Severe Chlamydia psittaci pneumonia: clinical characteristics and risk factors

Abstract

Background: Psittacosis ranges from a mild illness to fulminant severe pneumonia with multi-organ failure.It's crucial to understand the clinical characteristics and identify risk factors for a better outcome. Methods:We conducted a retrospective analysis designed to identify risk factors for severe Chlamydia psittaci pneumonia (C. psittaci pneumonia) by comparing the clinical characteristics of patients with severe and less severe forms of the disease. Epidemiological, clinical, laboratory, computed tomography (CT) imaging, and outcome data were collected.Results: We enrolled 27 patients with C. psittaci pneumonia, with a median age of 63 (range, 47-82) years, and 23 of whom (85.2%) had a history of avian exposure. Dyspnea was seen in 15 patients with severe C. psittaci pneumonia (100%), and four in 12 non-severe patients (33.3%) (P<0.01). Compared to nonsevere patients, those with severe C. psittaci pneumonia had significantly higher levels of procalcitonin, urea nitrogen, lactate dehydrogenase, creatine kinase (CK), B natriuretic peptide (BNP), myoglobin, IL-6, and IL-10, as well as lower lymphocyte and CD8+ T cell counts, and P a O 2 /F i O 2 ratio. Among patients with severe infection, CT showed that 46.7% had multi-lobar (more than two lobes) pneumonia, whereas its incidence was 0% in non-severe patients (P=0.01). Multivariate analysis revealed that the independent risk factors associated with severe C.

Clinical, radiological and pathological characteristics of moderate to fulminant psittacosis pneumonia

“…There were more male than female of patients with psittacosis pneumonia in this study, in accord with the previous study [ 4 ]. This may be associated with occupational exposure, such as feeding or killing poultry.…”

“…Diagnostic criteria for psittacosis pneumonia were as follows: (1) meeting the diagnostic criteria for CAP or severe CAP [ 12 ], (2) specific reads of C . psittaci genome were detected in BALF or blood samples via mNGS, (3) other etiologies were ruled out by routine diagnostic methods, including culture of blood, sputum, and BALF [ 4 ].…”

Clinical Symptoms and Outcomes of Severe Pneumonia Caused by Chlamydia psittaci in Southwest China

“…MYO≥300ng/mL and HS-TNTi ≥50ng/L were one of the high-risk death factors in patients with chlamydia psittaci pneumonia. In previous reports, the increase of ( Su et al., 2021 ) CK was a high risk factor for severe chlamydia psittaci pneumonia. Our study further proved that not only CK, MYO and HS-TNTI related to myocardial enzymes were also high risk factors for severe patients, suggesting that myocardial injury caused by Chlamydia psittaci is not rare in clinic.…”

“…In this retrospective study, we included 27 cases of severe C. psittaci pneumonia diagnosed by mNGS in the ICU of four tertiary A hospitals in southwest China from May 2018 to March 2020. The diagnostic criteria of C. psittaci pneumonia refer to previous literature reports ( Su et al., 2021 ). We recorded data on age, sex, exposure history, comorbidities, onset course, symptoms, signs, imaging, laboratory examination, method of diagnosis, treatment, and clinical outcomes.…”

Diagnostic Value of Metagenomic Next-Generation Sequencing of Bronchoalveolar Lavage Fluid for the Diagnosis of Suspected Pneumonia in Immunocompromised Patients

“…Rencently, an amount of cases of Chlamydia psittaci infection have been reported (23,24). In our study, we have diagnosed 2 patients of Chlamydia psittaci infection solely by mNGS because of the lack of CMTs for Chlamydia psittaci and they were improved with a proper treatment.…”