Incidence of haemolytic disease of the newborn in Harare, Zimbabwe.

BACKGROUND: Haemolytic Disease of Newborn is responsible for a number of neonatal deaths and complications worldwide. Its incidence in Zimbabwe is not clearly understood. OBJECTIVE: To find out incidence of Haemolytic Disease of Newborn in Harare and ability to identify antibodies associated with HDN. METHODS: A retrospective cross sectional study at the Parirenyatwa Group of Hospitals and National Blood Service, Zimbabwe (NBSZ). We studied 22493 infants at Parirenyatwa Hospital during the 1995-1997 and 2002-2003 periods. The main outcome measures were ABO and Rh blood group results, Direct Antiglobulin Test and Maternal Antibody Screening and Identification Results were obtained from the NBSZ. RESULTS: One hundred and ninety-one (0.85%) infants had Haemolytic Disease of Newborn. One hundred and sixty-three (85.34%) of these were due to anti-AB, twenty five (13.09%) were due to anti-D and three (1.57%) due to anti-Kell. Incidence of Haemolytic Disease of Newborn during 1995-1997 and 2002-2003, were 0.93% and 0.64%, respectively (p = 0.014). ABO Haemolytic Disease of Newborn showed a statistically significant difference during the two periods (p = 0.003). Rhesus Haemolytic Disease of Newborn showed no statistically significant difference during same periods (p = 0.317). CONCLUSION: The incidence of Haemolytic Disease of Newborn at Parirenyatwa Hospital is comparable with that found in other countries. It is recommended that K antigen be included in the pretransfusion testing to avoid anti-K related Haemolytic Disease of Newborn.

Demographic and social characteristics of regular donors who sero-converted in Harare.

Zimbabwe, like any other country, is currently experiencing a fast growing HIV/AIDS pandemic. A considerable number of infections are caused by blood transfusion. The aim of this study is to determine risk factors, events and socio-demographic characteristics associated with incidence of HIV infections and to prevent sero-conversion of regular blood donor. A retrospective cross sectional study was done. 22,922 regular donors at National Blood Transfusion Services in Harare were used. The number of all regular donors who sero-converted and their status during the 1999 to 2001 period were determined. About 327 (1.4%) of the regular donors sero-converted. Two hundred and seventy-four (84%) were males and 53(16%) were females. 52.6% of the males were married, 46.7% were single and .7% separated. 30.2% of the females were married, single women 67.9% and separated women 1.9%. Increased sero-conversion was associated with unemployment, high-density area residence and the sexually active age group (21 to 45 year olds). There was an association between gender and marital status among sero-converters (c2 = 8.48; P-value = 0.014) and males were likely to be older than females (t = 2.9; P-value = 0.0019). It can be concluded that unemployment and living in high-density residential areas are highly associated with HIV sero-conversion among regular donors. Single females, working class males and the sexually active age group are highly exposed to risk factors. It is recommended that donor education schemes and knowledge of these factors should be considered during donor recruitment.

Prevalence of HIV infection in school based and other young donors during the 2002 and 2003 period.

The majority of donor blood in Zimbabwe comes from school-based donors. Zimbabwe has one of the highest HIV prevalences in the world and the age at which the infection is acquired is decreasing. This is a serious threat to the safety of blood supply. The prevalence of HIV has been low among the youth the majority of whom are still going to school and between the ages of sixteen and nineteen years. However, due to the changing socio-economic environment, sexual behavioural patterns have also changed. It is now necessary to evaluate these changes in order to guarantee safe blood transfusion. To determine the prevalence of HIV among adolescent donors during the period between 2002 and 2003. Cross-sectional retrospective study, National Blood Transfusion Service (NBTS). All school based donors and others between 16 and 19 years of age. The number of donors who were HIV positive in this age group. Data on donors was collected from computer files at the National Blood Transfusion Service (NBTS) Information Technology (IT) department. Prevalence of HIV was determined and categorised according to gender, age and the type of school the donor attended. The prevalence of HIV in 2002 and 2003 were 0.48% and 0.38%, respectively. Sixty-six per cent (66%) of HIV positive donors had donated for the first time. The prevalence in both periods was much higher in female donors than male donors. In 2002 males and females had prevalence of 0.28% and 0.66%, respectively. In 2003 males and females had prevalence of 0.18% and 0.55%, respectively. The overall highest prevalence (0.90%) was found between the 16-19 year age group who were not going to school (others). In 2002 female day schools had the highest (0.87%). The lowest prevalence (0%) was found in male boarding schools. In 2003 the highest prevalence (1.61%) was found in the 16-19 year age group who were not going to school (others). The lowest prevalence (0) in the same year was found in male boarding scholars. It can be concluded that the majority of HIV positive school based donors are first time donors. Female scholars and those of the same age group who are not going to school have the highest risk of donating HIV positive blood than male donors. The prevalence of HIV in adolescent blood donors decreased with age. It is recommended that active donor recruitment should be in favour of the low prevalence groups.

Haematology reference values for healthy elderly blacks residing in Harare, Zimbabwe.

OBJECTIVES: To determine reference values for elderly blacks and to compare them to those in use in local hospitals and in other countries in the region. DESIGN: Cross sectional study. SETTING: Sekuru Kaguvi Hospital, Harare, Zimbabwe. SUBJECTS: 151 persons of age 45 years or more. MAIN OUTCOMES MEASURES: Haematological parameters investigated were Hb, Hct, MCV, MCH, MCHC, Plt, RBC and WBC. RESULTS: 56 males and 95 females tok part in the study. RBC, Hb and Hct mean values were significantly higher (p=0.004, p<0.001 and p<0.001, respectively) in males than in females. However, no significant differences between sexes were found in WBC (p=0.137), MCHC (p=0.273), MCV (p=0.090) and MCH (p=0.074). Platelet counts were significantly higher (p=0.040) in females [median (Q1, Q3): 251 (117, 478)] than in males, 226 (122, 251). These haematogological vales were notably different compared with those in current use in local hospitals. The mean values obtained for each index were comparable with those obtanied in other countries in the same region (Southern Africa) as Harare. The reference values for the elderly blacks are presented. CONCLUSION: The importance of gender and population specific reference values cannot be over emphasised. The reference values obtained in the current study should be appropriate for evaluating haematological test results in elderly blacks in Zimbabwe.

Use of packed red cells in a major hospital in Harare, Zimbabwe.

OBJECTIVES: To document the current pattern of packed red cell (PC) usage and the crossmatch to transfusion ratio (C/T ratio) in a major city teaching hospital in Harare, Zimbabwe. DESIGN: Restropective, (audit). SETTING: Harare Central Hospital, a 1,200 bed multidisciplinary hospital located in Harare, Zimbabwe. MAIN OUTCOME MEASURES: Amount of PC ordered and proportion collected for the year 1995. Quantity of PC used by different medical specialties. RESULTS: In 1995 a total of 8,292 PC were collected from Harare Hospital blood bank. This translates to an average PC usage for a 1,200 bed hospital of seven units per hospital bed per year. Only 48.5% of PC crossmatched was collected with a C/T ratio of 2.1:1. Revenue loss of Z$478,434 is estimated to have occurred due to expired units and resource wastage from uncollected crossmatched units. The largest consumer of PC was the Department of Gynaecology, followed by Surgery and Paediatrics. CONCLUSION: Regular auditing of blood usage is recommended to promote the efficient use of PC in accordance with accepted international standards and local guidelines and practice.

A three-year prospective study of 137 cases of acute leukaemia in Zimbabwe.

We studied 137 cases of acute leukaemia seen between December 1985 and November 1988, using traditional staining techniques together with cytochemistry and in cases of probable acute lymphoblastic leukaemia (Sudan Black negative) by immunophenotyping. Not all tests were carried out in every case (some cases of ALL could only be classified as T or non-T). Paediatric group (age less than or equal to 14 yrs): 75 cases--acute lymphoblastic leukaemia 52, acute myeloid leukaemia 18, acute undifferentiated leukaemia 5. Peak incidence in 5-9 year group. Male:Female ratio = 1.7:1. acute myeloid leukaemia was associated with chloromas in 2 cases (11 pc). Adult group: 62 cases--acute lymphoblastic leukaemia 23, acute myeloid leukaemia 36 and acute undifferentiated leukaemia 3. Peak incidence in 50-54 age group. Male:Female ratio = 1:1.2. Acute lymphoblastic leukaemia subtypes (all ages) T 16, Common 20, Null 12, 'non-T' 16, B cell 0, untyped 11. 69 pc were of L2 morphology. In T-ALL, 11 had thymomas and Male:Female ratio = 15:1. Male:Female ratio for 'non-T' = 1.5:1. Acute myeloid leukaemia subtypes (all ages) M1 3, M2 8, M3 14, M4 19, M5 8, M6 2, M7 1. Overall incidence of acute leukaemia appears increased at 0.91 per 100,000 per annum from previous studies in Zimbabwe. Common ALL (mean age = 13 years) is an emerging problem and now outnumbers T-ALL (mean age = 10 years). This may be related to a general improvement in living standards and health in Zimbabwe.

Megaloblastic anaemia in Zimbabwe. 1: Seasonal variation.

Two hundred and ten patients who were confirmed to have megaloblastic anemia over a 2-year period were grouped according to the month of diagnosis. A distinct seasonal variation was detectable in the occurrence of megaloblastic anemia with a high prevalence in the wet season and a low prevalence in the dry season. The major factor postulated to be responsible for the seasonal fluctuations of the disorder is the concomitant diminution in the availability of folate-rich green vegetables; and not malaria transmission. As the dry season sets in and progresses, the frequency of megaloblastic anaemia cases increases reaching a peak during the wet season. It is suggested that an adequate supply of green vegetables like lettuce, spinach and cabbage throughout the year might lessen or even eliminate the seasonal variation of megaloblastic anaemia presently observed in this community.