LXLP v St George's University Hospitals NHS Foundation Trust

In medical negligence claims involving multiple possible causes of an indivisible injury, the claimant must ordinarily prove on the balance of probabilities that the defendant’s breach caused the injury. Evidence that treatment generally improves outcomes or reduces risk does not itself establish individual causation.

Where material contribution is relied on, the claimant must show more than a negligible contribution to the injury. The doctrine does not convert contribution to risk into contribution to injury, nor permit a general statistical improvement in outcomes to establish reduced severity in a particular case. National clinical guidance is evidence of the standard of care, not a rule. A responsible body of medical opinion must also have a sound and logical basis, including consideration of comparative risks and benefits.

The claimant, a child acting by her mother and litigation friend, claimed damages for cerebral palsy allegedly caused by negligent management of pre-term pre-labour rupture of membranes in April and May 2016. The defendant admitted that Erythromycin should have been prescribed but denied that failure to prescribe additional penicillin for identified group B streptococcus was negligent.

The central issues were whether omitting penicillin was a breach of duty and, if Erythromycin or combined Erythromycin and penicillin had been given, whether either treatment would probably have prevented or materially reduced the chorioamnionitis, foetal inflammatory response and periventricular leukomalacia causing the claimant’s cerebral palsy.

1. Breach of duty. The Bolam test, as qualified by Bolitho, required the court to determine whether the relied-on medical opinion was responsible and had a sound and logical basis. In a case involving competing risks and benefits, the experts had to have directed their minds to that comparison. National and local guidance were relevant evidence, but neither was a legal rule.
2. The national guidance recommended Erythromycin following PPROM but did not recommend oral penicillin specifically for GBS colonisation before labour. The court accepted the evidence supporting the national guidance and the risks of disrupting the vaginal bacterial balance. Acting in accordance with the national guidance, rather than the hospital’s local guideline, was therefore not negligent.
3. Causation. The orthodox “but for” test applied. The evidence showed that antibiotics generally reduced infection and increased latency, but did not establish that Erythromycin would have prevented chorioamnionitis or prolonged this pregnancy beyond approximately one week. A one-week prolongation would not have avoided the claimant’s PVL. The range and variability of possible microorganisms and causal pathways also prevented proof that either Erythromycin alone or combined treatment would probably have prevented the injury.
4. The court applied the reasoning summarised in Holmes v Poeton Holdings Ltd, Bailey v Ministry of Defence and Williams v Bermuda Hospitals Board. A claim fails where the injury is likely to have resulted from one or more disparate factors, including a non-tortious factor, without proof that the defendant’s factor caused it or operated cumulatively to cause it.
5. The material-contribution case failed. The injury did not have the relevant characteristics of an indivisible disease, and, even if it did, the evidence did not show a more than negligible contribution to the brain injury. General evidence of improved outcomes could not be equated with reduced severity of PVL in this claimant.
6. The claim was dismissed.