Avascular necrosis of the femoral head in children with chronic renal disease

Histopathological and immunohistochemical aspects of bone tissue in aseptic necrosis of the femoral head

Femoral head osteonecrosis, also known as avascular necrosis, is a disease with a multifactorial etiology, characterized by a profound change of bone architecture, which leads to the diminishing of bone resistance and femoral head collapse. The main causes that lead to femoral head necrosis are represented by the decrease of local blood perfusion and increase of intraosseous pressure, because of an excessive development of adipose tissue in the areolas of the trabecular bone tissue in the femoral head. The histopathological and immunohistochemical (IHC) study performed by us showed that most of bone trabeculae were damaged by necrotic-involutive processes, their sizes being reduced, both regarding their length and their diameter; generally, the spans were thin, fragmented, distanced among them, which led to the occurrence of some large areolar cavities, full of conjunctive tissue, rich in adipocytes. Some of the residual bone spans even presented microfractures. In the structure of the trabecular bone tissue, numerous cavities showed lack of content, which indicates the death of osteocytes inside, while the endosteum appeared very thin, with few osteoprogenitor, flattened, difficult to highlight cells. The IHC study showed a low reaction of the bone reparatory processes and a reduced multiplication capacity of bone cells involved in the remodeling and remake of the diseased bone tissue. Nevertheless, there were identified numerous young conjunctive cells (fibroblasts, myofibroblasts), positive to proliferating cell nuclear antigen (PCNA), cells that have a high capacity of multiplication, participating in the formation of a fibrous conjunctive tissue (sclerous) instead of the damaged bone trabeculae. The formation of fibrous conjunctive tissue causes the reduction of mechanical resistance of the femoral head and its collapse. The IHC study of the microvascularization in the femoral head damaged by aseptic osteonecrosis showed the presence of a very low vascular system, both in the residual bone trabeculae and in the sclerous conjunctive tissue. Of the inflammatory cells present in the spongy bone tissue of the femoral head affected by osteonecrosis, the most numerous ones were the macrophages. Both macrophages and T- and B-lymphocytes had a heterogenous distribution.

Bone Marrow Multipotent Mesenchymal Stromal Cells as Autologous Therapy for Osteonecrosis: Effects of Age and Underlying Causes

Bone marrow (BM) is a reliable source of multipotent mesenchymal stromal cells (MSCs), which have been successfully used for treating osteonecrosis. Considering the functional advantages of BM-MSCs as bone and cartilage reparatory cells and supporting angiogenesis, several donor-related factors are also essential to consider when autologous BM-MSCs are used for such regenerative therapies. Aging is one of several factors contributing to the donor-related variability and found to be associated with a reduction of BM-MSC numbers. However, even within the same age group, other factors affecting MSC quantity and function remain incompletely understood. For patients with osteonecrosis, several underlying factors have been linked to the decrease of the proliferation of BM-MSCs as well as the impairment of their differentiation, migration, angiogenesis-support and immunoregulatory functions. This review discusses the quality and quantity of BM-MSCs in relation to the etiological conditions of osteonecrosis such as sickle cell disease, Gaucher disease, alcohol, corticosteroids, Systemic Lupus Erythematosus, diabetes, chronic renal disease and chemotherapy. A clear understanding of the regenerative potential of BM-MSCs is essential to optimize the cellular therapy of osteonecrosis and other bone damage conditions.

Avascular Necrosis of Femoral Head: A Metabolomic, Biophysical, Biochemical, Electron Microscopic and Histopathological Characterization

Avascular necrosis of the femur head (AVNFH) is a debilitating disease caused due to the use of alcohol, steroids, following trauma or unclear (idiopathic) etiology, affecting mostly the middle aged population. Clinically AVNFH is associated with impaired blood supply to the femoral head resulting in bone necrosis and collapse. Although Homocysteine (HC) has been implicated in AVNFH, levels of homocysteine and its associated pathway metabolites have not been characterized. We demonstrate elevated levels of homocysteine and concomitantly reduced levels of vitamins B6 and B12, in plasma of AVNFH patients. AVNFH patients also had elevated blood levels of sodium and creatinine, and reduced levels of random glucose and haemoglobin. Biophysical and ultrastructural analysis of AVNFH bone revealed increased remodelling and reduced bone mineral density portrayed by increased carbonate to phosphate ratio and decreased Phosphate to amide ratio together with disrupted trabeculae, loss of osteocytes, presence of calcified marrow, and elevated expression of osteocalcin in the osteoblasts localized in necrotic regions. Taken together, our studies for the first time characterize the metabolomic, pathophysiological and morphometric changes associated with AVNFH providing insights for development of new markers and therapeutic strategies for this debilitating disorder.

Various musculoskeletal manifestations of chronic renal insufficiency

Musculoskeletal manifestations in chronic renal insufficiency are caused by complex bone metabolism alterations, now described under the umbrella term of chronic kidney disease mineral- and bone-related disorder (CKD-MBD), as well as iatrogenic processes related to renal replacement treatment. Radiological imaging remains the mainstay of disease assessment. This review aims to illustrate the radiological features of CKD-MBD, such as secondary hyperparathyroidism, osteomalacia, adynamic bone disease, soft-tissue calcifications; as well as features associated with renal replacement therapy, such as aluminium toxicity, secondary amyloidosis, destructive spondyloarthropathy, haemodialysis-related erosive arthropathy, tendon rupture, osteonecrosis, and infection.

Comparison of clinical outcomes by different renal replacement therapy in patients with end-stage renal disease secondary to lupus nephritis

BACKGROUND/AIMS

Many studies have compared patients with systemic lupus erythematosus (SLE) on renal replacement therapy (RRT) with non-lupus patients. However, few data are available on the long-term outcome of patients with end-stage renal disease (ESRD) secondary to SLE who are managed by different types of RRTs.

METHODS

We conducted a retrospective multicenter study on 59 patients with ESRD who underwent maintenance RRT between 1990 and 2007 for SLE. Of these patients, 28 underwent hemodialysis (HD), 14 underwent peritoneal dialysis (PD), and 17 patients received kidney transplantation (KT). We analyzed the clinical outcomes in these patients to determine the best treatment modality.

RESULTS

The mean follow-up period was 5 ± 3 years in the HD group, 5 ± 3 years in the PD group, and 10 ± 5 years in the KT group (p = 0.005). Disease flare-up was more common in the HD group than in the KT group (p = 0.012). Infection was more common in the PD and HD groups than in the KT group (HD vs. KT, p = 0.027; PD vs. KT, p = 0.033). Cardiovascular complications were more common in the HD group than in the other groups (p = 0.049). Orthopedic complications were more common in the PD group than in the other groups (p = 0.028). Bleeding was more common in the HD group than in the other groups (p = 0.026). Patient survival was greater in the KT group than in the HD group (p = 0.029). Technique survival was lower in the PD group than in the HD group (p = 0.019).

CONCLUSIONS

Among patients with ESRD secondary to SLE, KT had better patient survival and lower complication rates than HD and lower complication rates than PD. The prognosis between the HD and PD groups was similar. We conclude that if KT is not a viable treatment option, any alternative treatment should take into account the patient's general condition and preference.

Assessment and treatment of short stature in pediatric patients with chronic kidney disease: a consensus statement

Growth failure is a clinically important issue in children with chronic kidney disease (CKD) and is associated with significant morbidity and mortality. Many factors contribute to impaired growth in these children, including abnormalities in the growth hormone (GH)-insulin-like growth factor-I (IGF-I) axis, malnutrition, acidosis, and renal bone disease. The management of growth failure in children with CKD is complicated by the presence of other disease-related complications requiring medical intervention. Despite evidence of GH efficacy and safety in this population, some practitioners and families have been reluctant to institute GH therapy, citing an unwillingness to comply with daily injections, reimbursement difficulties, or impending renal transplantation. Suboptimal attention to growth failure management may be further compounded by a lack of clinical guidelines for the appropriate assessment and treatment of growth failure in these children. This review of growth failure in children with CKD concludes with an algorithm developed by members of the consensus committee, outlining their recommendations for appropriate steps to improve growth and overall health outcomes in children with CKD.

Growth hormone therapy before and after pediatric renal transplant

Children undergoing successful renal transplantation anticipate optimal growth and development. The use of rhGH pre- and post-Tx has been evaluated and supported by randomized control trials. Several strategies are required to maximize the potential benefit of this treatment in the renal population including provision of adequate nutrition intake, following bone parameters with appropriate interventions, and strategies to reduce steroid therapy including utilization of alternate day steroid treatment. Studies are required to further assess the impact of rhGH on renal allograft function, rejection risk, and allograft ultrastructural changes.

Avascular necrosis of common bones seen in the ED

Missed diagnosis of avascular necrosis (AVN) may result in substantial morbidity. Early diagnosis is crucial for appropriate intervention and, ultimately, improved outcome. Emerging physicians need to recognize AVN to avoid unsatisfactory clinical results for their patients. Avascular necrosis (AVN) of the bone can occur when the blood supply to the bone is disrupted and is usually found in areas with terminal circulation. Commonly involved bones include the femoral head, talus, and scaphoid.

Adverse events with rhGH treatment of patients with chronic renal insufficiency and end-stage renal disease

OBJECTIVE

Recombinant human growth hormone (rhGH) has been used to improve the growth retardation associated with chronic renal insufficiency (CRI) and end-stage renal disease. We determined the incidence of one of four targeted adverse events (AEs): malignancy, slipped capital femoral epiphysis (SCFE), avascular necrosis (AN), and intracranial hypertension (ICH).

STUDY DESIGN

During a 6.5-year period, we prospectively assessed patients enrolled in the CRI, dialysis, and transplant registries of the North American Renal Transplant Cooperative Study. The availability of an untreated control population facilitated determining whether or not there was the association between the AE and rhGH treatment.

RESULTS

Of the targeted AE, the only significant relation with rhGH treatment was the presence of ICH in patients with CRI; however, in all 3 instances, ICH occurred 2, 50, and 1131 days after discontinuation of rhGH. Considering that the mechanism of ICH in rhGH-treated patients is thought to be increased CSF production, rhGH probably had no role in the development of ICH in at least 2 of the 3 patients with CRI. A number of nontargeted AE were identified that have been associated with rhGH treatment in patients without renal disease. The incidence of glucose intolerance, pancreatitis, progressive deterioration of renal function, acute allograft rejection, and fluid retention were not more frequent in those receiving rhGH treatment compared with the control population.

CONCLUSIONS

This report validates the importance of a control population in ascribing AE to any therapeutic intervention. Previously identified AE associated with rhGH treatment are infrequent in patients with CRI and end-stage renal disease.