-Yin Chen

Proteomic analysis of peritoneal dialysate fluid in patients with dialysis-related peritonitis.

The prognosis of uremia patients on continuous ambulatory peritoneal dialysis (CAPD) is related to frequent peritonitis rate. Frequent peritonitis will lead to peritoneum failure, making CAPD unfeasible. We have performed proteomic profiling of peritoneal dialysis effluent samples from a cross-section of CAPD patients with and without peritonitis in order to identify biomarkers of peritonitis. We performed 2D gel electrophoresis and surface-enhanced laser esorption/ionization time of flight mass spectrometry (SELDI-TOF MS) on peritoneal dialysis effluent from 16 subjects with peritonitis. A genetic algorithm search of principal component space revealed a group of a peak distinguishing peritonitis-positive subjects, with mass/charge (m/z) values of 11,117.4. Our analyses identified the peak at m/z 11,117.4 with an accuracy of 95% for classifying peritonitis. Mass spectrometric analysis of peritonitis PDE samples identified the 11,117.4 protein as β2-microglobulin (B2M). Using an unbiased protein profiling approach, we have validated previously reported findings of B2M as a biomarker associated with CAPD peritonitis. Prospective studies are warranted to establish additional biomarkers that would be predictive of peritoneal dialysis peritonitis. Besides, extending the study to a larger number of patients with subgroup analyses may yield additional information of the peritoneal dialysate proteins in association with dialysis adequacy, residual renal function, nutritional status, and risk of peritoneal infection.

Valproate-Induced Hyperammonemic Encephalopathy Treated by Hemodialysis

Valproate-induced hyperammonemic encephalopathy is an unusual but serious complication that may occur in people with normal liver-associated enzyme levels, despite normal therapeutic doses and serum levels of valproate. Here, we describe an adolescent girl who had absence seizure and complained about progressive dizziness and general malaise several days after restarting valproate. Then, she presented vomiting and decreased consciousness three weeks after valproate use. Notably, her serum ammonia level was five times the upper limit of normal (184 μmmol/L), with normal liver-associated enzyme and supra-therapeutic valproate level. EEG showed continuous generalized slowing. The tandem mass analysis revealed carnitine deficiency. Consciousness improved after emergent hemodialysis. Ammonia level and EEG also returned to normal. Possible mechanisms, risk factors and the treatments of valproate-induced hyperammonemic encephalopathy are described. Physicians should consider this possibility when consciousness disturbance occurs in patients treated with valproate.

Biopsy Proven Acute Tubular Necrosis Associated with Vancomycin in a Child: Case Report and Literature Review

Vancomycin-related nephrotoxicity typically manifests as acute tubulointerstitial nephritis. The drug does appear, however, to increase the nephrotoxicity of concurrently administered aminoglycosides. The extent of direct tubular toxicity attributable to vancomycin, especially in the absence of aminoglycoside treatment, does not appear to have been previously described. We report a case of biopsy-proven acute tubular necrosis secondary to vancomycin toxicity in a 13-year-old boy where there was no likely alternate explanation for toxic or ischemic injury. No hemodialysis was required, and the patient made a full recovery with subsequently regained renal function.

Sjogren's Syndrome Complicated with IgA Nephropathy and Leukocytoclastic Vasculitis

We report a case of primary Sjögrens syndrome (SS) with cutaneous leukocytoclastic vasculitis and IgA nephropathy. The accurate diagnosis of SS was established based on objective signs and symptoms of ocular and oral dryness, a characteristic appearance of a biopsy sample from a minor salivary gland, and the presence of anti-SS-A autoantibody. A second autoimmune disorder was not present, so the diagnosis of primary SS was established. A histologic finding of skin biopsy of purpuric lesion was typical for leukocytoclastic vasculitis. Renal biopsy was performed for nephrotic range proteinuria. The pathologic finding of renal biopsy was IgA glomerulonephritis with crescent formation. The patient was treated with small doses of glucocorticoids and maintenance hemodialysis. Leukocytoclastic vasculitis is one of the most characteristic extraglandular manifestations of SS. However, IgA nephropathy associated with SS and leukocytoclastic vasculitis is a rare finding. SS patients with glomerulonephritis present a more diverse outcome, even requiring hemodialysis. Therefore, renal biopsy is warranted in SS with glomerulonephritis and systemic vasculitis.

Hepatitis C virus-associated type II mixed cryoglobulinemia vasculitis complicated with membranous proliferative glomerulonephritis.

Essential mixed cryoglobulinemia (type II) has turned out to be secondary to hepatitis C virus (HCV) infection in the large majority of patients. Interferon might be anticipated to be effective only in HCV-associated cryoglobulinemias. We found that interferon was highly effective in an HCV-positive patient with true essential type II mixed cryoglobulinemia. The patient presented with symptomatic cryoglobulinemic vasculitis without underlying immunologic, infectious, or neoplastic diseases. Tests for HCV viremia, a reverse-transcriptase–polymerase-chain-reaction (RT-PCR) assay, and anti-HCV antibodies (third-generation assays) were positive before therapy. The patient had severe cryoglobulinemic vasculitis with purpura, peripheral neuropathy, and membranous proliferative glomerulonephritis. The cryocrit before therapy was 6 percent in the patient. Recombinant interferon alfa-2a (Roferon-A, Hoffmann–LaRoche, Basel, Switzerland) was administered at a dose of 3 million units per day for three months and 3 million units every other day for the subsequent nine months, a protocol adopted for HCV-associated cryoglobulinemia. The patient had a complete clinical response, with the disappearance of serum cryoglobulins and all signs of cutaneous vasculitis and with the normalization of kidney-function results and urinary values in the patient with nephropathy. The patient has remained in complete remission for more than one year since the withdrawal of therapy. True essential mixed cryoglobulinemia with HCV infection complicated with glomerulonephritis represents a therapeutic challenge.

Renal Carcinosarcoma: Case Report and Review of Literature

Carcinosarcoma is a malignancy that occurs very rarely in the renal pelvis, and only a very limited number of cases has been documented. These tumors are composed of both malignant mesenchymal and epithelial elements. Unlike the cases described so far, this carcinosarcoma of the renal pelvis was characterized by quick recurrence, following complete surgical resection. Carcinosarcomas of the renal pelvis are known to be rapid in progression and associated with a poor prognosis. They usually metastasize soon after surgery, but very little information is available on the histologic types that characterize the recurrent tumors. We presented a histologically proven case of renal carcinosarcoma extending from renal pelvis. Convalescence was uneventful, and fifteen months after the operation, he is alive with no recurrence or metastasis. If a rapidly growing tumor is detected that seems to originate from the kidney with extension to ureter and bladder, carcinosarcoma should be included in the differential diagnosis.

Paraneoplastic Polymyositis Associated with Crescentic Glomerulonephritis

A female concurrently developed polymyositis (PM), lung cancer, and nephrotic range proteinuria. Renal biopsy revealed crescentic glomerulonephritis. Pathology of lung cancer was proved to be adenocarcinoma. After surgical treatment of lung cancer, the symptoms of PM-associated crescentic glomerulonephritis disappeared. PM is associated with a higher risk of malignancy, though renal involvement in patients with PM is thought to be uncommon. In patients with PM, there have been few reports concerning the coexistence of glomerular disease, including crescent glomerulonephritis. Herein we report a case of crescentic glomerulonephritis-associated PM that was successfully treated after the surgical removal of lung cancer. We consider that such association of PM and crescent glomerulonephritis is rare in adults. Careful evaluation of underlying malignancy is important. The definite treatment is adequate management of underlying malignancy.

Continuous hemodiafiltration in the treatment of hyperammonemia due to methylmalonic acidemia.

Methylmalonic academia (MMA) is a rare inborn error of branched-chain amino acid metabolism. Therapy consists of a special formulated protein diet, carnitine supplementation, and emergent detoxification during acute decompensation. Continuous hemodiafiltration is a modality choice to treat acute metabolic decompensation in inborn error of metabolism. We report the successful use of continuous hemodiafiltration in the management of acute decompensation in patients with methylmalonic academia. Three male patients were diagnosed with methylmalonic academia with the initial presentation of hyperammonemia. Continuous hemodiafiltration was utilized to treat acute decompensation of metabolic crisis. This approach results in a rapid reduction of systemic toxin levels. Continuous hemodiafiltration should be considered as a treatment modality for symptomatic neonates with MMA where hemodialysis is not feasible.

Outcome Prediction for Critically Ill Children with Acute Renal Failure Requiring Continuous Hemofiltration

Continuous hemofiltration has been used with increasing frequency for treating volume overload and acute renal failure in critically ill, hemodynamically unstable pediatric patients. This retrospective report investigates continuous hemofiltration in pediatric patients, and their survival rate. Sixty children treated between 1999 and 2001 with a diagnosis of acute renal failure and requiring continuous hemofiltration were admitted to this study to determine if pediatric risk of mortality III (PRISM III) scores were an accurate prediction of mortality. PRISM III scores were calculated on the day continuous hemofiltration commenced; mean PRISM III scores of nonsurvivors were significantly higher than mean scores of survivors. PRISM III scores may be a useful indicator of outcome in children receiving continuous hemofiltration.

Influenza A(H1N1) Infection with Rhabdomyolysis and Acute Renal Failure-A Case Report

Pandemic 2009 influenza A (H1N1) is an emerging disease first reported in April, 2009. Previous studies have pointed out that patients with pneumonia and respiratory failure arising from pandemic H1N1 may have abnormal laboratory examination results, including elevated creatine kinase (CK) levels. We report a patient with pandemic H1N1 infection who developed mild rhabdomyolysis and acute kidney injury (AKI). Rhabdomyolysis is uncommon but potentially life-threatening. We present a 33-year-old patient who developed rhabdomyolysis following pandemic influenza A (H1N1/09) infection. Although pneumonia and acute respiratory distress syndrome are the most common severe complications of H1N1/09 infection, clinicians should be aware that H1N1/09 infection may be complicated by rhabdomyolysis.