Diagnostic phrasing is independently correlated with the decision to treat for graft-versus-host disease: retrospective review of colon biopsies with rare apoptosis

Gastrointestinal Biopsies in the Patient Post-Stem Cell Transplant: An Approach to Diagnosis

Graft-versus-host disease (GVHD) is a major complication of hematopoietic stem cell transplantation (SCT), leading to a significant morbidity and mortality. Histologically, gastrointestinal GVHD is characterized by crypt apoptosis and dropout. However, similar histologic features can also be seen in drug-induced injury and opportunistic infection. Knowledge of the timing of biopsy, patient medications, evidence of infection, and presence of GVHD at other organ sites can aid in the correct diagnosis and subsequent management of these patients. This review focuses on the pathologic differential diagnosis of apoptosis in gastrointestinal biopsies obtained from SCT patients.

Clinicopathologic characterization of gallbladder graft-versus-host disease in the pediatric population

Graft-versus-host disease (GVHD) is a common and important complication of allogenic hematopoietic cell transplantation. The cardinal histologic feature of GVHD in the gastrointestinal tract is the presence of apoptotic bodies. To date, no study has evaluated the pathologic characteristics of gallbladder GVHD (GB-GVHD). In this study, we sought to describe their clinicopathologic features in a cohort of pediatric patients and compared them to a control group composed of 10 and 15 recent cases of acute and chronic cholecystitis, respectively. A total of 6 GB-GVHD cases were included, 5 cholecystectomies and 1 autopsy case(s), presenting in 2 boys and 4 girls, with a mean age of 6.7 years (1.5-18.6). The median days post-transplant to presentation was 261 (40-699), and all cases had GVHD involving other organs. GB-GVHD compared to the control groups was significantly associated with a younger age (P = .019), presence of apoptotic bodies and higher number of apoptotic bodies in 10 continuous mucosal folds and in 100 and 500 epithelial cells (all P < .001), and increased number of intraepithelial lymphocytes per 100 epithelial cells (P < .001). All patients were treated for GVHD with half of them achieving treatment response. Besides the autopsy case, all patients are alive with a median follow-up time of 45 months (4-212). The cause of death for the autopsy case was sepsis due to Pseudomonas aeruginosa. In our experience, the presence of both increased apoptotic bodies and intraepithelial lymphocytes in the gallbladder of hematopoietic cell transplantation patients should raise concern for GB-GVHD.

Multi-institutional development and validation of a novel histologic grading system for colonic graft-versus-host disease

Graft-versus-host disease (GVHD) remains a major complication for patients who have undergone hematopoietic stem cell transplantation. The Lerner system is the most widely used histologic grading score for gastrointestinal GVHD but its clinic utility is debated. The aim of our study was to develop a novel histologic grading system for gastrointestinal GVHD that incorporates independent evaluation of both apoptotic counts and crypt destruction. Colonic biopsies taken to assess for GVHD were retrospectively assessed for: Crypt damage (No crypt dropout or ulceration-0; crypt dropout without ulceration-1; ulceration-2) and crypt apoptotic counts (No apoptosis-0; 1-6 apoptotic bodies per 10 contiguous crypts-1; >6apoptotic bodies per 10 contiguous crypts-2). The two scores were added together to get an overall grade (0-4). Alternative apoptotic cutoff points were examined. An apoptotic cutoff of >9 apoptotic bodies per 10 contiguous crypts marginally improved the area under the curve (AUC), but the AUCs from the resulting novel grade calculations were not significantly different (p = 0.10). Lerner grading was also applied. The study group consisted of an initial analysis cohort (n = 191) and a second validation cohort from a separate institution (n = 97). In the initial analysis cohort, our histologic grading system provided prognostic stratification for GVHD-related death within 6 months (p = 0.0004, AUC = 0.705). The Lerner system performed similarly in terms of providing prognostic stratification for GVHD-related death (p = 0.0001, AUC = 0.707). In the external validation cohort, our histologic grading system was not associated with GVHD-related death (p = 0.14, AUC = 0.621), but the Lerner system was associated with GVHD-related death (p = 0.048, AUC = 0.663). While our grading system may have some advantages compared to the Lerner system, due to lack of reproducibility we do not currently recommend widespread adoption of this system. Nonetheless, we present a standardized tool for assessing both apoptosis and crypt damage. Future studies assessing alternative histologic grading systems with external validation and further examination the lower apoptotic threshold for GVHD diagnosis are warranted.

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.

How many serial sections are needed to detect apoptosis in endoscopic biopsies with gastrointestinal graft versus host disease?

Aims

The hallmark histological feature of acute gastrointestinal graft versus host disease (GI GVHD) is epithelial apoptosis. This is the first formal evaluation of how many serial sections are required to consistently detect apoptotic bodies in endoscopic biopsies from various GI locations in patients with clinically validated GI GVHD.

Methods, results and conclusions

Assessment of 1008 serial sections showed that apoptotic bodies are uniformly distributed among such sections of gastric, duodenal and colorectal biopsies from these patients. Assessment of 59 further biopsies showed that assessing 12 serial sections should suffice to detect GVHD in gastric, duodenal and colorectal biopsies using thresholds of one apoptotic body per biopsy fragment or one apoptotic body per 4 mm2. Assessing 12 serial sections should also suffice to detect GVHD in duodenal and colorectal biopsies using the threshold of 6 apoptotic bodies per 10 contiguous crypts, but it remains uncertain whether this assessment and threshold can be applied to gastric biopsies.