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Biomedical subjects

Y Maugars

Publications and source records attributed to Y Maugars.

At least 19 recordsLinked to original sources

Rheumatoid arthritis as a bone marrow disorder.

Both the concept of rheumatoid arthritis (RA) as an autoimmune process restricted to joints and the major role of T cells in its pathogenesis have been challenged in the literature. Fibroblastlike and macrophagelike synoviocytes play an important role in RA pannus, and these cells originate in or have their counterpart in bone marrow (BM). Yet the B cell autoimmunity characteristic of RA occurs early, and synovial tissue, like BM, favors the B cell response. Because BM is abnormal in RA, and because germinal centers are unique to RA synovium, RA could be regarded as a disorder of the microenvironments able to sustain B cell response. In fact, RA could even begin in BM, with its onset facilitated by stem cell abnormalities. Moreover, most viruses suspected of playing a role in RA share a BM tropism. This may explain why RA frequently overlaps with other autoimmune disorders and benign lymphoproliferations, such as large granular T lymphocytosis. Because remissions from RA have been reported after BM transplantation, careful studies of the rheumatological outcome of RA patients undergoing such therapeutic procedures are needed. Although RA is a complex process, it can be considered initially as a stem cell disorder requiring treatment similar to that administered to transplant patients. Animal models have provided convincing evidence for these assumptions.

Animals

Assessment of the efficacy of sacroiliac corticosteroid injections in spondylarthropathies: a double-blind study.

Despite previously carrying out a first open study of sacroiliac injection of long-acting corticosteroid, it was not possible to evaluate the role of a placebo effect. We therefore performed a double-blind study in 10 patients/13 articulations, suffering painful sacroiliitis. At 1 month, 5/6 sacroiliac joints injected with corticosteroid described a relief of > 70%, in comparison to 0/7 of the placebo group (P < 0.05). Dolometry showed a marked decrease in the corticosteroid group from (mean +/- S.E.M.) 6.8 +/- 0.6 to 1.3 +/- 0.3, and decreases were mild in the placebo group: 7.0 +/- 0.6 to 5.2 +/- 0.5 (P < 0.005). Six of the seven sacroiliac joints of the placebo group and two patients with failure and relapse of the corticosteroid group were reinjected with corticosteroid. At 1 month, 12/14 (85.7%) were assessed as having a good result. Results were still significant at 3 months (62%) and 6 months (58%). Tolerance was good or very good in 86% of the cases, and we did not report any notable complication. This technique is safe and very efficient, and it has to be considered more widely in patients with contraindications or complications with NSAID, or if the medical treatment is unable to control sufficiently the active sacroiliitis.

Adrenal Cortex Hormones

Osteoporotic fractures revealing anorexia nervosa in five females.

Anorexia nervosa affects 0.5% to 1% of female adolescents. The course is chronic in 50% of cases, causing substantial bone loss with osteoporotic fractures after a few years of amenorrhea. This is probably an underestimated problem. The diagnosis of anorexia nervosa is readily missed, as illustrated by five cases reported herein. The five patients were females aged 17 to 44 years who were only slightly underweight (mean weight, 43.6 kg; body mass index < 20 kg/m2). The first fracture occurred seven to 24 years after the onset of anorexia nervosa. Three patients had vertebral crush fractures, and two had peripheral insufficiency fractures. Bone mineral density measured by absorptiometry was very low (mean lumbar z-score, -3.7 SD). Three patients, who were all members of health care professions, knew that they had anorexia nervosa but failed to report this condition. In the other two patients, the amenorrhea had been mistakenly ascribed to other causes (Stein-Leventhal syndrome and psychogenic anovulation). None of the patients was receiving medical follow-up. Anorexia nervosa should be considered routinely in women who are slightly underweight. The patients often deny abnormal menstruation or eating behaviors. The diagnosis rests on determination of the body mass index, a thorough history emphasizing current and past gonadal dysfunction, and evaluation of the diagnostic criteria for anorexia nervosa. Osteoporosis is probably a common but underestimated complication of anorexia nervosa, particularly before the menopause. Enhanced awareness of this condition should allow earlier detection of a greater number of cases.

Absorptiometry, Photon

Myositis ossificans circumscripta with spontaneous healing of a cortical cyst.

We report a case of myositis ossificans circumscripta with an initial periosteal reaction and subsequent development of a cyst in the underlying cortex. All the roentgenographic abnormalities resolved spontaneously and permanently. The unusual course may have been due to formation of a subperiosteal hematoma at the time of development of the soft tissue ossification.

Adult

[Magnetic resonance imaging for lumbar disk pathology. incidence of false negatives].

Magnetic resonance imaging (MRI) has had an impressive impact on evaluation of degenerative diseases of the spine. Nevertheless, false negatives can occur on images involving lumbar discs. Degenerative disc diseases documented on discrography and/or pathology examination of the discs can go unrecognized. Likewise sensitivity for the detection of protruding discal hernias is not totally satisfactory (20% false negatives). Finally, a magnetic resonance image visualizing displacement of the disc is not specific (10 to 15% false positives); images showing protrusion or hernia can be seen in 30% of asymptomatic patients. Although MRI gives slightly more information than other imaging techniques, false images do exist. Moreover, the usefulness of MRI to demonstrate disc disease in case of a negative CT-scan remains to be demonstrated.

Diagnostic Errors

[Sports, bones and hormones. Multiple interactions].

Classically, sports activities are thought to have a beneficial effect on bone tissues. Actually, there are many interactions between sports activities and bone tissue and in certain cases complex hormone disorders may develop. Recent progress in the evaluation of bone structure (absorptiometry) and better understanding of the neuroendocrine functions have improved our knowledge of these interactions and helped provide answers as to the true effect of sports, and particular high-level training, on bone tissue. Mechanical stimulation of bone increases the level of both cortical and cancellous bone formation. The mechanical effect is localized in areas under particular constraint such as the lower limbs in runners and the upper predominant limb in tennis players. Inversely, hypoestrogenism, similar to anorexia nervosa, has been observed to be the cause of general bone loss and increased risk of osteoporosis in certain high level athletes. When these two opposing phenomena occur simultaneously, there is generally an overall loss of cancellous bone mass while bones submitted to major mechanical stress may be relatively protected. Amenorrhoea, particularly in long distance runners, generally occurs when training exceeds 30 km per week. Menarche may be delayed by 1 or 2 years when training begins early and dismenorrhoea is seen in 50% or more of the athletes. Amenorrhoea results from a central disorder due to insufficient pulsatile secretion of luteo-releasing hormone and subsequent hypogonadism. The role of beta-endorphins or catelestrogens on hypothalamic receptors has been suggested as the underlying mechanism. These different observations help provide answers to the different problems raised when providing counselling and care for high level athletes.

Amenorrhea

Dorsal scalloping by calcified disc herniation.

SUMMARY OF BACKGROUND DATA: Disc herniation responsible for scalloping of vertebral body had been reported only at the lumbar level. RESULTS: The authors report on an unusual etiology of dorsal scalloping. A voluminous and calcified dorsal disc herniation was responsible for this, and within the center of the mass there was an unexpected hypersignal on nuclear magnetic resonance imaging. CONCLUSION: Scalloping does not preclude disc herniation, even at the dorsal level. Hyperintensity in T1-weighted images can reveal calcifications, as indicated in previous studies.

Calcinosis

Specificity of antiperinuclear factor for rheumatoid arthritis in rheumatoid factor-positive sera.

Although antiperinuclear factor (APF) has the same specificity for rheumatoid arthritis (RA) as rheumatoid factor (RF), there is no evidence that this specificity is maintained in patients with positive RF-agglutination tests. Thus, we evaluated the specificity and usefulness of APF for RA diagnosis, regardless of RF titre. APF was tested (1:100 threshold) on 214 sera sent for RF evaluation over a 9-month period. These sera were previously determined to have latex or Rose-Waaler (RW) titres > or = 12 or 4 IU, respectively, but not necessarily above the threshold values of 100 and 32 IU. The APF test was performed blindly, and physicians were not advised of the results. In the patient population (119 RA and 95 non-RA) APF still demonstrated good specificity (0.82) for RA. As expected, APF proved useful for RA diagnosis in 28/33 (85%) RA cases with an RF level below 1:100 for latex and 1:32 for RW, thus reducing the number of 'seronegative' RA from 33/119 to 5/119. However, it also improved the serological positive predictive value for RA, even in cases when RW results were > or = 32 IU. Indeed, the positive predictive value for RA when both tests were positive was 0.94 (68/72), whereas concordant results (either positive or negative) for both APF and RW tests allowed correct classification (RA or non-RA) in 94% of cases.

Antibodies, Antinuclear

Rheumatoid arthritis and filaggrin. A review.

The most specific markers for rheumatoid arthritis are antibodies to keratinized epithelia, namely antiperinuclear factor, whose antigen target in human oral mucosal cells has exactly the same distribution as profilaggrin, and anti-rat esophagus antibodies directed against human filaggrin. In this review, we will discuss the large body of data on the nature and physiology of profilaggrin and filaggrin that has accumulated since the profilaggrin gene was cloned. The possible mechanisms and significance of loss of B-cell tolerance to filaggrin in patients with rheumatoid arthritis are examined.

Animals

Outcomes of thirty-four rheumatoid arthritis patients with renal amyloidosis, including twelve given alkylating agents.

We reviewed 34 cases of rheumatoid arthritis with biopsy-proven renal amyloidosis. Mean age was 57.1 +/- 13 years and mean duration of rheumatoid arthritis was 13.7 +/- 8.2 years. Renal function tests done at the time of diagnosis of amyloidosis were available for 32 patients and showed renal failure in 16. Twelve patients received an alkylating agent. Twenty patients (59%) died, after a mean interval of 25.7 +/- 25.1 months since the diagnosis of renal amyloidosis; 19 of these patients (95%) had renal failure. Seven of the 14 survivors and four of the 11 survivors with impaired renal function were given an alkylating agent; mean follow-up since the diagnosis of renal amyloidosis was 77.2 +/- 58.7 months. At completion of the study, renal function was normal in only three patients, all of whom received an alkylating agent. Our data confirms the bleak prognosis of renal amyloidosis in rheumatoid arthritis patients and suggests a need for randomized trials designed to evaluate the efficacy of alkylating agents in this condition.

Adult

[Dual-energy X-ray absorptiometry: value in orthopedics].

We emphasize the opportunity of an in vivo bone mass measurement with an easy and accurate technique for orthopedic practice. At the present time, Dual Energy X Ray Absorptiometry (DEXA) is the most used technique, and is a safe and short examination. It can assess the quantity of mineral of any region of the body with a remarkable reproducibility (1 to 3 per cent). New machines are improved, and they permit many practical applications beyond the osteoporosis field. Thus, in orthopedics, we can distinguish several interesting topics. Peripheral risk of fracture can be evaluated because of good correlation between bone mineral content and biomechanical properties of bone. Even if a peripheral fracture occurs after a fall, low bone mineral density plays an important role, as in the case of femoral neck fractures in elderly patients. In traumatological practice, a DEXA with a specialized advice has to be requested if the traumatism cannot fully explain the occurrence of the peripheral fracture. Low bone mineral density defines an osteoporotic state, with the possibility of selecting adequate therapy. The good reproducibility of the measurement allows early estimation of bone loss following a period of immobilization. Varying models of osteosynthesis can be compared in vivo, to evaluate a decrease of "stress shielding" bone resorption. The role of stiffness of an implant on regional bone mineral content can be assessed. Likewise, periprosthetic bone mineral content can be measured in various regions, and followed over time. Specific software allows the exclusion of the region where the metallic prosthesis is projected. The reproducibility of this peripheral bone mineral content is 2 to 3 per cent, which individually allows an estimation of variations of more than 5 per cent. It will be possible to evaluate in vivo the influence of various parameters of the prosthesis on bone mineral content in controlled studies, such as the role of the shape, the position, the structure, the coating. Mineral content of biomaterials and bone grafts are taken into account. Focusing the X Ray beam allows ultrahigh resolution. Precise measurements of very small parts of bone such as rodent tibia or vertebra are possible. The good reproducibility (2 per cent) authorizes the evaluation of various parameters which modify bone remodeling, such as immobilization or activity, ovariectomy. Preventive or curative therapeutics which change bone mass can be evaluated in animal pre clinical studies. There are other methods of measurement of bone mineral content. Digitalization of radiographs is not sufficiently accurate and CT Scan generate high levels of radiation. The DEXA is actually the best compromise for an accurate and reproducible measurement of the bone mineral content in vivo. This method will certainly be an important tool in orthopedics for several clinical or animal investigations in the future.

Absorptiometry, Photon

SAPHO syndrome: a followup study of 19 cases with special emphasis on enthesis involvement.

OBJECTIVE: To study the natural history, prognosis, and nosology of synovitis, acne, pustulosis, hyperostosis, osteitis (SAPHO) syndrome. METHODS: We performed clinical, radiological, and biological reassessment of 19 cases of SAPHO syndrome (13 with pustulosis palmaris et plantaris, 3 with acne, 3 with no dermatological manifestations) after a mean disease course of 12.3 yrs (1-35). RESULTS: Similar involvement was noted in all patient groups. Despite persistent remittent attacks in 11/19 cases and new localizations in 10/19, the prognosis is promising and 18/19 patients considered that improvement has occurred. Enthesis involvement, occasionally associated with osteolysis, was in most cases the first event leading to hyperostosis, but tended to disappear in the spine and peripheral joints once synostosis was achieved. The behavior of osteochondral cartilage was similar to that of the enthesis, whereas the ribs below T6 were spared. We report the first descriptions of hyperostosis of the first costotransversal joint, interspinal ossification, erosion of wrist bones, followed by synostosis, and formation of bony bridges between ribs. CONCLUSION: SAPHO syndrome appears to be a relevant disease process with good prognosis. Although aseptic osteitis is regarded as the hallmark of this entity, our followup study strongly suggests that the initial disease targets are enthesis and related tissues. Forty-three percent of our patients met criteria of the European Spondyloarthropathy Study Group for spondyloarthropathy, but only one had the HLA-B27 phenotype. Thus, it may be considered that SAPHO syndrome is nosologically related to spondyloarthropathy, especially those types associated with psoriasis, but probably differs in pathogenesis.

Acne Vulgaris

Autosomal dominant Muckle-Wells syndrome associated with cystinuria, ichthyosis, and aphthosis in a four-generation family.

Muckle-Wells syndrome is a rare autosomal dominant disorder characterized by chronic recurrent urticaria, periodic arthritis, sensorineural deafness, general signs of inflammation, and secondary amyloidosis (AA type). We report on a 4-generation family with 7 persons sharing various signs of this syndrome associated with bipolar aphthosis in 5 cases and cystinuria in one. Two other relatives in the family had ichthyosis.

Adolescent

[Osteoporosis in anorexia nervosa].

Bone loss in subjects with anorexia nevrosa was first demonstrated in 1984 and later confirmed by computed tomography and absorptiometry. Both cortical and trabecular bone is involved. Bone mineral content decreases early and has been estimated at 6 to 8% in 90% of the subjects with anorexia nevrosa. It is correlated with age and the duration of the anorexia and the associated amenorrhoea. Other factors including low weight, early onset, primary amenorrhoea, low serum oestradiol and high serum cortisol are also observed. In severe cases, fractures, similar to those observed in post-menopause osteoporosis, include vertebral wedge fractures, fractures of the ribs, the femoral neck, the forearm and the pelvis. In subjects with long-standing anorexia nevrosa, fractures often occur without weight loss and the diagnosis may be missed. A careful work-up is needed in all cases of bone loss in young women. The osteoporotic process is reversible in most cases if the anorexia can be overcome. Bone mineral content in cured subjects has been shown to be the same as in age-matched controls, but in severe long-term cases, relapse and chronicity lead to continued bone loss. Normal menarche can generally be established with oestrogen therapy although significant gains in bone mineral content does not always follow. When progesterone-oestrogen therapy is combined with small dose fluorine (11.5 mg/day) bone mineral content has been shown to improve. Many subjects however refuse medication, especially oral contraceptives, hindering psychiatric care which should always have first priority. The mechanism of bone loss in anorexia nevrosa is similar to that in post-menopause osteoporosis but may be favoured by other factors including alcohol intake and drug abuse. Certain authors have also hypothesized a common mechanism relating the amenorhoea observed in women training for high performance sports and that in anorexia nevrosa. In clinical practice, first intention treatment should rely on hormone replacement but medication is often refused and can interfere with necessary psychiatric treatment. Sports appear to have a beneficial effect on femoral neck mineralization but in hyperactive subjects the effect is often inversed with increased bone loss. Patent osteoporosis can be treated with fluorine and biphosphonate.

Adolescent

[Palindromic rheumatism disclosing Whipple's disease. Study of 2 personal cases].

Two patients with palindromic rheumatism were diagnosed with Whipple's disease 5 years after onset of the joint symptoms. Twenty-one previously published cases of Whipple's disease with palindromic rheumatism as the first manifestation were identified. Statistically significant differences were found between palindromic rheumatism in patients with and without Whipple's disease. Patients with Whipple's disease were more likely to be male and to exhibit fever and elevated erythrocyte sedimentation rates during joint symptom flares, whereas they were less likely to have involvement of the metacarpophalangeal and proximal interphalangeal joints. None of the patients with Whipple's disease had either skin manifestations of palindromic rheumatism (nodules or paraarthritis) or positive tests for rheumatoid factor. Patients with palindromic rheumatism exhibiting these features should have an intestinal biopsy to look for Whipple's disease.

Arthritis, Rheumatoid