Henoch-Schönlein purpura associated with helicobacter pylori infection: the pathogenic roles of IgA, C3, and cryoglobulins?

Recalcitrant intussusception: exploring potential associations with Helicobacter pylori infection - a case report and literature review

BACKGROUND

Intussusception, a common cause of abdominal pain in children, often lacks clear underlying causes and is mostly idiopathic. Recurrence, though rare, raises clinical concerns, with rates escalating after each episode. Factors like pathological lead points and Henoch-Schönlein purpura (HSP) are associated with recurrent cases. On the other hand, the prevalence of Helicobacter pylori (H. pylori), often asymptomatic, in children has been declining. Although its infection is reported to be linked with HSP, its role in recurrent intussusception remains unexplored. Further research is needed to understand the interplay among H. pylori (culprit pathogen), HSP (trigger), and intractable intussusception so as to develop effective management strategies.

CASE PRESENTATION

A two-year-old girl experienced four atypical episodes of intussusception at distinct locations, which later coincided with HSP. Despite treatment with steroids, recurrent intussusception persisted, suggesting that HSP itself was not a major cause for intractable presentations. Subsequent identification of H. pylori infection and treatment with triple therapy resulted in complete resolution of her recalcitrant intussusception.

CONCLUSION

This instructive case underscored a sequence wherein H. pylori infection triggered HSP, subsequently resulting in recurrent intussusception. While H. pylori infection is not common in young children, the coexistence of intractable intussusception and steroid-resistant recurrent HSP necessitates consideration of H. pylori infection as a potential underlying pathogen.

IgA Vasculitis: Etiology, Treatment, Biomarkers and Epigenetic Changes

IgA, previously called Henoch-Schönlein vasculitis, is an essential immune component that drives the host immune response to the external environment. As IgA has the unique characteristic of a flexible response to broad types of microorganisms, it sometimes causes an autoreactive response in the host human body. IgA vasculitis and related organ dysfunction are representative IgA-mediated autoimmune diseases; bacterial and viral infections often trigger IgA vasculitis. Recent drug developments and the presence of COVID-19 have revealed that these agents can also trigger IgA vasculitis. These findings provide a novel understanding of the pathogenesis of IgA vasculitis. In this review, we focus on the characteristics of IgA and symptoms of IgA vasculitis and other organ dysfunction. We also mention the therapeutic approach, biomarkers, novel triggers for IgA vasculitis, and epigenetic modifications in patients with IgA vasculitis.

Differential expression of long non-coding RNA and mRNA in children with Henoch-Schönlein purpura nephritis

Long non-coding RNAs (lncRNAs) serve an essential role in regulating immunological functions. However, their impact on Henoch-Schönlein purpura nephritis (HSPN), has remained elusive. The present study determined the expression of lncRNAs and mRNAs in the peripheral blood of 6 children with HSPN and recruited 4 healthy children for comparative study. High-throughput sequencing revealed outstanding differences in lncRNA and mRNA expression, which were verified through reverse transcription-quantitative polymerase chain reaction. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses were used to investigate the associated biological functions and possible mechanisms of lncRNAs and mRNAs in HSPN. A total of 820 differentially expressed lncRNAs between the two groups were identified, of which 34 were upregulated and 786 were downregulated. Simultaneously, a total of 3,557 mRNAs were also identified to be differentially expressed, of which 1,232 were upregulated and 2,325 were downregulated. The results revealed that the expression of lncRNAs including ENST00000378432, ENST00000571370, uc001kfc.1 and uc010qna.2 was decreased in HSPN patients compared with that in healthy controls. These lncRNAs were associated with the p53 signaling pathway and apoptosis-associated genes (AKT2, tumor protein 53, phosphatase and tensin homolog and FAS). Further studies of those lncRNAs will be performed to elucidate their functions in apoptosis. Complete raw data files were deposited in the Gene Expression Omnibus (GEO) at National Center for Biotechnology information under the GEO accession no. GSE102114 (www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE102114).

Hematologic manifestations of Helicobacter pylori infection

Helicobacter pylori (H. pylori) is the most common infection in humans, with a marked disparity between developed and developing countries. Although H. pylori infections are asymptomatic in most infected individuals, they are intimately related to malignant gastric conditions such as gastric cancer and gastric mucosa-associated lymphoid tissue (MALT) lymphoma and to benign diseases such as gastritis and duodenal and gastric peptic ulcers. Since it was learned that bacteria could colonize the gastric mucosa, there have been reports in the medical literature of over 50 extragastric manifestations involving a variety medical areas of specialization. These areas include cardiology, dermatology, endocrinology, gynecology and obstetrics, hematology, pneumology, odontology, ophthalmology, otorhinolaryngology and pediatrics, and they encompass conditions with a range of clear evidence between the H. pylori infection and development of the disease. This literature review covers extragastric manifestations of H. pylori infection in the hematology field. It focuses on conditions that are included in international consensus and management guides for H. pylori infection, specifically iron deficiency, vitamin B₁₂ (cobalamin) deficiency, immune thrombocytopenia, and MALT lymphoma. In addition, there is discussion of other conditions that are not included in international consensus and management guides on H. pylori, including auto-immune neutropenia, antiphospholipid syndrome, plasma cell dyscrasias, and other hematologic diseases.

Helicobacter pylori and skin autoimmune diseases

Autoimmune skin diseases are characterized by dysregulation of the immune system resulting in a loss of tolerance to skin self-antigen(s). The prolonged interaction between the bacterium and host immune mechanisms makes Helicobacter pylori (H. pylori) a plausible infectious agent for triggering autoimmunity. Epidemiological and experimental data now point to a strong relation of H. pylori infection on the development of many extragastric diseases, including several allergic and autoimmune diseases. H. pylori antigens activate cross-reactive T cells and induce autoantibodies production. Microbial heat shock proteins (HSP) play an important role of in the pathogenesis of autoimmune diseases because of the high level of sequence homology with human HSP. Eradication of H. pylori infection has been shown to be effective in some patients with chronic autoimmune urticaria, psoriasis, alopecia areata and Schoenlein-Henoch purpura. There is conflicting and controversial data regarding the association of H. pylori infection with Behçet's disease, scleroderma and autoimmune bullous diseases. No data are available evaluating the association of H. pylori infection with other skin autoimmune diseases, such as vitiligo, cutaneous lupus erythematosus and dermatomyositis. The epidemiological and experimental evidence for a possible role of H. pylori infection in skin autoimmune diseases are the subject of this review.

Is Helicobacter pylori infection associated with Henoch-Schonlein purpura in Chinese children? a meta-analysis

BACKGROUND

The prevalence of Helicobacter pylori (H. pylori) infection is high in China. It not only causes the damage of gastric epithelium, but also plays a potential pathogenic role in several extraintestinal diseases. Henoch-Schonlein purpura (HSP) is one of the most common vasculitis syndromes affecting children. Although its cause is unclear, HSP is often considered to be associated with infectious agents. This metaanalysis of previously published studies was conducted using a predefined protocol to evaluate the underlying association between H. pylori infection and HSP in Chinese children.

METHODS

Predefined search strategy and inclusion criteria were set up to select studies reporting the prevalence of H. pylori infection among HSP children and control groups. Included studies were subjected to quality assessment and data extraction by two independent reviewers. The pooled odds ratio (OR) was calculated as the effect size via both traditional and cumulative meta-analysis. Heterogeneity was investigated by subgroup analysis, and the nonparametric "trim and fill" method was performed to adjust the overall estimate for the existence of publication bias.

RESULTS

Ten eligible studies covering 749 HSP children and 560 controls were included for metaanalysis. Observational epidemiology studies clearly aimed at detecting the potential association between H. pylori infection and HSP with retrospective data collection from the children enrolled consecutively. Overall, 49.27% (369/749) of HSP children had evidence of H. pylori infection compared with 23.39% (131/560) of children in the control group. The pooled OR of H. pylori infection in HSP children (10 studies with 749 HSP children) was 3.80 [95% confidence interval (CI): 2.54-5.68, P<0.001], and the overall estimate from the cumulative meta-analysis confirmed the association with more narrow confidence interval (OR=3.35, 95% CI: 2.95-3.81). In HSP children mainly with abdominal manifestations (8 studies with 337 HSP children), the pooled OR was 4.62 (95% CI: 2.66-8.01, P<0.001). The adjusted pooled OR was 2.04 (95% CI: 1.48-2.82, P<0.001), determined by the nonparametric "trim-andfill" method for eliminating the effect of publication bias. H. pylori eradication therapy (4 studies with 266 HSP children) was capable of reducing the recurrence of HSP (RR=0.38, 95% CI: 0.25-0.58, P<0.001). Although the subgroup analysis for heterogeneity suggested that diagnostic methods and geographical diversity might be account for the heterogeneity, statistical analysis of differences revealed no differences between subgroups, indicating their limited impact on the overall estimates.

CONCLUSIONS

These results suggest the necessity of screening H. pylori infection in HSP children, particularly in those with gastrointestinal manifestations in China. Eradication therapy may reduce the recurrence of HSP in children with H. pylori infection. However, further mechanistic and more clinical studies in different populations and regions are needed to confirm this association and the effect of eradication of H. pylori in HSP children.