Page 510 - Textbook of Pathology, 6th Edition

494 4. Bird-breeders’ (Bird-fanciers’) lung occurs in pigeon 3. Secondary chronic pulmonary eosinophilia occurs
breeders, parrot breeders, chicken farmers and bird-fanciers secondary to adverse drug reactions; infection with fungi,
who are exposed to bird-droppings and danders from their bacteria, and helminths; allergic bronchopulmonary
feathers. aspergillosis and in association with asthma.
5. Mushroom-workers’ lung is found in mushroom 4. Idiopathic chronic eosinophilic pneumonia is
cultivators exposed to mushroom compost dust. characterised by prominent focal areas of consolidation of
6. Malt-workers’ lung is seen in distillery and brewery the lung. The condition is clinically diagnosed by excluding
workers who are exposed to mouldy barley and malt dust. other known causes of pulmonary eosinophilia.
7. Maple-bark disease occurs in those involved in stripping 5. Hypereosinophilic syndrome is occurrence of eosino-
of maple bark and inhale mouldy maple bark (maple tree is philia of over 1500/μl for more than 6 months without any
grown in northern hemisphere for timber and its leaf is the identifiable cause and without eosinophilic infiltrates in the
national emblem of Canada). lungs and other organs.
8. Silo-fillers’ disease occurs in individuals who enter the
silo (silo is an airtight store-house of fodder for farm animals) MORPHOLOGIC FEATURES. The lesions in the lungs
in which toxic fumes of nitric oxide and nitrogen dioxide are are similar in all cases of hypersensitivity pneumonitis.
formed due to fermentation of silage. The condition is Grossly, the lungs usually show patchy consolidation.
generally rapidly fatal; less often it may lead to ILD. Microscopically, there is thickening of the alveolar walls
by oedema and exudate, chiefly of eosinophils, and some
MORPHOLOGIC FEATURES. The pathologic changes lymphocytes and plasma cells. The alveolar lumina also
primarily involve the alveoli in contrast to bronchiolar contain eosinophils. Occasionally, small granulomas may
involvement in asthma. The changes vary depending upon be present.
whether the biopsy is examined in early stage or in late
stage. Goodpasture’s Syndrome
In early stage, the alveolar walls are diffusely infiltrated
with lymphocytes, plasma cells and macrophages. A Goodpasture’s syndrome or pulmonary haemorrhage
proportion of cases show granulomas consisting of syndrome is combination of necrotising haemorrhagic
histiocytes and giant cells of foreign body or Langhans’ interstitial pneumonitis and rapidly progressive
type. glomerulonephritis. The renal lesions of Goodpasture’s
SECTION III
In chronic cases, the lungs show interstitial fibrosis with syndrome are described in Chapter 22.
some inflammatory infiltrate. Honeycombing of the lung ETIOPATHOGENESIS. The condition results from
may be present. immunologic damage produced by anti-basement membrane
antibodies formed against antigens common to the
CLINICAL FEATURES. The clinical features vary according glomerular and pulmonary basement membranes. The
to the stage. In acute cases, there is generally sudden attack trigger for initiation of this autoimmune response is not clear;
of fever, myalgia, dyspnoea, cough and leucocytosis. In more it could be virus infection, exposure to hydrocarbons and
chronic cases, there are signs of slowly progressive smoking.
respiratory failure, dyspnoea and cyanosis as seen in other
interstitial lung diseases. MORPHOLOGIC FEATURES. Grossly, the lungs are
heavy with red-brown areas of consolidation.
Pulmonary Infiltrates with Eosinophilia Microscopically, the features vary according to the stage
Systemic Pathology
Pulmonary eosinophilia, eosinophilic pneumonias or of the disease:
pulmonary infiltration with eosinophilia (PIE) syndrome are In acute stage, there are focal areas of haemorrhages in
a group of immunologically-mediated lung diseases the alveoli and focal necrosis in the alveolar walls.
characterised by combination of 2 features: In more chronic cases, there is organisation of the
Infiltration of the lungs in chest radiographs. haemorrhage leading to interstitial fibrosis and filling of
Elevated eosinophil count in the peripheral blood. alveoli with haemosiderin-laden macrophages.
ETIOPATHOGENESIS. PIE syndrome has a number of CLINICAL FEATURES. The condition occurs commonly in
diverse causes and pathogenesis. These are as under: 2nd or 3rd decades of life with preponderance in males. The
1. Löeffler’s syndrome is characterised by eosinophilia in pulmonary manifestations generally precede the renal
the blood and typical wandering radiologic shadows, disease. Most cases present with haemoptysis accompanied
appearing in some part of the lung for a few days, and then with dyspnoea, fatigue, weakness and anaemia. Renal
disappearing to appear again somewhere else in the lung. manifestations soon appear which include haematuria,
The condition is generally self-limiting and mild, associated proteinuria, uraemia and progressive renal failure.
with slight fever and a few respiratory symptoms. The
etiology is unknown. Pulmonary Alveolar Proteinosis
2. Tropical pulmonary eosinophilia is caused by the Pulmonary alveolar proteinosis is a rare chronic disease in
passage of larvae of worms through the lungs e.g. in filariasis, which the distal airspaces of the lungs are filled with
ascariasis, strongyloidosis, toxocariasis and ancylostomiasis. granular, PAS-positive, eosinophilic material with abundant