Granulocyte and monocyte CD11b expression during plasma separation is dependent on complement factor 5 (C5) - an ex vivo study with blood from a C5-deficient individual.

The aim of the study was to investigate the role of complement factor 5 (C5) in reactions elicited by plasma separation using blood from a C5-deficient (C5D) individual, comparing it to C5-deficient blood reconstituted with C5 (C5DR) and blood from healthy donors. Blood was circulated through an ex vivo plasma separation model. Leukocyte CD11b expression and leukocyte-platelet conjugates were measured by flow cytometry during a 30-min period. Other markers were assessed during a 240-min period. Granulocyte and monocyte CD11b expression did not increase in C5D blood during plasma separation. In C5DR samples granulocytes CD11b expression, measured by mean fluorescence intensity (MFI), increased from 10481 ± 6022 (SD) to 62703 ± 4936, and monocytes CD11b expression changed from 13837 ± 7047 to 40063 ± 713. Granulocyte-platelet conjugates showed a 2.5-fold increase in the C5DR sample compared to the C5D sample. Monocyte-platelet conjugates increased independently of C5. In the C5D samples, platelet count decreased from 210 × 109 /L (201-219) (median and range) to 51 × 109 /L (50-51), and C3bc increased from 14 CAU/mL (21-7) to 198 CAU/mL (127-269), whereas TCC formation was blocked during plasma separation. In conclusion, up-regulation of granulocyte and monocyte CD11b during plasma separation was C5-dependent. The results also indicate C5 dependency in granulocyte-platelet conjugates formation.

[Bisalbuminemia: A Rare Variant of Albumin]. / Bisalbuminémia: Uma Variante Rara da Albumina.

INTRODUCTION: Bisalbuminemia is a qualitative disorder of albumin and it is defined by the coexistence in the same individual of two types of serum albumin with different electrophoretic mobility. There are two forms: hereditary and permanent, or acquired and transient. CASE REPORT: Girl, 17-years-old, referenced to the hospital consult after incidental finding of bisalbuminemia detected in plasma protein electrophoresis performed within the investigation of diminished muscular tone in the lower limbs. Physical examination was normal. Secondary causes of bisalbuminemia were excluded. Later, it was confirmed the same disorder in plasma protein electrophoresis performed to her 14-years-old brother and mother. DISCUSSION: We describe a rare case of hereditary bisalbuminemia in a portuguese family. In general, this condition shows no pathological significance, however it is of interest to the clinicians the knowledge of this analytic change for better orientation of their patients.

Introdução: A bisalbuminémia é uma alteração qualitativa da albumina e define-se pela coexistência no mesmo indivíduo de dois tipos de albumina sérica com mobilidade eletroforética diferente. Existem duas formas: hereditária e permanente ou adquirida e transitória. Caso Clínico: Adolescente, sexo feminino, 17 anos, referenciada à consulta hospitalar por achado incidental de bisalbuminémia detetada na eletroforese de proteínas plasmáticas, realizada em contexto de noção de diminuição da força dos membros inferiores. O exame objetivo não apresentava alterações. Foi excluída causa secundária de bisalbuminémia. Posteriormente, confirmou-se a mesma alteração em eletroforese de proteínas plasmáticas realizada ao irmão de 14 anos e à mãe. Discussão: Descrevemos um caso raro de bisalbuminémia hereditária numa família portuguesa. Em geral não apresenta significado patológico, no entanto tem interesse para o clínico o conhecimento desta alteração analítica para melhor orientar e esclarecer os seus doentes.

Bisalbuminaemia due to novel mutation at a critical residue involved in recycling; Albumin Lyon (510His→Arg).

OBJECTIVES: To define the underlying cause of bisalbuminaemia in an individual presenting with spontaneous venous thrombosis. METHOD: Plasma was examined by electrospray time-of-flight mass spectrometry (TOF MS) to assess albumin mutations and to quantify variant expression level. Tryptic peptide mapping and DNA sequencing were used to precisely define the mutation. RESULTS: Whole protein MS indicated a 19Da increase in the mass of 50% of the albumin molecules suggesting a His→Arg substitution. A novel heterozygous 510His→Arg mutation was identified by peptide mass mapping and confirmed by DNA sequencing of exon 12 of the albumin gene. CONCLUSION: The nature and location of the mutation suggest it would have no direct influence on haemostasis through altered warfarin binding or increased fibrinogen attachment and it appears to be incidental to the thrombotic phenotype. However the highly conserved His510 residue is recognised as being of critical importance in albumin recycling through interaction with its savaging neonatal Fc receptor. The normal albumin level of 41.1g/l and the coequal expression of albumin Lyon demonstrate that the conservative 510His→Arg substitution does not interfere with the pH dependant capture and release of albumin by the receptor.

Fever of unknown origin (FUO) in an immunocompetent adult due to cytomegalovirus (CMV) with polyclonal gammopathy.

Fever of unknown origin (FUO) may be due to infection, malignancy, collagen vascular/inflammatory disorders, or other causes. Cytomegalovirus (CMV) infection is a rare cause of FUO in immunocompetent adults. We present a case of FUO due to CMV in an immunocompetent adult with polyclonal gammopathy on serum protein electrophoresis (SPEP).

Tissue zinc levels in a child with hypercalprotectinaemia and hyperzincaemia: A case report and a review of the literature.

BACKGROUND: A girl suffering from a rare syndrome of unknown aetiology, termed hypercalprotectinaemia, was evaluated for tissue zinc status, because calprotectin is a protein which chelates Zn at multiple binding-sites, which might have affected the distribution of Zn in her body. METHODS: Measurement of serum, urine, hair and nail zinc (Zn) concentration, complemented with measurement of total Zn in ultrafiltrates of plasma. RESULTS: Her serum Zn concentration was 105-133 µmol/L. Zn levels in her hair (102 µg/g), nail (90 µg/g) and urine (3-12 µmol/L; 20-80 µg/dL) were all at the lower end of the reference intervals described in the sparse literature. Zn concentrations in ultrafiltrates of plasma were below the detection limit (<100 nmol/L). Thus, the elevated serum Zn did not translate into a similarly increased level of Zn in any of the tissues tested, nor in free Zn concentrations. Instead it appeared to be a result of Zn being chelated to binder proteins, most probably calprotectin. CONCLUSION: Her grossly elevated serum calprotectin concentration is probably able to raise circulating total Zn concentrations without raising ionized concentrations, but this Zn remains confined to the circulating blood as well as to excreted body fluids, particularly faeces.

Detection and characterization of variant and modified structures of proteins in blood and tissues by mass spectrometry.

Some variant proteins cause diseases, and some diseases result in increases of proteins with abnormally modified structures. The detection, characterization, and estimation of the relative amounts of protein variants and abnormally modified proteins are important for clinical diagnosis and for elucidation of the mechanisms of the pathogenesis of diseases. Analysis of the covalent structures of proteins using matrix-assisted laser desorption time-of-flight mass spectrometry (MALDI-TOF-MS) and liquid chromatography-electrospray ionization MS (LC-ESI-MS), which had been developed by the early 1990s, have largely replaced analyses by conventional protein chemistry. Here, we review the detection and characterization of hemoglobin variants, HbA1c measurement, detection of carbohydrate-deficient transferrin, and identification of variants of transthyretin (TTR) and Cu/Zn-superoxide dismutase (SOD-1) using soft ionization MS. We also propose the diagnostic application of the signals of modified forms of TTR, that is, S-sulfonated TTR and S-homocysteinyl TTR. The relative peak height ratio of the abnormal/normal components gives valuable information about the instability of variants and enables the detection of unstable Hb subunits or thalassemia heterozygotes. We found unique modified structures of TTR that suggested changes in amyloid fibrils.

[Aetiological spectrum of hyperferritinemia]. / Spectre étiologique des hyperferritinémies.

UNLABELLED: Serum ferritin levels may be increased in many conditions: renal diseases, liver diseases, human immunodeficiency virus infection. The purpose of this study was to assess the aetiological spectrum of high serum ferritin levels in a 1200-bed university hospital, to compare our results with the data already published and to assess a potential association between aetiology and ferritin levels. PATIENTS AND METHODS: Patients with a serum ferritin level higher than 600 microg/l were retrospectively included between 15 November 2003 and 15 January 2004, and their medical records were reviewed. RESULTS: Ninety-eight patients (38 women and 60 men; median age: 59,5 years [19-92]) were recruited in departments of hepatology and gastroenterology (22%), haematology (14%) and internal medicine (18%). Diagnosis performed were: non-HIV systemic infections (23,8%), haematological diseases (16,1%), alcoholism (11,2%) and malignancies (9,8%). Dialysed chronic renal failure, liver diseases, haemochromatosis and systemic inflammatory diseases counted for 4.2 to 5.2% of cases. Serum ferritin level lied between 600 and 1000 microg/l for 50 patients, between 1000 and 1500 microg/l for 24, and over 1500 microg/l for 24. There was no significant difference between the three groups as regards the etiological distribution. DISCUSSION: In our study, chronic renal failure was not a major cause of high ferritin level: this is probably due to the current use of erythropoietin, which has decreased the use of blood transfusions. The two major aetiology of hyperferritinemia were non-HIV infections and malignancies.

[Dysalbuminemia]. / Les dysalbuminémies.

Albumin is the major circulating protein. It plays a fundamental role maintaining intra-vascular oncotic pressure and carrying many endogenous and exogenous substances. Variations of plasma albumin levels can be physiologic or pathologic and both qualitative and quantitative (more frequent) disorders are regrouped under the name "dysalbuminemia". Although hypoalbuminemia are frequent, analbuminemia exists but is a rare disease. Qualitative disorders, mainly bisalbuminemia, are benign. Detected fortuitously on sera protein electrophoresis, bisalbuminemia could be genetically transmitted, it will then be permanent, or acquired and then be transient. This article proposes to review main kind of dysalbuminemia usually encountered in clinical biology laboratories.

Recurrent retinal vein occlusion in a patient with increased plasma levels of histidine-rich glycoprotein.

PURPOSE: To report an association between retinal vein occlusion and increased plasma levels of histidine-rich glycoprotein. DESIGN: Observational case report. METHODS: A 56-year-old woman presented with sudden and painless decrease of visual acuity of her right eye. Indirect ophthalmoscopy revealed retinal vein occlusion. She had experienced central retinal vein occlusion in this eye 6 years earlier. RESULTS: The patient's medical history was negative for cardiovascular risk factors. Further investigation into possible causes revealed increased values for histidine-rich glycoprotein. CONCLUSIONS: When ordering laboratory tests in patients with retinal vein occlusion to rule out coagulation disorders, increased plasma levels of histidine-rich glycoprotein should be considered in the differential diagnosis. Selective screening may be helpful in identifying retinal vein occlusion patients with thrombophilic defects, especially in young individuals with recurrent retinal vein occlusion in the absence of recognized cardiovascular risk factors.

Laboratory diagnosis of von Willebrand disorder (vWD) and monitoring of DDAVP therapy: efficacy of the PFA-100 and vWF:CBA as combined diagnostic strategies.

We have coevaluated a combination of test processes for diagnosing von Willebrand disease (vWD) and monitoring deamino-delta-D-arginine vasopressin (DDAVP) therapy. Using normal controls (n = 23), closure time (CT) ranges measured by PFA-100(R) were (mean +/- 2SD): (i) collagen/ADP cartridge (C/ADP): 67-127 s (ii) collagen/epinephrine (C/Epi): 94-162 s. From a panel of 125 patients undergoing evaluation for clinical haemostatic defects, 29/30 samples from patients with vWD [17/18 type 1, 1/1 type 3, 3/3 type 2A, 7/7 type 2B and 1/1 pseudo-vWD] gave prolonged CTs using C/Epi. The C/ADP was less sensitive, being normal in 7/18 of the type 1 vWD individuals, with higher sensitivity to more severe vWD. Individuals with haemophilia (six factor VIII-deficient, one factor XI-deficient) gave normal CTs, while those with clinical thrombocytopenia (n=13) gave normal or prolonged CTs, somewhat dependent on platelet count. The PFA-100 was also evaluated as a part of the laboratory monitoring procedure in patients with either vWD or haemophilia undergoing a DDAVP trial as a therapeutic management process. For vWD, correction of an initially prolonged CT by DDAVP, accompanied by normalization of von Willebrand factor (vWF) measurable by von Willebrand factor antigen, vWF collagen binding activity and vWF ristocetin cofactor assays (vWF:Ag, vWF:CBA and vWF:RCof), was achieved in type 1 vWD (n=5). In an individual with type 2A vWD, DDAVP normalized vWF:Ag and vWF:RCof, but had no apparent effect on the baseline maximally prolonged CT. In an individual with type 2B vWD, factor VIII/vWF concentrate also normalized vWF:Ag and vWF:RCof, but similarly had no apparent effect on the baseline maximally prolonged CT. vWF:CBA did not normalize for either of these individuals, potentially suggesting that normalization of vWF:CBA might be required for normalization of CT. This concept is supported by correlation analysis undertaken between CT and various vWF parameters. Among these, vWF:CBA held the strongest relationship in our data set, which showed an inverse progressive rise in CT for falling vWF:CBA. Based on these results, we would conclude that the PFA-100 is highly sensitive to the presence of vWD, and may thus provide a valuable screening test for vWD. Furthermore, the combined utility of the PFA-100 and vWF:CBA as markers of DDAVP responsiveness may prove to be simple, quick but powerful, predictors for its clinical efficacy.

Differential diagnosis of gammopathies by capillary electrophoresis and immunosubtraction: analysis of serum samples problematic by agarose gel electrophoresis.

The capabilities of capillary electrophoresis (CE) for serum protein electrophoresis and immunotyping have been demonstrated. CE-based systems specifically designed for serum protein electrophoresis and immunotyping via immunosubtraction (IS) are now available and are being evaluated for efficiency, specificity and sensitivity by several groups. The use of CE for serum protein electrophoresis and immunotyping (IS) in the clinical laboratory compares well with agarose gel electrophoresis (AGE) and immunofixation (IF) for the detection and characterization of monoclonal proteins. In addition to routine use, this technology is useful for a subset of serum samples that are difficult to interpret with conventional technology. In this study, sera abnormalities difficult to detect/interpret by AGE-IF are subdivided into four categories: (i) patients with polyclonal increases in immunoglobulin, (ii) point of application artifacts, (iii) abnormalities in the beta region, and (iv) patients with free light chains. CE is superior to AGE for evaluating samples characterized by the above abnormalities. Sera containing monoclonal proteins within a polyclonal increase are easier to detect by CE as well as being easier to type by IS than by IF. Point-of-application artifacts, periodically observed with AGE, do not exist on CE since the point of detection is remote from the point of application. Enhanced resolution in the beta region allows for increased detection of monoclonal proteins migrating in this region. Some free light chains are undetected by CE as a result of no apparent abnormalities on the CE serum protein profile and, thus, still require IF for detection. CE detects more serum electrophoretic abnormalities than AGE in this clinically important group of patients with Bence Jones proteinemia.

Angioimmunoblastic lymphadenopathy with dysproteinemia--lack of a prognostic value of clear cell morphology.

It has been suggested that angioimmunoblastic lymphadenopathy with dysproteinemia (AILD) is closely related to peripheral T cell lymphoma (PTCL). However, the clinical course of AILD-like PTCL is notoriously unpredictable. A minor portion of patients enjoyed prolonged remission with steroid-only treatments (indolent AILD) while most others died rapidly despite the use of intensive chemotherapy (aggressive AILD). Recently, it has been suggested that histological features such as the presence or absence of clear cells and convoluted cells are of high prognostic value. The validity of this observation was addressed in this study. Eighteen patients who presented between 1977 and 1994 at the National Taiwan University Hospital were retrospectively studied. There were 11 men and 7 women, with a median age of 47 years. Twelve patients had received various regimens of systemic chemotherapy, and the other 3 patients had been treated with steroids alone. Eight patients had indolent AILD and 6 aggressive AILD. The follow-up period in 4 patients was too short to be analyzed. The histopathology of these cases was divided, according to the criteria of Aozasa et al., into group I (neither cells), 4 patients; group II (only convoluted cells), 1 patient, and group III (clear cells with or without convoluted cells), 13 patients. Contrary to others, our data revealed that group III patients were doing better than group I patients. Univariate analysis of other pertinent clinical features, including sex, age, lymphadenopathy, B symptoms, hepatosplenomegaly, hypergammaglobulinemia, elevated serum lactate dehydrogenase, and treatment regimens, revealed none of them to be prognostically relevant. However, patients who had achieved complete remission by steroids or other systemic chemotherapy had a significantly better prognosis than those who had not. Together, these preliminary data suggested that (1) the presence or absence of clear cells and convoluted cells failed to predict the clinical behavior, and (2) induction of complete remission by steroids or other chemotherapeutic agents is an important prognostic index.

Activated protein C resistance in homozygous sickle cell disease.

The activated protein C resistance (APC-R) ratios in 50 patients with steady state homozygous sickle cell (SS) disease and 59 healthy AA controls was measured. There was a significant reduction in median APC-R ratio in sickle cell disease compared to controls. This reduction in APC-R ratio was not explained by (1) the presence of the factor V Leiden, found in only one of 165 patients with SS disease including those tested for APC-R, or (2) the presence of lupus anticoagulants. However, the raised levels of factor VIIIC in SS patients in this study may be contributing to increased resistance to APC, which in turn may contribute to the vaso-occlusive complications of SS disease.

Activated protein C resistance in homozygous sickle cell disease

The activated protein C resistance (APC-R) ratios in 50 patients with steady state homozygous sickle cell (SS) disease and 59 healthy AA controls was measured. There was a significant reduction in median APC-R ratio in sickle cell disease compared to controls. This reduction in APC-R ratio was not explained by (1) the presence of the factor V Leiden, found in only one of 165 patients with SS disease including those tested for APC-R, or (2) the presence of lupus anticoagulants. However, the raised levels of factor VIIIC in SS patients in this study may be contributing to the increased resistance to APC, which in turn may contribute to the vaso-occlusive complication of SS disease.(AU)