Haemolysis, pure red cell aplasia and red cell antibody formation associated with major and bidirectional ABO incompatible haematopoietic stem cell transplantation.

BACKGROUND: Acute and delayed haemolysis, alloimmunisation and pure red cell aplasia (PRCA) are potential complications after ABO incompatible haematopoietic stem cell transplantation (HSCT). The aims of this study were to investigate acute and delayed red blood cell (RBC) antibody-associated complications, including haemolysis, PRCA and alloimmunisation in major and bidirectional ABO incompatible HSCT. MATERIALS AND METHODS: We retrospectively examined the transplant courses of 36 recipients of bone marrow or peripheral blood stem cells from ABO incompatible donors and evaluated the current practice of performing plasmapheresis in patients with higher isoagglutinin titres. We investigated the role of ABO incompatibility in haematopoietic recovery, transfusion requirements, alloimmunisation and PRCA. RESULTS: Laboratory signs of acute haemolysis were noted in five (14%) patients, one (3%) of whom had clinically overt haemolysis. Patients with haemolysis had IgM titres ≥1:8 and received >16 mL of RBC in the HSCT. In patients with higher titres, plasmapheresis performed prior to the transplant prevented acute haemolysis. Delayed haemolysis was not recorded in the follow up. Haematopoietic recovery and transfusion requirements did not differ notably between patients with and without haemolysis. De novo RBC antibodies were detected in two (5.5%) patients after HSCT, and PRCA was noted in one (3%) patient. DISCUSSION: Carried out with adequate graft processing, plasmapheresis and blood component support, haemolysis is not a common complication after HSCT. Our results confirm that the occurrence of haemolysis depends on larger RBC volumes and higher isoagglutinin titres. Despite the reduction of patients' isoagglutinin titres by plasmapheresis, we still noted a critical combination for the development of laboratory signs of haemolysis (IgM titre ≥1:8 and RBC volume >16 mL). De novo immunisation to RBC antigens and PRCA are rare events following ABO incompatible HSCT.

[ISKRA guidelines on sore throat: diagnostic and therapeutic approach--Croatian national guidelines]. / Smjernice iskra za grlobolju: dijagnosticki i terapijski pristup--Hrvatske nacionalne smjernice.

Sore throat is most commonly caused by viruses, but when caused by bacteria, the most important is group A streptococcus (GAS). The aim of these guidelines is to determine optimal treatment for streptococcal sore throat and reasonable indications for tonsillectomy, as well as recommend how to differentiate streptococcal infection for which antibiotics are justified, from numerous other sore throats where antibiotics wont have a significant effect on disease course, but might contribute to bacterial resistance to antibiotics. The development of the guidelines was initiated by the Interdisciplinary Section for Antibiotic Resistance Control (ISKRA) of the Croatian Ministry of Health and Social Welfare in accordance with the principles of AGREE (Appraisal of Guidelines for Research and Evaluation) methodology which means that the guidelines are the result of consensus between all interested professional societies and institutions. For streptococcal sore throat diagnostics, the Working Group recommends evaluation of clinical presentation according to Centor criteria and for patients with Centor score 0-1, antibiotic therapy is not recommended nor bacteriological testing, while for patients with Centor score 2-4 bacteriological testing is recommended (rapid test or culture) as well as antibiotic therapy in case of positive result. The drug of choice for the treatment of streptococcal tonsillopharyngitis is oral penicillin taken for ten days (penicillin V) or in case of poor patient compliance benzathine penicillin G can be administered parenterally in a single dose. Other antibiotics (macrolides, clindamycin, cephalosporins, co-amoxiclav) are administered only in case of hypersensitivity to penicillin or in recurrent infections. Tonsillectomy is a widely accepted surgical procedure that decreases the number of sore throats in children and should be performed only if indications for this procedure are established. Absolute indications include five or more streptococcal infections per year, tonsillitis complications, permanent respiratory tract obstruction, obstructive sleep apnea syndrome and suspected tonsillar malignancy. Relative indications include chronic tonsillitis and occlusion disturbances.