PneumocystisPneumonia Presenting as an Enlarging Solitary Pulmonary Nodule

Abstract

Pneumocystis pneumonia is a life threatening infection that usually presents with diffuse bilateral ground-glass infiltrates in immunocompromised patients. We report a case of a single nodular granulomatous Pneumocystis pneumonia in a male with diffuse large B-cell lymphoma after R-CHOP therapy. He presented with symptoms of productive cough, dyspnea, and right-sided pleuritic chest pain that failed to resolve despite treatment with multiple antibiotics. Chest X-ray revealed right lower lobe atelectasis and CT of chest showed development of 2 cm nodular opacity with ground-glass opacities. Patient underwent bronchoscopy and biopsy that revealed granulomatous inflammation in a background of organizing pneumonia pattern with negative cultures. Respiratory symptoms resolved but the solitary nodular opacity increased in size prompting a surgical wedge resection which revealed granulomatous Pneumocystis pneumonia infection. This case is the third documented report of Pneumocystis pneumonia infection within a solitary pulmonary nodule in an individual with hematologic neoplasm. Although Pneumocystis pneumonia most commonly occurs in patients with HIV/acquired immunodeficiency syndrome and with diffuse infiltrates, the diagnosis should not be overlooked when only a solitary nodule is present.

Granulomatous Pneumocystis jirovecii mimics pulmonary metastasis in rectal cancer

“…[1][2][3] It rarely presents as a single lung nodule in chest CT. To date, there were only four published case reports of single solitary lung nodule of GPJP, including three cases with diffuse large B-cell lymphoma, and one immunocompetent patient. 3,4 Indeed, our case is the first report of single PJP granuloma, associated with rectal cancer and previous pulmonary Tb.Bronchoalveolar lavage can diagnose PJP, but has low diagnostic yield to detect GPJP. 1,5 Surgical resection can diagnose GPJP and remove lesions.…”

“…1,5 Surgical resection can diagnose GPJP and remove lesions. [1][2][3][4] Fungi granulomas can be reliably distinguished by pathologic characteristics in GMS stain. The histopathologic feature of PJP appears as thin-walled, spherical, 2 to 5 μm, larger intracystic bodies, and lacks budding forms, as presented.…”

“…Bronchial brushings, needle aspiration, and transbronchial and image-guided biopsy are not favorable. 4 So surgical lung biopsy appears to be safe and accurate, especially in immunocompromised patients, and becomes a superior diagnostic tool. 3 Our patient was relatively immunocompetent and has neither airway symptoms nor infection signs, so the first impression of such a new spiculated solitary lung nodule might be pulmonary metastasis, and the second should be primary lung cancer.…”

Multiple Mass Lesions in Pneumocystis Pneumonia

“…We encountered a rare case of PCP in an HIV-negative patient with multiple lung mass lesions. A typical chest CT image of PCP shows bilateral GGO [ 1 - 3 ], and even if nodules or mass lesions are observed, they are often surrounded by GGO [ 6 - 8 ]. Nodules or mass lesions have been reported to reflect granulomas [ 6 ], and our patient was considered to have some degree of sustained immune function against infection.…”

Fine‐needle aspiration of granulomatous pneumocystosis

“…A literature review yielded a paucity of case reports where granulomatous pneumocystosis presented as a solitary or multiple lung masses diagnosed by lung wedge resection. [4][5][6] To the best of our knowledge, the cytopathologic findings in fine-needle aspiration (FNA) of lung nodules caused by granulomatous pneumocystosis have not been described.…”