Ensemble Deep Learning Derived from Transfer Learning for Classification of COVID-19 Patients on Hybrid Deep-Learning-Based Lung Segmentation: A Data Augmentation and Balancing Framework

BACKGROUND AND MOTIVATION

Lung computed tomography (CT) techniques are high-resolution and are well adopted in the intensive care unit (ICU) for COVID-19 disease control classification. Most artificial intelligence (AI) systems do not undergo generalization and are typically overfitted. Such trained AI systems are not practical for clinical settings and therefore do not give accurate results when executed on unseen data sets. We hypothesize that ensemble deep learning (EDL) is superior to deep transfer learning (TL) in both non-augmented and augmented frameworks.

METHODOLOGY

The system consists of a cascade of quality control, ResNet-UNet-based hybrid deep learning for lung segmentation, and seven models using TL-based classification followed by five types of EDL's. To prove our hypothesis, five different kinds of data combinations (DC) were designed using a combination of two multicenter cohorts-Croatia (80 COVID) and Italy (72 COVID and 30 controls)-leading to 12,000 CT slices. As part of generalization, the system was tested on unseen data and statistically tested for reliability/stability.

RESULTS

Using the K5 (80:20) cross-validation protocol on the balanced and augmented dataset, the five DC datasets improved TL mean accuracy by 3.32%, 6.56%, 12.96%, 47.1%, and 2.78%, respectively. The five EDL systems showed improvements in accuracy of 2.12%, 5.78%, 6.72%, 32.05%, and 2.40%, thus validating our hypothesis. All statistical tests proved positive for reliability and stability.

CONCLUSION

EDL showed superior performance to TL systems for both (a) unbalanced and unaugmented and (b) balanced and augmented datasets for both (i) seen and (ii) unseen paradigms, validating both our hypotheses.

Study of Incidence, Clinical profile and Outcomes among patients hospitalized for COVID-19 with Acute Kidney Injury

The ongoing COVID-19 pandemic has thrown newer challenges for the health care professionals to manage the affected patients. Though the so called second wave is in a declining trend at present but possible third wave is looming in the near future. Initially patients appeared to have a respiratory limited disease but there are now increasing reports of multiple organ involvement including renal disease in association with COVID-19. The current study aims to highlight the incidence of acute kidney injury (AKI) in COVID-19 patients, as well as the clinical profile and outcomes in that subset of patients in a tertiary hospital setting, in order to better understand the role renal disease plays in the disease process.

MATERIAL

Methods: This retrospective, observational study involved a review of data from electronic health records of patients aged more than 18 years with laboratory confirmed COVID-19 admitted to our hospital from February 27 to May 30, 2021. Data was analysed using SPSS version-21.0 by descriptive statistics. We describe the incidence of AKI, dialysis requirement, requirement of mechanical ventilation and mortality.

OBSERVATION

Results of 400 hospitalized patients with COVID-19, 252(63%) were male, 148(37%) were female. AKI occurred in 72 (18%) patients. The proportions with stages 1, 2, or 3 AKI were 35(48.3%), 11 (15.1%), and 26 (36.6%), respectively. 22 (32%) patients with AKI required dialysis. About 42(58.33%) patients with AKI were admitted in Intensive care Unit and 35(48%) patients with AKI required mechanical ventilation. In-hospital mortality was (25%) among patients with AKI versus (7.01%) among those without AKI (OR, 4.42; 95% confidence interval, 2.23 to 8.73).

CONCLUSION

Conclusions AKI is common among patients hospitalized with COVID-19 and is associated with high morbidity and mortality.

In vivo effect of coronary laser angioplasty on atherosclerotic plaques: histopathologic analysis

Information from histopathologic examination of coronary arterial atherosclerotic plaques treated with in vivo laser energy is sparse. Directional atherectomy provides biopsies for study of tissue changes (injury) due to coronary arterial debulking devices, including laser. Sixteen patients who presented with acute ischemic coronary syndromes underwent debulking of a total of 17 obstructive intracoronary lesions with pulsed-wave holmium:YAG laser (2.1 microm wavelength). Laser was performed with the "pulse and retreat" technique which incorporates slow catheter advancement (0.5-1 mm/s) with controlled emission of energy. Immediately postlasing, directional atherectomy was utilized to obtain irradiated plaque tissue for pathologic examination. Extent of laser-induced tissue injury to plaques was graded as 0 (no tissue damage), 1 (small foci or charring and vacuoles), 2 (large amount of charring, edge disruption and vacuoles) and 3 (extensive tissue damage). Angiographically and clinically, all 17 lesions were successfully debulked with the laser energy (mean 47+/-25 pulses), with a reduction of target lesion percent diameter stenosis from 92+/-6% to 47+/-25%. Adjunct balloon dilations further reduced the target lesions to a final of 10+/-10% stenosis. The histopathologic examination of the lased specimens demonstrated that 13 lesions (76%) had no evidence of laser-induced injury (Grade 0). Four lesions had low-level injury (Grade 1), and none had evidence of Grade 2 or 3 laser-induced trauma. Therefore, a laser debulking technique, which incorporates slow catheter advancement with controlled emission of pulses, does not cause significant injurious effects to the irradiated plaque.

Multiple cutaneous malignancies in xeroderma pigmentosum

A case of xeroderma pigmentosum with multiple cutaneous malignancies is being reported. The case presented with freckles, letigens, and keratosis, a non-tender ulcerated nodular lesion on the nose, a nodular ulcerated lesion on the right outer canthus of the conjunctiva, and a nodular growth which developed on the right cheek which on histopathology was found to be squamous cell carcinoma, basal cell carcinoma and malignant melanoma respectively.

Telepathology between Richmond and Beckley Veterans Affairs Hospitals: report on the first 1000 cases

OBJECTIVE

A telepathology connection between Richmond VAMC and Beckley VAMC using dynamic robotic telepathology to provide pathology services remotely was established.

MATERIALS AND METHODS

This study reports a 14-month experience using telepathology to diagnose surgical specimens obtained from patients at the Beckley VA Medical Center and viewed in Richmond 250 miles away. Over 14 months, 2325 slides representing 1000 cases were viewed.

RESULTS

Discrepancies were observed in 20 of 2325 slides, or 0.86% of the total. None of the patients, where a discrepancy was found, were adversely affected by the preliminary report given.

CONCLUSIONS

This study demonstrates that telepathology is a reliable and cost-effective alternative to on-site pathology services and reviews advantages and disadvantages of the system.

Biotoxicity of mercury to Chlorella vulgaris as influenced by amino acids

The toxicity of mercury ion, on Chlorella vulgaris, is largely influenced by amino acids. Five amino acids, namely alanine, asparagine, glutamic acid, cysteine and histidine, were added separately to the medium containing static dose of mercury. Survival (%) of the alga was reduced with the increasing concentrations of mercury. Of these five amino acids, cysteine was found to be the most effective while alanine and glutamic acid were the least effective on reducing the toxic effect of mercury on the alga measured in terms of growth, chlorophyll and protein content. The order of detoxification was Alanine < Glutamate < Asparargine < Histidine < Cysteine. Amino acids from ligands with Hg2+ making it less toxic to the alga and produce an additional source of energy for growth and development.

Storage pool disease in chronic lymphocytic leukemia: abnormal aggregation and secretion without bleeding

Although bleeding complications are relatively common in patients with chronic lymphocytic leukemia, they tend to be related to thrombocytopenia or an acquired clotting factor inhibitor. Chronic lymphocytic leukemia-associated thrombocytopenia, which may also contribute to the hemorrhagic risk, is generally caused by decreased production and immune-mediated destruction. This is the case of a 56-year-old man with longstanding chronic lymphocytic leukemia who developed thrombocytopenia (platelet counts of approximately 50,000/microL) with an associated abnormal platelet morphology. Although the patient did not suffer clinically significant bleeding, several tests of platelet function were grossly abnormal. Electron microscopic examination of the platelets revealed virtually complete absence of dense granules. Platelet aggregation did not occur with adenosine diphosphate (10 microM), collagen (2 micrograms/mL), or ristocetin (1 mg/mL). Doubling the agonist concentrations produced only minimal agglutination with ristocetin. The bleeding time was mildly prolonged at 9.0 and 10.5 minutes. Von Willebrand antigen and ristocetin cofactor levels were normal. Collagen-induced adenosine triphosphate secretion was less than 10% that of a matched normal control. In contrast, platelet force development was virtually normal, reaching 4,800 dynes at 1,200 seconds compared with 5,800 dynes for the healthy control. The patient's clots demonstrated enhanced clot modulus 44,000 dynes/cm2 versus 22,400 dynes/cm2 for the healthy control. The latter finding was primarily because of high fibrinogen concentration. This third report of storage pool disease in a patient with chronic lymphocytic leukemia demonstrates that dense granule release is not required for normal platelet-mediated force development.

Fine needle aspiration cytology (FNAC) in malignant bone tumours

Patients with malignant bone tumours often come at a very late stage of disease to Medical Colleges. Because of their high mortality rate, accurate & quick diagnosis of these lesions become essential, inspite of clinical, radiological and histopathological assessments. A simple, inexpensive, safe & least traumatic technique-fine needle aspiration cytology (FNAC) in diagnosis of 55 malignant bone tumours was carried out. Specific tumour types metastatic tumour (12), Giant cell tumour (12), Ewing's sarcoma (10), Osteosarcoma (7), Multiple myeloma (7), Chordoma (3), Chondrosarcoma (3) and Fibrosarcoma (1) could be ascertained in 87.2% whereas malignant tumour was suggested in 94.5% (52 cases).