Pathology of Sarcoidosis and Differential Diagnostics of other Granulomatous Diseases

Granulomatous diseases are the heterogeneous group of the conditions of different etiologies with a variety of clinic syndromes and morphological features and nonuniform sensitivity to therapy, and the existence of granulomas as general dominate histological expression. Granuloma is indicative of chronic inflammation involving cells of the macrophage system and other inflammatory cells. After the antigen exposure, the activation of T-lymphocytes, macrophages, and epithelioid histiocytes leads to granuloma formation. Granuloma also contains the extracellular matrix produced by fibroblasts, which provide the boundary and isolation of antigen. Their etiology may classify granulomatous diseases as infectious and noninfectious. However, recent studies demonstrate that pathogenic microorganisms may cause the granuloma formation in diseases previously considered as noninfectious. In some cases, differentiation between infectious and noninfectious processes may be problematic. This chapter aims to highlight the multiformity of granulomatous diseases, characterize the pathologic features of different infectious and noninfectious granulomatosis, and delineate the diagnostic approach

Легочный вариант гистиоцитоза из клеток Лангерганса у пожилого мужчины

Langerhans cell histiocytosis (LCH) is a heterogeneous group of diseases with typical accumulation of Langerhans cells in different organs and tissues and formation of granulomas with eosinophil infiltration. Pulmonary LCH in adults is an orphan interstitial lung disease. This disease could occur independently on 15% or to be a part of a multisystemic disease in similar proportion of cases. The clinical course of LCH is various and unpredictable and could vary from asymptomatic course to severe progressive pulmonary injury and respiratory failure. The disease could regress spontaneously in a quarter of patients; have the stable course in 50% and progress in 25% of patients. A case of early-stage pulmonary LCH in a 73-year-old smoker was reported in the article. The diagnose was made according to histological and immunohistochemical investigations of VATS biopsy of the lung tissue. Disseminated injury of the lungs without cysts was found that is typical for early stage of LCH and is difficult for detection. Radiological follow-up revealed rapid progression of the disease.Гистиоцитоз из клеток Лангерганса (ГКЛ) – гетерогенная группа заболеваний, характеризующихся накоплением клеток Лангерганса в различных органах и тканях с формированием гранулем с эозинофильной инфильтрацией. Легочный вариант ГКЛ у взрослых относится к редким интерстициальным заболеваниям легких. В 15 %наблюдений может развиться самостоятельное заболевание, с той же частотой ГКЛ является проявлением мультисистемного заболевания. Течение ГКЛ разнообразно и непредсказуемо – от бессимптомных форм до тяжелого прогрессирующего поражения легких, сопровождающегося дыхательной недостаточностью. У #¼ пациентов наблюдается самопроизвольный регресс, у 50 % – стабильное течение заболевания, у 25 % –прогрессирование. Приводится наблюдение гистиоцитоза легких у курящего мужчины 73 лет на ранней стадии развития заболевания, выявленного на основании гистологического и иммуногистохимического исследования привидеоторакоскопической биопсии легкого. В данном наблюдении описано очаговое диссеминированное поражение легких без кистозных изменений верхних и средних долей легких, что характерно для начальной фазы развития ГКЛ, сложной для диагностики. Динамическое рентгенологическое наблюдение свидетельствует о быстропрогрессирующем течении заболевания

Accelerated Growth, Differentiation, and Ploidy with Reduced Proliferation of Right Ventricular Cardiomyocytes in Children with Congenital Heart Defect Tetralogy of Fallot

The myocardium of children with tetralogy of Fallot (TF) undergoes hemodynamic overload and hypoxemia immediately after birth. Comparative analysis of changes in the ploidy and morphology of the right ventricular cardiomyocytes in children with TF in the first years of life demonstrated their significant increase compared with the control group. In children with TF, there was a predominantly diffuse distribution of Connexin43-containing gap junctions over the cardiomyocytes sarcolemma, which redistributed into the intercalated discs as cardiomyocytes differentiation increased. The number of Ki67-positive cardiomyocytes varied greatly and amounted to 7.0–1025.5/106 cardiomyocytes and also were decreased with increased myocytes differentiation. Ultrastructural signs of immaturity and proliferative activity of cardiomyocytes in children with TF were demonstrated. The proportion of interstitial tissue did not differ significantly from the control group. The myocardium of children with TF under six months of age was most sensitive to hypoxemia, it was manifested by a delay in the intercalated discs and myofibril assembly and the appearance of ultrastructural signs of dystrophic changes in the cardiomyocytes. Thus, the acceleration of ontogenetic growth and differentiation of the cardiomyocytes, but not the reactivation of their proliferation, was an adaptation of the immature myocardium of children with TF to hemodynamic overload and hypoxemia

Predictors of Progression and Mortality in Patients with Chronic Hypersensitivity Pneumonitis: Retrospective Analysis of Registry of Fibrosing Interstitial Lung Diseases

Hypersensitivity pneumonitis (HP) is an interstitial lung disease (ILD) resulting from an immune-mediated response in susceptible and sensitized individuals to a large variety of inhaled antigens. Chronic HP with a fibrotic phenotype is characterized by disease progression and a dismal prognosis. The aim of this study was to identify predictors of progression and mortality in patients with chronic HP in real clinical practice. Materials and methods: This retrospective, multicenter, observational study used data from a registry of 1355 patients with fibrosing ILDs. The study included 292 patients diagnosed with chronic HP based on the conclusion of a multidisciplinary discussion (MDD). Results: The patients were divided into groups with progressive (92 (30.3%) patients) and nonprogressive pulmonary fibrosis (200 (69.7%) patients). The most significant predictors of adverse outcomes were a DLco < 50% predicted, an SpO2 at the end of a six-minute walk test (6-MWT) < 85%, and a GAP score ≥ 4 points. Conclusion: Pulmonary fibrosis and a progressive fibrotic phenotype are common in patients with chronic HP. Early detection of the predictors of an adverse prognosis of chronic HP is necessary for the timely initiation of antifibrotic therapy