Platelet Yield and Some Donor-Related Predictors in a Single Donor Apheresis: Report from a Nigerian Tertiary Hospital

BACKGROUND

Single-donor platelet transfusion is the preferred therapeutic option for patients with platelet insufficiency and its effectiveness is partly dependent on the yield.

AIM

To determine the platelet yield and predictors of platelet yield in single-donor apheresis.

MATERIALS AND METHODS

This was a five-year review of the data on single-donor apheresis using the Haemonetics Apheresis machine MCS+ at Alex Ekwueme Federal University Teaching Hospital Abakaliki Ebonyi state. Platelet donor related variable of interest included the pre-donation platelet count, donor's blood group, number of apheresis cycles and yield volume. Analysis was done using Graphpad Prism version 9.1.1.

RESULTS

A total of 153 platelet apheresis were studied. The mean (SD) values for pre-donation platelet count, number of cycles, platelet yield and volume of platelet concentrate were 279 ± 47 x 109/L, 6 ± 0.3, 4.5± 0.8 X 10 11/L, and 320 ± 78 mL respectively. In this study, volume of platelet concentrate predicted 61% of platelet yield while platelet count of donor predicted 41%. Neither ABO nor Rh blood groups was a determinant of platelet yield.

CONCLUSION

Pre-donation platelet count and volume of platelet concentrate are important predictors of platelet yield. There is need for proper platelet donor selection.

Prevalence of venous thromboembolism and its associations in a large racially homogenous population of sickle cell disease patients

To determine the prevalence of venous thromboembolism (VTE) among adult sickle cell disease (SCD) patients in Nigeria.

METHODS

This was a multicentre retrospective study in which the medical records of adult SCD patients were reviewed. Information on demographics, steady-state haemogram, clinical phenotypes, duration of follow-up, history of VTE including risk factors and management was collected.

RESULTS

Of the 509 SCD patients with a median (IQR) duration of follow-up of 2 years, 10 (2.0%) had VTE (9 DVT and 1 PE). Their median (IQR) age was 27 (22.8-30.3) years. Identifiable risk factors for VTE included positive family history (2, 20%) surgery, splenectomy, paraplegia and cancer (1, 10% each). No risk factor was identifiable in four persons. VTE had no significant association with age and gender. VTE was significantly associated with the following events: acute chest syndrome [p = .002, odds ratio (OR) 8, 95% CI 2.2-28.9], osteonecrosis [p = .012, OR 5.24, 95% CI, 1.45-18.91] and vaso-occlusive crisis [p = .035]. Also significantly associated with VTE were pulmonary hypertension [p = .001, OR 23.3, 95%CI 5.18-105.06] and stroke [p = .032, OR 9.35, 95%CI 0.87-53.25].

CONCLUSION

The prevalence of VTE among SCD patients in Nigeria is low. It is significantly associated with vaso-occlusive crisis, pulmonary hypertension and stroke.

Chronic Myeloid Leukaemia with Sudden Bilateral Deafness and Leg Ulcer Associated with Hydroxyurea Therapy

Deafness occurs rarely in patients with chronic myeloid leukaemia. Hydroxyurea-induced leg ulcer has been found in patients on long-term hydroxyurea therapy. We present a 53 year old man who developed spontaneous bilateral deafness shortly after he was diagnosed with chronic myeloid leukaemia and subsequently developed hydroxyurea induced leg ulcer in the course of treatment. A 53 year-old male presented to our clinic with six months history of left abdominal mass, associated with easy satiety, occasional fever, night sweats, loss of appetite, weight loss, easy fatiguability and bilateral leg swelling. Physical examination showed a middle-aged man in no obvious distress, afebrile, anicteric, pale, with no peripheral lympadenopathy but had bilateral pitting pedal edema to the lower third. There was no significant finding on the chest. Abdominal examination showed hepatosplenomagaly. Full blood count showed anaemia, hyperleucocytosis and thrombocytosis. Peripheral blood film and bone marrow aspiration examinations were in keeping with chronic myeloid leukaemia. The BCR/ABL-1 transcript was negative, thus he was started on hydroxyurea in addition to other supportive treatment. Before commencement of hydroxyurea therapy, he spontaneously developed bilateral sensorineural deafness. Subsequently, he also developed leg ulcers, having been on hydroxyurea therapy for seven years which healed within eight weeks on discontinuation of hydroxyurea. Spontaneous deafness can occur in patients with chronic myeloid leukaemia due to hyperleucocytosis and urgent cytoreduction may help to prevent this complication. In addition, leg ulcer due to long-term hydroxyurea therapy can occur and usually do not respond to the conventional treatment but discontinuation of hydroxyurea.