Approaches to understanding and interpreting the risks of red blood cell transfusion in neonates.

In this review, we explore how to assess potential harm related to neonatal transfusion practice. We consider different sources of information, including passive or active surveillance systems such as registries, observational studies, randomised trials and systematic reviews. Future research directions are discussed.

Patient blood management, what does this actually mean for neonates and infants?

Patient blood management (PBM) refers to an evidence-based package of care that aims to improve patient outcomes by optimal use of transfusion therapy, including managing anaemia, preventing blood loss and improving anaemia tolerance in surgical and other patients who may need transfusion. In adults, PBM programmes are well established, yet the definition and implementation of PBM in neonates and children lags behind. Neonates and infants are frequently transfused, yet they are often under-represented in transfusion trials. Adult PBM programmes may not be directly applicable to these populations. We review the literature in neonatal (and applicable paediatric) transfusion medicine and propose specific neonatal PBM definitions and elements.

Haemoglobin disorders in Australia: where are we now and where will we be in the future?

Inherited disorders of haemoglobin (Hb), such as thalassaemia and sickle cell disease (SCD) are common and responsible for significant morbidity and mortality on a global scale. As Australia becomes increasingly ethnically diverse, their prevalence will increase. However, we lack important demographic and epidemiological data to manage these disorders and their consequences and to support affected individuals and communities. Thalassaemia and SCD are lifelong conditions. Affected individuals have reduced life expectancies, poorer quality of life and complex healthcare needs. Treatment strategies currently focus on prenatal diagnosis, red blood cell transfusion, iron chelation, management of iron-related complications, haemopoietic stem cell transplantation (HSCT) and hydroxyurea. Currently, the only curative therapy is HSCT; however, gene therapy offers the possibility of cure and trials are currently underway. These therapies are associated with significant complications and substantial costs; there is also evidence of variation in approaches to diagnosis and care. Optimal strategies for many aspects of management are not yet defined and more research is necessary to inform clinical care and health service delivery.

Antibodies to human neutrophil antigen HNA-4b implicated in a case of neonatal alloimmune neutropenia.

BACKGROUND: Maternal alloantibodies directed against human neutrophil antigens (HNAs) can cause moderate-severe neutropenia in the newborn in a condition known as neonatal alloimmune neutropenia (NAIN). Neonates with NAIN can present with sepsis or be asymptomatic. NAIN has previously been reported as caused by antibodies against HNA-1a, -1b, and -1c; CD16b, -2, -3a, -4a, and -5a; and HLA, but not by antibodies against HNA-4b. We report a case of NAIN due to anti- HNA-4b alloimmunization in a term neonate. CASE REPORT: An infant with persistent and marked neutropenia was suspected of having neonatal alloimmune neutropenia. Blood samples from both parents were investigated for HNA and HLA incompatibilities by molecular typing techniques and the mother for the presence of HNA and HLA antibodies by serologic techniques. RESULTS: Initial results indicated the presence of granulocyte antibodies in the maternal serum, the specificity of which were shown to be anti-HNA-4b. Subsequently, the mother was genotyped as HNA-4b negative and the father as heterozygous HNA-4ab. The child was shown to have inherited the incompatible HNA-4b allele. CONCLUSION: We have demonstrated the first case of NAIN due to maternal alloimmunization against HNA-4b, pending ratification by the International Granulocyte Immunobiology Workshop.

Duck virus hepatitis: the effect of attenuation on virus stability in ducklings.

The effect of further attenuation by serial passage in specific pathogen free embryonated hens' eggs, on the stability of the H strain of duck hepatitis virus (DHV) when serially passaged in ducklings was investigated. The 65th, 75th, 86th and 94th passage viruses (H65, H75, H86 and H94) which were considered to be potential vaccines all reverted to virulence on serial passage in ducklings. The virulent Q strain of DHV was similarly attenuated and tested for vaccine potential and stability. Virus passaged serially 10 times was still pathogenic. The 20th and 30th passage virus was apathogenic but did not protect as well as the 40th, 50th, 60th, 70th and 80th passage virus. The 90th passage virus was less protective. All these potential vaccines reverted to virulence on serial passage in ducklings.

Duck virus hepatitis: serial passage of attenuated virus in ducklings.

The safety of three attenuated virus vaccines of proven efficacy against duck virus hepatitis was assessed by controlled laboratory studies which involved the serial transmission of the virus through groups of two-day-old ducklings known to be susceptible to the disease. Each vaccine was initially derived from a different source. Enhancement of virulence which resulted in deaths from the disease in test groups of ducklings occurred in each instance.

Antigens associated with canine spontaneous mammary carcinoma.

Soluble proteins were prepared from canine spontaneous mammary carcinoma (CSMC) cells by extraction with 3M KCl or limited hydrolysis of isolated cell membranes with papain. These preparations were assayed for tumour-associated antigens by inhibition of fully absorbed rabbit antisera. Organ-specific reactivity was demonstrated and antigenic specificity indicated the possible involvement of fetal components. Exclusion chromatography showed that antigenic activity was associated with macromolecules of different sizes in each of the protein preparations which allowed partial purification of tumour-associated antigens. Antigens were also prepared from circulating immune complexes in the serum of tumour-bearing animals. These studies provide a basis for the development of serological markers of malignancy in CSMC.

Active immunisation of ducklings against duck virus hepatitis.

Egg-attenuated duck hepatitis type (Rispens H55) was exhaustively tested as a potential vaccine under controlled conditions in ducklings fully susceptible to the disease at day 2 after hatching. Data are presented which indicate that this vaccine fulfils essential criteria of efficacy in terms of (a) the optimal age at which successful vaccination is practicable (day 2 or earlier), (b) the rapidity of onset of immunity (in 48 to 72 hours), (c) the high level of immunity induced (88.0 to 94.0 per cent), (d) the persistence of this degree of immunity in the individual bird throughout the period when it would otherwise be at risk (until the end of the fourth week of life) and (e) the consistency of the effects of the vaccine in successive groups of ducklings hatched over a four year period. Employed as a vaccine. H55 was completely innocuous to the vaccinated ducklings under laboratory conditions.