Imaging spectrum of common and rare infections affecting the lower genitourinary tract

In this review, we will discuss the imaging findings of common as well as uncommon lower genitourinary tract infections. For both clinicians and radiologists, it is imperative to understand etiopathogenesis, epidemiological information, clinical presentation, imaging findings and management options of such conditions. Knowledge of salient imaging features of these infections is of utmost importance because prompt recognition enables appropriate management.

Imaging Manifestations of Genitourinary Tuberculosis

The genitourinary region is one of the most common sites of extrapulmonary tuberculosis (TB) involvement. The imaging features of genitourinary TB are protean and can mimic other entities, including malignancy, and pose a diagnostic dilemma. Hematogenous seeding and lymphatic spread of mycobacteria from pulmonary, tonsillar, and nodal TB are implicated in the pathogenesis of genitourinary TB. In addition, contiguous extension from the urinary tract and sexual transmission are described as sources of genital TB. Genitourinary TB can be indolent and results in nonspecific signs and symptoms; thus, imaging has a vital role in the working diagnosis for these cases. Classic uroradiologic signs of genitourinary TB are primarily described from the era of intravenous urography and conventional radiography. Now, CT, CT urography, MRI, and US are used in the diagnosis and management. Familiarity with the imaging features of genitourinary TB may help guide the diagnosis and, in turn, lead to timely management. US has a vital role in the evaluation of scrotal and female genital TB. MRI offers superior soft-tissue contrast resolution and excellent depiction of anatomic detail. The various imaging manifestations of genitourinary TB are highlighted. ^©RSNA, 2021.

CT Urography Findings of Upper Urinary Tract Carcinoma and Its Mimickers: A Pictorial Review

Urothelial carcinoma (UC) is the fourth most frequent tumor in Western countries and upper tract urothelial carcinoma (UTUC), affecting pyelocaliceal cavities and ureter, accounts for 5-10% of all UCs. Computed tomography urography (CTU) is now considered the imaging modality of choice for diagnosis and staging of UTUC, guiding disease management. Although its specificity is very high, both benign and malignant diseases could mimic UTUCs and therefore have to be well-known to avoid misdiagnosis. We describe CTU findings of upper urinary tract carcinoma, features that influence disease management, and possible differential diagnosis.

Multimodality Imaging of Genitourinary Tuberculosis

Tuberculosis (TB) prevalence has increased over the past few decades, especially in the developing world. The genitourinary tract is the most common extra-pulmonary location of TB. Symptoms of genitourinary TB are often vague. Diagnosis of genitourinary TB requires a high level of clinical suspicion. Healthcare providers must be familiar with genitourinary TB imaging features on different imaging modalities and how to correlate these findings with urine studies and histologic analysis to definitively diagnose genitourinary TB.

Imaging of Renal Infections and Inflammatory Disease

Acute pyelonephritis is a bacterial infection of the renal parenchyma and collecting system. Diagnosis is based on clinical findings of fever, flank pain, and urinary tract infection. Computed tomography findings include renal enlargement with wedge-shaped heterogeneous areas of decreased enhancement, known as a "striated nephrogram." Imaging is primarily used to diagnose complications such as emphysematous pyelonephritis, renal abscess, and pyonephrosis. Chronic pyelonephritis can have varying appearances on imaging ranging from xanthogranulomatous pyelonephritis or, in extreme cases, renal replacement lipomatosis.

Multidetector computed tomography has replaced conventional intravenous excretory urography in imaging of the kidneys: A scoping review of multidetector computed tomography findings in renal tuberculosis

BACKGROUND

Tuberculosis (TB) is a worldwide infectious disease burden, especially in non-developed countries, with increased morbidity and mortality among human immunodeficiency virus (HIV)-infected patients. Extrapulmonary TB is rare and renal TB is one of the commonest manifestations. The end result of renal TB is end-stage renal disease; however, this can be avoided if the diagnosis is made early. The diagnosis of renal TB is challenging because of the non-specific presentation and low sensitivity of clinical tests. Although the sequel of TB infection in the kidney causes varying manifestations depending on the stage of the disease, multidetector computed tomography (MDCT) is capable of demonstrating early findings. We performed a 20-year scoping review of MDCT findings in renal TB to promote awareness.

AIM

To identify specific MDCT imaging characteristics of renal TB, promote early diagnosis and increase awareness of the typical imaging features.

METHODS AND MATERIAL

We searched published and unpublished literature from 1997 to 2017 using a combination of search terms on electronic databases. We followed the Joanna Briggs Institute guidelines.

RESULTS

A total of 150 articles were identified, of which 145 were found through electronic search engines and 5 were obtained from grey literature. Seventy-nine articles that fulfilled our inclusion criteria were reviewed. These included original research, case reports, literature review, organisational reports and grey literature.

CONCLUSION

Multidetector computed tomography can reproduce images comparable with intravenous excretory urography; together with advantages of being able to better assess the renal parenchyma and surrounding spaces, it is important in suggesting the diagnosis of renal TB and clinicians should consider including MDCT when investigating patients with recurrent urinary tract infection not responding to usual antimicrobial therapy.

Multidetector CT urography in urogenital tuberculosis: use of reformatted images for the assessment of the radiological findings. A pictorial essay

Urogenital tuberculosis (UGTB) is the most common form of extrapulmonary TB and is responsible for a destructive inflammation of the renal parenchyma and urinary tract often leading to the loss of kidney function. For these reasons, the early diagnosis of this disease, once considered disappeared in developed countries, is very important to establish a prompt and efficient treatment. However, the subtle and non-specific symptoms, often represented by recurrent and persistent lower urinary tract symptoms, can confound and delay the diagnosis. Therefore, an adequate and comprehensive imaging study is necessary in patients with persistent urinary tract infections not responding to the antibiotics and can suggest the hypothesis although bacteriological and/or histologic analysis is required for a definitive diagnosis. In the past years, intravenous urography (IVU) has allowed a comprehensive study of the urinary excretory tract, promoting the knowledge of the radiological findings of this disease. Nowadays, computed tomography urography (CTU), with the implementation of multidetector (MD) technology, has replaced IVU in all its indications; the MDCTU improves the assessment of renal and urinary tract lesions using reformatted images [such as multiplanar reconstruction (MPR) and maximum intensity projection (MIP)]. Therefore, our paper aims to provide a guide for radiologist for searching the classic signs of UGTB on MDCTU, encouraging the use of the MPR and MIP reformatted images.