Perttu Arkkila’s research while affiliated with University of Helsinki and other places

Purpose Several laboratory tests are used to monitor disease activity and possible complications in patients with inflammatory bowel disease (IBD). Due to limited resources, it is important to identify patients who benefit the most from tight laboratory testing and follow-up. We sought to assess the correlation between a symptom-based clinical activity index and commonly monitored laboratory tests in a large patient population. Methods The Finnish IBD registry records a validated IBD symptom index questionnaire (IBD-SI) that measures disease activity and the influence of IBD on daily life in patients with ulcerative colitis (UC) and Crohn’s disease (CD). The activity index was compared with the commonly measured laboratory values of fecal calprotectin (FC), hemoglobin (Hb), ferritin, and C-reactive protein (CRP). Results A total of 5044 IBD patients with 171,967 activity index measurement pairs were included. FC, Hb, and CRP correlated significantly with the activity index in both UC (Spearman’s r 0.383, −0.212, 0.175; p < 0.001) and CD (Spearman’s r 0.156, −0.176, 0.152; p < 0.001). No correlation between the activity index and ferritin (Spearman’s r 0.038 [UC], 0.005 [CD]; p = 0.020, p = 0.825) was found. Conclusion The activity index is a useful tool in the assessment of IBD activity. Active or inactive disease can be identified better, which may be beneficial in planning more personalized follow-up strategies. Tight monitoring of disease can be better targeted to the correct patient population, and the onset of disease flare may be caught at an earlier stage.

Background Clostridioides difficile infection (CDI) is a clinical challenge associated with poor outcomes in patients with inflammatory bowel disease (IBD). Objectives To identify clinical risk factors for CDI and its recurrence among patients with IBD. Design Case–control cohort study of IBD patients with and without episodes of CDI. Methods A case–control study of 279 IBD patients with CDI. Medical history and IBD-related symptoms 3 months preceding a toxin-positive CDI were recorded and compared with age- and sex-matched IBD patients without CDI. Outcomes of CDI in IBD patients were recorded 2–6 months after CDI. Results Based on clinical symptoms and fecal calprotectin levels, IBD is active before CDI. Recently diagnosed IBD seemed to increase the risk for CDI. Corticosteroid usage frequently preceded CDI episodes. Advanced therapies were not associated with CDI. Antibiotic intake was not registered before CDI in 30% of the episodes. Recurrent CDI (rCDI) occurred in 30% (84/279) of IBD-CDI patients and 67% (90/135) of those episodes were registered within 90 days from the preceding episode. Most (79%) rCDI patients had ulcerative colitis (UC). CDI could complicate underlying IBD by increasing the need for escalation in IBD-related medical therapy and leading to hospitalization but it did not seem to increase the risk of colectomy. Conclusion The major risk factors associated with CDI in IBD patients were IBD activity before infection, UC and colonic Crohn’s disease, short duration of IBD, corticosteroid usage, and hospitalization. Patients with active IBD and a shorter disease duration may benefit from more frequent follow-ups in the early stages, as they appear to be at higher risk of developing CDI.

Background Recent studies suggest that subcutaneous infliximab is effective and safe for treating patients with inflammatory bowel disease. Real-world studies with larger cohorts are needed to confirm the efficacy of subcutaneous treatment. Aims The aim was to assess real-world treatment persistence, clinical outcomes, infliximab concentrations, and treatment safety after switching from intravenous to subcutaneous infliximab treatment with patients with inflammatory bowel disease. Methods This retrospective register-based study included patients with inflammatory bowel disease who were in clinical remission and switched from intravenous infliximab maintenance therapy to subcutaneous infliximab in two tertiary centers. Results A total of 274 patients (104 Crohn's disease and 170 ulcerative colitis) were included. After the switch, the treatment persistence at 12 months was 94.8% in patients with Crohn’s disease and 88.8% in patients with ulcerative colitis. Only 11.3% (n = 31) of the patients discontinued the treatment during 79-week median follow-up. Compared to the baseline, no change occurred in clinical disease activity at the time points of 3, 6, and 12 months, based on the Harvey–Bradshaw Index or partial Mayo Score (p = 0.792 and p = 0.426, respectively). Infliximab median concentrations were higher (p < 0.0001) during subcutaneous treatment (16.75 µg/ml) compared to the intravenous treatment median trough levels before the switch (6.71 µg/ml). In total, 15.0% (n = 41) of the patients reported adverse events. Conclusion Switching to subcutaneous infliximab maintenance therapy was associated with high treatment persistence, a stable disease course, increased infliximab concentrations, and an acceptable safety profile.

Lääketieteellinen Aikakauskirja Duodecim 2025;141(4):291-9

Background and Aim Esophageal duplication cysts (EDCs) are rare congenital malformations, often discovered incidentally during endoscopy or on computed tomography (CT) scans. The role of endoscopic ultrasound (EUS) and CT scan in the diagnosis of these lesions and indications for surgical treatment are underreported. The aim of this study was to investigate these topics in a cohort of patients. Materials and Methods Between January 2001 and October 2020, 82 patients had a suspicion of esophageal duplication cyst on endoscopic ultrasound. Thirty four of these patients were referred for surgical enucleation of the lesion, but three patients were lost to follow-up. At the end, 31 patients, who underwent surgical treatment for their suspected EDC were included in this study. Clinical features, EUS findings, CT images, surgical treatment, and outcome were collected from hospital health records. CT images were re-evaluated by a chest radiologist. Type of surgery, surgical complications, and final histological diagnosis were reported. Results and Conclusion The patients referred for surgery were younger (p = 0.0001) and had larger lesions (> 2 cm; p = 0.005) than the patients who had non-operative follow-up. From thirty-one operated patients, eighteen (58%) had post-operative histological diagnosis of duplication cyst. On EUS the final histological diagnosis was correct in 58% (18/31) of all the operated cases and on CT scan 57% (17/30). CT scan misdiagnosed three of the EDCs but found two leiomyomas correctly. None of these patients developed malignancy. According to this study, neither EUS without fine-needle biopsy nor CT scan alone can differentiate EDCs from other mediastinal masses.

Imbalanced microbiota may contribute to the pathophysiology of irritable bowel syndrome (IBS), thus fecal microbiota transplantation (FMT) has been suggested as a potential treatment. Previous studies on the relationship between clinical improvement and microbiota after FMT have been inconclusive. In this study, we used 16S rRNA gene amplicon and shotgun metagenomics data from a randomized, placebo controlled FMT trial on 49 IBS patients to analyze changes after FMT in microbiota composition and its functional potential, and to identify connections between microbiota and patients’ clinical outcome. As a result, we found that the successful modulation of microbiota composition and functional profiles by FMT from a healthy donor was not associated with the resolution of symptoms in IBS patients. Notably, a donor derived strain of Prevotella copri dominated the microbiota in those patients in the FMT group who had a low relative abundance of P. copri pre-FMT. The results highlight the multifactorial nature of IBS and the role of recipient’s microbiota in the colonization of donor’s strains.