[Infection prevention in secondary immunodeficiencies]. / Preventie van infecties bij verworven afweerstoornis.

Over one million people in The Netherlands are estimated having an immunodeficiency, of which the majority has an acquired immunodeficiency due to immunosuppressive medication. These patients are at risk for a more severe course of common infections, and also for opportunistic infections and viral reactivations. The following topics are discussed: types of immunodeficiency and how to estimate its severity; commonly seen infections in immunocompromised patients; recommended screening before start of immunosuppressive medication; pitfalls in clinical clues and diagnostics, and safety and immunogenicity of vaccination in these patients. Conclusively, recognition of an immunodeficiency and awareness of the risks and preventive measures are required. This article attempts to provide a pragmatic classification on the infection risk per type of immunosuppressive medication for clinical practice.

Vena Cava Superior Syndrome Six Years after Central Venous Catheter Removal in a Patient on Hemodialysis.

Vena cava superior (VCS) syndrome is rarely seen as a complication of central-venous-catheter placement. Usually, the syndrome appears when the presence of the catheter causes intraluminal obstruction or thrombosis. In this case report, however, we describe a patient on intermittent hemodialysis who had been free of any venous central line for over 6 years, presented with a VCS syndrome. The CT scan showed an absent VCS without extravascular compression. Previous catheter placement was diagnosed as the case of the VCS syndrome. It is important to realize that VCS syndrome can occur late after removal of central venous catheters, and thus, clinicians should be aware of its symptoms in any patient who has had an upper central line in the past medical history.

Vaccine Responses in Adult Hematopoietic Stem Cell Transplant Recipients: A Comprehensive Review.

Consensus on timing of post-hematopoietic stem cell transplantation (HSCT) vaccination is currently lacking and is therefore assessed in this review. PubMed was searched systematically for articles concerning vaccination post-HSCT and included a basis in predefined criteria. To enable comparison, data were extracted and tables were constructed per vaccine, displaying vaccine response as either seroprotection or seroconversion for allogeneic HSCT (alloHSCT) and autologous HSCT (autoHSCT) separately. A total of 33 studies were included with 1914 patients in total: 1654 alloHSCT recipients and 260 autoHSCT recipients. In alloHSCT recipients, influenza vaccine at 7-48 months post-transplant resulted in responses of 10-97%. After 12 months post-transplant, responses were >45%. Pneumococcal vaccination 3-25 months post-transplant resulted in responses of 43-99%, with the response increasing with time. Diphtheria, tetanus, pertussis, poliomyelitis and Haemophilus influenzae type b at 6-17 months post-transplant: 26-100%. Meningococcal vaccination at 12 months post-transplant: 65%. Hepatitis B vaccine at 6-23 months post-transplant: 40-94%. Measles, mumps and rubella at 41-69 months post-transplant: 19-72%. In general, autoHSCT recipients obtained slightly higher responses compared with alloHSCT recipients. Conclusively, responses to childhood immunization vaccines post-HSCT are poor in comparison with healthy individuals. Therefore, evaluation of response might be indicated. Timing of revaccination is essential for optimal response. An individualized approach might be necessary for optimizing vaccine responses.

Predictive factors for vaccine failure to guide vaccination in allogeneic hematopoietic stem cell transplant recipients.

Vaccination after hematopoietic stem cell transplantation (HSCT) is essential to protect high-risk patients against potentially lethal infections. Though multiple studies have evaluated vaccine specific responses, no comprehensive analysis of a complete vaccination schedule post-HSCT has been performed and little is known about predictors for vaccine failure. In this context, allogeneic HSCT (alloHSCT) patients were included and vaccinated starting one year post-transplantation. Antibody responses were measured by Multiplex Immuno Assay for pneumococcal (PCV13), meningococcal C, diphtheria, pertussis, tetanus and Haemophilus influenza type b one month after the last vaccination and correlated to clinical and immunological parameters. Vaccine failure was defined as antibody response above vaccine-specific cut-off values for less than four out of six vaccines. Ninety-six patients were included of which 27.1% was found to have vaccine failure. Only 40.6% of all patients responded adequately to all six vaccines. In multivariate analysis, viral reactivation post-HSCT (OR 6.53; P = 0.03), B-cells <135 per mm3 (OR 7.24; P = 0.00) and NK-cells <170 per mm3 (OR 11.06; P = 0.00) were identified as predictors for vaccine failure for vaccination at one year post-alloHSCT. Measurement of antibody responses and an individualized approach for revaccination guided by clinical status and immune reconstitution of B-cells and NK-cells may improve vaccine responses.