Granulomatous enterocolitis associated with Hermansky-Pudlak syndrome

Recurrent perianal abscess in a patient with Hermansky-Pudlak syndrome-associated granulomatous colitis: a case report

Hermansky-Pudlak syndrome (HPS) is a rare genetic disease consisting of the triad of oculocutaneous albinism, bleeding diathesis, and pigmented reticuloendothelial cells. In HPS patients' granulomatous colitis could be an additional feature and perianal abscess could be seen in such patients. We report a patient with HPS-associated granulomatous colitis, refractory to medical treatment, and perianal involvement. Patients with HPS-associated granulomatous colitis and perianal involvement may require multiple surgical interventions and there is no consensus yet for treatment in such patients.

A Pattern-based Pathology Approach to Very Early-onset Inflammatory Bowel Disease: Thinking Beyond Crohn Disease and Ulcerative Colitis

Very early-onset inflammatory bowel disease (VEO-IBD), IBD diagnosed in children younger than 6 years old, is phenotypically and genetically distinct from older onset IBD. Monogenic and digenic causative defects, particularly in primary immunodeficiency and intestinal epithelial barrier genes, have been identified in a subset of patients with VEO-IBD allowing for targeted therapies and improved outcomes. However, these findings are the minority, thus strategies to correctly diagnose patients, including identification of specific histopathologic findings with correlating clinical and laboratory features may provide critical and necessary insight into mechanisms of disease pathogenesis and subsequent therapeutic options. In this article, we review the pathologic findings seen in patients with VEO-IBD and outline a pattern-based approach to diagnosis using examples from primary immunodeficiencies with gastrointestinal manifestations.

Inflammatory bowel disease in Hermansky-Pudlak syndrome: a retrospective single-centre cohort study

BACKGROUND

Knowledge about inflammatory bowel disease (IBD) in patients with Hermansky-Pudlak syndrome (HPS), a rare autosomal recessive disorder characterized by defective biogenesis of lysosome-related organelles, could provide insights into IBD in general.

OBJECTIVE

To expand the understanding of IBD in patients with HPS.

METHODS

Retrospective review of records from patients with HPS evaluated at the National Institutes of Health Clinical Center from 1995 to 2019 was conducted. Clinical features of IBD, genotyping results and histologic findings of colectomy specimens were analysed.

RESULTS

IBD affected 37 (14.2%; 12 male, 25 female) of 261 patients with HPS. Median age of onset was 17 years; range was 1 to 52 years. The most common symptoms of HPS IBD were hematochezia, abdominal pain and loose stools. Fistulae or extra-intestinal manifestations developed in 30% or 22%, respectively. Genotyping showed that patients with biallelic variants in HPS1, HPS3, HPS4 or HPS6 were diagnosed with IBD. Six children had very early-onset IBD. Patients with HPS-3 had mild manifestations of IBD. Medical therapy and bowel resection were utilized to treat 73% and 35% of patients with HPS IBD, respectively; 7 of 13 patients receiving anti-tumor necrosis factor alpha therapy had prolonged clinical responses. Active cryptitis, chronic inflammatory changes, granulomas and ceroid lipofuscinosis were histopathologic findings in three colectomy specimens.

CONCLUSIONS

IBD resembling Crohn's disease affects some patients with HPS; genetic heterogeneity is a feature of HPS IBD. HPS3 is a new gene associated with human IBD. Very early-onset IBD can develop in HPS.

Hermansky-Pudlak Syndrome and Lung Disease: Pathogenesis and Therapeutics

Hermansky-Pudlak Syndrome (HPS) is a rare, genetic, multisystem disorder characterized by oculocutaneous albinism (OCA), bleeding diathesis, immunodeficiency, granulomatous colitis, and pulmonary fibrosis. HPS pulmonary fibrosis (HPS-PF) occurs in 100% of patients with subtype HPS-1 and has a similar presentation to idiopathic pulmonary fibrosis. Upon onset, individuals with HPS-PF have approximately 3 years before experiencing signs of respiratory failure and eventual death. This review aims to summarize current research on HPS along with its associated pulmonary fibrosis and its implications for the development of novel treatments. We will discuss the genetic basis of the disease, its epidemiology, and current therapeutic and clinical management strategies. We continue to review the cellular processes leading to the development of HPS-PF in alveolar epithelial cells, lymphocytes, mast cells, and fibrocytes, along with the molecular mechanisms that contribute to its pathogenesis and may be targeted in the treatment of HPS-PF. Finally, we will discuss emerging new cellular and molecular approaches for studying HPS, including lentiviral-mediated gene transfer, induced pluripotent stem cells (iPSCs), organoid and 3D-modelling, and CRISPR/Cas9-based gene editing approaches.

Treatment of Hermansky-Pudlak syndrome Associated granulomatous colitis with anti-TNF agents: case series and review of literature

Hermansky-Pudlak syndrome is a rare syndrome characterized by bleeding diathesis due to platelet dysfunction, oculocutaneous albinism and other systemic involvements. Granulomatous colitis may occur in the disease course and have similarities with Crohn's disease. Herein, we present four cases with Hermansky-Pudlak syndrome associated colitis with the longest follow-up period having various responses to different anti-TNF agents. Four patients with Hermansky-Pudlak syndrome colitis were started on anti-TNF agents between 2008 and 2013. After a mean follow-up period of 7.5 years, two of four patients exhibited a significant improvement in symptoms, whereas the other two experienced undesirable disease course. Although having many similarities with Crohn's disease; Hermansky-Pudlak syndrome colitis appears to have lower anti-TNF response rates. Pathophysiological differences need to be enlightened to find more appropriate therapeutic targets for Hermansky-Pudlak syndrome colitis.

Surgical treatment of monogenic inflammatory bowel disease: A single clinical center experience

PURPOSE

With the wide application of immunologic reconstitution treatment, such as hematopoietic stem-cell transplantation (HSCT), most patients of inflammatory bowel disease (IBD) with immunodeficiency owing to monogenic abnormalities need surgical intervention during the course of treatment, which is quite different from traditional IBD surgery. The aim of this study was to generalize the surgical strategies as a part of comprehensive therapy for these rare diseases.

METHODS

A retrospective study was conducted based on the clinical data of children with immunodeficiency-derived IBD who underwent surgical treatment in Children's Hospital of Fudan University between January 2015 and December 2017.

RESULTS

A total of 18 patients with monogenic abnormalities were enrolled. The major surgical indications included 11 cases of acute or chronic intestinal obstructions, 4 refractory intestinal infections, and 3 pneumoperitoneum, while 12 cases had perforations noted during intraoperative exploration. All of the patients underwent varieties of enterostomies to divert the affected or obstructed intestine during the primary surgery. Wound infections or dehiscence occurred in 7 patients, and 2 patients underwent reoperations for adhesive intestinal obstruction and prolapse. Postoperatively, 15 patients survived, 13 of which achieved immune reconstitution through subsequent HSCT or immunoglobulin supplementation. In the second-stage surgery, a posterior sagittal approach rectal resection was performed in 5 patients with complex anorectal complications. Twelve patients had undergone stoma closure procedures.

CONCLUSION

Surgical intervention should be performed earlier because the perforations are usually insidious in monogenic IBD. Preventative enterostomies are suggested in preparation for HSCT among patients with severe anorectal complications. Wound infections are the most common complication after the primary operation. Posterior sagittal rectal resection is a good option for patients with complex anorectal complications.

TYPE OF STUDY

Clinical research paper.

LEVEL OF EVIDENCE

Level IV.

Crohn’s-like acute severe colitis associated with Hermansky-Pudlak syndrome: A case report

BACKGROUND

Hermansky-Pudlak syndrome (HPS) is a rare autosomal recessive disorder characterized by oculocutaneous albinism, platelet storage pool deficiency and systemic complications associated with ceroid deposition in the reticuloendothelial system. HPS types 1 and 4 are associated with Crohn’s disease (CD)-like gastrointestinal disorders, such as granulomatous enterocolitis or perianal disease. Cases of colitis can be particularly severe and, before the use of anti-tumor necrosis factor alpha (TNFα) therapy had become common, were reported as showing poor responsiveness to medical treatment.

CASE SUMMARY

We present the case of a 51-year-old albino woman who presented with acute severe colitis that led to the diagnosis of HPS. Histologic findings of biopsy samples showed chronic inflammation with deep ulcerations, and granulomas without caseous necrosis. Molecular genetic analysis confirmed HPS type 1, with a homozygous 27 base-pair deletion in exon 20 of the HPS1 gene. Once the patient’s bleeding diathesis was corrected by platelet transfusion, the granulomatous colitis responded dramatically to a medical treatment regimen that included corticosteroids, azathioprine and infliximab; this regimen is similar to that used in CD treatment. Although it remains unclear if the granulomatous enterocolitis in HPS is due to ceroid deposition or reflects the co-existence of CD and HPS, the fact that this case of HPS-related granulomatous colitis responded to the same therapeutic approach used in CD suggests that this type of colitis may result from HPS patients’ genetic susceptibility to CD.

CONCLUSION

We report a case of severe colitis that led to the diagnosis of HPS, which was responsive to azathioprine and infliximab.

Infantile-onset inflammatory bowel disease in a patient with Hermansky-Pudlak syndrome: a case report

BACKGROUND

Hermansky-Pudlak syndrome (HPS) is a rare, genetically heterogeneous disorder that manifests oculocutaneous albinism together with bleeding diatheses that reflect a platelet storage pool deficiency. Ten genetic subtypes of this autosomal recessive condition have been described to date. Some patients with Hermansky-Pudlak syndrome type 1, 4, or 6 develop Crohn's-like inflammatory bowel disease at any age including early childhood, but most often in adolescence or young adulthood. Here we report infantile-onset of inflammatory bowel disease in a patient with Hermansky-Pudlak syndrome type 1 who responded to infliximab.

CASE PRESENTATION

A Japanese boy, the second child of non-consanguineous healthy parents, was born with chalky white skin, silvery-white hair, and gray eyes, representing oculocutaneous albinism. He developed frequent diarrhea and fever accompanied by weight loss at 6 months, and was diagnosed with Crohn's-like inflammatory bowel disease based on the endoscopic finding of longitudinal ulcerations in the colon and the histopathologic finding of nonspecific chronic inflammation without granulomas at the age of 11 months. Treatment with an elemental diet, salazosulfapyridine, and corticosteroids failed to improve clinical or laboratory abnormalities, and the diarrhea became bloody. At 13 months he began treatment with infliximab, which produced marked improvement followed by clinical remission. Endoscopy at 20 months demonstrated healing of the colonic mucosa. At 22 months he is in sustained clinical remission receiving only infliximab. Because albinism with inflammatory bowel disease suggested Hermansky-Pudlak syndrome, we performed genetic screening using next-generation sequencing in a targeted gene panel analysis for primary immunodeficiency disease and/or inflammatory bowel disease. The patient proved to have a compound heterozygous mutation of the HPS1 gene resulting in Hermansky-Pudlak syndrome type 1.

CONCLUSIONS

We consider this report to be the first account of type 1 Hermansky-Pudlak syndrome with infantile-onset of inflammatory bowel disease. Early administration of infliximab was effective. We recommend next-generation sequencing for patients with very early-onset inflammatory bowel disease suspected to be monogenic.

Analysis of Genes Associated With Monogenic Primary Immunodeficiency Identifies Rare Variants in XIAP in Patients With Crohn's Disease

BACKGROUND & AIMS

A few rare monogenic primary immunodeficiencies (PIDs) are characterized by chronic intestinal inflammation that resembles Crohn's disease (CD). We investigated whether 23 genes associated with 10 of these monogenic disorders contain common, low-frequency, or rare variants that increase risk for CD.

METHODS

Common and low frequency variants in 1 Mb loci centered on the candidate genes were analyzed using meta-data corresponding to genotypes of approximately 17,000 patients with CD or without CD (controls) in Europe. The contribution of rare variants was assessed by high-throughput sequencing of 4750 individuals, including 660 early-onset and/or familial cases among the 2390 patients with CD. Variants were expressed from vectors in SW480 or HeLa cells and functions of their products were analyzed in immunofluorescence, luciferase, immunoprecipitation, and immunoblot assays.

RESULTS

We reproduced the association of the interleukin 10 locus with CD (P = .007), although none of the significantly associated variants modified the coding sequence of interleukin 10. We found XIAP to be significantly enriched for rare coding mutations in patients with CD vs controls (P = .02). We identified 4 previously unreported missense variants associated with CD. Variants in XIAP cause the PID X-linked lymphoproliferative disease type 2, yet none of the carriers of these variants had all the clinical features of X-linked lymphoproliferative disease type 2. Identified XIAP variants S123N, R233Q, and P257A were associated with an impaired activation of NOD2 signaling after muramyl dipeptide stimulation.

CONCLUSIONS

In a systematic analysis of variants in 23 PID-associated genes, we confirmed the association of variants in XIAP with CD. Further screenings for CD-associated variants and analyses of their functions could increase our understanding of the relationship between PID-associated genes and CD pathogenesis.

Very early onset inflammatory bowel disease

Very early onset inflammatory bowel disease (VEO-IBD) represents a unique and growing subset of patients with inflammatory bowel disease (IBD). Some VEO-IBD patients present with immunodeficiency and possess loss of function genetic mutations involving immune pathways that cause their IBD. A search for Mendelian causes of IBD is likely most beneficial when the presentation involves extra-intestinal autoimmunity or involves intestinal histopathology that is atypical for IBD. While a subset of these young patients will have highly aggressive courses (and likely present with immunodeficiency), the majority of patients with VEO-IBD appear to have disease courses similar to that of their older counterparts. Most notably, many of these young children will require long courses of immunosuppression simply as a result of the profoundly early presentation-thus increasing their long-term risks of cancer and opportunistic infections.

Hermansky-Pudlak syndrome: Report of two patients with updated genetic classification and management recommendations

Hermansky-Pudlak syndrome (HPS) is a rare autosomal recessive disorder caused by mutations in one of nine genes involved in the packaging and formation of specialized lysosomes, including melanosomes and platelet-dense granules. The cardinal features are pigmentary dilution, bleeding diathesis, and accumulation of ceroid-like material in reticuloendothelial cells. Pulmonary fibrosis induced by tissue damage is seen in the most severe forms, and one subtype is characterized by immunodeficiency. We describe two patients with HPS type 1 and review the updated gene-based classification, clinical features, and recommendations for evaluation and follow-up.

Two Complex Cases of Hermansky-Pudlak Syndrome Highlight a Potential Biologic Explanation for an Associated Crohn's Disease Phenotype

Hermansky-Pudlak syndrome (HPS) is a rare autosomal recessive disorder characterized by oculocutaneous albinism and a lack of dense granules in platelets. HPS types 1 and 4 are associated with a granulomatous enterocolitis that is phenotypically indistinguishable from Crohn's disease. We present two cases of HPS-associated Crohn's disease phenotype in which the patients were refractory to standard medical management. The pathophysiology of HPS is mediated by single-gene defects that alter endosome trafficking, and we hypothesize that this mechanism leads to the observed association with a CD phenotype.

Very early-onset inflammatory bowel disease: gaining insight through focused discovery

The pathogenesis of pediatric inflammatory bowel disease (IBD) is only partially understood. Strong evidence implicates a strong genetic component including high monozygotic twin concordance and familial disease phenotype concordance rates. Genome-wide association studies have identified associations between >160 genetic loci and the risk for developing IBD. The roles of implicated genes are largely immune-mediated, although other functions include cellular migration, oxidative stress, and carbohydrate metabolism. Additionally, growing literature describes monogenic causes of IBD that frequently present as infantile or very early-onset IBD. The interplay between IBD risk single nucleotide polymorphisms and rare genetic variants has yet to be determined. Studying patients with very early-onset IBD may elicit genetic factors that could be applied to broader populations of IBD. This review describes what is known about the genetic causes of very early-onset IBD and genetic strategies that may unravel more of the genetic causes of IBD.

Metastatic cutaneous involvement of granulomatous colitis in Hermansky-Pudlak syndrome

Hermansky-Pudlak syndrome (HPS) is a rare autosomal-recessive disorder characterized by oculocutaneous albinism, a hemorrhagic diathesis due to platelet dysfunction, and lysosomal ceroid accumulation that can cause a Crohn's-like granulomatous colitis and pulmonary fibrosis. We report peristomal and vulvar cutaneous involvement of the granulomatous colitis in HPS.

Overlap, common features, and essential differences in pediatric granulomatous inflammatory bowel disease

Overlap in the clinical presentation of pediatric granulomatous inflammatory bowel disease may be substantial, depending on the mode of presentation. Chronic granulomatous disease (CGD) may present with granulomatous colitis, perianal abscesses, hepatic abscesses or granulomas, failure to thrive, and obstruction of the gastrointestinal tract (including esophageal strictures and dysmotility, delayed gastric emptying, and small bowel obstruction). Anemia, thrombocytosis, elevated C-reactive protein and erythrocyte sedimentation rate, and hypoalbuminemia are nonspecific and may occur in any of the granulomatous inflammatory bowel diseases. In histology, macrophages with cytoplasmic inclusions will be rather specific for CGD. Sarcoidosis may present with abdominal pain or discomfort, diarrhea, weight loss, growth failure, delayed puberty, erythema nodosum, arthritis, uveitis, and hepatic granulomata. Only in 55% of the patients will angiotensin-converting enzyme be elevated. The noncaseating epithelioid granulomata will be unspecific. Bronchoalveolar lymphocytosis and abnormalities in pulmonary function are reported in sarcoidosis and in Crohn disease (CD) and CGD. Importantly, patients with CD may present with granulomatous lung disease, fibrosing alveolitis, and drug-induced pneumonitis. Sarcoidosis and concomitant gastrointestinal CD have been reported in patients, as well as coexistence of CD and sarcoidosis in siblings. Common susceptibility loci have been identified in CD and sarcoidosis. CD and CGD share defects in the defense mechanisms against different microbes. In the present review, common features and essential differences are discussed in clinical presentation and diagnostics--including histology--in CGD, sarcoidosis, and CD, together with 2 other granulomatous inflammatory bowel diseases, namely abdominal tuberculosis and Hermansky-Pudlak syndrome. Instructions for specific diagnosis and respective treatments are provided.

Crohn's disease: an immune deficiency state

Crohn's disease is a chronic inflammatory disorder primarily affecting the gastrointestinal tract. Its clinical manifestations arise from a substantial infiltration of the intestinal mucosa by activated leukocytes and the downstream consequences of chronic inflammation. The underlying cause driving this immunological reaction remains poorly understood. A number of hypotheses have been proposed, most of which postulate a primary over-activation of the immune response, based on the pathological appearances of active Crohn's lesions. Interestingly, none of these theories have been mechanistically proven. It is possible that the immunological events responsible for disease initiation are quite different from those contributing to its persistence and propagation. A substantial body of data has emerged in recent years to suggest that the primary defect in Crohn's disease is actually one of relative immunodeficiency. This review considers the evidence for such a phenomenon in contrast to alternative prevailing hypotheses and attempts to address some of the potential paradoxes that it generates.

Gastrointestinal manifestations in primary immune disorders

The gastrointestinal tract is the largest lymphoid organ in the body containing T and B lymphocytes, macrophages, and dendritic cells. Despite the fact that these cells are constantly confronted with antigen primarily in the form of food and bacteria, immune responses in the gut are tightly regulated to maintain homeostasis. Without this balance of active immunity and tolerance, mucosal inflammation may ensue, and manifest as Crohn's disease, ulcerative colitis, pernicious anemia, or celiac sprue. Therefore, it is not unreasonable that inflammatory diseases of the gut are commonly encountered in patients with primary immune deficiencies. The exact pathogenesis of gastrointestinal diseases in the setting of primary immunodeficiency remains unknown, however, both humoral and cell-mediated immunity appear to play a role in preventing intestinal inflammation. Patients presenting with atypical gastrointestinal disease and/or failure to respond to conventional therapy should be evaluated for an underlying primary immune disorder in order to initiate appropriate treatment, such as immunoglobulin or in more severe cases bone marrow transplantation, to prevent long term complications.

Phagocyte dysfunction and inflammatory bowel disease

Inflammatory bowel diseases are common chronic inflammatory disorders. The majority are idiopathic and can be broadly divided into Crohn's disease and ulcerative colitis. Their cause is unknown, but most hypotheses focus on a primary role for T-cell dysfunction. Conversely, there is a collection of congenital disorders of phagocyte function that result not only in immunodeficiency but also in noninfectious inflammatory bowel disease. In all cases, the latter is strikingly reminiscent of the clinical and pathological features of Crohn's disease. This coincides with recent work demonstrating that despite previous emphasis on adaptive immune dysfunction, patients with Crohn's disease actually possess an unusually weak acute innate inflammatory response. This review consolidates the literature on inflammatory bowel disease in congenital immunodeficiencies and considers the role of phagocyte dysfunction in Crohn's disease. Concepts about pathogenesis and treatment that can be carried across these disorders are also discussed.

Complicated Crohn's-like colitis, associated with Hermansky-Pudlak syndrome, treated with Infliximab: a case report and brief review of the literature

Introduction

Hermansky-Pudlak syndrome (HPS) is a rare autosomal recessive inherited disorder consisting of a triad of albinism, increased bleeding tendency secondary to platelet dysfunction, and systemic complications associated with ceroid depositions within the reticuloendothelial system. HPS has been associated with gastrointestinal (GI) complications related to chronic granulomatous colitis with pathologic features suggestive of Crohn's disease. This colitis can be severe and has been reported to be poorly responsive to medical therapies including antibiotics, corticosteroids, sulfasalazine, mesalamine and azathioprine.

Case presentation

We report a patient with HPS which was complicated by inflammatory bowel disease with clinical and pathologic features of Crohn's disease, refractory to antibiotics, corticosteroids and azathioprine. A trial of infliximab was attempted and repeated infusions produced a complete response.

Conclusion

The occurrence of ileitis and perianal lesions and also the histopathological findings in our case suggest that HPS and Crohn's disease may truly be associated. Given this similarity and the failure of the standard medical therapy of corticosteroids and azathioprine, our patient received infliximab with marked clinical improvement.

Crohn’s disease: Innate immunodeficiency?

In the past, Crohn’s disease (CD) has been understood primarily as an immunologic disorder characterized by an abnormal T-cell response. Recent in vitro and in vivo data suggests that CD may instead be precipitated by innate immune dysfunction resulting from a combination of genetic and environmental factors. Some reports have demonstrated a defective immune response in a variety of other cellular components, including neutrophils, monocytes and dendritic cells. Recent studies of granulocyte-macrophage colony-stimulating factor (GM-CSF) in CD, aiming to stimulate the innate immune system with the conception that an innate immune defect underlies the development of the disease, have been demonstrated a clinical benefit and reinforce this evolving understanding of the disease.