Phenotypes of post covid interstitial lung disease, clinical, radiological, and pathological correlations

Introduction: The clinical-radiologic-pathologic features of post-COVID interstitial lung disease (ILD) remain to be explored. Method(s): In a prospective multicenter Italian study (PCOILS), subsequent patients seen at 4-18 months after the acute infection underwent transbronchial lung cryobiopsy and BAL if they showed a significant ILD (progressive and/or symptomatic and/or with pulmonary function impairment). Result(s): 19 patients enrolled;characteristics are summarized in Fig.2. We identified 3 post-COVID phenotypes: 1) prominent vascular changes;2) post-COVID fibrosis;3) persistent COVID. Fig. 1. Phenotype 1 was detected only in 2 cases with similar characteristics as showed in Fig. 1 Phenotype 2 was detected in 7 patients all with HRCT NSIP/OP features. Histology showed fibrotic or mixed NSIP, fibrotic OP, fibrotic DAD and bronchiolar damage. Phenotype 3 was detected only in the case reported in Fig.1.The remaining 9 patients were reclassified as known ILDs and treated according to current guidelines. Conclusion(s): We identified 3 phenotypes of postcovid damage with heterogeneous pictures and leading to differenttreatment choices.

Role of BAL in COVID-19 patients: a prospective multicentre study

The present study is part of DRAGON, a prospective multicentre European project aimed at improving the diagnosis of COVID-19. The primary aim of this study is to evaluate BAL role in detecting coexisting infections. Secondary aims are BAL impact on the management of COVID patients, characteristics of BAL cellularity in COVID patients, and safety of BAL in COVID patients and for healthcare providers. The study was carried out in 2021. It involved hospitalized patients in non-ICU wards at Careggi University Hospital in Florence, at CHU of Liege and at Morgagni Hospital Bologna University/Forli. All patients underwent BAL for microbiological and cytological analysis. Coinfections were detected in 35 out of 115 patients. In 34% of cases we demonstrated the presence of lymphocytic alveolitis;in 49% of cases a neutrophilic alveolitis and in 7% of cases we observed the presence of a mixed lymphocytic/neutrophilic alveolitis. All patients tested positive for Sars-Cov-2 PCR nasal swabs on admission. BAL was positive for Sars-Cov-2 in all cases, 7 PCR nasal swab performed at the time of the BAL were negative. No major adverse events were demonstrated in the 24 hours after BAL in enrolled patients. There were no cases of infection among health care workers involved in bronchoscopic procedures. Coinfections in COVID-19 patients are common. BAL is a safe tool to identify the presence of coinfections and help clinicians manage these patients correctly. BAL cellularity in covid patients shows a predominance of neutrophils, particularly in cases of co-infection. Our data suggests an earlier negativisation of nasopharyngeal swab compared to BAL.

The role of chest ct in understanding interstitial lung disease (ILD): Systemic sclerosis (SSC). versus COVID-19

Background: COVID-19 pandemic is a global emergency which may overlap on the clinical and radiological scenario of ILD in SSc. In clinical practice, the striking similarities observed at computed tomography (CT) between the diseases make it difficult to distinguish a COVID-19 superinfection from a progression of SSc-ILD. Objectives: The aim of our study was to identify the main CT features that may help distinguishing SSc-ILD from COVID-19 pneumonia. Methods: 22 international readers were included and divided in the radiologist group (RAD) and non-radiologist group (nRAD). The RAD group included nonchest RAD and chest-RAD. A total of 99 patients, 52 with COVID-19 and 47 with SSc-ILD, were included in the study. Results: Fibrosis inside focal ground glass opacities (GGO) in the upper lobes;fibrosis in the lower lobe GGO;reticulations in lower lobes (especially if bilateral and symmetrical or associated with signs of fibrosis) were the CT parameters most frequently associated with SSc-ILD. The CT parameters most frequently associated with COVID-19 pneumonia were: consolidation (CONS) in the lower lobes, CONS with peripheral (both central/peripheral or patchy distributions), anterior and posterior CONS and rounded-shaped GGOs in the lower lobes. After multivariate analysis, the presence of CONS in the lower lobes (p <0.0001) and signs of fibrosis in GGO in the lower lobes (p <0.0001) remained independently associated with COVID-19 pneumonia or SSc-ILD, respectively. These two variables were combined in a predictive score which resulted positively associated with the COVID-19 diagnosis, with 96.1% sensitivity and 83.3% specificity: 3 different risk class for COVID-19 pneumonia may be identified: high risk for COVID-19 pneumonia (5-9 points);probable overlap COVID-19 pneumonia in SSc-ILD (4 points);low risk for COVID-19 pneumonia (0-3 points). Conclusion: The CT differential diagnosis between COVID-19 Pneumonia and SSc-ILD is possible and may be fostered in practice by the use of a radiological score. In the case where an overlap of both diseases is suspected, the presence of consolidation in the lower lobes may suggest a COVID-19 pneumonia while the presence of fibrosis inside GGO may indicate a SSc-ILD.

The role of imaging in COVID-19 pneumonia diagnosis and management: Main positions of the experts, key imaging features and open answers

Lung imaging is widely involved in facing the coronavirus disease (COVID-19) pandemic. In fact, the COVID-19 infection may lead to a rapidly evolving and potentially fatal pneumonia. Moreover, computed tomography (CT) can be more sensitive than the COVID-19 reverse transcriptase-polymerase chain reaction test, especially at the beginning of the disease. Only patients with mild features consistent with COVID-19 infection, negative COVID-19 test, or positive COVID-19 test but at low risk for disease progression should avoid imaging. However, imaging becomes mandatory if respiratory symptoms worsen. A CT pattern classification has been designed to help both radiologists and clinicians. The typical pattern of COVID-19 is depicted by multifocal, bilateral, and peripheral ground-glass opacities (with or without consolidations or crazy paving) or findings of organizing pneumonia. Moreover, CT has demonstrated a prognostic role in patients with a diagnosis of COVID-19 pneumonia. Lung ultrasounds (LUS) are an emergent tool in the diagnosis of the disease. The adoption of LUS combined to chest X-rays in COVID-19 in pneumonia diagnosis is an interesting prospect that needs to be confirmed.

POS-720 Atypical Cause of Pancytopenia in a Kidney Transplant Patient

Introduction: We present the clinical case of a 71 years old man with chronic renal failure of unclear etiology. After 16 years of hemodialysis, he underwent successful deceased donor kidney transplantation 3 years ago. His immunosuppression included basiliximab, tacrolimus, mychophenolate and prednisone.3 years after transplant renal function was stable and in normal range, but there was evidence of anemia, thrombocytopenia and mild leukopenia;mycophenolate dose was reduced with no significant improvement. He developed low grade fever with urinary retention, requiring bladder catheterization;because of rapid deterioration of clinical picture, with dehydration and worsening of neurological status, he underwent hospitalization. Methods: Blood chemistry tests showed pancytopenia with high inflammatory indices, hyperkalemia, hyponatremia;PCR SARS-Cov2 in nasopharyngeal swab was negative. Brain CT was negative for acute lesions, chest CT showed minimal pleural effusion without lymphadenopathy. Empiric antibiotic therapy with piperacillin /tazobactam and ciprofloxacin was started and mycophenolate was discontinued.He was transferred to our facility. Hematological tests confirmed severe pancytopenia, worsening renal function, coagulopathy with increased INR and APTT, increased inflammatory indices, normal haptoglobin, slightly increased LDH, hypoalbuminemia and hypergammaglobulinemia (See Table).Urine culture was positive for an extended spectrum beta-lactamase E. Coli infection, and antibiotic therapy was targeted based on antibiogram. Abdomen CT showed splenomegaly (17 cm in diameter).Patient underwent hematological consult, and a diagnosis of disseminated intravascular coagulation (DIC) secondary to infection was made, excluding a primary hematological cause. Tacrolimus was discontinued and prednisone 5 mg was replaced with dexamethasone 20 mg/day.The search for bacteria and fungi on blood was negative, as well as viremia by PCR for CMV, EBV, Parvovirus B19, HHV8, VZV, HSV, BKV, JCV. HIV serology was negative. [Formula presented] Results: We considered the diagnosis of visceral leishmaniasis and bone marrow aspirate and Leishmania PCR research on peripheral blood and bone marrow were performed. Therapy with intravenous liposomal amphotericin B 4 mg /kg/day was started. Laboratory tests showed:Leishmania serology: positive (1: 2560 at indirect immunofluorescence titration IFAT)Leishmania PCR on blood: positive (1300 leish/ml)Leishmania PCR on bone marrow: positive 1,500,000,000 leish/ml)Bone marrow aspirate smear showed Leishmania amastigotes inside macrophages (Image). Patient was treated with Liposomal amphotericin for 12 consecutive days, with a total dose of 48 mg/kg. Dexamethasone was decreased and then switched to prednisone. Conclusions: Patient’s clinical condition significantly and rapidly improved, with resolution of fever, pancytopenia and coagulopathy, and dramatic decrease of Leishmania copies on blood. Two further doses of Liposomal Amphotericin were given weekly. Our case focuses on the importance of considering leishmaniasis in the differential diagnosis for fever with pancytopenia and coagulopathy, especially in countries where the disease is endemic. [Formula presented] Magnification (40x) of the bone marrow aspirate smear: the arrows indicate the presence of amastigotes. No conflict of interest