Conclusions
Ours is a large cohort of TMA following HSCT in children. The prevalence
of TMA in our study is 0.8% with an increasing trend in recent years.
The mortality in our pediatric TMA cohort is 30% which is in contrast
to the higher mortality reported in previously published small case
series. HHV6 emerged as not only a risk factor for TMA but also
associated with increased mortality in these patients. Studies exploring
the pathophysiology of TMA and its relationship to other complications
of HSCT and to prove the effect of HHV6 on complement on a molecular
level are needed to optimize the outcome.
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