Sarcomatous degeneration in Paget's bone disease.

The authors report 12 cases (8 men and 4 women) of sarcomatous degeneration in Paget's bone disease, with an average age of 72.3 years. Sarcomatous degeneration occurred often in polyostotic Paget's disease, and osteitis deformans was seen in 4 cases. Femur and pelvis were the most affected bones. Pain was a constant feature, whereas tumefaction and fracture were less common. Osteolytic lesions were more frequent than condensed or mixed lesions and radiological signs of malignancy were usually found. Seven cases were histologically classified as osteogenic sarcoma and 3 cases as fibrosarcoma. Electron microscopy was performed on 2 osteogenic sarcomas and in 1 case revealed microcylindrical inclusions in Pagetic osteoclasts and in multinucleated giant tumor cells, but none in mononucleated tumor cells. The average survival time for the patients in this study was only 4.5 months.

[The natural development of osteoporosis. 30 patients with a median follow-up of 11 years]. / Contribution à la connaissance de l'évolution naturelle de l'ostéoporose. 30 malades avec un recul moyen de 11 ans.

The authors present a sketch of the natural development of osteoporosis based on a retrospective study over a mean period of eleven years of 30 osteoporotic subjects (23 females, 7 males) who had received little or no treatment. Development was rapid during the three years following diagnosis, as was shown by the annual number of attacks of acute spinal pain, months of functional handicap and vertebral compression fractures, as well as by changes in size and the two vertebral radiologic indices used. Development slowed after the fourth year, but subsequent deterioration was unaffected. This spontaneous change seemed to depend less on etiological factors than on a decrease in bone mass to below the threshold at which fractures may develop. Slowed development of osteoporosis after the fourth year appeared to be due to an adaptation of the subject's way of life to the fragility of the spine. The results of treatment and monitoring of three years or less should be viewed in light of this slowed osteoporotic development.

[Serum concentrations of 1,25-dihydroxyvitamin D in cases of osteomalacia, parathyroid dysfunction and idiopathic hypercalciuria]. / Etude des concentrations sériques en 1,25-dihydroxyvitamine D dans des cas d'ostéomalacie, de dysfonctionnement parathyroïdien et d'hypercalciurie idiopathique.

1,25 dihydroxyvitamin D (1,25(OH)2 D) is the active metabolite of vitamin D and has an essential role in bony metabolism on the regulation of the calcium-phosphorus balance. The circulating level of 1,2(OH)2 D is normally between 25 and 45 pg/ml. Isolation of the fraction to be titrated requires sophisticated purification techniques using high performance chromatography (HPLC). In osteomalacia secondary to a deficiency the mean level of 1,25(OH)2 D is low (14.1 +/- 6.9 pg/ml) because of substratum deficiency. Administration of vitamin D supplements is quickly followed by a supraphysiological increase of the level of active metabolite. The role of the parathyroid hormone on the activity of 1-hydroxylase is illustrated by the results of the titration in parathyroid dysfunctions: decrease of the mean level in hypoparathyroidism (18 +/- 6.9 pg/ml), and on the contrary, a significant increase in hyperparathyroidism (56.6 +/- 15.4 pg/ml) despite of a spread of the individual values. In 18 cases of idiopathic hypercalciuria, we have only observed an increase of 1,25(OH)2 D level, in two cases. Titration of 1,25(OH)2 D complements the calcium-phosphorus evaluation to precise the physiopathogenic mechanism of the disorders observed in various diseases. Its interpretation requires the joint measurement of the substratum level, 25-hydroxyvitamin D, and the evaluation of the parathyroid function.

[Ankylosing panarthritis]. / La panarthrite engainante.

The authors report 4 cases of "Sheathing Panarthritis" (S.P.): two female patients with a positive rheumatoid serology, presented a complete ankylosis of the articular system, including the temporo-mandibular joint and the spine; two male patients presented a complete articular ankylosis of the lower extremities and a more or less total spine ankylosis, by only a slight involvement of the upper extremities. The study of the HLA system, carried out in ten cases--3 in this series--showed the presence of B27 in six cases, and the presence of A2 in five cases out of eight. A single study of locus DR revealed the presence of DR 1. On the nosological point of view, this radio-clinical picture, individualized by Forestier, was successively considered as an autonomous affection, a rheumatoid polyarthritis (P.R.), an ankylosing spondylarthritis (AS). The author's opinion is dual since, from the analysis of the cases, they do not feel that it is possible to classify all cases either with P.R. or with A.S. After studying the various radio-clinical aspects of P.R., they believe that, in patients with S.P., it exists an ankylosing "factor X" which exacerbates the ability of P.R. and A.S. to manufacture sclerosis, transforming these diseases into S.P.

[A case of very destructive dorsal spondylodiscopathy surgically treated in ankylosing spondylitis complicated by amyloidosis]. / Un cas de spondylodiscopathie dorsale très destructrice et traitée chirurgicalement au cours d'une spondylarthrite ankylosante compliquée d'une amyloïdose.

An ankylosing spondylarthritis was complicated by a D9-D10 spondylo-discopathy, with severe destructive alterations. After strict immobilization for three months, when the lesions partly regressed, non-steroid anti-inflammatory (NSAI) drugs were unable to cause a cure. An excellent result was obtained with a surgical arthrodesis after 5 years. The vertebral location was filed with fibrous tissue. The patient died from an amyloid disease with renal insufficiency. The presence of amyloid tissue in the vertebral location did not prevent a good healing of the vertebral arthrodesis.

[How to evaluate the activity of Paget's disease in clinical practice and which patients should be treated?]. / Comment évaluer, en pratique, l'activite de la maladie de Paget et quels malades traiter?

In patients with Paget's disease, the alkaline phosphatase level (AP) is a measure of the phosphatase activity throughout the skeleton, i.e. the activity of normal bone tissue as well as that of Pagetic bone, in proportion to their respective volumes. This test therefore greatly under-estimates the activity of Pagetic bone in localized forms of the disease. To accurately evaluate the activity of Pagetic bone, the value of AP needs to be expressed in terms of the percentage of bone tissue affected by the disease. Two tables enable us to assess this percentage approximately. It is therefore possible to evaluate the activity of Pagetic bone on the basis of the tables presented by the authors. We can see that localized forms of Paget's disease may have an alkaline phosphatase activity of 2 000 or 3 000 I.U., while the AP levels in the blood are less than 200. So, in the presence of localized forms of the disease, we are unable to say that the disease is barely active on the basis of very low values for AP. It is important to treat localizations which have a "functional" risk for the future, especially when there localizations are highly active. The histopathological and scintigraphic data are compatible with areas of ery high activity. A similar rationale should be applied to the figures obtained for urinary hydroxyproline and the results of 45Ca kinetic studies.

[The joint in algodystrophy. Joint fluid, synovium, cartilage]. / L'articulation dans l'algodystrophie. Le liquide articulaire, la synoviale, le cartilage.

The joint fluid in cases of algodystrophy was studied in 17 samples. It is poor in cells (275/mm3 with a mean of 15% polymorphs). The protein level was studied 4 times and was equal to or greater than 40 g/l, i.e. double the normal value. A detailed histological examination of 33 biopsies of synovial tissue reveals a typical appearance of the synovium in algodystrophy, defined by 6 features, 2 negative and 4 positive: absence of hyperplasia of the synovial lining, absence of any real inflammatory cell infiltrate, presence of a marked hypervascularity, an oedema of the chorion, especially marked in the first weeks of the disease, hyperplasia of the walls of some arterioles, and fibrosis of the chorion which becomes more marked as the disease progresses and which is predominantly in the deeper layers. The authors recall that articular cartilage can show superficial alterations of structure with areas of fibrosis.

[Bone and phosphoro-calcium metabolism in reflex sympathetic dystrophy]. / L'os et le métabolisme phosphocalcique dans l'algodystrophie.

A combined study organised by the French Society of Rheumatology was devoted to the investigation of bone and phosphoro-calcium metabolism in cases of reflex sympathetic dystrophy. The following observations were made: the usual phosphoro-calcium parameters are not altered, apart from a slight elevation of the urinary calcium in multifocal forms of the disease, during the 3rd and 4th months; the level of PTH, studied in 11 patients, was normal in each case; the examination of 8 bone biopsies, one performed in the 7th week and six others performed during the 3rd and 4th months of the disease, showed, initially, invasion of the spongy tissue by oedema, signs of marrow stress and bone stress, with a reduction in the number of osteoblasts, without any marked alteration of bone remodelling. At a later stage, the biopsy shows intense bone remodelling with hyperosteoclastosis and hyperosteoblastosis and the formation of irregular bone tissue which later becomes lamellar. Electron microscopic study of two biopsies revealed signs of acellular demineralisation with normal appearance of the osteoblasts and osteoclasts.