Review article: pathogenesis and clinical manifestations of gastrointestinal involvement in systemic sclerosis

Colonic and Anorectal Manifestations of Systemic Sclerosis

PURPOSE OF REVIEW

Systemic sclerosis is a chronic autoimmune disorder commonly involving the gastrointestinal tract, including the colon and anorectum. In this review, we summarize major clinical manifestations and highlight recent developments in physiology, diagnostics, and treatment.

RECENT FINDINGS

The exact pathophysiology of systemic sclerosis is unclear and likely multifactorial. The role of the microbiome on gastrointestinal manifestations has led to a better understanding of potential pathogenic gut flora. Carbohydrate malabsorption is common. Evaluation using fecal calprotectin and high-resolution anorectal manometry may broaden our understanding of the etiologies of diarrhea and fecal incontinence and help with early recognition of pathology. Prucalopride, a high-affinity 5HT₄ agonist, and pyridostigmine, an acetylcholinesterase inhibitor, may help improve colonic transit in patients with constipation. Intravenous immunoglobulins have been used to target muscarinic receptor antibodies that are believed to contribute to gastrointestinal dysmotility. Colonic and anorectal manifestations of systemic sclerosis include constipation, diarrhea, and fecal incontinence, and can diminish quality of life for these patients. Recent studies regarding pathophysiology as well as diagnostic and treatment options are promising. Further targeted studies to facilitate early intervention and better management of refractory symptoms are still needed.

Radiological findings in gastrointestinal scleroderma

Gastrointestinal involvement is the most common visceral organ manifestation in systemic sclerosis. Symptoms from the gastrointestinal tract are very frequent among scleroderma patients and in many cases present a therapeutic challenge. However, gastrointestinal involvement may also be asymptomatic, presenting with complications later in the disease course. Early recognition of gastrointestinal scleroderma is therefore important both for symptomatic control and prevention of complications. Gastrointestinal imaging alongside clinical assessment forms the mainstay of diagnosis. Radiological investigations, traditionally plain radiographs and barium studies, with the more recent advances in computed tomography, magnetic resonance imaging and ultrasound, provide means for accurate evaluation of visceral organ involvement and more effective patient care. Awareness of the characteristic images is important not only for radiologists but also for the treating physicians and gastroenterologists.

Perspectives on the interlinked nature of systemic sclerosis and reflux disease

Systemic sclerosis (SSc) is a multisystem connective tissue disease, characterized by chronic inflammation and vascular changes that result in esophageal smooth muscle atrophy and fibrosis. Subsequent progressive loss of peristalsis in the distal esophagus and loss of lower esophageal sphincter function lead to problems with the protective barrier and exposure of sensitive tissues to the gastroduodenal contents, a disorder called reflux disease. Areas covered: Depending on the range, nature and symptoms of the disease, the term 'reflux disease' may refer to gastroesophageal reflux, laryngopharyngeal reflux, microaspiration into the airways and silent reflux. Despite the links between these visceral complications, this connection remains controversial. This is due to a lack of complete understanding, the asymptomatic nature of the disease and the limited diagnostic accuracy of tests, which can delay diagnosis. Such delays are problematic, given that the early detection of GERD in SSc patients, the timing of assessment, the treatment of the organs involved are critical aspects of patient prognosis and disease outcome. Expert commentary: This review summarizes the most recent knowledge about the pathophysiology, diagnosis and prospective treatment of GERD in SSc patients and highlights how innovative technologies applied through an integrative, interdisciplinary approach may soon lead to effective treatment strategies.

Small intestinal bacterial overgrowth in systemic sclerosis: a review of the literature

Systemic sclerosis (SSc) is a chronic, connective tissue disease with an autoimmune pattern characterized by inflammation, fibrosis and microcirculation changes leading to internal organs malfunctions. Recently, the presence of uncharacteristic gastrointestinal symptoms in the course of SSc has been underlined. The possible cause of such clinical presentation is the small intestinal bacterial overgrowth (SIBO). Nevertheless, these manifestations resulting from gastrointestinal tract hypomotility may occur in numerous disease entities. The systematic review of the literature was performed on MEDLINE database using the relevant MeSH terms including all sub-headings. After further investigation, the initial number of 56 records was limited to 7 results. The study analysis showed an increased presence of SIBO in 39% of patients suffering from SSc. The average SSc duration was longer in SSc patients with coexisting SIBO. SIBO remains a diagnostic and therapeutic challenge and therefore is a significant clinical problem among patients suffering from SSc.

Gastrointestinal and Hepatic Disease in Systemic Sclerosis

Although classification criteria for systemic sclerosis (SSc) do not incorporate gastrointestinal tract (GIT) manifestations often present in this disease, the GIT is the most common internal organ involved. Pathophysiology of GIT involvement is thought to be similar to other organs in SSc with fibroproliferative vascular lesions of small arteries and arterioles, increased production of profibrotic growth factors, and alterations of innate, humoral, and cellular immunity. These processes result in neuropathy progressing to myopathy with eventual fibrosis. Proper diagnostics and therapeutics for SSc-GIT involvement require the treating physician to have an understanding of an integrated approach and potential medication adverse effects.

Critical Roles of microRNAs in the Pathogenesis of Fatty Liver: New Advances, Challenges, and Potential Directions

In this review, we summarize the current understanding of microRNA (miRNA)-mediated modulation of the gene expression in the fatty liver as well as related signaling pathways. Because of the breadth and diversity of miRNAs, miRNAs may have a very wide variety of biological functions, and much evidence has confirmed that miRNAs are involved in the pathogenesis of fatty liver. In the pathophysiological mechanism of fatty liver, miRNAs may be regulated by upstream regulators, and have their own regulatory targets. miRNAs display important roles in the pathological mechanisms of alcoholic liver disease and non-alcoholic fatty liver disease. At present, most of the miRNA studies are focused on cell and tissue levels, and in vivo studies will help us elucidate the regulation of miRNAs and help us evaluate the potential of miRNAs as diagnostic markers and therapeutic targets. Furthermore, there is evidence that miRNAs are involved in the mechanism of natural medicine treatment in fatty liver. Given the important roles of miRNAs in the pathogenesis of fatty liver, we predict that studies of miRNAs in the pathogenesis of fatty liver will contribute to the elucidation of fatty liver pathology and the treatment of fatty liver patients.

Systemic sclerosis and sarcoidosis: a rare case of chronic intestinal pseudo-obstruction

The coexistence of systemic sclerosis (SSc) and sarcoidosis is an extremely rare phenomenon; some studies question its existence. We report the case of a male with a diagnosis of sarcoidosis that was admitted due to abdominal distension and pain. After a thorough investigation, he was diagnosed with severe chronic intestinal pseudo-obstruction as a manifestation of SSc.

Gastrointestinal Manifestations of Systemic Sclerosis

Systemic sclerosis (SSc) is a rare autoimmune disease characterized by fibroproliferative alterations of the microvasculature leading to fibrosis and loss of function of the skin and internal organs. Gastrointestinal manifestations of SSc are the most commonly encountered complications of the disease affecting nearly 90% of the SSc population. Among these complications, the esophagus and the anorectum are the most commonly affected. However, this devastating disorder does not spare any part of the gastrointestinal tract (GIT), and includes the oral cavity, esophagus, stomach, small and large bowels as well as the liver and pancreas. In this review, we present the current understanding of the pathophysiologic mechanisms of SSc including vasculopathy, endothelial to mesenchymal transformation as well as the autoimmune pathogenetic pathways. We also discuss the clinical presentation and diagnosis of each part of the GIT affected by SSc. Finally, we highlight the latest developments in the management of this disease, addressing the severe malnutrition that affects this vulnerable patient population and ways to assess and improve the nutritional status of the patients.

Pyridostigmine for the treatment of gastrointestinal symptoms in systemic sclerosis

BACKGROUND/PURPOSE

Symptoms of gastrointestinal dysmotility are common among patients with systemic sclerosis (SSc), and the management of severe cases is often limited by a relative lack of effective interventions. The objective of this case series was to review our experience with pyridostigmine as a treatment for patients with SSc and symptomatic gastrointestinal disease.

METHODS

This study evaluated rates of symptom improvement, side effects, medication adherence, and dose ranges for SSc patients prescribed pyridostigmine for refractory gastrointestinal symptoms over a 10-year period at a quaternary referral center. Patients were defined as responders if they remained on pyridostigmine for at least 4 weeks and clinical benefit was documented by the recorded response of the patient or by the treating physician RESULTS: Of 31 patients treated with pyridostigmine for at least 4 weeks, 51.6% reported symptomatic improvement. Constipation was the most commonly improved symptom based on prevalence prior to therapy (noted by 6/20 patients suffering with constipation). Fifteen of 31 patients reported adverse effects, most commonly diarrhea. Throughout the duration of follow-up (median 126 days, range: 28-506 days), pyridostigmine was continued by 81.3% of patients who reported symptomatic benefit and 58.1% of patients overall.

CONCLUSIONS

Pyridostigmine holds promise for the treatment of various gastrointestinal symptoms in SSc patients, particularly in patients with refractory constipation. Though side effects may limit its use, most patients who experienced benefit chose to continue therapy.

Transforming growth factor-β signaling in systemic sclerosis

Systemic sclerosis (SSc) is a complex, multiorgan autoimmune disease of unknown etiology. Manifestation of the disease results from an interaction of three key pathologic features including irregularities of the antigen-specific immune system and the non-specific immune system, resulting in autoantibody production, vascular endothelial activation of small blood vessels, and tissue fibrosis as a result of fibroblast dysfunction. Given the heterogeneity of clinical presentation of the disease, a lack of universal models has impeded adequate testing of potential therapies for SSc. Regardless, recent research has elucidated the roles of various ubiquitous molecular mechanisms that contribute to the clinical manifestation of the disease. Transforming growth factor β (TGF-β) has been identified as a regulator of pathological fibrogenesis in SSc. Various processes, including cell growth, apoptosis, cell differentiation, and extracellular matrix synthesis are regulated by TGF-β, a type of cytokine secreted by macrophages and many other cell types. Understanding the essential role TGF-β pathways play in the pathology of systemic sclerosis could provide a potential outlet for treatment and a better understanding of this severe disease.