Would you consider bone marrow transplant in a pediatric patient with recurrent HLH with no identified exogenous trigger or HLH-associated mutation?  

Yes, per published guidelines, it would be considered the standard of care to perform a BMT on a patient with recurrent HLH, regardless of the cause. This patient is presumed to have a genetic mutation that leads to the pathogenesis of HLH.Jordan et al., PMID 31339233