Pleural fluid secondary to pulmonary cryptococcal infection: a case report and review of the literature

Abstract

Background Pulmonary Cryptococcosis (PC) is diagnosed with increasing incidence in recent years, but it does not commonly involve the pleural space. Here, we report a HIV-negative case with advanced stage IIIB non-small cell lung cancer (NSCLC) treated with radiation therapy presented with dyspnea, a new PET-positive lung mass and bilateral pleural effusion suspecting progressive cancer. However, the patient has been diagnosed as pulmonary cryptococcal infection and successfully treated with oral fluconazole therapy. Case presentation A 77-year-old male with advanced stage non-small cell lung cancer treated with combined chemo-radiation therapy who presented with progressive dyspnea, a new PET-positive left lower lobe lung mass and bilateral pleural effusions. Initial diagnostic thoracentesis and bronchoscopy yielded no cancer, but instead found yeast forms consistent with cryptococcal organisms in the transbronchial biopsies of the left lower lobe lung mass. Subsequent to this, the previously collected pleural fluid culture showed growth of Cryptococcus neoformans . The same sample of pleural effusion was tested and was found to be positive for crytococcal antigen (CrAg) by a lateral flow assay (LFA). The patient has been treated with oral fluconazole therapy resulting in gradual resolution of the nodular infiltrates. Conclusion PC should be considered in immunosuppressed cancer patients. Additionally, concomitant pleural involvement in pulmonary cryptococcal infections may occur. The incidence of false positive 18 FDG-PET scans in granulomatous infections and the use of CrAg testing in pleural fluid to aid in diagnosis are reviewed.

Metabolic Adaptations in Cancer Stem Cells

“…Thus, glutamine has an important role in metabolic rewiring in OxPhos impaired cells to provide energy and other synthetics intermediates ( 233 ). Many researchers are attempting to target the glutamine-dependent self-renewal ability of CSCs as a novel therapeutic approach ( 234 – 236 ). For example, attempts to inhibit glutamine transamination in glioblastoma, blocking the increased glutamine regulated signaling pathways (mTOR pathway), or by targeting c-myc regulated glutamine uptake were shown to induce significant cytotoxicity to tumor cells ( 237 , 238 ).…”

Pleural involvement in cryptococcal infection

“…The majority of pulmonary nodules were observed in the lower lobes and in a subpleural distribution. Of note, 26 patients had only pleural effusion on computed tomography imaging[ 11 , 12 ].…”

“…Pleural fluid cultures for Cryptococcus neoformans are frequently negative, most likely due to the small number of fungi present[ 11 ]. CrAg test is considered an effective non-invasive diagnostic tool, with its role in serum and cerebrospinal fluid being well accepted with high sensitivity and specificity[ 12 ]. Additionally, this test has a low incidence of false-positive reactions, making it valuable in diagnosing cryptococcosis when cultures of pleural fluid are negative[ 11 ].…”

Bilateral pleural effusion: etiology, diagnostics

“…ДПВ может осложнять течение грибковых пневмоний, которые обычно развиваются у лиц с иммунодефицитами различной этиологии. Так, описаны случаи двустороннего плеврита при паракокцидиоидомикозе [26], криптококкозе [27], при этом в материале, полученном при биопсии легкого, и ПЖ обнаружен рост Cryptococcus neoformans. ДПВ может наблюдаться при паразитарных поражениях легких и плевры.…”