![](https://thelimbic.com/wordpress/wp-content/uploads/2020/02/MED-lung-transplant-300x175.jpg)
Mr Trieger with partner Elizabeth Bawden (L) and Dr Timothy Wells (R)
Doctors in Queensland have successfully treated a life-threatening P. aeruginosa infection in a post–lung transplant patient with cystic fibrosis by using used plasmapheresis to eliminate inhibitory IgG2 antibodies that were blocking the effects of antibiotics.
The 33-year old man Jordan Trieger had developed pulmonary, pleural, and soft tissue P. aeruginosa infection after undergoing bilateral sequential lung transplantation at The Prince Charles Hospital.
The infection persisted despite surgical drainage and long term treatment with multiple recommended antibiotics.
His treating doctors recognised the situation as similar to some patients with non-CF bronchiectasis who are chronically colonised with P. aeruginosa. These patients have high titres of IgG2 antibodies specific for the O-antigen of lipopolysaccharides (LPSs), which rather than having a bactericidal effect, impair serum-mediated killing of the infecting P. aeruginosa.
“In Jordan’s case, the bacteria was resistant to all forms of conventional therapy we were trying, and he was rapidly deteriorating, so I knew we needed a different treatment option fast,” said Professor Dan Chambers, Queensland Lung Transplant Service’s Head of Research.
Working with researchers at UQ’s Diamantina Institute, they identified that Jordan had P. aeruginosa infection that expressed O-antigen of LPSs and serum containing high titres of the inhibitory IgG2.
They also noted that pooled healthy control serum was able to kill all P. aeruginosa isolates from the patient.