538. Rate of Infectious Etiologies in Patients with Necrotizing and Non-necrotizing Granulomas on Lung Biopsy
Session: Poster Abstract Session: Tuberculosis Epidemiology and Diagnosis
Thursday, October 27, 2016
Room: Poster Hall
Background:  Limited data exist on the frequency of infectious etiologies among patients with necrotizing and non-necrotizing granulomas identified on histologic examination of lung tissue specimens.

Methods: We reviewed all adult patients who had necrotizing or non-necrotizing granulomas identified upon pathological examination of a lung biopsy specimen between January 2008 and July 2015. Demographic and clinical information was obtained through retrospective review of the patients’ medical records; we also reviewed all microbiology reports and results of radiological studies. The Pearson's chi-square test or the Fisher's exact tests were performed to compare categorical variables (P<0.05).

Results:  A total of 104 patients were included. The median age of the cohort was 59 (range 22 to 91) years, and 57 (55%) were male. A lung specimen was obtained by surgical exploration in 60 (58%) patients, 44 (42%) had a percutaneous biopsy. Thirty-two (31%) patients had a current or distant history of malignancy, 19 (18%) had diabetes mellitus, 11 (11%) chronic obstructive pulmonary diseases, and 22 (21%) were current smokers. Five (5%) patients received antibiotics within thirty days before biopsy. The most common radiological presentations were a pulmonary nodule (58%) or opacity (20%). On biopsy, a necrotizing granuloma was found in 30 (29%), a non-necrotizing in 74 (71%) patients. Tuberculosis (n=7) and non-tuberculous mycobacterial disease (n=13) was diagnosed in 20 (19%) patients, a fungal etiology (Aspergillus, Cryptococcus, or Blastomyces) was identified in 5 (5%) patients, one patient had Nocardia. Any infectious etiology was more common among patients with necrotizing granulomas (37%) than those with non-necrotizing granulomas (20%; P=0.08). The most common non-infectious etiologies were malignancy (18%) and sarcoidosis (17%).

ConclusionAn infectious etiology comprising mycobacteria, fungus, and Nocardia species was found among twenty-five percent of patients with granulomatous disease of the lung. Infection was found more frequently among patients with necrotizing than patients with non-necrotizing granulomas; however, the difference was not statistically significant.

Jun Makino, MD1, Tina Wang, MD2, Takaaki Kobayashi, M.D.3, Berilonson Osiro, MD1, Young-Gwang Jeong, MD1, Sonal Bajaj, MD1 and Jorg Ruhe, MD4, (1)Infectious Diseases, Mount Sinai Beth Israel Medical Center, New York, NY, (2)Department of Internal Medicine, Mount Sinai Beth Israel, New York, NY, (3)Medicine, Mount Sinai Beth Israel Medical Center, New York, NY, (4)Infectious Diseases, Mount Sinai Beth Israel, Icahn School of Medicine at Mount Sinai, New York, NY

Disclosures:

J. Makino, None

T. Wang, None

T. Kobayashi, None

B. Osiro, None

Y. G. Jeong, None

S. Bajaj, None

J. Ruhe, None

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