Aims and objectives
Granulomatous Lung Diseases (GLD) comprises a wide range of infectious and non-infectious pathologies that present the same pattern of chronic inflammatory response [1].
The granulomas emerge after an attempt of the cellular immune response to contain an agent of difficult eradication.
Histologically,
granulomas consist of an aggregation of macrophages that transform into epithelioid cells,
surrounded by monocytes – mainly lymphocytes [2].
Mycobacterial and fungal infections are the most common infectious causes of GLD,
including tuberculosis (TB),
nontuberculous mycobacteriosis,
Histoplasma,
Cryptococcus,
Coccidioides,
Blastomyces and Aspergillus [2]....
Methods and materials
Patient population:
In this retrospective study,
all 994 consecutive lung biopsies performed between January 2013 and December 2017 in our institution,
a tertiary hospital located in Sao Paulo,
Brazil,
were retrieved from hospital records.
All samples were collected by intra-operative biopsy,
bronchoscopy with transbronchial biopsy or percutaneous CT-guided needle biopsy.
This study was approved by institutional and national ethics committees.
Due to the retrospective nature of the study,
the informed consent was not necessary.
The inclusion criteria was the existence of granulomatous lesions in the...
Results
The study population of 75 cases consisted of 49,3% men (37/75) and 50,7% women (38/75).
The median age was 59 (range 18-96).
The majority of samples were obtained by CT-guided biopsy (47/75,
62.7%),
23 (30.7%) by intra-operative biopsy and five (6.7%) were acquired by bronchoscopy.
Etiology
The table below summarizes the etiologies of GLD in our study population. Infection was the most common cause of GLD (47/75,
62.7%),
non-infectious causes occurred in 13.3% (10/75) and GLUS corresponded to 24% (18/75) of the cases.
Among infectious...
Conclusion
Despite considered a high TB burden country by World Health Organization [8],
in our study,
held in one single tertiary hospital located in Sao Paulo,
Brazil,
Histoplasma infection was more frequent than tuberculosis among biopsy proven GLD.
Mukhopadhyay et al [9] reviewed the causes of GLD in 7 different countries,
including Brazil.
On this study population,
tuberculosis occurred in 13 of 50 cases of GLD from Brazil (26.0%),
and none of the Brazilian cases was due to histoplasmosis,
which was diagnosed exclusively in the USA....
References
1.
Zhu Q,
Xu X,
Li M,
Wang X.
Analysis of chest computed tomography manifestations of non-Mycobacterium tuberculosis induced granulomatous lung diseases.
Radiology of Infectious Diseases.
2017:157 - 63.
2.
Ohshimo S,
Guzman J,
Costabel U,
Bonella F.
Differential diagnosis of granulomatous lung disease: clues and pitfalls: Number 4 in the Series "Pathology for the clinician" Edited by Peter Dorfmüller and Alberto Cavazza.
Eur Respir Rev.
2017;26(145).
3.
Mukhopadhyay S,
Gal AA.
Granulomatous lung disease: an approach to the differential diagnosis.
Arch Pathol Lab Med....