OBJECTIVES Paroxysmal nocturnal hemoglobinemia (PNH) is a rare but serious condition characterized by complement-mediated red blood cell (RBC) hemolysis and episodic thrombotic attack. It results from decay accelerating factor (CD55), and protectin (CD59), becoming attached to RBC and other cell surfaces. Absence of these protective proteins leaves such cells vulnerable to self attack at the C3...

By WILLIArsI H. CROSBY AND NAOMI R. BENJAMIN I HE RED BLOOD CELLS of patients with paroxysmal nocturnal hemoglobinuria ( PNH ) possess an apparently unique susceptibility to the hemolytic activity of certain naturally occurring plasma factors. Hemolysis occurs readily in vitro and the reaction is intensified when the incubating mixture has been made slightly acid. This phenomenon is the basis o...

Paroxysmal nocturnal hemoglobinuria (PNH) is a hematologic disorder characterized by an acquired somatic mutation in the phosphatidylinositol glycan class A gene which leads to a higher risk for increased venous and arterial thrombosis. Current treatment for PNH includes eculizumab. Pregnant patients who have PNH have higher risk for thrombosis and hemorrhage with both pregnancy and their under...

paroxysmal nocturnal hemoglobinuria (pnh) is a rare hematologic disorder that manifests with hemolytic anemia, thrombosis, and peripheral blood cytopenias.acute abdominal pain is one of the pnh clinical manifestations due to venous thrombosis of intra-abdominal sites including hepatic, portal, mesenteric, and splenic veins.eculizumaband allogeneic bone marrow transplantation (bmt) arethe only w...

Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired clonal hematologic disorder that affects both sexes equally. The biochemical defect in PNH resides in the incomplete enzymatic assembly of glycosylphosphatidylinositol (GPI) anchors used for surface protein attachment. In all PNH patients tested to date, the biosynthetic defect occurs at the addition of N-acetyl-glucosamine to the phospha...

OBJECTIVE To examine the utility of repetitive nerve stimulation (RNS) in the evaluation of peripheral nerve hyperexcitability (PNH). BACKGROUND PNH describes a group of disorders characterized by muscle cramps, twitching and stiffness. When severe, PNH may be characterized by the presence of continuous muscle fiber activity on routine needle electromyography (EMG). In milder forms of the dis...

The mechanism of bone marrow failure (BMF) in paroxysmal nocturnal hemoglobinuria (PNH) is not yet known. Because in PNH the biosynthesis of the glycolipid molecule glycosylphosphatidylinositol (GPI) is disrupted in hematopoietic stem and progenitor cells by a somatic mutation in the PIG-A gene, BMF might result from an autoimmune attack, whereby T cells target GPI in normal cells, whereas PIG-...

OBJECTIVE We studied a case series of peripheral nerve hyperexcitability (PNH) aiming to describe clinical characteristics, immunologic and cancer associations, antibodies against neuronal antigens (voltage-gated potassium channel antibodies [VGKC-Abs] and other), and muscle biopsy findings. METHODS Patients presenting with clinical and electrophysiologic signs of PNH were selected. We studie...

Paroxysmal nocturnal hemoglobinuria (PNH) is characterized by the triad of intravascular hemolysis, venous thrombosis, and cytopenia. Treatment of PNH is generally supportive. Bone marrow transplantation is the only curative therapy for PNH, but is associated with significant morbidity and mortality. Herein, we present a patient with PNH that received eculizumab, a humanized monoclonal antibody...

Lipids extracted with chloroform-methanol from red blood cell membranes of 7 PNH and 13 control subjects were used for the preparation of liposomes, which were then examined with the reactive lysis test. PNH liposomes lysed to a higher extent than control liposomes as indicated by the higher dilution of the limiting complement reagent that was necessary to lyse 50% of the PNH liposomes. A simil...