Hospitalized avascular necrosis after renal transplantation in the United States

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.

Risk factors for symptomatic Avascular Necrosis (AVN) in a multi-ethnic Systemic Lupus Erythematosus (SLE) cohort

Avascular necrosis of bone (AVN) is increasingly being recognized as a complication of SLE and causes significant disability due to pain and mobility limitations. We studied the prevalence and factors associated with avascular necrosis (AVN) in a multiethnic SLE cohort. SLE patients who visited the outpatient clinic from October 2017 to April 2019 were considered eligible. Their medical records were reviewed to identify patients who developed symptomatic AVN, as confirmed by either magnetic resonance imaging or plain radiography. Subsequently, their SLE disease characteristics and treatment were compared with the characteristics of patients who did not have AVN. Multivariable logistic regression analyses were performed to determine the independent factors associated with AVN among the multiethnic SLE cohort. A total of 390 patients were recruited, and the majority of them were females (92.6%); the patients were predominantly of Malay ethnicity (59.5%), followed by Chinese (35.9%) and Indian (4.6%). The prevalence of symptomatic AVN was 14.1%, and the mean age of AVN diagnosis was 37.6 ± 14.4 years. Both univariate and multivariable logistic regression analyses revealed that a longer disease duration, high LDL-C (low density lipoprotein cholesterol), positive anti-cardiolipin (aCL) IgG and anti-dsDNA results, a history of an oral prednisolone dose of more than 30 mg daily for at least 4 weeks and osteoporotic fractures were significantly associated with AVN. On the other hand, hydroxychloroquin (HCQ), mycophenolate mofetil (MMF) and bisphosphonate use were associated with a lower risk of AVN. No associations with ethnicity were found. In conclusion, several modifiable risk factors were found to be associated with AVN, and these factors may be used to identify patients who are at high risk of developing such complications. The potential protective effects of HCQ, MMF and bisphosphonates warrant additional studies.

Comparison of total joint arthroplasty outcomes between renal transplant patients and dialysis patients-a meta-analysis and systematic review

OBJECTIVES

End-stage renal disease (ESRD) patients are at an increased risk of needing total joint arthroplasty (TJA); however, both dialysis and renal transplantation might be potential predictors of adverse TJA outcomes. For dialysis patients, the high risk of blood-borne infection and impaired muscular skeletal function are threats to implants' survival, while for renal transplant patients, immunosuppression therapy is also a concern. There is still no high-level evidence in the published literature that has determined the best timing of TJA for ESRD patients.

METHODS

A literature search in MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials (up to November 2019) was performed to collect studies comparing TJA outcomes between renal transplant and dialysis patients. Two reviewers independently conducted literature screening and quality assessments with the Newcastle-Ottawa Scale (NOS). After the data were extracted, statistical analyses were performed.

RESULTS

Compared with the dialysis group, a lower risk of mortality (RR = 0.56, Cl = [0.42, 0.73], P < 0.01, I² = 49%) and revision (RR = 0.42, CI = [0.30, 0.59], P < 0.01, I² = 43%) was detected in the renal transplant group. Different results of periprosthetic joint infection were shown in subgroups with different sample sizes. There was no significant difference in periprosthetic joint infection in the small-sample-size subgroup, while in the large-sample-size subgroup, renal transplant patients had significantly less risk (RR = 0.19, CI = [0.13, 0.23], P < 0.01, I² = 0%). For dislocation, venous thromboembolic disease, and overall complications, there was no significant difference between the two groups.

CONCLUSION

Total joint arthroplasty has better safety and outcomes in renal transplant patients than in dialysis patients. Therefore, delaying total joint arthroplasty in dialysis patients until renal transplantation has been performed would be a desirable option. The controversy among different studies might be partially accounted for that quite a few studies have a relatively small sample size to detect the difference between renal transplant patients and dialysis patients.

Transitional changes in the incidence of hip osteonecrosis among renal transplant recipients

BACKGROUND

Immunosuppressive therapy for renal allograft recipients has changed substantially since the introduction of the anti-CD25 monoclonal antibody, basiliximab. We hypothesized that recent improvements in immunosuppressive treatment may reduce the incidence of osteonecrosis of the femoral head (ONFH). This study aimed to investigate transitional changes in the incidence of OFNH among renal transplant recipients by MRI.

METHODS

Participants comprised 110 patients who had undergone renal transplantation from 2003 to 2012, during which time basiliximab was in regular use at our institute (Recent group), and 232 patients who had undergone RT between 1986 and 2003 (Past group). We compared ONFH incidence between the two groups and evaluated risk factors for ONFH, including immunosuppressants (calcineurin inhibitors, basiliximab, and/or steroids) and postoperative renal function.

RESULTS

Incidence of ONFH was lower in the Recent group (0%) than in the Past group (3.4%; p = 0.043). In the Recent group, age was greater, ABO/human leukocyte antigen incompatibility was worse, while steroid dose was decreased and post-transplant renal function was improved. Cumulative methylprednisolone dose at postoperative week 2 and delayed graft function were identified as risk factors for ONFH.

CONCLUSION

Risk of ONFH after renal transplantation has fallen with the advent of regular use of basiliximab, although this agent does not appear to be a factor directly associated with the incidence of ONFH.

STUDY DESIGN

Clinical prognostic study (Level III case control study).

Complications and Readmission Incidence Following Total Hip Arthroplasty in Patients Who Have End-Stage Renal Failure

BACKGROUND

The number of patients who have end-stage renal disease undergoing primary total hip arthroplasty (THA) has increased over the past decade. The purpose of this study is to evaluate mortality, complications, and 90-day readmission incidences in patients who have end-stage renal disease undergoing THA.

METHODS

Patients who had a primary THA between January 1, 2007, and December 31, 2016, were identified from the 5% Medicare database. A total of 55,297 THA patients were stratified into 3 groups: renal dialysis (without transplant), renal transplant, and those without such renal problems. Risk of readmissions, dislocations, periprosthetic joint infections (PJIs), venous thromboembolic diseases, and mortalities up to 5 years following primary THA was compared. Multivariate Cox regression analyses were used to evaluate the effect of patient and hospital characteristics on the adjusted complication risks.

RESULTS

Mortalities at 5 years was 62.6% in the renal dialysis group, 37.3% in the renal transplant group, compared to 15.0% in the nonrenal group. Dislocations (7.6%) and PJIs (7%) were significantly higher in the dialysis group (P < .001). No significant differences in venous thromboembolic diseases (all timepoints) and revisions (all timepoints except at 90 days) between the renal groups were observed. The 90-day readmission risks were significantly greater in both the dialysis (55%) and transplant (43%) groups compared to the nonrenal cohort (30%) (P < .001).

CONCLUSION

Renal dialysis patients undergoing THA are at increased risk of PJIs (7%), dislocations (7.6%), revisions, and mortalities at 90 days compared to transplant and nonrenal patients. Both dialysis and transplant patients are high-risk groups with significantly increased 90-day readmission incidences of 55% and 43%, respectively, which makes their inclusion into a bundled payment model challenging.

Opioid Prescription, Morbidity, and Mortality in US Transplant Recipients

BACKGROUND

Centers for Disease Control and Prevention guidelines recommend caution in prescribing opioids for chronic pain. The characteristics of opioid prescription (OpRx) among kidney transplant (KTx) recipients have not been described in a national population.

METHODS

We assessed OpRx prevalence among prevalent KTx recipients, and associated duration (long-term, defined as ≥90 days in a year) and dosing (in morphine milligram equivalents per day of <50, 50-89, and ≥90) with outcomes, death and graft loss, among incident KTx recipients using 2006-2010 US Renal Data System files, including Medicare Part D for medication ascertainment. Cox models controlled for recipient factors.

RESULTS

Of 36,486 KTx recipients in the 2010 prevalent cohort, approximately 14.6% had long-term OpRx. The strongest association with long-term OpRx after KTx was long-term OpRx before KTx (64%; adjusted odds ratio, 95% confidence interval, 95.2, 74.2-122.1). Incident KTx recipients with long-term OpRx had increased risk of mortality and graft loss compared with those without OpRx or short-term OpRx after KTx. This risk was highest among recipients with long-term OpRx doses of ≥90 morphine milligram equivalents or higher per day (adjusted hazard ratio, 95% confidence interval, 1.61, 1.24-2.10 for death, and 1.33, 1.05-1.67 for graft loss, respectively).

CONCLUSIONS

In contrast to either no or short-term OpRx, long-term, and especially long-term high-dose OpRx, is associated with increased risk of death and graft loss in US KTx recipients. Causal relationships cannot be inferred, and OpRx may be an illness marker. Nevertheless, efforts to treat pain effectively in KTx recipients with less toxic interventions and decrease OpRx deserve consideration.

Complications and Mortality in Chronic Renal Failure Patients Undergoing Total Joint Arthroplasty: A Comparison Between Dialysis and Renal Transplant Patients

BACKGROUND

In total joint arthroplasty (TJA) literature, there is a paucity of large cohort studies comparing chronic kidney disease (CKD) and end-stage renal disease (ESRD) vs non-CKD/ESRD patients. Thus, the purposes of this study were (1) to identify inhospital complications and mortality in CKD/ESRD and non-CKD/ESRD patients and (2) compare inhospital complications and mortality between dialysis and renal transplantation patients undergoing TJA.

METHODS

We queried the Nationwide Inpatient Sample database for patients with and without diagnosis of CKD/ESRD and those with a renal transplant or on dialysis undergoing primary or revision total knee or hip arthroplasty from 2007 to 2011. Patient comorbidities were identified using the Elixhauser comorbidity index. International Classification of Diseases, Ninth Revision, codes were used to identify postoperative surgical site infections (SSIs), wound complications, deep vein thrombosis, and transfusions.

RESULTS

Chronic kidney disease/ESRD was associated with greater risk of SSIs (odds ratio [OR], 1.4; P<.001), wound complications (OR, 1.1; P=.01), transfusions (OR, 1.6; P<.001), deep vein thrombosis (OR, 1.4; P=.03), and mortality (OR, 2.1; P<.001) than non-CKD/ESRD patients. Dialysis patients had higher rates of SSI, wound complications, transfusions, and mortality compared to renal transplant patients.

CONCLUSION

Chronic kidney disease/ESRD patients had a greater risk of SSIs and wound complications compared to those without renal disease, and the risk of these complications was even greater in CKD/ESRD patients receiving dialysis. These findings emphasize the importance of counseling CKD patients about higher potential complications after TJA, and dialysis patients may be encouraged to undergo renal transplantation before TJA.

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.

Metabolic bone diseases in kidney transplant recipients

Metabolic bone disease after kidney transplantation has a complex pathophysiology and heterogeneous histology. Pre-existing renal osteodystrophy may not resolve completely, but continue or evolve into a different osteodystrophy. Rapid bone loss immediately after transplant can persist, at a lower rate, for years to come. These greatly increase the risk of bone fracture and vertebral collapse. Each patient may have multiple risk factors of bone loss, such as steroids usage, hypogonadism, persistent hyperparathyroidism (HPT), poor allograft function, metabolic acidosis, hypophosphatemia, vitamin D deficiency, aging, immobility and chronic disease. Clinical management requires a comprehensive approach to address the underlying and ongoing disease processes. Successful prevention of bone loss has been shown with vitamin D, bisphosphonates, calcitonin as well as treatment of hypogonadism and HPT. Novel approach to restore the normal bone remodeling and improve the bone quality may be needed in order to effectively decrease bone fracture rate in kidney transplant recipients.

Rehospitalization after kidney transplantation during the first year: length, causes and relationship with long-term patient and graft survival

INTRODUCTION

There is a wide interest in epidemiologic studies assessing different causes of post-kidney transplantation rehospitalization. However, there is a paucity of knowledge on the long-term survival and graft function of rehospitalized kidney transplant recipients during the first year. Knowledge of posttransplant rehospitalization causes may help guide the preventive program at the first year. In our study, we assess causes for hospitalization and investigate the long-term patient and graft survival after non-fatal rehospitalization in kidney recipients during the first year.

MATERIALS AND METHODS

We retrospectively studied the medical histories of 419 kidney transplant recipients whose operations were performed between 1986 and 2009 at Charles Nicolle Hospital, in Tunis, Tunisia. Among these patients, a total of 296 posttransplant rehospitalizations of kidney transplant recipients during the first year occurring in 191 (45.5%) patients were assessed. Clinical characteristics of the patients, including gender, age, reason for kidney failure, weight, height, blood group, length of pretransplant dialysis, immunosuppressive regimen, postoperative complications, the length of hospital stay, transplantation-admission interval, causes of rehospitalizations, graft loss, and mortality rate were reviewed. For donors, these demographics included age, gender, blood group, type of donor (deceased or living), and relationship to the recipient. Because rehospitalizations are possible for more than one cause, the sum of frequencies of rehospitalization causes is more than 100%.

RESULTS

There was 1 rehospitalization in 121 patients, 2 rehospitalizations in 47 patients, 3 rehospitalizations in 15 patients, 4 rehospitalizations in 5 patients, 5 rehospitalizations in 2 patients and 6 rehospitalizations in 1 patient. Rehospitalization was more frequent for diabetic patients without significant association. The causes of rehospitalization were infection in 221 cases (55.5%), renal dysfunction in 106 cases (26%), cardiovascular event in 10 cases (2.4%), and diabetic ketoacidosis in 11 cases (2.7%). The length of hospital stay was 22.5 ± 29.6 days, 20.15 ± 22.16 days, 25 ± 30 days and 23.4 ± 27.5 days, respectively, in the first, second, third, and fifth rehospitalizations. Median hospital stay for all rehospitalizations was between 14 and 16 days. The risk factors of rehospitalization were: use of mycophenolate mofetile (P = .0072), use of cyclosporine (P = .0073), and cytomegalovirus infection (P < .001). There was no significant correlation between rehospitalization and either lost of graft and death.

CONCLUSIONS

During the first year after kidney transplantation, rehospitalization was especially required because of infections and renal dysfunction. The risk factors of rehospitalization were cadaveric graft, use of mycophenolate mofetil, use of cyclosporine, and cytomegalovirus infection. To prevent and minimize rehospitalizations during the first year, a specific preventive program based on infection prevention and graft function monitoring should be established.

Avascular osteonecrosis and accompanying anemia, leucocytosis, and decreased bone mineral density in renal transplant recipients

BACKGROUND

Avascular osteonecrosis (AVN) is a complication of renal transplantation. In this study, we present 12 cases of AVN associated with renal transplantation.

METHODS

Renal transplant recipients (RTRs) with AVN (group I [GI]) were evaluated by using magnetic resonance imaging and blood urea nitrogen, creatinine, glucose, calcium, phosphorus, magnesium, alkaline phosphatase, parathyroid hormone, and urine analysis. We evaluated bone mineral density (BMD) of the femoral neck and lumbar vertebrae. All patients were treated with steroids, cyclosporine, or tacrolimus plus mycophenolate mofetil. Twenty-six RTRs (GII) without AVN were randomly selected as control subjects.

RESULTS

The mean ages of GI and GII, were 33.81 ± 6.72 and 34.00 ± 7.65 years respectively (P > .05). The mean interval between transplantation and development of AVN was 12.08 ± 6.48 months. Although levels of blood urea nitrogen, creatinine, calcium, magnesium, and parathyroidhormone, as well as glucocorticoid doses in the first 12 months were similar in GI and GII, there were significant differences in serum alkaline phosphatase, hemoglobin levels, and white blood cell count between GI and GII (P < .05 for each). BMD T score <-1.5 was observed in 8/9 GI and 15/26 patients in GII. All of the patients with AVN except 1, were followed with conservative measures including calcium, magnesium, and vitamin D replacement therapies, bisphosphonate, and reduced or ceased glucocorticoid treatment. Although T scores of the femoral head were similar in GI and GII, the lumbar vertebral T score was significantly lower in GI than in GII (P < .052).

CONCLUSION

AVN developed within the first year after transplantation. Decreased lumbar vertebral BMD, which can be an indicator of glucocorticoid effect, accompanied AVN in nearly all patients. Despite the absence of renal dysfunction, increased bone destruction, anemia, and leucocytosis were coincidental or accompanying findings in our patients with AVN.

Is liver cirrhosis a risk factor for osteonecrosis of the femoral head in adults? A population-based 3-year follow-up study

BACKGROUND

The relationship between osteonecrosis of the femoral head (OFH) and liver cirrhosis is controversial. The aim of this study was to determine whether liver cirrhosis is associated with the occurrence of OFH.

METHODS

We used the National Health Insurance Database, derived from the Taiwan National Health Insurance program. The study cohort comprised 40,769 adult patients with liver cirrhosis. The comparison cohort consisted of 40,769 randomly selected age- and sex-matched subjects.

RESULTS

During the 3-year follow-up period, there were 321 (0.8%) cirrhotic patients with OFH, and 126 (0.3%) non-cirrhotic patients with OFH (p<0.001). Cox's regression analysis, adjusted by the patients' age, sex, and other confounding factors, showed that the cirrhotic patients had a higher risk for occurrence of OFH than non-cirrhotic patients during the 3-year period (hazard ratio=2.38, p<0.001). In this 3-year study, the incidence density of cirrhotic patients hospitalized for OFH was 3 episodes/1,000 person-year.

CONCLUSION

We conclude that cirrhotic patients have a higher risk for occurrence of OFH than non-cirrhotic patients.

Aftercare for patients with transplanted organs

BACKGROUND

The postoperative management following solid organ transplantation requires close cooperation between family doctors, internists, the local hospital, and the transplant center.

METHODS

Selective analysis of current national and international guidelines and relevant review articles.

RESULTS/CONCLUSION

In the early phase post transplantation, aftercare involves inpatient treatment and outpatient or inpatient rehabilitation with the aim of complete social and professional reintegration. Early diagnosis and treatment of typical general complications such as post-transplant diabetes, hyperlipidemia, arterial hypertension, osteoporosis, and kidney failure is essential. Early detection and treatment of malignant disease and opportunistic infections in patients with long-term immunosuppression is desirable. Moreover, organ-specific factors have to be taken into account. In the event of transplant dysfunction, recurrence of the underlying disease in the transplant, chronic or acute rejection, and organ-specific infections and drug toxicity have to be considered.

Management of metabolic bone disease in kidney transplant recipients

Bone disease after kidney transplantation has a complex pathophysiology and heterogeneous histology. Pre-existing renal osteodystrophy may not resolve completely, but continue or evolve into a different osteodystrophy. Rapid bone loss immediately after transplant can persist, at a lower rate, for years to come. These greatly increase the risk of bone fracture and vertebral collapse. Hypovitaminosis D, hyperparathyroidism and hyperaluminemia may resolve after kidney transplant, but many patients have other risk factors of bone loss, such as steroids usage, hypogonadism, persistent hyperparathyroidism, poor allograft function, aging, and chronic diseases. Clinical management requires a comprehensive approach to address the underlying and ongoing disease processes. Successful prevention of bone loss has been shown with vitamin D analogues, bisphosphonates and calcitonin. Novel approaches to restore the normal bone remodeling and improve the bone quality may be needed in order to effectively decrease bone fractures in kidney transplant recipients.

Total hip replacement in renal transplant patients

Avascular necrosis of the femoral head creates considerable morbidity in successful renal transplant recipients who are generally young and expect active lifestyles. Total hip replacement is considered the treatment of choice in these patients, but surgeons may be wary because of a supposed increase in the risk of infection and other complications. A review of the literature reveals that cemented hip arthroplasty provides good to excellent functional outcomes for renal transplant patients. Most authors have found that the risk of infection is not increased despite chronic immunosuppression, but the rates of general complications are and should be anticipated and treated. There is a high rate of early failure in these patients because of their young age and diffuse osteopenia as a result of secondary hyperparathyroidism related to the underlying renal disease and chronic steroid use. Recent studies have found that despite decreased bone stock in these patients, porous-coated prostheses are not contraindicated.

Avascular osteonecrosis after renal transplantation

Avascular osteonecrosis (AVN) is a serious osseous complication after renal transplantation. Its prevalence clearly decreased from 20% to 4% after introduction of cyclosporine and reduction of steroid doses. The aim of our study was to evaluate the frequency of AVN among kidney transplant recipients and to determine the risk factors by comparing them with a population without AVN. Among 326 kidney transplant recipients between June 1986 and December 2004, 15 patients developed AVN with mean age of 40.86 years, including 11 men and 4 women. Fifteen kidney transplant recipients without AVN were selected to be matched for age, gender, and date of transplantation (control group). Cases of symptomatic AVN were diagnosed by hip X-ray, radioisotope bone scan, or magnetic resonance imaging. AVN was diagnosed at a mean of 3.5 years after transplantation (range, 0.5-13 years). The main localization of AVN was the femoral head in 12 cases and the femoral condyle in 3 cases. We studied the following risk factors: the type of donor (cadaver or living donor), the duration on dialysis before transplantation, the cumulative steroid dose, the acute rejection rate, and the posttransplantation weight gain. Statistical analysis showed that the cumulative steroid dose and the acute rejection rate were higher among the AVN group than the control group (P=.04 and P=.058, respectively). The prevalence of AVN in our population is 4.6%, which is probably an underestimate since these were symptomatic cases. The reduction or early withdrawal of steroids remains the only efficient preventive treatment for AVN.

From marrow oedema to osteonecrosis: common paths in the development of post-transplant bone pain

Osteonecrosis, the calcineurin-inhibitor-induced pain syndrome and transient marrow oedema may occur after renal transplantation, are generally painful and can be diagnosed by X-ray, radionuclide scan or magnetic resonance imaging. They share features of increased intraosseous pressure, compromised vascular supply, marrow oedema and the development of a 'bone compartment syndrome'. Glucocorticoid dosage is the most commonly implicated risk factor for osteonecrosis. Mechanisms may include the differentiation of mesenchymal stem cells to adipocytes causing increased intraosseous pressure and collapse of marrow sinusoids, as well as increased osteoblast and osteocyte apoptosis. Some of these effects may be ameliorated by lipid lowering drugs. Calcineurin-inhibitors, particularly cyclosporine, may increase the risk of osteonecrosis because of vasoconstrictive effects and sirolimus may influence the development of osteonecrosis by potentiating the effects of calcineurin inhibitors or by influencing the lipid profile. For osteonecrosis, early stages are generally managed conservatively or with core decompression sometimes accompanied by bone grafting and more recently the injection of bone morphogenic protein. The use of iloprost to improve blood flow and bisphosphonates and RANK-ligand inhibition to reduce osteoclastic resorption of remaining trabecular structures are as yet unproven strategies. Unfortunately, the rate of total hip arthroplasty remains high. For the calcineurin-inhibitor-induced pain syndrome and transient marrow oedema, calcium channel blockers, the reduction or withdrawal of calcineurin-inhibitors and core decompression have been used. Although a lack of randomized controlled trials makes management decisions difficult, early recognition of these bone pain syndromes affords the best opportunity for avoiding prolonged pain or joint replacement surgery.

Risk factors for hospitalization for bacterial or viral infection in renal transplant recipients--an analysis of USRDS data

We previously showed that children are more likely to develop viral infections post-kidney transplant while adults are more likely to develop bacterial infections. In this study we determined the overall risk factors for hospitalization with either a bacterial (HBI) or a viral infection (HVI). We analyzed data from 28 924 United States Renal Data System (USRDS) Medicare primary renal transplant recipients from January 1996 to July 2000, for adjusted hazard ratio (AHR) for HBI or HVI in the first 3 years posttransplant. For HVI, significantly higher AHR was seen with (a) recipient age <18 years (AHR 1.57, 95% CI = 1.02, 2.42), (b) donor CMV positive (AHR 1.72, 95% CI = 1.34, 2.19). For HBI, significantly higher AHR was seen with (i) delayed graft function (AHR 1.28, 95% CI = 1.076, 1.518), (ii) primary renal diagnosis chronic pyelonephritis (AHR 1.71, 95% CI = 1.18, 2.49); (iii) associated pretransplant diabetes (AHR 1.80, 95% CI = 1.53, 2.12); (iv) female gender AHR 1.63, 95% CI = 1.41, 1.88). Lower AHR for HVI was seen in CMV-positive recipients and for HBI with more recent year of transplant. Other covariates did not impact significantly in either HVI or HBI.

Effects of Urinary Tract Infection on Outcomes after Renal Transplantation in Children

Urinary tract infection (UTI) is the most common infection after kidney transplantation. A previous analysis showed that late (>6 mo after transplantation) UTI is associated with earlier graft loss in adults. It was hypothesized that children who are younger than 18 yr would be at higher risk to develop UTI and develop graft loss after both early and late UTI. The US Renal Data System database was analyzed from 1996 to 2000 for Medicare claims (composite of inpatient and outpatient) for UTI up to 36 mo after transplantation. SPSS software and Cox regression models were used to determine association of UTI and age after adjustment for covariates. Early UTI was defined as occurring <6 mo after transplantation, and late UTI was defined as occurring > or =6 mo after transplantation. The risk for graft loss after early UTI was elevated in all children (adjusted hazard ratio [AHR] 5.47; 95% confidence interval [CI] 1.93 to 15.4; P < 0.001) but not after late UTI (AHR 2.09; 95% CI 0.56 to 7.80; P = 0.27). Risk for posttransplantation death was not increased significantly after either early UTI (AHR 1.23; 95% CI 0.37 to 4.08) or late UTI (relative risk 2.22; 95% CI 0.90 to 5.44). Boys aged 2 to 5 (versus age 13 to <18 years) were at significantly higher risk for UTI. In girls, only those in the youngest age category (0 to 1) had higher risk for UTI. Children are at greater risk for graft loss after early but not necessarily late UTI. UTI was not an independent predictor of death in this population.

Avascular Bone Necrosis of the Hip Joint after Solid Organ Transplantation in Childhood: A Clinical and MRI Analysis

BACKGROUND

Aseptic osteonecrosis is a well-known complication after solid organ transplantation in adults. The occurrence of osteonecrosis in growing age has been studied after kidney transplantation, but no systematic evaluation of the joints has been reported after heart or liver transplantation in childhood.

METHODS

A total of 196 children--93% of patients surviving kidney, liver and heart transplantation in Finland--participated in a cross-sectional survey. All children underwent a detailed clinical examination and filled out a questionnaire on musculoskeletal symptoms. Radiographs were taken in case of joint pain or abnormal clinical findings. In addition, magnetic resonance imaging (MRI) from the hips was taken on a random basis from 34 adult patients transplanted as a child. The mean follow-up time of all patients after transplantation was 9.2 years (range, 2.4 to 20.5 years).

RESULTS

Twenty-eight (14%) patients reported prolonged joint or limb pain without previous trauma. Specific etiology for the limb pain was not found in 10 (5.1%) patients. Osteonecrosis seen in radiographs or MRI was noted in seven (3.6%) patients, of which three had received kidney, three liver, and one heart graft. Femoral head was affected in five patients, as well as talus bilaterally in one patient and lateral femoral condyle in one patient. All patients were older than 12 years at the time of diagnosis of the osteonecrosis. MRI of the hips of 34 randomly selected patients showed only one asymptomatic necrosis of the femoral head.

CONCLUSIONS

Symptomatic osteonecrosis of the hip is uncommon after solid organ transplantation in childhood using the current immunosuppressive medications.

A case of avascular necrosis of the femoral head as initial presentation of chronic myelogenous leukemia

Chronic myelogenous leukemia (CML) is a malignant clonal disorder of hemopoietic stem cells characterized by abnormal proliferation and accumulation of immature granulocyte. Leukostasis is one of the complications of CML and is characterized by partial or total occlusion of microcirculation by aggregation of leukemic cells and thrombi leading to respiratory, ophthalmic or neurologic symptoms. We experienced a rare case of avascular necrosis of the femoral head as the initial presentation of chronic myelogenous leukemia. A 24-year-old male patient was admitted to our hospital with pain in the right hip joint. The patient was diagnosed to be suffering from chronic myelogenous leukemia by packed marrow with granulocytic and megakaryocytic hyperplasia and the presence of Philadelphia chromosome. The right hip joint pain was attributed to avascular necrosis of the femoral head. And the avascular necrosis could be considered as the complication of chronic myelogenous leukemia due to microcirculatory obstruction of the femoral head. The avascular necrosis of the right femoral head was treated with bipolar hemiarthoplasty.

Maintenance immunosuppression use and the associated risk of avascular necrosis after kidney transplantation in the United States

BACKGROUND

Avascular necrosis (AVN) after renal transplantation has been largely attributed to the use of corticosteroids. However, other risk factors such as microvascular thrombosis and hyperlipidemia have been well described and may be of increased importance in the era of early steroid cessation and avoidance. We hypothesized that maintenance immunosuppressive medications known to be associated with these risk factors for AVN would also be associated with a higher risk of AVN.

METHODS

By using the U.S. Renal Data System database, we studied 27,772 primary patients on Medicare who received a solitary kidney transplant between January 1, 1996, and July 31, 2000. Cox proportional hazards regression models were used to calculate adjusted hazard ratios (AHRs) for patient- and transplant-related factors (including allograft rejection) with Medicare claims for AVN. The intensity and duration of corticosteroid use could not be assessed.

RESULTS

Among patients who were prescribed sirolimus at discharge, 3.5% of patients who received the combination of sirolimus-cyclosporine A (CsA) demonstrated AVN, compared with 1.4% of patients who received the combination of sirolimus-tacrolimus (P=0.06 by chi). In Cox regression, CsA use (vs. tacrolimus) (AHR 1.36, 95% confidence interval, 1.09-1.71) was independently associated with an increased risk of AVN. Sirolimus use showed a trend toward significance (AHR 1.59, 95% confidence interval, 0.99-2.56), with no significant interaction with CsA.

CONCLUSIONS

Compared with other maintenance immunosuppression, AVN was significantly more common after use of CsA prescribed at the time of discharge for renal transplantation. Whether this increased risk of AVN was directly attributable to hyperlipidemia, microvascular thrombosis, or differences in corticosteroid dosing could not be determined.

Mycobacterium tuberculosis infection incidence in hospitalized renal transplant patients in the United States, 1998-2000

The incidence, risk factors, and prognosis for Mycobacterium tuberculosis (MTB) infection have not been reported in a national population of renal transplant recipients. We performed a retrospective cohort study of 15,870 Medicare patients who received renal transplants from January 1, 1998 to July 31, 2000. Cox regression analysis derived adjusted hazard ratios (AHR) for factors associated with a diagnosis of MTB infection (by Medicare Institutional Claims) and the association of MTB infection with survival. There were 66 renal transplant recipients diagnosed with tuberculosis infection after transplant (2.5 cases per 1000 person years at risk, with some falling off of cases over time). The most common diagnosis was pulmonary TB (41 cases). In Cox regression analysis, only systemic lupus erythematosus (SLE) was independently associated with TB. Mortality after TB was diagnosed was 23% at 1 year, which was significantly higher than in renal transplant recipients without TB (AHR, 4.13, 95% CI, 2.21, 7.71, p < 0.001). Although uncommon, MTB infection is associated with a substantially increased risk of mortality after renal transplantation. High-risk groups, particularly those with SLE prior to transplant, might benefit from intensified screening.

Thrombotic microangiopathy after renal transplantation in the United States

BACKGROUND

Analysis of the incidence, time to event, and risk factors for thrombotic microangiopathy (TMA) after renal transplantation (RT), has not been reported in a national population.

METHODS

This is a historical cohort study of 15,870 RT recipients in the United States Renal Data System (USRDS) with Medicare as their primary payer between January 1, 1998, and July 31, 2000, followed until December 31, 2000. Patients with Medicare claims with a diagnosis of TMA (International Classification of Diseases, 9th Revision, codes 283.11x or 446.6x) after RT were assessed by Cox regression.

RESULTS

Among patients with end-stage renal disease owing to hemolytic uremic syndrome (HUS), 29.2% later had TMA versus 0.8% of patients with ESRD owing to other causes. The incidence of TMA in RT recipients was 5.6 episodes per 1,000 person-years (PY; 189/1,000 PY; for recurrent TMA versus 4.9/1,000 PY for de novo TMA). The risk of TMA was highest for the first 3 months after transplant. Risk factors for de novo TMA included younger recipient age, older donor age, female recipient, and initial use of sirolimus. Patient survival rate after TMA was approximately 50% at 3 years.

CONCLUSION

De novo TMA is uncommon and may occur later after RT than previously reported. Risk factors for de novo TMA were also identified.