Acute graft-versus-host disease is more prevalent and severe in the lower than the upper gastrointestinal tract

PET assessment of acute gastrointestinal graft versus host disease

Acute gastrointestinal graft versus host disease (GI-GVHD) is a common complication following allogeneic haematopoietic cell transplantation (HCT), and is characterised by severe morbidity, frequent treatment-refractoriness, and high mortality. Early, accurate identification of GI-GVHD could allow for therapeutic interventions to ameliorate its severity, improve response rates and survival; however, standard endoscopic biopsy is inadequately informative in terms of diagnostic sensitivity or outcome prediction. In an era where rapid technological and laboratory advances have dramatically expanded our understanding of GI-GVHD biology and potential therapeutic targets, there is substantial scope for novel investigations that can precisely guide GI-GVHD management. In particular, the combination of tissue-based biomarker assessment (plasma cytokines, faecal microbiome) and molecular imaging by positron emission tomography (PET) offers the potential for non-invasive, real-time in vivo assessment of donor:recipient immune activity within the GI tract for GI-GVHD prediction or diagnosis. In this article, we review the evidence regarding GI-GVHD diagnosis, and examine the potential roles and translational opportunities posed by these novel diagnostic tools, with a focus on the evolving role of PET.

Round-Robin test for the histological diagnosis of acute colonic Graft-versus-Host disease validating established histological criteria and grading systems

Histomorpholgy is one of the mainstays of acute Graft-versus-host disease (GvHD) diagnosis. However, concerns about reproducibility and the most appropriate grading system question its usefulness. Our aim was to assess histomorphological parameters and previously reported grading systems for GvHD regarding reproducibility and validity. Moreover, we propose that sum scores, derived by combining separately scored morphological parameters into a total score, might provide a simplified but equally effective means to grade GvHD. A total of 123 colon biopsies were assessed across four pathologists for intestinal GvHD using a Round-Robin test and results were correlated with clinical findings. Interobserver reproducibility was high for histological parameters that were evaluated as indicators of acute GvHD. Published grading systems were moderately reproducible (ICC 0.679-0.769) while simplified sum scores, in comparison, showed better interrater reliability (ICC 0.818-0.896). All grading systems and sum scores were associated with clinical signs of GvHD and in part with therapy response and survival. However, they were not able to stratify patients according to the clinical severity of GvHD. In a hot-spot analysis 1 crypt apoptotic body (CAB) in 10 crypts was a reasonable cut-off value for minimal diagnostic criteria of GvHD. In conclusion, histology can contribute to the diagnosis of GvHD and is reproducible. Published grading systems are able to reflect clinical findings as are simplified sum scores, which showed improved reproducibility and might be easier to handle as they are based on adding up histological parameters rather than transferring histological findings into a separate grading system. Sum scores will have to be further tested in a prospective setting.

[Immunopathology of the small intestine]

The gastrointestinal tract is the site of exciting immunological interactions between the epithelium and the mucosa-associated lymphoid tissue, leading to the immune response to food and microbial antigens in the digestive lumen. The objective of this review is to present the main dysimmune pathologies of the digestive tract leading to an enteropathy. As examples, we describe celiac and non-celiac enteropathies to clarify a florid diagnostic framework, by identifying a spectrum of elementary lesions, which must be confronted with the clinico biological context of the patient to orient the diagnosis. The microscopic lesions observed are most often non-specific and may be encountered in several diagnostic settings. Moreover, it is a set of elementary lesions in each clinical context that will orient the diagnostic framework. Celiac disease is the main etiology of enteropathy with villous atrophy, its diagnosis is multidisciplinary and there are many differential diagnoses. We will discuss celiac disease lymphomatous complications as enteropathy associated T-cell lymphoma including refractory sprue type 2. We will then present the non-celiac enteropathies. Among these, enteropathies of unknown etiology may be associated with a primary immune deficiency that may be reflected by florid lymphoid hyperplasia of the gastrointestinal tract and/or be associated with an infectious etiology that should also be constantly sought. Finally, we will discuss of induced enteropathy by new immunomodulatory treatments.

An investigation of the diagnostic, predictive, and prognostic impacts of three colonic biopsy grading systems for acute graft versus host disease

Acute graft versus host disease (aGvHD) is an important, life-threatening complication after allogeneic hematopoietic stem cell transplantation (alloHSCT). To investigate the value of multiple simultaneous colon biopsies in improving diagnostic accuracy in patients with aGvHD, we retrospectively analyzed 157 patients after alloHSCT. The biopsies were evaluated individually using three established histological grading systems (Lerner, Sale, and Melson). The maximum, minimum, median, and mean histological aGvHD grades were calculated for each patient, and the results were correlated with the Glucksberg grade of clinical manifestation of GvHD, steroid therapy status, and outcome. We found that multiple colon biopsies enhanced diagnostic sensitivity. Moreover, higher histological grades correlated with steroid therapy initiation and refractoriness; the latter particularly occurred when advanced damage was present in all samples and healthy colon mucosa was reduced or absent. On multivariate analysis, the minimal Lerner and Glucksberg grades for intestinal aGvHD were significantly associated with steroid treatment failure. Ninety-nine patients died. The median survival was 285 days after the biopsies were taken. Fifteen patients died from relapse of their underling disorder and 84 from other causes, mostly infection (53 patients) and GvHD (14 patients). Multivariate analysis revealed a significant association between none-relapse mortality and the mean Lerner grade, minimum Melson grade, Glucksberg organ stage, and platelet counts. Thus, we found the Lerner system to be superior to the other grading methods in most instances and histologic evaluation of multiple simultaneously obtained biopsies from the colon to result in a higher diagnostic yield, which helps plan systemic steroid treatment while predicting treatment response and outcome.

Evaluation of the lower histologic threshold for gastric graft versus host disease

Data regarding the lower diagnostic threshold for gastric graft-versus-host disease is lacking. The aim of this study was to review a cohort of gastric biopsies taken to evaluate for graft-versus-host disease, and to correlate histologic findings with clinical and endoscopic evidence of graft-versus-host disease as well as biopsy findings from other locations to define a lower diagnostic threshold for gastric graft-versus-host disease. Gastric biopsies were evaluated for the maximum number of apoptotic bodies per 10 contiguous gastric pits, presence of ≥1 apoptotic body per biopsy (NIH criteria), and presence of gastric pit dropout and/or ulceration. To evaluate histologic specificity, sixty gastric biopsies from non-stem cell transplant patients were selected as a control group. Clinical information was collected from chart review. The study group consisted of 65 gastric biopsies from 52 stem cell transplant patients. The mean apoptotic count per 10 contiguous gastric pits for stem cell transplant biopsies was 1.8 (range 0-8) and for control cases 1.0 (range 0-5). Nineteen stem cell transplant biopsies (29%) had ≥1 apoptotic body per biopsy and only a single case had >6 apoptotic bodies per 10 contiguous gastric pits. When the NIH guidelines were combined with presence of at least two apoptotic bodies per 10 contiguous gastric pits, this cutoff point was significantly associated with treatment for graft-versus-host disease (OR = 9.4, 95% CI = 1.7-176.7, p = 0.04) and evidence of extraintestinal graft-versus-host disease (OR = 3.2, 95% CI = 1.1-10.7, p = 0.04). The diagnostic specificity for our proposed cutoff value is 94%. We present criteria for the lower diagnostic threshold of gastric graft-versus-host disease, which uses a lower apoptotic cutoff value than has been utilized in colonic biopsies. Although sensitivity remains a challenge for gastric graft-versus-host disease biopsies, this newly proposed cutoff provides higher specificity than NIH guidelines alone and better correlates with clinical evidence of graft-versus-host disease.

Current approach to early gastrointestinal and liver complications of hematopoietic stem cell transplantation

The gastrointestinal (GI) system is one of the most commonly affected sites during a hematopoietic stem cell transplantation (HSCT) due to toxicities of preparative regimens, the accompanying immunodeficiency, and organ damage caused by graft versus host disease. In this review, we focus on early GI and liver complications following autologous (auto-) and allogeneic (allo-) HSCT and clarify both the risk factors and therapeutic strategies. Early GI and liver complications associated with HSCT remain challenging issues. Despite the improvements in this field during the last decade, treatments for these complications still place a significant burden on both patients and the physicians treating these patients. GI and liver complications remain some of the causes of mortality associated with HSCT. For practicing hematologists, oncologists, and gastroenterologists in this field, the awareness and early diagnosis of the GI complications remain important factors to obtain optimal outcomes in this patient population.

Site specific diagnostic yield of endoscopic biopsies in Gastrointestinal Graft-versus-Host Disease: A tertiary care Center experience

BACKGROUND

Gastrointestinal (GI) graft versus host disease (GVHD) occurs in up to 40% of patients undergoing allogenic hematopoietic stem cell transplantation (HSCT). However, the optimal endoscopic approach is still unclear and the area of the GI tract with the highest diagnostic yield is still a topic of debate.

OBJECTIVE

We compared the diagnostic yield of different anatomic site biopsies in the diagnosis of GI GVHD and assessed the correlation of endoscopic findings with histopathology.

METHODS

All cases of biopsy proven GI GVHD were obtained from pathology database AUBMC between 1/1/2005 and 31/8/2017. We retrospectively analyzed the demographical, clinical and endoscopic data.

RESULTS

Nineteen patients were diagnosed with GI GVHD over 17.6 years. The most common presenting symptom was severe diarrhea (18 patients, 94.7%). Combining upper endoscopy and sigmoidoscopy with biopsies had the highest diagnostic yield of 90% in diagnosing GI GVHD compared to 63.6%, 78.6% and 77.8% for upper endoscopy, sigmoidoscopy and colonoscopy respectively. In macroscopically normal mucosa, the recto-sigmoid and duodenal biopsies had the highest diagnostic yield (75%). As for the macroscopically abnormal mucosa, the highest yield was for the recto-sigmoid biopsies (100%) in lower endoscopy and duodenal biopsies in the upper endoscopy (60%).

CONCLUSION

In a patient suspected to have GI GVHD, the best endoscopic approach is the combination of upper endoscopy and flexible sigmoidoscopy with biopsies of normal as well as abnormal mucosa. It should be emphasized that normal mucosa be biopsied especially in the duodenum and recto-sigmoid for a better diagnostic yield.

Gastrointestinal Biopsies for Evaluation of Acute Graft-Versus-Host Disease in Allogeneic Hematopoietic Stem Cell Transplant Patients

Graft-versus-host disease (GVHD) is the major complication post hematopoeitic stem cell transplantation (HSCT) causing significant morbidity and mortality. Colonic biopsies were performed in 25 post HSCT patients presenting the diarrhea for diagnosis of acute graft versus host disease (A-GVHD). The present study was undertaken to evaluate and illustrate histomorphological features of A-GVHD in GI biopsies and to grade them. Histopathological features of gastrointestinal biopsies from 25 allogeneic HSCT patients having clinical suspicion of A-GVHD were evaluated and compared with colonic biopsies from negative controls. A-GVHD was observed in 17 cases, CMV colitis was present in 3 cases and one case had herpes simplex infection diagnosed in conjunction with serological findings. A-GVHD was graded as grade 1 and 2 in 10 cases and grade 3 and 4 in 7 cases. Apoptosis of crypt epithelial cells was the cardinal feature for diagnosis. Grade 1 and grade 2 A-GVHD cases showed crypt apoptosis in all cases as well as pericryptal apoptosis in lamina propria in many cases. Occasional crypt loss was seen in grade 2 GVHD. Inflammatory infiltrate was composed of lymphocytes and plasma cells. Neutrophils were inconspicuous. Grade 3 and grade 4 A-GVHD cases showed contiguous areas of multiple crypt loss and ulceration with inflammatory infiltrate predominantly composed of lymphocytes and plasma cells, but neutrophils were more prominent than in grade 1 and 2 A-GVHD. Apoptosis of crypt epithelial cells was present in all grade 3 &4 cases except one case. CMV cases were diagnosed by CMV inclusions and IHC stain. Several factors including drug-induced side effects and infections can cause difficulty in histologic interpretation of gastrointestinal biopsies for GVHD. Proper histomorphological interpretation of intestinal A-GVHD is critical for clinical management. A-GVHD is treated with immunosuppression which may worsen infective condition, if present.

Choice of Endoscopic Procedure in Children With Clinically Suspected Gastrointestinal Graft-versus-host Disease

OBJECTIVES

Gastrointestinal graft-versus-host disease (GI-GVHD) is a potentially life-threatening complication after hematopoietic stem cell transplantation. Symptoms indicating GI-GVHD motivates endoscopy with biopsy sampling and histopathological confirmation. Optimal extent of endoscopy in children is, however, presently unknown. Therefore, we aimed to evaluate whether biopsies from the rectosigmoid area versus the rest of the colon/ileocolon with or without biopsies from simultaneous upper endoscopy, were equally reliable for detection of GI-GVHD and relevant differential diagnoses.

METHODS

Retrospective multicenter study based on histopathological re-evaluation of biopsies and hospital record data, collected from children with suspected GI-GVHD.

RESULTS

Forty-four children with 51 endoscopic occasions (81 procedures) were included. Thirty-nine of 51 (76.5%) were diagnosed as GI-GVHD, 14 (27.4%) received a differential diagnosis and 7 (13.7%) had normal histology findings. Comorbidity, that is, simultaneous detection of a differential diagnosis and GI-GVHD, was observed in 9 (23.1%) cases. Cytomegalovirus infection was the most frequent differential diagnosis, 6 of 7 were detected in biopsies from rectosigmoid and esophagogastroduodenal areas. Sensitivity for detection of GI-GVHD in biopsies collected from rectosigmoid-ileocolonic-, rectosigmoid-, or esophagogastroduodenal areas were 97.4%, 84.6%, 83.3%, respectively, and 97.4% when the latter 2 were merged. The difference, nondetected GI-GVHD in the rectosigmoid area versus detected elsewhere in the GI tract, was statistically significant (P = 0.03).

CONCLUSIONS

Biopsies collected from the rectosigmoid area solely were not optimal for detection of pediatric GI-GVHD. When biopsy sampling from rectosigmoid and upper GI tract areas was combined, the sensitivity for GI-GVHD was, however, equally high as for ileocolonoscopy or full upper and lower endoscopy.

Effective and less invasive diagnostic strategy for gastrointestinal GVHD

BACKGROUND AND STUDY AIMS

 Rectosigmoidoscopy with biopsy has been regarded to be a useful procedure to diagnose gastrointestinal graft-versus-host disease (GVHD). However, little is known about the specific colonoscopic features of gastrointestinal GVHD. In this study, we focused on the 4 unique colonoscopic findings - orange peel appearance, spotty redness, small mucosal sloughing, and diffuse mucosal defect - which are possible specific findings of gastrointestinal GVHD. We aimed to estimate the usefulness of these four unique colonoscopic findings in the rectosigmoid portion to diagnose gastrointestinal GVHD.

PATIENTS AND METHODS

 Seventy patients who were histologically diagnosed with gastrointestinal GVHD at our institute were retrospectively enrolled. Colonoscopic findings were reviewed, focusing on the four characteristic findings. The percentage of the positive cases for the characteristic findings was calculated. The final scoping portion and the number of cases showing any of the four characteristic findings in the rectosigmoid portion were also evaluated. The relationships between biopsy sites and the histological findings were also evaluated.

RESULTS

 Orange peel appearance was observed in 66 cases (94.3 %). Spotty redness was observed in 45 cases (64.3 %). Small mucosal sloughing was observed in 49 cases (70.0 %). Diffuse mucosal defect was observed in six cases (8.6 %). The number of cases that were concurrently positive for one, two, and three findings were 16 (20.8 %), 20 (26.0 %), and 34 (48.6 %), respectively. Fifty-eight cases (82.9 %) were investigated up to the rectosigmoid portion, and 12 (17.1 %) were investigated beyond the sigmoid colon. All of the cases showed at least 1 of the 4 characteristics in the rectosigmoid portion. The percentage of crypt apoptosis in the biopsy specimen from orange peel appearance, spotty redness, small mucosal sloughing, and diffuse mucosal defect were 87.5 %, 83.3 %, 87.2 %, and 88.9 %, respectively.

CONCLUSION

 Orange peel appearance, spotty redness, small mucosal sloughing, and diffuse mucosal defect are the characteristic colonoscopic findings useful for diagnosis of gastrointestinal GVHD. These findings are frequently observed in the rectosigmoid portion. The histological detection rates for crypt cell apoptosis from these findings are high. Identifying the four characteristic findings on rectosigmoidoscopy and taking biopsies from these areas could be essential for the diagnostic strategy for gastrointestinal GVHD.

Acute graft-versus-host disease of the gut: considerations for the gastroenterologist

Haematopoietic stem cell transplantation (HSCT) is central to the management of many haematological disorders. A frequent complication of HSCT is acute graft-versus-host disease (GVHD), a condition in which immune cells from the donor attack healthy recipient tissues. The gastrointestinal system is among the most common sites affected by acute GVHD, and severe manifestations of acute GVHD of the gut portends a poor prognosis in patients after HSCT. Acute GVHD of the gastrointestinal tract presents both diagnostic and therapeutic challenges. Although the clinical manifestations are nonspecific and overlap with those of infection and drug toxicity, diagnosis is ultimately based on clinical criteria. As reliable serum biomarkers have not yet been validated outside of clinical trials, endoscopic and histopathological evaluation continue to be utilized in diagnosis. Once a diagnosis of gastrointestinal acute GVHD is established, therapy with systemic corticosteroids is typically initiated, and non-responders can be treated with a wide range of second-line therapies. In addition to treating the underlying disease, the management of complications including profuse diarrhoea, severe malnutrition and gastrointestinal bleeding is paramount. In this Review, we discuss strategies for the diagnosis and management of acute GVHD of the gastrointestinal tract as they pertain to the practising gastroenterologist.

Histologic Grade 1 Is Associated With Increased Nonrelapsed Mortality in Lower Gastrointestinal Graft Versus Host Disease

Histologic confirmation is considered a standard practice to diagnose gastrointestinal graft versus host disease (GI GVHD) and is often used in making treatment decisions. A histologic grade is often determined in cases that are diagnosed with GI GVHD. Although extensive crypt loss (histologic grade 4) is associated with high nonrelapse mortality (NRM), the prognostic value for the more common grade 1 is poorly understood. As clinical decisions are made on the degree of histologic evidence, it is important to establish its prognostic significance. Therefore, we evaluated 309 patients who underwent endoscopic biopsy for suspected GI GVHD within 6 months posttransplant between 2009 and 2012. The presence of histologic grade 1 was associated with increased NRM (hazard ratio=2.7, P=0.02) when compared with one of negative biopsy in patients with lower but not isolated upper GI GVHD. Multivariate competing-risk regression analysis confirmed the independent impact of histologic grade 1 in patients with early clinical stages of lower GI GVHD (stage 0 to 2) (hazard ratio=2.7, P=0.044). When compared with advanced histologic grades, histologic grade 1 did not lessen the adverse outcome for patients with advanced lower GI GVHD (stage 3 to 4) (cumulative incidence NRM of 84%). In conclusion, the presence of histologic grade 1 is associated with increased NRM in patients presenting with lower GI GVHD (stages 0 to 2) and is sufficient evidence for decision to initiate therapy. At the same time, histologic grade 1 does not lessen the markedly adverse impact of advanced lower GI GVHD (stage 3 to 4) and is not synonymous with "mild" GVHD.

Graft-versus-Host Disease of the Gut: A Histologic Activity Grading System and Validation

The pathologic interpretation of gut biopsies in hematopoietic cell transplant recipients to assess graft-versus-host disease (GVHD) is well accepted and supplements clinical and endoscopic findings. However, the histologic activity grading of GVHD is controversial, with attempts to predict prognosis or response to treatment largely unsuccessful. GVHD is being diagnosed earlier in its course, raising the possibility that the pathologic grading system can be profitably modified. We developed a histologic activity grading system designed to replace the commonly used modified Lerner grading systems. Our system stratifies the low-level Lerner grade I category into 4 activity grade categories, based on the average frequency of apoptotic cells. The results are expressed as ordinal categories: GVHD of minimal, mild, moderate, severe histologic activity, or severe histologic activity with destruction (activity grades 1 to 5). In a retrospective study, we studied 87 consecutive cases with 201 post-transplantation specimens (median, 48 days; range, 18 to 1479 days) of stomach, duodenum, and colorectum, which had been activity graded at the time of the original diagnosis. Most of the biopsies diagnosed as GVHD were low grade-minimal (11%) or mild (71%) histologic activity. We hypothesized that the higher activity grades would be associated with more therapeutic intervention. The odds of increased therapy in the combined all-site specimens were increased as activity grade increased (odds ratio, 2.9 [95% confidence interval {CI}, 1.9 to 4.5]; P = < .0001). Thus, our grading system was validated. To investigate whether the activity grade was associated with therapy within the formerly undivided Lerner grade I category, the analysis was restricted to these 174 all-site specimens. The validation result was similar (odds ratio, 3.1 [95% CI, 1.3 to 7.2]; P = .009). This result interestingly suggests that there is useful information hidden in the Lerner grade I category, which could potentially guide immediately actionable treatment decisions. This histologic activity grade system has been in use at our institution for over 2 years with good acceptance.

Sensitivities of Biopsy Sites in the Endoscopic Evaluation of Graft-Versus-Host Disease: Retrospective Review from a Tertiary Center

BACKGROUND

Graft-versus-host disease (GVHD) is a complication of hematopoietic stem cell transplantation that frequently affects the gastrointestinal (GI) tract. The best biopsy sites to establish the diagnosis have not been clearly established.

AIMS

To determine the best sites for obtaining biopsies in evaluating GI GVHD.

METHODS

All cases of biopsy-proven GI GVHD (GVHD+) were isolated from a pathology database over a 2-year period at a single tertiary center (n = 46). Demographic, clinical, and endoscopic data were extracted. For comparison, 46 consecutive GVHD-negative cases (GVHD-) were obtained. Sensitivities in diagnosing GVHD in the upper and lower GI tract were calculated.

RESULTS

In the GVHD- group, they were commonly investigated with an esophagogastroduodenoscopy (EGD) (60 vs. 22 % in the GVHD+ group, p < 0.01), while a colonoscopy (CLN) was commonly performed in the GVHD+ group (33 vs. 12 %, p = 0.02). Among the GVHD + patients, for EGDs, the sensitivity was highest for duodenal biopsies at 89 %. For flexible sigmoidoscopies (FSs) and CLNs, the sensitivities among all sites were similar (85 % agreement, kappa 0.58, p = 0.01). There were no cases in which GVHD was diagnosed in the right side of the colon without a positive biopsy in the left side of the colon.

CONCLUSIONS

In this cohort of GI GVHD patients, duodenum biopsies produced the highest yield in diagnosing GVHD when compared to other sites of the upper GI tract. Sensitivities were similar among all sites on lower endoscopies, suggesting that a FS is sufficient for diagnosing GVHD in suspected patients with diarrhea.