A reassessment of splenic hypofunction in celiac disease

Association between celiac disease and pneumococcal infections in hospitalized pediatric patients in the United States

OBJECTIVE

Celiac disease (CD) is an immune-mediated enteropathy that is associated with pneumococcal infections in adults. The objective of this study is to evaluate the association between CD and pneumococcal infections in hospitalized pediatric patients in the United States (US).

STUDY DESIGN

The triennial Healthcare Cost and Utilization Project Kids' Inpatient Database was used in a retrospective analysis of children hospitalized in the US from 1997 to 2019. Billing codes were used to define patients with CD who were admitted with Streptococcus pneumoniae speciated infections or an infection commonly caused by S. pneumoniae. A multivariable logistic regression model was used to quantify increased odds of various types of infections for patients with CD.

RESULTS

Among 55,080,914 pediatric hospital admissions, 15,412 were identified with CD, and 1,722,872 were admitted with the specified infections. CD was associated with both pneumococcus speciated infections (odd ratio [OR], 2.16, 95% confidence interval [CI], 1.38-3.38) and infections commonly caused by S. pneumoniae (OR, 1.78; 95% CI, 1.61-1.96): pneumonia (OR, 1.70; 95% CI, 1.53-1.89), sinusitis (OR, 2.41, 95% CI, 1.76-3.30), and bacteremia (OR, 2.12; 95% CI, 1.56-2.88). Patients with CD had a significantly longer length of stay (p < 0.001) and a greater cost of hospitalization (p < 0.001) with pneumococcus associated infections.

CONCLUSIONS

CD is associated with an increased risk of both pneumococcus speciated and pneumococcus-associated infections requiring hospitalization. CD admissions are associated with longer hospital stays and higher costs without increased risk of death. Routine pneumococcal vaccinations are strongly recommended for pediatric patients with CD.

High-altitude hypoxia exposure inhibits erythrophagocytosis by inducing macrophage ferroptosis in the spleen

High-altitude polycythemia (HAPC) affects individuals living at high altitudes, characterized by increased red blood cells (RBCs) production in response to hypoxic conditions. The exact mechanisms behind HAPC are not fully understood. We utilized a mouse model exposed to hypobaric hypoxia (HH), replicating the environmental conditions experienced at 6000 m above sea level, coupled with in vitro analysis of primary splenic macrophages under 1% O2 to investigate these mechanisms. Our findings indicate that HH significantly boosts erythropoiesis, leading to erythrocytosis and splenic changes, including initial contraction to splenomegaly over 14 days. A notable decrease in red pulp macrophages (RPMs) in the spleen, essential for RBCs processing, was observed, correlating with increased iron release and signs of ferroptosis. Prolonged exposure to hypoxia further exacerbated these effects, mirrored in human peripheral blood mononuclear cells. Single-cell sequencing showed a marked reduction in macrophage populations, affecting the spleen's ability to clear RBCs and contributing to splenomegaly. Our findings suggest splenic ferroptosis contributes to decreased RPMs, affecting erythrophagocytosis and potentially fostering continuous RBCs production in HAPC. These insights could guide the development of targeted therapies for HAPC, emphasizing the importance of splenic macrophages in disease pathology.

Impaired IgM Memory B Cell Function Is Common in Coeliac Disease but Conjugate Pneumococcal Vaccination Induces Robust Protective Immunity

Coeliac disease (CD) is associated with hyposplenism, an acquired impairment of spleen function associated with reduced IgM memory B cells and increased susceptibility to serious pneumococcal infection. Little is known about the immune implications of hyposplenism in CD or the optimal pneumococcal vaccination strategy. In this study, the immune effects of hyposplenism in CD, and the accuracy of screening approaches and protective responses induced by two different pneumococcal vaccines were examined. Active and treated CD cohorts, and healthy and surgically splenectomised controls underwent testing for the presence of Howell-Jolly bodies and pitted red cells, spleen ultrasound, and immune assessment of IgM memory B cell frequency and IgM memory B cell responses to T cell-dependent (TD) or T cell-independent (TI) stimulation. Responses following conjugate (TD) and polysaccharide (TI) pneumococcal vaccination were compared using ELISA and opsonophagocytic assays. Although hyposplenism is rare in treated CD (5.1%), functional B cell defects are common (28-61%) and are not detected by current clinical tests. Conjugate pneumococcal vaccination induced superior and sustained protection against clinically relevant serotypes. Clinical practice guidelines in CD should recommend routine pneumococcal vaccination, ideally with a conjugate vaccine, of all patients in lieu of hyposplenism screening.

American College of Gastroenterology Guidelines Update: Diagnosis and Management of Celiac Disease

This guideline presents an update to the 2013 American College of Gastroenterology Guideline on the Diagnosis and Management of Celiac Disease with updated recommendations for the evaluation and management of patients with celiac disease (CD). CD is defined as a permanent immune-mediated response to gluten present in wheat, barley, and rye. CD has a wide spectrum of clinical manifestations that resemble a multisystemic disorder rather than an isolated intestinal disease, and is characterized by small bowel injury and the presence of specific antibodies. Detection of CD-specific antibodies (e.g., tissue transglutaminase) in the serum is very helpful for the initial screening of patients with suspicion of CD. Intestinal biopsy is required in most patients to confirm the diagnosis. A nonbiopsy strategy for the diagnosis of CD in selected children is suggested and discussed in detail. Current treatment for CD requires strict adherence to a gluten-free diet (GFD) and lifelong medical follow-up. Most patients have excellent clinical response to a GFD. Nonresponsive CD is defined by persistent or recurrent symptoms despite being on a GFD. These patients require a systematic workup to rule out specific conditions that may cause persistent or recurrent symptoms, especially unintentional gluten contamination. Refractory CD is a rare cause of nonresponsive CD often associated with poor prognosis.

Asplenia and spleen hypofunction

Asplenia (the congenital or acquired absence of the spleen) and hyposplenism (defective spleen function) are common causes of morbidity and mortality. The spleen is a secondary lymphoid organ that is responsible for the regulation of immune responses and blood filtration. Hence, asplenia or hyposplenism increases susceptibility to severe and invasive infections, especially those sustained by encapsulated bacteria (namely, Neisseria meningitidis, Streptococcus pneumoniae, Haemophilus influenzae type b). Asplenia is predominantly due to splenectomy for either traumatic events or oncohaematological conditions. Hyposplenism can be caused by several conditions, including haematological, infectious, autoimmune and gastrointestinal disorders. Anatomical disruption of the spleen and depletion of immune cells, especially IgM memory B cells, seem to be predominantly responsible for the clinical manifestations. Early recognition of hyposplenism and proper management of asplenia are warranted to prevent overwhelming post-splenectomy infections through vaccination and antibiotic prophylaxis. Although recommendations are available, the implementation of vaccination strategies, including more effective and immunogenic vaccines, is needed. Additionally, screening programmes for early detection of hyposplenism in high-risk patients and improvement of patient education are warranted.

Review article: Follow-up of coeliac disease

Coeliac disease is a lifelong immune-mediated enteropathy with systemic features associated with increased morbidity and modestly increased mortality. Treatment with a strict gluten-free diet improves symptoms and mucosal damage but is not curative and low-level gluten intake is common despite strict attempts at adherence. Regular follow-up after diagnosis is considered best-practice however this is executed poorly in the community with the problem compounded by the paucity of data informing optimal approaches. The aim of dietary treatment is to resolve symptoms, reduce complication risk and improve quality of life. It follows that the goals of monitoring are to assess dietary adherence, monitor disease activity, assess symptoms and screen for complications. Mucosal disease remission is regarded a key measure of treatment success as healing is associated with positive health outcomes. However, persistent villous atrophy is common, even after many years of a gluten-free diet. As the clinical significance of asymptomatic enteropathy is uncertain the role for routine follow-up biopsies remains contentious. Symptomatic non-responsive coeliac disease is common and with systematic follow-up a cause is usually found. Effective models of care involving the gastroenterologist, dietitian and primary care doctor will improve the consistency of long-term management and likely translate into better patient outcomes. Identifying suitable treatment targets linked to long-term health is an important goal.

Hyposplenism and Gastrointestinal Diseases: Significance and Mechanisms

BACKGROUND

Functional hyposplenism is a recognized complication of several gastroenterological disorders, including coeliac and inflammatory bowel diseases, and is believed to contribute to the increased infection risk seen in these disorders.

SUMMARY

The mechanisms of hyposplenism are poorly understood. In this article, we review possible mechanisms underlying development of functional hyposplenism and discuss implications for its management.

KEY MESSAGES

Identifying functional hyposplenism is important, as it may permit earlier recognition and treatment of serious infections through patient education and vaccination.

Depletion of circulating IgM memory B cells predicts unfavourable outcome in COVID-19

Impaired immune responses have been hypothesised to be a possible trigger of unfavourable outcomes in coronavirus disease 2019 (COVID-19). We aimed to characterise IgM memory B cells in patients with COVID-19 admitted to an internal medicine ward in Northern Italy. Overall, 66 COVID-19 patients (mean age 74 ± 16.6 years; 29 females) were enrolled. Three patients (4.5%; 1 female) had been splenectomised and were excluded from further analyses. Fifty-five patients (87.3%) had IgM memory B cell depletion, and 18 (28.6%) died during hospitalisation (cumulative incidence rate 9.26/100 person-week; 5.8-14.7 95% CI). All patients who died had IgM memory B cell depletion. A superimposed infection was found in 6 patients (9.5%), all of them having IgM memory B cell depletion (cumulative incidence rate 3.08/100 person-week; 1.3-6.8 95% CI). At bivariable analyses, older age, sex, number of comorbidities, and peripheral blood lymphocyte count < 1500/µl were not correlated with IgM memory B cell depletion. A discrete-to-marked reduction of the B-cell compartment was also noticed in autoptic spleen specimens of two COVID-19 patients. We conclude that IgM memory B cells are commonly depleted in COVID-19 patients and this correlates with increased mortality and superimposed infections.

COVID-19 pandemic perception in adults with celiac disease: an impulse to implement the use of telemedicine

Background

Coronavirus Disease 2019 (COVID-19) causes severe complications and deaths all over the world. COVID-19 also has indirect effects from the lockdown and the possible lack of food. We aimed to evaluate the perception of this in Celiac Disease (CeD) patients who require a lifelong gluten-free diet as a therapy.

Methods

We invited by e-mail CeD adult patients from the University of Salerno (Campania, South Italy) and the University of Padua (Veneto, North Italy) to answer an ad hoc COVID-19 survey.

Results

We sent the web survey to 651 email addresses and we received 276 answers (42,4%). CeD patients did not feel more vulnerable because they had CeD (not at all 56.6%) and they did not worry much about the possible shortness of gluten-free food during the epidemic (not at all 48.5%). The most worried were the elderly patients, patients with other comorbidities and females. Finally, CeD patients were happy with remote consultations and explicitly asked to have them.

Discussion

The COVID-19 pandemic has impacted a proportion of patients with CeD; in particular, women, elderly patients, patients with other comorbidities. COVID-19, although a challenging experience from the medical and the psychological point of view, has offered an opportunity to practice, on a large-scale, a remote consultation approach for CeD healthcare.

Thromboembolic complications and cardiovascular events associated with celiac disease

Celiac disease (CD) is a chronic intestinal immune-mediated disease occurring in genetically susceptible individuals who are exposed to gluten. Although it primarily affects the small intestine, CD has been associated with a wide spectrum of extraintestinal manifestations, including thromboembolism and cardiovascular events. The risk of ischemic stroke, myocardial infarction, and thromboembolism, such as deep vein thrombosis and pulmonary embolism, is higher in patients with CD, while there is accumulating evidence that gluten-free diet in CD patients decreases the risk of these complications. The pathogenetic mechanism of increasing hypercoagulability in CD is multifactorial and involves hyperhomocysteinemia due to malabsorption of vitamins B12, B6, and folic acid; endothelial dysfunction; acceleration of atherosclerosis; chronic inflammation; thrombocytosis; and thrombophilia. Therefore, in cases of thromboembolic complications and cardiovascular disease of obscure etiology, clinicians' awareness of possible celiac disease is warranted.

Defective spleen function in autoimmune gastrointestinal disorders

Defective spleen function increases susceptibility to bacterial infections which can be prevented by vaccine prophylaxis. Splenic hypofunction can be found in a number of autoimmune disorders; however, no data are available regarding autoimmune atrophic gastritis (AAG), autoimmune enteropathy (AIE) and autoimmune liver disease (AILD). Peripheral blood samples from patients with AAG (n = 40), AIE (n = 3) and AILD (n = 40) were collected. Patients affected by autoimmune disorders already known to be associated with splenic hypofunction, i.e. coeliac disease (CD) and ulcerative colitis (UC), were included as disease controls, while splenectomised patients and healthy subjects were evaluated as positive and negative controls, respectively. Counting of erythrocytes with membrane abnormalities, i.e. pitted red cells, was used as an indicator of spleen function (normal upper limit 4%). Defective splenic function was observed in 22 of the 40 patients with AAG (55.0%), in two of the three patients with AIE (66.6%) and in 35 of the 40 patients with AILD (87.5%). As expected, in untreated CD, refractory CD and UC there was a high prevalence of hyposplenism (43.7%, 88.2% and 54.4%, respectively). Due to the high prevalence of splenic hypofunction, patients with AAG, AILD and AIE should undergo pitted red cell evaluation and, if hyposplenic, they should be candidate to vaccine prophylaxis against encapsulated bacteria.

Celiac Disease: Extraintestinal Manifestations and Associated Conditions

Celiac disease is a common form of enteropathy with frequent extraintestinal manifestations (EIM). Misrecognition of these presentations may lead to significant delays in diagnosis. Any organ may be involved, either through an immune/inflammatory phenomenon, or nutritional deficiencies. Some EIM, such as gluten ataxia, may be irreversible if left untreated, but most will improve with a gluten-free diet. Knowledge of the various EIM, as well as the associated conditions which do not improve on a gluten-free diet, will avoid delays in the diagnosis and management of celiac disease and associated manifestations.

Risk of bacterial pneumonia and pneumococcal infection in youths with celiac disease - A population-based study

OBJECTIVE

Assess the risk of hospitalizations for bacterial pneumonia or pneumococcal infections, in a cohort of young individuals with celiac disease (CD) compared to matched references.

STUDY DESIGN

The cohort consists of 213,635 individuals, born in 1989-2012 and resident in Friuli-Venezia Giulia (Italy). Through pathology reports, hospital discharge records or co-payment exemptions, we identified 1294 CD patients and 6470 reference individuals matched by gender and birth year. We considered hospital admissions for first episodes of bacterial pneumonia and pneumococcal infections. Hazard ratios (HRs) for episodes after CD diagnosis were calculated with Cox regression and odds ratios (OR) for the ones before CD diagnosis with conditional logistic regression. Further analyses were performed on unvaccinated follow-up periods.

RESULTS

14 CD patients (in 9450 person-years) and 42 references (in 48,335 person-years) experienced a first episode of bacterial pneumonia, with an increased risk among CD patients (HR 1.82; 95%CI 0.98-3.35). Risks of bacterial pneumonia were significantly increased before CD diagnosis and especially the year before CD diagnosis (OR 6.00, 95%CI 1.83-19.66). Risks of pneumococcal infections showed a non-significant increase in CD patients.

CONCLUSIONS

CD children and youth showed an increased risk of bacterial pneumonia, especially in proximity to CD diagnosis. Anti-pneumococcal vaccination should be recommended to all young CD patients.

Celiac disease: a comprehensive current review

BACKGROUND

Celiac disease remains a challenging condition because of a steady increase in knowledge tackling its pathophysiology, diagnosis, management, and possible therapeutic options.

MAIN BODY

A major milestone in the history of celiac disease was the identification of tissue transglutaminase as the autoantigen, thereby confirming the autoimmune nature of this disorder. A genetic background (HLA-DQ2/DQ8 positivity and non-HLA genes) is a mandatory determinant of the development of the disease, which occurs with the contribution of environmental factors (e.g., viral infections and dysbiosis of gut microbiota). Its prevalence in the general population is of approximately 1%, with female predominance. The disease can occur at any age, with a variety of symptoms/manifestations. This multifaceted clinical presentation leads to several phenotypes, i.e., gastrointestinal, extraintestinal, subclinical, potential, seronegative, non-responsive, and refractory. Although small intestinal biopsy remains the diagnostic 'gold standard', highly sensitive and specific serological tests, such as tissue transglutaminase, endomysial and deamidated gliadin peptide antibodies, have become gradually more important in the diagnostic work-up of celiac disease. Currently, the only treatment for celiac disease is a life-long, strict gluten-free diet leading to improvement in quality of life, ameliorating symptoms, and preventing the occurrence of refractory celiac disease, ulcerative jejunoileitis, and small intestinal adenocarcinoma and lymphoma.

CONCLUSIONS

The present review is timely and provides a thorough appraisal of various aspects characterizing celiac disease. Remaining challenges include obtaining a better understanding of still-unclear phenotypes such as slow-responsive, potential (minimal lesions) and seronegative celiac disease. The identification of alternative or complementary treatments to the gluten-free diet brings hope for patients unavoidably burdened by diet restrictions.

Pneumococcal vaccination in celiac disease

Celiac disease (CD) is an immune-mediated disorder associated with gluten exposure in genetically predisposed subjects. Areas covered: Infectious disease is one of the causes of morbidity and mortality in CD patients. Invasive streptococcus pneumoniae (pneumococcus) is a particularly dangerous morbid condition in both the general population and celiac patients. Pneumococcal vaccination is the most effective means for its prevention. Expert opinion: In CD, evaluation of spleen function should be useful to select patients who may benefit from vaccination to reduce the risk of pneumococcal disease. Different strategies could be employed: physicians could search for signs of hyposplenism on peripheral blood smear or abdominal ultrasound. However, the best strategy to identify which patients will benefit from pneumococcal vaccination has not yet been defined.

The use of an invitational letter to increase the vaccine uptake of patients with coeliac disease

Aim:

We sought to establish the impact on vaccine uptake of sending out a single appointment letter inviting patients to attend a vaccine clinic.

Background:

Coeliac disease is associated with splenic dysfunction and so patients with coeliac disease are at a higher risk of overwhelming infection. Additional vaccinations are recommended for these individuals to provide additional protection against infection.

Methods:

We retrospectively identified 54 patients with diagnosed coeliac disease, and all vaccines previously received by these patients. By comparing this to the Green Book [Department of Health (2013) Immunisation of individuals with underlying medical conditions: the green book, chapter 7, London: Department of Health. Retrieved 26 February 2019 from https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/566853/Green_Book_Chapter7.pdf], we determined the patients who were due vaccinations and the specific vaccines they were due. An invitation letter was then sent out to patients requiring further vaccinations and vaccine uptake for these patients was re-audited six months later.

Findings:

Our results show a mild increase in the total uptake of vaccines six months after the letter was sent out, from 38.6% to 49.2%.

Celiac Disease and Increased Risk of Pneumococcal Infection: A Systematic Review and Meta-Analysis

BACKGROUND

Celiac disease has been associated with hyposplenism, and multiple case reports link celiac disease and pneumococcal infections; however, increased risk of pneumococcal infection in celiac disease has not been confirmed. The purpose of this study was to conduct a systematic review to determine the risk of pneumococcal infections in celiac disease.

METHODS

Relevant studies were identified using electronic bibliographic searches of PubMed, OVID, Medline, and EMBASE (1980 to February 2017) and reviewing abstracts from major conferences in gastroenterology. Using number of events in celiac patients and referent patients, we calculated a summary relative risk of pneumococcal infections. All analyses were conducted in Comprehensive Meta-Analysis software using random-effects assumptions.

RESULTS

Of a total of 156 articles, 3, representing 3 large databases (the Swedish National Inpatient Register; the Oxford Record Linkage Study; and the English National Hospital Episode Statistics) were included. Each compared patients with celiac disease and confirmed pneumococcal infection to a specific reference group: inpatients and/or the general population. Overall, the odds of pneumococcal infection were higher among hospitalized celiac patients compared with controls (odds ratio 1.66; 95% confidence interval 1.43-1.92). There was no evidence of heterogeneity (Q[1] = 1.17, P = .56, I² = 0%).

CONCLUSIONS

Celiac disease is associated with an increased risk of pneumococcal infection. Preventive pneumococcal vaccination should be considered for those with celiac disease, with special attention to those aged 15-64 years who have not received the scheduled pneumococcal vaccination series as a child.

Splenic volume differentiates complicated and non-complicated celiac disease

BACKGROUND

Studies in small groups of patients indicated that splenic volume (SV) may be decreased in patients with celiac disease (CD), refractory CD (RCD) type II and enteropathy-associated T-cell lymphoma (EATL).

OBJECTIVE

The objective of this article is to evaluate SV in a large cohort of uncomplicated CD, RCD II and EATL patients and healthy controls.

METHODS

The retrospective cohort consisted of 77 uncomplicated CD (of whom 39 in remission), 29 RCD II, 24 EATL and 12 patients with both RCD II and EATL. The control group included 149 healthy living kidney donors. SV was determined on computed tomography.

RESULTS

The median SV in the uncomplicated CD group was significantly larger than in controls (202 cm³ (interquartile range (IQR): 154-275) versus 183 cm³ (IQR: 140-232), p = 0.02). After correction for body surface area, age and gender, the ratio of SV in uncomplicated CD versus controls was 1.28 (95% confidence interval: 1.20-1.36; p < 0.001). The median SV in RCD II patients (118 cm³ (IQR 83-181)) was smaller than the median SV in the control group (p < 0.001).

CONCLUSION

This study demonstrates large inter-individual variation in SV. SV is enlarged in uncomplicated CD. The small SV in RCD II may be of clinical relevance considering the immune-compromised status of these patients.

The risk of community-acquired pneumonia among 9803 patients with coeliac disease compared to the general population: a cohort study

BACKGROUND

Patients with coeliac disease are considered as individuals for whom pneumococcal vaccination is advocated.

AIM

To quantify the risk of community-acquired pneumonia among patients with coeliac disease, assessing whether vaccination against streptococcal pneumonia modified this risk.

METHODS

We identified all patients with coeliac disease within the Clinical Practice Research Datalink linked with English Hospital Episodes Statistics between April 1997 and March 2011 and up to 10 controls per patient with coeliac disease frequency matched in 10-year age bands. Absolute rates of community-acquired pneumonia were calculated for patients with coeliac disease compared to controls stratified by vaccination status and time of diagnosis using Cox regression in terms of adjusted hazard ratios (HR).

RESULTS

Among 9803 patients with coeliac disease and 101 755 controls, respectively, there were 179 and 1864 first community-acquired pneumonia events. Overall absolute rate of pneumonia was similar in patients with coeliac disease and controls: 3.42 and 3.12 per 1000 person-years respectively (HR 1.07, 95% CI 0.91-1.24). However, we found a 28% increased risk of pneumonia in coeliac disease unvaccinated subjects compared to unvaccinated controls (HR 1.28, 95% CI 1.02-1.60). This increased risk was limited to those younger than 65, was highest around the time of diagnosis and was maintained for more than 5 years after diagnosis. Only 26.6% underwent vaccination after their coeliac disease diagnosis.

CONCLUSIONS

Unvaccinated patients with coeliac disease under the age of 65 have an excess risk of community-acquired pneumonia that was not found in vaccinated patients with coeliac disease. As only a minority of patients with coeliac disease are being vaccinated there is a missed opportunity to intervene to protect these patients from pneumonia.

A review of guidance on immunization in persons with defective or deficient splenic function

The spleen acts as a blood filter and lymphopoietic organ. Asplenic and hyposplenic individuals are more susceptible to serious infections caused by encapsulated bacteria but they can be protected by antibiotic prophylaxis and immunizations. Recent progress in vaccinology means prophylaxis is now successful in the vast majority of serious infections with pneumococci, meningococci and Haemophilus influenzae type b responsible for the majority of cases of overwhelming sepsis in asplenic patients. Current guidelines are coherent. Physicians treating patients with conditions associated with hyposplenism are ethically obliged to immunize their patients using the vaccines currently available to protect them from largely preventable, life-threatening infections.

Hyposplenism: comparison of different methods for determining splenic function

Asplenic patients are at risk for pneumococcal sepsis. Patients with hyposplenic function, such as associated with sickle cell disease (SCD), are also at risk. However, tests to assess splenic function are either unavailable or lacking standardization. The aim of this study was to compare different methods for determining splenic function. Eighteen patients with SCD (i.e., 10 heterozygous (SC) and 8 homozygous (SS) SCD patients), and eight splenectomized patients were compared to 10 controls. All subjects underwent spleen scintigraphy, after which functional splenic volumes (FSV) were calculated. FSV was compared to immunological function and B cell-subsets, as well as phagocytic function represented by the presence of Howell Jolly bodies (HJB) and percentages of pitted red cells (PIT). Heterozygous SCD (SC) patients had increased splenic volumes, but diminished FSV, homozygous SCD (SS) patients were asplenic. Splenectomized and SS patients had a strongly reduced phagocytic and immunological function. SC patients had reduced anti-polysaccharide responses without an increase in PIT. FSV correlated significantly with phagocytic and immunological function. HJB were indicative of splenic dysfunction, HJB absence was not indicative of normal functioning splenic tissue. Although visualizing HJB is methodologically advantageous to PIT, both are valid biomarkers of splenic dysfunction. The amount of non-switched memory B cells is strongly correlated to FSV.

Celiac disease diagnosis and management: a 46-year-old woman with anemia

Celiac disease is one of the most prevalent autoimmune gastrointestinal disorders, but as the case of Ms J illustrates, diagnosis is often delayed or missed. Based on serologic studies, the prevalence of celiac disease in many populations is estimated to be approximately 1% and has been increasing steadily over the last 50 years. Evaluation for celiac disease is generally straightforward and uses commonly available serologic tests; however, the signs and symptoms of celiac disease are nonspecific and highly heterogeneous, making diagnosis difficult. Although celiac disease is often considered a mild disorder treatable with simple dietary changes, in reality celiac disease imparts considerable risks, including reduced bone mineral density, impaired quality of life, and increased overall mortality. In addition, a gluten-free diet is highly burdensome and can profoundly affect patients and their families. For these reasons, care of individuals with celiac disease requires prompt diagnosis and ongoing multidisciplinary management.

Post-splenectomy and hyposplenic states

The spleen is crucial in regulating immune homoeostasis through its ability to link innate and adaptive immunity and in protecting against infections. The impairment of splenic function is defined as hyposplenism, an acquired disorder caused by several haematological and immunological diseases. The term asplenia refers to the absence of the spleen, a condition that is rarely congenital and mostly post-surgical. Although hyposplenism and asplenia might predispose individuals to thromboembolic events, in this Review we focus on infectious complications, which are the most widely recognised consequences of these states. Because of the high mortality, the fulminant course, and the refractoriness to common treatment of overwhelming infections caused by encapsulated bacteria, prevention through vaccination and antibiotic prophylaxis is the basis of the management of patients who have had splenectomy or have hyposplenism. In this Review, we critically assess clinical and diagnostic aspects of splenic dysfunction and highlight new perspectives in the prevention of overwhelming post-splenectomy infections.

[Complications of celiac disease]

Numerous complications can occur in celiac disease, nutritional (growth failure in children, malnutrition, vitamin deficiencies), hematologic (anaemia), bone disease (osteoporosis, fracture), gynaecologic (hypo fertility), cardiovascular (coronaropathy, venous thrombosis), neurological (peripheral neuropathy), hepatic (cytolysis, cirrhosis). Celiac disease is associated with an increased risk of autoimmune diseases (type 1 diabetes, thyroiditis), and cancer (upper digestive tract, hepatocellular carcinoma, lymphoma). The main digestive complications are microscopic colitis and refractory sprue, which are resistant to gluten-free diet. It can be associated with a monoclonal proliferation of intraepithelial lymphocytes (type 2 refractory sprue), which may be considered as a cryptic lymphoma and can lead to invasive T lymphoma, which occurs in one celiac patient in 1000. Gluten-free diet protects from the occurrence of most complications and correct the over-mortality related to these complications.

Risk of morbidity in contemporary celiac disease

Celiac disease is one of the most common chronic diseases encountered in the Western world with a serological prevalence of approximately 1%. Since it is so common, much comorbidity will occur either as associations or simply by chance, or as complications of the disorder. Many of the published studies purporting to establish the frequency of these occurrences have been limited by factors such as the source and number of patients considered, choice of control groups and ascertainment bias. Recent epidemiological studies have attempted to minimize these sources of error and provide more reliable information. Autoimmune diseases constitute clinically important associations, of which Type 1 diabetes mellitus and thyroid disorders are the most important. Several liver disorders, including primary biliary cirrhosis and primary sclerosing cholangitis, are also associated. The frequency of malignant complications of celiac disease is much lower than earlier studies have indicated, with lymphoma increased by approximately fivefold and the absolute number of tumors is small. The increase in fracture risk in celiac disease is only modest. Although neurological and psychiatric conditions affect celiac patients, no disorder specifically associated with celiac disease has been identified. Reproductive problems have been overexaggerated. It is important that these co-morbidities are recognized because if not, symptoms will be falsely attributed to deliberate or inadvertent ingestion of gluten, rather than prompt a search for a second diagnosis. Furthermore, in a patient with an established diagnosis that is considered falsely to account for the whole clinical picture, celiac disease is likely to remain undetected.

Assessment of splenic function

Hyposplenic patients are at risk of overwhelming post-splenectomy infection (OPSI), which carries mortality of up to 70%. Therefore, preventive measures are warranted. However, patients with diminished splenic function are difficult to identify. In this review we discuss immunological, haematological and scintigraphic parameters that can be used to measure splenic function. IgM memory B cells are a potential parameter for assessing splenic function; however, more studies are necessary for its validation. Detection of Howell-Jolly bodies does not reflect splenic function accurately, whereas determining the percentage of pitted erythrocytes is a well-evaluated method and seems a good first-line investigation for assessing splenic function. When assessing spleen function, (99m)Tc-labelled, heat-altered, autologous erythrocyte scintigraphy with multimodality single photon emission computed tomography (SPECT)-CT technology is the best approach, as all facets of splenic function are evaluated. In conclusion, although scintigraphic methods are most reliable, they are not suitable for screening large populations. We therefore recommend using the percentage of pitted erythrocytes, albeit suboptimal, as a first-line investigation and subsequently confirming abnormal readings by means of scintigraphy. More studies evaluating the value of potentially new markers are needed.

Coeliac disease

Coeliac disease is a chronic inflammatory disorder of the small bowel induced in genetically susceptible people by the irritant gluten and possibly other environmental cofactors. The disorder is characterised by a diverse clinical heterogeneity that ranges from asymptomatic to severely symptomatic, and it manifests with frank malabsorption, an increased morbidity attributable to the frequent association with autoimmune disorders and increased mortality resulting from the emergence of T-cell clonal proliferations that predispose the patient to enteropathy-type T-cell lymphoma. Our understanding of the molecular basis for this disorder has improved and enabled the identification of targets for new therapies, although a strict gluten-free diet remains the mainstay of safe and effective treatment. In this Seminar we critically reassess the clinical and diagnostic aspects of this disease and new perspectives in its pathogenesis and treatment.

Celiac Disease in the 21st Century: Issues of Under-and Over-Diagnosis

Until the 1960s celiac disease (CD) or sprue was considered a pediatric disease that was rarely diagnosed in adulthood. Thanks to greater awareness of the disease and the availability of improved diagnostic tools (above all, sophisticated endoscopic techniques and the development of reliable serological markers), the prevalence of CD in Western countries has been increasing steadily, and it is now recognized as a common disorder, even in adults. However, many cases of this disease still go undiagnosed, especially among the elderly and in patients with atypical clinical presentations (which are by no means uncommon). On the other hand, the frequency of unfounded diagnoses of CD is also on the rise. This reflects a tendency toward exclusively symptomatic diagnosis as well as the growing use of invalidated tests for CD (e.g., the cytotoxic test, the sublingual or subcutaneous provocation/neutralization test, etc.). As a result, public healthcare spending is being increased in several countries (Italy included) by the growing number of prescriptions for gluten-free diets. This editorial discusses the problems of under- and over-diagnosis of CD and provides an algorithm for management of suspected cases designed to minimize both problems with particular importance to morphologic aspects of small bowel (also in electron microscopy), in basal conditions or in gluten-free diets.

Systematic review: The evidence base for long-term management of coeliac disease

BACKGROUND

While gluten-free diet is an effective treatment for coeliac disease, the need for and goals of long-term management of patients are poorly defined.

AIM

To review systematically the complications and associations of coeliac disease, to identify potential risk factors, to define ways of assessing risk factors and to provide a strategy for management.

METHODS

Review of medical literature from 1975.

RESULTS

There is an increasing list of potential complications and/or conditions associated with coeliac disease, in particular, autoimmune disease, malignancy and bone disease. Risk factors that may predict or influence long-term outcomes include genetic susceptibility, environmental factors predominantly gluten ingestion, persistent small intestinal inflammation/injury and nutritional deficiencies. Genotyping of patients is yet to have an established clinical role in long-term management. Assessment of adherence to the gluten-free diet largely relies upon skilled dietary history, but the ultimate test is duodenal histopathology, which is the only currently established means of assessing healing. Symptoms, serology or other non-invasive means are poor predictors of healing and the likelihood of complications.

CONCLUSION

Evidence (albeit limited) that adherence to a gluten-free diet and mucosal healing prevent and/or ameliorate complications indicates that a planned long-term strategy for follow-up is essential.

Cystic lymphangioma of the mesentery and hyposplenism in celiac disease

Celiac disease is characterized by intestinal inflammation and mucosal atrophy that improves on a gluten-free diet. Delayed diagnosis can result in diet-refractory disease known as refractory sprue, which is linked to other disorders (intestinal lymphoma, ulcerative jejunoileitis, mesenteric lymph-node cavitation, collagenous sprue, malignancy) and carries a poor prognosis. Here we report the case of a young woman diagnosed with Marsh stage 3C celiac disease with intestinal occlusion due to intra-abdominal cystic lymphangioma mimicking mesenteric lymph-node cavitation, and hyposplenism. Despite a number of prognostically negative features, the disease has been managed successfully for the past 2 years with a gluten-free diet. The pathogenesis, prognosis and therapeutic implications are discussed.

Hematologic manifestations of celiac disease

Celiac disease is a common systemic disorder that can have multiple hematologic manifestations. Patients with celiac disease may present to hematologists for evaluation of various hematologic problems prior to receiving a diagnosis of celiac disease. Anemia secondary to malabsorption of iron, folic acid, and/or vitamin B12 is a common complication of celiac disease and many patients have anemia at the time of diagnosis. Celiac disease may also be associated with thrombocytosis, thrombocytopenia, leukopenia, venous thromboembolism, hyposplenism, and IgA deficiency. Patients with celiac disease are at increased risk of being diagnosed with lymphoma, especially of the T-cell type. The risk is highest for enteropathy-type T-cell lymphoma (ETL) and B-cell lymphoma of the gut, but extraintestinal lymphomas can also be seen. ETL is an aggressive disease with poor prognosis, but strict adherence to a gluten-free diet may prevent its occurrence.

Effect of liver transplantation on tuftsin activity and phagocytic activity of neutrophil granulocytes in patients with liver cirrhosis

BACKGROUND

Tuftsin activity (TA) is reduced in cirrhosis. This contributes to the defective phagocytic activity (PA) of neutrophil granulocytes and is related to the impairment of splenic function. Orthotopic liver transplantation (OLT) cures cirrhosis and might restore TA. This study was aimed at determining if OLT restores TA and PA.

METHODS

We measured in 9 cirrhotic patients, before and after successful OLT, TA by a bioassay and PA by chemiluminescence in which neutrophils of the patient were tested with both autologous (PA1) and pooled sera from healthy subjects (PA2). Splenic function was assayed by the pitted red cell count.

RESULTS

Before OLT, TA was reduced in 7 patients, and PA1 in all the patients. Pitted cell count was elevated in all the patients. After OLT (median 39 months; range 21-49), TA improved in all cases [median: from 8% (5-16%) to 20% (9-22%), p < 0.008], normalizing in 5 out of the 7 patients with low values. PA1 improved in all the patients [from 102 cpm (65-128 cpm) to 235 cpm (78-280 cpm), p < 0.008], normalizing in 5. Pitted red count decreased in 7 patients and normalized in 3 [from 3.3% (2.1-6.0%) to 2.4% (1.4-2.8%), p < 0.021]. Platelet count [from 55 x 10(3) (30-100) to 185 x 10(3) (93-286), p < 0.008] and leucocyte count [from 3.60 x 10(3) (1.81-5.23) to 5.53 x 10(3) (3.31-6.71), p < 0.008] also improved.

CONCLUSIONS

OLT improves TA and PA of cirrhotic patients. This effect is associated with an improvement of both functional hyposplenism and haematological hypersplenism. The restoration of natural defences against infections may mitigate the adverse effect of immunosuppressive treatment.

Apoptosis and peripheral blood lymphocyte depletion in coeliac disease

In coeliac disease (CD) immunological abnormalities are not confined to the small bowel and it has been suggested that changes in peripheral blood lymphocytes (PBL), such as lymphopenia and increased T-cell activation, may predispose to malignant or autoimmune complications of this condition. In the light of the recent findings about the Fas-Fas ligand (FasL) system in regulating lymphocyte homeostasis, the aim of the present study was to investigate peripheral lymphocyte Fas-mediated apoptosis in CD to establish whether the homeostatic role of apoptosis in peripheral T-cell selection is maintained. Moreover, because a soluble form of Fas has been described to be functionally implicated in the Fas signalling system, suggesting a relationship between some disorders and soluble Fas function, we measured levels of soluble Fas in sera of coeliac patients and analysed the relationship between these levels and the proportions of apoptotic and Fas(+) PBL to further explore the function of the Fas-FasL pathway in this condition. Finally, we evaluated whether the increased prevalence of anticardiolipin antibodies, recently described in CD, could be related to PBL apoptosis in this condition. We demonstrated an increased apoptosis and higher levels of Fas and FasL expression in PBL isolated from untreated coeliac patients when compared to treated coeliac patients and controls. In addition, low levels of soluble Fas and a significant positive correlation between anticardiolipin antibodies and PBL apoptosis were found in untreated CD. Then, our results showed an increased susceptibility of PBL to undergo Fas-mediated apoptosis in active CD. This increased apoptosis could be responsible for both lymphopenia and immunogenic exposure of phospholipids with subsequent production of autoantibodies.

Celiac disease in older people

In recent years, there has been increasing recognition that the classical textbook presentation of celiac disease with a malabsorption syndrome and a flat jejunal mucosa is only part of a broad spectrum of clinical and histological features associated with gluten sensitivity. Diagnosis of this treatable condition is often delayed or missed because of a failure to appreciate that celiac disease can present at any age and that symptoms are often subtle and not clearly related to gastrointestinal disease. Nonspecific symptoms and nutritional deficiencies are especially common in older patients and may not always be investigated thoroughly. Use of serological screening tests has improved ease of detection of celiac disease in patients without classical symptoms.