{
  "abstract": "Infliximab, a chimeric monoclonal antibody targeting tumour necrosis factor-alpha (TNF-α), is widely used in inflammatory bowel disease (IBD). While effective, it carries the risk of uncommon but serious adverse effects, including pulmonary and hepatic injury. We report a rare paediatric case of suspected infliximab-related pneumonitis with concurrent hepatotoxicity.A teenager diagnosed with IBD-unclassified was started on infliximab two months after diagnosis on an accelerated induction regimen due to recurrent flare-ups. Azathioprine was paused for hepatotoxicity but later reintroduced at a low dose, then discontinued for intolerance, after which mercaptopurine was started. The liver function tests subsequently normalised.Six months later, during a routine infliximab infusion visit, the patient developed acute respiratory distress with hypoxaemia. Chest radiography revealed bilateral diffuse opacification (figure 1), and CT thorax showed symmetrical consolidation of the lower lobes without cavitation or effusion. Bronchoalveolar lavage cultures were negative, including for mycobacterium tuberculosis. Despite prolonged intravenous antibiotics and antifungals, hypoxia persisted, and infection was excluded. Pulmonary function testing revealed severe restriction, gradually improving with corticosteroid therapy.Given the lack of infectious aetiology, inflammatory or hypersensitivity pneumonitis secondary to infliximab was diagnosed. A lung biopsy was considered; however, the procedure was deferred as the patient was clinically unstable and required high-flow oxygen support.The patient received three days of intravenous methylprednisolone followed by oral tapering prednisolone and prophylactic azithromycin. Infliximab was discontinued, and Vedolizumab initiated as a gut-selective alternative.During admission, transaminase elevations and mild coagulopathy were noted. Abdominal ultrasound demonstrated a starry sky hepatic pattern. The tertiary hepatology team considered drug-induced liver injury but recommended a comprehensive workup to exclude other causes, including autoimmune, infectious, and metabolic aetiologies. All investigations were unremarkable, supporting a diagnosis of infliximab-related hepatotoxicity.The mechanism of infliximab-associated hepatotoxicity is believed to involve autoimmune or immuno-allergic reactions rather than direct hepatocyte injury. According to LiverTox, Infliximab has been linked to several hepatic injury patterns—most commonly autoimmune-type hepatitis due to immune dysregulation and antibody formation, rather than intrinsic hepatotoxicity.1 Similarly, pulmonary injury associated with TNF-α inhibitors is thought to result from drug-induced immune activation and hypersensitivity.This case highlights a rare but important dual complication of infliximab therapy in a paediatric patient—pneumonitis and hepatotoxicity—occurring in the absence of other identifiable causes. The temporal association, exclusion of infection, radiological findings, and favourable response to corticosteroids support the diagnosis.Pulmonary complications of TNF-α inhibitors are uncommon but increasingly recognised. Recent pharmacovigilance data from the World Health Organization’s VigiBase indicate that infliximab shows one of the strongest associations with drug-induced interstitial lung disease among biologic agents.2 Moreover, detailed case reports document infliximab-induced pneumonitis and organising pneumonia in patients with IBD or other inflammatory conditions.3 4 In this patient, the clinical presentation, imaging features and rapid corticosteroid response are consistent with drug-induced pneumonitis rather than an infectious process. Early multidisciplinary intervention, prompt discontinuation of the offending agent, and the initiation of corticosteroid therapy were essential for recovery. Transitioning to a gut-selective biologic enabled continued IBD control while minimising risk of further systemic immune-mediated lung injury.References Infliximab. In: LiverTox: Clinical and Research Information on Drug-Induced Liver Injury [Internet]. Bethesda (MD): National Institute of Diabetes and Digestive and Kidney Diseases; 2012–. Available from: https://www.ncbi.nlm.nih.gov/books/NBK548203/Minagi A, Nawa H, Goda M. Evaluation of interstitial lung disease complications caused by biologic agents using a spontaneous adverse drug reaction reporting database. Pharmacol Res Perspect 2025;13:e70063.Makkawy EA, Alanazi MT, Yehia MF. Infliximab-induced interstitial pneumonitis: a case report. Cureus 2023;15:e40812.Pham K, Wysham N. Infliximab-induced organising pneumonia resulting in persistent respiratory impairment. ACG Case Rep J. 2025;12:e01855.Abstract OC111 Figure 1Chest radiograph demonstrating bilateral diffuse pulmonary opacification",
  "authors": [
    {
      "affiliations": [
        "University Hospitals of Leicester NHS Trust"
      ],
      "name": "Shafeeqa Gulam Khader"
    },
    {
      "affiliations": [
        "University Hospitals of Leicester NHS Trust"
      ],
      "name": "Rajiv Mohan"
    }
  ],
  "title": "OC111 A case report on Infliximab related pneumonitis and hepatotoxicity in a paediatric patient with inflammatory bowel disease",
  "uid": "7d8cfc0e-f008-51fb-9e67-fd50ff647dd8"
}