Lung abscess as an adverse effect of Risankizumab.

BACKGROUND: Risankizumab is used for prolongated duration by patients, necessitating further research to characterize the infectious risks involved.

CASE PRESENTATION: A 30-year-old man on Risankizumab for psoriasis and alopecia presented with pleuritic chest pain, cough, hemoptysis, fever, and myalgias. Initial computed tomography (CT) scan showed a 4.9 × 7.7 × 6.1 cm irregular cavitary lesion in the medial right lower lobe with thickened walls and surrounding ground-glass opacification. Tuberculosis was ruled out with 3 negative acid-fast bacilli (AFB) samples and 2 negative samples forand rifampin resistance assay (Xpert MTB/RIF). Empiric antibiotic therapy was initiated, though the patient remained persistently febrile and tachycardic despite reported symptomatic improvement. A repeat CT scan showed compression atelectasis of the right middle and lower lobes, and a large right pleural effusion with multiple air-fluid levels. The patient underwent a video-assisted thoracoscopic surgery (VATS) decortication. Pleural fluid culture grew methicillin-resistant, and sputum AFB culture from admission grewthree weeks after collection. The patient ultimately completed two weeks of oral doxycycline.

CONCLUSION: Given the lack of notable risk factors for lung abscess, this case suggests a possible association with Risankizumab, which may have contributed to immunosuppression.