Development and Validation of a Radiomics Nomogram for Differentiating Pulmonary Cryptococcosis and Lung Adenocarcinoma in Solitary Pulmonary Solid Nodule

ObjectiveTo establish a CT-based radiomics nomogram model for classifying pulmonary cryptococcosis (PC) and lung adenocarcinoma (LAC) in patients with a solitary pulmonary solid nodule (SPSN) and assess its differentiation ability.Materials and MethodsA total of 213 patients with PC and 213 cases of LAC (matched based on age and gender) were recruited into this retrospective research with their clinical characteristics and radiological features. High-dimensional radiomics features were acquired from each mask delineated by radiologists manually. We adopted the max-relevance and min-redundancy (mRMR) approach to filter the redundant features and retained the relevant features at first. Then, we used the least absolute shrinkage and operator (LASSO) algorithms as an analysis tool to calculate the coefficients of features and remove the low-weight features. After multivariable logistic regression analysis, a radiomics nomogram model was constructed with clinical characteristics, radiological signs, and radiomics score. We calculated the performance assessment parameters, such as sensitivity, specificity, accuracy, negative predictive value (NPV), and positive predictive value (PPV), in various models. The receiver operating characteristic (ROC) curve analysis and the decision curve analysis (DCA) were drawn to visualize the diagnostic ability and the clinical benefit.ResultsWe extracted 1,130 radiomics features from each CT image. The 24 most significant radiomics features in distinguishing PC and LAC were retained, and the radiomics signature was constructed through a three-step feature selection process. Three factors—maximum diameter, lobulation, and pleural retraction—were still statistically significant in multivariate analysis and incorporated into a combined model with radiomics signature to develop the predictive nomogram, which showed excellent classification ability. The area under curve (AUC) yielded 0.91 (sensitivity, 80%; specificity, 83%; accuracy, 82%; NPV, 80%; PPV, 83%) and 0.89 (sensitivity, 81%; specificity, 83%; accuracy, 82%; NPV, 81%; PPV, 82%) in training and test cohorts, respectively. The net reclassification indexes (NRIs) were greater than zero (p < 0.05). The Delong test showed a significant difference (p < 0.0001) between the AUCs from the clinical model and the nomogram.ConclusionsThe radiomics technology can preoperatively differentiate PC and lung adenocarcinoma. The nomogram-integrated CT findings and radiomics feature can provide more clinical benefits in solitary pulmonary solid nodule diagnosis.

A Retrospective Analysis of Pulmonary Cryptococcosis Following Kidney Transplantation: Clinical Presentation, Treatment and Effectiveness

Background: The use of immunosuppressors and a relatively weaken cell-mediated immunity make organ transplant recipients particularly vulnerable to cryptococcosis infection. Patients infected usually present only nonspecific symptoms, making it extremely possible for misdiagnosis and inappropriate choice of therapeutic approach. Methods: We compiled and analysed data of patients received kidney transplant in our hospital between April 2006 to January 2021. Results: 18 patients were enrolled into the study, ranging between 27-68 years old. The median time from kidney transplantation to pathologically-confirmed infection was 4.09 years. All patient’s respiratory system was affected, showing symptoms including sputum-producing cough and fever. 3 patients (16.67%) also developed central nervous system (CNS) infections. Nodule-shaped infectious sites were frequently observed (10, 58.82%) in chest CT. Blood works showed no specific changes. 7 patients received thoracoscopic lobectomy in suspicion of lung cancer. 3 patients first received antifungal therapy for a period of time and then underwent thoracoscopic lobectomy. No recurrence whatsoever was observed in all 10 surgically-intervened patients. 8 patients received only antifungal therapy, 7 of them showed a substantial reduction in the size of the infectious site. Fluconazole was most frequently prescribed for antifungal therapy. Conclusion: Most patients developed pulmonary cryptococcosis 2 years after transplantation. Patients usually demonstrate symptoms like fever and sputum-producing cough. The possibility of cryptococcal meningitis shouldn’t be ruled out if corresponding symptoms occur. CT presentation may be confused with lung cancer. Fluconazole is commonly prescribed for treatment and can usually yield satisfied outcome. In patients received unsatisfactory antifungal therapy, surgical therapy should be considered a possibility.