Centralized intestinal organoid generation is a feasible and safe approach for personalized medicine as demonstrated in the HIT-CF Europe Organoid Study.

BACKGROUND: Patient-derived intestinal organoids (PDIOs) show great potential as in vitro drug testing platform for personalised medicine in Cystic Fibrosis and oncology. PDIOs can be generated by culturing adult stem cells obtained through rectal forceps biopsy or suction biopsy, but the safety of these procedures and the success rates of generating organoids after shipment to a centralized lab using these procedures has not been studied in this context. We here report the safety and success rates of both biopsy procedures and the subsequent generation of PDIOs in the international multicentre HIT-CF Organoid Study. METHODS: 502 biopsy procedures were conducted, on 489 adult people with Cystic Fibrosis from 33 different hospitals across 12 countries. Depending on the preference of the hospital, either rectal forceps biopsies or suction biopsies were obtained and internationally shipped to a central laboratory for organoid generation. RESULTS: No adverse events were reported for 280 forceps biopsy procedures, while 222 rectal suction biopsy procedures resulted in 2 adverse events, namely continued bleeding and a probably nonrelated gastroenteritis. The success rate of organoid generation from all biopsies was 95%, and the main reason for failure was insufficient sample viability (3.2%). CONCLUSION: Our results indicate that both rectal suction biopsy and forceps biopsy procedures are safe procedures. The high success rates of PDIO generation from the obtained tissue samples demonstrate the feasibility of the organoid technology for personalised in vitro testing in an international setting.

A current view of mitochondria damage and the diversity of lipopigment inclusions in neuronal ceroid lipofuscinose type 2 from rectal biopsy.

Neuronal ceroid lipofuscinoses (NCLs) are a growing group of neurodegenerative storage diseases, in which specific features are sought to facilitate the creation of a universal diagnostic algorithm in the future. In our ultrastructural studies, the group of NCLs was represented by the CLN2 disease caused by a defect in the TPP1 gene encoding the enzyme tripeptidyl-peptidase 1. A 3.5-year-old girl was affected by this disease. Due to diagnostic difficulties, the spectrum of clinical, enzymatic, and genetic tests was extended to include analysis of the ultrastructure of cells from a rectal biopsy. The aim of our research was to search for pathognomonic features of CLN2 and to analyse the mitochondrial damage accompanying the disease. In the examined cells of the rectal mucosa, as expected, filamentous deposits of the curvilinear profile (CVP) type were found, which dominated quantitatively. Mixed deposits of the CVP/fingerprint profile (FPP) type were observed less frequently in the examined cells. A form of inclusions of unknown origin, not described so far in CLN2 disease, were wads of osmophilic material (WOMs). They occurred alone or co-formed mixed deposits. In addition, atypically damaged mitochondria were observed in muscularis mucosae. Their deformed cristae had contact with inclusions that looked like CVPs. Considering the confirmed role of the c subunit of the mitochondrial ATP synthase in the formation of filamentous lipopigment deposits in the group of NCLs, we suggest the possible significance of other mitochondrial proteins, such as mitochondrial contact site and cristae organizing system (MICOS), in the formation of these deposits. The presence of WOMs in the context of searching for ultrastructural pathognomonic features in CLN2 disease also requires further research.

Clinical relevance of inflammation on rectal biopsy for Hirschsprung disease: An outcomes analysis.

OBJECTIVES: Inflammation on diagnostic rectal biopsy for children with suspected Hirschsprung disease (HSCR) is reported on pathology, and its significance is unknown. We describe the management and outcomes of a cohort with inflammation on rectal biopsy compared to those without. Specifically, to address the hypothesis that inflammation on diagnostic biopsy is associated with increased complication rates irrespective of intervention type and timing. METHODS: A single institution retrospective review of children with HSCR who underwent biopsy and endorectal pull-through (ERPT) from 2010 to 2020 was performed. The primary outcome was overall complications at 30-days following ERPT. Secondary outcomes included timing and type of operative intervention as well as postoperative enterocolitis diagnosed within 6-months of ERPT. RESULTS: Forty-nine children were identified; inflammation was present on diagnostic biopsy for 17 children. Those with inflammation were more likely to have clinical evidence of enterocolitis at the time of biopsy (p = 0.001) and were more likely to undergo leveling colostomy before ERPT (p = 0.01). Children with inflammation had a higher anastomotic leak rate (p = 0.04). Subgroup analysis of patients with inflammation undergoing primary ERPT versus leveling colostomy demonstrated no significant difference in outcomes following definitive ERPT. CONCLUSIONS: Our study suggests inflammation on diagnostic rectal biopsy for HSCR is associated with increased anastomotic leak rates. While additional prospective studies are indicated, attention to methods of mitigating inflammation and confirming its resolution before definitive pull-through may be of benefit for improving clinical outcomes in patients found with inflammation on diagnostic rectal biopsy.

Diagnostic accuracy of barium enema versus full-thickness rectal biopsy in children with clinically suspected Hirschsprung's disease: A comparative cross-sectional study.

Background and Aims: Hirschsprung's disease (HSD) remains a common cause of pediatric intestinal obstruction. Barium contrast enema (BE) is the primary imaging modality for the evaluation of clinically suspected cases. Here, we aimed to assess the diagnostic accuracy of BE in children with clinically suspected HSD when compared to a gold standard full-thickness rectal biopsy (FTRB). Methods: We recruited and consecutively enrolled children with clinically suspected HSD at two tertiary teaching hospitals. Participants underwent BE imaging and two radiologists interpreted the findings independently. Participants further underwent FTRB by pediatric surgeons as the confirmatory test. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and receiver operating characteristics (ROC) with the area under the curve (AUC) were calculated on Stata version 14.2, taking FTRB as the standard. Results: We enrolled 55 cases, of which 49 completed the evaluation and were included in the final analysis. The median age was 9.4 months (interquartile range: 2-24], with a male-to-female ratio of 4.4:1. The sensitivity, specificity, PPV, and NPV of BE were 0.95 (95% confidence interval [CI] [0.81-0.99]), 0.73 (95% CI [0.39-0.94]), 0.92 (95% CI [0.82-0.97]), and 0.80 (95% CI [0.50-0.94]), respectively. On AUC, the diagnostic accuracy of BE compared to the confirmatory FTRB was 0.84 (95% CI [0.69-0.98]). The diagnostic accuracy was higher in neonates (ROC: 1.00) when compared to infants (ROC: 0.83) or those above 1 year of age (ROC: 0.798). HSD-suggestive BE findings were associated with absence of ganglion cells on FTRB (χ 2 = 23.301, p < 0.001). Inverted rectosigmoid ratio and transition zone were more sensitive in detecting HSD of 0.92 (95% CI [0.74-0.98]) and 0.81 (95% CI [0.63-0.92]), respectively. Conclusion: BE is sufficiently accurate in the diagnosis of children with HSD, suggesting BE would likely be used to inform surgical management in settings where confirmatory biopsy is lacking. However, clinical judgment is warranted in interpreting negative BE findings.

Early Detection and Intervention for Hirschsprung's Disease: A Key to Successful Outcomes.

Hirschsprung's disease is a congenital disorder characterized by the absence of nerve cells in the colon muscles, leading to difficulties in evacuating stool. This case report describes a newborn patient presenting with typical symptoms of the disease, including abdominal distension, constipation, diarrhea, and fever. The patient's initial laboratory investigations revealed anemia (Hb: 9.80 g/dL), low RBC count (3.50 million/cu mm), elevated RDW (16.70%), increased WBC count (11 000/cu mm), and raised platelet levels (891 000/µL) along with an elevated CRP (3.22). The baby received a comprehensive treatment regimen, including blood transfusion, Syp. MVBC, Enterogermina, Inj. Pan, Inj. Metro, Inj. Piptaz, Inj. Vancomycin, Calcium gluconate, and Inj. Aminoven. Following this treatment and necessary surgical intervention, the patient demonstrated significant improvement in frequent bowel movements and alleviation of other symptoms. This case highlights the importance of prompt diagnosis and multidisciplinary management for favorable outcomes in infants with Hirschsprung's disease.

Full-Thickness Rectal Biopsy in Children Suspected of Having Hirschsprung's Disease: The Inconclusive Biopsy.

The diagnosis of Hirschsprung's disease relies on histologically proven aganglionosis and nerve trunk hypertrophy in rectal biopsies. Although the frequency of inconclusive biopsies is relatively low, it is a relevant clinical problem. The aim of the present study was to investigate whether a re-evaluation of archived full-thickness biopsies (FTBs) stained with hematoxylin and eosin (HE), together with immune histochemical (IHC) staining, would be diagnostic in biopsies otherwise deemed inconclusive at initial examination with HE only. A total of 34 inconclusive biopsies in 31 patients were identified. From each tissue block, three slices were cut and stained with HE, S100 and calretinin. A blinded pathologist examined the tissue samples. At re-evaluation, one patient was found positive for HD and 11 negative for HD with both HE and IHC staining, respectively. In all 12 cases, the result was confirmed by the final diagnosis at a 5-year follow-up. The rest of the cases were deemed inconclusive. A re-evaluation of the remaining tissue from the biobank might have saved one third of the children from a re-biopsy. The value of adding IHC to conventional HE staining is dubious.

Rectal Biopsy for Hirschsprung's Disease: A Multicentre Study Involving Biopsy Technique, Pathology and Complications.

BACKGROUND: The heterogeneity of rectal biopsy techniques has encouraged us to search for a surgical and pathological standardisation of this diagnostic technique to exclude Hirschsprung's disease. The different amounts of information on the anatomopathology report prompted us to compile a template for the anatomopathology report for diagnostic rectal biopsies for surgical colleagues and pathologists working on Hirschsprung's disease. METHODS: We gathered the anonymous biopsy information and its pathology information from five hospitals for all patients in which rectal biopsies were taken to diagnose Hirschsprung's disease over two years (2020-2021). RESULTS: Of the 82 biopsies, 20 suction (24.4%), 31 punch (37.8%) and 31 open biopsies (37.8%) were taken. Of all biopsies, 69 were conclusive (84.2%), 13 were not (15.8%). In the suction biopsy group, 60% were conclusive and 40% were not; for punch biopsy, the values were 87% and 13%, respectively and for open biopsy, 97% and 3%. Inconclusive results were due to insufficient submucosa in 6/8 suction biopsies, 4/4 punch biopsies and 0/1 open biopsies. An insufficient amount of submucosa was the reason for an inconclusive result in 6/20 cases (30%) after suction biopsy, 4/31 (12.9%) cases after punch biopsy and 0 cases (0%) after open biopsy. We had one case with major postoperative bleeding post suction biopsy; there were no further adverse effects after biopsy. CONCLUSIONS: Diagnostic rectal biopsies in children are safe. Non-surgical biopsies are more likely to give inconclusive results due to smaller amounts of submucosa present in the specimen. Open biopsies are especially useful when previous non-surgical biopsies are inconclusive. An experienced pathologist is a key factor for the result. The anatomopathology report should specify the different layers present in the specimen, the presence of ganglion cells and hypertrophic nerve fibres, their description and a conclusion.

A new systematization of histological analysis for the diagnosis of Hirschsprung's disease.

BACKGROUND: Hirschsprung's Disease (HD) is characterized by intestinal sub-occlusion and the absence of enteric ganglion cells. A rectal biopsy examination is performed to confirm the diagnosis. In a recent study, we demonstrated that the analysis of 60 sections of rectal mucosa and submucosa stained by H&E may ensure a 90% diagnostic accuracy. Although the need to analyze so many sections makes the process of reading the slides more time-consuming, this encouraged us to study their distribution in the healthy rectal submucosa, to simplify the diagnosis. OBJECTIVES: To develop a method that facilitates HD diagnosis by studying the distribution of ganglion cells in the submucosal plexus. METHODS: Using the calretinin technique, we studied the distribution of plexuses in 60 fragments of rectal submucosa from 19 cadavers. After the study, the reading method created was used for diagnosis in 47 cases of suspected HD, using H&E staining. The accuracy was verified by comparing the results obtained with H&E to those obtained with the acetylcholinesterase technique, the golden standard in our laboratory. RESULTS: The study of submucosal plexus distribution showed that just by examining the submucosal region every 20 µm, approximately, it is possible to locate a ganglionic plexus, and we have already been able to diagnose HD with 93% accuracy. CONCLUSION: The study of ganglion cell distribution enabled the creation of a simplified method for reading the slides. The method applied achieved good accuracy and it can be used as an alternative method in HD diagnosis.

A Case Report of Hirschsprung's Disease in a Neonate: Early Detection and Review of Management.

Hirschsprung's disease is a rare disease characterized by the complete absence of ganglionic cells in the colon, thereby causing loss of peristalsis movement of the bowel. Most cases are diagnosed before the age of one. Here, we present a case of a newborn baby boy who was not feeding well and then developed a distended abdomen and began bilious vomiting. Blood mucoid stools were also observed. The diagnosis of Hirschsprung's disease was confirmed through a full-thickness rectal biopsy, and the Duhamel surgical procedure was performed as a course of treatment all within the first few days of birth. No complications were reported, and the baby was safely discharged after seven days. This case demonstrates the importance of timely treatment after prompt diagnosis due to the early recognition of the severe symptoms. Even though this disease is rare, pediatricians should be trained to recognize and treat the child to prevent further detrimental outcomes.

Hirschsprung Disease for the Practicing Surgical Pathologist.

OBJECTIVES: Hirschsprung disease (HD) is a congenital condition defined by the absence of ganglion cells in the distal-most portion of the gastrointestinal tract. Biopsies and resections for HD can be adrenaline inducing for the general surgical pathologist because specimens are infrequent; HD is 1 of only a few neuroanatomic diseases that general surgical pathologists diagnose; numerous preanalytic factors (eg, biopsy adequacy, surgeon sampling protocol, processing artifacts) can affect histologic interpretation; and most importantly, the diagnosis has high stakes. METHODS: We provide a comprehensive overview of the background, relevant clinical procedures, and pathologic assessment of HD. Grossing and frozen section protocols, an algorithmic approach to diagnosis, and histologic pearls and pitfalls are also discussed. RESULTS: Evaluation and recognition of the features of HD have evolved significantly in the past 2 decades with the discovery of the value of calretinin immunohistochemistry in the late 2000s and the recent development of straightforward and reproducible histologic criteria for identification of the HD transition zone. CONCLUSIONS: These advancements have substantially improved the pathologist's ability to reliably evaluate for HD. Nonetheless, as with any high-stakes surgical pathology specimen, clear communication with the clinical team is essential.

A new systematization of histological analysis for the diagnosis of Hirschsprung's disease

Abstract Background: Hirschsprung's Disease (HD) is characterized by intestinal sub-occlusion and the absence of enteric ganglion cells. A rectal biopsy examination is performed to confirm the diagnosis. In a recent study, we demonstrated that the analysis of 60 sections of rectal mucosa and submucosa stained by H&E may ensure a 90% diagnostic accuracy. Although the need to analyze so many sections makes the process of reading the slides more time-consuming, this encouraged us to study their distribution in the healthy rectal submucosa, to simplify the diagnosis. Objectives: To develop a method that facilitates HD diagnosis by studying the distribution of ganglion cells in the submucosal plexus. Methods: Using the calretinin technique, we studied the distribution of plexuses in 60 fragments of rectal submucosa from 19 cadavers. After the study, the reading method created was used for diagnosis in 47 cases of suspected HD, using H&E staining. The accuracy was verified by comparing the results obtained with H&E to those obtained with the acetylcholinesterase technique, the golden standard in our laboratory. Results: The study of submucosal plexus distribution showed that just by examining the submucosal region every 20 µm, approximately, it is possible to locate a ganglionic plexus, and we have already been able to diagnose HD with 93% accuracy. Conclusion: The study of ganglion cell distribution enabled the creation of a simplified method for reading the slides. The method applied achieved good accuracy and it can be used as an alternative method in HD diagnosis.

Calretinin Staining in Anorectal Line Biopsies Accurately Distinguished Hirschsprung Disease in a Retrospective Study.

INTRODUCTION: The absence of submucosal ganglion cells does not reliably distinguish Hirschsprung disease from non Hirschsprung disease in anorectal line biopsies. Calretinin staining might be helpful in these biopsies. To determine its value, we analyzed calretinin positive mucosal neurites in anorectal line biopsies. METHODS: Two pediatric pathologists, without access to patient data, evaluated calretinin positive mucosal neurites in anorectal line junctional mucosa in archival rectal biopsies contributed by 17 institutions. A separate investigator compiled patient information and sent data for statistical analysis. RESULTS: Biopsies with anorectal junctional mucosa from 115 patients were evaluated for calretinin positive mucosal neurites. 20/20 Hirschsprung disease biopsies were negative. 87/88 non Hirschsprung disease biopsies and 7/7 post pullthrough Hirschsprung disease neorectal biopsies were positive. Statistical analysis of the 108 non pullthrough biopsies yielded an accuracy of 99.1% (sensitivity 100%, specificity 98.9%). Age range was preterm to 16 years. Biopsy size was less than 1 mm to over 1 cm. CONCLUSIONS: Absence of calretinin positive mucosal neurites at the anorectal line was highly accurate in distinguishing Hirschsprung disease from non Hirschsprung disease cases in this blinded retrospective study. Calretinin staining is useful for interpreting biopsies from the physiologic hypoganglionic zone up to the anorectal line.

The utility of the 24-h delayed film of barium enema for detecting the dysganglionic bowel segment in Hirschsprung's disease.

Background: Preoperative evaluation of the dysganglionic bowel segment is critical for establishing the optimal resection strategy for Hirschsprung's disease (HSCR), which facilitates patient outcomes. Objective: We set out to determine the utility of the 24-h delayed film of barium retention in predicting the length of dysganglionic bowel segment in HSCR. Materials and methods: A retrospective study of patients with clinically suspicious HSCR who underwent a preoperative 24-h delayed film of barium enema and were surgically treated from January 2015 to December 2019 was conducted. Results: Two hundred and 58 patients were enrolled in this study. The sensitivity, specificity, positive and negative predictive values (NPVs) of the 24-h delayed film of barium enema to predict the neuropathological segment were 89.1, 91.5, 91.3, and 89.4%, respectively. The Youden index was 80.6%, with a kappa value of 0.806 (P < 0.001). The correlation rate between barium retention level and pathological results was 72.7% (16/22) when aganglionosis was restricted within the mid-distal rectum (short-segment type), increasing to 92.0% (46/50) and 93.5% (174/186) for patients that had aganglionosis extended beyond the mid-distal rectum (classical type) and sigmoid colon (long-segment type), respectively. Lastly, patients younger than 3 months showed a lower correlation rate (72.2%) compared to patients aged 3-12 months (91.0%) and > 12 months (92.6%). Conclusions: Our investigation of the 24-h delayed film of barium enema performed for patients suspected of having HSCR indicated that the barium retention level remains crucial in predicting dysganglionic bowel segment, which contributes to the decision-making for surgical physicians.

Rectal suction biopsy versus incisional rectal biopsy in the diagnosis of Hirschsprung disease.

BACKGROUND: Hirschsprung disease is one of the most common congenital anomalies that affect colorectal function. Rectal biopsy demonstrating the absence of ganglion cells in the affected bowel is the gold standard for diagnosis. Suction and incisional rectal biopsies are appropriate methods for obtaining diagnostic tissue. The goal of this study is to determine if any differences in adequacy exist between suction and incisional rectal biopsies at our institution. METHODS: We conducted a retrospective review of suction and incisional rectal biopsies for inadequacy per procedure at a tertiary pediatric hospital. Each procedure for rectal biopsy was also evaluated by a number of biopsies per procedure. We used a two-sample test of proportions to compare the inadequacy of suction vs. incisional biopsies. RESULTS: 133 rectal suction biopsy procedures (227 biopsies) and 125 incisional biopsy procedures (140 biopsies) were analyzed. In patients 6 months of age and older, the percentage of inadequate procedures was substantially higher in the suction biopsy group (24.1% vs 0.9%, p < 0.01). CONCLUSIONS: A substantially higher proportion of inadequacy was found in the suction rectal biopsy group compared to the incisional cohort among the older patient cohort, suggesting incisional biopsies should be strongly considered as the primary rectal biopsy method in patients older than 6 months.

Diagnostic accuracy of haematoxylin-eosin staining in comparison to calretinin and S100 for the assessment of ganglion cells in rectal biopsy.

OBJECTIVE: To assess the diagnostic accuracy of haematoxylin-eosin staining in clinically suspected Hirschsprung disease, and to compare the findings with calretinin and S100 immunohistochemistry. METHODS: The retrospective study was conducted at the AL-Khansaa Teaching Hospital, Nineveh, Iraq, and comprised data from January 2017 to October 2020 of rectal suction biopsies of patients with clinically and radiologically suspected Hirschsprung disease. Histopathology and immunohistochemistry were performed. Data was analysed using SPSS 16. RESULTS: Of the 114 patients, 74(64.9%) were males and 40(35.1%) were females. Based on histology, 28(24.6%) cases were negative for ganglion cells, and, of them 25(89.2%) revealed nerve bundle hypertrophy. The diagnostic accuracy for the detection of ganglion cell and nerve hypertrophy using haematoxylin-eosin stain was 99.1% and 94.4%, respectively. Correlation of haematoxylin-eosin staining with calretinin and S100 was statistically near perfection (κ= 0.976 and κ = 0.923), respectively. CONCLUSIONS: The mainstay to confirm or exclude Hirschsprung disease remains an accurate histopathological evaluation of the haematoxylin-eosin-stained sections of an adequate colorectal biopsy.

Evaluation of diagnostic factors used to refer children with constipation for rectal biopsies.

PURPOSE: Children with constipation and suspected Hirschsprung's disease are referred for rectal biopsy. Since this is an invasive procedure, appropriate indications should be applied to minimize the number of "unnecessary" biopsies. METHODS: We reviewed all constipated children who underwent a rectal biopsy to diagnose a possible Hirschsprung's disease at a tertiary referral hospital over a 6-year period (2013-2018). We registered clinical and demographic factors in these children and conducted correlation and multivariate regression analysis to evaluate the relation between these factors and a diagnosis of Hirschsprung's disease. RESULTS: We identified 225 children, aged 0-17 years. In total, Hirschsprung's disease was diagnosed in only 49/225 (22%). Among the 49 children with Hirschsprung's disease, 29 (59%) were diagnosed in the neonatal period. Among girls, HD was confirmed in only 10/101 (10%) children, and only 1 of these 10 girls was older than 6 months at the time of the biopsy. The following factors correlated significantly with Hirschsprung's disease diagnosis in children older than 1 month: "male sex", "failure to thrive", "gross abdominal distention plus vomiting" and "fulfils the Rome 4 criteria for functional constipation". CONCLUSION: In children referred for rectal biopsy, the factors most indicative of Hirschsprung's disease were "male sex", "failure to thrive", "gross abdominal distention plus vomiting" and "fulfils the Rome 4 criteria for functional constipation". Notably, the prevalence of Hirschsprung's disease decreased with the increasing age of the children. Girls referred for a biopsy rarely had Hirschsprung's disease, especially those older than 1 month.

Systematic biopsy should not be omitted in the era of combined magnetic resonance imaging/ultrasound fusion-guided biopsies of the prostate.

PURPOSE: To evaluate prostate cancer detection rates with classical trans-rectal ultrasound-guided systematic 10-core biopsies (SB), targeted biopsies (TB) guided by magnetic resonance (MR)/US fusion imaging and their combination in biopsy-naïve and patients with previously negative prostate biopsies. We compared pathology results after radical prostatectomy with biopsy findings. METHODS: Consecutive patients with prostate imaging-reporting and data system lesions grade ≥ 3 submitted to MRI/US-guided TB and subsequent standard 10-core SB between December 2015 and June 2019 were analyzed. RESULTS: Detection rate (TB- or SB-positive) in 563 included patients (192 naïve, 371 with previous biopsies) was 56.7% (67.7% for the first, 50.9% for repeated biopsies). With TB (disregarding SB), the rates were 41.4%, 52.1% and 35.8%, respectively. With SB (disregarding TB), the rates were 49.1%, 63.0% and 41.8%, respectively. Eventually, 118 patients underwent surgery and clinically significant cancer was found in 111 (94.1%) specimens. Of those, 23 (20.7%) would have been missed had we relied upon a negative TB and 14 (12.6%) would have been missed had we relied upon a negative SB, disregarding a positive finding on the alternative biopsy template. CONCLUSION: SB should not be omitted since TB and SB combination have higher detection rate of clinically relevant prostate cancer than either procedure alone.

Safety and Accuracy of Suction Rectal Biopsy in Preterm Infants.

Purpose: Most pediatric surgeons give little attention to the diagnosis of Hirschsprung disease (HD) in preterm infants. We aimed to explore the safety and accuracy of suction rectal biopsy (SRB) for diagnosing HD in preterm infants. Methods: A retrospective review was conducted of 45 preterm patients who underwent SRB from 2015 to 2019 in our hospital. We collected the clinical characteristics and pathology results of the patients and information on follow-up. The sensitivity and specificity of SRB for HD diagnosis were calculated. Results: The median gestational age of the patients was 35 weeks (range: 28.9-36.9 weeks), the median gestational age at biopsy was 38.6 weeks (range: 33.4-60.0 weeks), and the median weight was 2,790 g (range: 1,580-4,100 g). Fifteen patients (33.3%) were positive for HD, which was confirmed after pull-through surgery. Ganglion cells were present in 30 patients. The diagnosis of HD was excluded in 29 patients after discharge follow-up. The sensitivity of SRB ranged from 93.7 to 100%, and the specificity was 100%. No complications occurred after SRB among the patients whose biopsy age was <37 weeks (10 patients) or biopsy weight was <2,000 g (five patients). Conclusion: SRB is accurate and safe for diagnosing HD in late preterm infants.

Usefulness of digestive biopsy in the diagnosis of graft-versus-host disease. / Utilidad de la biopsia digestiva para el diagnóstico de la enfermedad injerto contra huésped.

INTRODUCTION: Graft-versus-host disease (GVHD) is a frequent complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT), with high morbidity and mortality rates. Intestinal clinical signs are unspecific, which means differential diagnosis with infections and drug-related etiology should be carried out. Even though intestinal biopsy is widely considered as the gold standard technique, there is no consensus as to which sampling method is best. OBJECTIVE: To assess the results of the biopsy techniques used in patients with suspected intestinal GVHD. MATERIAL AND METHODS: A retrospective study of patients with suspected intestinal GVHD undergoing allo-HSCT from 2010 to 2019 was carried out. They were assessed through digestive biopsy - esophagogastroduodenal biopsy (upper GI endoscopy - UGIE) or rectal biopsy (colonoscopy or direct biopsy). Quantitative variables, expressed as median and interquartile range, and qualitative variables, expressed as absolute frequency and percentage, were collected. RESULTS: 23 patients were studied, 60.9% of whom were male. Median age at biopsy was 9 years (7-14 years). UGIE was used in 47.8% of patients (n=11), colonoscopy was used in 26.1% of patients (n=6), and direct biopsy was used in 34.8% of patients (n=8), with GVHD positive results in 2 (18.2%), 2 (33.3%), and 4 (50%) patients, respectively. CONCLUSIONS: Samples taken through direct biopsy stand as an effective alternative in GVHD diagnosis.

INTRODUCCION: La enfermedad injerto contra huésped (EICH) es una complicación frecuente de los trasplantes de células precursoras hematopoyéticas alogénicos (alo-TCPH), con gran morbimortalidad. La clínica intestinal es inespecífica, planteando el diagnóstico diferencial con infecciones y etiología medicamentosa. Aunque las biopsias intestinales son el gold standard, no existe consenso sobre la mejor técnica para obtenerlas. OBJETIVO: Evaluar los resultados de las técnicas empleadas para obtener biopsias en pacientes con sospecha de EICH intestinal. MATERIAL Y METODOS: Estudio retrospectivo que incluye pacientes sometidos a alo-TCPH entre 2010 y 2019, con sospecha de EICH intestinal estudiados mediante biopsias digestivas: esofagogastroduodenales (endoscopia digestiva alta - EDA) o rectales (colonoscopia o biopsia directa). Recogimos variables cuantitativas, expresadas como mediana y rango intercuartílico; y cualitativas, expresadas en frecuencia absoluta y porcentaje. RESULTADOS: Estudiamos 23 pacientes (60,9% varones). La mediana de edad en el momento de la biopsia fue 9 años (7-14 años). Empleamos EDA en el 47,8% (n= 11), colonoscopia en 26,1% (n= 6) y biopsia directa en el 34,8% (n= 8); siendo positivas para EICH en 2 (18,2%), 2 (33,3%) y 4 (50%), respectivamente. CONCLUSIONES: Las muestras obtenidas mediante biopsia directa se plantean como una alternativa eficiente en el diagnóstico del EICH.

Autopsy Study of Calretinin Immunohistochemistry in the Anorectal Canal in Young Infants and Potential Implications for Rectal Biopsy Approach in the Neonatal Period.

BACKGROUND: Absent submucosal ganglion cells in biopsies 1-3 cm above the pectinate line establishes the pathologic diagnosis of Hirschsprung Disease (HD). Calretinin stains both ganglion cells and their mucosal neurites and has gained importance in HD diagnosis. Absent calretinin positive mucosal neurites in biopsies at the appropriate level above the pectinate line is highly specific for HD. Whether this applies to lower biopsies is uncertain. To address this, we studied anorectal canal autopsy specimens from infants. METHODS: We performed an autopsy study of infant anorectal canal specimens to describe calretinin staining in this region. Calretinin staining was correlated with histologic and gross landmarks. RESULTS: In all 15 non-HD specimens, calretinin positive mucosal neurites were present in glandular mucosa up to the anorectal line where neurites rapidly diminished. Age range was preterm 26 weeks to 3 months. CONCLUSIONS: Calretinin positive mucosal neurites are present in glandular mucosa up to the anorectal line in young infants. This is potentially important regarding neonatal HD biopsy level and diagnosis. Positive calretinin staining at the anorectal line favors normal innervation making HD unlikely. Absent calretinin positive neurites in glandular mucosa is worrisome for HD in young infants, regardless of location.