Pulmonary inflammatory pseudotumor due to Coxiella burnetii. Case report and literature review

Q Fever—A Neglected Zoonosis

Q fever remains a neglected zoonosis in many developing countries including Pakistan. The causing agent Coxiella (C.) burnetii is resistant to environmental factors (such as drying, heat and many disinfectants), resulting in a long-lasting infection risk for both human and animals. As the infection is usually asymptomatic, it mostly remains undiagnosed in animals until and unless adverse pregnancy outcomes occur in a herd. In humans, the infection leads to severe endocarditis and vascular infection in chronic cases. Limited data are available on molecular epidemiology and evolution of this pathogen, especially in ruminants. Genomic studies will help speculating outbreak relationships in this scenario. Likewise, pathogenesis of C. burnetii needs to be explored by molecular studies. Awareness programs and ensuring pasteurization of the dairy milk before human consumption would help preventing Q fever zoonosis.

Coxiellaceae in Ticks from Human, Domestic and Wild Hosts from Sardinia, Italy: High Diversity of Coxiella-like Endosymbionts

PURPOSE

Coxiella burnetii is known for its potential as veterinary and human bacterial pathogen. The bacteria have been described in ticks, but their role in transmission of Q fever in humans is considered low. Coxiella endosymbionts closely related to C. burnetii have been also isolated from an extensive range of tick species and evidence is growing that these endosymbionts could be linked to human bacteremia. The aim of this study was to get new information on the presence of Coxiella species in ticks infesting wild and domestic hosts in Sardinia, Italy.

METHODS

Here, 138 ticks collected from the study area were analyzed for the presence of C. burnetii and Coxiella-like bacteria by polymerase chain reaction (PCR), sequencing and philogenetic analyses using a set of primers targeting the 16S rRNA gene.

RESULTS

DNA of Coxiella species was detected in 69% of the total ticks examined. Based on phylogenetic analysis, the 16S rRNA Coxiella genotypes identified in this study grouped in strongly supported monophyletic clades with identified reference sequences of CLEs detected from Rhipicephalus, Dermacentor, Haemaphysalis and Ornithodoros species and with Coxiella burnetii strains isolated worldwide.

CONCLUSION

This study reports the molecular detection of a high diversity of Coxiella-like bacteria in Sardinian ticks and confirms also the presence of C. burnetii in tick species previously identified in the island. The role that Coxiella-like endosymbionts play in Sardinian ticks and in their vertebrate hosts needs to be explored further.

Recent Clinical and Preclinical Studies of Hydroxychloroquine on RNA Viruses and Chronic Diseases: A Systematic Review

The rapid spread of the new Coronavirus Disease 2019 (COVID-19) has actually become the newest challenge for the healthcare system since, to date, there is not an effective treatment. Among all drugs tested, Hydroxychloroquine (HCQ) has attracted significant attention. This systematic review aims to analyze preclinical and clinical studies on HCQ potential use in viral infection and chronic diseases. A systematic search of Scopus and PubMed databases was performed to identify clinical and preclinical studies on this argument; 2463 papers were identified and 133 studies were included. Regarding HCQ activity against COVID-19, it was noticed that despite the first data were promising, the latest outcomes highlighted the ineffectiveness of HCQ in the treatment of viral infection. Several trials have seen that HCQ administration did not improve severe illness and did not prevent the infection outbreak after virus exposure. By contrast, HCQ arises as a first-line treatment in managing autoimmune diseases such as rheumatoid arthritis, lupus erythematosus, and Sjögren syndrome. It also improves glucose and lipid homeostasis and reveals significant antibacterial activity.

Syphilitic Pulmonary Inflammatory Pseudotumor: A Diagnostic Challenge

A 46-year-old man presented with nonproductive cough and lower limb swelling. Chest radiograph showed a left lower lobe lung mass and multiple subpleural nodules. Other investigations revealed that he had nephrotic syndrome. Core biopsies of the left lower lobe lung mass showed features of inflammatory pseudotumor with endarteritis obliterans and a lymphoplasmacytic infiltrate. Immunohistochemical stain for Treponema pallidum was positive. Resolution of the lung mass and nephrotic syndrome was achieved after treatment with intramuscular benzathine benzylpenicillin. The differential diagnosis of pulmonary inflammatory pseudotumor, manifestations of pulmonary syphilis, and a literature review of secondary syphilis of the lung are discussed.

Acute Q fever pneumonia: high-resolution computed tomographic findings in six patients

METHODS:

We analyzed high-resolution CT (HRCT) findings from six male patients (mean age, 22.6 years) with confirmed diagnoses of acute Q fever. Two chest radiologists analyzed the images and reached decisions by consensus. All patients presented fever, myalgia, prostation, headache, and dry cough. They also had common epidemiologic factors (recent travel for military service, where they had contact with sheep and capybara). Diagnoses were confirmed by the detection of C. burnetii DNA in clinical samples by polymerase chain reaction.

RESULTS:

The predominant HRCT findings were areas of consolidation (100%) and nodules (66.6%) with halos of ground-glass opacity, predominantly with segmental and peripheral distributions. Lesions affected all lobes, and predominated in the left upper and lower lobes. Involvement of more than one lobe was observed in four patients. No pleural effusion or lymph node enlargement was found.

CONCLUSION:

The predominant HRCT findings in patients with acute Q fever pneumonia were bilateral, peripheral areas of consolidation and nodules with irregular contours and halos of ground-glass opacity.

ADVANCES IN KNOWLEDGE:

Acute Q fever should be included in the differential diagnosis of lesions with the halo sign on HRCT.

Clinical Features and Complications of Coxiella burnetii Infections From the French National Reference Center for Q Fever

IMPORTANCE

Q fever remains widespread throughout the world; the disease is serious and causes outbreaks and deaths when complications are not detected. The diagnosis of Q fever requires the demonstration of the presence of Coxiella burnetii and the identification of an organic lesion.

OBJECTIVE

To describe the hitherto neglected clinical characteristics of Q fever and identifying risk factors for complications and death.

DESIGN, SETTING, AND PARTICIPANTS

This prospective cohort study conducted from January 1, 1991, through December 31, 2016, included patients treated at the French National Reference Center for Q fever with serologic findings positive for C burnetii and clinical data consistent with C burnetii infection. Clinical data were prospectively collected by telephone. Patients with unavailable clinical data or an unidentified infectious focus were excluded.

MAIN OUTCOMES AND MEASURES

Q fever complications and mortality.

RESULTS

Of the 180 483 patients undergoing testing, 2918 had positive findings for C burnetii and 2434 (68.8% men) presented with clinical data consistent with a C burnetii infection. Mean (SD) age was 51.8 (17.4) years, and the ratio of men to women was 2.2. At the time of inclusion, 1806 patients presented with acute Q fever, including 138 with acute Q fever that progressed to persistent C burnetii infection, and 766 had persistent focalized C burnetii infection. Rare and hitherto neglected foci of infections included lymphadenitis (97 [4.0%]), acute Q fever endocarditis (50 [2.1%]), hemophagocytic syndrome (9 [0.4%]), and alithiasic cholecystitis (11 [0.4%]). Vascular infection (hazard ratio [HR], 3.1; 95% CI, 1.7-5.7; P < .001) and endocarditis (HR, 2.4; 95% CI, 1.1-5.1; P = .02) were associated with an increased risk of death. Independent indicators of lymphoma were lymphadenitis (HR, 77.4; 95% CI, 21.2-281.8; P < .001) and hemophagocytic syndrome (HR, 19.1; 95% CI, 3.4-108.6; P < .001). The presence of anticardiolipin antibodies during acute Q fever has been associated with several complications, including hepatitis, cholecystitis, endocarditis, thrombosis, hemophagocytic syndrome, meningitis, and progression to persistent endocarditis.

CONCLUSIONS AND RELEVANCE

Previously neglected foci of C burnetii infection include the lymphatic system (ie, bone marrow, lymphadenitis) with a risk of lymphoma. Cardiovascular infections were the main fatal complications, highlighting the importance of routine screening for valvular heart disease and vascular anomalies during acute Q fever. Routine screening for anticardiolopin antibodies during acute Q fever can help prevent complications. Positron emission tomographic scanning could be proposed for all patients with suspected persistent focused infection to rapidly diagnose vascular and lymphatic infections associated with death and lymphoma, respectively.

Pulmonary manifestations of Q fever: analysis of 38 patients

Background

Lung involvement in both acute and chronic Q fever is not well described with only a few reported cases of pseudotumor or pulmonary fibrosis in chronic Q fever. The aim of this study was to better understand the pulmonary manifestations of Q fever.

Methods

We conducted a retrospective cohort study of patients with diagnosis of Q fever at Mayo Clinic Rochester. A total of 69 patients were initially identified between 2001 and 2014. Thirty-eight patients were included in this study as 3 were pediatric patients, 20 did not meet serologic criteria for Q fever, and 8 did not have imaging available at time of initial diagnosis. Descriptive analysis was conducted using JMP software.

Results

The median age was 57 years [interquartile range (IQR) 43, 62], 84% from the Midwest, and 13% worked in an occupation involving animals. The most common presentation was fevers (61%). Respiratory symptoms, such as cough, were noted in only 4 patients (11%). Twelve patients (29%) had abnormal imaging studies attributed to Q fever. Three patients (25%) with acute Q fever had findings of consolidation, lymphadenopathy, pleural effusions, and nonspecific pulmonary nodules. Radiographic findings of chronic Q fever were seen in 9 patients (75%) and included consolidation, ground-glass opacities, pleural effusions, lymphadenopathy, pulmonary edema, and lung pseudotumor.

Conclusions

Our results demonstrate that pulmonary manifestations are uncommon in Q fever but include cough and consolidation for acute Q fever and radiographic findings of pulmonary edema with pleural effusions, consolidation, and pseudotumor in those with chronic Q fever.