Abstract
Hypersensitivity pneumonitis (HP) classified as an interstitial lung disease is characterized by a complex immunological reaction of the lung parenchyma in response to repetitive inhalation of a sensitized allergen. The estimated worldwide incidence of hypersensitivity pneumonitis is extremely rare and highly dependent on climatic, geographical, occupational and industrial factors. It might be secondary to a domestic or professional exposure, usually occurs in people who work in places where there are high levels of dust, fungus, or molds. Long-term exposure can lead to lung inflammation and acute lung disease. Over time, the acute condition turns into long-lasting (chronic) lung disease. Thus, we distinguish 2 mains aspects fibrotic HP and Nonfibrotic HP. The diagnosis of HP maybe sophisticated especially in fibrotic form. The prognosis of this disease depends on early diagnosis with complete antigen avoidance and most often corticosteroid therapy.
This work aims to study the epidemiological, clinical, paraclinical aspects of hypersensitivity pneumonitis as well as therapeutic management, through a series of eight cases of HP carried out at the Pulmonology Department 20 August 1953, University Hospital Center IBN ROCHD, between January 2020 and January 2022, analyzed using a pre-established exploitation sheet. The average age of the patients studied was 51 years with a female predominance (sex-ratio M/F= 0.34). Domestic and occupational exposures of our patients were equal. The clinical symptomatology is dominated by almost constant dyspnea in all patients. Physical signs increased by crackles, objectified in 75% of patients. Computed tomography (CT) remains a great diagnostic contribution. Thus, allowing to have two categories of patients, depending on the presence or absence of signs of pulmonary fibrosis.
In our study, five patients had fibrotic HP, and three cases had non- fibrotic HP. Precipitins were positive. Plethysmography objectified a restrictive ventilatory disorder in 62.5%. All patients benefited from antigenic eviction with long-term corticosteroid therapy. The evolution was favorable in 87.5% of cases.