Pictorial Review of Post COVID-19 Acute Invasive Fungal Sinusitis: Clinical Radiologists' Perspective.

Acute invasive fungal sinusitis (AIFS) is a rapidly progressive infection predominantly seen in immunocompromised patients. There is an increasing incidence of AIFS post COVID-19 infection. Yet, there is sparse literature regarding spectrum of cross-sectional imaging findings (CT and MRI) in these patients, which is prudent for appropriate timely surgical intervention. This study aims to highlight spectrum of imaging findings in patients with post-COVID-19 AIFS integrating the clinical details from presentation to follow-up. We retrospectively reviewed the demographics, clinical details and radiological imaging of 31 histopathological proven cases of post COVID-19 AIFS. MR and CT images of these patients were retrieved from the PACS and analysed. 90-day follow-up of these patients was obtained. Statistical analysis was performed using descriptive statistics. Cross-sectional imaging showed nasal cavity involvement in all patients, bilateral in (15, 48%) cases; predominant involvement of maxillary (31, 100%) followed by ethmoid sinuses (29, 93.5%) was seen. MR showed patchy/complete loss of normal mucosal enhancement in the turbinates and sinuses as predominant imaging finding. Maxillary sinus walls erosions were seen in 28 cases (90%). Rhino-orbital and rhino-orbito-cerebral mycosis was seen in 24 (77%) and 14 (45%) respectively. Optic nerve-sheath complex was involved in 15 (48%) cases. Cerebral involvement was seen in form of meningeal enhancement, cerebritis, ischemic changes, cavernous sinus and intracranial arterial thrombosis and aneurysms. Comprehensive knowledge of imaging features of AIFS and recognition of extent of their spread allows radiologists to play pivotal role in alerting the clinician for appropriate therapy to avoid protracted and fatal outcome.

Establishment and Characterization of Brain Cancer Primary Cell Cultures From Patients to Enable Phenotypic Screening for New Drugs.

Aim: Desmoplastic infantile ganglioglioma (DIG), is a rare tumor arising mainly during the first 2 years of life. Molecular characterization of these benign yet rapidly proliferating tumors has been limited to evaluating a few mutations in few genes. Our aim was to establish a live cell culture to enable the understanding of the cellular processes driving the non-malignant growth of these tumors. Methods: Tumor tissue from a rare non-infantile 8-year-old female DIG patient was dissociated and digested using collagenase to establish live cultures. Both 2D monolayer and 3D neurospheres were successfully cultured and characterized for proliferative potential, intrinsic plasticity, presence of cancer stem cells and the expression of stem cell markers. Cells cultured as 3D were embedded as tissue blocks. Immunohistochemistry was performed in both tissue and 3D sections for markers including synaptophysin, vimentin, neurofilament and MIB-1. Mutation analysis by NGS was performed using a-100 gene panel. Results: Using immunohistochemistry, the 3D cultures were shown to express markers as in the original DIG tumor tissue indicating that the spheroid cultures were able to maintain the heterogeneity found in the original tumor. Cells continued proliferating past passage 10 indicative of immortalization. Enrichment of cancer stem cells was observed in neurospheres by FACS using CD133 antibody and RT-PCR. Mutation analysis indicated the presence of germline mutations in three genes and somatic mutations in two other genes. Conclusion: A spontaneous cell line-like cell culture with high percentage of stem cells has been established from a DIG tumor for the first time.

Pituitary carcinoid coexisting with systemic lupus erythematosus: A rare combination.

Gastrointestinal carcinoids have occasionally been reported in patients with autoimmune diseases. We report a middle-aged woman who presented with episodic hypertension and a skin rash. Initial evaluation led to the diagnosis of systemic lupus erythematosus for which the patient was treated. Further investigations revealed the presence of a carcinoid tumour in the pituitary. Although gastrointestinal carcinoids associated with autoimmune diseases have been seen occasionally, to our knowledge, extragastric carcinoid coexisting with an auto- immune disorder has never been reported before. A better understanding of how inflammation induces cytological changes leading to development of a carcinoid from a cellular and molecular perspective could provide potential therapeutic strategies for preventing these lesions.