necrotizing sarcoid-like granulomatosis
Introduction
Introduction to necrotizing sarcoidosis-like granulomatosis Necroticsarcoid granulomatosis (NSG) is a primary pulmonary granulomatous disease whose histopathology shows a fusion of sarcoidosis or epithelioid granulomatosis with vasculitis and large necrosis. As of 2002, there were only 120 cases of the disease reported abroad. At present, the pathogenesis of NSG is still unclear, and some scholars believe that it may be related to the immune mechanism. basic knowledge The proportion of illness: 0.001% Susceptible people: no specific population Mode of infection: non-infectious Complications: pneumonia colitis anal fistula rhinitis lupus erythematosus juvenile rheumatoid arthritis
Cause
Causes of necrotizing sarcoidosis-like granulomatosis
(1) Causes of the disease
The cause of NSG is unknown. It has been reported that fungal fragments are found in the granuloma of this disease, suggesting that the disease may be a variant of exogenous allergic inflammation.
(two) pathogenesis
Necrotizing nodular pathology showed small pulmonary nodular lesions, and the extent of lesion distribution and necrosis were lighter than Wegener's granulomatosis. Histological findings included: 1 fusion non-case granulomatous pneumonia; 2 necrosis , can be quite extensive; 3 vasculitis, the so-called "sarcoidosis-like granuloma" refers to epithelioid tissue cells in a circular agglomeration, with Langerhans giant cells and lymphocytes dotted, granuloma fusion forms a small lung parenchyma Nodules, pulmonary infiltrates resemble sarcoidosis, granulomatous lesions are distributed in the pleura, bronchial vascular bundles and interlobular septa, fused granulomas often invade the pleura, necrosis often varies in size, less central necrosis from coagulative necrosis Infarct necrosis from the foci to large areas, muscle arteries and veins involved in vasculitis, can have three forms, namely necrotic granuloma, giant cell vasculitis, infiltration of monocytes (including lymphocytes and macrophages), Ischemic necrosis of NSG is due to vasculitis leading to luminal obstruction.
Prevention
Necrotizing sarcoidosis-like granulomatosis prevention
(1) Strengthen nutrition and enhance physical fitness.
(2) Prevent and control infection and improve autoimmune function.
(3) Avoid wind and cold, avoid excessive fatigue, avoid alcohol and tobacco, and avoid spicy food.
Early diagnosis, understanding the infection, doing a good clinical observation, early detection of damage to various systems, early treatment, mainly to control infection.
Complication
Necrotic sarcoidosis-like granulomatosis complications Complications pneumonia colitis anal rhinitis lupus erythematosus juvenile rheumatoid arthritis
1. Repeated infections such as pneumonia, empyema, lung abscess, enteritis and colitis, can go to the anal fistula, common in the liver, spleen, lung and bone abscess, the occurrence of Aspergillus abscess in the brain, esophagus, small intestine and ureter can block.
2. Rhinitis, sinus stenosis, chronic diarrhea, delayed development of sick children, often resulting in short stature, with lupus erythematosus, juvenile rheumatoid arthritis.
Symptom
Symptoms of necrotizing sarcoidosis-like granulomatosis common symptoms sinus nodules chest pain, acute extrapulmonary symptoms, granuloma
Cough is a common symptom. Other symptoms include fever, chest pain, shortness of breath, discomfort and weight loss. The appearance of symptoms is related to extensive infiltration or small nodules in the lungs. 15% to 25% of patients are asymptomatic. Less involved, but there are reports in the literature that 13% of patients with extrapulmonary symptoms, including the eyes, brain and peripheral nerves, skeletal muscles and digestive tract.
Examine
Examination of necrotizing sarcoidosis-like granulomatosis
Pathological examination is the main basis for the diagnosis of this disease.
X-ray examination often changes to diffuse double lung or small pulmonary nodules or infiltration, about 1/3 of patients only show isolated unilateral small nodules, sometimes with pulmonary infiltration and cavity formation, typical NSG hilar lymphadenopathy Not common, but there are reports that are found in 79% of patients.
Diagnosis
Diagnosis and differentiation of necrotizing sarcoidosis-like granulomatosis
diagnosis
The diagnosis of NSG relies mainly on pathological examination. Its pathological features are: non-caseous necrotizing granuloma formation and necrotizing vasculitis. NSG granuloma consists of epithelial cells, lymphocytes, multinucleated giant cells, etc., and coagulative necrosis is seen in the center. Necrotic granuloma can directly invade the small vessel wall of the lung, leading to thickening of the vessel wall, stenosis or occlusion of the lumen, and the formation of vessel-centered infarct-like necrosis is a typical feature of NSG. PAS staining and acid-fast staining are negative, which can rule out granulomatous lesions caused by infection with specific pathogens. This case was diagnosed by pathological findings with both granuloma formation and necrotizing vasculitis.
Differential diagnosis
1. Wegener's granulomatosis NSG and Wegener's granuloma are difficult to distinguish. The pathology is mainly characterized by granuloma formation and necrosis. The difference is that the latter necrosis is more serious, the imaging is more common, and the lesion is malignant. With the involvement of the upper respiratory tract and the kidneys, the symptoms are more serious and the prognosis is worse. In addition, the ANCA test has a high positive rate in Wegener's granulomatosis, especially cytoplasmic (C)-ANCA, which is 95% positive in patients with advanced Wegener granulomatosis. In this case, the negative ANCA test and the clinical benign process did not support the diagnosis of Wegener's granuloma.
2. The relationship between sarcoidosis NSG and typical sarcoidosis is still unclear. They have similar clinical manifestations, pathological features and prognosis. Are they two subtypes of a disease or two independent diseases? there is controversy. The typical imaging findings of sarcoidosis are symmetrical mediastinal lymphadenopathy, small nodules and fibrosis along the airway, elevated ACE in blood and alveolar lavage fluid, high urinary calcium, and extrapulmonary performance compared with NSG. More common. The pathology of sarcoidosis is characterized by epithelial cells, multinucleated macrophages, and lymphocytes forming granuloma, but no cheese-like necrosis is characteristic. NSG coagulative necrosis is more pronounced than sarcoidosis.
3. Tuberculosis typical tuberculosis granuloma is caseous necrotizing granuloma, acid-fast staining can be positive, rare vascular inflammatory changes. The typical imaging changes are infiltration of the upper and lower lungs and the supraorbital region of the clavicle, fibrous tissue hyperplasia, and cavity-like changes.
4. Bronchial central granulomatous granulomatous lesions surround the bronchi and bronchioles, causing damage to the latter, but without vascular damage. In the imaging, the lesion becomes the main manifestation, not the nodular change.
5. Lymphoma-like granulomatous lymphoma pre-neoplastic lesions, mainly characterized by atypical hyperplasia of lymphocytes, showing a small amount of granulomatous changes, infiltrating cells mainly lymphocytes, plasma cells. Poor response to hormone therapy, chemotherapy has a good effect.
