Acute or subacute progressive interstitial pneumonia

High-Dose Tigecycline for the Treatment of Progressive Pneumonia Caused by Chlamydia psittaci: Case Series and Literature Review

Purpose

To summarize the clinical characteristics of progressive pneumonia caused by Chlamydia psittaci (C. psittaci) and to explore the effect of high-dose tigecycline on severe C psittaci.

Patients and Methods

We retrospectively analyzed the clinical characteristics, treatment, and outcomes of three progressive pneumonia patients caused by C. psittaci in our hospital in the past three years.

Results

All three patients showed high fever and progressive dyspnea, and all of them were finally diagnosed by bronchoalveolar lavage fluid (BALF) of metagenomic next-generation sequencing (mNGS). Case 1 rapidly developed into multilobar infiltration after raising a parrot with a normal appearance one week before. Respiratory failure occurred despite the use of moxifloxacin, requiring non-invasive ventilator-assisted ventilation. Case 2 developed discomfort one day after sightseeing in the forest park. Moxifloxacin was ineffective for her and she quickly developed respiratory failure, requiring invasive ventilator-assisted ventilation. Case 3 kept chickens and ducks at home. Respiratory failure and renal failure still occurred rapidly despite the use of doxycycline, requiring invasive ventilator-assisted ventilation and continuous renal replacement therapy (CRRT). After adjusting the antibiotic to high-dose tigecycline (100mg, I.V., q12h), all three patients were treated effectively and no side effects occurred.

Conclusion

C. psittaci pneumonia is one of the causes of progressive pneumonia. High-dose tigecycline is safe and effective for the treatment of severe C. psittaci.

Clinical Features of Dermatomyositis/Polymyositis with Anti-MDA5 Antibody Positivity

This paper aims to investigate the clinical and laboratory test characteristics of patients with anti-MDA5 antibody-positive PM/DM by analyzing the clinical characteristics, laboratory test results, and 1-year survival rate of patients with anti-MDA5 antibody-positive PM/DM in polymyositis (PM) and dermatomyositis (DM). To further investigate the impact of positive anti-MDA5 antibodies on the prognosis of PM/DM patients. According to the anti-MDA5 antibody test results, 18 cases with positive anti-MDA5 antibodies were in the positive group and 46 cases with negative anti-MDA5 antibodies were in the negative group. The clinical manifestations, laboratory tests, treatment protocols, and prognostic risk factors were collected for both groups. The chi-square test, Mann–Whitney method, Fisher test, t-test, Kaplan–Meier method, and Log-rank test were used for statistical analysis. Anti-MDA5 antibody positivity was more common in patients with DM/CADM. With no statistically significant differences in age and sex ratio between the two groups, The differences in erythrocyte sedimentation rate (ESR), ferritin (Fer), and creatine kinase (CK) levels in the positive group were statistically significant compared with the negative group. Clinically, the positive group was more prone to arthralgia, skin rash, and interstitial pneumonia.

Ground-glass opacity (GGO): a review of the differential diagnosis in the era of COVID-19

Thoracic imaging is fundamental in the diagnostic route of Coronavirus disease 2019 (COVID-19) especially in patients admitted to hospitals. In particular, chest computed tomography (CT) has a key role in identifying the typical features of the infection. Ground-glass opacities (GGO) are one of the main CT findings, but their presence is not specific for this viral pneumonia. In fact, GGO is a radiological sign of different pathologies with both acute and subacute/chronic clinical manifestations. In the evaluation of a subject with focal or diffuse GGO, the radiologist has to know the patient’s medical history to obtain a valid diagnostic hypothesis. The authors describe the various CT appearance of GGO, related to the onset of symptoms, focusing also on the ancillary signs that can help radiologist to obtain a correct and prompt diagnosis.