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"Medical Journeys" is a set of clinical resources reviewed by physicians, meant for the medical team as well as the patients they serve. Each episode of this journey through a disease state contains both a physician guide and a downloadable/printable patient resource. "Medical Journeys" chart a path each step of the way for physicians and patients and provide continual resources and support, as the caregiver team navigates the course of a disease.

This month: A noteworthy case study.

What caused a 70-year-old man with ulcerative colitis to suddenly develop shortness of breath, fatigue, and debilitating weakness? That's what Javier Leonardo Galindo Pedraza, of Hospital Universitario Mayor in Bogotá, Colombia, and colleagues needed to determine. As the team reported in an abstract presented at the American Thoracic Society's 2023 International Conference, the patient told clinicians that the symptoms had developed about a week earlier.

His medical history revealed that he was a former smoker of five pack-years for 20 years and had developed ulcerative colitis about 2 years previously. He had been receiving treatment with mesalazine, and for the past month azathioprine had been added. He had no other notable exposures.

Chest x-ray showed basal parenchymal opacities. To manage the respiratory failure, the patient received 4 days of invasive mechanical ventilation, and given the possibility of a bacterial infection, the team also prescribed antibiotics.

High-resolution computed tomography (HRCT) of the chest found "multilobar ground-glass opacities, traction bronchiectasis, and subtle honeycombing with basal and peripheral predominance," the case authors noted.

The findings revealed a fibrotic nonspecific interstitial pneumonia . HRCT taken 2 years previously had shown subtle basal and peripheral reticulation.

Surgical lung found evidence of "pulmonary architectural distortion, honeycombing, mild chronic inflammation, and some intraluminal fibrous polyps within air spaces," Galindo Pedraza and co-authors said. Blood tests showed that the patient had a positive antinuclear antibody titer of 1:160 with a nuclear dense fine speckled pattern (AC-2); he tested negative for extractable nuclear antigen antibodies and rheumatoid factor.

Given that his symptoms and imaging findings suggested pulmonary progressive fibrosis concomitant with organizing pneumonia, the team suspected mesalazine-induced cardiotoxicity. They discontinued treatment with mesalazine and started the patient on a monthly regimen of cyclophosphamide, which resulted in an improvement in his symptoms.

Discussion

Although extraintestinal manifestations of inflammatory bowel disease (IBD) are frequent, pulmonary manifestations are rare. Thus, this case of fibrosing chronic interstitial lung disease (ILD) in an ulcerative colitis patient is "highly unusual," Galindo Pedraza and co-authors noted.

Among patients with IBD who develop ILD, almost half (45.4%) present with organizing pneumonia years after being diagnosed with IBD (median 10.3 years), and the lung disease is considered to be unrelated to bowel disease activity, the team explained.

Patients with IBD are more likely to develop secondary bronchial disorders, such as obstructive pulmonary disease or bronchiectasis, than interstitial lung disease, the case authors continued.

ILD can be triggered by both IBD and some of the medications used to treat it, including aminosalicylates (mesalazine and sulfasalazine), azathioprine, and anti-tumor necrosis factor-α.

The team explained that when mesalazine develops, it is a diagnosis of exclusion: "It may manifest as organizing pneumonia (22.2%), unclassified ILD (55.5%), or eosinophilic pneumonia (3.3%) -- rarely with fibrosing ILD." In this particular patient, the timing of his symptoms suggested that ulcerative colitis likely caused the lung disease to develop, as opposed to organizing pneumonia, which "would be caused by either IBD or mesalazine use," the authors stated.

Treatment with systemic steroids would be expected to improve symptoms of organizing pneumonia, pulmonary infiltrates with eosinophilia, and necrobiotic nodules, and when toxicity is suspected, drug withdrawal, Galindo Pedraza and co-authors explained.

They concluded that although targeted treatment for pulmonary fibrosis remains unknown, they suggest use of immunosuppressive agents such as cyclophosphamide, as was done for this patient.

Read previous installments in this series:

Part 1: UC: Understanding the Epidemiology and Pathophysiology

Part 2: UC: Symptoms, Exams, Diagnosis

Part 3: UC: How and Why Does It Arise?