Adherence to vaccination guidelines post splenectomy: A five year follow up study

Case report: Fatal overwhelming post-splenectomy infection in a patient with metastatic angiosarcoma treated with immunotherapy

A patient in his 40s with splenic angiosarcoma metastatic to the liver underwent splenectomy, chemotherapy, and partial hepatectomy before being treated on a clinical trial with CTLA4 and PD1 inhibitors. He had received pneumococcal and meningococcal vaccines post-splenectomy. On week 10, he developed grade 3 immune-related colitis, successfully treated with the anti-tumor necrosis factor-alpha inhibitor infliximab and steroids. After 4 cycles of treatment, scans showed partial response. He resumed anti-PD1 therapy, and 6 hours after the second dose of anti-PD1 he presented to the emergency room with hematemesis, hematochezia, hypotension, fever, and oxygen desaturation. Laboratory tests demonstrated acute renal failure and septicemia (Streptococcus pneumoniae). He died 12 hours after the anti-PD1 infusion from overwhelming post-splenectomy infection (OPSI). Autopsy demonstrated non-viable liver tumors among other findings. In conclusion, patients undergoing immunotherapy and with prior history of asplenia should be monitored closely for OPSI as they may be at increased risk.

Efficacy of a novel patient-focused intervention aimed at increasing adherence to guideline-based preventive measures in asplenic patients: the PrePSS trial

PURPOSE

To determine whether a novel intervention improves the adherence to guideline-based preventive measures in asplenic patients at risk of post-splenectomy sepsis (PSS).

METHODS

We used a prospective controlled, two-armed historical control group design to compare a novel, health action process approach (HAPA)-based telephonic intervention involving both patients and their general practitioners to usual care. Eligible patients were identified in cooperation with the insurance provider AOK Baden-Wuerttemberg, Germany. Patients with anatomic asplenia (n = 106) were prospectively enrolled and compared to a historical control group (n = 113). Comparisons were done using a propensity-score-based overlap-weighting model. Adherence to preventive measures was quantified by the study-specific 'Preventing PSS score' (PrePSS score) which includes pneumococcal and meningococcal vaccination status, the availability of a stand-by antibiotic and a medical alert card.

RESULTS

At six months after the intervention, we estimated an effect of 3.96 (95% CI 3.68-4.24) points on the PrePSS score scale (range 0-10) with mean PrePSS scores of 3.73 and 7.70 in control and intervention group, respectively. Substantial improvement was seen in all subcategories of the PrePSS score with the highest absolute gains in the availability of stand-by antibiotics. We graded the degree of participation by the general practitioner (no contact, short contact, full intervention) and noted that the observed effect was only marginally influenced by the degree of physician participation.

CONCLUSIONS

Patients who had received the intervention exhibited a significantly higher adherence to guideline-based preventive measures compared to the control group. These data suggest that widespread adoption of this pragmatic intervention may improve management of asplenic patients. Health insurance provider-initiated identification of at-risk patients combined with a patient-focused intervention may serve as a blueprint for a wide range of other preventive efforts leading to patient empowerment and ultimately to better adherence to standards of care.

Adherence to vaccination guidelines of patients with complete splenectomy in Norway, 2008-2020

The spleen is responsible for blood filtration and mounting an immune response against pathogens. In some people the spleen must be surgically removed because of traumatic events or oncological and hematological conditions. These patients are at higher risk of developing diseases caused by encapsulated bacteria throughout their lives. Thus, immunisations are advised for splenectomised persons to prevent infection caused by Streptococcus pneumoniae, Neisseria meningitidis and Haemophilus influenzae type b (Hib). This study assessed vaccination coverage (VC) among Norwegian patients with surgical asplenia. Using the Nomesco Classification of Surgical Procedures codes, patient information (age, sex, date of initial diagnosis and date of surgery) was acquired from the Norwegian Patient Registry. The National Immunization Register provided information on vaccination status and data of any subsequent invasive bacterial infections were obtained from the Norwegian Surveillance System for Communicable Diseases. From the total population of Norway, 3155 patients who had undergone complete splenectomy were identified. Of these, 914 (29.0%) had received at least one dose of pneumococcal conjugate vaccine (PCV), 1324 (42.0%) at least one dose of pneumococcal polysaccharide vaccine and 589 (18.7%) had received both. Only 4.2% of the patients had received two doses of a meningococcal ACWY conjugate vaccine, while 8.0% of 1467 patients splenectomised after 2014 had received at least two doses of a serogroup B meningococcal vaccine. The VC for Hib was 18.7%. Nearly all splenectomised children under the age of 10 were vaccinated with Hib and PCV as these vaccines are included in the childhood immunisation program. For all vaccines, VC decreased with age. Twenty-nine invasive bacterial infections were registered post-splenectomy in 25 patients. Vaccination according to national recommendations could have prevented at least 8 (28%) of these infections. Our study showed that efforts are required to increase VC of splenectomised individuals in Norway.

Role of Partial Splenectomy in Hematologic Childhood Disorders

The spleen is a secondary lymphoid organ that belongs to the reticular-endothelial system, directly connected to blood circulation. The spleen is greatly involved in the immune response, especially against capsulated bacteria. Splenectomy plays a fundamental role in the treatment of numerous pediatric hematologic disorders. Taking into account all the possible complications (especially infections) linked to this procedure, alternatives to total splenectomy have been sought. Partial splenectomy has been proposed as a treatment that allows the reduction of infectious risk. This approach has proven safe and feasible in most patients, but multicentric and prospective studies are necessary to more accurately define the indications for performing partial splenectomy. However, vaccinations and antibiotic prophylaxis remain fundamental for preventing serious infections, even in the case of partial splenectomy. We review anatomical and functional properties of the spleen, with a focus on medical or surgical indications to splenectomy, aiming to give practical educational information to patients and their families after splenectomy. Furthermore, we discuss the feasibility of partial splenectomy in children with hematologic diseases who require splenectomy.

Immunization coverage among asplenic patients and strategies to increase vaccination compliance: a systematic review and meta-analysis

BACKGROUND

Asplenic or splenectomized patients have a higher risk (ranging from 10 to 50-fold) than the general population of developing an overwhelming post-splenectomy infection (OPSI). Thus, they should receive specific vaccinations to prevent bacterial infections and influenza. The aim of this meta-analysis was to estimate vaccination coverage (VC) with the recommended vaccines among splenectomized patients; strategies recommended in those studies to improve VC worldwide are considered as well.

RESEARCH DESIGN AND METHODS

Scopus, MEDLINE/PubMed, Google Scholar and ISI Web of Knowledge databases were searched. Research papers, short reports, reviews, and meta-analyses published between January 1, 2010 and July 18, 2020 were included; no geographic restrictions were included. Twenty-four studies were included in the meta-analysis.

RESULTS

For anti-pneumococcal vaccination, coverage was 55.1% (95%CI = 41.0-69.2%), for anti-Hib 48.3% (95%CI = 34.3-52.3%), for anti-meningococcal C/ACYW135 33.7% (95%CI = 23.6-43.9%), for anti-meningococcal B 13.3% (95%CI = 7.0-19.5%) and for anti-influenza 53.2% (95%CI = 22.0-84.4%). Most studies determined a lack of adherence to international guidelines by healthcare workers and suggested the need to better educate health professionals in the management of post-splenectomy patients.

CONCLUSIONS

The meta-analysis showed the suboptimal immunization coverage for the vaccines recommended for asplenic patients. Greater efforts must be made by public health professionals to increase VC in this group of patients at risk. Introducing specific prophylaxis protocols in the clinical routine seems to guarantee better immunization compliance in those patients.

Meningococcal vaccination in patients with newly diagnosed asplenia in the United States

BACKGROUND

Patients with asplenia are recommended to receive meningococcal ACWY (MenACWY) and B (MenB) vaccines in the United States (US).

OBJECTIVES

To examine uptake and time to receipt of meningococcal vaccines in newly diagnosed asplenia patients, and identify factors associated with vaccination.

METHODS

For this retrospective database analysis, patients were identified from 1/1/2010 (MenACWY) or 1/1/2015 (MenB) through 3/31/2018 from an administrative claims database including commercially insured US patients with ≥1 inpatient or ≥2 outpatient claims with evidence of a new asplenia diagnosis (sickle cell disease was excluded); continuous enrollment for ≥12 months before and ≥6 months after the index date; and age ≥2 (MenACWY) or ≥10 (MenB) years. Co-primary outcomes were uptake and time to receipt of ≥1 dose, separately for MenACWY and MenB, by Kaplan-Meier analysis. Cox proportional hazards regression models were used to identify characteristics associated with vaccination.

RESULTS

Among 2,273 and 741 patients eligible for the MenACWY and MenB analyses, respectively, 28.1% and 9.7% received MenACWY and MenB in the first 3 years after a new asplenia diagnosis. Patients were more likely to receive meningococcal vaccines if they had received pneumococcal vaccines (MenACWY: hazard ratio [HR] 26.02; 95% confidence interval [CI] 21.01-32.22; MenB: HR 3.89; 95% CI 2.07-7.29) or attended ≥1 well-care visit (MenACWY: HR 6.63; 95% CI 4.84-9.09; MenB: HR 11.17; 95% CI 3.02-41.26).

CONCLUSIONS

Meningococcal vaccination rates among newly diagnosed asplenia patients were low, highlighting the need to educate providers about the recommendations for high-risk conditions and ensure healthcare access for vulnerable patients.

Effect of Post-splenectomy Booster Vaccine Program on Vaccination Compliance in Trauma Patients

OBJECTIVE

In 2012, the Centers for Disease Control and Prevention (CDC) Advisory Council on Immunization Practice recommended an additional post-splenectomy booster vaccine at 8 weeks following the initial vaccine. The objective of this study was to evaluate our vaccination compliance rate and what sociodemographic factors were associated with noncompliance following this recommendation.

MATERIALS AND METHODS

A retrospective review of a performance improvement database of trauma patients eligible for post-splenectomy vaccination (PSV) at a level I trauma center was carried out between 2009 and 2018. Overall and institutional compliance with PSV was compared before and after the addition of booster vaccine recommendation. Factors associated with booster noncompliance were also identified.

RESULTS

A total of 257 patients were identified. PSV compliance rate in the pre-booster was 98.4%, while overall and institutional post-booster compliance rate were significantly lower at 66.9% (P ≤ .001) and 50.0% (P ≤ .001), respectively. Compared to booster institutional compliers, institutional noncompliers lived farther from the trauma center (48 vs. 86 miles, P = .02), and though not statistically significant, these patients were generally older (34.9 vs. 40.5, P = .05).

DISCUSSION

PSV booster compliance is low even with the current educational materials and recommendations. Additional approaches to improve compliance rates need to be implemented, such as sending letters to the patient and their primary care providers (PCPs), collaborating with rehab/long-term acute care centers, communicating with city and county health departments and city pharmacies, or mirroring other countries and creating a national database for asplenic patients to provide complete information.

Perioperative Immunization for Splenectomy and the Surgeon's Responsibility: A Review

Importance

Patients who have had splenectomy have a lifelong risk of overwhelming postsplenectomy infection (OPSI), a condition associated with high mortality rates. Surgeons must be aware of the rationale of vaccination in the case of splenectomy, to provide appropriate immunization in the perioperative time.

Observations

English-language articles published from January 1, 1990, to December 31, 2019, were retrieved from MEDLINE/PubMed, Cochrane Library, and ClinicalTrials.gov databases. Randomized clinical trials as well as systematic reviews and observational studies were considered. Asplenia yields an impairment of both innate and adaptive immunity, thus increasing the risk of severe encapsulated bacterial infections. Current epidemiology of OPSI ranges from 0.1% to 8.5% but is hard to ascertain because of ongoing shifts in patients' baseline conditions and vaccine penetration. Despite the lack of randomized clinical trials, immunization appears to be effective in reducing OPSI incidence. Unfortunately, vaccination coverage is still suboptimal, with a great variability in vaccination rates being reported across institutions and time frames. Notably, current guidelines do not advocate any particular health care qualification responsible for vaccine prescription or administration. Given the dearth of high-level basic science or clinical evidence, the optimal vaccination timing and the need for booster doses are not yet well established. Although almost all guidelines indicate to not administer vaccines within 14 days before and after surgery, most data suggest that immunization might be effective even in the immediate perioperative time, thus placing the surgeon in a primary position for vaccine delivery. Furthermore, revaccination schedules are the target of ongoing debates, since a vaccine-driven hyporesponsiveness has been postulated.

Conclusions and Relevance

In patients who have undergone splenectomy, OPSI might be effectively prevented by proper immunization. Surgeons have the primary responsibility for achieving adequate, initial immunization in the setting of both planned and urgent splenectomy.

Prevention of infection in asplenic adult patients by general practitioners in France between 2013 and 2016 : Care for the asplenic patient in general practice

Background

Guidelines that detail preventive measures against Streptococcus pneumoniae, Neisseria meningitidis, Haemophilus influenzae type b, and influenza are published annually in France to decrease the risk of severe infections in immunocompromised patients. We aimed at describing adherence to these guidelines by GPs in the management of their asplenic patients in France between 2013 and 2016.

Method

We conducted a multicenter retrospective study between January 2013 and December 2016 in three French hospitals: asplenic adults were identified and their GPs were questioned. A descriptive analysis was performed to identify the immunization coverage, type and length of antibiotic prophylaxis, number of infectious episodes, and education of patients.

Results

103 patients were finally included in this study: only 57% were adequately vaccinated against Streptococcus pneumoniae or Neisseria meningitidis, 74% against Haemophilus influenzae type b, and 59% against influenza. Only 24% of patients received a combination of all four vaccinations. Two-thirds of patients received prophylactic antibiotics for at least 2 years. Overall, this study found that 50% of splenectomized patients experienced at least one pulmonary or otorhinolaryngological infection, or contracted influenza.

Conclusions

These data match those reported in other countries, including Australia and the United Kingdom, meaning a still insufficient coverage of preventive measures in asplenic patients. Improved medical data sharing strategies between healthcare professionals, along with educational measures to keep patients and physicians up to date in the prevention of infections after splenectomy would improve health outcomes of asplenic patients.

Increased long-term pneumonia risk for the trauma-related splenectomized population - a population-based, propensity score matching study

BACKGROUND

Splenectomy is the life-saving treatment for high-grade spleen trauma. Splenectomized patients are at a significant infection risk. However, the trauma-induced splenectomy results in less incidence of postsplenectomy infection than the hematologic disorder. We conducted a large-scale study to identify the infection rate and management strategy in trauma-related splenic injuries.

METHODS

We included patients with the diagnosis of spleen injury in Taiwan from January 2003 to December 2013 by using the National Health Insurance Database and divided them into spleen preserved and splenectomized groups. The demographic factors including age, sex, hospital level, year of injury, trauma mechanism, associated injuries, whether injury severity score ≧16, and comorbidities were extracted. A 1:1 propensity score match was performed, and we analyzed the long-term outcome as the presence of infection-related disease (septicemia, pneumonia, and meningitis) after spleen trauma. The multivariate logistic regression analysis was used to identify the risk factor for each outcome.

RESULTS

During the 11 years included in this study, a total of 8,897 patients with spleen trauma were identified. A total of 3,520 (39.6%) patients were splenectomized, and 5,377 (60.4%) were spleen preserved. After propensity score matching, 3,099 pairs of patients were enrolled for further analysis. In univariate analysis, the incidence of pneumonia is significantly higher in the splenectomized group (8.5% vs 7.0%, P = .037). There was no significant difference in septicemia and meningitis between the 2 groups. In multivariate analysis, splenectomy is an independent risk factor for pneumonia in long-term follow-up.

CONCLUSION

Compared with the spleen preserved group, splenectomy is related to an increased likelihood of long-term pneumonia onset but not to an increase in the possibility of other infections.

Post-splenectomy sepsis: preventative strategies, challenges, and solutions

Removal of the spleen had already been established as a routine technique to treat splenic trauma and other diseases affecting the spleen before the anatomy, physiology, and function of the spleen were known in the mid-twentieth century. It is now widely accepted that the splenectomized individual is at increased risk for infection, in particular, overwhelming post-splenectomy infection (OPSI). OPSI is a syndrome of fulminant sepsis occurring in splenectomized (asplenic) or hyposplenic individuals that is associated with high mortality and morbidity. Poorly opsonized bacteria such as encapsulated bacteria, in particular, Streptococcus pneumoniae, are often implicated in sepsis. The spleen is a reticuloendothelial organ that facilitates opsonization and phagocytosis of pathogens, in addition to cellular maintenance. Splenectomy is associated with an impairment in immunoglobulin production, antibody-mediated clearance, and phagocytosis, leading to an increased risk of infection and sepsis. Early identification of the at-risk patient, early blood cultures prior to antibiotic administration, urgent blood smears and fast pathogen-detection tests, and sepsis bundles should be utilized in these patients. Prompt management and aggressive treatment can alter the course of disease in the at-risk splenectomized patient. Overwhelming post-splenectomy infection can be prevented through vaccination, chemoprophylaxis, and patient education. This article evaluates post-splenectomy sepsis by summarizing the anatomy and function of the spleen, physiological changes after splenectomy that predispose the splenectomized patient to infection, and current management and prevention strategies.

Vaccination and splenectomy in Olmsted County

OBJECTIVES

To determine the long-term impact of vaccination on any postoperative infection in adults who underwent splenectomy.

METHODS

All adults (≥18 years) who underwent splenectomy from 1965 to 2011 in Olmsted County, MN were identified using the Rochester Epidemiology Project. Descriptive statistics, Kaplan-Meier estimates, and Cox proportional hazard ratios were performed.

RESULTS

There were 724 patients who underwent splenectomy; 47% were female with a median age of 55 (35-69) years. Overall vaccination rate (pneumococcal, H influenza, meningococcal) was 62% (n = 449). There were 268 (36%) patients who developed a post-splenectomy infection; most presented with sepsis 148 (55%). The 3 most common infections included pneumonia (124, 17%), bloodstream (67, 9%), and urinary tract infection (49, 7%). Median time to infection was quicker in non-vaccinated compared with vaccinated patients (1.5 [0.1-4.3] vs 3.3 [1.9-9.8] years, P = .01).

CONCLUSION

In this population-based study, the highest risk of infection after splenectomy was in patients who did not receive complete vaccination. Lack of complete vaccination was associated with a reduced time to infection and increased rates of bloodstream infections at 5 years. Infectious complication risk reduced as vaccination protocols improved for all indications except for malignancy. Adults who underwent a splenectomy should continue to receive booster vaccines.

Blunt splenic injury in children: haemodynamic status key to guiding management, a 5-year review of practice in a UK major trauma centre

PURPOSE

To review the management of children and adolescents (0-18 years), with blunt splenic injury treated at a single UK major trauma centre over a 5-year period, focusing upon efficacy of non-operative management and the use of haemodynamic stability as a guide to planning treatment strategy, rather than radiological injury grading. To produce a treatment pathway for management of blunt splenic injury in children.

METHODS

Retrospective, cross-sectional study of all paediatric patients admitted with radiologically proven blunt splenic injury between January 2011 and March 2016. Penetrating injuries were excluded. Follow up was for at least 30 days.

RESULTS

30 Patients were included, mean age was 14.5 (SD 3.6), median injury severity score was 16 (IQR 10-31). 6 Patients (20%) had a splenectomy, whilst 22 patients (73%) were successfully treated non-operatively with 100% efficacy at index admission. 5/8 (63%) patients with radiological grade V injuries were managed non-operatively, injury grade was not associated with surgical intervention (p = 1.57). Haemodynamic instability was initially treated with fluid resuscitation leading to successful non-operative management in 5/11 (45%) patients. However, haemodynamic instability is a significant predictor of requirement for surgical intervention (p = 0.03), admission to critical care (p = 0.017), presence of additional injuries (p = 0.015) and increased length of stay (p = 0.038). No such relationships were found to be associated with increased radiological injury grade.

CONCLUSIONS

Non-operative management should be first-line treatment in the haemodynamically stable child with a blunt splenic injury and may be carried out with a high degree of efficacy. It may also be successfully implemented in those initially showing signs of haemodynamic instability that respond to fluid resuscitation. Radiological injury grade does not predict definitive management, level of care, or length of stay; however, haemodynamic stability may be utilised to produce a treatment algorithm and is key to guiding management.

Impact of a spleen registry on optimal post-splenectomy vaccination and care

Objective: To evaluate quality of patient knowledge and rates of adherence to guidelines amongst splenectomised patients registered to the Spleen Australia registry. Method: Registrants recruited for assessment of residual splenic function post-splenectomy also underwent an assessment of quality of knowledge and a review of their long-term management. Eligible patients were ≥ 18 years of age, registered to the Spleen Australia clinical registry and had been splenectomised at least 1 year prior to their visit. Quality of knowledge was assessed using a validated questionnaire used in similar studies. Receipt of immunisations was validated by record review. Chemoprophylaxis use was self-reported by patients. Adherence was evaluated using Australian guidelines. Results: 77 patients were evaluated for education and adherence. 58% were female, mean age was 58 years, and median duration since splenectomy was 14 years. Most common indications for splenectomy were trauma and haematological conditions. 77% had good knowledge of key educational points to reduce chances of infection. Adherence to immunisations varied with poor adherence to vaccines introduced after 2010. Only 6 patients were adherent to all recommended immunisations. Increasing duration since registration was associated with poorer 13vPCV (p = 0.008) and 4vMenCV adherence (p = 0.001). Over 70% either currently or had previously used daily chemoprophylaxis and 66% had a supply of emergency antibiotics. Conclusions: Although registrants are receiving initial and booster vaccinations, they do not receive newly recommended vaccines. In order to maintain long-term adherence, we recommend streamlining health information systems, improving awareness strategies and improving financial access to vaccinations in the community with additional awareness of the activities of the registry.

Vaccination coverage and mortality after splenectomy: results from an Italian single-centre study

Splenectomy is a well-recognised risk factor for life-threatening overwhelming post-splenectomy infection (OPSI). To prevent OPSI, immunisations against encapsulated bacteria (S. pneumoniae, N. meningitidis, H. influenzae) and influenza virus are recommended. However, there is still a lack of uniformity and poor compliance with these recommendations. Following a local physicians' awareness campaign regarding the importance of vaccine prophylaxis of splenectomised patients, we aimed to register vaccination coverage, mortality and infection rates in all patients who underwent splenectomy at our hospital, over a six-year time span. Reasons for splenectomy, patients' compliance with vaccinations, mortality and infectious events were recorded. The reasons for splenectomy in the 216 identified patients (mean age 58.2 ± 14; M:F ratio 1.4:1) were haematologic disorders (38.8%), solid tumours (28.7%), traumatic rupture (22.7%) and other causes (9.7%). A total of 146 patients (67.6%) received at least one of the four vaccines. Overall, the mortality rate was significantly greater in unvaccinated compared to vaccinated patients (p < 0.001), although after the adjustment for the cause of splenectomy the statistical significance was lost (p = 0.085) due to the burden of solid tumour-related mortality. Among the 21 reported cases of OPSI, eight were fatal and five were potentially vaccine-preventable. Our results show that two-thirds of splenectomised patients comply with vaccine prophylaxis. Future interventional studies or ad hoc registries might overcome barriers to vaccination or intentional non-compliance.

Splenic vessel preservation versus splenic vessel resection in laparoscopic spleen-preserving distal pancreatectomy

BACKGROUND

Laparoscopic spleen-preserving distal pancreatectomy for low-grade malignant pancreas tumours was recently demonstrated and can be performed with splenic vessel preservation (SVP) or splenic vessel resection (SVR). Whether one approach is superior to another is still a matter of debate.

METHODS

A systematic literature search (PubMed, Embase, Science Citation Index, Springer-Link and Cochrane Central Register of Controlled Trials) was performed. Pooled intra- and post-operative outcomes were evaluated. Stratified and sensitivity analyses were performed to explore heterogeneity between studies and to assess the effects of the study qualities.

RESULTS

A total of six studies were included. There was no significant difference for SVR and SVP in terms of overall post-operative complications and the pooled odds ratio (OR) was 0.87 (95% confidence interval (CI) 0.55-1.38, I² = 25%). Meta-analysis on the pooled outcome of intraoperative operative time and blood loss favoured SVR; the mean differences were 18.64 min (95% CI 6.91-30.37 min, I² = 21%) and 65.67 mL (95% CI 18.88-112.45 mL, I² = 48%), respectively. Subgroup analysis showed a decrease incidences in perigastric varices (OR = 0.07, 95% CI 0.03-0.18, I² = 29%) and splenic infarction (OR = 0.16, 95% CI 0.08-0.32, I² = 0%) in SVP.

CONCLUSION

For selected patients who underwent laparoscopic spleen-preserving distal pancreatectomy, an increased preference for the SVP technique should be suggested considering its short-term benefits. However, in case of large tumours that distort and compress vessel course, SVR could be applied with acceptable splenic ischaemia and perigastric varices.