Strengths and weaknesses of methods for identifying monoclonal free light chains of Ig: examples from two cases with renal disease

BACKGROUND

Serum free light chain (FLC) analysis with ratio and urine immunofixation electrophoresis (IFE) are both available for routine use in helping to detect plasma cell dyscrasia and related diseases.

CASES

Case reports showing one serum positive for serum FLC but that showed a hook effect and overestimated the amount of monoclonal FLC while urine IFE was negative for Bence Jones protein, and a second serum that showed elevated FLC κ and λ but a normal κ/λ ratio, while urine IFE was positive for Bence Jones protein.

CONCLUSIONS

These two techniques complement one another. Neither of the techniques is truly quantitative, and both exhibit methodological defects.

Lamivudine-associated macrocytosis in HIV-infected patients

Macrocytosis has been increasingly observed in HIV-infected population and is an early indicator of bone marrow toxicity. A retrospective study was conducted among these patients in a HIV clinic to assess risk factors of macrocytosis. We found that lamivudine was strongly associated with macrocytosis (OR = 24.6 [2.9–3223.0], P = 0.001). This association may be due to lamivudine's effect on erythrocyte synthesis.

Lenalidomide treatment induced the normalization of marker protein levels in blood plasma of patients with 5q-myelodysplastic syndrome

A specific type of myelodysplastic syndrome (MDS) is associated with isolated deletion on the long arm of chromosome 5, i.e., 5q-syndrome (del(5q)). The treatment approaches for MDS del(5q) include the immunomodulating drug lenalidomide (LEN). Thirteen MDS del(5q) patients were included in this study. We found elevated activities of lactate dehydrogenase (LDH) and matrix metalloproteinase 9 (MMP-9) in the blood plasma of MDS del(5q) patients as compared with healthy controls. This was stabilized to control values after LEN treatment. Similar behavior we registered also for the thioredoxin and calnexin contents in BP. Peripheral blood mononuclear cells (PBMC) from patients with MDS del(5q) prior to and after treatment with LEN did not exhibit any detectable amount of P-glycoprotein (P-gp) gene transcript. However, we detected a measurable amount of multidrug resistance associated protein 1 (MRP1) mRNA in PBMCs from three patients prior to LEN treatment and in one patient during LEN treatment but it was not present prior to treatment. These data indicated on usefulness of applied protein markers estimation for monitoring of MDS del(5q) patient treatment effectiveness by LEN. Expression of MRP1 seems to be independent on LEN treatment and reflects probably the molecular variability in the ethiopathogenesis of MDS del(5q).

A retrospective study of 1,098 blood samples with anemia from adult cats: frequency, classification, and association with serum creatinine concentration

BACKGROUND

Frequency and classification of anemia in terms of regeneration status and erythrocyte indices are not well described in cats.

OBJECTIVE

To determine frequency and regenerative status of anemia in samples from adult cats, to assess the sensitivity and specificity of macrocytosis and hypochromasia for detecting regenerative anemia (RA), and to evaluate the association of anemia with increased serum creatinine concentration (SC).

STUDY POPULATION

Laboratory records from 30,503 blood samples from cats (2003-2011).

METHODS

Clinicopathologic data reviewed retrospectively. Anemia defined as hematocrit (Ht) ≤27%, red blood cell count (RBC) ≤5.5 × 10(6)/μL and hemoglobin (Hb) ≤9.0 g/dL. RA defined by manual absolute reticulocyte count >50 × 10(3)/μL. Macrocytosis was defined as mean corpuscular volume (MCV) >55 fL and hypochromasia as mean corpuscular hemoglobin concentration (MCHC) <31 g/dL. Cutoff for increased serum creatinine concentration was 1.6 mg/dL.

RESULTS

Overall, 1,098 of 30,503 blood samples (3.6%) from cats fulfilled criteria for anemia, 633 of 1,098 (57.7%) classified as nonregenerative (NRA) and 465 of 1,098 (42.3%) as regenerative. RBC, Ht, and Hb were significantly lower in the RA compared to NRA group (P < .05). Sensitivity and specificity of the combined high MCV and low MCHC to detect samples with RA were 19.5 and 90.7%. SC was increased in 572 of the 1,098 anemic samples (52.1%) and in 11,121 of 29,405 of nonanemic samples (37.8%).

CONCLUSIONS AND CLINICAL IMPORTANCE

Majority of anemic samples were classified as NRA. Anemia was more severe in cats with RA. Erythrocyte indices were not sensitive indicators of RA.

Two cases of acute erythroid leukemia presenting with marked macrocytic anemia, reticulocytosis and hemolysis

Case 1. The laboratory findings of a hematological analysis of a 53-year-old woman with palpitations and dyspnea revealed the following: red blood cell (RBC) count: 9.4×10(5)/μL with 60.0‰ reticulocytes; Hb: 3.7 g/dL; mean corpuscular volume (MCV): 124.5 fL; white blood cell (WBC) count: 2,800/μL with 10.0% myeloblasts. Case 2. Similarly, a 42-year-old man with dizziness had a RBC count of 1.63×10(6)/μL with 24.0% reticulocytes, an Hb level of 6.0 g/dL, an MCV of 120.2 fL and a WBC count of 3,100/μL with 4.0% myeloblasts. Bone marrow aspirates in both patients confirmed a diagnosis of acute erythroid leukemia (AEL), which can present as marked macrocytic anemia with an MCV in excess of 120 fL and hemolysis.

[Reticulocytes in the diagnosis of anaemia]

Reticulocytes are immature erythrocytes; the number of reticulocytes in the peripheral blood reflects erythropoietic activity. Two cases are described to illustrate the use of the reticulocyte count in the diagnostic workup of anaemia. The first patient was a 62-year-old woman presenting with fatigue. Laboratory evaluation showed severe macrocytic anaemia, thrombocytopaenia and the presence of schistocytes. A low reticulocyte count suggested decreased erythropoiesis underlying the anaemia; this led to the diagnosis of vitamin B12 deficiency. The second patient, a 52-year-old woman, also presented with fatigue and macrocytic anaemia. A high reticulocyte count indicated increased erythrocyte degradation, and the patient was eventually diagnosed with autoimmune haemolytic anaemia. The role of reticulocytes in the differential diagnostic workup of anaemia was explored on the basis of these case descriptions. The test methodology, analytical performance, reference values and pitfalls were discussed, as well as the reticulocyte indices and their use in monitoring therapy.

Molecular Characterization and Diagnosis of Hb Crete [β129(H7)Ala→Pro]

We report the molecular characterization of Hb Crete [beta129(H7)Ala-->Pro] in a female subject from the Greek island of Crete. DNA sequence analysis revealed a 1368 GCC-->CCC base substitution in exon 3 of the beta-globin gene, leading to the Ala-->Pro amino acid change at codon 129. Both the proband and her mother, who were found to be heterozygotes for Hb Crete, presented with mild microcytic anemia and normal Hb A2 levels and iron metabolism indices. This is the first description of an heterozygous Hb Crete case, and also the first report on the molecular basis of Hb Crete. Moreover, the proposed NlaVI restriction enzyme-based detection of Hb Crete at the DNA level is a fast and accurate approach, useful for molecular diagnostics.

Impact of drug-eluting versus bare-metal stents on mortality in patients with anemia

OBJECTIVES

Our aim was to assess the incidence of all-cause mortality in patients with anemia undergoing percutaneous coronary intervention (PCI) receiving drug-eluting stents (DES) or bare-metal stents (BMS).

BACKGROUND

Anemia has been associated with poor clinical outcomes in patients undergoing PCI. However, it is unknown whether stent selection (DES or BMS) has a differential outcome in this high-risk group.

METHODS

Anemia was defined as a hematocrit below 36% for female subjects and below 40% for male subjects as defined by the World Health Organization. All patients undergoing PCI with DES or BMS alone from March 2003 to June 2007 were included. The primary end point was all-cause mortality. Anemia was further characterized using mean corpuscular volume as microcytic, normocytic, or macrocytic.

RESULTS

A total 11,181 patients underwent PCI over a 4.5-year interval; of these, 2,172 met our inclusion criteria. There were a total of 429 deaths. The majority of patients had normocytic anemia (n = 1,931). Of the 3 anemia subtypes, macrocytic anemia (DES 26%, BMS 44%) had the highest mortality followed by normocytic (DES 17%, BMS 25%) and microcytic (DES 13%, BMS 18%) anemia, respectively. All-cause mortality was significantly lower with DES in unadjusted and multivariable adjusted Cox proportional models (adjusted hazard ratio: 0.66, 95% confidence interval: 0.54 to 0.82; p < 0.001).

CONCLUSIONS

In an adjusted analysis, the use of DES as compared with the use of BMS was associated with decreased mortality in patients with anemia. Additionally, among anemia subtypes, macrocytic anemia had the highest mortality.

Evaluation of macrocytosis

Macrocytosis, generally defined as a mean corpuscular volume greater than 100 fL, is frequently encountered when a complete blood count is performed. The most common etiologies are alcoholism, vitamin B12 and folate deficiencies, and medications. History and physical examination, vitamin B12 level, reticulocyte count, and a peripheral smear are helpful in delineating the underlying cause of macrocytosis. When the peripheral smear indicates megaloblastic anemia (demonstrated by macro-ovalocytes and hyper-segmented neutrophils), vitamin B12 or folate deficiency is the most likely cause. When the peripheral smear is non-megaloblastic, the reticulocyte count helps differentiate between drug or alcohol toxicity and hemolysis or hemorrhage. Of other possible etiologies, hypothyroidism, liver disease, and primary bone marrow dysplasias (including myelodysplasia and myeloproliferative disorders) are some of the more common causes.

Hematological and gill histopathological parameters of three tropical fish species from a polluted lagoon on the west coast of Mauritius

Gill histopathology and hematological primary indices, including blood delta-aminolevulinic acid dehydratase (deltaALA-D) activity and nucleocytoplasmic ratio of erythrocytes, were assessed in three tropical marine fish species, Scarus ghobban, Epinephelus merra, and Siganus sutor, from the presumably contaminated lagoon of Bain des Dames, Mauritius. Concurrently, the nonpolluted region of Blue Bay/Pt d'Esny was used as a reference site for comparison of fish physiological responses and seawater quality. Bain des Dames showed high seawater mercury content (6.4+/-0.5 microg/L), traces of iron (70+/-40 microg/L), and fluctuating biochemical oxygen demand values (0.488+/-0.171 mg/L day(-1)). Gill histopathological analysis revealed lesions such as epithelial hyperplasia and inflammation. Similarly, a generalized increase in blood deltaALA-D activity (131.27-355.76 nmol PBG/ml RBC.h) was recorded. Fish from Bain des Dames showed species-specific hematological responses including normocytic macrocytic blood cells (S. ghobban), macrocytic anemia (S. sutor), and active erythropoiesis (E. merra). Though the species displayed impaired health, attributed to changes in water quality, the blood responses seemingly indicate adaptation to hypoxic conditions arising from both gill degradation and perhaps oxygen-level fluctuations.

Macrocytosis--an Australian general practice perspective

BACKGROUND

Clinicians' approaches to identifying and investigating red blood cell macrocytosis are variable. There is little literature on the Australian primary care approach.

METHODS

Mean corpuscular volume (MCV) in blood counts from an urban Australian general practice were calculated and general practitioners in the surrounding division were surveyed on their experience of and approach to investigating macrocytosis.

RESULTS

Mean corpuscular volume above 100 fL was found in 1.7% of patients, and 7.3% had an MCV above 96 fL. Ninety-four percent of responding GPs replied they would further investigate this clinical finding, particularly at levels above 100 fL. Alcohol excess and vitamin B12 deficiency were the most common single causes of macrocytosis in their experience.

DISCUSSION

Macrocytosis can be a marker for disease and it is important to identify and investigate its presence. Further research is needed to clarify the reference range for healthy adults in general practice and to formulate evidence based clinical guidelines for investigating isolated macrocytosis.

Panzytopenie und Hämolyse - Diagnose, Differenzialdiagnose und Therapie der perniziösen Anämie

Pernicious anemia and Vitamin B12 deficiency have a wide range of symptoms and are a common finding in the elderly. A 73 year old female is admitted to the hospital because of dyspnea, fatigue and loss of appetite and weight. While previous medical history and physical examination are inconspicuous, laboratory findings show severe pancytopenia with macrocytosis, low reticulocyte count and marked signs of hemolysis. A very low serum level of vitamin B12 and chronic atrophic type A gastritis upon endoscopy with presence of parietal cell antibodies in the serum lead to the diagnosis of pernicious anemia. Complete restitution is achieved by parenteral vitamin B12 substitution. Nowadays, severe pernicious anemia is only rarely seen. The differential diagnosis of pancytopenia (with macrocytic anemia) combined with hemolysis and the essential hints to the diagnosis of pernicious anemia are discussed, and thereby practical aspects including therapy actualized.

Folate and vitamin B-12 status in relation to anemia, macrocytosis, and cognitive impairment in older Americans in the age of folic acid fortification

BACKGROUND

Historic reports on the treatment of pernicious anemia with folic acid suggest that high-level folic acid fortification delays the diagnosis of or exacerbates the effects of vitamin B-12 deficiency, which affects many seniors. This idea is controversial, however, because observational data are few and inconclusive. Furthermore, experimental investigation is unethical.

OBJECTIVE

We examined the relations between serum folate and vitamin B-12 status relative to anemia, macrocytosis, and cognitive impairment (ie, Digit Symbol-Coding score < 34) in senior participants in the 1999-2002 US National Health and Nutrition Examination Survey.

DESIGN

The subjects had normal serum creatinine concentrations and reported no history of stroke, alcoholism, recent anemia therapy, or diseases of the liver, thyroid, or coronary arteries (n = 1459). We defined low vitamin B-12 status as a serum vitamin B-12 concentration < 148 pmol/L or a serum methylmalonic acid concentration > 210 nmol/L-the maximum of the reference range for serum vitamin B-12-replete participants with normal creatinine.

RESULTS

After control for demographic characteristics, cancer, smoking, alcohol intake, serum ferritin, and serum creatinine, low versus normal vitamin B-12 status was associated with anemia [odds ratio (OR): 2.7; 95% CI: 1.7, 4.2], macrocytosis (OR: 1.8; 95% CI: 1.01, 3.3), and cognitive impairment (OR: 2.5; 95% CI: 1.6, 3.8). In the group with a low vitamin B-12 status, serum folate > 59 nmol/L (80th percentile), as opposed to < or = 59 nmol/L, was associated with anemia (OR: 3.1; 95% CI: 1.5, 6.6) and cognitive impairment (OR: 2.6; 95% CI: 1.1, 6.1). In the normal vitamin B-12 group, ORs relating high versus normal serum folate to these outcomes were < 1.0 (P(interaction) < 0.05), but significantly < 1.0 only for cognitive impairment (0.4; 95% CI: 0.2, 0.9).

CONCLUSION

In seniors with low vitamin B-12 status, high serum folate was associated with anemia and cognitive impairment. When vitamin B-12 status was normal, however, high serum folate was associated with protection against cognitive impairment.

An inherited mutation leading to production of only the short isoform of GATA-1 is associated with impaired erythropoiesis

Acquired somatic mutations in exon 2 of the hematopoietic transcription factor GATA-1 have been found in individuals with Down syndrome with both transient myeloproliferative disorder and acute megakaryoblastic leukemia. These mutations prevent the synthesis of the full-length protein but allow the synthesis of its short isoform, GATA-1s. Experiments in mice suggest that GATA-1s supports normal adult megakaryopoiesis, platelet formation and erythropoiesis. Here we report a mutation, 332G --> C, in exon 2 of GATA1, leading to the synthesis of only the short isoform in seven affected males from two generations of a family. Hematological profiles of affected males demonstrate macrocytic anemia, normal platelet counts and neutropenia in most cases. Altogether, data suggest that GATA-1s alone, produced in low or normal levels, is not sufficient to support normal erythropoiesis. Moreover, this is the first study to indicate that a germline splicing mutation does not lead to leukemia in the absence of other cooperating events, such as Down syndrome.

Macrocytosis associated with divalproex treatment

Divalproex (DVP) is increasingly prescribed to children and adolescents in psychiatric practices. Among the hematologic adverse effects of DVP, decreased platelet count is well described in the medical literature. However, to date, few studies describe the occurrence of macrocytosis as an adverse effect of divalproex. We report two cases of pediatric patients who developed macrocytosis and decreasing platelet counts secondary to DVP treatment. Because macrocytosis remained an asymptomatic nonprogressive condition for our patients, we support the recommendation for closer surveillance of the patients' complete blood counts for development of anemia in addition to thrombocytopenia.

Absence of macrocytic anaemia in Alzheimer's disease

There is an association between Alzheimer's disease (AD) and low serum levels of vitamin B12 and folic acid. Patients also have elevated serum levels of homocysteine and disease progression might therefore be associated with the development of a macrocytic anaemia. We investigated the relationship between disease duration, homocysteine and haematological indices in patients with clinically diagnosed AD and healthy elderly controls. Haemoglobin and platelet counts fell only slightly with increasing dementia duration, but there were no other changes in haematological indices. In particular, macrocytosis and red cell distribution width were unrelated to disease duration and no patients were anaemic. Our results support previous observations that the neurological and haematological features of B12 and folate deficiency are often unrelated in these patients.

The relationship between serum cobalamin concentration and mean red cell volume at varying concentrations of serum folate

There is concern that exposure of patients to folic acid may prevent the development of the macrocytosis of cobalamin deficiency and thus delay the detection of the neurological complications. We examined the relationship between low cobalamin levels and mean cell volume (MCV) at different serum folate concentrations in 63,472 blood samples tested in a community pathology laboratory over 2 years. We found no evidence that high serum folate levels masked the macrocytosis of cobalamin deficiency in this population with similar increases in MCV regardless of whether the serum folate was low, normal or high. Macrocytosis appears to retain its value as a marker of cobalamin deficiency in people with serum folate concentrations above the population average.

Red cell indices for distinguishing macrocytosis of aplastic anaemia and megaloblastic anaemia

Megaloblastic anaemia and aplastic anaemia are important causes of pancytopenia in India. Since both may have presence of macrocytes, peripheral smear examination alone may pose a difficulty in distinction between the two in the absence of macro-ovalocytes and hypersegmented neutrophils. The present study was conducted to evaluate the role of red cell indices in differentiation between macrocytosis of aplastic anaemia and megaloblastic anaemia. Haemogram from 25 cases each of biopsy proven megaloblastic anaemia and aplastic anaemia were reviewed. It was observed that MCV was greater than 97 fl in 15 cases of aplastic anemia (mean MCV 109.7 fl), and 25 cases of megaloblastic anaemia (mean MCV 113.2 fl). Hb, MCV & MCHC were comparable in the two groups. However, mean RDW in megaloblastic anaemia (mean 87.7 fl) was significantly higher than those in aplastic anaemia (mean 71.4 fl). The difference in RDW of patients with megaloblastic anaemia and aplastic anaemia was statistically significant. We conclude that RDW can be of help to differentiate between the two conditions.

Azathioprine-induced fatal macrocytic anemia in rabbits

Azathioprine (AZA) is used clinically sometimes at high doses for short-term therapy to treat acute rejection of kidney allograft or to desensitize hypersensitive patients to it. The delayed consequences of this approach had not been well investigated. Therefore, in this study we have investigated the delayed consequences of high-dose short-term AZA administration in rabbits. Our results showed that oral administration of AZA (10 mg/kg/day) to rabbits for two weeks induced reversible thrombocytosis and delayed fatal macrocytic anemia. Moreover, neither the hemoglobin level nor the white blood cell count was affected by AZA. The solvent of AZA had no effect on blood cell counts and hemoglobin levels. We can conclude that although high-dose AZA therapy may not induce immediate and significant changes in blood picture, delayed fatal macrocytosis may occur.

Response of broiler chicks to dietary Rhazya stricta and Nigella sativa

1. Rhazya stricta leaves and Nigella sativa seeds were fed to 7-d-old Hibro broiler chicks at 20 and 100 g/kg of the diet for 7 weeks. Although 20 and 100 g/kg N. sativa seed diets did not adversely affect growth, a decrease in body weight and feed efficiency and hepatonephropathy were observed in the chicks fed on the 100 g/kg R. stricta diet. 2. These changes, associated with macrocytic hypochromic anaemia, were correlated with alterations in serum aspartate transaminase' (AST) and alanine transaminase (ALT) activities and concentrations of total protein, albumin, globulin, cholesterol, calcium and other serum constituents. 3. The effect of 20 g/kg R. stricta diet on chicks was not associated with development of biliary hyperplasia or catarrhal enteritis after 7 weeks of treatment.

Copper deficiency in Creole goat kids

Serum copper determination is important to confirm hypocupremia. Twenty healthy kids constituted the Control Group, and sixteen kids with symptoms of copper deficiency, the Problem Group. Animals from the Problem Group showed a low number of red blood cells (RBC) and variations in RBC size and shape. The values found for hemoglobin and mean corpuscular hemoglobin (MCH) in the Control Group were 10.42 +/- 1.34 g.dL(-1) and 33.07 +/- 1.11 g.dL(-1) respectively, while the levels of the Problem Group were 7.95 +/- 1.21 g.dL(-1) and 29.45 +/- 0.78 g.dL(-1), respectively. The kids from the Problem Group presented an important increase in monocytes, neutrophiles and leukocytes; precursor cells of the neutrophile were also observed. The anemia of these animals was hypochromic and macrocytic. Our results indicate that Creole kids with serum copper levels > 450 microg.L(-1) improved after treatment with copper glycinate. The six goats with cupremia < 450 microg.mL(-1) were unable to improve their deficiency and died.

Are they microcytes or macrocytes? Can we do a better job?

As an attempt to improve accuracy in the grading of microcytes and macrocytes, a custom reticle was developed and evaluated. The evaluation looked at grading accuracy, reproducibility, speed, and opinion. In this study, the reticle improved the grading accuracy and reproducibility of graders who were "poorer performers." The reticle offered no advantage to the speed of the evaluation. The opinion survey indicated improved confidence with the reticle, and most of the participants found the device useful. The improvement to "poorer performers" is sufficient to warrant use in actual practice.

Pseudohyperkalaemia and pseudomacrocytosis caused by inherited red-cell disorders of the 'hereditary stomatocytosis' group

Unusual dominantly inherited conditions of the red cell, collected under the generic title 'hereditary stomatocytosis and allied disorders', exist, in which the red cell 'leaks' the univalent cations sodium (Na+) and potassium (K+). In some kindreds with these disorders, bizarre temperature effects can occur that have profound effects on the way in which the cells behave when removed from the body and cooled to either room or refrigerator temperatures. In some types, the cells lose K+ at room temperature, giving rise to pseudohyperkalaemia; in others, this occurs in concert with swelling of the red cell and pseudomacrocytosis. In some of these conditions, a red-cell abnormality is clearly demonstrated by the presence of haemolytic anaemia; however, routine haematology can be virtually normal in the milder versions. All are inherited as dominants, although new mutations can be seen.

Feline babesiosis: signalment, clinical pathology and concurrent infections

Fifty-six cats with naturally occurring Babesia felis infection were studied. No breed or sex predilection could be identified, but there was an apparent predilection for young adult cats less than 3 years of age. Macrocytic, hypochromic, regenerative anaemia was present in 57% of the cats and in-saline agglutination tests were positive in 16%. No characteristic changes were observed in total or differential leukocyte counts. Thrombocyte counts were variable and thrombocytopaenia was an inconsistent finding. Hepatic cytosol enzyme activity and total bilirubin concentrations were elevated in the majority of cats. Serum protein values were mostly normal, but increased values were occasionally observed and polyclonal gammopathies were observed in all cats with increased total globulin concentrations. No remarkable changes in renal parameters were observed. A variety of electrolyte abnormalities occurred in a number of cats, but no consistent pattern of change could be identified. A close correlation was evident between peripheral and central parasite counts. Concurrent infections with Haemobartonella felis, feline immunodeficiency virus and/or feline leukemia virus were identified in a number of cats.

Lack of clinical utility of folate levels in the evaluation of macrocytosis or anemia

PURPOSE

Folate levels are routinely ordered in the evaluation of macrocytosis with or without frank anemia, yet the value of these tests is questionable. We evaluated the clinical utility of folate testing in routine clinical practice.

SUBJECTS AND METHODS

We conducted a retrospective review of all serum and erythrocyte folate assays performed over a one-year period at three hospitals. We determined the frequency of low values, then reviewed the medical records of all patients with low values to determine whether low folate levels changed clinician behavior. We also performed a cost analysis to determine the cost of testing per case in which behavior changed.

RESULTS

Only 2.3% of the 2,998 folate levels obtained during the study period were low. The low levels were noted in the record in 53% of cases, and folic acid was prescribed or continued at discharge in only 24%. The cost analysis showed that nearly $10,000 was spent in folate testing per patient in which behavior changed.

CONCLUSIONS

Folate values were rarely low in the population tested, and low values infrequently led to a change in clinician behavior. Given the limited clinical value of folate tests, we propose that, in cases of macrocytosis with or without anemia, to minimize cost and prevent missed cases of true folate deficiency, empirical supplementation with folic acid should be used in place of testing for deficiency.

Hereditary hemochromatosis in a patient with congenital dyserythropoietic anemia

Herein is described the case of a young woman presenting with iron overload and macrocytosis. The initial diagnosis was hereditary hemochromatosis. Severe anemia developed after a few phlebotomies, and she was also found to have congenital dyserythropoietic anemia that, though not completely typical, resembled type II. Only genetic testing allowed the definition of the coexistence of the 2 diseases, both responsible for the iron overload. This report points out the need to consider congenital dyserythropoietic anemia in patients with hemochromatosis and unexplained macrocytosis and, conversely, to check for the presence of hereditary hemochromatosis in patients with congenital dyserythropoietic anemia and severe iron overload. To the authors' knowledge, this is the first report of homozygosity for the C282Y mutation of the HFE gene in a patient affected by congenital dyserythropoietic anemia.

Anemia and macrocytosis in the prediction of serum folate and vitamin B12 status, and treatment outcome in major depression

BACKGROUND

Folate and B12 deficiencies may result in macrocytic anemia, and are common in major depression; hypofolatemia may result in poorer antidepressant response. We wished to determine whether anemia or macrocytosis predict hypofolatemia, low B12, or refractoriness to antidepressants.

METHODS

After obtaining serum folate, B12, and hematological indices, 213 depressed adults were treated with fluoxetine 20 mg/day. Amelioration of depressive symptoms was measured.

RESULTS

Neither macrocytosis nor anemia predicted low serum folate/B12, or antidepressant refractoriness. Among 39 patients with hypofolatemia, none had macrocytosis; 28% had low HCT; 41% had low RBC. Among 25 patients with low B12, none had macrocytosis; 24% had low HCT; 28% had low RBC. Among non-responders, 3% had macrocytosis; 24% had low HCT; 25% had low RBC.

CONCLUSION

Anemia and macrocytosis should not be used to predict folate or B12 deficiencies, or refractoriness to antidepressants. Measurement of folate and B12 should be considered when evaluating treatment refractoriness.

Hematologic abnormalities and acute myeloid leukemia in children and adolescents administered intensified chemotherapy for the Ewing sarcoma family of tumors

PURPOSE

Current treatment of the Ewing sarcoma family of tumors (ESFT) includes intensive multiagent chemotherapy with topoisomerase II inhibitors, alkylating agents, and granulocyte colony-stimulating factor (G-CSF). This treatment approach has been associated with myelodysplasia and acute myeloid leukemia. Because macrocytosis and thrombocytopenia are distinctive features of myelodysplasia, the authors evaluated a cohort of patients treated for ESFT to determine the degree and duration of macrocytosis and thrombocytopenia and their relation with the development of therapy-related hematologic malignancies.

PATIENTS AND METHODS

The study group consisted of 73 patients with ESFT treated on two consecutive protocols (EW92 and EW87). Both chemotherapy regimens incorporated the same agents but differed in cumulative drug dose, dose per course, and the use of G-CSF. Platelet counts and the mean corpuscular volume (MCV) of erythrocytes were determined at diagnosis and during follow-up visits after completion of treatment.

RESULTS

Patients in the EW92 group had significantly greater MCVs after treatment than did the less intensively treated EW87 group. These changes persisted throughout the 40-month observation period. Patients in the EW92 group also had lesser mean platelet counts after treatment than those in the EW87 group. MCV differences (from baseline) were inversely related to platelet counts. The cumulative incidence of treatment-related acute myeloid leukemia was 7.8%+/-4.7% at 4 years in the EW92 group and zero in the EW87 group.

CONCLUSION

Patients treated for ESFT with intensive chemotherapy that includes large doses of alkylators, topoisomerase II inhibitors, and G-CSF characteristically have persistently elevated MCVs and decreased platelet counts after completion of therapy. These hematologic abnormalities may represent stem cell damage, predisposing patients to myelodysplasia and acute myeloid leukemia, but further study is needed to establish this relation.

Etiology and diagnostic evaluation of macrocytosis

BACKGROUND

Elevation of mean cell volume (MCV) is a common clinical problem, but the etiologic spectrum and optimal diagnostic evaluation of macrocytosis are not well defined.

METHODS

We studied 300 consecutive hospitalized adult patients with MCV values > or = 100 fL. Assessment included complete blood counts, morphologic review, liver function tests, and levels of serum cobalamin (Cbl), methylmalonic acid, and total homocysteine.

RESULTS

The most common cause of macrocytosis was drug therapy, followed by alcohol, liver disease, and reticulocytosis. Megaloblastic hematopoiesis accounted for less than 10% of cases. MCV values > 120 fL were usually caused by Cbl deficiency. Anisocytosis, macro-ovalocytosis, and teardrop erythrocytes were most prominent in megaloblastic hematopoiesis. Elevated levels of serum methylmalonic acid and total homocysteine were useful in the diagnosis of Cbl deficiency.

CONCLUSIONS

Drugs and alcohol are the most common causes of macrocytosis in hospitalized patients in a New York City teaching hospital. We have formulated tentative guidelines for the evaluation of high MCV values in this setting.

Quantitative determinations of microcytic-hypochromic red blood cell population and glycerol permeability in iron-deficiency anemia and beta thalassemia minor

The Hl/H2 Technicon automated cell analyzer measures, in addition to the usual red blood cell (RBC) parameters, subpopulations of microcytic (M) and hypochromic (H) red blood cells. The M/H ratio may be useful in the differential diagnosis of iron-deficiency anemia (IDA) and beta thalassemia minor (Thal). Thirty-three iron-deficient patients and 26 thalassemia patients were studied. The M/H ratio was found to be higher in thalassemia patients than in IDA patients. Using a cut-off point of 1.9 M/H ratio, the calculated discriminant efficiency was 88%. When glycerol lysis values were determined at 70 s as a cut-off point, the discriminant efficiency was slightly higher, at 91%. Thus, the combination of the M/H ratio and the glycerol lysis time (GLT) improves the discriminant efficiency and provides a good diagnostic tool to differentiate between the two microcytic-hypochromic anemias. The study suggests that the M/H ratio together with the GLT could serve as a useful screening tool, prior to the application of other more sophisticated methods.