Vaccinations increased serotype protection in children with idiopathic nephrotic syndrome

DENVER — Administration of the 13-valent pneumococcal conjugate vaccine increased protection against Streptococcus pneumoniae that induce higher titers and better serotype coverage in patients with idiopathic nephrotic syndrome, researchers reported here at the 2013 Interscience Conference on Antimicrobial Agents and Chemotherapy.

“Patients with idiopathic nephrotic syndrome are immunocompromised and more vulnerable to vaccine-preventable infectious agents, such as S. pneumoniae or varicella-zoster virus,” researchers wrote.

The study, which included 51 children with nephrotic syndrome, examined S. pneumoniae specific and varicella-zoster virus specific immunoglobulin G titers at baseline, with follow-up at 3 and 12 months after one to two doses of PCV13 (Prevnar 13, Pfizer) and two doses of the varicella-zoster virus vaccine, depending on protection at baseline and current treatment.

Researchers found that, at baseline, 86% of patients were protected against at least four of six S. pneumonia serotypes and 82% against varicella-zoster virus. Previous PCV predicted protection against serotype 23F (OR=7.1; 95% CI, 1.2-41.9).

Higher varicella-zoster virus specific IgG titers were predicted by younger age at varicella-zoster virus disease (P<.001) and longer delay between varicella-zoster virus disease and nephrotic syndrome disease onset (P=.016).

Forty-two participants received PCV13, and S. pneumoniae specific IgG titers increased significantly at months 3 and 12 for the three serotypes included in the vaccine (P<.001). Five non-seroprotected participants received the varicella-zoster virus vaccine and three maintained protection 8 to 10 months after vaccination.

Laure Pittet

“Therefore, based on this first study on PCV13 in children with nephrotic syndrome, we strongly recommend PCV13 immunization in this population, regardless of current treatment and previous immunization history,” Laure Pittet, an MD-PhD student at Geneva’s Children Hospital, told Infectious Diseases in Children. “Regarding varicella, physician should assess patients’ serology at the time of the diagnosis of nephrotic syndrome, immunize seronegative patients fulfilling specific safety criteria and, subsequently, confirm seroconversion after vaccination.”

For more information:
Pittet LF. Abstract B-499. Presented at: ICAAC 2013; Sept. 9-13, 2013; Denver.

Disclosure: The researchers report no relevant financial disclosures.