[Bisphosphonate-induced collapsing focal segmental glomerulosclerosis; two clinical cases and literature review]

Collapsing focal segmental glomerulosclerosis is well described in its idiopathic form, mostly seen in young African American patients, and in association with HIV virus. Its clinical presentation typically includes proteinuria and renal failure rapidly progressing to end stage renal disease. However, a new form has recently been described related to treatment with high doses of intravenous bisphosphonates, especially pamidronate. We report two cases of collapsing focal segmental glomerulosclerosis in patients treated with intravenous pamidronate. In opposition to previous reports, interruption of pamidronate administration did not improve renal function. The latter should be evaluated before initiating treatment with bisphosphonates and regularly monitored. For patients with chronic kidney disease, introduction of bisphosphonates should be reconsidered given the risk of rapid progression to end stage renal disease and the lack of evidence for reduction of fracture risk in this population.

Humoral and cellular rejection after combined liver-kidney transplantation in low immunologic risk recipients

Combined liver-kidney transplantation is considered a low risk for immunologic complication. We report an unusual case of identical ABO liver-kidney recipient without preformed anti-human leukocyte antigen (HLA) antibodies, transplanted across a T- and B-cell-negative cross-match and complicated by early acute humoral and cellular rejection, first in the liver then in the kidney. While analyzing the immunologic complications in our cohort of 12 low-risk combined liver-kidney recipients, only one recipient experienced a rejection episode without detection of anti-HLA antibody over time. Although humoral or cellular rejection is rare after combined kidney-liver transplantation, our data suggest that even in low-risk recipients, the liver does not always systematically protect the kidney from acute rejection. Indeed, the detection of C4d in the liver should be carefully followed after combined liver-kidney transplantation.

Antinucleosome antibodies as a marker of active proliferative lupus nephritis

BACKGROUND

Antinucleosome autoantibodies were previously described to be a marker of active lupus nephritis. However, the true prevalence of antinucleosome antibodies at the time of active proliferative lupus nephritis has not been well established. Therefore, the aim of this study is to define the prevalence and diagnostic value of autoantibodies against nucleosomes as a marker for active proliferative lupus nephritis.

STUDY DESIGN

Prospective multicenter diagnostic test study.

SETTING & PARTICIPANTS

35 adult patients with systemic lupus erythematosus (SLE) at the time of the renal biopsy showing active class III or IV lupus nephritis compared with 59 control patients with SLE.

INDEX TEST

Levels of antinucleosome antibodies and anti-double-stranded DNA (anti-dsDNA) antibodies.

REFERENCE TEST

Kidney biopsy findings of class III or IV lupus nephritis at the time of sampling in a study population versus clinically inactive or no nephritis in a control population.

RESULTS

Increased concentrations of antinucleosome antibodies were found in 31 of 35 patients (89%) with active proliferative lupus nephritis compared with 47 of 59 control patients (80%) with SLE. No significant difference between the 2 groups with regard to number of positive patients (P = 0.2) or antibody concentrations (P = 0.2) could be found. The area under the receiver operating characteristic curve as a marker of the accuracy of the test in discriminating between proliferative lupus nephritis and inactive/no nephritis in patients with SLE was 0.581 (95% confidence interval, 0.47 to 0.70; P = 0.2). Increased concentrations of anti-dsDNA antibodies were found in 33 of 35 patients (94.3%) with active proliferative lupus nephritis compared with 49 of 58 control patients (84.5%) with SLE (P = 0.2). In patients with proliferative lupus nephritis, significantly higher titers of anti-dsDNA antibodies were detected compared with control patients with SLE (P < 0.001). The area under the receiver operating characteristic curve in discriminating between proliferative lupus nephritis and inactive/no nephritis in patients with SLE was 0.710 (95% confidence interval, 0.60 to 0.82; P < 0.001).

CONCLUSIONS

Antinucleosome antibodies have a high prevalence in patients with severe lupus nephritis. However, our data suggest that determining antinucleosome antibodies is of limited help in the distinction of patients with active proliferative lupus nephritis from patients with SLE without active renal disease.

[Hemolytic uremic syndrome following gemcitabine treatment]

Hemolytic uremic syndrome (HUS) in children is classically associated with diarrheas related to the production of a shiga-toxin. HUS occurs among oncologic patients, in relation with the cancer itself, or as a complication of the cytostatic treatment. The physician should be familiar with the triad of HUS (microangiopathic hemolytic anemia, thrombocytopenia and renal failure) and search actively for this pathology in oncologic patient. The treatment is essentially empirical. It includes plasma exchanges, control of blood pressure, hydro-electrolytic balance control with dialysis, if necessary. Blood transfusion should be avoided. Potential mortal complications associated with HUS can be prevented by a rapid diagnosis and a prompt initiation of adequate therapy.

Unusual bleeds, unusual clots

Nine unusual bleeding and clotting disorders (or mimickers of such) are described in the format of case presentations, with focus on clinical history, images and diagnostic tests, followed by a discussion of the disease itself and a summarizing clinical teaching point. The disease entities discussed are acquired factor VIII inhibitor, acquired von Willebrand factor inhibitor, haemophilic pseudotumour, Gardner-Diamond syndrome, coumarin-induced skin necrosis, purple toe syndrome, brachiocephalic vein thrombosis with breast enlargement, and leg swelling due to nephrogenic fibrosing dermopathy and lymphoedema. The publication is meant to demonstrate the fascination of clinical coagulation.

Unusual bleeds, unusual clots

Nine unusual bleeding and clotting disorders (or mimickers of such) are described in the format of case presentations, with focus on clinical history, images and diagnostic tests, followed by a discussion of the disease itself and a summarizing clinical teaching point. The disease entities discussed are acquired factor VIII inhibitor, acquired von Willebrand factor inhibitor, haemophilic pseudotumour, Gardner-Diamond syndrome, coumarin-induced skin necrosis, purple toe syndrome, brachiocephalic vein thrombosis with breast enlargement, and leg swelling due to nephrogenic fibrosing dermopathy and lymphoedema. The publication is meant to demonstrate the fascination of clinical coagulation.

The U.S. Thrombosis and Hemostasis Centers pilot sites program

Venous thromboembolism (VTE) is a common disorder associated with significant morbidity and mortality. Despite important advances in understanding the etiology of VTE, delivery of care to patients with thrombosis and thrombophilia is frequently incomplete and highly variable. A comprehensive model of health care has been used successfully to treat and prevent complications for people with hemophilia and other chronic disorders. The effectiveness of an integrated healthcare model for patients with all coagulation disorders has yet to be evaluated. The Division of Hereditary Blood Disorders of the Centers for Disease Control and Prevention (CDC) is collaborating with eight Thrombosis and Hemostasis Centers (pilot sites) to provide health-related services and conduct research directed toward the reduction or prevention of complications of thrombosis and thrombophilia. The initial objectives of the collaboration are to (1) determine the efficacy of integrated multidisciplinary care and prevention services for people with hemostatic disorders, (2) assess unmet needs for service delivery and identify outreach strategies to improve access to care, (3) develop effective messages aimed at disease management and prevention, and (4) foster the development of training programs to enhance provider skills for the delivery of patient care. To address these objectives, the investigators and CDC have developed and implemented a web-based patient registry to follow prospectively service allocation and patient outcomes. Funding for the program began in October 2001. All eight funded centers are affiliated with U.S. medical schools. Principal investigators at the centers are hematologists (five adult, two pediatric) or cardiologists. Faculty in obstetrics-gynecology, surgery, and multiple other specialties are integral to the model of care at the centers. Other critical components at the centers are clinical laboratory services, training programs, research networks, and education and outreach programs. From August 2003 to March 2006, over 2,600 patients were enrolled in the registry, accounting for a total of more than 5,000 visits to the centers. Immediate goals of the data collection at the centers are to characterize patients receiving care at centers and document the state of health services provided. Long-term goals are to evaluate prospectively clinical outcomes for patients receiving multidisciplinary care and prevention services at centers. The network of data collection across centers will facilitate future collaborative clinical and epidemiologic investigations and enhance collective expertise in hemostasis and coagulation disorders.

CRIT is expressed on podocytes in normal human kidney and upregulated in membranous nephropathy

Complement C2 receptor inhibitor trispanning (CRIT) is a novel human complement regulatory cell surface receptor. It binds the human complement protein C2 and blocks the classical pathway of complement activation, thus protecting the cell against complement attack. CRIT expression in the kidney was analyzed by immunohistochemistry and in situ hybridization. Normal kidney and renal biopsies of patients with different nephropathies were studied. In glomeruli, CRIT protein was expressed only in podocytes. CRIT was also detected in endothelial cells of arterioles and arteries, but not of veins and peritubular and glomerular capillaries. A homogeneous and marked upregulation of CRIT was observed in podocytes in membranous nephropathy (MN). In focal and segmental glomerulosclerosis (FSGS) and minimal change disease, CRIT was downregulated in glomeruli with a loss of the staining in sclerotic lesions of FSGS. No specific changes were observed in the other nephropathies studied. However, podocytes showed in all pathologies a redistribution of CRIT in the cell bodies of 'activated' podocytes. The intensity of mRNA transcription correlated directly with the protein staining in the normal kidney and in MN. These data indicate that CRIT is expressed in the normal human kidney essentially by glomerular podocytes and arterial endothelial cells. The podocyte CRIT expression is upregulated in MN, which is in strong contrast with the known loss of podocyte complement receptor 1. CRIT might represent the last line of defense against complement aggression in MN, and the upregulation of CRIT in 'activated' podocytes might represent a similar self-defense mechanism.

Hormonal factors and risk of recurrent venous thrombosis: the prevention of recurrent venous thromboembolism trial

BACKGROUND

In some but not all studies, men with venous thrombosis had a higher risk of recurrence than women. Information on women with initial hormone-related thrombosis is scant.

OBJECTIVE

We assessed the incidence of recurrent thrombosis by gender, and among women using exogenous hormones or pregnant/postpartum at the time of index thrombosis.

PATIENTS/METHODS

A total of 508 men and women with one or more previous venous thrombosis episodes were observed while participating in a randomized trial of low-intensity warfarin or placebo for 2.1 years. Index thrombosis events during treatment with postmenopausal hormones, oral contraceptives, or during pregnancy, or the puerperium were considered to be hormone-related events.

RESULTS

Among 268 men the 3-year probability of recurrent thrombosis was 18.4% (95% confidence intervals; CI 12.3-24.4). Among 109 women without hormone-related thrombosis, the rate was 15.0% (95% CI 6.3-23.8). Among 129 women with hormone-related thrombosis, the rate was 5.0% (95% CI 1.1-8.9). Adjusting for other risk factors and treatment assignment, women had a 39% lower thrombosis recurrence risk than men: hazard ratio (HR) 0.61 (95% CI 0.34-1.08). Women with hormone-related thrombosis had a 58% lower risk than men: HR 0.42 (95% CI 0.19-0.97); and a 46% lower recurrence risk than other women; HR 0.54 (95% CI 0.19-1.54). Women without hormone-related index events had a recurrence rate similar to men; HR 0.83 (95% CI 0.42-1.66).

CONCLUSIONS

In this trial population, women had a lower risk of recurrent venous thrombosis than men. This difference was explained by a low risk of recurrence among women with hormone-related index thrombosis.

High prevalence of anti-C1q antibodies in biopsy-proven active lupus nephritis

BACKGROUND

Anti-C1q antibodies (anti-C1q) have been shown to correlate positively with systemic lupus erythematosus (SLE) nephritis. Several clinical studies indicated a high negative predictive value, suggesting that active lupus nephritis is rarely seen in patients with no anti-C1q. However, the true prevalence of anti-C1q at the time of active lupus nephritis has not been well established. The aim of this study was to determine prospectively the prevalence of anti-C1q in proven active lupus nephritis at the time of the renal biopsy.

METHODS

In this prospective multi-centre study, we investigated adult SLE patients undergoing renal biopsy for suspected active lupus nephritis. Serum samples were taken at the time of the biopsy and analysed for the presence of anti-C1q in a standardized way. The activity of lupus nephritis was classified according to the renal histology. Biopsies were also analysed for the presence of glomerular IgG, C1q and C3 deposition.

RESULTS

A total of 38 patients fulfilling at least 4/11 American College of Rheumatology (ACR) criteria for the diagnosis of SLE were included. Out of this, 36 patients had proliferative (class II, III or IV) and two had class V lupus nephritis. All but one patient with proliferative lupus nephritis were positive for anti-C1q (97.2%) compared with the 35% of control SLE patients with inactive lupus nephritis and 25% of SLE patients without lupus nephritis ever. All patients were positive for glomerular C1q (36/36) and 37/38 patients had glomerular IgG deposits. Anti-C1q strongly decreased during successful treatment.

CONCLUSIONS

Anti-C1q have a very high prevalence in biopsy-proven active lupus nephritis, thus a negative test result almost excludes active nephritis. The data support the hypothesis of a pathogenic role of anti-C1q in lupus nephritis.

Thalidomide increases thrombin generation in multiple myeloma patients

7602

Background: Numerous reports have demonstrated that the clinical use of thalidomide (THAL) carries a risk for deep venous thrombosis. Only limited investigations into the causative mechanisms for this complication have been conducted. Thrombin generation is a global measurement of hyper or hypocoagulability that has not been used to examine the hypercoagulable state caused by THAL. The aim of this study was to determine if THAL affects thrombin generation in patients with multiple myeloma (MM). Methods: MM patients on and off THAL were recruited. Patients were considered to be “on THAL” if they had been taking the medication for at least three months and “off THAL” if they had not been taking the medication for at least three months. Coagulation tubes of blood containing 3.2% sodium citrate were drawn from each patient. Platelet poor plasma was prepared from these specimens using standard technique. The samples were snap frozen at -70 C and stored until analysis. Thrombin generation was measured using the Calibrated Automated Thrombogram as described by Hemker(Pathophysiol Haemo Thromb 2003;33:4–15) using a microplate fluorometer, the Fluoroskan Ascent from Thermo Electron and the Thrombinoscope software package. The endogenous thrombin potential or ETP (area under the thrombin generation curve) and peak thrombin generation (the maximum release of thrombin per unit of time) were the variables of interest for this study. Results: Twenty seven patients were recruited. Five were excluded from analysis because they were on warfarin or enoxaparin. The normal ETP in females is 1803 ± 241 nM*min and in males is 1745 ± 259 nM *min. Normal peak thrombin generation in females is 318.5 ± 52.9 nM and in males is 293.4 ± 48.5 nM. The t-test was used to compare subjects to normal values.Peak thrombin generation was significantly increased in the 9 subjects taking THAL, 374 ± 10.6 nM (p<0.001) and in the 13 subjects not taking THAL, 352 ± 14.7 nM (p=0.009) when compared to normal values. The ETP was not significantly increased 1818 ± 10.7 nM*min (p=0.69) in subjects not taking THAL. However, ETP was increased in subjects taking THAL, 1939± 90 nM*min and showed a trend toward statistical significance (p=0.10). Conclusions: Thalidomide therapy increases thrombin generation significantly in patients with MM.

[Table: see text]

[Microscopic polyangiitis: an unusual case report]

A 56-year-old woman was referred to our hospital because persistence of fever and inflammatory syndrome after antibiotic treatment for pneumonia. In the past, no special feature. Physical examination revealed only--at first--a pneumonia. Two weeks after, associated with the cough, she developed an acute renal failure. The laboratory revealed an inflammatory syndrome associated with proteinuria, hematuria and anti-neutrophil cytoplasmic antibodies. The CT of thorax shows aspecific infiltrations. The renal biopsy, in the context of the patient, diagnosed an microscopic polyangiitis. All the symptom resolved with the initiation of corticoid and cyclophosphamide treatment.

D-dimer, factor VIII coagulant activity, low-intensity warfarin and the risk of recurrent venous thromboembolism

BACKGROUND

Elevated plasma D-dimer and factor VIII coagulant activity (FVIIIc) may be associated with the risk of recurrent venous thromboembolism (VTE).

OBJECTIVES

To evaluate D-dimer and FVIIIc as risk factors for recurrent VTE and assess the efficacy of extended low-intensity warfarin (target International Normalized Ratio 1.5-2.0) in preventing recurrence by biomarker level.

PATIENTS AND METHODS

In the Prevention of Recurrent Venous Thromboembolism trial, 508 idiopathic VTE patients treated for > or = 3 months with full-intensity warfarin, and who had stopped warfarin for 7 weeks on average, were randomized to low-intensity warfarin or placebo and followed for 2.1 years for recurrent VTE. Prerandomization blood samples were analysed for D-dimer and FVIIIc.

RESULTS

One-third of participants had elevated baseline D-dimer (> or = 500 ng mL(-1)) and one-fourth, elevated FVIIIc (> or = 150 IU dL(-1)). Adjusting for other risk factors, the hazard ratios (HRs) for recurrent VTE with elevated D-dimer or FVIIIc were 2.0 [95% confidence interval (CI) 1.2-3.4] and 1.5 (95% CI 0.8-2.8), respectively. The association of elevated D-dimer with recurrence was larger among patients with one prior VTE (HR 3.2, 95% CI 1.3-8.0) than in patients with more than one event (HR 1.4, 95% CI 0.7-2.2). For patients with one prior VTE on placebo, the annual recurrence incidence was 10.9% with elevated D-dimer and 2.9% with normal values. Low-intensity warfarin was equally effective in recurrence risk reduction in those with normal or elevated biomarkers.

CONCLUSIONS

Among patients with idiopathic VTE, measurement of D-dimer, but not FVIIIc, might be useful for risk stratification. The efficacy of extended low-intensity warfarin therapy did not vary by biomarker level.

De novo concurrent papillary renal cell carcinoma and angiomyolipoma in a kidney allograft: evidence of donor origin

In the general population, renal cell carcinoma (RCC) is a relatively common neoplasm; however, the papillary RCC subtype is infrequent and represents only 10 to 15% of all RCC. Angiomyolipoma is a well-known common benign tumor. The occurrence of RCC in association with angiomyolipoma is a rare event, with only approximately 50 cases reported in the nontransplantation setting. In transplant recipients, RCC can develop in native kidneys, but its occurrence "de novo" in the renal allograft is very rare with an estimated incidence of less than 0.5%. We report here the case of a 39-year-old woman who underwent cadaveric renal transplantation in 1990. No lesion was observed in the allograft during the pre- and perioperative period or on early postoperative ultrasounds. No graft rejection occurred under a standard triple immunosuppressive therapy. Thirteen years later, during a routine ultrasonography, 2 solid masses were discovered in the allograft, both of them richly vascularized. She underwent allograft nephrectomy and the histologic findings revealed that one of the tumors was a chromophilic (type 1) papillary RCC (2.5 cm in diameter) and the other, an angiomyolipoma (1.5 cm). Microsatellite analysis of the allograft, as compared with the recipient peripheral blood leukocytes, demonstrated that the 2 tumors (1 malignant and 1 benign) were of donor origin. To our knowledge, this is the first report of de novo concurrent papillary RCC and angiomyolipoma in a renal allograft.

[Clinical and genetics aspects of Alport syndrome]

Microscopic haematuria of glomerular origin, without known aetiology, should raise the suspicion of Alport Syndrome IASI in children as well as in adults. The genetic mutations causing AS lie in the genes encoding for the alpha3, alpha4 and alpha5 chains of the collagen type IV, the main constituent of glomerular basement membranes (GBM). The various mutations and modes of transmission of the disease account for the heterogeneous clinical presentations. No specific treatment of AS is currently available. However, a better understanding of the GBM's ultrastructure, in particular of type IV collagen, will hopefully enable the identification of novel therapeutic targets.

Humoral rejection of organ allografts

In recent years, the deleterious clinical consequences of recipient de novo alloantibody production against HLA antigens from human organ allografts have been extensively investigated. In kidney transplantation, the identification of the complement C4d fragment in peritubular capillaries as a specific marker for humoral rejection has helped to define and characterize distinct clinical alloantibody-mediated syndromes. This knowledge is relevant for patient management as new therapeutic strategies to remove and control anti-donor antibody production, particularly in the setting of acute humoral rejection, have been reported. For recipients of nonrenal organ allografts such as heart transplant recipients, de novo anti-HLA alloantibody may also be important, although more studies are needed before clear guidelines can be proposed.

[IgA nephropathy: what you have need to know in 2005]

Although considered as a benign glomerulopathy, IgA nephropathy (IgAN) is now a well-known cause of end-stage renal disease (ESRD). Fifty percent of people suffering from IgAN developp renal insufficiency and 20 to 30% may reach ESRD after 20 to 25 years of evolution. ACEI is indicated to obtain a thigh control of blood pressure and to reduce proteinuria. Corticosteroids alone or in association with immunosuppressants are indicated for agressive, proliferative form of the disease or when there is an unfavorable outcome despite symptomatic treatment.

Phase I study of a novel recombinant human soluble thrombomodulin, ART-123

BACKGROUND

Anticoagulants are often given for extended periods of time to patients at high risk for venous thromboembolism, such as after orthopedic surgery. Daily subcutaneous (sc) injections can be inconvenient to the patient. A long-acting anticoagulant requiring less frequent dosing could make treatment more acceptable. Thrombomodulin is a natural anticoagulant that activates protein C, which leads to inactivation of factor (F)Va and FVIIIa and decreased thrombin formation. Recombinant human thrombomodulin is a novel anticoagulant with a long half-life in animal models.

METHODS AND RESULTS

This phase I study examined pharmacokinetics, pharmacodynamics, and safety of recombinant human soluble thrombomodulin (ART-123) after administration of doses between 0.02 and 0.06 mg kg(-1) body weight intravenously (iv), and between 0.02 and 0.45 mg kg(-1) sc in 55 healthy volunteers. The plasma half-life was 2-3 days after sc injection of various single doses. Plasma ART-123 levels estimated to be needed for prevention of thrombus formation in humans were maintained for at least 6 days after single sc injection of 0.30 and 0.45 mg kg(-1) ART-123. Antithrombotic activity with these doses was demonstrated by achieving prothrombinase inhibition of more than 80% for more than 6 days after administration. No major bleeding occurred. Pharmacodynamic modeling revealed that adequate antithrombotic ART-123 levels can be achieved for 6 days with one dose of 0.45 mg kg(-1) ART-123, and for 12 days with 2 doses of 0.30 mg kg(-1), given 5 days apart.

CONCLUSIONS

Recombinant human soluble thrombomodulin (ART-123) has a long half-life after sc injection and is well tolerated, making it a suitable agent to be tested in clinical thromboprophylaxis trials.

Knowledge and educational needs of individuals with the factor V Leiden mutation

BACKGROUND

Genetic testing for factor (F)V Leiden is widely performed in an effort to prevent thrombosis-related morbidity. The implications of a positive test for patients' health perception and the extent of patients' understanding of results are not known.

OBJECTIVES

This study examined patient experience of genetic testing for FV Leiden.

PATIENTS AND METHODS

The study was a cross-sectional, mailed survey of 110 patients who tested positive for the FV Leiden gene mutation at an academic medical center between 1995 and 2001. Patient knowledge about FV Leiden, satisfaction with available information, and psychosocial reactions to testing were assessed and the influence of demographic and clinical characteristics on outcome measured.

RESULTS

The magnitude of thrombosis risk associated with FV Leiden was incorrectly estimated by 79% of participants. Many patients (64%) stated that they had not been given much information about FV Leiden and 68% still had many questions. Most patients (53%) felt that their healthcare providers do not understand FV Leiden. Patients who had been seen by a hematologist or in a specialized thrombosis clinic were more knowledgeable and had less information need. Most patients (88%) were glad to know genetic test results, despite negative psychosocial implications such as increased worry (43%).

CONCLUSIONS

Knowledge of genetic status increases awareness of thrombosis risk among patients, but magnitude of risk is often overestimated. Affected individuals indicate that there is a lack of available information about FV Leiden and that additional educational resources are needed.