Osteonecrosis in renal transplant recipients. Early radiological detection and course

Steroid-induced osteonecrosis of bilateral distal humerus treated by arthroplasty using costal osteochondral graft: case report

We report the case of a 43-year-old man with steroid-induced osteonecrosis of the distal humerus in both arms. Costal osteochondral autografts were used to restore both joints with satisfactory outcomes.

Degree of corticosteroid treatment within the first 2 months of renal transplantation has a strong influence on the incidence of osteonecrosis of the femoral head

BACKGROUND AND PURPOSE

It has been suggested that avascular osteonecrosis (AVN) of the femoral head develops early after renal transplantation. We evaluated the relationship between risk of AVN and dose of steroids administered in different time periods.

METHODS

Development of AVN was determined using MRI at 3-6 weeks, 9-12 weeks, 24 weeks, and 12 months after transplantation in 150 patients (96 males). We investigated possible associations between acute rejection reactions, the dose of cyclosporine, tacrolimus use, total steroid dose by the second, fourth, sixth, or eighth weeks after transplantation, and incidence of AVN.

RESULTS

There was no statistically significant difference between incidence of AVN and presence or absence of an acute rejection reaction. We found a statistically significant association between AVN incidence and the total dose of steroids administered during the first 2 months after transplantation, and there was a doseresponse relationship. No other statistically significant associations were found.

INTERPRETATION

Our findings confirm that the total dose of steroids given within the first 2 months after renal transplantation has a great influence on the incidence of AVN.

Imaging of renal osteodystrophy

Chronic renal insufficiency, hemodialysis, peritoneal dialysis, renal transplantation and administration of different medications provoke complex biochemical disturbances of the calcium-phosphate metabolism with wide spectrum of bone and soft tissue abnormalities termed renal osteodystrophy. Clinically most important manifestation of renal bone disease includes secondary hyperparathyroidism, osteomalacia/rickets, osteoporosis, adynamic bone disease and soft tissue calcification. As a complication of long-term hemodialysis and renal transplantation amyloid deposition, destructive spondyloarthropathy, osteonecrosis, and musculoskeletal infections may occur. Due to more sophisticated diagnostic methods and more efficient treatment classical radiographic features of secondary hyperparathyroidism and osteomalacia/rickets are now less frequently seen. Radiological investigations play an important role in early diagnosis and follow-up of the renal bone disease. Although numerous new imaging modalities have been introduced in clinical practice (scintigraphy, CT, MRI, quantitative imaging), plain film radiography, especially fine quality hand radiograph, still represents most widely used examination.

Dialysis bone disease

The bone disease associated with end-stage renal failure (ESRD) and treatment are complex and multifactorial, and has changed in both clinical and imaging features over the past three decades. Whereas previously features of vitamin D deficiency (rickets/osteomalacia) and intense, and prolonged, secondary hyperparathyroidism (bone resorption, osteosclerosis, metastatic calcification) predominated, these features are now rarely evident radiologically. This has occurred through the better understanding of vitamin D metabolism and improvements in therapeutic management. However, metastatic calcification in soft tissues and 'adynamic" bone continue to be problematic. New complications have developed as a consequence of treatment (dialysis and transplantation), including amyloid deposition, noninfective sponyloarthropathy, osteonecrosis, and osteopenia/osteoporosis). Radiographs remain the most widely used imaging technique in examining for skeletal disease in patients with ESRD on maintenance dialysis. Occasionally, more sophisticated imaging (CT, MRI, nuclear medicine scanning) are helpful (parathyroid tumor localization, differentiation between infection and amyloid deposition). Developments in quantitative methods to assess bone density enable the effects of ESRD and treatment to be studied and monitored. Technical developments in computed tomography (rapid, multislice scanning) allow quantitation and monitoring of metastatic cardiac calcification in patients on hemodialysis, which has relevance to prognosis.

Initial changes of non-traumatic osteonecrosis of femoral head in fat suppression images: bone marrow edema was not found before the appearance of band patterns

The present study examined initial changes in non-traumatic osteonecrosis of the femoral head (ONF) on T1- and T2-weighted MR images, and fat suppression images. The subjects were 57 renal transplant recipients (37 males and 20 females), whose median age at the time of transplantation was 31.5 years old (range, 10 to 58 years). Twelve patients developed band patterns (sign of established ONF) at an early postoperative period. Among them, 4 joints of 3 patients had a localized, faint signal abnormality in fat suppression images, where band pattern was confirmed later in T1- and T2-weighted images. In all the 57 patients, no bone marrow edema preceding to ONF was observed. Bone marrow edema would not be the cause of ONF in renal transplant patients. Early changes depicted in our fat suppression images would be useful information in the studies on pathogenesis of ONF.

The Nicolas Andry award. The pathogenesis and prevention of steroid-induced osteonecrosis

The effects of steroids on a cloned pluripotential cell from bone marrow stroma were examined in vitro in culture and in vivo after the cells were transfected with a traceable gene and transplanted into host mice. Bipedal chickens were treated with steroids to establish a model for osteonecrosis. The effects of a lipid lowering agent, lovastatin, on the prevention of steroid induced adipogenesis in vitro in cell culture, and on adipogenesis and osteonecrosis in vivo in chickens, were evaluated. On treatment with dexamethasone, cloned pluripotential cells began to differentiate into adipocytes and expressed a fat specific gene, whereas the expression of Type I collagen and osteocalcin messenger ribonucleic acid decreased. Addition of lovastatin in culture inhibited steroid induced fat gene expression and counteracted the inhibitory effect of steroids on osteoblastic gene expression. Cloned pluripotential cells were transduced with a traceable retrovirus vector encoding the beta-galactosidase and neomycin resistance genes. The transfected cells were administered to mice either by tail vein or by direct intramedullary injection. Half of the animals in each group were treated with steroids. Histologic sections showed the appearance of transplanted cells in the marrow. Analysis of marrow blowouts by flow cytometry revealed that steroid treatment produced adipogenesis in transplanted cells. Evidence of osteonecrosis was observed in steroid treated chickens, whereas sections from animals treated with steroids and lovastatin showed less adipogenesis and no bone death. The results indicate that steroid induced adipogenesis in the marrow may contribute to osteonecrosis and that lovastatin may be helpful in preventing the development of steroid induced osteonecrosis.

Renal bone disease: radiological investigation

The bone disease associated with chronic renal impairment is complex and multifactorial, and has changed over past decades. Whereas originally features of vitamin D deficiency (rickets/osteomalacia) and secondary hyperparathroidism (erosions, osteosclerosis, brown cysts) predominated, improvement in management and therapy have resulted in such readiographic features being present in a minority of patients. Metastatic calcification and "adynamic" bone develop as a complication of disease (phosphate retention) and treatment (phosphate binders). New complications (amyloid deposition, noninfective spondyloarthropathy, osteonecrosis) are now seen complicating long-term hemodialysis and/or renal transplantation. Radiographs remain the most important imaging technique, but occasionally other imaging and quantitative techniques (CT, MRI, bone densitometry) are relevant to diagnosis and management.

Steroid-induced adipogenesis in a pluripotential cell line from bone marrow

We studied the effect of steroids on the differentiation of a pluripotential mesenchymal cell with use of a cell line (D1) from mouse bone-marrow stroma. The cells were treated with increasing (10[-9], 10(-8), and 10(-7)-molar) concentrations of dexamethasone for increasing durations ranging from forty-eight hours to twenty-one days. The appearance of triglyceride vesicles in the cells indicated that this treatment had induced the differentiation of the cell into adipocytes. The number of cells that contained the triglyceride vesicles and the expression of a fat-cell-specific gene, 422(aP2), increased with longer durations of exposure to dexamethasone and with higher concentrations of the steroid. Treatment with dexamethasone also diminished the expression of alpha1 type-I collagen mRNA and osteocalcin mRNA. The data indicate that dexamethasone stimulates the differentiation of cells in bone-marrow stroma into adipocytes as well as the accumulation of fat in the marrow at the expense of expression of type-I collagen and osteocalcin mRNA, thereby suppressing differentiation into osteoblasts.

CLINICAL RELEVANCE

Steroid-induced adipogenesis by bone progenitor cells in marrow may influence the development of osteonecrosis. It is therefore important to consider the investigation of a treatment, such as the inhibition of the metabolism and accumulation of fat in marrow, that can prevent the onset of osteonecrosis.

Avascular necrosis of bone after cardiac transplantation. Prevalence and relationship to administration and dosage of steroids

We studied the relationship of the administration and dosage of steroids to the development of avascular necrosis of bone in 168 patients who had had a heart transplantation (156 patients) or a heart and lung transplantation (twelve patients). One hundred and forty-one of the patients were male and twenty-seven were female. The average age was forty-five years (range, seven to sixty-six years). The average duration of follow-up was forty months (range, twelve to eighty months). Avascular necrosis developed in five patients (3 per cent). The femoral head was involved in three patients (bilaterally in two and unilaterally in one), the medial femoral condyle was involved bilaterally in one, and several sites were involved in the fifth patient. The avascular necrosis was diagnosed an average of five months (range, two to eleven months) after the transplantation. In order to evaluate the influence of the dosage of the steroids on the development of avascular necrosis of bone, the doses of prednisone and Solu-Medrol (methylprednisolone) at one week, one month, six months, and one year after the transplantation were calculated for each patient. There was no association between the cumulative dose of prednisone and the development of avascular necrosis. There was, however, a strong statistical association (p = 0.005), as determined with pooled two-tailed variance analysis, between the cumulative dose of Solu-Medrol administered in the first month after the transplantation and the development of avascular necrosis.

Use of the uncemented bipolar endoprosthesis for the treatment of steroid-induced osteonecrosis of the hip in renal transplantation patients

Osteonecrosis of the hip is a well known complication in renal transplantation patients who are treated with corticosteroids for immunosuppression. In a consecutive series of 10 patients with osteonecrosis of the hip, 16 primary uncemented bipolar endoprostheses were inserted between April 1984, and February 1986. The average follow-up period after surgery was 40 months, (range, 24-48 months). All patients developed osteonecrosis of their hips and were operated on within 2 years of their renal transplant. At the time of surgery, all patients were still taking corticosteroids as well as other immunosuppressants. The average age at surgery was 34.6 years (range, 21-48 years). All hips were classified as stage 3 or 4 before operation. The average Harris score at follow-up examination was 94.2 (range, 74-101), with 13 hips rated excellent, 1 hip rated good, and 1 hip rated fair. One patient's hip prosthesis was removed after 17 months secondary to a septic arthritis. This was the only major complication in this series. Pain was improved in all patients. However, postoperative limp and abductor weakness still presented a significant problem. An extensive radiographic evaluation was made on all hips. Eleven observations and measurements were made using radiographs of the pelvis and hip. Vertical subsidence was present in 33% of the hips and averaged 2.2 mm (range, 1-4 mm). No significant radiographic loosening was evident in any hip. Acetabular protrusio was evaluated in all patients, and was found to be less than 4 mm in either the superior or axial direction. Heterotopic ossification was present in 80% of hips, but resulted in loss of motion in only one hip.(ABSTRACT TRUNCATED AT 250 WORDS)

Osteonecrosis and fractures following renal transplantation

Skeletal radiological surveys in 161 renal transplant recipients identified 36 patients with 115 lesions of osteonecrosis. A further two patients with osteonecrosis found at autopsy had had no radiographic abnormality. The total incidence of osteonecrosis was, therefore, 38 (24%) out of 161. The lesions were frequently multiple and bilateral with structural failure being the most common initial abnormality and the femoral head the most frequent site. Lesions also occurred in the femoral condyles, the talus, the humeral heads and the metatarsals, many being symptom-free. Calcification was demonstrated in the femoral and tibial shafts. The initial radiological abnormality appeared at a mean interval of 19 months after transplant but could occur as late as 75 months. Significantly fewer patients, three (7%) out of 41, developed osteonecrosis following a low-dose prednisolone regimen (0.8 g) compared with a high-dose group (2.8 g) where 35 (29%) out of 120 were affected. More females than males developed osteonecrosis, but no correlation could be demonstrated with regard to age, primary renal disease, number and type of transplant and duration of dialysis prior to transplant. Osteonecrosis is a complication which can be reduced with a low-dose prednisolone regimen. Most lesions will be demonstrated by radiological survey undertaken during the second and fourth years after transplantation.

Arthroscopy in steroid-induced osteonecrosis of the knee

Arthroscopic examination and treatment of 10 knees involved with steroid-induced osteonecrosis offered an effective method of thoroughly evaluating the extent of intraarticular disease and provided a means of debriding the joints with advanced lesions, giving consistent relief of internal derangement symptoms and, in some cases, improved functional status. If this provides prolonged relief, which it seems to be accomplishing in some of the longer follow-ups, then, quite likely, we will prevent or at least postpone the next level of treatment--joint replacement.