Progressive and nonresolving 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.

Application of Transthoracic Shear Wave Elastography in Evaluating Subpleural Pulmonary Lesions

AIM

The objective of this research was to investigate the feasibility of transthoracic shear wave elastography in the differentiation of subpleural masses.

METHODS

Between December 2019 and November 2020,82 consecutive patients with radiographic evidence (including chest X ray and thoracic computed tomography CT) of single subpleural lesion enrolled in this research. The Young's modulus E (including E_mean and E_max) of each lesion was detected, and the Young's modulus E of malignant lesions were compared with those of benign ones. We made diagnoses according to the results of pathology or standard clinical course for at least 3 months. Receiver operating characteristic (ROC) analysis was plotted to determine the cut-off point by maximizing the Youden index.

RESULTS

The E_mean and E_max of the benign and malignant group was 34.68 ± 12.12 kPa vs. 53.82 ± 11.95 kPa (p < 0.001), 57.77 ± 14.45 kPa vs. 76.62 ± 17.04 kPa (p < 0.001). The ROC of E_mean showed that when the cut-off point was 43.8 kPa, the Youden index (0.53) for distinguishing benign and malignant tumors was the largest (sensitivity 80.4 %, specificity 72.2 %, AUC = 0.848, p < 0.0001). When the cut-off point recommended by E_max ROC was 73.5 kPa, the Youden index (0.44) for distinguishing benign and malignant tumors was the largest (sensitivity 76.1 %, specificity 66.7 %, AUC = 0.780, p < 0.0001).

CONCLUSIONS

This study demonstrated that we can employ transthoracic shear wave elastography as a valuable instrument in differentiating benign subpleural lesions from malign ones.

Detection of Viruses by Multiplex Real-Time Polymerase Chain Reaction in Bronchoalveolar Lavage Fluid of Patients with Nonresponding Community-Acquired Pneumonia

Background

Nonresponding pneumonia is responsible for the most mortality of community-acquired pneumonia (CAP). However, thus far, it is not clear whether viral infection plays an important role in the etiology of nonresponding CAP and whether there is a significant difference in the clinical characteristics between viral and nonviral nonresponding CAP.

Methods

From 2016 to 2019, nonresponding CAP patients were retrospectively enrolled in our study. All patients received bronchoalveolar lavage (BAL) and virus detection in BAL fluid by multiplex real-time polymerase chain reaction (PCR), and clinical, laboratory, and radiographic data were collected.

Results

A total of 43 patients were included. The median age was 62 years, and 65.1% of patients were male. Overall, 20 patients (46.5%) were identified with viral infection. Of these viruses, influenza virus (n = 8) and adenovirus (n = 7) were more frequently detected, and others included herpes simplex virus, human enterovirus, cytomegalovirus, human coronavirus 229E, rhinovirus, and parainfluenza virus. Compared with nonviral nonresponding CAP, only ground-glass opacity combined with consolidation was a more common imaging manifestation in viral nonresponding CAP. However, no obvious differences were found in clinical and laboratory findings between the presence and the absence of viral infections.

Conclusions

Viral infections were particularly frequent in adults with nonresponding CAP. The ground-glass opacity combined with consolidation was a specific imaging manifestation for viral nonresponding CAP, while the clinical and laboratory data showed no obvious differences between viral and nonviral nonresponding CAP.