Mean Corpuscular Volume Levels Research Articles

Toxic Synergism Between Aflatoxin and T-2 Toxin in Broiler Chickens

The individual and combined effects of aflatoxin and T-2 toxin were studied in male broiler chicks (Hubbard × Hubbard). The experimental design was a 2 × 2 factorial design with dietary treatments of 0 and 2.5 μg/g aflatoxin and 0 and 4.0 μg/g T-2 toxin. The broilers were obtained at 1 day of age and housed in electrically heated batteries with feed and water available ad libitum until they reached 3 wk of age. Aflatoxicosis in this study was characterized by a significant (P<.05) reduction in body weight, changes in red blood cell counts and serum levels of protein, albumin, glucose, cholesterol, and calcium, and magnesium, activity of the serum enzymes lactic dehydrogenase and alkaline phosphatase, and a significant (P<.05) increase in relative weights of the liver, kidney, spleen, pancreas, proventriculus, and heart. Dietary T-2 toxin alone caused oral lesions, a significant (P<05) decrease in serum protein, albumin, potassium, and magnesium levels, and a significant (P<.05) decrease in the activity of the serum enzymes lactic dehydrogenase and alkaline phosphatase. In the combination treatment of aflatoxin and T-2 toxin, significant (P<.05) interactive effects were seen through a decrease in body weights, increase in the relative weights of the kidney, gizzard, and heart, and decrease in mean corpuscular volume and serum levels of potassium. These data indicate that aflatoxin and T-2 toxin can interact to produce synergistic toxicity. This synergism is a threat to poultry production due to the prevalence of these mycotoxins and severity of the interactive toxicity of these mycotoxins.

Regional Variations in Sickle Cell Anemia in Saudi Arabia

ABSTRACT We examined mean corpuscular volume (MCV), fetal hemoglobin (HbF) levels, and severity of clinical disease in 81 patients with sickle cell anemia from various regions of Saudi Arabia. We f...

Hematologic and blood chemical characteristics of feral horses from three management areas.

Blood was collected from 486 feral horses of mixed sex and age classes captured from three wild horse management areas in Nevada and Oregon from December 1985 to February 1986. Males were significantly outnumbered by females in the Flanigan area, but both sexes were represented in approximately equal numbers in the Wassuk and Beaty's Butte areas. Hematology and chemistry values averaged 16.4 +/- 0.11, 46.3 +/- 0.28, 9.9 +/- 0.07, 6.9 +/- 0.10, 47.1 +/- 0.24, 16.6 +/- 0.09, 35.2 +/- 0.09, 10.4 +/- 0.14 and 23.4 +/- 0.25 for hemoglobin (HGB), hematocrit (HCT), red blood cells (RBC), white blood cells (WBC), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), cortisol (F) and serum urea nitrogen (SUN), respectively. Statistically significant differences in HGB, HCT, RBC, WBC, MCV and MCH levels occurred with respect to age (P less than or equal to 0.001). Serum F levels were lower in immature animals than in either subadult or adults in all areas. Flanigan horses appeared in the poorest condition and had the lowest HGB, HCT and RBC counts while the values for Wassuk horses were significantly higher (P less than or equal to 0.001). Serum F levels were lowest in the Flanigan horses. A significantly lower (P less than or equal to 0.001) proportion of adult mares had progesterone levels consistent with pregnancy in the Flanigan horses versus those from the other two areas. These data are consistent with a subjective evaluation of the condition of the horses.

Effects of Glucose-6-Phosphate Dehydrogenase Deficiency Upon Sickle Cell Anemia

We studied the interactions of the A- variety of glucose-6-phosphate dehydrogenase (G6PD) deficiency and sickle cell anemia (HbSS) to see if G6PD deficiency influenced laboratory and clinical features of HbSS. A total of 801 male patients over age 2 had G6PD electrophoresis on cellulose acetate membranes. Assays of both G6PD activity and hexokinase activity were then done on all samples that had an electrophoretic pattern other than the normal wild type (GdB). The collection of clinical data used a standardized protocol. Using cluster analyses we classified 10.4% males to be G6PD deficient, while 18.4% had the functionally normal GdA+ enzyme. The prevalence of G6PD deficiency did not change significantly when age was stratified by decade, suggesting little survival advantage or disadvantage of the combination of G6PD deficiency and HbSS. Compared to patients who were not G6PD deficient, there were no significant differences in the hemoglobin concentration, mean corpuscular volume, reticulocyte count, bilirubin, or SGOT level in patients with HbSS who had G6PD deficiency. The incidence of painful episodes, sepsis, or acute anemic episodes was similar in both groups. Our results are consistent with recent studies of smaller numbers of patients that have found little influence of G6PD deficiency upon HbSS. Specifically, we found no evidence that G6PD enhanced the severity of hemolysis or increased the incidence of acute anemic episodes or sepsis in HbSS.

Effects of glucose-6-phosphate dehydrogenase deficiency upon sickle cell anemia

We studied the interactions of the A- variety of glucose-6-phosphate dehydrogenase (G6PD) deficiency and sickle cell anemia (HbSS) to see if G6PD deficiency influenced laboratory and clinical features of HbSS. A total of 801 male patients over age 2 had G6PD electrophoresis on cellulose acetate membranes. Assays of both G6PD activity and hexokinase activity were then done on all samples that had an electrophoretic pattern other than the normal wild type (GdB). The collection of clinical data used a standardized protocol. Using cluster analyses we classified 10.4% males to be G6PD deficient, while 18.4% had the functionally normal GdA+ enzyme. The prevalence of G6PD deficiency did not change significantly when age was stratified by decade, suggesting little survival advantage or disadvantage of the combination of G6PD deficiency and HbSS. Compared to patients who were not G6PD deficient, there were no significant differences in the hemoglobin concentration, mean corpuscular volume, reticulocyte count, bilirubin, or SGOT level in patients with HbSS who had G6PD deficiency. The incidence of painful episodes, sepsis, or acute anemic episodes was similar in both groups. Our results are consistent with recent studies of smaller numbers of patients that have found little influence of G6PD deficiency upon HbSS. Specifically, we found no evidence that G6PD enhanced the severity of hemolysis or increased the incidence of acute anemic episodes or sepsis in HbSS.

Treatment of Rheumatoid Arthritis with Desferrioxamine

Desferrioxamine was used to treat six patients who had rheumatoid arthritis refractory to conventional treatment, on the basis that levels of intra-articular iron would be reduced and inflammation lessened. After a period of initial intensive treatment which was limited by side effects, five patients continued on once-weekly maintenance doses. Two patients had temporary improvement in their symptoms, but relapsed in spite of continuing treatment. The remaining three patients completed six months of treatment with no improvement in their rheumatoid disease. There were no significant changes in rheumatological parameters, immunological markers of disease activity nor radiological evidence of improvement. Treatment did lead to significant falls in haemoglobin concentration (p less than 0.01), mean corpuscular volume (p less than 0.05) and serum ferritin levels (p less than 0.02). Therefore, in spite of a reduction in iron available for haem synthesis and a fall in tissue storage iron the rheumatoid inflammatory process persisted.

Selenium status of malnourished hospitalized patients.

We evaluated selenium (Se) status of 44 hospitalized patients with protein-energy malnutrition. The patients were assigned to "normal" or "low" Se groups-1 and 2, respectively-based on whether the plasma Se level exceeded or was below the value of the mean-2SD of healthy Georgians'. Plasma and erythrocyte Se levels correlated significantly (r = .52, P less than .01). Erythrocyte glutathione peroxidase activity was highly correlated with plasma Se (r = .68) in group 2; there was no significant correlation between these parameters in group 1. In group 2 the mean plasma prealbumin level was significantly lower, and the mean corpuscular volume and serum glutamic oxaloacetic transaminase level were significantly higher compared to group 1. Other nutritional parameters did not correlate with Se status. Concomitant deficiencies of other nutrients were common in both patient groups. Se levels may relate to protein status, and abnormal hematologic and hepatic parameters may reflect low Se status and/or protein-energy malnutrition. Low Se status is common in malnourished patients from a low Se area, and Se supplementation should be included in their nutritional-repletion regimens.

Tea drinking and microcytic anemia in infants

To evaluate the effect of tea drinking on the occurrence of microcytic anemia in infants, we studied 122 healthy infants who underwent routine blood counts at the age of 6-12 months. An overall high frequency of anemia (Hb less than 11 gm/dl-48.4%), microcytosis (MCV less than 70 Mm3-21.3%) and microcytic anemia (19%) was found in the whole group. The percentage of tea drinking infants with microcytic anemia (32.6%) was significantly higher than that of the non-tea drinkers (3.5%). The daily amount of tea drinking was 50-750 ml (median 250 ml). The tea drinkers had significantly lower mean levels of hemoglobin than that of the non-tea drinkers (10.5 +/- 1.2 gm/dl vs 11.2 +/- 0.8 gm/dl, respectively) and significantly lower mean levels of mean corpuscular volume than that of the non-tea drinkers (71.5 +/- 7.1 micron 3 vs 76.1 +/- 4.6 micron 3). There were no significant differences between the two groups in their sex distribution and in the duration of breast feeding. The two groups differed with regard to their ages and social class but a multivariate analysis had excluded the possible confounding effect of these differences on the hematological results. Based on our finding we do not recommend giving tea to infants whose main source of iron is from milk, grains, vegetables or medicinal sources.

Evaluation of a prenatal screening procedure for beta-thalassaemia carriers in a Chinese population based on the mean corpuscular volume (MCV).

Haemoglobin A2 (HbA2) levels were determined on 25 beta-thalassaemia carriers by the microcolumn method and were found to range from 4.5-7.2 per cent (mean 5.2 +/- 0.82 S.D.). The haemoglobin level (Hb), mean corpuscular volume (MCV), plasma ferritin and HbA2 levels were measured on a further 299 consecutive Chinese pregnant women at a gestation of less than 24 weeks. 18 patients (6 per cent) had HbA2 level greater than 4.5 per cent and were diagnosed to be beta-thalassaemic carriers. It was observed that all these patients had a MCV below 75 fl. If this level is selected in a screening procedure based on measurement of MCV alone all beta-thalassaemia carriers could be detected and 11 per cent of the population screened would require HbA2 estimation. At a lower cut-off level of 70 fl, 8 per cent of the population screened would require HbA2 measurement (a decrease of 27 per cent) but the detection rate will be lowered considerably (83 per cent). The high false positive rate at all cut-off levels of MCV was largely due to the prevalence of iron deficiency anaemia in the population. Estimation of plasma ferritin level in patients with low MCV will reduce this false positive rate, but there will be a considerable delay in diagnosis in patients with concomitant iron deficiency and beta-thalassaemia. The presence of iron deficiency in beta-thalassaemia carriers did not reduce their HbA2 level below the diagnostic range in this study.(ABSTRACT TRUNCATED AT 250 WORDS)

The interaction of alpha-thalassemia and homozygous sickle-cell disease.

Patients with homozygous sickle-cell disease may be homozygous for alpha-thalassemia 2 (alpha-/alpha-), may be heterozygous for alpha-thalassemia 2 (alpha-/alpha alpha), or may have a normal alpha-globin-gene complement (alpha alpha/alpha alpha). We compared the clinical and hematologic features of 44 patients who had sickle-cell disease and homozygous alpha-thalassemia 2 with those of controls with the two hematologic conditions. The patients with homozygous alpha-thalassemia 2 had significantly higher red-cell counts and levels of hemoglobin and hemoglobin A2, as well as significantly lower hemoglobin F, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, mean corpuscular volume, reticulocyte counts, irreversibly-sickled cell counts, and serum total bilirubin levels, than those with a normal alpha-globin-gene complement. Heterozygotes (alpha-/alpha alpha) had intermediate values. In the group with homozygous alpha-thalassemia 2, fewer patients had episodes of acute chest syndrome and chronic leg ulceration and more patients had splenomegaly, as compared with patients in other two subgroups. These data confirm previous suggestions that alpha-thalassemia inhibits in vivo sickling in homozygous sickle-cell disease and may be an important genetic determinant of its hematologic severity.

The effect of supplemental ascorbic acid on serum vitamin B12 levels in myelomeningocele patients

Serum levels of ascorbic acid and vitamin B12 were analyzed in 40 myelomeningocele children to study the effect of supplemental ascorbic acid on serum vitamin B12 levels. The experimental group was composed of 20 children receiving ascorbic acid for urinary acidification: 10 received an average of 1.8 g daily, 10 received an average of 1.5 g daily (the amount depending on the requirement needs for urinary acidification) half of each group received ascorbic acid for less than 3 yr (an average of 2.1 yr) and half received ascorbic acid for more than 3 yr (an average of 4.3 yr). The control group consisted of 20 myelomeningocele children not receiving supplemental ascorbic acid. Both groups were matched for age, sex, race, and physical activity. Dietary levels of ascorbic acid and B12 were calculated to rule out their influence on serum levels. Results showed that the experimental group with supplemental ascorbic acid produced significantly higher ascorbic acid values than the control group. The serum B12 levels of the experimental group were not significantly different than those of the control groups and these children showed neither a deficient serum levels of B12, anemia, nor elevated mean corpuscular volume. Hemoglobin levels were slightly higher for the experimental group. Dietary calculations of B12 and ascorbic acid were not significantly greater than the Recommended Daily Allowance ruling out any influence of diet on serum levels. No evidence of vitamin B12 deficiency developed in 20 myelomeningocele children receiving daily mean doses of 1.65 g of supplemental ascorbic acid. In view of our findings, it is highly improbable that megadoses of supplemental ascorbic acid would induce vitamin B12 deficiency in man.

The clinical significance of macrocytosis.

The cause of macrocytosis (mean corpuscular volume (MCV) greater than or equal to 105 fl) was investigated over a period of 16 months in the 70 known cases of +/- 4000 patients seen by the Department of Internal Medicine. By means of simple laboratory investigations the cause of elevated MCV was found in more than 90% of the cases. We found vitamin B12 or folic acid deficiency in 27 patients, alcohol abuse in 18, chronic persistent hepatitis in 2, hematological (pre-) malignancy in 9, hemolysis in 4, hypothyroidism in 2, and a drug effect in one patient. In 6 cases the elevated MCV could not be explained. Macrocytosis, a frequent finding that is not related to the hemoglobin concentration, is an indicator of serious pathology. The MCV level can be used to differentiate between the diagnostic categories. Only 21 patients (30%) had megaloblastic erythropoiesis that was difficult to recognize in the peripheral blood. Among the findings at routine laboratory investigations an elevated MCV may be the only indicator of vitamin deficiency, preleukemia or alcoholism.

Erythrocyte and Leukocyte Parameters in Newborn Lambs

SUMMARY Erythrocyte and leukocyte values were estimated in samples of blood from 32 lambs varying in age from 142 to 180 days post conception. Total erythrocyte count, packed cell volume and haemoglobin levels all decreased during the period 142 to 160 days, but rose afterwards. The mean corpuscular volume and mean corpuscular haemoglobin levels decreased in a similar manner but did not increase subsequently. Volume distribution curves exhibited a progressive fall in the standard deviation, accompanied by an increase in the coefficient of variation and degree of skewness. A small but significant number of reticulocytes was present at 150 to 160 days post conception. The total nucleated cell population showed no significant variation during the period under review. The lymphocyte/neutrophil ratio rose significantly from 160 to 180 days post conception. A transient increase in the numbers of neutrophil precursors at 150 to 160 days was not accompanied by a left shift in segmented cells.