Erythrocyte phenotype in a pregnant woman of Sri Lanka. Description of the case and complications related to communication problems.

BACKGROUND: The Bombay phenotype is a rare genetic trait which is characterized by the absence of A, B and H antigens on red cells as well as in body secretions. The serum shows the presence of antibodies against antigen H. Patients with this rare blood type are not easily transfusable. We had observed a woman aged 18, at the 20th week of pregnancy, native of Sri Lanka, with an IgG and IgM class anti-H. We report the case and the clinical issues arisen. MATERIALS AND METHODS: The determination of ABO, Rh[D] group, the indirect antiglobulin test (IAT) were performed in tube techniques and in neutral gel microcolumn. Detection for antibodies was performed using ID-Card LISS-Coombs microtubes, in solid phase and with tube techniques. For molecular analysis, the FUT1 and FUT2 genes were sequenced using BigDye terminator v1.1. The study of FUT2 gene was performed after extraction of mRNA using Qiagen kit RNase and then reverse-transcribed into cDNA. RESULTS: The Bombay phenotype was confirmed by serological and molecular analysis techniques. The patient, in collaboration with a cultural mediator, was informed of her immunohaematological condition and a program of assistance was proposed to her. Unfortunately the patient did not return for the next visit, despite of a telephone reminder. During childbirth a haemorrhage occurred and a request of compatible blood for an urgent transfusion arrived at our transfusion service. Fortunately, the haemorrhage was arrested and the patient didn't need to have any transfusions. CONCLUSION: This case emphasizes the need for an efficient management of rare blood types that are more and more frequent as a result of migration. It is necessary to organize, in strategic points of the national territory, reference centres with better diagnostic capabilities and implement freezing of red blood cells with rare phenotype for diagnostic and therapeutical use. Communication issues are as well important in dealing with this emerging phenomenon.

The role of the direct antiglobulin test in pre-transfusion investigations and the approach to selecting blood for transfusion in autoimmune haemolytic anaemia: results of a regional survey.

INTRODUCTION: The aim of this study was to conduct a Regional survey to determine the policies and ways of performing the direct antiglobulin test in pre-transfusion screening, the approach used in cases giving positive results with this test and the technical and operative modalities for choosing blood for transfusion in cases of autoimmune haemolytic anaemia. MATERIALS AND METHODS: A questionnaire, containing ten multiple-choice questions, was sent to all the transfusion centres in the Region of Tuscany. RESULTS: The data from all 40 regional centres were analysed. Direct antiglobulin tests and autocontrols were not regularly used in pre-transfusion screening. The direct antiglobulin test was predominantly reserved for suspected cases of autoimmune haemolytic anaemia. Sixty percent of the laboratories characterised the specificity of samples that were positive for IgG and complement by the direct antiglobulin test, 45% that were positive for IgM, 35% also for IgA, and 13% also for subclasses of IgG. Elution studies were reserved (in 18% of laboratories) for those cases in which it was expected that transfusion therapy would be used. In cases of autoimmune haemolytic anaemia, autologous/allogeneic adsorption was carried out in 27% of the structures (the use of proteolytic enzymes is predominant, followed by the "ZZAP" reagent--a mixture of dithiothreitol and an enzyme) and the dilution method in 20%; transfusion of red blood cells with a phenotype extensively compatible (c, C, D, E, e, K, Jka, Jkb, Fya, Fyb, S, s) with that of the recipient is practised in 17% of the centres, while transfusion of units of "least incompatible" red blood cells was reported by 95% of the centres, but in 88% this is preceded by at least one of the above mentioned immunohaematological investigations. CONCLUSIONS: The organisation of a network of Services of Immunohaematology and Transfusion Medicine can be exploited to overcome some technical and operative limitations of peripheral, dependent Transfusion Sections. The results of this study reveal which immunohaematology laboratory is endowed with the greatest potential and which could, therefore, become the regional reference centre. This investigation could lay the basis for defining behavioural algorithms and recommendations on the issues considered.