Characterization of hypersensitivity reactions to polysulfone hemodialysis membranes.

BACKGROUND: In recent years, cases have been reported in which unexpected systemic hypersensitivity reactions occurred in patients dialyzed with polysulfone- or polyethersulfone-biocompatible membranes in the absence of other risk factors. The pathomechanisms involved in these reactions are largely unknown. OBJECTIVE: To characterize hypersensitivity reactions to polysulfone hemodialysis using clinical and laboratory data and to identify biomarkers suitable for endotype identification and diagnosis. METHODS: We prospectively collected data from 29 patients with suspected hypersensitivity reactions to polysulfone hemodialysis membranes. Clinical laboratory parameters such as tryptase, blood cell counts, and complement levels were recorded. Acute samples were obtained from 18 cases for the ex vivo assessment of basophil activation by flow cytometry analysis of CD63, CD203, and FcεRI cell membrane expression. Serum cytokines and anaphylatoxin concentrations were evaluated in 16 cases by Luminex and cytometric bead array analysis. RESULTS: Tryptase was elevated during the acute reaction in 4 cases. Evidence of basophil activation was obtained in 10 patients. Complement activation was found in only 2 cases. However, C5a serum levels tended to increase during the acute reaction in those patients with hypoxemia. Significantly higher serum levels of interleukin-6 were observed during the acute reactions to polysulfone hemodialysis (P = .0103). CONCLUSION: Based on biomarker analysis, various endotypes were identified, including type I-like (with the involvement of mast cells or basophils), complement, and cytokine (interleukin-6) release-related reactions, with some patients showing mixed reactions. Further research is needed to unravel the exact mechanisms involved in the activation of these cellular and molecular pathways.

Massive hemoptysis following Rasmussen's aneurysm: a case report

Rasmussen's aneurysm (RA) is a pseudoaneurysm of a pulmonary artery (AP), adjacent to or within a tuberculous cavity, appearing in 5% of these lesions. Its rupture might provoke massive hemoptysis (MH) with a near 50% mortality. The aim of this article is to report a case of massive hemoptysis following Rasmussen's aneurysm. 52-year-old man with recent history of hospita-lization due to pneumonia associated to influenza A and decompensated hyperthyroidism, pre-sents outpatient chest radiograph with signs of hyperinflation and scarring apical opacities, the patient returned to the hospital due to sharp pain of left hemi thorax during inspiration accom-panied with bloody sputum, asthenia and non-quantified weight loss. He evolves to frank MH, requiring endotracheal intubation managed in the intensive care unit (ICU). Chest computed tomography (CT) reported ground-glass opacity, nodules with a tendency to cavitation, tree-in-bud pattern in agreement with inflammation and infection, active TB is considered, and truncus of PA with vascular lesion suggestive of aneurysm dependent on pulmonary circulation, possibly RA. Fibrobronchoscopy reported signs of old and recent bleeding of left bronchial tree, probably of the lingula, blood clots in right bronchial tree. Molecular study and TB cultures was negative. Endovascular procedure with arteriography was carried out, revealing amputation of left distal segmental PA carrying the pseudoaneurysm with complete regression, discarding embolization RA It must be considered among the differential diagnoses of MH, especially on patients with pulmonary TB complications, such as the reported case. Due to its associated increased morta-lity, once RA is identified, it must be either endovascularly or surgically eradicated.

Idiopathic multicentric Castleman's disease, infrequent cause of Lupus-like: case report

Castleman's disease (CD) or angiofollicular lymph node hyperplasia includes a heterogeneous mix of reactive lymphoproliferative processes with well-defined histological features. However, they differ in their localization patterns, clinical expression and etiopathogenesis. There are 4 types, one of them is the multicentric CD that is not associated with any viruses and has re-cently been called idiopathic MCD (iMCD). iMCD is a lymphoproliferative disorder with specific histopathological characteristics, more than one region of affected lymph nodes and absence of infection associated to human herpesvirus 8 and human immunodeficiency virus (HIV). iMCD covers multiple differential diagnoses and might simulate autoimmune diseases such as syste-mic lupus erythematosus. The aim of this article is to report the case of a patient with Castle-man's disease and lupus-like presentation. We present the case of a 38-year-old man without morbid history, who presented lumbago, fever, diaphoresis and asthenia with two months of evolution, associated to bilateral cervical adenopathies. General examinations result negative, antinuclear antibodies at a dilution of 1/640 were positive, and extractable nuclear antigens were positive suggesting moderate Systemic Lupus Erythematosus (SLE) plus secondary Sjö-gren's. Methylprednisolone and Hydroxycloroquine boli were thus initiated. The patient evolved with anasarca, severe anemia, acidosis, polyserositis and multiple mediastinal adenopathies. Immunoglobulin and cyclophosphamide were thus initiated. He later presented fever, throm-bocytopenia and nephrotic syndrome. Biopsy of cervical lymph node reported lymphadenitis with polyclonal plasmacytosis and concentric lymphoid hyperplasia, in agreement with iMCD. Treatment with Rituximab was initiated, which led to the favorable evolution of the patient. iMCD is a systemic inflammatory disease, its presentation corresponds to a constitutional syndrome resulting in a wide differential diagnosis. Every time suspicious adenopathies appear, they must be biopsied since this might lead to a definitive diagnosis

Study of the expression of cathepsins in histological material from pancreatic lesions.

BACKGROUND AND AIMS: To assess the expression levels of cathepsins in malignant and premalignant lesions. METHODS: We retrospectively included patients who underwent pancreatic surgery on pancreatic solid or cystic masses. The expression of cathepsin H, L, B and S was determined in both types of samples. Lesions were divided into three categories: malignant (pancreatic adenocarcinoma and malignant mucinous neoplasms), premalignant (mucinous neoplasms) and benign (other lesions). RESULTS: Thirty-one surgical resection samples were studied. The expression of cathepsins was significantly higher in malignant lesions than in premalignant and benign lesions (H 75%, 27%, 37% p = 0.05; L 92%, 36%, 37% p = 0.011; B 83%, 36%, 62% p = 0.069; S 92%, 36%, 25% p = 0.004, respectively). CONCLUSIONS: Cathepsins are overexpressed in histological samples of malignant lesions compared to premalignant and benign lesions. However, the expression of cathepsins is similar in both premalignant and benign lesions.

Real anal leiomyoma: a case report.

Leiomyoma of the rectum and anal canal is an unusual benign mesenchymal neoplasm that originates from smooth muscle cells. We describe the clinical presentation, MRI findings, and surgical treatment of a rare case of perianal leiomyoma confirmed by immunohistochemistry. We also report a review of the world's literature on the subject.

Direct intracystic biopsy and pancreatic cystoscopy through a 19-gauge needle EUS (with videos).

BACKGROUND: Histologic diagnosis of cystic pancreatic lesions (CPLs) is often difficult because of the low sensitivity of FNA and brush cytology. OBJECTIVE: To discover whether obtaining biopsy samples from the cystic wall could increase the diagnostic yield of these lesions. DESIGN: A pilot study including 2 patients with CPLs. SETTING: Endoscopy unit in a tertiary-care hospital. PATIENTS: Two women with CPLs located at the pancreatic head. INTERVENTIONS: On EUS, biopsy forceps and a SpyGlass fiberoptic were passed through a 19-gauge needle to visualize and obtain samples from the cystic wall. MAIN OUTCOME MEASUREMENTS: The histologic assessment was based on the obtained biopsy samples. RESULTS: Both CPLs were considered to be mucinous cystoadenomas, because mucinous-like cylindric epithelium without cellular atypia was observed. LIMITATIONS: Pilot study. CONCLUSIONS: Obtaining biopsy samples from the wall of a CPL is now feasible. It represents a significant advantage in the diagnostic yield of this type of lesion.

Tacrolimus/mycophenolate mofetil-based immunosuppression in aged kidney transplant. A prospective study.

BACKGROUND: At the moment, controversy has arisen about immunosuppression in aged kidney transplant recipients. We present our results on the efficacy and safety of induction treatment based on tacrolimus (FK506) and mycophenolate mofetil (MMF). MATERIAL AND METHOD: We performed 72 transplants in patients of 60 years or older. Induction treatment consisted on (FK 506) 0.1 mg/kg/day and MMF 2 gr/day. Antilymphocyte serum was administered with delayed graft function. A total of 54 patients received kidneys from donors over 60 years old. RESULTS: Cold ischemia time was 16.4 h (S=5.7). Delayed graft function occurred in 35 patients (48.6%). Acute rejection was observed in nine patients (12.5%). Opportunistic infections were found in 19 patients (26.4%). Seven patients died due to sudden death (1), acute myocardial infarction (1), stroke (1), infection (3), and neoplasm (1). At 1, 2, and 3 years, serum creatinine was 145, 163, and 156 mmol/l; patient survival 93%, 90%, and 90%; graft survival 93%, 90%, and 87%; and death-censored graft survival 100%, 100%, and 97%, respectively. CONCLUSION: These immunosuppressive guidelines appear to be efficacious and safe in kidney transplant in elderly recipients.

Endothelial nitric oxide synthase gene polymorphism in dialysis patients.

Nitric oxide is an important factor in the regulation of vasodilator tone. In vascular cells, NO is synthesized by endothelial nitric oxide synthase, a key enzyme of the endogenous vasodilator system. Some studies have described the interaction between NO and the other factors that promote vasodilatation in vascular smooth muscular cells. Some of those factors are angiotensin-converting enzyme (ACE), transforming growth factor beta (TGF beta), and endothelial oxide nitric synthase (eNOS). Polymorphism that can alter the expression or the function of the eNOS protein has been identified in the eNOS gene in the promoter and codification zones. We studied the Glu298Asp variant of the eNOS gene in 52 hemodialysis (HD) patients, 22 peritoneal dialysis (PD) patients, and 93 healthy controls. Identification of the Glu298Asp variant in exon 7 was performed by enzymatic amplification and restriction fragment length polymorphism (RFLP) analysis. The frequencies of eNOS genotypes in the control group were GG, 39.8%; GT, 43%; and TT, 17.2%. In HD patients, the frequencies were GG, 40.3%; GT, 38.7%; and TT, 21.7%. In PD patients, they were GG, 41.6%; GT, 50%; and TT, 8.6%. No significant differences were seen between the control group and the dialysis patients, or between the HD and the PD patients.

Protein oxidative stress in dialysis patients.

Inflammatory status is observed in patients with chronic renal failure (CRF). The relationship between oxygen free radical production and dialysis could play an important role in protein oxidation. Carbonyl protein plasma level is an important tool in the study of protein stress, and it is related to the arterial intima thickness in the atherosclerosis process. We studied protein oxidative stress in 21 peritoneal dialysis (PD) patients and 42 hemodialysis (HD) patients as compared with 32 undialyzed patients with CRF. Carbonyl protein plasma levels were measured in nanomoles per milligram protein by the ELISA method (Winterbourn et al). Dialysis patients had a higher protein carbonyl content than did CRF patients (0.1265 +/- 0.04 nmol/mg vs. 0.1594 +/- 0.03 nmol/mg, p < 0.0002). Patients on PD had a lower level than patients on HD (0.1452 +/- 0.03 nmol/mg vs. 0.1665 +/- 0.04, p < 0.004). Glucose administration in PD is known to be able to increase glucose degradation products (GDPs) and advanced glycosylation end-products (AGEs) with high carboxylic and oxidative stress. In our study, the carbonyl protein level was higher in HD patients than in PD patients, perhaps because more protein oxidative stress is associated with hemodialysis technique or because the PD patients had greater residual renal function.