ABSTRACT
SESSION TITLE: Infectious Complications with Obstructions and Connections SESSION TYPE: Case Reports PRESENTED ON: 10/17/2022 03:15 pm - 04:15 pm INTRODUCTION: Invasive pulmonary fungal infections are a challenge for diagnosis. One of the most common types is Invasive pulmonary aspergillosis. It occurs usually among immunocompromised patients [1], so an early diagnosis is warranted for potential better outcome. Evidence of calcium oxalate can be an early diagnostic tool for such an infection. The presence of calcium oxalate crystals can be detected within 24 hours under polarized light in the microbiology labs. We present this case to highlight the potential importance of pulmonary oxalosis in diagnosing pulmonary aspergillosis. CASE PRESENTATION: A 62-year-old-woman with limited breast cancer was admitted to the hospital seven days after her last cycle of docetaxel and cyclophosphamide with COVID-19 pneumonia and hypoxemic respiratory failure. She was not neutropenic. She received a full course of dexamethasone and remdesivir. Sputum cultures subsequently grew Klebsiella aerogenes for which she was treated with antibiotics but failed to significantly improve over four weeks. Repeat chest computed tomography (CT) showed progressive multifocal airspace opacities with new areas of cavitation. Patient underwent bronchoscopy with bronchoalveolar lavage (BAL) and transbronchial biopsy. Transbronchial biopsy specimen from the right upper lobe showed bronchial mucosa and lung parenchyma with calcium oxalate crystals and no organisms. Biopsy specimen from the right middle lobe showed fungal organisms consistent with Aspergillus invading bronchial mucosa and lung parenchyma. Several days later, serum beta-D-glucan returned within normal limits, serum galactomannan was significantly elevated, and BAL culture grew Aspergillus niger. Patient improved with antifungal therapy. DISCUSSION: Fungal pneumonia has high morbidity and mortality. It is essential to start antifungal therapy as soon as possible. Pulmonary oxalosis or calcium oxalate has been seen among Aspergillus Fumigatus and Aspergillus Niger [2-3]. It is a combination of oxalic acid which is produced by Aspergillus spp. and calcium from blood supply of an invaded tissue. Further progression of lesions can be due to calcium oxalate toxicity itself [4-5]. In our case, clinical suspicion for pulmonary aspergillosis was high and we were able to document fungal invasion of lung parenchyma on one of the lung specimens. Though fungal culture is very sensitive and specific, it can take several days to result. Tissue staining for crystals can be performed quickly and provide more timely information when deciding about starting anti-fungal therapy. CONCLUSIONS: Pulmonary oxalosis, calcium oxalate deposition, can be seen in aspergillus infection and should be considered as an early diagnostic tool for invasive pulmonary aspergillosis. Reference #1: Kousha M, Tadi R, Soubani AO. Pulmonary aspergillosis: a clinical review. Eur Respir Rev. 2011;20(121): 156–174, doi: 10.1183/09059180.00001011 Reference #2: U. Pabuccuoglu, Aspects of oxalosis associated with aspergillosis in pathology specimens, Pathol. Res. Pract. 201 (2005) 363–368 Reference #3: Osholowu OS, Kak V, Singh H. Pulmonary oxalosis in pulmonary aspergillosis syndrome. Adv Respir Med. 2020;88(2):153-156. doi: 10.5603/ARM.2020.0090. PMID: 32383468. DISCLOSURES: No relevant relationships by Mohammed Alsaggaf No relevant relationships by Daniel Baram No relevant relationships by Ivana Milojevic
ABSTRACT
In this article, a graphene-based multilayered surface plasmon resonance (SPR) biosensor of (BK7/WS2/Au/BaTiO3/Graphene) is proposed for the rapid detection of the novel coronavirus (COVID-19). The proposed SPR biosensor is designed based on the angular interrogation attenuated total reflection (ATR) method for rapid detection of the COVID-19 virus. The sensor's surface plasmon polaritons (SPPs) and the sensing region refractive index (RI) are changed, owing to the interaction of various concentrated ligand-analytes. The specific ligand is mechanized with the proposed sensor surface and the target analyte that has flowed onto the sensing surface. The proposed sensor is capable of detecting the COVID-19 virus rapidly in two different ligand-analytes environments, such as: (i) the virus spike receptor-binding domain (RBD) as an analyte and monoclonal antibodies (mAbs) as a probe ligand, and (ii) the monoclonal antibodies (IgG or IgM) as an analyte and the virus spike RBD as a probe ligand. Due to the binding of the target ligand-analytes, the concentration level of the sensing region is incremented. As the increment in the concentration level, the RI of the sensing medium increases, therefore the change in RI causes the shift in the SPR angle resulting in the output reflectance intensity. The performance of the multilayered SPR sensor is analyzed numerically using the finite element method (FEM) method. Numerically, the proposed sensor provides the maximum angular shift sensitivity at 230.77 deg/refractive index unit (RIU), detection accuracy (DA) at 0.161 deg(-1), and the figure of merits (FOM) is at 37.22 RIU-1. In addition, with each additional graphene layer number (L), the proposed sensor exhibits the angular shift sensitivity increment (1 + 0.7L) times. The novelty of the proposed multilayer (BK7/WS2/Au/BaTiO3/Graphene) sensor is highly angular sensitivity, and capable of detecting the COVID-19 virus rapidly without a false-positive report. (C) 2022 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement