Relative incidence of interstitial lung diseases in Brazil.

OBJECTIVE: To assess the relative frequency of incident cases of interstitial lung diseases (ILDs) in Brazil. METHODS: This was a retrospective survey of new cases of ILD in six referral centers between January of 2013 and January of 2020. The diagnosis of ILD followed the criteria suggested by international bodies or was made through multidisciplinary discussion (MDD). The condition was characterized as unclassifiable ILD when there was no specific final diagnosis following MDD or when there was disagreement between clinical, radiological, or histological data. RESULTS: The sample comprised 1,406 patients (mean age = 61 ± 14 years), and 764 (54%) were female. Of the 747 cases exposed to hypersensitivity pneumonitis (HP)-related antigens, 327 (44%) had a final diagnosis of HP. A family history of ILD was reported in 8% of cases. HRCT findings were indicative of fibrosis in 74% of cases, including honeycombing, in 21%. Relevant autoantibodies were detected in 33% of cases. Transbronchial biopsy was performed in 23% of patients, and surgical lung biopsy, in 17%. The final diagnoses were: connective tissue disease-associated ILD (in 27%), HP (in 23%), idiopathic pulmonary fibrosis (in 14%), unclassifiable ILD (in 10%), and sarcoidosis (in 6%). Diagnoses varied significantly among centers (c2 = 312.4; p < 0.001). CONCLUSIONS: Our findings show that connective tissue disease-associated ILD is the most common ILD in Brazil, followed by HP. These results highlight the need for close collaboration between pulmonologists and rheumatologists, the importance of detailed questioning of patients in regard with potential exposure to antigens, and the need for public health campaigns to stress the importance of avoiding such exposure.

Relative incidence of interstitial lung diseases in Brazil / Incidência relativa de doenças pulmonares intersticiais no Brasil

ABSTRACT Objective: To assess the relative frequency of incident cases of interstitial lung diseases (ILDs) in Brazil. Methods: This was a retrospective survey of new cases of ILD in six referral centers between January of 2013 and January of 2020. The diagnosis of ILD followed the criteria suggested by international bodies or was made through multidisciplinary discussion (MDD). The condition was characterized as unclassifiable ILD when there was no specific final diagnosis following MDD or when there was disagreement between clinical, radiological, or histological data. Results: The sample comprised 1,406 patients (mean age = 61 ± 14 years), and 764 (54%) were female. Of the 747 cases exposed to hypersensitivity pneumonitis (HP)-related antigens, 327 (44%) had a final diagnosis of HP. A family history of ILD was reported in 8% of cases. HRCT findings were indicative of fibrosis in 74% of cases, including honeycombing, in 21%. Relevant autoantibodies were detected in 33% of cases. Transbronchial biopsy was performed in 23% of patients, and surgical lung biopsy, in 17%. The final diagnoses were: connective tissue disease-associated ILD (in 27%), HP (in 23%), idiopathic pulmonary fibrosis (in 14%), unclassifiable ILD (in 10%), and sarcoidosis (in 6%). Diagnoses varied significantly among centers (c2 = 312.4; p < 0.001). Conclusions: Our findings show that connective tissue disease-associated ILD is the most common ILD in Brazil, followed by HP. These results highlight the need for close collaboration between pulmonologists and rheumatologists, the importance of detailed questioning of patients in regard with potential exposure to antigens, and the need for public health campaigns to stress the importance of avoiding such exposure.

RESUMO Objetivo: Avaliar a frequência relativa de casos incidentes de doenças pulmonares intersticiais (DPI) no Brasil. Métodos: Levantamento retrospectivo de casos novos de DPI em seis centros de referência entre janeiro de 2013 e janeiro de 2020. O diagnóstico de DPI seguiu os critérios sugeridos por órgãos internacionais ou foi feito por meio de discussão multidisciplinar (DMD). A condição foi caracterizada como DPI não classificável quando não houve um diagnóstico final específico após a DMD ou houve discordância entre dados clínicos, radiológicos ou histológicos. Resultados: A amostra foi composta por 1.406 pacientes (média de idade = 61 ± 14 anos), sendo 764 (54%) do sexo feminino. Dos 747 casos expostos a antígenos para pneumonite de hipersensibilidade (PH), 327 (44%) tiveram diagnóstico final de PH. Houve relato de história familiar de DPI em 8% dos casos. Os achados de TCAR foram indicativos de fibrose em 74% dos casos, incluindo faveolamento, em 21%. Autoanticorpos relevantes foram detectados em 33% dos casos. Biópsia transbrônquica foi realizada em 23% dos pacientes, e biópsia pulmonar cirúrgica, em 17%. Os diagnósticos finais foram: DPI associada à doença do tecido conjuntivo (em 27%), PH (em 23%), fibrose pulmonar idiopática (em 14%), DPI não classificável (em 10%) e sarcoidose (em 6%). Os diagnósticos variaram significativamente entre os centros (c2 = 312,4; p < 0,001). Conclusões: Nossos achados mostram que DPI associada à doença do tecido conjuntivo é a DPI mais comum no Brasil, seguida pela PH. Esses resultados destacam a necessidade de uma estreita colaboração entre pneumologistas e reumatologistas, a importância de fazer perguntas detalhadas aos pacientes a respeito da potencial exposição a antígenos e a necessidade de campanhas de saúde pública destinadas a enfatizar a importância de evitar essa exposição.