Unrecognized pre-transplant disseminated Coxiella burnetti infection diagnosed in a post-transplant heart-kidney recipient

A Rare Q-Fever Infection Diagnosed Using Metagenomic Next-Generation Sequencing in Liver Transplantation Patient: A Case Report and Literature Review

Q fever is a zoonotic disease caused by the Gram-negative bacterium Coxiella burnetii, typically transmitted through exposure to infected animal secretions. As the clinical signs of Q-fever are largely non-specific in humans, a definitive diagnosis can often be overlooked, particularly when physicians fail to consider C. burnetii on the list of differentials. This case report describes Q-fever in a male patient who had previously undergone orthotopic liver transplantation. The patient had a sudden onset of fever and received the anti-infective moxifloxacin which proved ineffective. Despite the comprehensive laboratory tests and CT imaging that were performed, the etiology remained undetermined. The patient's blood was subjected to metagenomic next-generation sequencing (mNGS), which identified C. burnetii, after which the patient was treated with doxycycline and recovered well. Eight literature articles on Q fever infection in solid organ transplant recipients were reviewed. To our knowledge, this is the first case of Q fever identified by mNGS in an organ transplantation patient. The case underscores the potential of mNGS has in aiding the rapid detection of rare pathogens in immunocompromised patients.

Management options of valvular heart diseases after heart transplantation: A scoping review

Background

This study aimed to outline the valvular changes following heart transplantation and describe the management options to address these conditions.

Methods

A literature search using EMBASE, MEDLINE, and PubMed databases was performed in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines in this study. Clinical studies involving patients who had their first heart transplant and articles that mentioned management for valvular heart disease were included. Treatment options were grouped into four categories: cardiac surgery other than retransplant and valve surgery, valve replacement and repairs, nonsurgical interventions, and conservative management.

Results

Nine hundred and three (6.56%) patients out of 13,757 patients (10,529 males, 3,228 females; mean age: 60.3±10.4 years; range, 20 to 83 years) undergoing heart transplantation were identified with valvular disease affecting one or more valves. The mean interval between the transplant and the diagnosis of valve disease was 11.31±6.95 years. The most common valvular heart disease was tricuspid regurgitation, with 796 (94.09%) occurrences, followed by mitral regurgitation (n=22, 2.6%), aortic regurgitation (n=14, 1.65%), aortic stenosis (n=11, 1.3%), and mitral stenosis (n=3, 0.35%). Additionally, the number of surgical valve replacement and repairs (n=89) was higher than nonsurgical interventions (n=20).

Conclusion

Acquired valvular heart diseases after cardiac transplantation are an infrequent clinical presentation that can cause valvular changes in the recipient. According to the extracted data, there is no sole superior management option, and more research is needed in this area.

Infective endocarditis following heart transplantation: A systematic review

PURPOSE

Infective endocarditis (IE) is a rare but potentially fatal complication following heart transplantation (HTx). There is a lack of literature regarding the patterns and clinical course of IE development following HTx. We sought to pool the existing data in regards to defining characteristics, management options, and outcomes of IE following HTx.

METHODS

An electronic search of Cochrane Central Register of Controlled Trials, Cumulative Index to Nursing and Allied Health Literature, Ovid Medline, and the Scopus databases were performed to identify all articles in the English literature that report IE following HTx in adult patients. Patient-level data were extracted and analyzed.

RESULTS

Systematic search yielded 57 patients from 32 articles. Median patient age was 52 [IQR 43, 59] and 75% of patients (43/57) were male. Median time to IE presentation post-HTx was 8.4 [IQR 3.0, 35.8] months. IE of the mitral valve was observed in 36.8% (21/57) of patients, followed by mural IE in 24.6% (14/57), and tricuspid valve IE in 21.1% (12/57). The most common organisms were Staphylococcus aureus in 26.3% (15/57), Aspergillus fumigatus in 19.3% (11/57), Enterococcus faecalis in 12.3% (7/57), and an undetermined or unspecified organism in 14.0% (8/57) patients. Overall case fatality was 44.6% (25/56). Fungal IE was associated with a significantly higher case fatality 75.0% (9/12) than that of bacterial IE 36.1% (13/36) (p = 0.02). Surgical management of post-HTx IE was observed in 35.1% (20/57) of patients. This included valve surgery for 70.0% (14/20), including the mitral valve in 50.0% (7/14), aortic valve in 35.7% (5/14), and the tricuspid valve in 14.3% (2/14) of patients.

CONCLUSION

In addition to bacterial organisms, fungi also represent a frequent cause of IE in post-HTx patients. Overall HTx patient survival in the setting of IE is poor and may be worse if caused by A. fumigatus.

Utility of positron emission tomography imaging in the diagnosis of chronic Q fever: A Systematic Review

Chronic Q fever is a diagnostic challenge. Diagnosis relies on serology and/or the detection of DNA from blood or tissue samples. PET-CT identifies tissues with increased glucose metabolism, thus identifying foci of inflammation. Our aim was to review the existing literature on the use of PET-CT to help diagnose chronic Q fever. A literature search was conducted in PubMed and Google Scholar to ascertain publications that included the terms 'Positron Emission Tomography' and 'PET CT' in combination with subheadings 'chronic Q fever' and 'Coxiella burnetii' within the search. To broaden our search retrieval, we used the terms 'chronic Q fever' and 'PET-CT'. Published literature up to 16^th April 2020 was included. 274 articles were initially identified. Post-exclusion criteria, 46 articles were included. Amongst case reports and series, the most frequent focus of infection was vascular, followed by musculoskeletal then cardiac. 79.5% of patients had a focus detected with 55.3% of these having proven infected prosthetic devices. Amongst the retrospective and prospective studies, a total of 394 positive sites of foci were identified with 186 negative cases. Some had follow-up scans (53), with 75.5% showing improvement or resolution. Average timeframe for documented radiological resolution post-initiating treatment was 8.86 months. PET-CT is a useful tool in the management of chronic Q fever. Knowledge of a precise focus enables for directed surgical management helping reduce microbial burden, preventing future complications. Radiological resolution of infection can give clinicians reassurance on whether antimicrobial therapy can be ceased earlier, potentially limiting side effects.

FDG PET/CT for Detection of Infectious Complications Following Solid Organ Transplantation

Infectious complications after solid organ transplantation (SOT) are often more severe and remain a diagnostic challenge due to vague and atypical clinical presentations. Diagnostic performance of conventional diagnostic tools is frequently inadequate which may lead to delayed diagnosis with the risk of poorer outcomes. This literature review aimed to investigate the current evidence on the use of ¹⁸F-fluoro-deoxy-glucose (FDG) Positron Emission Tomography (PET)/computer tomography (CT) in infectious complications after SOT. Based on search in PubMed, Medline, and Cochrane databases, 13 articles and 46 case reports were included. For inclusion, articles were to include data on patients with infectious complications after SOT, and where FDG PET/CT was part of the work-up. Final searches were conducted on 02 September 2020. Overall, in the absence of initial diagnostic clues, FDG PET/CT should be considered as the imaging technique of choice as it may guide further investigations and eventually reveal the diagnosis in most of the patients. However, the available literature of the role of FDG PET/CT in SOT recipients with infectious complications is scarce and well-designed prospective studies including control groups are warranted to establish the role of FDG PET/C/ in SOT recipients. The main drawback of FDG PET/CT is the lack of ability to differentiate between cancer and infectious diseases which are both highly prevalent in this patient group. Accordingly, the main reasons for "false" results of FDG PET/CT is the misdiagnosis of cancer in benign inflammatory or infectious processes, information which nonetheless can be useful.

Severe acute Q fever pneumonia complicated by presumed persistent localized Q fever endocarditis in a renal transplant recipient: A case report and review of the literature

Q fever in solid organ transplant (SOT) recipients is rarely described in the medical literature. We present a case of severe acute Q fever pneumonia that evolved into persistent localized Q fever endocarditis in a renal transplant recipient.

Glomerulonephritis triggered by chronical aortic graft infection in a male with Loeys-Dietz syndrome: A case report

RATIONALE

Glomerulonephritis triggered by a chronically infected graft is increasingly identified because of widely used implanted device. Removal of the aortic graft and sustained antibiotic therapy is the usual approach to maximize the chance of renal recovery, but as this case shows graft removal is not always possible.

PATIENT CONCERNS

A 35-year-old man with intractable and recurrent fever had acute renal failure in sustained antibiotic therapy.

DIAGNOSES

Renal biopsy suggested crescentic glomerulonephritis. fluorodeoxyglucose/positron emission tomography-computed tomography showed increased metabolic activity at the site of aortic graft, reminding that chronic infection of an implanted graft can lead to severe glomerulonephritis. TGFBR2 c.1133G>T mutation was observed in mutation analysis, which was reported to be associated with Loeys-Dietz syndrome.

INTERVENTIONS

Although infection was properly controlled with appropriate antimicrobial treatment, his renal dysfunction did not improve. A short-term inclusion of low-dose corticosteroid significantly benefit without introducing harm.

OUTCOMES

He partly recovered from renal injury.

LESSONS

In patients with glomerulonephritis triggered by a long-duration infection, low-dose corticosteroid therapy may be considered when renal dysfunction secondary to nephritis does not improve after appropriate antimicrobial treatment.

Unusual presentation of Q fever in a kidney-pancreas transplant recipient

Q fever is uncommon in solid organ transplant (SOT) recipients. We describe a case of granulomatous lung disease as an unusual presentation of chronic Q fever in a kidney-pancreas transplant recipient.