Fatal cases of farmer's lung (FL) are rare.

Fatal cases of farmer's lung (FL) are rare. We rest based on death certificates, 13 cases of FL with a fatal issue in Finland between 1980 and 1990 Compared with incidence data from the years 1980 to 1982 the mortality was estimated as 07 percent forward average, death occurred 8 years after the diagnosis of FL undivided patient died acutely after a heavy mold outlook The other patients had chronic disease. Among them the immediate cause of death was pneumonia in seven patients, respiratory insufficiency in four, and pneumothorax in the same patient. The majority of these patients with a fatal issue had suffered from symptoms of FL for more than 1 year before the diagnosis was established and fibrotic changes were already visible in the chest radiograph at the time of the diagnosis. (Chest 1994; 106:509-12)

FVC = forced vital capacity

Acute farmer's lung (FL) usually has a fit prognosis. However, in some patients the disease leads to a chronic phase with pulmonary fibrosis that may lead to death.[1,2] A fatal case of acute FL has also been reported.[3] In long-term follow-up studies, the mortality associated with FL has ranged from 0 to 17 percent[14-9]

To assess the mortality of FL we have reviewed death certificates and clinical data of patients who had hypersensitivity pneumonitis as the underlying cause of death in Finland between the years of 1980 and 1990

Materials and Methods

In Finland, the death certificates are sent from the doctor signing the document to local and provincial medico-legal officers. After checking, the causes of death are registered in the Central Statistical Office. Death certificates were codfished according to a Finnish edition, 1969 of WHO International Classification of Diseases, 1967 eighth revision[10] up to 1986 and thereafter according to a Finnish edition, 1987 of WHO International Classification of Diseases, 1977 eighth revision.[11] Patients with hypersensitivity pneumonitis were searched for with the ICD digest 516 up to 1986 and with the ICD digest 495 thereafter. The code 516 in the Finnish Classification of Diseases, 1969 included pneumoconioses and lung diseases owed to nonorganic (excluding silicosis and asbestosis) and organic (including hypersensitivity pneumonitis) agents and passions The code 495 in the Finnish Classification of Diseases, 1987 included farmer's lung and other forms of hypersensitivity pneumonitis. The search with these digests revealed 22 death cases from 1980 to 1990 Permission to review the patient files of these patients was obtained from the Ministry of Social Affairs and Health.

For the diagnosis of FL each case had to fulfill the clinical criteria of FL[12] These criteria consisted of three main and six additional criteria. The main criteria were (1) outlook to offending antigens, revealed by way of history, by aerobiologic or microbiologic investigations of the environment, or the measurements of antigen-specific immunoglobulin G antibodies; (2) symptoms compatible with FL; and (3) lung infiltrations forward chest radiographs compatible with FL The additional criteria were (1) basal crepitant rales audible forward auscultation of the lungs, (2) impairment of pulmonary diffusing capacity, (3) arterial oxygen tension (or saturation) decreased either at cessation or during exercise, (4) restrictive ventilatory flaw in the spirometry, (5) histologic changes compatible with FL in a biopsy specimen from the lung and (6) positive provocation exhibition The diagnosis was considered confirmed if the patient fulfilled all the main criteria and at least brace of the additional criteria and if all other diseases with similar symptoms had been rul revealed If the criteria were otherwise fulfilled, yet the chest radiograph was normal, the diagnosis was considered confirmed if a lung biopsy was compatible with FL

The FL was considered as an underlying cause of death when the disease had progressioned to advanced pulmonary fibrosis and the immediate cause of death was respiratory, eg respiratory insufficiency or pneumonia. Also, the same case where the patient died acutely after a massive mold front which was confirmed as FL according to an autopsy was included.

Four of the 22 patients had not worked onward a farm. The causes of death in these four patients were hypersensitivity pneumonitis in a florist with a moldy basement floor in her workplace, and sarcoidosis, COPD and unspecified pneumoconiosis each in common patient. In addition, there was single in kind exfarmer, who had stopped farming years before the attack of the ultimately fatal disease. In this patient, lay open lung biopsy specimen was indicative of hypersensitivity pneumonitis, still the exact cause of the disease remained obscure

Thirteen of the 17 patients with farming history were considered to have FL as the underlying cause of death. revealed of the remaining four patients, sum of two units had FL but its contribution to the death remained uncertain. single in kind died suddenly at his family 2 months after the diagnosis of FL for an unknown reason. The other died 8 years after the diagnosis of FL proper to myopericarditis. One patient was regarded to have pulmonary fibrosis of unknown cause, individual died at the age of 81 from pulmonary fibrosis. In the latter case, there was a histologic suspicion of hypersensitivity pneumonitis in the autopsy, still there were no clinical data of possible exposing to causitive factors. Thus, 13 cases of death remained for final analysis.

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