From Hypersensitivity Pneumonitis to Lung Adenocarcinoma: A Case Report Illustrating Diagnostic Complexity

Our plain-English summary of From Hypersensitivity Pneumonitis to Lung Adenocarcinoma: A Case Report Illustrating Diagnostic Complexity, by U.K. Pabani, S. Visvalingam, K. Jones, et al (Curēus, 2025).

The study

• Authors: U.K. Pabani, S. Visvalingam, K. Jones, A. Sidky, M. Rasoul
• Journal: Curēus
• Published: 2025;17(8):e89584
• Type of article: Case report
• Read it: PubMed · Publisher · Free full text

Abstract

Adenocarcinoma of the lung is the most common type of lung cancer and is classified as one of the non-small cell lung cancers. It typically arises in the peripheral regions of the lungs, affecting the dense glandular tissues. Most patients diagnosed with pulmonary adenocarcinoma are current or former smokers and present with nonspecific respiratory symptoms such as a persistent cough and shortness of breath. Many also go on to develop B symptoms, including weight loss and night sweats. We present a case of an 84-year-old Caucasian woman, a lifelong nonsmoker and teetotaller, who presented with a two-week history of dry cough, shortness of breath, and chest heaviness following receipt of her influenza vaccination. Her past medical history included hypertension (treated with amlodipine and perindopril), glaucoma, and bilateral cataracts. Initial blood tests showed normal infection and inflammatory markers. However, her chest X-ray was suggestive of pulmonary fibrosis, with fibrotic changes predominantly in the bilateral lower lung zones. She was initially treated with a tapering course of prednisolone for suspected hypersensitivity pneumonitis. Lung function tests were arranged, and a computed tomography chest scan revealed tiny centrilobular nodules in both lungs, located in peribronchovascular, perifissural, and subpleural areas. Further history revealed regular exposure to a Western Rosella bird. She denied dampness, mold, or known asbestos exposure at home. Connective tissue disease screening and avian precipitins, however, were negative. She later presented again with worsening symptoms. Arterial blood gas analysis revealed type 1 respiratory failure. The patient was admitted to the intensive care unit and was intubated and ventilated. A repeat chest X-ray showed progressive parenchymal changes without regression. Intravenous 500 mg of methylprednisolone was started; however, she showed no improvement with it. The patient's case was discussed at the lung multidisciplinary team meeting, and a lung biopsy was recommended, which was carried out via bronchoscopy. Histopathology revealed fragmented cores of adenocarcinoma with lepidic and papillary growth patterns, mucinous type, consistent with a primary lung origin (T4N0M1a). The patient's condition continued to deteriorate despite intensive care support, and she sadly passed away two weeks after admission. This case underscores the need to maintain a broad differential diagnosis, particularly in patients who fail to improve with treatment. It also emphasizes the role of biopsy in resolving the diagnostic challenge, as imaging studies did not provide a clear diagnosis.

Copyright © 2025, Pabani et al.

In plain English

This case report, by doctors in England, describes an 84-year-old Caucasian woman who had never smoked and had no known asbestos exposure. She went to hospital with two weeks of dry cough, breathlessness and chest heaviness that began after her annual flu vaccination. Her chest X-ray showed nodules throughout both lungs, and a CT scan showed many small nodules, mostly in the lower lobes. She regularly looked after a Western rosella bird. Partly because of this, doctors provisionally diagnosed hypersensitivity pneumonitis, an immune reaction to inhaled substances, and started steroids. Her blood tests for bird antibodies were negative. Two months later her breathing was worse and her blood oxygen was low. She did not improve with high-dose intravenous steroids and was put on a breathing machine in intensive care. A biopsy then showed mucinous adenocarcinoma that started in the lung, and a staging scan showed cancer in separate lobes of both lungs. She died two weeks after admission. The authors concluded that doctors should suspect cancer in atypical presentations, even in nonsmokers, and that the case supports early tissue diagnosis.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: Case report (one patient)
• Who was studied: One 84-year-old Caucasian woman, a lifelong nonsmoker, seen at a district general hospital; the authors are based at hospitals in London and Southend-on-Sea, England. Dates of care are not given.
• Exposure: No known asbestos exposure. She denied exposure to mold or damp, was a lifelong nonsmoker, and regularly looked after a Western rosella bird owned by her daughter.
• Main results:
  • The first chest X-ray showed extensive nodules in both lungs, involving all zones, with some reticulations toward the lower zones.
  • The chest CT showed numerous centrilobular nodules throughout both lungs, mainly in the lower lobes. A provisional diagnosis of hypersensitivity pneumonitis was made.
  • She was started on prednisolone. Her test for avian precipitins (bird antibodies) was negative.
  • Two months later she had worsening breathlessness and type 1 respiratory failure. She deteriorated despite intravenous methylprednisolone 500 mg and needed intubation and mechanical ventilation in intensive care.
  • A bronchoscopic biopsy showed mucinous adenocarcinoma with lepidic and papillary growth patterns, of primary lung origin.
  • A later staging scan (CT of the thorax, abdomen and pelvis) confirmed T4N0M1a disease, with cancer involving separate lobes in both lungs.
  • The patient died two weeks after admission despite intensive care.
• The authors' conclusion: The authors concluded that the case reinforces keeping a high index of suspicion for cancer in atypical presentations, even in nonsmokers. They added that it supports early tissue diagnosis to improve diagnostic accuracy.

Topics

Medical terms in this study, explained in our Lexicon: Pneumonitis, Lung Adenocarcinoma, Adenocarcinoma, Lung Cancer, Non-Small Cell Lung Cancer, Bilateral, Chest X-Ray, Pulmonary Fibrosis.

Related studies

• High-resolution computed tomography features of asbestosis versus fibrotic hypersensitivity pneumonitis: an observational study — R. Ma, S. Li, et al. (2022)
• Concomitant diagnosis of hypersensitivity pneumonitis and localized epithelioid mesothelioma: a rare case report — S.L. Martini, T.K.B.D. Silva, et al. (2025)
• Primary Malignant Pericardial Mesothelioma: A Clinical Case Series Illustrating the Necessity of a Multidisciplinary Approach — A.N. Rosenbaum, M.C. Bois, et al. (2019)
• The diagnostic utility of D2-40, calretinin, CK5/6, desmin and MOC-31 in the differentiation of mesothelioma from adenocarcinoma in pleural effusion cytology — T.S. Hyun, M. Barnes, et al. (2012)
• Diagnostic value of monoclonal antibody B72.3 in detecting adenocarcinoma cells in serous effusions — A.F. Lauritzen (1989)
• Diagnostic accuracy of Ber-EP4 for metastatic adenocarcinoma in serous effusions: a meta-analysis — B. Wang, D. Li, et al. (2014)

Browse more research in Curēus, or return to medical research.