Transfusion-associated graft versus host disease (TAGVHD)--with reference to neonatal period.

Transfusion-associated graft versus host disease [TAGVHD] results from the engraftment of transfused immuno-competent cells in blood transfusion recipients, whose immune system is unable to reject them. All blood products containing viable, immuno-competent T cells have been implicated in TAGVHD. Presence of a "one-way HLA match between donor and recipient" is associated with a significantly increased risk of TAGVHD. Though sharing of haplotype is the most probable explanation, it is far from adequate. Since TAGVHD is not seen in patients with AIDS, and an acute GVHD-like syndrome has been noted in some identical twins and autologous (self) transplants, some other processes, possibly of an "autoimmune" nature are responsible for TAGVHD. Most of the cases have been reported from Japan. This clustering in space and time is rather intriguing. We offer here alternative hypothesis. Foetal and then neonatal lymphocytes exhibit tolerance towards donor cytotoxic T lymphocytes; and consequently very few cases of TAGVHD have been reported in neonates than expected. This tolerance is a part of altered immunology of pregnancy. We feel that it is possible to use maternal blood for transfusion to her newborn baby by following certain protocol and procedure and TAGVHD is no barrier.