Pulmonary cryptococcosis after immunomodulator treatment in patients with Crohn’s disease:Three case reports

BACKGROUND Corticosteroids and anti-tumor necrosis factorαmAbs are widely used to treat Crohn's disease(CD).However,one disadvantage of this treatment is impairment of normal immune function,leading to an increased risk of infection.Cryptococcus infection is an opportunistic infection that occurs mainly in immunocompromised patients and poses a significant diagnostic challenge in patients with CD.CASE SUMMARY Here,we report three cases of pulmonary cryptococcosis in patients with CD after receiving immunomodulatory treatment.The patients presented with no or mild respiratory symptoms.Chest computed tomography scans revealed pulmonary nodules in the unilateral or bilateral lobes.Diagnoses were made using pathological examination and metagenomic sequencing.The patients were treated with fluconazole 400 mg once daily for 1 to 6 mo,and symptoms were resolved.Literature searches were conducted in PubMed,Web of Science,and Embase to retrieve previously reported cases and summarize patient characteristics.CONCLUSION The incidence of cryptococcus infection has increased along with immunomodulator use.Clinical vigilance is required for early identification and standardized treatment.

Clinical characteristics of pulmonary cryptococcosis coexisting with lung adenocarcinoma:Three case reports

BACKGROUND Pulmonary cryptococcosis (PC) is an invasive fungal disease caused mainly byCryptococcus (C.) neoformans or C. gattii. It may be present in immunocompetent orimmunocompromised patients. The radiographic features of PC vary, and themost common computed tomography manifestation is the presence of solitary ormultiple pulmonary nodules or masses distributed in the outer zone of the lungfield. The appearance of nodular or mass-like PC on computed tomography scansresembles that of primary or metastatic lung cancers, and differential diagnosis issometimes difficult. The coexistence of PC and malignant tumors is rarelyobserved.CASE SUMMARY This paper reports three cases of PC combined with lung adenocarcinomadiagnosed by video-assisted thoracic surgery lung biopsy, which weresuccessfully managed by early diagnosis and treatment.CONCLUSION The present case report might serve as a reminder not to neglect PC coexistingwith adenocarcinoma. Early diagnosis and treatment lead to a better prognosis.

Cryptococcal antigen testing of lung tissue homogenate improves pulmonary cryptococcosis diagnosis:Two case reports

BACKGROUND Pulmonary cryptococcosis(PC)is an opportunistic infectious disease of the respiratory system.Lung tissue biopsies,culture of respiratory samples(e.g.,sputum,lung tissue,pleural fluid,and bronchoalveolar lavage fluid),and cryptococcal antigen(CrAg)testing are helpful for a definitive diagnosis.However,these tests are sometimes falsely negative.PC is often misdiagnosed or underdiagnosed owing to the absence of obvert symptoms,poor imaging specificity,and false-negative laboratory tests.CASE SUMMARY We report two female patients who underwent computed tomography-guided percutaneous needle pulmonary biopsy of a lung nodule for a confirmed diagnosis.In both patients,the CrAg test on the lung biopsy tissue homogenate was positive,while the serum CrAg test was negative.Combined with the lung tissue pathology,we made the diagnosis of PC.Antifungal therapy was effective in both patients.CONCLUSION Given the findings of our cases and the literature review,lung tissue homogenate CrAg testing can be helpful in improving the diagnosis of PC.

Extent of Lung Involvement and Serum Cryptococcal Antigen Test in Non-Human Immunodeficiency Virus Adult Patients with Pulmonary Cryptococcosis

Background： Serum cryptococcal antigen （CrAg） test is the most used noninvasive method to detect cryptococcal infection. However, false-negative CrAg test is not uncommon in clinical practice. Then, the aim of this study was to investigate the factors associated with false-negative CrAg test among non-human immunodeficiency virus （HIV） adult patients with pulmonary cryptococcosis and its clinical features. Methods： One hundred and fourteen non-HIV adult patients with pulmonary cryptococcosis, proven by biopsy, were retrospectively reviewed. Finally, 85 patients were enrolled; 56 were CrAg positive （CrAg＋ group） and 29 were negative （CrAg- group）. It was a cross-sectional study. Then, baseline characteristics, underlying diseases, clinical symptoms, laboratory findings, and chest radiological findings were reviewed and analyzed. Chi-square test was used to analyze categorical variable. Odds ratio （OR） was used to measure correlation. Student＇s t-test was obtained to analyze continuous variable. Results： No difference in baseline characteristics, underlying diseases, clinical symptoms, and laboratory findings were found between two groups （P 〉 0.05 in all）. Nevertheless, diffuse extent lesion was 82.1% in CrAg＋ group and 10.3% in CrAg- group （χ2 = 40.34, P〈 0.001; OR = 39.87）. Conclusions： Among patients with limited pulmonary involvement, a negative serum CrAg does not preclude the diagnosis of pulmonary cryptococcosis. However, among patients with extensive pulmonary involvement, serum CrAg is a useful diagnostic tool for pulmonary cryptococcosis. Furthermore, we also noticed that the untypical and mild presentations with extensive pulmonary lesion might be the features of pulmonary cryptococcosis, which needs further investigation.