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To examine the effects of unusual or atypical beta-globin gene cluster haplotypes on the hematological features and Hb F levels of sickle cell anemia, we studied African Americans who had an atypical or Cameroon haplotype chromosome in association with a typical haplotype. We identified over 20 atypical haplotypes. The distribution of 5' sub-haplotypes of the atypical chromosomes mirrored the distribution of common haplotypes in African Americans with sickle cell anemia. Neither 5' nor 3' subhaplotypes of the atypical chromosomes affected Hb F levels, packed cell volume, or mean corpuscular volume in individuals with a Benin chromosome. That the 5' subhaplotype is unaffected might be a consequence of the small numbers of Senegal 5' subhaplotypes in our sample, the need for linkage of both 5' and 3' subhaplotypes of any haplotype for an effect on Hb F to be present, or the likelihood that a normal beta-globin gene contributed the 5' subhaplotypes of some atypical haplotypes.

Cardiac function was measured at rest and during exercise in 9 patients with sickle-cell anemia (SS) and coexisting homozygous alpha thalassemia-2 (alpha thal-2). Results were compared with 18 sickle cell patients with normal alpha globin genes, who were matched to the study group by age, gender, and size, and to published normal values. SS alpha thal-2 patients were less anemic: 9.9 +/- 1.0 vs 8.2 +/- 1.2 gm/dl for SS alone (P.05). Left ventricular dimensions were normal in SS alpha thal-2 (4.9 +/- 0.7 cm), but increased in SS (5.4 +/- 0.7, cm P=.05) (normal range, 3.7-5.6 cm). Left ventricular wall thickness was, however, dramatically increased in the SS alpha thal-2 patients (free wall, 1.8 +/- 0.6 cm; septum, 1.6 +/- 0.4 cm), though SS controls had normal wall thickness (free wall, 1.0 +/- 0.2 cm; septum, 1.0 +/- 0.2 cm, P.001) (normal range, 0.6-1.1 cm). At rest, Doppler indices of systolic function were not significantly different between sickle groups and normal values. SS alpha thal-2 patients did have abnormal diastolic filling at rest, as evidenced by a reduced ratio of early/late diastolic filling, 1.4 +/- 0.3 vs. 2.0 +/- 0.5 for SS controls (P.01), and 1.8 +/- 0.4 for normals. An analysis of covariance suggested that this abnormality persisted after taking into account the previously demonstrated hypertrophy. During exercise, SS alpha thal-2 patients had higher heart rates and blood pressures than SS controls in spite of performing the same or less work. This resulted in a higher double product (an estimate of oxygen consumption) in SS alpha thal-2 patients (37,470 +/- 2,310 mm Hg-BPM) than in SS controls (33,310 +/- 1,490 mm Hg-BPM, P.01). Work capacity, peak heart rate, and blood pressure were all abnormally decreased in both sickle-cell groups when compared to normal. Cardiac abnormalities noted at rest and during exercise in SS alpha thal-2 patients suggest a role of microvascular occlusion and a protective effect of decreased hemoglobin.

The prevalence and incidence of osteonecrosis (ON) of the humeral head in sickle cell disease was determined by a study of 2524 patients who were entered into a prospective study and followed for an average of 5.6 years. At entry, 5.6% had roentgenographic evidence of ON in one or both shoulders. There was little difference in age-adjusted prevalence among genotypes, but there were striking differences in age-specific rates. Observed at ages ranging from five to 24 years, 3.25% of sickle cell anemia (S/S) patients, but only 1.1% of sickle cell disease (S/C) patients, had ON. No S/beta+ thalassemia patients younger than 25 years of age had ON on entry. The highest age-adjusted incidence rate was found in S/S patients with concomitant alpha-thalassemia (4.85 per hundred patient-years), followed by S/beta zero-thalassemia (4.84 per hundred patient-years), S/beta+ thalassemia (2.61 per hundred patient-years), S/S without alpha-thalassemia (2.54 per hundred patient-years), and S/C (1.66 per hundred patient-years). Only 20.9% of patients reported pain or had limited range of movement at the time of diagnosis. Sickle cell disease is a frequent cause of ON of the humeral head, especially in children and young adults.

Patients with sickle cell anemia were treated with daily doses of hydroxyurea, to assess pharmacokinetics, toxicity, and increase in fetal hemoglobin (Hb) production in response to the drug. Plasma hydroxyurea clearances were not a useful guide to maximum tolerated doses of the drug. The mean daily single oral dose that could be maintained for at least 16 weeks was 21 mg/kg (range, 10 to 35 mg/kg). Among 32 patients, last HbF levels were 1.9% to 26.3% (mean, 14.9%) with increases in HbF over initial values of 1.4% to 20.2% (mean, 11.2%). The most significant predictors of last HbF were last plasma hydroxyurea level, initial white blood count and initial HbF concentration. Last HbF was not related to beta globin haplotype or alpha globin gene number. No serious toxicity was encountered. Clinically significant bone marrow depression was avoided, and chromosome abnormalities after 2 years of treatment were no greater than those observed before treatment. The period of observation has been too short to evaluate the risk of carcinogenesis. Patient's red cells developed striking macrocytosis. Median red cell Hb concentrations did not change. Hb concentrations increased, on average 1.2 g/dL, but serum erythropoietin levels increased. Patients' body weights increased, and some returned to work or school, but no conclusions regarding therapeutic efficacy could be drawn from this uncontrolled open-label study.

The syndrome thalassemia intermedia can be the clinical expression of heterozygosity for different tyes of thalassemia, beta-thalassemia and hereditary persistence of fetal hemoglobin, beta-thalassemia and Hb-Lepore, and in blacks it may even represent a true beta-thalassemia homozygote. This report describes thalassemia intermedia in a white male due to beta-thalassemia and an unstable hemoglobin. Chain-synthesis studies showed an excess of alpha-chain production over beta-chain production in the propositus and his mother but balanced chain synthesis in the clinically normal father, who is heterozygous for the unstable hemoglobin. The unstable hemoglobin was found to be beta14 (A11) Leu leads to Pro, which has previously been described in a clinically normal African woman, and named Hb-Saki. This hemoglobin is not distinguishable from Hb-A on routine electrophoresis at alkaline or acid pH and tests for unstable hemoglobins are necessary for its detection. The increasing list of such hemoglobin variants and previous cases of heterozygosity for beta-thalassemia and unstable hemoglobins are reviewed.

Members of 7 large families, containing 20 patients with sickle cell anemia (SS) characterized by high levels of fetal hemoglobin (HbF), were studied using immunofluorescence to count F cells and a radioimmunoassay to measure small amounts of HbF. In five of these families, one of the sickle cell trait (AS) parents had a much higher HbF and F-cell count than the other; in one family, both parents had a marked increase in HbF and F cells; in the remaining family, HbF and F cells were at borderline values in both parents. Seven of 14 AS siblings, but only 1 of 8 normal hemoglobin (AA) siblings, also had HbF and F-cell counts above the “normal” range. It seems that a factor for increased F cells, linked to the beta S gene of one parent, is segregating in these families and is responsible for the greatly increased HbF and F cells in the SS subjects. HbF per F cell in AS parents and siblings was the same as that of normal AA subjects, whereas in the SS offspring it was greatly increased, suggesting that it was the result of marrow hyperplasia associated with their hemolytic anemia. The similarity of this “increased F-cell gene” to heterocellular hereditary persistence of fetal hemoglobin (HPFH). Swiss type, is discussed, and it is suggested that it may control the persistent synthesis of HbF in sickle cell anemia by its presence in early infancy.

We describe ten patients with sickle cell anemia who became acutely ill within a few days after a blood transfusion. Two patients died. In eight cases the posttransfusion detection of alloantibodies suggested that delayed hemolytic reactions to transfusion were involved in precipitating the acute illness. In some cases the illnesses mimicked vaso-occlusive crises, with bone marrow infarction, while in other cases transient biliary obstruction or transient renal insufficiency was documented. Profound anemia mimicked aplastic crises, but we observed a remarkable capacity of the bone marrow to restore the hemoglobin level without further transfusion. In view of the prevalence of delayed hemolytic transfusion reactions in these patients receiving frequent transfusions and whose red cell antigens differ from those of the white population, we suggest that efforts to more closely match recipient and donor red cell antigens would be clinically, technically, and financially advantageous. Moreover, criteria for transfusion in sickle cell anemia should be strictly scrutinized. Quantitation of transfused hemoglobin A has proved useful in confirming delayed hemolytic reactions in sickle cell disease.

The proportion of Hb G Philadelphia (alpha68-Asn leads to Lys) in heterozygotes has been found to have a well-defined bimodal distribution around means of 33% and 46% Hb G. microcytosis and hypochromia are consistently associated with the latter group, who also have a decreased ratio of alpha/beta-chain synthesis in the peripheral blood, but these characters are not linked to the Hb-Galpha gene, because a parent with microcytosis and 46% Hb Galpha may have offspring with 33% Hb G without significant microcytosis. In one family a subject with Hb G and Hb G2 but no Hb A or Hb A2 is presumably a homozygote for alphaG. This subject has microcytosis and a decreased ratio of alpha/beta chain synthesis. In another family a subject with Hbs H, G and G2 but without Hbs A or A2 is heterozygous for both Hb G and alpha thalassaemia I. These findings are compatible with the hypothesis that the alphaG mutation occurs on a chromosome with only a single alpha-chain locus and that the expression in heterozygotes as 46% or 33% Hb G is determined by the homologous chromosome in trans having either one or two normal alphaA genes respectively. The significance of this polymorphism for chromosomes carrying alpha-chain genes is discussed.

Five families are described in which there have been matings between individuals doubly heterozygous for beta thalassaemia and the delta-chain variant haemoglobin A2' to normal persons. In all there were 24 informative offspring. There were no crossovers between the beta-thalassaemia and delta-chain loci; in three of the families the genes were linked in cis and in two families the genes were found in trans. Together with previously reported families there have now been 58 opportunities for crossing over between the beta-thalassaemia and delta-chain loci and there have been two possible and one highly probable crossovers. Of the total of 9 families reported to date 4 have had the genes for beta thalassaemia and Hb A2' in cis and 5 in trans. These findings are contrasted with the findings in families where a beta-chain structural variant and Hb A2' have been observed together and these genes have always been found in trans and never in cis. The reasons for linkage disequilibrium of this type are discussed. It is concluded tentatively that the distance between the delta-structural and beta-thalassaemia loci is greater than that between the delta-structural and beta-structural loci. To date this conclusion can only be applied to the beta+ -thalassaemia and beta-thalassaemia genes as found in the African population, since this is the only population with a high incidence of delta-chain mutants which allow linkage analysis of this type to be carried out.

A microchromatographic procedure (Isolab Fast Hb Test System) which was developed for the quantitation of Hb AI (10) has been found useful for the quantitation of Hb F in samples that contain Hb S and/or Hb C but no Hb A (% Fmicro). This method has been evaluated through analyses of known mixtures of Hb F and Hb S. The Hb Fmicro levels in patients with sickle cell anemia and related conditions were compared with results obtained by alkali denaturation (% FAD) and conventional DEAE-cellulose chromatography (% FDE). This microchromatographic technique is a fast, simple, and sensitive method for Hb F quantitation in patients with Sickle cell disease.

Summary. Red cell survival was estimated in a group of adult sickle cell anaemia patients using the 51Cr technique. Counts of irreversibly sickled cells were performed on thin coverslip preparations of capillary blood. These counts are relatively constant within the same individual but show marked variations between individuals. A significant correlation has been demonstrated between the irreversibly sickled cell count and the red cell survival. This correlation does not apply to sickle cell anaemia patients with splenomegaly in whom the irreversibly sickled cell count is always low.

Summary. The clinical and haematological features of 56 Jamaican patients with sickle-cell /β-thalassaemia (S/Thal) are reviewed. The two types of S/Thal (with and without Hb A) had distinctive haematological and clinical characteristics. In general, the non-Hb-A type had evidence of lower haemoglobin levels, a more rapid haemolytic rate, and a more severe clinical course than the Hb-A type.

Haemoglobin Constant Spring is an unusual variant which comprises only 1–2% of the total haemoglobin in heterozygotes. It has α-chains which are 172 residues long instead of the normal 141, and when it is inherited together with an α-thalassaemia gene it gives rise to haemoglobin H disease.

EDITORIAL SYNOPSIS The number of conditions which can result in intestinal malabsorption increases steadily. The one described by the authors in this paper follows infestation with Strongyloides stercoralis which is widespread in the tropics. Features suggesting the diagnosis in a patient with malabsorption are, according to the authors, persistent vomiting due to duodenal involvement and characteristic radiographs of the duodenum. The diagnosis is proven when the duodenal mucosa is examined and the lesion can be treated, when the symptoms will disappear.

A delayed hemolytic transfusion reaction precipitated by anti-Cob is described in a multiple transfused primigravida woman with sickle-cell disease. Sixteen days after the prophylactic transfusion of the first of 4 units of red cells, she experienced a fall in hemoglobin concentration accompanied by a newly positive antibody screen and direct antiglobulin test. Anti-Cob was identified both in the patient's serum and in an eluate prepared from her red cells.

The outcome of pregnancy has been analyzed in 72 women with sickle cell anemia (SS) and 26 women with sickle cell-hemoglobin C disease (SC), part of an unselected population of 148 women over 18 years of age with these hemoglobinopathies, who have been followed at a sickle cell disease clinic for 8 years. In SS women, 22% of first pregnancies were aborted spontaneously, and the overall early fetal loss was 19.2%. A similar figure was calculated from the literature since 1956. In SC women, 12% of first pregnancies were lost, but the overall early fetal loss was only 8.9%. The perinatal mortality, under quite variable conditions of prenatal care and delivery, was 10.2% in SS women and 2% in SC women. There were no stillbirths or midterm deaths in utero among SC women, but these accounted for most of the perinatal mortality in SS women, particularly in first and second pregnancies. There was one neonatal death in each group, but eight third pregnancies in SS women were completed without perinatal mortality. A remarkable finding among the SC women was the number of successful pregnancies, ten in one woman, and many of the pregnancies were completed without the supervision of a physician. Our findings were compared with those in the literature, and the conclusion that we drew is that termination of pregnancy and sterilization of young women are not generally indicated solely on the basis of these hemoglobinopathies.

We have examined the effect of 2, 3-diphosphoglycerate (DPG) on the solubility of deoxy-sickle hemoglobin (deoxy-Hb S) under conditions such that concentration, pH, and osmolarity of deoxy-Hb S solutions approached physiological. The range of DPG/Hb molar ratios encompassed the extremes found for this ratio in erythrocytes from individuals with sickle cell anemia. After monomer-polyer equilibrium had been established, the phases were separated by centrifugation and assayed for concentrations of Hb and DPG. DPG had no effect on the solubility of deoxy-Hb S. Furthermore, at DPG/Hb molar ratios less than one, there was no preferential incorporation of deoxy-Hb S containing bound DPG into polymers. At DPG/Hb molar ratios greater than one, concentrations of free DPG in monomer and polymer phases were virtually identical. Thus, under the specified equilibrium conditions, DPG is not a determining factor in the polymerization of deoxy-Hb S.

The syndrome thalassemia intermedia can be the clinical expression of heterozygosity for different tyes of thalassemia, beta-thalassemia and hereditary persistence of fetal hemoglobin, beta-thalassemia and Hb-Lepore, and in blacks it may even represent a true beta-thalassemia homozygote. This report describes thalassemia intermedia in a white male due to beta-thalassemia and an unstable hemoglobin. Chain-synthesis studies showed an excess of alpha-chain production over beta-chain production in the propositus and his mother but balanced chain synthesis in the clinically normal father, who is heterozygous for the unstable hemoglobin. The unstable hemoglobin was found to be beta14 (A11) Leu leads to Pro, which has previously been described in a clinically normal African woman, and named Hb-Saki. This hemoglobin is not distinguishable from Hb-A on routine electrophoresis at alkaline or acid pH and tests for unstable hemoglobins are necessary for its detection. The increasing list of such hemoglobin variants and previous cases of heterozygosity for beta-thalassemia and unstable hemoglobins are reviewed.

Hematuria is a rather frequent complication in patients with sickling disorders. However, the occurrence, incidence and management of this complication during pregnancy have not been discussed in the medical literature. We treated three patients with sickle-cell-induced hematuria in pregnancy and developed an approach we find useful for such patients.

Bone marrow infarction was investigated by 99mTc-sulfur colloid imaging in 42 patients with sickle cell anemia (SS) over a period of 2 yr. Marrow defects were demonstrated in 28 patients (66.6%), and in 15 (aged 19--52 yr), they were matched by roentgenographic evidence of medullary bone infarction. Repeated images showed no change in the size or site of these defects. Among 13 patients (aged 6--32 yr), all in crisis when initially examined, marrow defects were not associated with roentgenographic changes, and in many cases, repeated images showed resolution or decrease in size of the defects in 3--6 mo, even if the limb had been swollen and the marrow defect large. Among 14 patients (aged 18--36 yr), all asymptomatic at the time of study, no defects were found. Comparison of hematologic variables revealed a higher mean hemoglobin and hematocrit level among those with marrow infarcts (p less than 0.0001). High levels of HbF, or the presence of alpha-thalassemia, did not protect against marrow infarction. Pulmonary fat embolism was not observed. 99mTc-sulfur colloid marrow imaging was considered to provide more useful information in the initial management of bone pain and swelling in sickle cell crisis than either roentgenographs or conventional 99mTc-methyldiphosphate bone images.

Although there is as yet no definitive treatment for patients with sickle cell disease there has been considerable improvement in the overall management of these patients in recent years. This stems largely from a better understanding of the disease process. The risks from infection in infancy and childhood due to asplenia ae now well known, and children at risk ar being identified and treated. The role of platelets and the activation of clotting factors, while still controversial, are now acknowledged as appropriate areas for research. The judicious use of blood transfusions for cerebral infarction has improved the prognosis for this complication, as it has for pregnancy and the fetus. Blood transfusion, however, has its own hazards in sickle cell disease and the extent to which it can be used requires further investigation. Finally, the broad spectrum of hematological findings and individual clinical variations in sickle cell disease is now better understood.

Liver biopsy results and clinical records from 13 patients with sickle cell anemia were reviewed to assess the relative importance of local ischemia or of factors unrelated to sickling as a cause of their liver disease. Two of the biopsy specimens were normal and one showed cirrhosis. Nine patients had received multiple blood transfusions and nine had cholelithiasis, of whom two also had choledocholithiasis. Seven had both risk factors. Five had lobular cholestasis and four had acute or chronic hepatitis. One biopsy specimen showed changes of the Budd-Chiari syndrome. Another showed clear portal tract changes of large bile duct obstruction but no mechanical blockage of the biliary system; this suggests the thickened bile as postulated by Muirhead. Otherwise the changes observed were those to be expected in a heavily transfused population with a high prevalence of gallstones.

We examined 110 consecutive unselected patients with SS, SC, or Sthal sickle hemoglobinopathies to determine the prevalence of various retinal lesions within each group. The most prevalent retinal abnormality was the black sunburst, occurring in 46% of SS patients, 63% of SC patients, and 37% of Sthal patients. Our data also suggest that retinal lesions become more prevalent up to the fifth decade of life. Included in our series was an eight-year-old SS hemoglobin patient who presented with a dense vitreous hemorrhage secondary to a large salmon patch that had bled into the vitreous, reducing her vision to 20/200.

The thalassemias are a heterogeneous group of genetically determined disorders of hemoglobin synthesis and can be divided into alpha-thalassemias and beta-thalassemias. The genes for these disorders are carried as relatively harmless traits which can be detected in the laboratory by a series of tests. As there are several variant genes in each group, heterozygotes for two slightly different genes occur, and interaction of these thalassemia genes with the hemoglobinopathies is quite common. Severe clinical disease usually only occurs in homozygotes, as in Cooley's anemia. The problem for the laboratory is to distinguish thalassemia trait from other causes of microcytosis and hypochromia in an economical and efficient way. The various proposed schemes are discussed, and it is suggested that detection of these traits should be part of a comprehensive screening program for hemoglobinopathies and thalassemias.

The blood in sickle cell anemia has a very low oxygen affinity and, although 2,3-diphosphoglycerate (2,3-DPG) is increased, there is doubt as to whether this is the only factor responsible. In this study of 15 patients with sickle cell anemia (Hb SS) no correlation was found between oxygen affinity (P(50) at pH 7.13) and 2,3-DPG in fresh venous blood. Whole populations of Hb SS erythrocytes were therefore separated, by an ultracentrifuge technique, into fractions of varying density. The packed red cell column was divided into three fractions; a bottom fraction rich in deformed cells or irreversibly sickled cells (ISC), with a very high mean corpuscular hemoglobin concentration (MCHC); a middle fraction containing cells with the highest content of fetal hemoglobin; and a top fraction containing reticulocytes and discoid cells but free of deformed cells. Oxygen affinity was shifted to the right in all layers (mean P(50) (pH 7.13)+/-1SD: top 46.3+/-2.9 mm Hg: middle 49.8+/-4.9 mm Hg; bottom 61.0+/-5.8 mm Hg) compared with normal blood (top 32.1+/-0.7 mm Hg: bottom 30.1+/-0.5 mm Hg). 2.3-DPG was increased in the top fraction, but was low or normal in the bottom fraction (top 21.8+/-3.4 mumol/g Hb: middle 17.7+/-2.2 mumol/g Hb; bottom 13.8+/-3.1 mumol/g Hb; normal whole blood 14.3+/-1.2 mumol/g Hb). The level of 2,3-DPG in top fractions could not account for the degree of right shift of P(50), and in the middle and bottom fractions the even greater right shifts were associated with lower levels of 2,3-DPG. Top fraction cells depleted of 2,3-DPG had a higher, but still abnormally low, oxygen affinity. A strong relationship was found between oxygen affinity and MCHC. The fractions with the greatest right shift in P(50) had the highest MCHC (top 32.4+/-2.0; middle 36.2+/-3.1; bottom 44.6+/-3.2 g/100 ml, respectively) and the plot of P(50) vs. MCHC showed a positive correlation (r = 0.90, P < 0.001). The red cell population in sickle cell anemia is not homogeneous but contains cells of widely varying Hb F content, 2,3-DPG, and hemoglobin concentration. Paradoxically, the cells with the lowest O(2) affinity have the lowest 2,3-DPG, but they also have the highest concentration of Hb S. The dense, deformed cell called the ISC is but the end stage in a process of membrane loss and consequent increase in hemoglobin concentration. The P(50) of Hb SS blood is, to a large extent, determined by the presence of these cells (r = 0.85, P < 0.001). Increased concentration of Hb S in the cell favors deoxygenation and crystallization even at relatively high P(o2). Lowered affinity for oxygen appears to be closely associated with Hb S concentration and not with 2,3-DPG content.

Summary The movements of iron-dextran, following a total dose infusion of up to 2550 mg. iron in six severely iron deficient patients, have been studied using a 59Fe tagged complex. The preparation is removed from the plasma in 8–10 days. Fifty per cent of the iron was incorporated into haemoglobin in 3–4 weeks and the iron stores replenished rapidly. Using organ scanning, the liver was confirmed as the site of primary plasma clearance, but accumulations of iron were also detected in the spleen and bone marrow. Only minute quantities of radioactivity appeared in the urine. No untoward effects on iron metabolism have been detected, but reduction of the serum iron and total iron binding capacity to low levels 6 weeks post infusion is of interest. An attempt has been made to interpret the findings to elucidate the ferrokinetics of this method of treatment.

Methods adopted in a routine bacteriology laboratory for the rapid identification of Enterobacteriaceae isolated from urine are described. The incidence of various bacteria causing infection in paraplegics after catheterization of the bladder is recorded, Klebsiella accounting for the majority of infections caused by lactose fermenters and Providence for the majority of `paracolon' infections. The importance of these bacteria in cross-infection is discussed.