**2.2 Chronic allergic disease caused by metals**

Chronic berylliosis is an allergic granulomatosis. Granulomas are similar to those in sarcoidosis and may be slightly larger. As in sarcoidosis, granulomas have perilymphatic location, and lymph nodes are usually affected. The same variant of granulomatosis may develop as a result of zirconium exposure. The diagnosis should be based on the clinical history and lymphocyte transformation test [9].

### **2.3 Polyangiit with granulomatosis**

In our opinion, of particular difficulty is **the differential diagnosis of necrotizing granulomatosis**. Infectious disease, as one of the most common causes of necrotizing granulomatosis, should be differentiated from polyangiitis with granulomatosis (previously Wegener's granulomatosis), aspiration pneumonia, and less often from nodular form of rheumatoid arthritis, necrotizing sarcoid granulomatosis (NSG), lung infarction, and lymphomatoid granulomatosis [10]. Despite the specific histological changes in these diseases, there is, however, an overlap, and only a combination of histological features help in the final diagnosis. **Infectious necrotizing granuloma** usually has smooth contours, commonly eosinophilic necrosis, surrounded by a rim of histiocytes and giant multinucleated cells. By contrast, in polyangiitis with granulomatosis, the necrosis zone has uneven contours resembling a geographical map, with a large amount of cellular debris, which gives the necrosis a "dirty" appearance (**Figure 7**).

Necrotic areas are also surrounded by a histiocytic rim; however, giant cells are usually few in number and are scattered without forming compact granulomas. A characteristic feature of polyangiitis with granulomatosis is the necrotizing vasculitis with fibrinoid necrosis of the media (**Figure 8**);

**53**

**Figure 8.**

**Figure 7.**

granulomatosis [11].

*Pathology of Sarcoidosis and Differential Diagnostics of other Granulomatous Diseases*

Such vessels are observed in the inflammation; the damage to the vessel wall is often eccentric; also, the branches of the pulmonary arteries and veins are affected in this disease. The capillaritis, accompanied by intra-alveolar hemorrhages, may also be observed. Necrotizing vasculitis may often be found in the inflammation and necrosis, but this is also in the infectious granulomatosis; therefore, to confirm the diagnosis of polyangiitis with granulomatosis, it is necessary to carefully evaluate the vessels outside necrosis, and additional stains are recommended to identify elastic tissue (Verhoeff-van Gieson stain and others). In contrast to infectious granulomatosis, lymph node involvement is not typical for polyangiitis with

*Polyangiit with granulomatosis: Fibrinoid necrosis of the vessel wall with lymphocytic infiltration. H&E.*

*DOI: http://dx.doi.org/10.5772/intechopen.90693*

*Polyangiit with granulomatosis: "geographic" necrosis with cell debris. H&E.*

*Pathology of Sarcoidosis and Differential Diagnostics of other Granulomatous Diseases DOI: http://dx.doi.org/10.5772/intechopen.90693*

**Figure 7.** *Polyangiit with granulomatosis: "geographic" necrosis with cell debris. H&E.*

#### **Figure 8.**

*Sarcoidosis and Granulomatosis - Diagnosis and Management*

usual interstitial pneumonia, only scattered giant cells or remnants of granulomas may be found in the fibrotic areas or in the honeycomb zones in hypersensitivity

*Hypersensitivity pneumonitis: Ill-defined granuloma consisting of giant multinucleated cells with needle-like* 

*structures surrounded by lymphocytes, lymphocytic infiltration of interalveolar septa. H&E.*

Chronic berylliosis is an allergic granulomatosis. Granulomas are similar to those in sarcoidosis and may be slightly larger. As in sarcoidosis, granulomas have perilymphatic location, and lymph nodes are usually affected. The same variant of granulomatosis may develop as a result of zirconium exposure. The diagnosis should be based on the clinical history and lymphocyte transformation test [9].

In our opinion, of particular difficulty is **the differential diagnosis of necrotizing granulomatosis**. Infectious disease, as one of the most common causes of necrotizing granulomatosis, should be differentiated from polyangiitis with granulomatosis (previously Wegener's granulomatosis), aspiration pneumonia, and less often from nodular form of rheumatoid arthritis, necrotizing sarcoid granulomatosis (NSG), lung infarction, and lymphomatoid granulomatosis [10]. Despite the specific histological changes in these diseases, there is, however, an overlap, and only a combination of histological features help in the final diagnosis. **Infectious necrotizing granuloma** usually has smooth contours, commonly eosinophilic necrosis, surrounded by a rim of histiocytes and giant multinucleated cells. By contrast, in polyangiitis with granulomatosis, the necrosis zone has uneven contours resembling a geographical map, with a large amount of cellular debris, which gives

Necrotic areas are also surrounded by a histiocytic rim; however, giant cells are usually few in number and are scattered without forming compact granulomas. A characteristic feature of polyangiitis with granulomatosis is the necrotizing vasculi-

**52**

pneumonitis [8].

**Figure 6.**

**2.2 Chronic allergic disease caused by metals**

**2.3 Polyangiit with granulomatosis**

the necrosis a "dirty" appearance (**Figure 7**).

tis with fibrinoid necrosis of the media (**Figure 8**);

*Polyangiit with granulomatosis: Fibrinoid necrosis of the vessel wall with lymphocytic infiltration. H&E.*

Such vessels are observed in the inflammation; the damage to the vessel wall is often eccentric; also, the branches of the pulmonary arteries and veins are affected in this disease. The capillaritis, accompanied by intra-alveolar hemorrhages, may also be observed. Necrotizing vasculitis may often be found in the inflammation and necrosis, but this is also in the infectious granulomatosis; therefore, to confirm the diagnosis of polyangiitis with granulomatosis, it is necessary to carefully evaluate the vessels outside necrosis, and additional stains are recommended to identify elastic tissue (Verhoeff-van Gieson stain and others). In contrast to infectious granulomatosis, lymph node involvement is not typical for polyangiitis with granulomatosis [11].
