUSSION: These findings indicate that the 58-kDa target protein of antibodies in serum samples of patients with autoimmune inner ear diseases is the COCH5B2 protein, a molecule that is highly and specifically expressed in the cochlea and vestibule.

HLA class II-associated genetic susceptibility in idiopathic progressive sensorineural hearing loss.

To investigate the association between genes in the major histocompatibility complex and inner ear disease susceptibility at the DNA level, high-resolution genotyping for HLA class II (HLA-DR, -DQ, -DP) was performed by polymerase chain reaction-sequence-specific oligonucleotide reverse dot blot and polymerase chain reaction-restriction fragment length polymorphism analysis in 34 patients with idiopathic progressive sensorineural hearing loss (PSHL) and in 214 controls. The frequencies of DRB1*0301, DRB3*0101, DQB1*0201, and DPB1*0401 were significantly increased in patients with idiopathic PSHL compared with controls. The DQB1*0301 allele was significantly decreased in the patients. A linkage disequilibrium was probably responsible for the concomitant increase of both DRB1*0301 and DRB3*0101 alleles in patients. The increase of DQB1*0201 in patients was associated with the DRB1*0301 allele. In addition, the telomeric DPB1*0401 allele may act as an independent risk factor. The DQB1*0301 allele may have a protective role in the pathogenesis of idiopathic PSHL. These results suggest that the specific HLA class II gene products may confer susceptibility or resistance to idiopathic PSHL.

Inner ear autoantibodies and their targets in patients with autoimmune inner ear diseases.

Immunological mechanisms are thought to play an important role in the pathogenesis of some cochleo-vestibular diseases. This study attempts to present further evidence of autoantibodies reactive against guinea pig inner ear proteins found in patients with autoimmune inner ear diseases (AIED) and specifically identifies the main target antigens of these antibodies. Sera from 110 patients with a clinical diagnosis of either rapidly progressive sensorineural hearing loss (n = 32). Ménière's disease (n = 41), sudden deafness (n = 6) or other aetiologies of hearing loss (n = 11) were screened by the Western blot technique. Forty-four percent of the patients' sera had antibodies to several inner ear proteins, of which the 30, 42 and 68 kDa proteins were found to be the most reactive. These highly reactive proteins were identified by gas-phase micro sequencing after digestion with trypsin and separation of peptide fragments by high-performance liquid chromatography. A partial sequence of each protein was determined. These data, together with those obtained from 2-dimensional gel electrophoresis followed by Western blotting, demonstrated that the 30 and 42 kDa inner ear proteins are the major peripheral myelin protein P0 and the beta-actin protein, respectively, while sequence analysis indicated that the 68 kDa protein is novel. These findings further support the hypothesis that several populations of antibodies may contribute to the enhanced immunological activity of AIED patients. They also add a new dimension to our knowledge of AIED and may open new avenues in the development of simple serological assays, which are easier to perform and more rapid than Western blotting.

The localization and specificity of guinea pig inner ear antigenic epitopes.

In this study, we investigated the relative localization of some antigenic epitopes in the inner ear. The inner ear protein antigens were extracted from various parts of the guinea pig inner ear. Brain, kidney, lung, heart and liver extracts were also obtained. We found by SDS-polyacrylamide gel electrophoresis that total inner ear extracts separated into three high concentration polypeptide bands with molecular weights of approximately 30, 42, 58 kd and three low density bands of 20, 25 and 35 kd. The 30 kd band was found mainly in the extract of the spiral ganglion and the acoustic nerve in the modiolus. The 42 and 58 kd bands were detected in the extract of the spiral ligament and the stria vascularis. The Organ of Corti and the basilar membrane extract gave rise to three bands of 30, 42 and 58 kd. Twenty-eight of the 75 sera from patients with inner ear disease reacted with the 30 and 58 kd bands of the inner ear protein extracts by immunoblotting. Sixteen of these 28 positive sera were then used to probe immunoblots of the brain, kidney, lung, heart and liver extracts. The 58 kd band was also found in protein extracts of the brain, the lung and the liver. This study suggests that the 30 kd antigenic epitope may be mainly related to the acoustic nerve and that the 58 kd antigenic epitope is not cochlear specific.

[Severe hepatitis with encephalopathy induced by acetylsalicylic acid in a case of lupus erythematosus disseminatus]. / Hépatite grave avec encéphalopathie imputable à l'acide acétylsalicylique dans un cas de lupus érythémateux disséminé.

The observation of a 62 year-old woman who had been suffering from arthritis for several years and in whom treatment with high doses of acetylsalicylic acid resulted in severe acute hepatitis is reported. Clinical and serological findings led to the diagnosis of systemic lupus erythematosus complicated by acute drug induced hepatitis.

[Rectal leiomyosarcoma. 4 new cases]. / Léiomyosarcome du rectum. Quatre nouvelles observations.

We report four cases of leiomyosarcoma of the rectum suspected by endoscopic ultrasonography. Three patients were treated by local excision and one by abdominoperineal resection. An excision of the mass via a Kraske's approach was used. Leiomyosarcoma confined to the rectum wall can be treated by local excision. Endosonography can provide exact estimation of the lesion and is of great value in selecting the appropriate treatment. The treatment is surgical excision with wide margins. The histological stage and the presence or absence of metastases determine the therapeutic. Two patients in our series underwent radiation therapy. Chemotherapeutic agents including doxorubicin have had beneficial effect on recurrence or survival, only for higher grade sarcomas.

[Combination of colorectal tumor and Streptococcus bovis endocarditis. Apropos of 3 cases]. / Association d'une tumeur colo-rectale et d'une endocardite à Streptococcus bovis. A propos de trois observations.

The authors report about 3 cases of bovis endocarditis revealing a colic carcinoma. This morbidity confirms the need for routine digestive investigations in endocarditis due to group D streptococci and eventually a liver disease.

[Digestive cancers and choroid metastasis. Diagnostic circumstances and prognostic value apropos of 2 cases]. / Cancers digestifs et métastases choroïdiennes. Circonstances du diagnostic et intérêt pronostique à propos de 2 observations.

We report two observations of malignant gastric and pancreatic tumors with choroid metastasis. Clinical course was rapidly and spontaneously unfavorable.

[Leiomyosarcoma of the inferior vena cava. Apropos of a new case]. / Léiomyosarcome de la veine cave inférieure. A propos d'une nouvelle observation.

A leiomyosarcoma was diagnosed in the mid portion of the inter-renal inferior vena cava. Survival was long (6 years) but required 14 reoperations to remove metastases. During the first operation, vascular integrity was reestablished with a cava-cava prosthesis after exeresis of the upstream cava without removal of the left renal vein ostium. The right renal vein was sectioned and directly implanted onto the prosthesis. The pathology report confirmed the diagnosis of leiomyosarcoma with multiple metastases presenting cytonuclear anomalies which worsened with time.

[Comments on emergency treatment of biliary lithiasis in patients over 75 years of age. Apropos of 157 cases]. / Réflexions sur le traitement des urgences de la maladie biliaire lithiasique chez les sujets de plus de 75 ans. A propos de 157 observations.

Surgery remains the ideal emergency treatment for biliary lithiasis in elderly subjects despite perioperative morbidity and mortality. Minimally invasive techniques appear promising but require assessment. The aim of this work was to determine the usefulness of these techniques and evaluate outcome in a series of 157 patients over 75 years of age who were hospitalized in an emergency setting of complicated biliary lithiasis from January 1990 to December 1996. There were 103 women and 54 men, mean age 82 years. The patients' general status was evaluated according to the ASA classification; 66% of the patients were ASA III, IV or V. Diagnoses at admission were acute cholecystitis (n = 71, 45%), angiocholitis (n = 50, 31%) subintrant hepatic colic (n = 17, 10.8%), pancreatitis (n = 10, 6%), isolated jaundice (n = 2), peritonitis (n = 2) and occlusion (n = 5). Within 24 hours of admission, 7 patients underwent emergency surgery, and the 150 others were given medical treatment. Among these 150 patients, cure was considered to have been achieved with medical treatment alone in 41 (subsequent surgery being required in only one 6 months later), semi-emergency was performed in 17, and a minimally invasive procedure was performed in the 92 others (echo-guided percutaneous cholecystostomy in 42, endoscopic sphincterotomy in 50) followed by a subsequent operation in 29. In the 103 patients (65.5%) in this series who did not undergo surgery, mortality was 3.8% and in the 54 patients (34.5%) who did, mortality was 15%, but this rate was only 6.9% when the open procedure followed a minimally invasive technique. Surgical treatment of complicated biliary disease remains the ideal therapy but indications should be carefully weighed in these elderly fragilized subjects. Under surgical observation, abstention from surgery or use of minimally invasive techniques can play an important role in the therapeutic strategy aimed at lowering perioperative mortality.

Belgian recommendations on ANA, anti-dsDNA and anti-ENA antibody testing.

Autoantibodies to nuclear antigens, i.e. antinuclear antibodies (ANA), antibodies to double-stranded DNA (dsDNA) and extractable nuclear antigens (ENA), are useful as diagnostic markers for a variety of autoimmune diseases. In March 2010, the Belgian national External Quality Assessment Scheme sent a questionnaire on ANA, anti-dsDNA and anti-ENA antibody testing designed by the Dutch EASI (European Autoimmunity Standardization Initiative) team, to all clinical laboratories performing ANA testing. Virtually all laboratories completed the questionnaire (97·7%, 127/130). This paper discusses the results of this questionnaire and provides valuable information on the state-of-the-art of ANA, anti-dsDNA and anti-ENA antibody testing as practiced in the Belgian laboratories. In addition, this work presents practical recommendations developed by the members of the advisory board of the scheme as a result of the outcome of this study.