A pregnant woman with chronic meningococcaemia from Neisseria meningitidis with lpxL1-mutations

On examination she looked well, with temperature 36·6°C, pulse 80 beats per min, and blood pressure 110/60 mm Hg. N meningitidis is a commensal of the human upper respiratory tract in more than 8% of the adult population worldwide. The main active part of the LOS is the Lipid A moiety, which contains six fatty acyl chains in the most active form.3 The enzyme for the acylation of Lipid A is encoded in the lpxL1-gene, and mutations in this gene result in an underacylated and therefore inactivated Lipid A.4 Because chronic meningococcaemia is associated with lpxL1 mutations in N meningitidis we sequenced the lpxL1-region in our isolate P3485 and identified eight point mutations causing changes in the aminoacid sequence of the lpxL1 gene (appendix).4 We showed that cytokine induction in the host was decreased by our isolate, evidenced by reduced induction of phospho p38 MAPK, phospho NFκB, and IL-6 in human macrophages (appendix).