Background: Fibrotic hypersensitivity pneumonitis (fHP) shares many features with other fibrotic interstitial lung diseases (ILD), and as a result it can be misdiagnosed as idiopathic pulmonary fibrosis (IPF). We aimed to determine the value of bronchoalveolar lavage (BAL) total cell count (TCC) and lymphocytosis in distinguishing fHP and IPF and to evaluate the best cut-off points discriminating these two fibrotic ILD. Methods: A retrospective cohort study of fHP and IPF patients diagnosed between 2005 and 2018 was conducted. Logistic regression was used to evaluate the diagnostic utility of clinical parameters in differentiating between fHP and IPF. Based on the ROC analysis, BAL parameters were evaluated for their diagnostic performance, and optimal diagnostic cut-offs were established. Results: A total of 136 patients (65 fHP and 71 IPF) were included (mean age 54.97 ± 10.87 vs. 64.00 ± 7.18 years, respectively). BAL TCC and the percentage of lymphocytes were significantly higher in fHP compared to IPF (p < 0.001). BAL lymphocytosis >30% was found in 60% of fHP patients and none of the patients with IPF. The logistic regression revealed that younger age, never smoker status, identified exposure, lower FEV₁, higher BAL TCC and higher BAL lymphocytosis increased the probability of fibrotic HP diagnosis. The lymphocytosis >20% increased by 25 times the odds of fibrotic HP diagnosis. The optimal cut-off values to differentiate fibrotic HP from IPF were 15 × 10⁶ for TCC and 21% for BAL lymphocytosis with AUC 0.69 and 0.84, respectively. Conclusions: Increased cellularity and lymphocytosis in BAL persist despite lung fibrosis in HP patients and may be used as important discriminators between IPF and fHP.

Background: Amyloidosis is an uncommon condition, which results from accumulation of misfolded extracellular insoluble protein in tissues and organs of the body, causing its damage and dysfunction. Histologically, after staining with Congo red, the amyloid deposits show an apple-green birefringence under polarized light microscope. Amyloidosis can affect all organ systems and is classified into hereditary or acquired, localized or systemic. Respiratory involvement occurs in 50% of the patients with amyloidosis and it may take tracheobronchial, nodular parenchymal, diffuse alveolar septal and lymphatic forms. Methods: We report four cases of pulmonary amyloidosis. A female patient with localized form of tracheobronchial and nodular parenchymal pulmonary amyloidosis, which was initially misdiagnosed as sarcoidosis. A male patient who was referred to our department for further evaluation of multiple tumors in lungs accompanied by mediastinal lymphadenopathy, liver and peritoneal tumors. A male patient with suspect of lung malignancy. A male patient with diagnosed idiopathic pulmonary fibrosis and the possibility of malignancy. Results: All the diagnoses were established by demonstration of amyloid protein in tissue specimens obtained in transbronchial or open lung biopsies. Conclusions: Due to its nonspecific clinical and radiological findings, amyloidosis can often mimic other diseases and should be considered as one of the differential diagnoses. In order to confirm the diagnosis, proving the presence of amyloid deposition with positive Congo red staining in respiratory specimen is mandatory.

Lipoid pneumonia is a rare pulmonary disease, classified in terms of the source of lipid exposure into two variants: exogenous and endogenous. We present a patient with exogenous lipoid pneumonia, acquired after chronic exposure to paraffin oil-containing nasal drops. The diagnosis was established by demonstration of lipid-laden macrophages in bronchoalveolar lavage, chest computed tomography results and a history of lipid exposure.

Sarcoidosis is a systemic, granulomatous disease of unknown etiology, most often manifested by mediastinal and hilar lymph node enlargement and parenchymal nodules in the lungs. However, it may involve any other organ. Neuro-sarcoidosis, a condition that affects up to 20% of sarcoidosis patients, can be found in any part of the central or peripheral nervous system and has important ophthalmic and neuro-ophthalmic manifestations. We present two patients with sudden vision loss due to neurosarcoidosis. In both cases, biopsy of the mediastinal lymph node showed non-caseating granulomas consistent with sarcoidosis. Treatment involved high doses of methylprednisolone intravenously, followed by topical dexamethasone eye drops in the first case and a systemic steroid treatment in the second, resulting in symptom relief. Those two cases demonstrate that sarcoidosis should be considered as a differential diagnosis in cases of optic neuritis.

The onset of the COVID-19 pandemic allowed physicians to gain experience in lung ultrasound (LUS) during the acute phase of the disease. However, limited data are available on LUS findings during the recovery phase. The aim of this study was to evaluate the utility of LUS to assess lung involvement in patients with post-COVID-19 syndrome. This study prospectively enrolled 72 patients who underwent paired LUS and chest CT scans (112 pairs including follow-up). The most frequent CT findings were ground glass opacities (83.3%), subpleural lines (72.2%), traction bronchiectasis (37.5%), and consolidations (31.9%). LUS revealed irregular pleural lines as a common abnormality initially (56.9%), along with subpleural consolidation >2.5 mm ≤10 mm (26.5%) and B-lines (26.5%). A strong correlation was found between LUS score, calculated by artificial intelligence percentage involvement in ground glass opacities described in CT (r = 0.702, p < 0.05). LUS score was significantly higher in the group with fibrotic changes compared to the non-fibrotic group with a mean value of 19.4 ± 5.7 to 11 ± 6.6, respectively (p < 0.0001). LUS might be considered valuable for examining patients with persistent symptoms after recovering from COVID-19 pneumonia. Abnormalities identified through LUS align with CT scan findings; thus, LUS might potentially reduce the need for frequent chest CT examinations.

Introduction: While lung ultrasonography (LUS) has been widely used in the acute phase of COVID-19 pneumonia, there is not enough information available to assess the diagnostic value of LUS in post-COVID-19 and its relation to pulmonary function tests (PFTs). Methods: Sixty-seven patients (female-24; male-43; mean age of 57.5±13 years) with persistent clinical symptoms after COVID-19 pneumonia were prospectively enrolled and underwent PFTs and LUS. The LUS examination was performed with a linear transducer to score various artifacts on a pleural line and a 12-zone scoring system was implemented (total score ranged between 0 and 36 points). Results: In total 101 pairs of both LUS examinations and PFTs were performed (67 patients underwent one assessment, 32- a second and 2- a third follow-up assessment). The mean time from the onset of COVID-19 until enrolment was 277± 189 days. Alterations in DLCO and FVC (<80% of the lower limit of normal) were detected in 55 cases (54.5%) and 20 cases (19.8%), respectively. The mean LUS score was 11.7±7.14 and exhibited a moderate negative correlation with DLCO (r= -0.56), FVC (r= -0.42), FEV1 (r= -0,43), and a weak negative correlation with TLC (r= -0.39), p<0,05 respectively. Patients with confirmed fibrotic-like lesions showed significantly lower DLCO scores (p=0. 000001). Conclusions: The LUS severity score was inversely related to PFTs results. A higher degree of lung involvement in LUS was associated with poorer lung function; thus, LUS might be considered as a screening tool for follow-up examinations in post-COVID-19 survivors.