Lower Mean Corpuscular Hemoglobin Research Articles

Diurnal changes in the haemoglobin level, red blood cell number and mean corpuscular haemoglobin in foals during the first 13 weeks of life and in their lactating mothers

1. 1. In six foals and their mothers (of Standard breed) diurnal changes in the haemoglobin level, red blood cell number and mean corpuscular haemoglobin during the first 13 weeks of foal life were studied. 2. 2. Studies begun when a foal reached 7 days of age and were repeated every two weeks till 13 weeks of foal life. Blood was taken every 6 hr in foals and every 4 hr in mares. 3. 3. No diurnal rhythmicity in parameters studied either in foals or in mares was found. 4. 4. Decrease of haemoglobin level in lactating mares (14.0–12.5 g/100 ml) without changes in red blood cell number were observed. Mean corpuscular haemoglobin changed distinctly from one study day to another. 5. 5. In foals were stated: significantly higher haemoglobin level and erythrocyte number and lower mean corpuscular haemoglobin than in mares.

The Hemogram, Serum Biochemistry, and Electrolyte Profile of Aged Rhesus Monkeys (Macaca mulatto)

The hemogram, serum biochemicals, and electrolytes of aged (15- to 28-year-old) rhesus monkeys were compared with values for younger adults (4-14 years old) maintained under identical conditions. Aged males had lower mean corpuscular volume, serum iron and magnesium, and higher percentages of eosinophils, globulins, and triglycerides than adult males. Aged females had lower mean corpuscular hemoglobin, total leukocyte count, percentage of neutrophils, alkaline phosphatase and magnesium, and higher percentages of lymphocytes and eosinophils, globulins, and uric acid than adult females.

Haematology and Blood Chemistry of the Free-Living Platypus, Ornithorhynchus anatinus (Shaw) (Monotremata: Ornithorhynchidae)

Blood was collected under ether anaesthesia from a bill sinus in 45 platypuses, Ornithorhynchus anatinus, caught in southeastern New South Wales. Sexual dimorphisms in haematological and blood chemical values were not found, but there were age-related changes. Juvenile animals had greater erythrocyte counts, lower mean corpuscular volumes, higher potassium, calcium, inorganic phosphate, alkaline phosphatase, cholesterol and albumin, but lower sodium, bicarbonate, urea and protein levels than adults. Reasons for these differences are discussed. Compared to other mammals, the platypus had high haematocrit, erythrocyte count and haemoglobin levels, together with low mean corpuscular volume and high mean corpuscular haemoglobin concentration, which may indicate adaptation to hypoxia. Reticulocytes were not observed. All animals had a small parasite in fewer than 1% of their red cells. Total leukocyte counts were also higher than in other mammals, the mean for adults being 42.84 X 10*9.l-�. The ratio of neutrophils to lymphocytes was approximately 0 5. Metamyelocyte neutrophils were present in low numbers in 14 healthy platypuses. Levels of serum potassium and creatinine were lower, while those of urea, alkaline phosphatase, aspartateaminotransferase and alanineaminotransferase were higher than those usually reported for healthy mammals.

Diagnosis of iron deficiency anemia in a rural population of children. Relative usefulness of serum ferritin, red cell protoporphyrin, red cell indices, and transferrin saturation determinations

The diagnostic usefulness in iron deficiency anemia of serum ferritin, red cell protoporphyrin (Epp), mean corpuscular volume, mean corpuscular hemoglobin (MCH), and transferrin saturation measurements has been studied in a population of 294 children aged 1 to 6 yr. Of the children studied 19% had hemoglobin below 11 g/dl. Iron deficiency, diagnosed by at least two abnormal independent laboratory parameters, was the cause of anemia in all except two cases. The Pearson correlation coefficient for hemoglobin was highest with MCH, followed in decreasing order of magnitude by MCV, Epp, transferrin saturation, and finally by ferritin. Sensitivity and specificity were highest for MCH and lowest for ferritin. Of anemic, iron deficient individuals 97 to 100% could be identified by low MCH, 88 to 100% by transferrin saturation, 66 to 83% by ferritin, and 61 to 74% by Epp. In contrast, only 0 to 6% of normal, nonanemic individuals had low MCH, 0 to 4% had high Epp, but 21 to 39% had low transferrin saturation and 25 to 39% had low ferritin. Although reduced serum ferritin in anemic individuals is good evidence of iron deficiency, a significant proportion of anemic iron-deficient patients is missed by this procedure rendering it less useful than other, less expensive laboratory methods.

Hb Bart's and its significance in the South African Negro.

The haematological indices of cord bloods from 430 South African Negro babies were determined by electronic cell counting and their haemoglobin (Hb) patterns examined by alkaline cellulose acetate electrophoresis. A fast-moving, anodal band, identified as Hb Bart's, was found in 7 (1,6%) of the specimens, this being the lowest incidence of the variant yet found in an indigenous African population. The levels of Hb Bart's ranged from 1.3 to 5.5% of the haemoglobin. These findings were confirmed by alkaline-starch gel electrophoresis and at the same time absence of the slow-moving haemoglobin, Hb Constant Spring was established. Subsequent follow-up of 4 of the infants at 4 months of postnatal life showed that the abnormal component had disappeared. The babies with Hb Bart's had a marked microcytosis and low mean corpuscular haemoglobin levels whilst their parents showed no haematological or electrophoretic signs of alpha-thalassaemia. The significance of these findings is discussed in the light of previously reported studies on various Negro groups.

Glucose phosphate isomerase deficiency with congenital nonspherocytic hemolytic anemia: a new variant (type Nordhorn). I. Clinical and genetic studies.

Extract: A new variant of glucose phosphate isomerase (GPI) deficiency (type Nordhorn) associated with congenital nonspherocytic hemolytic anemia is described. The propositus, an 18-month-old boy of German origin, has suffered since birth from a severe to moderate macrocytic anemia, which is characterized by low mean corpuscular hemoglobin concentration (28%), high reticulocytosis (45—60%), normal osmotic fragility, type I autohemolysis, and short erythrocyte life-span (51Cr t1/2 = 2 days). With the exception of GPI, the activities of most erythrocyte enzymes are increased. GPI activity is decreased to 22% of the normal. The father and mother exhibit GPI activities between 36% and 47% of normal. No difference is demonstrable between the enzyme of the propositus and normal subjects concerning Michaelis-Menten constant for fructose 6-phosphate, pH optimum, and thermal optimum. The stability of the enzyme is decreased in the propositus and in all affected maternal relatives. The enzyme of the paternal relatives is stable. On starch-gel electrophoresis the enzyme of the father is normal (three bands). In the hemolysate of the mother a fourth cathodally migrating band is demonstrable in addition to the three normal bands. The propositus exhibits only one band with a cathodal mobility of 132% of the main band of normal subjects. It is suggested that the propositus is double heterozygous for two abnormal alleles. The heterozygote mother contributes an allele which produces a thermolabile enzyme of decreased activity and abnormal electrophoretic mobility, whereas the father contributes an allele without enzymatic activity.The enzyme defect is also manifest in the leukocytes of the propositus (39% of normal activity). The thermolability is evident in the leukolysates of the propositus and in those of his mother.When erythrocyte glucose consumption and lactate formation are compared with nonenzymopenic, reticulocyte-rich blood, which has no metabolic defect, the rate of glycolysis is markedly impaired in the propositus. Glucose 6-phosphate, the substrate before the defect, accumulates fourfold and probably inhibits hexokinase, and consequently glycolysis. Compared with erythrocyte populations of similar mean cell age, the concentrations of ATP and 2,3-diphosphoglycerate are decreased. After separation of young from old cells the defect becomes more evident in the older population. Premature inactivation of the enzyme during maturation is suggested.Speculation: Many so-called “homozygous states” of inherited enzyme defect: could be double heterozygous as well. Double heterozygosity may partially explain the clinical heterogeneity of the “homozygous” manifestation, and the lack of correlation between residual enzyme activity and clinical expression in many inborn errors of metabolism. In double heterozygotes with glucose phosphate isomerase deficiency, a premature inactivation of the enzyme during maturation of the erythrocytes may be the reason for metabolic impairment of the celIs, followed by premature hemolysis.

Cerebrovascular accidents in infants and children with cyanotic congenital heart disease

Cerebrovascular accidents unrelated to surgery, brain abscess or subacute bacterial endocarditis remain a serious complication in patients with cyanotic congenital heart disease. To determine the risk factors for cerebrovascular accidents, we reviewed our experience in 29 consecutive cases and in a control group of 220 cases. The overall incidence of cerebrovascular accidents in patients with cyanotic congenital heart disease was 1.6 percent. Of 30 cerebrovascular accidents, 21 occurred in infants and children between 5 months and 4 years of age and 9 in older patients. Ninety percent of the accidents occurred in patients with tetralogy of Fallot and dextrotransposition of the great arteries. Hemiplegia was precipitated by acute febrile illness in six patients, cardiac catheterization in two and hyperpneic spells in two. Seven patients recovered completely, and 20 had residual hemiplegia. A seizure disorder developed in five patients and mental retardation in four. Three patients died (mortality rate 10 percent). Cerebrovascular accidents in patients less than 4 years of age were associated with anemia (low mean corpuscular hemoglobin concentration) and hypoxemia. By contrast, cerebrovascular accidents in older patients were associated with polycythemia and hypoxemia. The data suggest that spontaneous cerebrovascular accidents may be prevented in infants and young children with cyanotic congenital heart disease by medical treatment of anemia and surgical relief of the hypoxemia. Since the cardiovascular malformations in 90 percent of our patients who had a cerebrovascular accident are amenable to surgical correction, an aggressive surgical approach with early correction of the malformations may significantly reduce the incidence of this complication.

Re-assessment of the reliability of the haematocrit.

Summary. Significant quantities of plasma are trapped between the centrifuged red cells in the microhaematocrit. This produces a falsely high haematocrit and mean corpuscular volume, and a falsely low mean corpuscular haemoglobin concentration. Trapped plasma accounts for approximately 3% of the normal red‐cell column. Slightly higher values are found in macrocytic anaemias, but values as high as 5–6% may be found in the hypochromic anaemias, and even over 20% in sickled samples of blood.It is suggested that automatic blood counters of the Coulter S type be set to record a true haematocrit without trapped plasma. This value is 1 1/2% less than the microhaematocrit value with normal blood. Absolute values in normal subjects under these conditions are reported.