Serum Lactate Dehydrogenase Isoenzyme Pattern in non-Hodgkin's lymphomas

Serum lactate dehydrogenase (S-LDH) and its isoenzyme pattern were assayed in 63 non-Hodgkin's lymphoma (NHL) patients, 37 at diagnosis, 15 at relapse and 11 in complete remission (CR). S-LDH in NHL patients with active disease was higher than in normal subjects and CR patients (p<0.001). Among the isoenzymes, LDH-2 and LDH-5 showed no remarked differences; LDH-1 was reduced and LDH-3 and LDH-4 raised in comparison to the normal group (p<0.001). S-LDH levels and isoenzymes 1 and 4 were influenced by the stage, the histological subgroup and by the presence of general symptoms. In fact, cases in stage IV, with “high-grade malignancy” and with general symptoms, had higher S-LDH levels and more evident LDH-1 and LDH-4 changes than the other stages, the other histopathological subgroups and the cases classified as “A”. S-LDH was the same as in normal subjects in the “low-grade” and “intermediate-grade” malignancies as was LDH-1 in stage II and LDH-4 in stages II and III, in “low-grade” malignancy and in the A cases. In contrast, LDH-3 was always high, with no significant difference in relation to the variables considered.

Thus, in NHL, LDH-3 seems to be a reliable marker of the presence of the disease in any case, whereas S-LDH is more related to the spread of the lymphoma.

EPO modulation in a 14-days undersea scuba dive

Erythropoiesis is affected during deep saturation dives. The mechanism should be related to a downregulation of serum Erythropoietin (s-EPO) concentration or to a toxic effect of the hyperbaric hyperoxia. We evaluated s-EPO and other haematological parameters in 6 scuba divers before, during and after a 14-days guinness saturation dive (8-10 m). Athletes were breathing air at 1.8-2 ATA, under the control of a team of physicians. Serum parameters were measured before diving (T0) and: 7 days (T1), 14 days (T2) after the beginning of the dive and 2 h (T3) and 24 h (T4) after resurfacing. Hgb, and many other haematological parameters did not change whereas Ht, s-EPO, the ratio between s-EPO predicted and that observed and reticulocytes (absolute, percent) declined progressively from T0 to T3. At T4 a significant rise in s-EPO was observed. Hgb did not vary but erythropoiesis seemed to be affected as s-EPO and reticulocyte counts showed. All these changes were statistically significant. The experiment, conducted in realistic conditions of dive length, oxygen concentration and pressure, allows us to formulate some hypotheses about the role of prolonged hyperbarism on erythropoiesis. The s-EPO rise, 24 h after resurfacing, is clearly documented and related to the "Normobaric Oxygen Paradox". This evidence suggests interesting hypotheses for new clinical applications such as modulation of s-EPO production and Hgb content triggered by appropriate O₂ administration in pre-surgical patients or in some anemic disease.

Iron, zinc and aluminium ferritin content of hemodialysis hyperferritinemic patients: comparison with other hyperferritinemic clinical conditions and normoferritinemic blood donors

The present study describes the specific content of ferritin iron, zinc and aluminium in four different groups: 1) hemodialysis hyperferritinemic patients; 2) septic patients; 3) iron overloaded patients with hematologic diseases; and 4) blood donors. In all four groups high levels of aluminium and zinc were found in addition to those of iron. However, the sum of the ferritin ions of the control group is significantly higher than that of the other three groups. Furthermore, while ferritin of hemodialysis patients has the same molecular ratio of metal ions as control group (high Al content vs. Fe and Zn), a lower Al/Fe ratio is found both in septic and hematological patients. The results of the present paper might help to explain the high percentage of hyperferritinemia found in hemodialysis patients also in presence of low transferrin saturation and in absence of inflammatory markers. Moreover, the high content of ions other than iron in the ferritin core leads us to believe that ferritin is not only an iron storage protein but rather a regulator of redox active ions.

Modulation of the expression and activity of cyclooxygenases in normal and accelerated erythropoiesis

OBJECTIVE

The present study was aimed at characterizing the expression and activity of cyclooxygenase (COX) isoenzymes in erythropoiesis.

METHODS

The expression and activity of cyclooxygenase (COX) and prostaglandin (PG) synthases were investigated in: 1) erythroblasts developed in culture from human CD34(+) hematopoietic progenitors, 2) erythroblasts in bone marrow specimens, and 3) peripheral erythrocytes isolated from healthy donors and from patients with a high regeneration rate of erythrocytes.

RESULTS

While COX-1 protein was observed at each stage of erythroblast development, COX-2 protein was induced at later stages through a p38/MAPK-dependent pathway. Both COX isoforms were also observed in mature erythroblasts of the bone marrow. Erythroblasts developed in culture synthesized significantly more PGE(2) than TXB(2) and indomethacin delayed erythroid maturation. COX-1 and COX-2 were also observed in erythrocytes by immunostainings, although COX expression was confined to a fraction of circulating erythrocytes. Peripheral erythrocytes synthesized low but detectable amounts of PGE(2) and TXB(2). Similarly to erythroblast progenitors, PGE(2) was the prevalent prostanoid released by erythrocytes. This biosynthetic capacity was significantly increased in erythrocytes from patients with accelerated erythropoiesis as compared to controls.

CONCLUSIONS

Both COX isoforms are present and enzymatically active during human erythropoiesis, although with different kinetics, and COX-derived prostanoids may play a role in erythroid maturation. Furthermore, peripheral erythrocytes retain in part the capacity of expressing COX and synthesizing prostanoids, which may contribute to the hemostatic/thrombotic response to vascular injury in different diseases, including congenital hemolytic disorders.

Reduced serum levels of immunoreactive erythropoietin in patients with cirrhosis and chronic anemia

Chronic anemia is frequently observed in patients affected by cirrhosis. To investigate the possible role of erythropoietin (Epo) in the pathogenesis of anemia in cirrhosis, we measured the immunoreactive Epo levels and the respective hemoglobin (Hb) concentrations in 48 anemic and nonanemic cirrhotic patients and in a control group of healthy subjects and patients with iron-deficiency anemia. Epo concentrations were determined in serum using a sensitive enzyme immunoassay. The regression curve between Epo values and Hb concentrations showed a significant inverse exponential trend both in cirrhotic patients (r = -.55; P < .0001) and controls (r = -.92; P < .0001). In a semilogarithmic plot, the line slope obtained in cirrhotic patients was significantly lower (P < .005) than that of controls, suggesting a blunt Epo response to anemia in cirrhosis. Moreover, covariance analysis showed that the Epo levels for a given degree of anemia were further reduced in the patients with a more severe disease, suggesting a close relation between cirrhosis and the mechanisms involved in the derangement of the Epo feedback system. Finally, the Epo concentrations measured in the cirrhotic patients without anemia did not significantly differ from Epo values obtained in healthy subjects. An impaired Epo response may play a role in maintaining low Hb concentrations in cirrhotic patients with anemia. However, the evidence of a residual Epo response to anemia in cirrhosis and the presence of normal basal Epo levels in nonanemic cirrhotic patients do not support an inadequate Epo secretion as one of the primary causes of anemia in cirrhosis.

Reduced serum levels of immunoreactive erythropoietin in patients with cirrhosis and chronic anemia

Chronic anemia is frequently observed in patients affected by cirrhosis. To investigate the possible role of erythropoietin (Epo) in the pathogenesis of anemia in cirrhosis, we measured the immunoreactive Epo levels and the respective hemoglobin (Hb) concentrations in 48 anemic and nonanemic cirrhotic patients and in a control group of healthy subjects and patients with iron-deficiency anemia. Epo concentrations were determined in serum using a sensitive enzyme immunoassay. The regression curve between Epo values and Hb concentrations showed a significant inverse exponential trend both in cirrhotic patients (r = -.55; P < .0001) and controls (r = -.92; P < .0001). In a semilogarithmic plot, the line slope obtained in cirrhotic patients was significantly lower (P < .005) than that of controls, suggesting a blunt Epo response to anemia in cirrhosis. Moreover, covariance analysis showed that the Epo levels for a given degree of anemia were further reduced in the patients with a more severe disease, suggesting a close relation between cirrhosis and the mechanisms involved in the derangement of the Epo feedback system. Finally, the Epo concentrations measured in the cirrhotic patients without anemia did not significantly differ from Epo values obtained in healthy subjects. An impaired Epo response may play a role in maintaining low Hb concentrations in cirrhotic patients with anemia. However, the evidence of a residual Epo response to anemia in cirrhosis and the presence of normal basal Epo levels in nonanemic cirrhotic patients do not support an inadequate Epo secretion as one of the primary causes of anemia in cirrhosis.

Serum transferrin receptors in rheumatoid arthritis

OBJECTIVE

Serum transferrin receptors (sTfR) were determined in patients affected by rheumatoid arthritis (RA) to verify a possible relationship with the degree of anaemia and with the severity of the inflammatory disease.

METHODS

sTfR, IL1-b, TNF-a and common parameters of iron metabolism were studied in 72 patients with active RA. Anaemia (Hb < 12 g/dl) was present in 51 patients. Twenty normal healthy subjects and 40 iron-deficient anaemic patients without chronic inflammatory, infective or malignant diseases were studied as controls.

RESULTS

In patients with RA sTfR levels were significantly higher than in the normal group but lower than in iron-deficient anaemic patients and correlated positively with ESR and IL1-b and negatively with Hb. Anaemic patients with RA were divided into two groups. Group A (56%) showed a possible iron deficiency (TSI < 16 and ferritin < 50 ng/ml); group B did not show iron deficiency (TSI > 16 and ferritin > 50 ng/ml). No significant difference in sTfR was observed in the two groups.

CONCLUSION

sTfR appear to be elevated and related to the degree of anaemia and to the inflammatory process in RA. Reduced sTfR levels in patients with RA compared with patients with iron-deficiency anaemia may indicate a reduced erythropoietic activity in RA.

Automated measurement of red blood cell microcytosis and hypochromia in iron deficiency and beta-thalassemia trait

Some routine red blood cell (RBC) measurements and indexes (count, mean volume, volume dispersion, and mean hemoglobin [HGB] concentration) can be used to differentiate iron deficiency from heterozygous beta-thalassemia. A number of formulas that incorporate two or more of these measurements have been described to amplify such differences. The H*1 hematology analyzer directly measures volume and HGB concentration of individual RBCs. We have assessed the diagnostic usefulness of conventional and new RBC measurements provided by the H*1 on a learning data set that comprised 119 patients with iron deficiency and 172 patients with beta-thalassemia trait, both untreated and uncomplicated. The most striking finding was the inverse behavior of percentages of microcytes (volume, less than 60 fL) and hypochromic RBCs (HGB concentration, less than 280 g/L) in the two conditions. In 162 of 172 patients with beta-thalassemia trait, the percentage of microcytes (mean, 33.1%; central 95th percentile range, 9.2% to 54.5%) was higher than the percentage of hypochromic RBCs (mean, 13.9%; central 95th percentile range, 1.7% to 24.7%). In 105 of 119 patients with iron deficiency, on the contrary, the percentage of hypochromic cells (mean, 34.6%; central 95th percentile range, 9.7% to 73.1%) was higher than the percentage of microcytes (mean, 12.8%; central 95th percentile range, 1.7% to 29.6%). The ratio between the percentage of microcytes and the percentage of hypochromic cells provided by the H*1 (microcytic-hypochromic ratio) was useful in differentiating the two types of microcytic anemia: with the use of a discriminant value of 0.9, the discriminant efficiency of the microcytic-hypochromic ratio was 92.4% (95% confidence interval, 88.8% to 95.2%), higher than that of the five previously described discriminant formulas and simple RBC measurements. When assessed on a test data set that comprised 149 unselected cases of microcytic anemia, a microcytic-hypochromic ratio lower than 0.9 demonstrated high sensitivity (94.0%), specificity (92.3%), and predictive value (94.0%) for the presence of iron-deficient erythropoiesis in patients with isolated iron deficiency, polycythemia vera treated by phlebotomy, and iron deficiency complicating heterozygous thalassemia. In conclusion, our results showed that iron-deficient erythropoiesis is characterized by the production of RBCs with a severely decreased HGB concentration, while microcytes of beta-thalassemia trait are generally smaller, with a more preserved HGB concentration. Such properties, as assessed by the H*1 hematology analyzer, are very useful in distinguishing these two common types of microcytic anemia.

Ph1-chromosome-positive chronic myelogenous leukemia following a 1-year 'off-therapy' acute lymphoblastic leukemia

In this paper we describe a patient with acute lymphoblastic leukemia followed after 4 years by a Ph1-positive chronic myelogenous leukemia. The possible relationship between these two diseases is discussed.

Cerebrospinal fluid beta-2-microglobulin: a reliable index of leukaemic infiltration of central nervous system

Cerebrospinal fluid (CSF) beta-2-microglobulin (B2m) has been proposed as a marker of central nervous system (CNS) involvement in myelo-lymphoproliferative diseases. Recently its reliability has been put in question because of false positive and false negative results. In our study, B2m was measured in 574 CSF samples collected from 74 patients affected by ALL, ANLL or lymphomas; 20 of these patients had CNS-involvement while they were under observation. There was a significant difference in CSF B2m between the patients with and without CNS-involvement (p less than 0.001). No false positive or false negative results were obtained. In 4 cases the rising of CSF B2m was observed 8, 6, 4 and 4 wk before the clinical and laboratory diagnosis of CNS-involvement. In all patients the clinical and laboratory improvement of the neurological disease was associated with a progressive decrease of CSF B2m. Some hypotheses about the origin of CSF B2m are discussed. The authors conclude that CSF B2m is a useful and reliable marker of CNS-involvement in myelo-lymphoproliferative disease.