Pulmonary Cryptococcus Presenting as a Solitary Pulmonary Nodule

Cryptococcosis Associated With Biologic Therapy: A Narrative Review

Cryptococcus is an opportunistic fungal pathogen that can cause disseminated infection with predominant central nervous system involvement in patients with compromised immunity. Biologics are increasingly used in the treatment of neoplasms and autoimmune/inflammatory conditions and the prevention of transplant rejection, which may affect human defense mechanisms against cryptococcosis. In this review, we comprehensively investigate the association between cryptococcosis and various biologics, highlighting their risks of infection, clinical manifestations, and clinical outcomes. Clinicians should remain vigilant for the risk of cryptococcosis in patients receiving biologics that affect the Th1/macrophage activation pathways, such as tumor necrosis factor α antagonists, Bruton tyrosine kinase inhibitors, fingolimod, JAK/STAT inhibitors (Janus kinase/signal transducer and activator of transcription), and monoclonal antibody against CD52. Other risk factors-such as age, underlying condition, and concurrent immunosuppressants, especially corticosteroids-should also be taken into account during risk stratification.

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

Objective

To 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 Methods

A 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.

Results

We 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.

Conclusions

The 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.

Ibrutinib, a Bruton's tyrosine kinase inhibitor, a new risk factor for cryptococcosis

PURPOSE

Invasive fungal diseases and especially Cryptococcus neoformans infections are increasingly reported in patients with hematological malignancies receiving ibrutinib, a Bruton's tyrosine kinase inhibitor.

PATIENTS AND METHOD

We reported three additional cases and reviewed 16 previous published cases together with cases from the international pharmacovigilance database.

RESULTS

Patients were mainly treated for chronic lymphocytic leukemia. Cryptococcosis mostly occurred during the first six months (66%) and especially the first two months (44%) of treatment. Clinical presentation is often pulmonary (68%) and the outcome is usually favorable despite ibrutinib continuation.

CONCLUSION

Clinicians must be aware of this infection in patients with hematological malignancies on ibrutinib.

Clinical features of pulmonary cryptococcosis in thin-section CT in immunocompetent and non-AIDS immunocompromised patients

RATIONAL AND OBJECTIVES

To compare thin-section computed tomography (CT) features of pulmonary cryptococcosis (PC) in immunocompetent and non-AIDS immunocompromised patients.

MATERIALS AND METHODS

We retrospectively reviewed CT findings of 18 immunocompetent and 24 non-AIDS immunocompromised patients with clinically proven PC. Different patterns of pulmonary abnormalities between the two groups of patients were compared by Fisher's exact test.

RESULTS

Pulmonary nodules were present in 37 of the 42 patients. Masses were detected in 16 patients and consolidation in 9. There were 12 patients with a solitary nodule or mass. Masses were associated with nodules in 12 patients. Consolidation was associated with nodules/masses in nine patients. The nodules/masses were associated with cavitations in 13 patients. Margination of nodules/masses was well defined in nine patients and ill-defined in 33. The abnormalities were predominantly distributed in the peripheral region of the lung (n = 29, 69.0%). The presence of cavitations in nodules/masses was significantly more frequent in non-AIDS immunocompromised than in immunocompetent patients (P = 0.001).

CONCLUSIONS

The most common thin-section CT feature of PC was pulmonary nodules/masses, which were ill-defined and located peripherally. Cavitations within nodules/masses were more commonly found in non-AIDS immunocompromised patients. PC should be considered in the differential diagnosis of pulmonary nodules/masses.

Invasive aspergillosis complicating treatment with tyrosine kinase inhibitors

We describe three cases of pulmonary aspergillosis (PA) in three patients without traditional risk factors for invasive aspergillosis infection, such as prolonged neutropenia or high dose systemic corticosteroid therapy. All three patients developed PA while taking tyrosine kinase inhibitors (TKI) and sustained greater clinical improvement once TKI were withdrawn. Our case series supports the theory TKI treatment can increase susceptibility to PA without causing neutropenia. Recognition that TKI treatment may predispose to invasive aspergillosis will allow for rapid recognition of affected patients and more effective management of future cases.