Renal aspergillosis after liver transplantation: Clinical and imaging manifestations in two cases

Imaging Findings in Aspergillosis: From Head to Toe

Aspergillosis is a mycotic infection induced by airborne fungi that are ubiquitous. Inhalation of Aspergillus conidia results in transmission through the respiratory tract. The clinical presentation is dependent on organism and host specifics, with immunodeficiency, allergies, and preexisting pulmonary disease constituting the most important risk factors. In recent decades, the incidence of fungal infections has increased dramatically, due in part to the increased number of transplants and the pervasive use of chemotherapy and immunosuppressive drugs. The spectrum of clinical manifestations can range from an asymptomatic or mild infection to a swiftly progressive, life-threatening illness. Additionally, invasive infections can migrate to extrapulmonary sites, causing infections in distant organs. Recognition and familiarity with the various radiological findings in the appropriate clinical context are essential for patient management and the prompt initiation of life-saving treatment. We discuss the radiological characteristics of chronic and invasive pulmonary aspergillosis, as well as some of the typically unexpected extrapulmonary manifestations of disseminated disease.

Urinary Aspergillosis in a Patient with Systemic Lupus Erythematosus (SLE)

Aspergillosis is an opportunistic mycosis that generally affects the lungs. The fungus was cleared by the immune system of a healthy host. Extrapulmonary forms are very rare, and there are few reports of urinary aspergillosis. In this case report, we describe a 62-year-old woman with systemic lupus erythematosus (SLE) with complaints of fever and dysuria. The patient had recurrent episodes of urinary tract infection and several hospitalizations. A computed tomography revealed an amorphous mass in the left kidney and bladder. After partial resection of the material was referred for analysis, Aspergillus infection was suspected and confirmed by culture. Successful treatment with voriconazole was provided. Diagnosis of localized primary renal Aspergillus infection in a patient with SLE requires careful investigation due to its benign presentation and lack of associated systemic clinical features.

Infection as a Differential Diagnosis of Solid Retroperitoneal Masses: A Case Series and Review of the Literature

The differential diagnosis of retroperitoneal masses includes a variety of benign and malignant conditions, among which infections constitute a significant subgroup. Familiarity with these infectious pseudotumours could facilitate prompt diagnosis. In this report, we describe three patients with an infectious pseudotumour, which was clinically and radiologically highly suggestive of a neoplasm.

The first patient was a 62-year-old woman with a history of Richter syndrome, who seven months after allogeneic haematopoetic stem cell transplantation from an unrelated donor presented with a renal mass. A renal biopsy at that time revealed necrotic tissue. The patient displayed multiple relapses of Richter syndrome (for which she received also chimeric antigen receptor T-cell therapy salvage chemotherapy) and remissions of the lymphoma as well as an Aspergillus pneumonia for which she was treated with intravenous ambisome and afterwards oral posaconazole. Since the renal mass persisted and to exclude malignancy, nephrectomy was performed which revealed the presence of fungal hyphae.

The second patient was a 51-year-old man with a history of a low-grade non-muscle-invasive bladder urothelial carcinoma, who after Mycobacterium bovis Calmette-Guerin instillation presentedwith fever and a suspicious renal mass. A partial nephrectomy was performed. Intraoperative frozen section analysis and routine histology suggested a Mycobacterium bovis-associated lesion, which was confirmed by polymerase chain reaction (PCR) analysis.

The third patient was an 85-year-old man who presented with loss of appetite, fatigue, and significant weight loss (24 Kg in less than a year) as well as a travel history. The laboratory tests showed a low sodium and a high potassium level. CT scans revealed a solitary lesion in the right lung, a small liver lesion as well as bilateral adrenal lesions. A CT-guided biopsy revealed the presence of Histoplasma capsulatum, which was confirmed by PCR analysis. A retrospective review of all parameters indicates that all three patients presented with some risk factors, such as immunosuppression, travel, or clinical history that could raise the suspicion of infection in order to be included in the differential diagnosis, thus providing an additional tool for timely diagnosis.

A rare case of atypical ANCA-associated vasculitis without crescents overlapping with invasive pulmonary aspergillosis, successfully treated to remission with intravenous immunoglobulin therapy

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is life-threatening without treatment, but aggressive immunosuppression increases the risk of exacerbating a coexisting infection. Finding the balance between efficacy and safety of immunosuppression is challenging. We describe a 74-year-old man who was diagnosed with AAV following the aggravation of chronic pulmonary aspergillosis that required an aggressive antifungal agent. The laboratory data on admission demonstrated severe kidney failure requiring hemodialysis. Due to the active infection, we chose intravenous immunoglobulin (IVIg) as a low-risk initial treatment, which remarkably improved renal dysfunction (serum creatinine; 16.7 mg/dL-3.7 mg/dL) and systemic inflammation. Renal biopsy that was performed after renal recovery revealed atypical ANCA-associated nephritis without cellular crescents but with massive arteritis with multiple vascular sizes and diffuse interstitial inflammation. Despite these active AAV findings, adding plasma exchange therapy (PE) and low-dose steroids were sufficient to induce remission. The main pathogenesis of severe renal impairment was probably the reduction of blood flow, resulting from occlusions of small arteries by inflammatory cell infiltration and vascular endothelial injury due to AAV. Combination treatment with antifungal agents, IVIg, PE, and low-dose steroid treatment led to complete resolution of vasculitis. The specific histological findings and the good response to treatments suggest that pulmonary aspergillosis might trigger vasculitis through induction of ANCA antigen expression. IVIg could be an important option especially for cases of AAV associated with pulmonary aspergillosis.

Case of Renal Aspergillosis after Heart Transplant: Diagnosis and Treatment

Invasive aspergillosis (IA) is a severe complication after heart transplantation (HTx), with a high mortality rate. Invasive pulmonary aspergillosis (IPA) is the most common presentation. We herein describe a unique case of Renal aspergillosis (RAsp) diagnosed on month 10 post-HTx with no known risk factors for IPA in cardiac transplant recipients. The diagnosis of RAsp was made based on radiographic findings, renal biopsy, and tissue cultures. The patient initially received combined antifungal therapy (caspofungin and voriconazole) without radical or partial nephrectomy, followed by voriconazole maintenance monotherapy with favorable clinical outcomes.

Renal aspergillosis in a liver transplant patient: A case report and review of literature

BACKGROUND

Aspergillosis is a frequent invasive fungal infection in liver recipients (affecting 1%-9.2% of all patients), second only to candidiasis. Significant risk factors for invasive aspergillosis in liver recipients include corticosteroid therapy, neutropenia, T-cell dysfunction, renal failure and requirement for renal replacement therapy. Aspergillus infection usually affects the lungs of liver recipients, with hematogenous dissemination occurring in 50%-60% of cases. Renal involvement is rare and is considered to occur in 0.4% of all cases of invasive aspergillosis.

CASE SUMMARY

This paper describes a case of a liver recipient presenting with a newly formed renal mass a year after liver transplantation. The patient underwent liver transplantation due to alcoholic liver cirrhosis, with preoperative corticosteroid therapy and postoperative immunosuppressants (tacrolimus and mycophenolate mofetil). His 1-year follow-up was uneventful, with a satisfying graft function and lack of any symptoms. During a routine follow-up abdominal ultrasound, he was diagnosed with a renal tumor. The renal imaging findings were inconclusive (with a differential diagnosis to renal cell carcinoma), while the computed tomography (CT) of the chest showed scar tissue in the lungs suggestive of previous inflammation. The patient underwent radical nephrectomy, with histopathological analysis showing renal aspergilloma, yielding postoperative treatment with voriconazole. His follow up was uneventful, and the chest CT did not show any change in pulmonary lesions. This case illustrates the possibility of aspergillosis affecting the lungs of liver recipients, subsequently affecting the kidney and forming an aspergilloma.

CONCLUSION

Clinicians should be aware of aspergilloma mimicking solid organ tumors in organ recipients.

Multimodality Imaging Findings of a Renal Aspergilloma

BACKGROUND

Renal aspergillosis is a rare infection that usually occurs in persons with a predisposition for this condition. Its differential diagnosis includes primary and metastatic renal malignancies, pyelonephritis and secondary abscess formation, granulomatous disorders, and renal infarction. We aim to stress the role of multimodality imaging and percutaneous biopsy in the diagnosis of this condition.

CASE REPORT

We present diffusion weighted imaging (DWI) and positron emission tomography-computed tomography (PET-CT) findings in addition to conventional imaging modalities in a 55-year-old man with secondary renal aspergilloma.

CONCLUSION

Radiological imaging methods are an integral part of diagnostic workup for renal aspergillosis. A definitive diagnosis is made by histopathological and/or microbiological examination of the material obtained via percutaneous biopsy under guidance of imaging methods.