Criterios histopatológicos para el diagnóstico de fibrosis pulmonar idiopática / Histopathological criteria for the diagnosis of idiopathic pulmonary fibrosis

En la última actualización de las Guías de Práctica Clínica de la ATS/ERS/JRS/ALAT de fibrosis pulmonar idiopática (FPI) se propone una nueva forma de clasificar los patrones histopatológicos en 4 tipos: definitivo de neumonía intersticial usual (NIU), probable NIU, indeterminado y alternativo a NIU. Una remodelación fibrótica heterogénea de la arquitectura normal del parénquima pulmonar, con cicatrización destructiva en forma de "panal de abejas", presencia de focos fibroblásticos y distribución predominantemente subpleural y paraseptal, con escaso infiltrado inflamatorio intersticial de tipo crónico, asociado a la ausencia de elementos sugerentes de causas secundarias como distribución bronquiolocéntrica, predominio de infiltrados intersticiales inflamatorios o granulomas mal formados, permite un diagnóstico certero de FPI en un escenario clínico-radiológico adecuado.

In the latest update of the ATS/ERS/JRS/ALAT Clinical Practice Guidelines for idiopathic pulmonary fibrosis (IPF), a new way of classifying histopathological patterns in 4 types is proposed: definitive usual interstitial pneumonia (UIP), probable UIP, indeterminate and alternative to UIP. A heterogeneous fibrotic remodeling of the normal architecture of the pulmonary parenchyma, with destructive scarring in the form of "honeycomb", presence of fibroblastic foci and predominantly subpleural and paraseptal distribution, with scarce chronic interstitial inflammatory infiltrate, associated with the absence of elements suggestive of secondary causes such as bronchiolocentric distribution, predominance of inflammatory interstitial infiltrates or poorly formed granulomas, allows an accurate diagnosis of IPF in an appropriate clinical-radiological scenario.

Severity classification for idiopathic pulmonary fibrosis by using fuzzy logic

OBJECTIVE: To set out a severity classification for idiopathic pulmonary fibrosis (IPF) based on the interaction of pulmonary function parameters with high resolution computed tomography (CT) findings. INTRODUCTION: Despite the contribution of functional and radiological methods in the study of IPF, there are few classification proposals for the disease based on these examinations. METHODS: A cross-sectional study was carried out, in which 41 non-smoking patients with IPF were evaluated. The following high resolution CT findings were quantified using a semi-quantitative scoring system: reticular abnormality, honeycombing and ground-glass opacity. The functional variables were measured by spirometry, forced oscillation technique, helium dilution method, as well as the single-breath method of diffusing capacity of carbon monoxide. With the interaction between functional indexes and high resolution CT scores through fuzzy logic, a classification for IPF has been built. RESULTS: Out of 41 patients studied, 26 were male and 15 female, with a mean age of 70.8 years. Volume measurements were the variables which showed the best interaction with the disease extension on high resolution CT, while the forced vital capacity showed the lowest estimative errors in comparison to total lung capacity. A classification for IPF was suggested based on the 95 percent confidence interval of the forced vital capacity percent: mild group (>92.7); moderately mild (76.9-92.6); moderate (64.3-76.8 percent); moderately severe (47.1-64.2); severe (24.3-47.0); and very severe (<24.3). CONCLUSION: Through fuzzy logic, an IPF classification was built based on forced vital capacity measurement with a simple practical application.