Paul F. A Milner

The Irreversibly Sickled Cell; a Determinant of Haemolysis in Sickle Cell Anaemia

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.

HÆMOGLOBIN-H DISEASE DUE TO A UNIQUE HÆMOGLOBIN VARIANT WITH AN ELONGATED α-CHAIN

Abstract The clinical and genetic properties of an unusual α-chain variant of human hœmoglobin are described. It constitutes less than 1% of the total haemoglobin in heterozygotes and, when inherited together with an α-thalassaemia gene, produces the clinical picture of haemoglobin-H disease. Preliminary structural studies indicate that, in addition to the 141 aminoacid residues which constitute the normal α-chain, this variant has about 31 extra residues attached to the C-terminal end.

The metabolism of iron-dextran given as a total-dose infusion to iron deficient Jamaican subjects

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.

The Clinical Features of Sickle-Cell/β Thalassaemia in Jamaica

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.

Absorption of iron from maize ( Zea mays L.) and soya beans ( Glycine hispida Max.) in Jamaican infants

1. The absorption of iron from 59 Fe-labelled maize and soya-bean preparations was measured by whole-body counting in forty-two apparently healthy Jamaican infants and compared with the absorption of ferrous ascorbate. 2. The mean absorption of Fe from maize was 4·3% and from soya beans baked at 300°, 9·4%, compared with 28·5% for ferrous ascorbate. In a group of children given boiled soya beans the mean absorption of Fe was 2·8%, and of ferrous ascorbate 16·7%. 3. There was much variability between replicate tests made on the same child at intervals of 1–2 weeks. 4. The absorption of food Fe was not increased in children who were considered to be anaemic (haemoglobin less than 100 g/l) or Fe-deficient (serum Fe less than 500 μg/l and saturation of total Fe-binding capacity less than 15%). 5. The poor availability of Fe in maize meal, which is a staple food of children in Jamaica, is probably an important cause of the high prevalence of Fe-deficiency anaemia.

Haemoglobin concentration, eosinophilia and intestinal helminths in children in rural Jamaica.

Abstract Investigations on haemoglobin and haematocrit values, eosinophils and faecal helminth eggs in rural Jamaican infants and children are summarized. Haemoglobin levels rose from 10·6 g.% at about the fifth month of life to 10·9 g.% at one year and thereafter climbed slowly to 12·2 g.% at 6 years and remained at this level to 15 years. Values for haematocrit and MCHC behaved similarly. The mean haemoglobin levels were about 1·0 g.% below optimal values but about 2·0 g.% above those reported from Gambia. Severe anaemia was rare but minor degrees of iron deficiency and, in the first year of life, of folic acid deficiency, may be common. 2 cases of sickle-cell anaemia and one of thalassaemia major were seen. Neither malaria, which has been eradicated, nor hookworm is now an important cause of anaemia in Jamaica. Helminth eggs in stools were not common in the first and second years but were present in 60% of children in the third and fourth years. Ascaris lumbricoides was the most prevalent, giving rise to the heaviest concentration of eggs, followed by Trichuris trichiura . A few hookworm eggs were found in about 10% of children over 2 years. In one study involving 160 children aged about 3 years, no relationship was found between helminth eggs and haemoglobin levels, heights, weights or symptoms which might be related to infection. Helminthiasis, although extremely common, does not appear to be a major cause of ill-health or of failure to thrive among Jamaican children. Eosinophils were numerous in the latter half of the second year of life and by 5 years, on average, comprised 13·5% of all white cells. Although an aetiology other than intestinal helminthiasis is not obvious, a correlation between eosinophils and faecal helminth eggs could not be demonstrated. Some children may have been infected with Toxocara canis .

Pregnancy and homozygous haemoglobin C disease

OVER the past few years, there have been many reports on the maternal hazards in the more common haemoglobinopathies, sickle cell anaemia and haemoglobin SC disease. Although Terry et al. (1954), Movitt et al. (1964), and Watson-Williams and Wetherall (1 965), all mention the homozygous haemoglobin-C state occurring in a few pregnant or parous women, there have been no reports dealing specifically with the course of pregnancy in the presence of this haemoglobinopathy. The heterozygous haemoglobin C trait occurs in 2.56 per cent of Jamaicans, but the homozygous form is rare, with an expected frequency of 1 in 5,000 (Miall et al., 1967). Terry et al. (1954) quoted an incidence of 0.017 per cent in a Negro population: Went (1957) found no cases in an antenatal survey of 1,018 patients in Jamaica; St. J. Brew and Edington (1965) detected 0.2 per cent incidence of haemoglobin CC by electrophoresis in 2,435 postmortem examinations in Nigeria; and Watson-Williams and Wetherall (1965) found an incidence of 0.24 per cent in Yoruba adult blood donors screened in the same area. In contrast to some of the other haemoglobinopathies, the homozygous C state is mild in effect. There is slight shortening of the red cell survival (Wheby et al., 1956; Motulsky, 1965). There is a well compensated haemolytic process with a normochromic microcytic anaemia, many target cells and occasional normoblasts. There may be a slight increase in the reticulocyte count and serum bilirubin, and there is decreased osmotic fragility. Clinical manifestations are few -splenomegaly and arthralgia are common, and there may be abdominal pain (Smith and Krevans, 1959); but the abdominal crises of sickle cell anaemia do not occur. Cholelithiasis is said to be common. The most likely clinical presentation of this haemoglobinopathy is therefore an obscure arthralgia associated with splenomegaly .