Whole blood viscosity in beta thalassemia minor.

Patients with heterozygous beta-thalassemia minor have a decreased hematocrit (HCT). Since the HCT is a primary determinant of whole blood viscosity, the known reduction in HCT in beta-thalassemia minor should lead to a measurable reduction of whole blood viscosity. The influence of the relatively lower mean corpuscular volume and consequent higher red blood cell count and beta-thalassemia minor on whole blood viscosity using a microporous viscometer has not previously been the subject of investigation. Accordingly, the blood of a group of normal and beta-thalassemia minor subjects was examined with a microporous viscometer to elucidate further the relations between whole blood viscosity, HCT, and red blood cell count. The data show that for normal and beta-thalassemia minor subjects a significant positive correlation (r = 0.65, p less than 0.01) exists between HCT and whole blood viscosity. However, the slope of the regression of whole blood viscosity and HCT of beta-thalassemia minor subjects was significantly higher z = 3.14, p less than 0.001) than that of normals. Thus, for any given HCT their whole blood viscosity was higher than that of normals. Studies of the relation of red blood cell counts to whole blood viscosity indicate the higher whole blood viscosity at a given HCT was related to the increased red blood cell counts in beta-thalassemia minor subjects. Because of the opposing interactions of HCT and red blood cell counts, the mean whole blood viscosity of the group of beta-thalassemia minor subjects examined was not significantly lower than the normal whole blood viscosity.(ABSTRACT TRUNCATED AT 250 WORDS)     

Red cell indices and serum ferritin levels in children.

The blood counts of 187 non-anaemic children who attended hospital with minor illnesses and who were between the ages of 12 months and 6 years were studied retrospectively. As many as 76-8% of these children were found to have MCVs below the normal adult range. A prospective study of a further 28 non-anaemic children in the same age group showed that the majority of children with low MCVs have normal haemoglobin A2 and F levels and have serum ferritin levels within the normal adult range. These findings indicate that microcytosis is an intrinsic feature of erythropoiesis in early childhood and that in most instances this feature cannot be attributed to iron deficiency or beta-thalassaemia syndromes.     

Usefulness of certain red blood cell indices in diagnosing and differentiating thalassemia trait from iron-deficiency anemia

Iron-deficiency anemia and thalassemia are among the most common microcytic anemias. Differentiating these anemias by means of hemogrant indices is imprecise. Powerful statistical computer programming now enables sensitive discriminant analyses to aid in the diagnosis. Laboratory results from 383 adults were examined retrospectively and grouped according to their original diagnoses: normal (n = 78); beta-thalassemia (n = 134); alpha-thalassemia (n = 106); and iron-deficiency anemia (n = 65). Statistical analysis of results evaluated only RBC indices: RBC count, hemoglobin level, mean corpuscular volume, mean corpuscular hemoglobin, and RBC distribution width. Stepwise multivariate discriminant analysis determined those indices that best differentiated the 4 groups. The Fisher linear discriminant function for each group was calculated and tested casewise. Discriminant analysis identified mean corpuscular hemoglobin, RBC count, mean corpuscular volume, and RBC distribution width as the best set of indices for differentiating the 4 diagnoses. Casewise testing of the calculated Fisher linear discriminant function resulted in mean-weighted sensitivity of 80.4%. The present study demonstrates that a set of linear discriminant functions based on routine hemogram data can effectively differentiate between alpha-thalassemia, beta-thalassemia, and iron-deficiency anemia, with a high degree of accuracy.     

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.     

Leg ulcer in a case of thalassemia minor (a case report)

A rare case of leg ulcer in a 28 years old woman with thalassemia minor is reported.     

轻型地中海贫血孕妇妊娠晚期贫血的其他相关因素探讨

目的探讨轻型地中海贫血孕妇妊娠晚期贫血的其他相关因素,揭示妊娠期铁(Fe)、维生素B12(Vit B12)、叶酸(Fol)的代谢状况,旨在为临床提高轻型地中海贫血孕妇血红蛋白水平提供理论依据。方法选取在我院定期产检的孕28～40周孕妇84例,α地贫23例(A组)、β地贫21例(B组)、100g/L<血红蛋白(HGB)<110g/L 19例(C组)、HGB≥110g/L 21例(D组)。所有病例检测血红蛋白(HGB)、血清铁蛋白(SF)、血清维生素B12(Vit B12)、血清叶酸(Fol),同时对各项指标进行统计分析。结果①A组HGB较B组高(P<0.05),A组发生贫血风险是B组的0.285倍。②SF比较:除A组低于D组(P<0.05)、B组高于C组(P<0.05)、C组低于D组(P<0.05)外,其余各组间比较P>0.05。Fol、Vit B12在四组间比较P>0.05。③储铁缺乏率:A组高于D组(P=0.0048);C组高于D组(P=0.0016);储铁减少率四组间比较P>0.05。④储铁缺乏风险:A组是D组的3.196倍(P<0.05);C组是D组的3.592倍(P<0.05)。储铁减少风险:B组是C组的0.704倍(P<0.05);C组是D组的1.530倍(P<0.05)。结论①轻型地贫并不增加晚期妊娠孕妇铁负荷,与正常孕妇一样可出现铁缺乏;②β地贫低HGB水平较α地贫多,提示β地贫孕妇更应该密切动态关注HGB水平,分析贫血的其他相关因素;③α地贫孕妇缺铁风险较非贫血的正常孕妇高,应高度重视合理的铁补充;④地贫孕妇出现HGB降低,且存在SF低时,在实验室的监测下补铁是安全的;⑤HGB 100～110 g/L时,即是缺铁的高危界限,此时及时补铁,可防止HGB进行性降低致妊娠期贫血;⑥Vit B12、Fol与晚期妊娠轻型地贫贫血无明显相关性。     

Basal cell adenocarcinoma in minor salivary glands

Basal cell adenocarcinoma is a rare and relatively recently characterized malignant salivary gland tumour, the malignant counterpart of basal cell adenoma. Diagnosis depends on finding features similar to adenoma but with an infiltrative growth pattern and exclusion of adenoid cystic carcinoma, sialoblastoma and basaloid squamous carcinoma. Basal cell adenocarcinoma is very rarely reported in minor salivary glands. We report three cases of basal cell adenocarcinoma affecting the labial, buccal and palatal minor salivary glands. One recurred following complete removal but with lesional disruption and further local wide excision appeared curative. A further lesion failed to recur in 5 years' follow-up despite marginal excision and a third after 3 years' follow-up. Basal cell adenocarcinoma is considered a low-grade malignancy, and in the minor glands wide excision and radiotherapy are recommended. However, the reported lesions appear to have a more indolent behaviour than previously reported lesions in minor glands.     

Red cell distribution width in sickle cell disease

Red cell distribution width (RDW), an electronically determined index of anisocytosis, was examined in 60 patients with sickle cell anemia (Hb SS), 28 patients with hemoglobin sickle cell (SC) disease, and seven patients with sickle cell-beta(+) thalassemia (S-thal). All patients were adults and in the steady state of their disease. The RDW was greater in sickle cell patients than in 39 healthy, age and race matched controls without hemoglobinopathy (Hb AA). Patients with sickle cell anemia had higher mean RDW than those with Hb SC disease or with S-thal. The mean RDWs in the latter two disorders were not significantly different. In SS patients, the RDW correlated significantly with the degree of anemia and reticulocytosis. A group of 18 SS patients was studied while in acute painful crisis. Their mean RDW was not different from that in the steady state. Mean WBC and red cell volume, however, were significantly higher during pain crisis.     

Racial differences in red cell indices.

A high prevalence of iron deficiency was found in apparently healthy Asian immigrant children in Harrow. After excluding children with overtly abnormal red cell indices, Asian and European children had identical haemoglobin values, but Asian children had much lower mean cell volume and mean corpuscular haemoglobin values and higher red blood cell values.     

Premarital screening for thalassemia and sickle cell disease in Saudi Arabia

PurposeTo estimate the prevalence of sickle cell disorders and beta thalassemia, with their regional distribution, in the adult population screened as part of the Saudi Premarital Screening Program.MethodsA cross-sectional, population-based study was conducted as part of the National Premarital Screening Program. It covered all the individuals who applied for a marriage license during the years 1425 and 1426 Hijra (February 2004 to January 2005). A network of 123 reception centers in the Ministry of Health facilities and 70 laboratories all over Saudi Arabia was involved in data collection.ResultsOf a total of 488,315 individuals screened, 4.20% had sickle cell trait, 0.26% had sickle cell disease, 3.22% had thalassemia trait, and 0.07% had thalassemia disease. Both the diseases were focused mainly in the eastern, western, and southwestern parts of the country. Among the 207,333 couples who were issued certificates for matching, 2.14% were declared high risk. Among the 2,375 high-risk couples contacted by telephone, 89.6% married each other, despite the known high-risk status.ConclusionThe results showed excellent access to the target population. However, the program's objective of decreasing high-risk marriages was not as successful, indicating the need for improvement of health education programs for the public, more efforts in counseling high risk couples, and changes in the strategy of timing of screening in relation to marriage.     

Alpha thalassemia among sickle cell anaemia patients in Kampala,Uganda

Background

Sickle cell anaemia is prevalent in sub Saharan Africa. While α+-thalassaemia is known to modulate sickle cell anaemia, its magnitude and significance in Uganda have hitherto not been described.

Objectives

To determine the prevalence of α+thalassaemia among sickle cell anaemia patients in Mulago Hospital and to describe the clinical and laboratory findings in these patients.

Methods

A cross sectional study was carried out on patients with sickle cell anaemia in Kampala. Dried blood spots were used to analyze for the deletional α+ thalassaemia using multiplex polymerase chain reaction.

Results

Of the 142 patients with sickle cell anaemia, 110 (77.5%) had the αα+thalassaemia deletion. The gene frequency of (−α) was 0.425. Ninety one percent (100/110) of those with α+thalassaemia were heterozygous (αα/α-). Amongst the patients older than 60 months, 15 (83.3%) of those without αα+thalassaemia had significant hepatomegaly of greater than 4 cm compared to 36 (45.6%) of those with α+thalassaemia (p=0.003).

Conclusion

The gene frequency of (−α) of 0.425 noted in this study is higher than that reported from many places in Africa. Concurrent alpha thalassemia might be a protective trait against significant hepatomegaly in sickle cell anaemia patients more than 60 months of age at Mulago hospital.     

Red blood cell proteomics

Since its discovery in the 17th century, the red blood cell, recognized in time as the critical cell component for survival, has been the focus of much attention. Its unique role in gas exchange (oxygen/CO₂ transport) and its distinct characteristics (absence of nucleus; biconcave cell shape) together with an – in essence – unlimited supply lead to extensive targeted biochemical, molecular and structural studies. A quick PubMed query with the word “erythrocyte” results in 198 013 scientific articles of which 162 are red blood cell proteomics studies, indicating that this new technique has been only recently applied to the red blood cell and related fields. Standard and comparative proteomics have been widely used to study different blood components. A growing body of proteomics literature has since developed, which deals with the characterization of red blood cells in health and disease. The possibility offered by proteomics to obtain a global snapshot of the whole red blood cell protein make-up, has provided unique insights to many fields including transfusion medicine, anaemia studies, intra-red blood cell parasite biology and translational research. While the contribution of proteomics is beyond doubt, a full red blood cell understanding will ultimately require, in addition to proteomics, lipidomics, glycomics, interactomics and study of post-translational modifications. In this review we will briefly discuss the methodology and limitations of proteomics, the contribution it made to the understanding of the erythrocyte and the advances in red blood cell-related fields brought about by comparative proteomics.