Beta-globin gene cluster haplotypes and alpha-thalassemia in sickle cell disease patients from Trinidad.

In this study, we have determined the frequency of beta(S) haplotypes in 163 sickle cell disease patients from Trinidad. The alpha(3.7) globin gene deletion status was also studied with an observed gene frequency of 0.17. Among the 283 beta(S) chromosomes analyzed, the Benin haplotype was the most prevalent (61.8%) followed by Bantu (17.3%), Senegal (8.5%), Cameroon (3.5%), and Arab-Indian (3.2%), while 5.7% of them were atypical. This beta(S) haplotypes distribution differed from those previously described in other Caribbean islands (Jamaica, Guadeloupe, and Cuba), in agreement with the known involvement of the major colonial powers (Spain, France, and Great Britain) in the slave trade in Trinidad and documented an Indian origin of the beta(S) gene.

Severe aplastic anaemia - complete response to antilymphocyte globulin and cyclosporin

Severe aplastic anaemia is uniformly fatal unless treated with immunosuppressive therapy or bone marrow transplantation. The latter is curative in 65 percent of patients and is the treatment of choice in children and young adults. Antilymphocyte globulin (ALG) and cyclosporin may be used successfully in the absence of an HLA matched sibling donor. We report the case of a twelve year old boy with severe aplastic anaemia who received immunosuppressive with ALG and cyclosporin and is alive and well three years an six months post treatment.(AU)

Fatal metastatic calcification in a patient with HTLV-I-associated lymphoma

Metastic calcification of the heart, lungs and kidneys is described in a 42-year-old male who had an HTLV-I-associated lymphoma. This fatal complication of HTLV-I-associated lymphoma has been infrequently reported, and the case in question is the first to be recorded in the Caribbean, where HTLV-I is common. Aggressive therapy of hypercalcaemia should be instituted early in its genesis in these lymphomas, so as to avoid its fatal outcome (AU)

Screening for HTLV-I in healthy blood donors in Trinidad and Tobago, West Indies

Of 1089 healthy blood donors screened for HTLV-I using ABBOTTS HTLV-I EIA: 18 (1.7 percent) were positive; and 16 (1.5 percent) were confirmed positive using HTLV-I/11 Cambridge Biothec Western Blot method. HTLV-I antibodies were found amongst the major ethnic groups, viz. Africans, 11 cases (68.75 percent) and East Indians 4 cases (25 percent). The mean age of the donors who tested positive for HTLV-I was 30.75 years; and the male to female ratio was 4.3:1. (AU)

A common HLA haplotype in leukaemic families in Trinidad - abstract

In a previous study, 6 of 10 patients with acute lymphoblastic ;leukaemia (ALL) were found to have the HLA-B40 antigen, 4 of these 6 patients carrying both the HLA-A2 and B40 antigens. Three of these 4 patients have since died. In the present study, family studies were performed in order to determine whether the HLA-A2 and B40 antigens constituted a haplotype in these individuals. Of the 4 families, 3 were available for HLA typing. Results show that HLA-A2/B40 did constitute a haplotype in all three families. Furthermore, the haplotype in all cases was found to be of maternal origin. Whether this haplotype is associated with an immune response gene which conveys susceptibility of the disease cannot be determined from this small study. Further typing of leukaemic children and their families (including DR antigens) should be pursued. These findings may be found to have prognostic implications for treatment, since patients with the HLA-A2/B40 and A2/B12 haplotypes have been shown to have improved long-term survival with transfer factor immunotherapy in other populations (AU)

Characteristics of HIV-Positive blood donors in Trinidad and Tobago - abstract

This study was undertaken to better understand HIV-positive donors in order to improve the safety of donor blood supply in Trinidad and Tobago. A total of 45 HIV-positive blood donors were identified for the years 1986, 1988 and 1989 and letters (1 initially and 2 follow up) were sent to all. Non-responders (the majority) were traced to their home or place of work and written consent sought from those who were located. A questionnaire covering demographics, history of blood donation, risk factors for and knowledge of AIDS and quality of care. Subjects were counselled about AIDS and were given material about HIV and safe-sex practices. The whereabouts of 35 were traced, 3 had died and 26 persons consented to participate in the study. Seropositive donors were predominantly young males (23/26) and there was a ratio of 18:1 of Negroes to East Indians. Declared sexual preferences were heterosexual (16), bisexual (6) and homosexual (1). Half of the respondents had only completed a primary school education. The participants had a good knowledge of AIDS, its aetiology, mode of transmission and persons at highest risk, etc. Overall, 18 of the 26 seropositive donors reported independent risk factors (homosexually/bisexuality, genital ulcerative disease, prostitution, cocaine). As a result of this study, the reported seroprevalence rate from Trinidad and Tobago could be adjusted to 0.15 percent compared with 1.1 percent which was previously reported (AU)

A family with homozygous haemoglobin E in Trinidad and Tobago

We report the first case of homozygous E in the West Indies, and describe the family, whose ancestors came to Trinidad from India approximately 100 years ago (AU)

Fanconi's aplastic anaemia in two sisters in Trinidad and Tobago

This report describes two cases of Fanconi's anaemia in Trinidadian sisters of East Indian origin. The cases have been confirmed by chromosomal analysis which showed increased breaks and ring forms. Anorexia was a persistent finding in both cases. One of the sisters also had a poor growth hormone response. (AU)

Immunological surface marker and histocompatibility antigens in childhood acute Lymphoblastic leukaemia in Trinidad - abstract

Between October, 1983 and May, 1986, seventeen cases of childhood acute lymphoblastic leukaemia (ALL) were diagnosed on clinical grounds, supported by the findings of blast cells in the blood film or the bone marrow aspirate. All the patients had more than 25 percent blast cells in the bone marrow. Patients were described as belonging to a particular ethnic group when all four grandparents belonged to that group. Typing for lymphocyte surface markers was done at the time of the initial diagnosis. Fifteen of seventeen cases were under 10 years of age. Boys outnumbered girls by almost 5:1 Ten of the seventeen patients were of East Indian origin; five were of mixed ethnicity, with three of these having at least one grandparent of East Indian origin. Seven of the patients under ten years of age presented with bone and/or joint pains. Nine of the seventeen ALL patients were successfully phenotyped for immunological surface markers. Six of these carried T-cell markers. Four of the six T-cell clones were thymocytes (three stage III and one stage I). Three patients were common ALL antigen-positive (CALLA+) but these also had markers suggestive of a pre-B phenotype (OK-, OKB2+, CALLA+ and OKT-10+). HLA tissue typing of ten of the patients showed an enhanced frequency of th HLA B-40 antigen when compared with controls (p<.0001). This antigen was present in 60 percent of the patients typed, 40 percent of whom carried the HLA A2/B40 halotype. None of the cases carried the HLA B-5 antigen although this antigen had a frequency of 19 percent in the control group (p<0.05). The antigen A-11 showed a decreased frequency (10 percent percent in patients compared with controls (13.3 percent), while B-15 showed an increased frequency (15.0 percent) compared with the control group (4.0 percent), but these differences were not statistically significant. Childhood leukaemia in Trinidad is primarily a disease of East Indian children. Bone or joint pain seems to be a common presenting feature and the common ALL antigen type of leukaemia is less common than T-cell leukaemia, Current evidence would suggest a linkage diequilibrium between HLA B-40 and childhood ALL in Trinidad (AU)

Neonatal jaundice at Port-of-Spain General Hospital - abstract

Neonatal jaundice is a major cause of morbidity in developing countries. The preventions of kernicterus is one of the goals of paediatricians in these countries. In an attempt to elucidate the aetiology of neonatal jaundice in our population, a prospective study was done at the Port-of Spain General Hospital from 15th June, 1986 to 30th September, 1986. Ninety-five patients were enrolled; 63 percent of the sample were of African descent, 19 percent of East Indian descent and 11 percent of mixed race. Forty-four per cent had ABO incompatibility, and 44 percent had no blood incompatibility, of which 26 percent were glucose-6-phosphate dehydrogenase (G6PD) deficient. G6PD deficiency was found in 21 percent of the total sample. In 33 percent of the sample, the aetiology is unknown. Moderate/severe jaundice (bilirubin > 16 mg/100 ml) was seen in 58 percent of the ABO incompatible group, 55 percent of the "unknown" group, 43 percent of the Rh incompatible group and 75 percent of the G6PD-deficient group. Most of the ABO incompatibility and Rh incompatibility cases (92 percent and 85 percent) developed jaundice within 48 hours of birth. In contrast, only 55 percent of the G6PD-deficient group and 50 percent of the "unknown' group developed jaundice early. Camphor was used by 60 percent of the G6PD-deficient group, 35 percent of the ABO incompatible group and 39 percent of the "unknown" group. Since 1984, there has been an active policy at the Port-of-Spain General Hospital which ensures that all children with ABO incompatibility are observed for forty-eight hours for the development of jaundice. It is recommended that a screening policy for G6PD deficiency should be adopted, since it is an important cause of jaundice in the children, presents later and can cause moderate/severe jaundice. Camphor use should be discouraged since it is a known precipitant of haemolysis in G6PD-deficient individuals (AU)

The epidemiology of HTLV-I and HTLV-III associated diseases in Trinidad and Tobago - abstract

Clinical studies in Trinidad and Tobago have shown that, between May 1982 and June 1985, 24 cases of adult T-cell lymphoma/leukemia (ATL) were seen at the Port-of-Spain General Hospital. The clinical features were very similar to those reported from Japan and Jamaica. The male/female ratio was 14/10. A random survey of antibodies to HTLV-I (Elissa assay) was carried out in Trinidad and Tobago in people aged 20 years and over. In Trinidad, of 1,578 people sampled, 51 (3.3 percent) were positive. Forty-one out of 794 Trinidadians of African descent were positive (5.1 percent) while only 3 of 448 Trinidadians of Indian descent were positive (0.7 percent). In Tobago, 18 out of 151 Tobagonians were antibody positive (12.0 percent). All were Tobagonians of African descent. There were no Tobagonians of Indian descent in this survey. The first case of the Acquired Immune Deficiency Syndrome (AIDS) was diagnosed in Trinidad in February 1983, and, up to November 1985, 50 cases of this disease have been diagnosed at the Port-of-Spain General Hospital. A random survey of antibodies to HTLV-III in the general population of Trinidad showed that out of 1,578 Trinidadians studied only 6 (0.4 percent) were antibody positive. Of 151 Tobagonians, 3 were positive (1.5 percent). All positive results were confirmed by Western blotting. On the other hand, in a survey of 105 healthy homosexuals in Trinidad, 40 percent were shown to be positive for HTLV-III antibodies. Thirty-six of 81 homosexuals of African origin were antibody positive (44.4 percent) while 6 out of 16 homosexuals of Indian descent were positive (37.5 percent). All the clinical cases of ATL occurred in Trinidadians of African descent and apart from one child aged 18 months of Asian descent, all the patients with AIDS were people of African origin. These epidemiological findings suggest that a genetic factor may be proved necessary for the development of HTLV-associated diseases in Trinidad and Tobago (AU)

Incidence of haemoglobinopathies in the newborn in Trinidad and Tobago - abstract

A prospective study of 1,254 cord blood samples was carried out from the 9th July to 10th August, 1984 at the Maternity Units of the Mount Hope, Port-of-Spain, San Fernando and Scarborough Hospitals. Electrophoresis on cellulose acetate and citrate agar was performed on 1,233 and 355 of the specimens respectively. Haemoglobins A, F, S and C and Bart's, separate on cellulose acetate, while citrate agar electrophoresis enables separation of haemoglobins S from D/O and C from E. Red blood cell indices were determined on 1,192 samples on the Coulter-S counter. HbA2 levels were not available to distinguish O-thallassaemia and á-thallassawmia. The overall incidence of haemoglobinopathy was 15.7 percent Hgb S was found in 9.9 percent of Negroes and 1.0 percent of Indians; Hgb C in 3.1 percent of Negroes and 0.7 percent of Indians; Hgb E was found in 0.2 percent and 0.4 percent of Negroes and Indians respectively. A minimal estimate for the incidence of O-thalassaemia in Negroes was found to be 3.1 percent with 2.2 percent in Indians. á-thalassaemia probably affects approximately 4.2 percent of Indians, and 2.9 percent of Negroes. There were significant differences in gene frequencies among the ethnic groups. Hence a significant number of babies are born each year with pathologically important haemoglobin disorders and thalassemia syndromes. The prevalence of these disorders does not reflect the annual birth rate of these haemoglobinopathies and hence suggests that many of the affected infants succumb to complications early in childhood. It would seem probable that the haemoglobino

Racial and other characteristics of human T cell leukemia/lymphome (HTLV-1) and AIDS (HTLV-111) in Trinidad

Adult T cell leukaemia/lymphoma was first recognised as a clinical entity in southwest Japan. Subsequently the Caribbean has been found to be another area where the disease is endemic, and sporadic cases have been identified in different parts of the world. The human T cell leukaemia/lymphoma virus (HTLV-1) is causally related to adult T cell leukaemia/lymphoma. A sub-group of HTLV, designated HTLV-111, has recently been isolated from many patients with the acquired immunodeficiency syndrome (AIDS) and preAIDS, and there is now evidence that this variant is the primary cause of AIDS. This is the first report from Trinidad to describe twelve cases of adult T cell leukaemia/lymphoma and 14 of AIDS. All were in patients of African descent. No cases were seen in subjects of East Indian descent, who, like those of African descent, comprise as much as 40 percent of the population

Immunization status of thirty patients with Sickle Cell disease five years post Hepatitis B vaccination: a comparison with normal controls

In order for hepatitis B immunization programmes to be cost effective and clinically beneficial, vaccinated persons should maintain an immunity threshold titre of antibodies to hepatitis B surface antigen greater than 10 IU/L. Those who fall below this level should be boosted in order to be covered against the risk for which the vaccine was administered. Persons with sickle cell disease are included in the group for whom hepatitis B immunization is routinely prescribed. Antibody to hepatitis B surface antigen was measured in paired sera of thirty patients with sickle cell disease compared with a control group of healthy medical staff, five years post vaccination. There was no significant difference between patients with sickle cell disease and normal controls in the levels of antibody maintained or numbers that required booster vaccination. Recommendations for the maintanance of protection via revaccination should be the same for persons with sickle cell disease as for healthy persons. (AU)