Osteo-articular manifestations of amyloidosis.

Whether it is overload disease or mispleated proteins, amyloid is a great pretender. This is especially true for all of the osteo-articular manifestations of amyloid light chain (AL) amyloidosis, which may mimic rheumatoid arthritis, polymyalgia rheumatica, a myeloma or a bone tumour. To improve the prognosis, AL amyloidosis must be considered in front of atypical osteo-articular manifestations. Amyloidosis Ab2M of chronic haemodialysis (members' arthropathy and destructive spondylitis) is a specific entity that needs to be differentiated from other osteoarthropathies of chronic renal failure. It has become exceptional since the progress of haemodialysis. Finally transthyretin amyloidosis(ATTR) can be responsible for carpal tunnel syndrome(CTS) in its genetic and senile form. Although amyloidosis is rare, it represents one of the aetiologies of CSC, regardless of its type. In the specific context of haemodialysis, this poses no difficulty for the clinician. Yet AL amyloidosis must be considered more often, as must senile amyloidosis ATTR in the elderly. It seems obvious that the anatomo-pathologic analysis with specific staining with Congo red - see typing - should be systematically performed in the case of surgical neurolysis. Amyloidosis is defined by the extracellular deposit of proteins which share common tinctorial affinities, a fibril aspect under electron microscopy and spatial conformation called beta pleated. Once regarded as a mere overload disease, it is currently considered as a disease of misfolded proteins. Indeed, it is certain that abnormalities of spatial pattern play an essential role in the responsibility for the pathology of many proteins whose amyloid fibre is the final common way. They involve both changes in the conformation of proteins and other major in vivo interactions between amyloid protein and the extracellular matrix. In most cases, amyloidosis represents the bulk of histopathological lesions and its pathogenic role is certain. In other cases, it is only one elementary lesion of the disease and its role is controversial. The amyloidosis responsible for osteo-articular manifestations are the AL immunoglobulin amyloidosis, the beta2-microglobulin amyloidosis in patients under haemodialysis and finally the amyloidosis of transthyretin (genetic and senile). Rheumatological manifestations of immunoglobulin amyloidosis are numerous and often indicative of the disease. Deposits affect joint and periarticular structures. The most common presentation is a progressively developing bilateral symmetric polyarthritis with negative immunology and absent specific structural abnormalities. Carpal tunnel syndrome (CTS) is very common and should suggest the aetiology. Other clinical representations are rarer as an isolated bone tumour (amyloidoma) or integrating systemic AL amyloidosis. ß 2-Microglobulin amyloidosis occurs in patients under chronic haemodialysis. It is responsible for CTS, arthralgia and above all a specific destructive spondyloarthropathy. The transthyretin amyloidosis also causes CTS.

High titers of autoantibodies in patients with sickle-cell disease.

OBJECTIVE: Frequency and titers of autoantibodies in patients with sickle-cell disease (SCD) have been reported as relatively high. In a prospective study of 88 patients, we examined this "hyper-autoreactivity" and its clinical consequences. METHODS: For 1 year, patients with SCD were screened for the presence in their serum of antinuclear, anti-double-stranded DNA, antiextractible nuclear antigens, anticardiolipin antibodies, and rheumatoid factors. A population of 85 sex-matched individuals of similar ethnic origin served as controls. RESULTS: Whereas prevalence of autoantibodies did not differ between the 2 groups, the type and rate of antinuclear antibodies were different. Autoantibodies from the SCD patients showed various immunofluorescence patterns, whereas only speckled patterns at low titers were present in controls. No antibody specificity was found in either group. SCD patients and controls displayed similar rates of anticardiolipin antibodies, but the SCD patients tended to be more frequently positive for rheumatoid factors. Six-year followup of the SCD patients did not provide any clinical evidence for onset of an autoimmune disease, except for 1 patient who developed rheumatoid arthritis, with increasing antinuclear antibodies followed by emergence of specific markers 5 years later. CONCLUSION: Patients with SCD displayed high titers of autoantibodies. This observation may be due only to immune activation and/or dysfunction in SCD, as neither pathogenic specificity of autoantibodies nor autoimmune clinical signs appeared in the majority of cases in our study.

Is sarcoma a complication of arterial femoro-popliteal bypass?

Angiosarcoma is a rare neoplasm comprising 1 to 2% of soft tissue sarcoma. This tumor has been associated with previous irradiation, exposure to toxins and the presence of foreign bodies. A case report of an epithelioid angiosarcoma that developed at the site of an arterial femoro-popliteal bypass using autologous vein is described. The initial presentation looked like a painful popliteal cyst. Chronic fibrosis secondary to the thrombosis could play a role in the tumorogenesis of this uncommon tumor. This case illustrates that sarcoma may be a late complication of vascular bypass and may have a rheumatologic presentation.

Tenosynovitis as a possible feature of immune reconstitution syndrome during highly active antiretroviral treatment (HAART).

An immune reconstitution syndrome (IRS) occurs in between 10% and 25% of patients starting highly active antiretroviral treatment (HAART). A 49-year-old patient presents a tenosynovitis 6 weeks after HAART initiation. In our patient, exhaustive tests for infectious, inflammatory and drug-related causes of tenosynovitis were negative. The improvement obtained with high-dose Non-steroidal anti-inflammatory-drug (NSAID) therapy and the patient's immunovirologic profile, supported a diagnosis of tenosynovitis associated with immune reconstitution, a form of IRS that has not previously been described. This original case increase the broad spectrum of inflammatory rheumatologic disorders associated with HIV infection.

[Osteo-articular complications of sickle-cell-anemia in adult]. / Complications ostéo-articulaires de la drépanocytose chez l'adulte.

Osteo-articular complications of sickle cell anaemia in adult are represented by bone marrow infarcts, osteomyelitis and osteonecrosis of femoral and humeral heads. The frequency and/or the severity of these complications provide a great functional disability in young patients whose life expectancy is growing. A well adapted treatment would may limit the sequels.