Cord blood transplantation (CBT) is curative for many primary immunodeficiencies (PIDs) but is associated with risks of viral infection and graft-versus-host disease (GvHD). Serotherapy reduces GvHD but potentially increases the risk of viral infection by delaying immune reconstitution. Because many PID patients have pre-existing viral infections, the optimal dose of serotherapy is unclear. We performed a retrospective analysis in 34 consecutive PID patients undergoing CBT and compared immune reconstitution, viral infection, GvHD, mortality, and long-term immune function between high-dose (n = 11) and low-dose (n = 9) serotherapy. Serotherapy dose had no effect on neutrophil engraftment. Median CD3(+) engraftment occurred at 92.5 and 97 days for high- and low-dose serotherapy, respectively. The low-dose serotherapy group had higher CD3(+), CD4(+), and early thymic emigrant counts at 4 months compared with the high-dose group. GvHD severity and number of viral infections did not differ between serotherapy doses. Survival from the transplantation process was 90.9% for high-dose and 100% for low-dose groups. In conclusion, low-dose serotherapy enhanced T cell reconstitution and thymopoiesis during the first year after CBT with no increase in GvHD.

The coagulant effects of Australasian black snakes (Pseudechis spp.) are poorly understood and differ to the procoagulant venoms of most dangerous snakes in Australia. This study aimed to investigate in vitro coagulant effects of Pseudechis venoms and the efficacy of commercial black snake antivenom (BlSAV), tiger snake antivenom (TSAV) and specific rabbit anti-snake IgG to neutralise these effects. Using a turbidimetric assay, all six Pseudechis venoms had anticoagulant activity, as well as phospholipase A(2) (PLA(2)) activity. Inhibition of PLA(2) activity removed anticoagulant effects of the venoms. Pseudechis porphyriacus was unique and had procoagulant activity independent of PLA2 activity. Both BlSAV and TSAV completely inhibited the coagulant and PLA2 activity of all Pseudechis venoms. PLA2 activity was also inhibited completely by p-Bromophenacyl bromide (pBPB) and partially by specific anti-N. scutatus IgG antibodies. Anti-N. scutatus IgG also completely inhibited anticoagulant activity of Pseudechis venom. All Pseudechis venoms showed immunological cross reactivity with specific anti-snake IgG antibodies to P. porphyriacus, Pseudechis australis and Notechis scutatus. Pseudechis venoms have in vitro anticoagulant activity that appears to be attributable to PLA(2) activity. Both antivenoms inhibited anticoagulant and PLA(2) activity at concentrations below those occurring in patients treated with one vial of antivenom. There was cross-neutralisation of Pseudechis venoms and N. scutatus antibodies that might be attributable to immunological similarities between the venoms.

No abstract

Bacterial sepsis led to multiorgan failure in persons receiving immunosuppressive and antiinflammatory drugs.