Ultrastructure of bone marrow in patients with visceral leishmaniasis.

Ultrastructural studies were performed on bone marrow aspirates from three patients with visceral leishmaniasis. The patients were moderately anaemic but showed a suboptimal increase in the absolute reticulocyte count. Serum and red cell folate concentrations and serum vitamin B12 concentrations were normal in all three cases, and serum ferritin concentrations were normal or increased. The bone marrows were hypercellular and showed erythroid hyperplasia; a high proportion of the erythroblasts showed dyserythropoietic changes. Amastigote forms of Leishmania donovani were found within bone marrow macrophages and within occasional neutrophil and eosinophil granulocytes. Electron microscopy showed the presence of many abnormal cells, which probably represented immature erythroblasts with giant lysosomes. These cells were often large, usually contained immature nuclei with relatively little condensed chromatin, had 1-20 electron dense cytoplasmic granules with an average diameter of 0.5 micron, and regularly displayed substantial rhopheocytotic activity. A few abnormal cells and intermediate and late erythroblasts appeared to have been phagocytosed by macrophages. The data indicate that dyserythropoiesis and ineffective erythropoiesis have a role in the pathogenesis of the anaemia of at least some cases of kala-azar.     

Use of plasma ferritin concentration to diagnose iron deficiency in elderly patients.

AIMS--To determine a concentration of ferritin below which the possibility of iron deficiency should be considered in elderly patients. METHODS--Consecutive new referrals to a geriatric unit (n = 472) were studied prospectively. Full blood count, ferritin, serum vitamin B12 and red cell folate were measured for all patients. A blood film was assessed independently by three haematologists for features of iron deficiency. For those with ferritin of 12-45 ng/ml, bone marrow aspirates were performed and examined for the presence of stainable iron. When possible, a trial of oral iron was given to those with ferritin of < or = 45 ng/ml and response was determined by re-measurement of full blood count and ferritin after a minimum of three weeks of treatment. RESULTS--Bone marrow examination was performed in 32 patients with ferritin of 12-45 ng/ml, of whom 27 (84%) had absent stainable iron, suggesting that most elderly patients with ferritin in this range have iron deficiency. Compared with those with ferritin of 100-299 ng/ml, in whom iron stores were presumed to be normal, patients with ferritin of 12-45 ng/ml had a significantly lower mean haemoglobin and mean red blood cell volume. Furthermore, patients with ferritin up to 75 ng/ml had a significantly higher mean red cell distribution width, and were more likely to have an iron deficient blood film. CONCLUSION--Iron deficient erythropoiesis can occur in elderly patients with ferritin up to 75 ng/ml. This is much higher than the lower limit of the "normal" range usually quoted for younger subjects; this difference should be taken into account when ferritin concentrations are interpreted in elderly patients.     

Red cell folate concentrations in psychiatric patients

Red cell folate and vitamin B12 estimations were performed on 243 successively admitted in-patients at a District General Hospital Psychiatric Unit and 42 out-patients (29 attending a lithium clinic). Patients were classified into five diagnostic groups. The mean ages of the manic and schizophrenic patients were lower than of the depressed or euthymic patients but age was not correlated with red cell folate or serum B12 levels in any group. There were 89 (31%) patients with red cell folate below 200 ng/ml and 35 (12%) with concentrations below 150 ng/ml. Significantly more of these low-folate patients were in-patients than out-patients. The mean red cell folate in the depressed patients was significantly lower than in the euthymic, manic and schizophrenic groups. Alcoholics had a similar mean red cell folate to depressed patients which was not quite significantly lower than the other groups. The mean serum B12 level in the alcoholics was, however, significantly raised. There were no significant differences in red cell folate or serum B12 between lithium-treated and untreated euthymic patients. The highest proportions of values below 200 ng/ml and 150 ng/ml were found in depressed and alcoholic patients. Endogenous depressives had the highest percentage of values below 150 ng/ml (folate-deficient) of all psychiatric groups and alcoholic patients. The significance of these findings is discussed.     

Assessment of the value of a competitive protein binding radioassay of folic acid in the detection of folic acid deficiency

The diagnostic value of the Becton Dickinson Radioassay Kit (125I) for the the assay of red cell folate has been investigated. The assay was acceptable with regards to precision but was non-linear with changing packed cell volume. Sensitivity of the assay was satisfactory, with 24 of 25 folate deficient patients giving red cell folate values which fell below the reference range. Specificity of the assay in the detection of folate deficiency was less satisfactory. As with microbiological assays, a considerable proportion of vitamin B12 deficient patients had low red cell folate values. In addition, low concentrations were found in 12% of patients who were unlikely to be deficient in either vitamin B12 or folic acid.     

Platelet monoamine oxidase activity in megaloblastic anaemia.

Platelet monoamine oxidase activity has been measured in 17 patients with megaloblastic anaemia due to either vitamin B12 or folate deficiency, and in 20 healthy subjects. There was a highly significant increase in patients compared with controls. In two patients, platelet activity decreased following successful treatment. A significant correlation between platelet activity and the severity of bone marrow megaloblastic change, assessed by the deoxyuridine suppression test and bone marrow morphology, was also observed. If the change in activity also occurs in the nervous system, this may contribute to the mental disturbance associated with vitamin B12 or folate deficiency.     

Investigations of bone marrow dyscrasia in a poodle with macrocytosis

A poodle-type dog with bone marrow dyscrasia and macrocytosis was investigated by clinicopathological, cytological and ultrastructural means. Peripheral blood analysis revealed macrocytosis and the presence of nucleated erythroid cells, some with nuclear/cytoplasmic asynchrony. Tendencies towards neutropenia and granulocytic hypersegmentation were observed. Bone marrow examination revealed low normal myeloid to erythroid ratio, the presence of megaloblasts and some giant metamyelocytes. In addition, there were abnormal mitoses, binuclearity and multinuclearity, incomplete nuclear membranes and nuclear clefts, intracytoplasmic parallel-sided membranes and apparent degenerate erythroid cells. Blood biochemical tests indicated normal to high concentrations of serum vitamin B12, serum folate and red cell folate. Transcobalamin I/IIIB12-binding capacity was similar to values for normal dogs, but transcobalamin II-binding capacity appeared high. It was concluded that the condition had similarities to both congenital dyserythropoietic disorders and true megaloblastic conditions, but until further investigations are reported it might be wise to refer to it as "bone marrow dyscrasia" in poodles.     

Blastic transformation of essential thrombocythemia. A case report

A case of blastic transformation of essential thrombocythemia (ET) is reported. A 69-year-old male was first admitted to hospital because of fever in February, 1982. He was diagnosed as having ET because of marked thrombocytosis (205.5 x 10(10)/1), absence of erythrocytosis, absence of splenomegaly, normal karyotype and no increment of blasts in the bone marrow, and normal levels of neutrophil alkaline phosphatase, vitamin B12 and folate. He was treated with busulfan, and subsequently his platelet count was well controlled for about five years. At the second admission, blasts were present in the peripheral blood, and later accounted for 49% of the total leukocyte count. Histological examination of a bone biopsy specimen showed homogeneous proliferation of blastic cells and slight reticulin fibrosis. At autopsy, the degree of bone marrow fibrosis had increased. This was considered to be a very rare case of ET with blastic transformation in the terminal phase.     

Diagnostic value of the serum folate assay

The diagnostic value of the serum folate assay has been assessed in 90 patients, each of whom had a macrocytic anaemia and a low serum vitamin B(12) level. Twenty-nine (32%) patients were found to have anaemia due primarily to folate deficiency. The cause of the low serum vitamin B(12) levels is uncertain in the 22 (25%) patients with normal or borderline vitamin B(12) absorption. The effect of folic acid therapy was studied in four of these patients, and in each case the serum vitamin B(12) rose slowly to a normal level.The serum folate was low in only four (7.5%) of the 54 patients with pernicious anaemia, and the levels rose to normal on treatment with vitamin B(12) alone. A high serum folate occurred in eight (15%) pernicious anaemia patients. A normal serum folate indicated the diagnosis of pernicious anaemia or megaloblastic anaemia following partial gastrectomy. However, a normal serum folate and a very low vitamin B(12) level was found in two patients with idiopathic steatorrhoea.It is concluded that the serum folate assay is a valuable routine test in patients who have a macrocytic anaemia and low serum vitamin B(12). A low folate level makes the diagnosis of pernicious anaemia unlikely and is a strong indication for full investigation of small intestinal function.     

Early detection of folic acid deficiency in elderly patients.

Folic acid deficiency is very common in elderly patients who have a mean red cell volume greater than 94 fl. Eighteen out of 40 elderly patients with red cell macrocytosis who initially had normal red cell folate and serum B12 levels subsequently developed folic acid deficiency.     

Elevated plasma homocysteine levels in centenarians are not associated with cognitive impairment

BACKGROUND: Previous reports have shown elevated plasma total homocysteine (tHcy) levels in elderly person with impaired cognition. OBJECTIVE: To study the association between cognitive status and plasma tHcy levels in centenarians. DESIGN: Cross-sectional survey. SETTING: Centenarians living in two northern Italian provinces. PARTICIPANTS: Thirteen cognitively normal centenarians, ten cognitively impaired not-demented centenarians, and 34 demented centenarians with a clinical diagnosis of Alzheimer's disease (AD). MEASUREMENTS: Blood levels of homocysteine's biological determinants vitamin B12, folate, and vitamin B6. RESULTS: Elevated plasma tHcy levels (>17 micromol/l) were common in the general population (77% of normal centenarians, 100% of cognitively impaired not-demented centenarians, 82% of AD centenarians). Demented centenarians had the lowest folate serum levels. Low or borderline vitamin B12 serum levels (<221 pmol/l) and low vitamin B6 plasma levels (<11.7 nmol/l) were found in 33 and 66% of all centenarians independently of cognitive status. Among demented centenarians only plasma tHcy correlated inversely with both serum vitamin B12 and folate. No significant difference was found for plasma tHcy levels among the three diagnostic groups, even after adjusting for B vitamin levels. CONCLUSIONS: Hyperhomocysteinemia is very common among centenarians, probably due to vitamin deficiencies, but does not seem to be associated with cognitive impairment.     

Blastic Transformation of Essential Thrombocythemia

A case of blastic transformation of essential thrombocythemia (ET) is reported. A 69 year old male was first admitted to hospital because of fever in February, 1982. He was diagnosed as having ET because of marked thrombocytosis (205.5 ± 10¹⁰/1), absence of erythrocytosis, absence of splenomegaly, normal karyotype and no increment of blasts in the bone marrow, and normal levels of neutrophil alkaline phosphatase, vitamin B₁₂ and folate. He was treated with busulfan, and subsequently his platelet count was well controlled for about five years. At the second admission, blasts were present in the peripheral blood, and later accounted for 49% of the total leukocyte count. Histological examination of a bone biopsy specimen showed homogeneous proliferation of blastic cells and slight reticulin fibrosis. At autopsy, the degree of bone marrow fibrosis had increased. This was considered to be a very rare case of ET with blastic transformation in the terminal phase. Acta Pathol Jpn 39: 670-676, 1989.     

Do antidepressants cause folic acid depletion? A pilot study

Chronic administration of tricyclic antidepressants is common; folic acid depletion is a potential consequence adversely affecting the mental state. In a pilot study prior to research in the community, serum and red cell folate and serum vitamin B ₁₂ levels were measured in the following elderly psychiatric inpatients: 14 controls (patients not receiving any drugs with known antifolate activity), 11 receiving tricyclic antidepressants, 13 receiving antipsychotics (phenothiazines) and four receiving an anticonvulsant (carbamazepine). Patients on prolonged treatment with carbamazepine or phenothiazine drugs had lower concentrations of folate in serum and erythrocytes compared with controls; the decrease was statistically significant for the effect of phenothiazines on serum folate levels. Tricyclic antidepressants, which are in widespread use in the community, did not cause folate depletion during the first two years of treatment.     

Investigation of statistical decision rules for sequential hematologic laboratory tests

A statistical data processing program for identifying patients who are likely to have abnormalities on various hematologic laboratory tests is described. The prediction of abnormal levels of serum vitamin B12, serum folate, transferrin saturation, and reticulocyte counts is based on a statistical analysis of the patient's age, sex, and routine blood cell measurements. The program was developed using data from normal-value studies and data from patients who had these laboratory abnormalities. The sensitivity and specificity of the program were evaluated in a controlled prospective study of about 5,000 ambulatory adult patients. The program's predictions also were compared with the laboratory tests requested by the patients' attending physicians. The program was most sensitive for predicting low serum vitamin B12 (74%) and low transferrin saturation (78%). In the prospective evaluation, the predictive values varied from 11% for predicting low serum folate to 65% for predicting low transferrin saturation.     

Elevated plasma homocysteine levels in centenarians are not associated with cognitive impairment

Background: Previous reports have shown elevated plasma total homocysteine (tHcy) levels in elderly person with impaired cognition. Objective: To study the association between cognitive status and plasma tHcy levels in centenarians. Design: Cross-sectional survey. Setting: Centenarians living in two northern Italian provinces. Participants: Thirteen cognitively normal centenarians, ten cognitively impaired not-demented centenarians, and 34 demented centenarians with a clinical diagnosis of Alzheimer's disease (AD). Measurements: Blood levels of homocysteine's biological determinants vitamin B12, folate, and vitamin B6. Results. Elevated plasma tHcy levels (>17 μmol/l) were common in the general population (77% of normal centenarians, 100% of cognitively impaired not-demented centenarians, 82% of AD centenarians). Demented centenarians had the lowest folate serum levels. Low or borderline vitamin B12 serum levels (<221 pmol/l) and low vitamin B6 plasma levels (<11.7 nmol/l) were found in 33 and 66% of all centenarians independently of cognitive status. Among demented centenarians only plasma tHcy correlated inversely with both serum vitamin B12 and folate. No significant difference was found for plasma tHcy levels among the three diagnostic groups, even after adjusting for B vitamin levels. Conclusions: Hyperhomocysteinemia is very common among centenarians, probably due to vitamin deficiencies, but does not seem to be associated with cognitive impairment.     

Experiences with dual protein bound aqueous vitamin B12 absorption test in subjects with low serum vitamin B12 concentrations.

A dual isotope vitamin B12 absorption test in which vitamin B12 is given both in aqueous solution and bound to protein (chicken serum), was evaluated in 26 controls and 68 patients with subnormal serum vitamin B12 concentrations (19 with pernicious anaemia, 13 with iron deficiency, seven after partial gastrectomy, seven with malabsorptive states, five with folate deficiency, four with chronic alcoholism and 13 in whom no cause was apparent). In control patients protein bound absorption decreased with age; isotope excretion was 1.0% or over in those aged under 60 and 0.5% or over in those aged 60 and above. Malabsorption of protein bound vitamin B12 with normal aqueous absorption occurred in five patients with iron deficiency, three with alcoholism, two after partial gastrectomy, two with folate deficiency and in one with a malabsorptive state. In alcoholics abstinence produced an improvement in protein bound absorption. All patients in the group for whom no cause could be found for the subnormal serum vitamin B12 concentration had normal aqueous absorption but four had malabsorption of protein bound vitamin. Although the dual isotope test gave reproducible results and was consistent with the standard Schilling test some anomalies were detected; nine patients had reduced aqueous absorption with normal protein bound absorption. Despite this the dual test may prove useful in determining the importance of a subnormal vitamin B12 concentration where the cause is not clinically apparent. Further development is needed before it can be considered for routine use.     

Combination of biomarkers to predict mortality in elderly patients with myocardial infarction

OBJECTIVE: The elderly subjects affected by Acute Myocardial Infarction (AMI) have the highest risk of mortality. Our study was designed to improve the capability of mortality risk stratification in elderly AMI patients through the concurrent evaluations of different biomarkers, including genetic markers. METHODS AND RESULTS: One-year follow-up study was performed in 250 elderly AMI patients. The combination of high total Homocysteine (tHcy), low folate and vitamin B12 plasma levels (18.0+/-9.0 micromol/l; 4.4+/-1.2 ng/ml; 404.2+/-287.5 pg/ml, respectively) and elevated CRP plasma levels (> or =6 mg/dl) identify the highest-risk pathway of heart mortality (RR=4.20, IC 95% 1.62-10.89, P<0.002) with respect to the combination of low total tHcy, high folate and vitamin B12 plasma levels (12.4+/-5.2 micromol/l; 8.9+/-2.5 ng/ml; 546.9+/-379.8 pg/ml, respectively) and low CRP plasma levels (<6 mg/dl). CONCLUSION: In elderly AMI patients the concomitant elevation of CRP and tHcy, associated with folate and vitamin B12 low levels, could be considered a significant predictive heart mortality risk factor.     

Folate and vitamin B12 status of adolescent girls in northern Nigeria

The diets of populations in many developing countries are low in folate and vitamin B12 and a deficiency of either of these vitamins results in increased risk for cardiovascular disease and neural tube defects. The rates of neural tube defects in Nigeria are among the highest reported worldwide. Since many girls marry at an early age in northern Nigeria, we therefore determined the folate and vitamin B12 status of adolescent girls between 12 and 16 years of age in Maiduguri, Nigeria. The mean serum folate concentration for subjects was 15.3 +/- 5.2 nmol/L. Whereas only four subjects (2.4%) had serum folate concentrations lower than 6.8 nmol/L, a level indicative of negative folate balance, 9% of the subjects had serum vitamin B12 concentrations at or below 134 pmol/L, the lower limit of the reference range for their age group. Serum homocysteine was measured in 56 of the 162 subjects and the mean level was 15.9 +/- 5.0 mumol/L. The majority of subjects had serum homocysteine concentrations above the upper limit of the reference range for their age group. We conclude that the adolescent girls we studied were at greater risk for vitamin B12 deficiency than folate deficiency. This conclusion is consistent with the fact that their diet included few foods that contained vitamin B12.     

Red cell N5-methyltetrahydrofolate concentrations and C677T methylenetetrahydrofolate reductase genotype in patients with stroke

AIMS: To investigate the relation between total red cell folate, red cell N(5)-methyltetrahydrofolate (N(5)MTHF) concentrations, and N(5)N(10)-methylenetetrahydrofolate reductase (MTHFR) genotypes in stroke. METHODS: The study comprised 120 consecutive patients presenting to hospital with acute stroke. Multivitamin supplement use was recorded. Serum and red cell folate were measured by microbiological assays using Lactobacillus casei and Enterococcus faecalis, and by the DPC-BioMediq Immulite 2000 analyser. Total plasma homocysteine (tHcy), serum cobalamin, and serum vitamin B(6) were measured and the C677T MTHFR genotype determined. RESULTS: There were no significant differences in blood tHcy or vitamin concentrations according to MTHFR genotype in the overall patient cohort. However, when patients taking vitamins were excluded, total red cell folate and red cell N(5)MTHF were significantly lower in patients with the TT genotype compared with CT or CC genotypes. In the overall cohort, irrespective of genotype, red cell folate was significantly lower when assayed microbiologically than with the Immulite assay. This discrepancy remained after exclusion of patients taking vitamins. CONCLUSION: Total red cell folate and red cell N(5)MTHF are significantly lower in stroke patients with the TT compared with the CT and TT MTHFR genotypes, particularly those not taking vitamin supplements. Microbiological assays that measure biologically active folates provide substantially lower estimates of folate than the Immulite assay. Because folate is a key determinant of blood homocysteine values, these findings may impact on the interpretation of the strength and independence of the association between raised blood concentrations of homocysteine and atherothrombosis risk reported in most epidemiological studies.     

Haemoglobin A2 levels in vitamin B12 and folate deficiency.

Haemoglobin A2 levels were measured in 50 patients with vitamin B12 deficiency, 50 patients with folate deficiency, and six patients with combined deficiencies of these vitamins. All were normal except for three patients with vitamin B12 deficiency, who had a slightly elevated Hb A2 level; this fell to normal after vitamin B12 therapy. It is concluded that haemoglobin A2 levels are usually normal in vitamin B12 or folate deficiency. However, raised levels of haemoglobin A2 may be found, but these are not as high as is found in beta thalassaemia trait and should not cause difficutly in diagnosis.     

Vitamin B12 deficiency neurological syndromes: a clinical,MRI and electrodiagnostic study

BACKGROUND: Vegetarianism is an important cause of vitamin B12 deficiency, especially in countries like India. We managed 17 patients with neurological syndrome due to vitamin B12 deficiency in a tertiary care referral teaching hospital which caters to relatively affluent population. AIM: To evaluate neurophysiological and MRI changes in patients presenting with vitamin B12 deficiency neurological syndrome and interpret these is the light of reported autopsy findings. SETTING: Tertiary care referral teaching hospital. METHODS: Patients with vitamin B12 deficiency neurological syndrome diagnosed by low serum vitamin B12 and/or megaloblastic bone marrow were subjected to clinical evaluation and spinal MRI. The neurophysiological tests included nerve conduction studies, tibial somatosensory evoked potential (SEP), motor evoked potential (MEP) and visual evoked potential (VEP) studies. The recovery was defined on the basis of 6 months Barthel Index score into complete, partial or poor. RESULTS: There were 17 patients with vitamin B12 deficiency neurological syndrome, 3 were females and 12 lactovegetarian. The clinical syndrome was that of myelopathy in 8, myeloneuropathy in 5, dementia myelopathy in 3 and neuropathy in 1 patient. All the patients had impaired joint position and vibration sensation in the lower limbs and 4 had in upper limbs as well. Lower limbs were spastic in 13 and upper limbs in 2 patients. Spinal MRI revealed T2 hyperintensity in cervicodorsal region in 6 and cord atrophy in 3 patients. Sural nerve conduction was abnormal in 8 and peroneal conduction in 5 patients. In one patient all sensory nerve conductions were unrecordable but motor conductions were normal. Tibial SEP was abnormal in 12 out of 15 and lower limb MEP in 8 out of 12 patients. P100 latency of VEP was prolonged in 7 out of 13 patients. Right to left asymmetry was present in tibial SEP in 4 and VEP in 2 patients. At 6 months followup 2 patients improved completely, 7 partially and 3 had poor recovery. Clinical recovery correlated with MEP but not with SEP or MRI changes. CONCLUSION: The evoked potential and MRI changes in vitamin B12 deficiency neurological syndrome are consistent with focal demyelination of white matter in spinal cord and optic nerve. Myelopathic presentation is commoner and SEP is more frequently abnormal. The outcome at 6 months correlated with MEP changes.