Omadacycline for the Treatment of Severe Chlamydia psittaci Pneumonia Complicated with Guillain-Barre Syndrome

Background

Chlamydia psittaci (C. psittaci) is a pathogen that is seldom implicated in community-acquired pneumonia and is rarely linked to severe pneumonia. Reports of severe C. psittaci pneumonia accompanied by Guillain-Barre syndrome (GBS) are scarce. Tetracyclines are the preferred therapeutic approach for psittacosis. Omadacycline, a novel tetracycline, demonstrates strong antibacterial efficacy against typical bacteria and atypical pathogens, including C. psittaci. However, its application in the treatment of psittacosis pneumonia remains constrained.

Case Presentation

A 77-year-old female patient was admitted to the hospital presenting with symptoms of fever, low back pain, and headache. The diagnosis of C. psittaci was established through the utilization of metagenomic next-generation sequencing (mNGS). Initial administration of moxifloxacin, meropenem, piperacillin-tazobactam, and doxycycline proved to be ineffective. Subsequent omadacycline leaded to the successful resolution of fever and dyspnea. However, after the endotracheal tube was removed, the patient experienced a rapid decline in symmetrical limb strength, leading to a diagnosis of GBS based on clinical manifestations, cerebrospinal fluid analysis, and electromyography. Following a 5-day course of immunoglobulin therapy and nutritional nerve treatment, the patient's condition ameliorated, culminating in an uncomplicated discharge.

Conclusion

This case provides evidence supporting the potential use of omadacycline as a therapeutic option for the treatment of severe C. psittaci pneumonia. The utilization of mNGS technology is of paramount importance in the prompt identification of uncommon pathogens, including C. psittaci. Nevertheless, the occurrence of GBS should be taken into consideration when C. psittaci pneumonia is accompanied by symmetrical limb weakness. These findings have important implications for the diagnosis, treatment, and management of patients with C. psittaci pneumonia.

Acute abdominal pain as the first symptom of Chlamydia psittaci pneumonia complicated by acute pancreatitis: a case report

Background

Chlamydia psittaci infections primarily cause damage to the lungs but may also affect the cardiovascular system, gastrointestinal tract, liver, kidney, and brain, resulting in a variety of extrapulmonary complications. However, reports regarding C. psittaci infection-associated pancreatitis are rare. In this report, a patient with C. psittaci pneumonia complicated by acute pancreatitis is presented.

Case description

The patient presented with acute upper abdominal pain and developed severe pyrexia and dyspnoea one day later. A chest computed tomography image revealed patchy consolidation in the left lung. The disease progressed rapidly, and the patient exhibited liver and kidney damage and type 1 respiratory failure within a short period of time. Metagenomic next-generation sequencing of alveolar lavage fluid revealed the presence of C. psittaci. The patient was administered doxycycline and moxifloxacin, after which the patient's abdominal pain and lung infection significantly resolved.

Conclusion

This case report demonstrates that extrapulmonary C. psittaci infections due to secondary acute pancreatitis can manifest as abdominal pain, although the exact mechanisms of C. psittaci caused by acute pancreatitis remain unclear. Timely diagnoses and treatments of such infections are necessary to achieve favorable clinical outcomes.

Clinical features and outcome of eight patients with Chlamydia psittaci pneumonia diagnosed by targeted next generation sequencing

INTRODUCTION

The clinical symptoms of Chlamydia psittaci pneumonia are still poorly understood. This study was designed to summarize the clinical features and outcome of eight C. psittaci pneumonia patients diagnosed by targeted next generation sequencing (tNGS).

METHODS

We included eight C. psittaci pneumonia patients admitted to our hospital from January 2021 to July 2022. The tNGS was performed to the samples collected from bronchoalveolar lavage fluid of each patient. Their clinical data were analysed, including baseline features, clinical symptoms, chest radiographic findings and laboratory examinations.

RESULTS

The tNGS sequence number for C. psittaci was in a range of 10 to 1722. The radiographic characteristics were mainly featured by patchy consolidation shadows, ground-glass density shadows, air bronchogram and slight pleural effusion. Within 1-3 days after hospitalization, most patients showed increased neutrophil ratio, C-reactive protein and erythrocyte sedimentation rate, and decreased lymphocyte count, total protein, albumin and prealbumin. Some patients showed increased glutamic-pyruvic transaminase, glutamic-oxaloacetic transaminase and lactate dehydrogenase levels. Three critically ill patients showed increased creatine kinase, creatine kinase isoenzyme and high-sensitivity troponin T (hs-TnT) levels.

CONCLUSIONS

A poultry or bird contact history, typical flu-like symptoms, patchy consolidation, ground-glass density shadow and air bronchogram may contribute to the diagnosis and treatment of C. psittaci pneumonia. Increase in creatine kinase, creatine kinase isoenzyme and hs-TnT may indicate a severe condition. Moxifloxacin and minocycline were effective in the management of C. psittaci pneumonia.

Chlamydia psittaci pneumonia in Wuxi, China: retrospective analysis of 55 cases and predictors of severe disease

Purpose

More and more patients with community-acquired pneumonia have been detected with Chlamydia psittaci (C. psittaci) infected using metagenomic next-generation sequencing (mNGS). Previously, this was unheard of, and several patients presented with severe pneumonia and even required ECMO. We aimed to clarify the clinical characteristics of C. psittaci pneumonia and find out if there are any possible predictors of severe C. psittaci pneumonia.

Methods

In this retrospective study, we included all confirmed cases of C. psittaci pneumonia in Wuxi. Epidemiological, clinical, and radiological features, as well as laboratory data, were collected and analyzed.

Results

We enrolled 55 patients with C. psittaci pneumonia, with 30 (54.5%) having a history of exposure to birds or their internal organs. 50 (90.9%) patients were diagnosed by mNGS. Patients with C. psittaci pneumonia had many complications, among which, that deserve sufficient attention from clinicians were vascular embolic events (3, 5.5%). High fever was the most common clinical manifestation (41, 74.5%). The majority of patients had a significant increase in neutrophils ratio, neutrophils to lymphocytes ratio (NLR), rapid c-reactive protein, creatine kinase (CK), and lactate dehydrogenase (LDH), as well as a decrease in lymphocytes ratio, albumin, serum sodium, serum potassium, and serum phosphorus. Chest computed tomography scans revealed unilateral pneumonia (70.9%), consolidation (87.3%), air bronchogram (76.4%), and ground-glass opacity (69.1%). The neutrophil ratio, NLR, LDH, and CK were all factors that could identify severe pneumonia. Both AUCs exceeded 0.8; the respective 95% CIs were 0.715-0.944, 0.710-0.963, 0.677-0.937, and 0.718-0.950; all p < 0.05 (0.01, 0.001, 0.007, 0.007 respectively). The ORs were 10.057, 9.750, 10.057, and 9.667, respectively; the 95% CIs were 2.643-38.276, 2.339-40.649, and 2.643-38.276, respectively; all p-values were less than 0.05 (0.001, 0.002, 0.001, 0.001 respectively).

Conclusion

C. psittaci pneumonia is a very complex disease that changes all the time. Some patients showed severe pneumonia. Patients will have a poor prognosis if they are not treated promptly and effectively. We discovered that many clinical indicators were typical. Meanwhile, significant increases in neutrophil ratio, NLR, LDH, and CK predicted severe pneumonia. Timely detection of mNGS provided substantial help for clinical diagnosis and early treatment.

Comparison of clinical, laboratory and radiological characteristics between Chlamydia psittaci and adenovirus pneumonias: a multicenter retrospective study

OBJECTIVES

Pneumonia caused by Chlamydia psittaci is a significant global public health issue. Symptom onset and laboratory characteristics may be confused with those of other respiratory viral infections, including adenovirus pneumonia. We aimed to determine differences in clinical presentations and establish a simple nomogram to differentiate C. psittaci and adenovirus pneumonias.

METHODS

We conducted a multicenter retrospective study in 10 tertiary general hospitals to compare patients with either C. psittaci (n = 78) or adenovirus (n = 102) pneumonia. A multivariable logistic regression model was used to identify risk factors of C. psittaci pneumonia that were used to establish a nomogram.

RESULTS

C. psittaci and adenovirus pneumonia showed certain similar clinical symptoms, including fever, dyspnea, and fatigue, but differed in other characteristics. The multivariate logistic regression showed that age, sex, nervous system symptoms, lymphocyte count, C-reactive protein level, and bilateral lung lesions were risk factors for C. psittaci pneumonia. After incorporating these six factors, the established nomogram achieved a good concordance value (0.949 [95% CI 0.917-0.982]) in differentiating the types of pneumonia, with well-fitting calibration curves.

CONCLUSION

Despite having similar clinical features, the variables of age, sex, nervous system symptoms, lymphocytes, C-reactive protein levels, and bilateral lung lesions were combined into a clinically useful nomogram for the rapid and early differentiation of C. psittaci pneumonia from adenovirus pneumonia. This nomogram may help improve treatments and clinical outcomes.

Tigecycline in the treatment of severe pneumonia caused by Chlamydia psittaci: A case report and literature review

Psittacosis is a zoonotic disease caused by Chlamydia psittaci. Systemic infections are mainly transmitted through the respiratory tract. The most common related disease is human atypical pneumonia, which is a rare pathogen of community-acquired pneumonia. Due to the difficulty of diagnosis, there have been few reports of C. psittaci pneumonia in the past. In recent years, with the widespread application of metagenomic next-generation sequencing (mNGS), the number of reported cases of C. psittaci has increased year by year. However, at present, most hospitals have little understanding of C. psittaci, especially for severe patients, and lack experience in diagnosis and treatment. Herein, we report the case of a 71-year-old woman with severe pneumonia that caused by C. psittaci. This patient was diagnosed through mNGS and was treated with tigecycline successfully. The level of IL-6 in the BALF was significantly increased. We discontinued tigecycline after mNGS of the blood was negative. In this review, we analyzed 53 cases to summarize the etiology, clinical manifestations, diagnosis and treatment strategies of severe C. psittaci pneumonia and hope to raise clinicians' awareness of this disease.

Clinical Characteristics of Chlamydia psittaci Pneumonia Infection in Central South China

Introduction

Chlamydia psittaci pneumonia has been a global public health hotspot in recent years. Although some scattered cases of C. psittaci pneumonia have been reported, there is a lack of large case studies worldwide.

Methods

In this multicenter, observational study, we recruited all consecutive patients with confirmed C. psittaci pneumonia from October 4, 2018, to October 23, 2020, in nine tertiary general hospitals in Central-South China. Epidemiologic and clinical data from patients’ electronic medical records were collected and analyzed.

Results

One hundred and sixteen patients with C. psittaci pneumonia were included in the study. The mean age was 59.7 years. Fever (96.6%) and cough (65.5%) were the most common clinical symptoms. Most patients presented with an increase in the proportion of neutrophils, neutrophil to lymphocyte ratio, LDH, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) and a significant decrease in lymphocytes. The main CT lung findings were consolidation (81%) and pleural effusion (35.3%), and bilateral lung consolidation was mainly found in severe patients. Chlamydia psittaci DNA was detected in BALF (bronchoalveolar lavage fluid) or blood samples by metagenomic next-generation sequencing (mNGS) in all patients. Use of quinolone was associated with shorter length of hospital stay and fever duration after antibiotic use. Multivariate logistic regression analysis indicated that respiratory support was associated with both severe pneumonia and in-hospital death.

Conclusions

The clinical phenotype of C. psittaci pneumonia is complex and variable. mNGS is helpful in the diagnosis and treatment of C. psittaci pneumonia, and early treatment with quinolone may benefit patients.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40121-022-00662-4.

Application of metagenomic next-generation sequencing (mNGS) combined with rapid on-site cytological evaluation (ROSCE) for the diagnosis of Chlamydia psittaci pneumonia

We evaluated the application of metagenomic next-generation sequencing (mNGS) combined with rapid on-site cytological evaluation (ROSCE) in the diagnosis of Chlamydia psittaci pneumonia, to provide a basis for an accurate diagnosis. Clinical data from three patients with C. psittaci pneumonia diagnosed by the combination of mNGS and ROSCE from June 2019 to June 2020 in the Department of Respiratory and Critical Care Medicine of Tianjin Medical University General Hospital were reviewed. Three patients with community-acquired pneumonia failed to respond to the initial treatment, and were finally diagnosed by bronchoscopic lung biopsy and alveolar lavage fluid (BALF) mNGS. According to the ROSCE cytologic characteristics, the scope of the lesions was narrowed to inflammatory lesions excluding tumor and other non-infectious lesions. Subsequently, mNGS results confirmed that the three patients were infected by C. psittaci, sequence numbers 2066, 126, and 1077, respectively. Two patients developed severe pneumonia and required organ function support. The other patient had recurrent high fever and severe headache, which significantly complicated clinical diagnosis and treatment. Eventually, the treatment plan was adjusted according to the mNGS results, resulting in gradual improvement of symptoms and satisfactory prognosis. mNGS combined with ROSCE is effective for the accurate diagnosis and treatment of C. psittaci pneumonia, having significant advantages in comparison with other detection methods, particularly in the cases of rare pathogens, mixed pathogen infections, and immunodeficient patients.