[1] Groote Schuur Hosp, Div Haematol, Natl Hlth Lab Serv NHLS, Anzio Rd, ZA-7925 Cape Town, South Africa
[2] Univ Cape Town, Anzio Rd, ZA-7925 Cape Town, South Africa
[3] Red Cross War Mem Childrens Hosp, Dept Paediat & Child Hlth, Haematol Oncol Serv, Cape Town, South Africa
[4] Red Cross War Mem Childrens Hosp, Div Anat Pathol, Natl Hlth Lab Serv NHLS, Cape Town, South Africa