Pyknocytosis is a hematologic state characterized by the presence of pyknocytes in the blood. Pyknocytes are red blood cells that appear distorted, irregular and small with abnormal projections and would typically be identified by a medical scientist and verified by a pathologist on a peripheral blood smear.
Infantile pyknocytosis is the most commonly associated condition, and is a rare pediatric hematological condition. [1] It is a potential cause of neonatal hemolytic anemia. Infantile pyknocytosis typically presents with neonatal jaundice and severe anemia, often requiring blood transfusions. The associated hemolytic anemia is often transient with peak incidence at 3–4 weeks, with spontaneous and complete resolution by four to six months of life. [2] An etiology for this condition has not been established but some evidence, including the presence of dehydrated red cells on peripheral blood smear that seem to have undergone oxidative stress, points to causes that include deficiency of antioxidants such as vitamin E or the presence of an oxidative factor. The diagnosis of infantile pyknocytosis is essentially based on the peripheral blood smear, with additional diagnostic investigations to rule out similarly presenting conditions such as glucose-6-phosphate dehydrogenase deficiency and pyruvate kinase deficiency. Both of these conditions can also result in pyknocytes observable on the blood smear. Treatment involves phototherapy if blood bilirubin levels are greater than normal for the age of the infant, and blood transfusion if hemoglobin is found to be unacceptably low or decreasing based on clinical judgement of laboratory values.[ citation needed ]
Hemolysis or haemolysis, also known by several other names, is the rupturing (lysis) of red blood cells (erythrocytes) and the release of their contents (cytoplasm) into surrounding fluid. Hemolysis may occur in vivo or in vitro.
Anemia is a decrease in the total amount of red blood cells (RBCs) or hemoglobin in the blood, or a lowered ability of the blood to carry oxygen. When anemia comes on slowly, the symptoms are often vague and may include feeling tired, weakness, shortness of breath, and a poor ability to exercise. When the anemia comes on quickly, symptoms may include confusion, feeling like one is going to pass out, loss of consciousness, and increased thirst. Anemia must be significant before a person becomes noticeably pale. Additional symptoms may occur depending on the underlying cause. For people who require surgery, pre-operative anemia can increase the risk of requiring a blood transfusion following surgery.
Glucose-6-phosphate dehydrogenase deficiency (G6PDD) is an inborn error of metabolism that predisposes to red blood cell breakdown. Most of the time, those who are affected have no symptoms. Following a specific trigger, symptoms such as yellowish skin, dark urine, shortness of breath, and feeling tired may develop. Complications can include anemia and newborn jaundice. Some people never have symptoms.
Hereditary spherocytosis is an abnormality of red blood cells, or erythrocytes. A chronic disease with a long term health condition with no cure. The disorder is caused by mutations in genes relating to membrane proteins that allow for the erythrocytes to change shape. The abnormal erythrocytes are sphere-shaped (spherocytosis) rather than the normal biconcave disk shaped. Dysfunctional membrane proteins interfere with the cell's ability to be flexible to travel from the arteries to the smaller capillaries. This difference in shape also makes the red blood cells more prone to rupture. Cells with these dysfunctional proteins are degraded in the spleen. This shortage of erythrocytes results in hemolytic anemia.
Hemolytic anemia is a form of anemia due to hemolysis, the abnormal breakdown of red blood cells (RBCs), either in the blood vessels or elsewhere in the human body (extravascular). This most commonly occurs within the spleen, but also can occur in the reticuloendothelial system or mechanically. Hemolytic anemia accounts for 5% of all existing anemias. It has numerous possible consequences, ranging from general symptoms to life-threatening systemic effects. The general classification of hemolytic anemia is either intrinsic or extrinsic. Treatment depends on the type and cause of the hemolytic anemia.
Plummer–Vinson syndrome is a rare disease characterized by difficulty swallowing, iron-deficiency anemia, glossitis, cheilosis and esophageal webs. Treatment with iron supplementation and mechanical widening of the esophagus generally provides an excellent outcome.
Hemolytic disease of the newborn, also known as hemolytic disease of the fetus and newborn, HDN, HDFN, or erythroblastosis foetalis, is an alloimmune condition that develops in a fetus at or around birth, when the IgG molecules produced by the mother pass through the placenta. Among these antibodies are some which attack antigens on the red blood cells in the fetal circulation, breaking down and destroying the cells. The fetus can develop reticulocytosis and anemia. The intensity of this fetal disease ranges from mild to very severe, and fetal death from heart failure can occur. When the disease is moderate or severe, many erythroblasts are present in the fetal blood, earning these forms of the disease the name erythroblastosis fetalis.
Megaloblastic anemia is a type of macrocytic anemia that results from inhibition of DNA synthesis during red blood cell production. When DNA synthesis is impaired, the cell cycle cannot progress from the G2 growth stage to the mitosis (M) stage. This leads to continuing cell growth without division, which presents as macrocytosis. Megaloblastic anemia has a rather slow onset, especially when compared to that of other anemias. The defect in red cell DNA synthesis is most often due to hypovitaminosis, specifically vitamin B12 deficiency or folate deficiency. Loss of micronutrients may also be a cause.
A schistocyte or schizocyte is a fragmented part of a red blood cell. Schistocytes are typically irregularly shaped, jagged, and have two pointed ends.
Acanthocyte, in biology and medicine, refers to an abnormal form of red blood cell that has a spiked cell membrane, due to thorny projections. A similar term is spur cells. Often they may be confused with echinocytes or schistocytes.
Sideroblastic anemia, or sideroachrestic anemia, is a form of anemia in which the bone marrow produces ringed sideroblasts rather than healthy red blood cells (erythrocytes). In sideroblastic anemia, the body has iron available but cannot incorporate it into hemoglobin, which red blood cells need in order to transport oxygen efficiently. The disorder may be caused either by a genetic disorder or indirectly as part of myelodysplastic syndrome, which can develop into hematological malignancies.
Autoimmune hemolytic anemia (AIHA) occurs when antibodies directed against the person's own red blood cells (RBCs) cause them to burst (lyse), leading to an insufficient number of oxygen-carrying red blood cells in the circulation. The lifetime of the RBCs is reduced from the normal 100–120 days to just a few days in serious cases. The intracellular components of the RBCs are released into the circulating blood and into tissues, leading to some of the characteristic symptoms of this condition. The antibodies are usually directed against high-incidence antigens, therefore they also commonly act on allogenic RBCs. AIHA is a relatively rare condition, affecting one to three people per 100,000 per year. Autoimmune hemolysis might be a precursor of later onset systemic lupus erythematosus.
Paroxysmal cold hemoglobinuria (PCH) is an autoimmune hemolytic anemia featured by complement-mediated intravascular hemolysis after cold exposure. It can present as an acute non-recurrent postinfectious event in children, or chronic relapsing episodes in adults with hematological malignancies or tertiary syphilis. Described by Julius Donath (1870–1950) and Karl Landsteiner (1868–1943) in 1904, PCH is one of the first clinical entities recognized as an autoimmune disorder.
In ABO hemolytic disease of the newborn maternal IgG antibodies with specificity for the ABO blood group system pass through the placenta to the fetal circulation where they can cause hemolysis of fetal red blood cells which can lead to fetal anemia and HDN. In contrast to Rh disease, about half of the cases of ABO HDN occur in a firstborn baby and ABO HDN does not become more severe after further pregnancies.
Cold agglutinin disease (CAD) is a rare autoimmune disease characterized by the presence of high concentrations of circulating cold sensitive antibodies, usually IgM and autoantibodies that are also active at temperatures below 30 °C (86 °F), directed against red blood cells, causing them to agglutinate and undergo lysis. It is a form of autoimmune hemolytic anemia, specifically one in which antibodies bind red blood cells only at low body temperatures, typically 28–31 °C.
Hemolytic disease of the newborn (anti-Kell1) is the second most common cause of severe hemolytic disease of the newborn (HDN) after Rh disease. Anti-Kell1 is becoming relatively more important as prevention of Rh disease is also becoming more effective.
The term macrocytic is from Greek words meaning "large cell". A macrocytic class of anemia is an anemia in which the red blood cells (erythrocytes) are larger than their normal volume. The normal erythrocyte volume in humans is about 80 to 100 femtoliters. In metric terms the size is given in equivalent cubic micrometers. The condition of having erythrocytes which are too large, is called macrocytosis. In contrast, in microcytic anemia, the erythrocytes are smaller than normal.
Normocytic anemia is a type of anemia and is a common issue that occurs for men and women typically over 85 years old. Its prevalence increases with age, reaching 44 percent in men older than 85 years. The most common type of normocytic anemia is anemia of chronic disease.
A degmacyte or bite cell is an abnormally shaped mature red blood cell with one or more semicircular portions removed from the cell margin, known as "bites". These "bites" result from the mechanical removal of denatured hemoglobin during splenic filtration as red cells attempt to migrate through endothelial slits from splenic cords into the splenic sinuses. Bite cells are known to be a result from processes of oxidative hemolysis, such as Glucose-6-phosphate dehydrogenase deficiency, in which uncontrolled oxidative stress causes hemoglobin to denature and form Heinz bodies. Bite cells can contain more than one "bite." The "bites" in degmacytes are smaller than the missing red blood cell fragments seen in schistocytes.
Anemia is a condition in which your blood has a lower-than-normal amount of red blood cells or hemoglobin. Anemia in pregnancy is a decrease in the total red blood cells (RBCs) or hemoglobin in the blood during pregnancy or in the period following pregnancy. It involves a reduction in the oxygen carrying capacity of the blood. Anemia is an extremely common condition in pregnancy and postpartum world-wide, conferring a number of health risks to mother and child. Maternal signs and symptoms are usually non-specific, but can include: fatigue, pallor, dyspnea, palpitations, and dizziness. There are numerous well-known maternal consequences of anemia including: maternal cardiovascular strain, reduced physical and mental performance, reduced peripartum blood reserves, increased risk for peripartum blood product transfusion, and increased risk for maternal mortality.