The partnership is acquiring France-based Cerba from PAI Partners and the firm’s clinical pathologists and managers.

With around 4,300, employees, Cerba operates clinical pathology laboratories in France, Belgium and Luxembourg

The firm also offers specialty lab testing services for complex medical diagnoses, in addition to testing services for clinical trials.

Its clients comprised of private patients, physicians, labs, private and public hospitals, retirement and nursing homes, and pharmaceutical and biotech companies.

Cerba reported revenues of around €630m in 2016.

Partners Group and PSP Investments will work with Cerba's management team to expand the business, following the completion of the acquisition.

Cerba HealthCare CEO Catherine Courboillet said: "Cerba has enjoyed tremendous growth in the past decade. When we approached the transition to new ownership, we focused on finding partners who would not only support a continuation of this pace of growth, but could also bring valuable support in international development.

“We believe we have found the right partners in Partners Group and PSP Investments and look forward to working together with them to further build on Cerba's market-leading position."

“Partners Group’s Private Equity Europe managing director Kim Nguyen said: "Cerba is a resilient market leader in a highly attractive and fragmented sub-sector of the healthcare industry.”