Physicians Report Barriers to Deliver Best Practice Care for Asplenic Patients: A Cross-Sectional Survey

Background: Current management of asplenic patients is not in compliance with best practice standards, such as defined by the British Committee for Standards in Haematology. To improve quality of care, factors inhibiting best practice care delivery need to be identified first. With this study, we aimed to identify and quantify physicians' barriers to adhere to best practice management of asplenic patients in the Netherlands. Methods and Principal Findings: A cross-sectional survey, preceded by multiple focus group discussions, was performed among Dutch physicians responsible for prevention of infections in asplenic patients, including specialists ( of Internal medicine and Surgery) and general practitioners (GPs). Forty seven GPs and seventy three hospital specialists returned the questionnaire, yielding response rates of 47% and 36,5% respectively. Physicians reported several barriers to deliver best practice. For both GPs and specialists, the most frequently listed barriers were: poor patient knowledge (> 80% of hospital specialists and GPs) and lack of clarity about which physician is responsible for the management of asplenic patients (50% of Internists, 46% of Surgeons, 55% of GPs). Both GPs and hospital specialists expressed to experience a lack of mutual trust: specialists were uncertain whether the GP would follow their advice given on patient discharge (33-59%), whereas half of GPs was not convinced that specialists' discharge letters contained the correct recommendations. Almost all physicians (> 90%) indicated that availability of a national guideline would improve adherence to best practice, especially if accessible online. Conclusion: This study showed that, in accordance with reports on international performance, care delivery for asplenic patients in the Netherlands is suboptimal. We identified and quantified perceived barriers by physicians that prevent adherence to post-splenectomy guidelines for the first time. Better transmural collaboration and better informed patients are likely to improve the quality of care of the asplenic patient population. A national, online-available guideline is urgently require

Response to vaccination in patients immunocompromised due to asplenia, allogeneic stem cell transplantation or chemotherapy

Asplenic individuals are at increased risk for fulminant infections, especially with encapsulated bacteria such as Streptococcus pneumoniae, Haemophilus influenzae type b (Hib) and Neisseria meningitidis, and vaccination is indicated. An inventory was made of the awareness of the infectious risks and vaccination status of asplenic patients in the Netherlands. Less than 50% of the patients did receive adequate information about the infectious risks of their asplenic state. For S.pneumoniae, 88% of patients has received a vaccination. For Hib and Neisseria meningitidis, vaccination rates are considerably lower: 32% and 27% respectively are vaccinated. Only 17% of the patients had received all three vaccines (i.e. pneumococcal, meningococcal and Hib), in accordance with international recommendations. Patients were vaccinated with conjugated Hib, pneumococcal and meningococcal vaccines if they were not vaccinated according to international recommendations. In 92 patients, one dose of conjugated Hib vaccine was given. After a single dose of vaccine, 97% of the patients reached the chosen antibody threshold concentration of ? 1.0 g/mL. The responses to both pneumococcal 23-valent polysaccharide and 7-valent conjugated vaccines were analysed in 54 asplenic patients. After one dose of conjugate pneumococcal vaccine, 82% reached the chosen threshold of ? 1.0 g/mL for 5 out of 7 vaccine-serotypes. This percentage rose to 85% and 92% after a second dose of conjugate vaccine and one dose of polysaccharide vaccine, respectively. In 116 patients, the response to the meningococcal serogroup C (MenC) conjugate vaccine was studied. After a single dose of vaccine, 67% of the patients reached the chosen antibody threshold concentration of ? 2.0 g/mL MenC IgG. The quality of the antibodies (expressed as avidity maturation) was poor. After revaccination of patients with a suboptimal response, the response to vaccination rose from 67% to 78%, but again, with only marginal rise in avidity maturation. In 38 patients with breast cancer, the response to influenza virus vaccination was determined at day 4 or at day 16 of a chemotherapy cycle of 21 days. Patients on chemotherapy have significant lower antibody responses than healthy adults. When comparing the two different moments of vaccination during a chemotherapy cycle, vaccination early during the chemotherapy cycle induces better responses than does vaccination in the last week of the cycle. Follow-up studies in larger patient groups are needed to confirm this effect. The response to pneumococcal, Hib, meningococcal and DTP (diphtheria, poliomyelitis and tetanus) vaccines was studied in 26 patients starting at 12 months after allogeneic stem cell transplantation with reduced intensity conditioning regimens (allo-RIST). After two doses of conjugated pneumococcal vaccines, > 73% of the patients developed antibody levels ? 0.35 g/mL for all pneumococcal serotypes included in the vaccine, except for pneumococcal serotype 6B. For Hib and tetanus toxoid (TT), protective antibody levels were found in 77% and 96% of the patients respectively, after one dose of Hib vaccine and two doses of DTP vaccine. Thus, vaccination of allo-RIST patients starting at approximately 12 months post-transplantation induces adequate antibody concentrations in the majority of patient

Relatively high serum vitamin D levels do not impair the antibody response to encapsulated bacteria

Vitamin D skews the immune system towards a more tolerogenic state. Therefore, a relatively high vitamin D status, i.e., within the normal physiological range, might result in a lower antibody response to infection and vaccination. We hypothesized, however, that vitamin D is primarily important in establishing immune homeostasis, implying that a relatively high vitamin D status would not hamper an adequate antibody response against pathogens. Our results show that the vitamin D status did not differ between responders and hypo-responders in patients infected with Streptococcus pneumoniae, as well as patients vaccinated against S. pneumoniae, Neisseria meningitidis type C (MenC), and/or Haemophilus influenzae type b (Hib). Furthermore, specific IgG titers were not associated with the vitamin D status in patients vaccinated against S. pneumoniae and MenC, while there was a weak inverse association in Hib-vaccinated patients. These data indicate that a relatively high vitamin D status does not seem to hamper an adequate antibody response upon infection or vaccination, suggesting that vitamin D, in this setting, is not immunosuppressive

Antibody Response to Polysaccharide Conjugate Vaccines after Nonmyeloablative Allogeneic Stem Cell Transplantation

After allogeneic stem cell transplantation with reduced-intensity conditioning regimens (allo-RIST) patients are susceptible to bacterial and viral infections for a period that may last several years. The efficacy of the recommended vaccination schedules, in terms of induction of a protective antibody response, is unknown. In this study, the reconstitution of humoral immunity after allo-RIST is determined by measuring the vaccination-induced antibody response against Streptococcus pneumoniae, Haemophilus influenzae type b (Hib), and tetanus toxoid (TT) I year posttransplantation. Patients who underwent allo-RIST were vaccinated according to a schedule starting at 12 months following transplantation with conjugated vaccines against S. pneumoniae, Hib, and TT. Of twenty-six patients both pre- and postvaccination sera were available. Patients were required to be off immunosuppression at the time of vaccination, and, therefore, 9 of the 26 patients did not start vaccination at 12 months post-stem cell transplantation but rather at a median range of 15 (12-36 months) posttransplantation. Except for pneumococcal serotype 613, more than 73% of the patients developed antibody levels >= 0.35 mu g/mL for all pneumococcal serotypes included in the vaccine. For Hib and 71 protective antibody levels were found in 77% and 96% of the patients, respectively. Vaccination of patients at a median of 15 months post-allo-RIST leads to significant rise in concentrations of pneumococcal, Hib, and TT antibodies in the majority of patients. Biol Blood Marrow Transplant 15: 1523-1530 (2009) (C) 2009 American Society for Blood and Marrow Transplantatio