Atypical small acinar proliferations (ASAP) are premalignant lesions of the prostate, which can be found in as many as 5% of prostate biopsies. They are suspicious glands without adequate histologic atypia to establish a definitive diagnosis of prostate cancer. Some studies showed that there is ...
Autosomal dominant polycystic kidney disease (ADPKD), also sometimes more vaguely referred to as "adult polycystic kidney disease", is as the name would suggest, a hereditary form of adult cystic renal disease.
Autosomal dominant polycystic kidney disease is one of the most commo...
Azoospermia refers to complete absence of sperm in the semen. It accounts for 5-10% of male infertility 1.
It can be obstructive or non-obstructive, e.g. primary testicular failure. This differentiation is of utmost importance, as obstructive azoospermia can be corrected by surgical ...
Behçet disease is a multi-systemic and chronic inflammatory vasculitis of unknown aetiology.
The mean age at which Behçet disease occurs is 20-30 years. The disease is most prevalent in the Mediterranean region, Middle East and East Asia. The highest incidence has been reported in...
Bladder and ureteric tuberculosis (TB) refers to infection of ureters and urinary bladder with M. tuberculosis.
characteristic beaded appearance due to alternate areas of strictures and dilatation (chronic state)
acute: ureteral wall thickening
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect. The severity of these defects is widely variable.
The estimated incidence of bladder exstrophy is 1:10,000-50,000 live births 4,6. There is a ...
Bullet and bodkin sign is the appearance of the ureter when there is an abrupt transition in the ureteral caliber. Bullet in the name is represented by the dilated proximal ureteric segment which appears to be perched on the constricted / non-dilated encased ureter which gives an appearance of a...
A burned out testis tumour may be present if there is metastatic retroperitoneal lymphadenopathy, but the primary testicular tumor is a relatively occult, scarred intratesticular focus. Approximately 50% of the "burned out" tumors continue to harbor malignant cells.
Calciphylaxis, or calcific ureamic arteriolopathy, is a rare condition which manifests as subcutaneous vascular calcification and cutaneous necrosis (small blood vessels of the fat tissue and the skin). Some authors describe as a syndrome of vascular calcification, thrombosis and skin necrosis.
Calyceal microlithiasis or more specifically renal calyceal microlithiasis is defined as <3 mm hyperechoic foci noted within the renal calyces on gray scale ultrasonography 1. It has been considered as a precursor for renal stone formation.
The patient may be asymptomati...
Cesarean section scar diverticulums are a defect in the lower uterine cavity at the site of the cesarean section scar.
in a study was found to be the only finding in patients with bleeding disturbances
Chronic kidney disease (CKD), also known as chronic renal failure, is a progressive loss of glomerular function caused by a long-standing renal parenchymal disease. It is present when the glomerular filtration rate (GFR) is less than 60 ml/min/1.73 m2 for three consecutive months or greater than...
Chronic periaortitis is an inflammatory condition which typically involves the infrarenal portion of the abdominal aorta. It is a rare disease usually occuring in middle-aged men.
It has various clinical presentations:
idiopathic retroperitoneal fibrosis (IRF)
perianeurysmal retroperitoneal f...
Chronic pyelonephritis is form of pyelonephritis where there are longstanding sequelae of renal infection. At the time of writing there is still no definitive consensus at to whether the condition represents an active chronic infection, arises from multiple recurrent infections, or represents st...
Clear cell sarcomas (CCS) of the kidney are a rare mesenchymal renal tumour that accounts for ~5% of primary renal neoplasms in paediatric population 1.
CCS is the second most common primary malignant renal neoplasm after Wilms tumour, with an annual incidence of 20 cases in the ...
Colovesical fistulas are communications between the lumen of the colon and that of the bladder, either directly or via an intervening abscess cavity (foyer intermediaire). When the communication is between the rectum and urinary bladder, the term rectovesical fistula is used.
Congenital urachal anomalies are a spectrum of potential anomalies that can occur due to incomplete involution of the urachus.
A urachal remnant occurs in approximately 1 in 5000 patients.
The urachus connects the dome of the bladder to the umbilical cord during fetal ...
Crossed fused renal ectopia essentially refers to an anomaly where the kidneys are fused and located on the same side of the midline.
The estimated incidence is around 1 out of 1000 births 1. There is a recognised male predilection with a 2:1 male to female ratio. More than 90% of...
Cryptorchidism refers to an absence of a testis (or testes) in the scrotal sac. It may refer to an undescended testis, ectopic testis, or an atrophic or absent testis. Correct localisation of the testes is essential because surgical management varies on location.
The testes develop i...
Cushing syndrome is due to the effects of excessive glucocorticoids which may be exogenous or endogenous.
In modern Western populations, iatrogenic steroid administration for treatment of inflammatory condition is the most common cause, e.g. asthma, rheumatoid arthritis.
Diabetes insipidus (DI) is the deficiency or resistance to the hormone vasopressin (antidiuretic hormone), which results in polyuria and polydipsia.
DI occurs in 3 per 100,000 people 2.
DI may be described as 1-3:
central/neurogenic/hypothalamic: vasopressin deficie...
Calcification of the ductus deferens can result from:
diabetes mellitus - most common
chronic infection - more frequently irregular and unilateral
chronic urinary tract infection
Emphysematous cystitis (EC) refers to gas forming infection of the bladder wall.
The condition is rare and usually confined to certain patient subgroups.
Risk factors include:
considered the commonest predisposing factor 6
may be present in ~50%...
Emphysematous pyelonephritis refers to a morbid infection of kidneys, with characteristic gas formation within or around the kidneys. If not treated early, it may lead to fulminant sepsis and carries a high mortality.
The patient usually presents with flank pain, urinary...
Epididymitis refers to inflammation of the epididymis, and may be associated with inflammation extending to the testis itself, in which case the term epididymo-orchitis is used. This should be distinguished from isolated orchitis, which is by comparison much less common.
Epispadias is a rare congenital anomaly that is almost always associated with bladder exstrophy.
It occurs in 1 in 30,000 births, with a male: female ratio of 3:1.
In males, three types are described - glandular, penile and complete. Glandular form is most...
Extramedullary hematopoiesis (EMH) is a physiologic compensatory event in many hematologic diseases. It occurs most commonly in the spleen, liver, and lymph nodes and less frequently in the lung, pleura, breast, thymus, small bowel, and central nervous system.1
EMH in the adrenal is uncommon,2...
Extrapulmonary tuberculosis (TB) refers to the haematogenous spread of Mycobacterium tuberculosis.
Extrapulmonary tubercuosis can occur as a primary form of the disease, i.e. direct infection of an extrapulmonary organ without the presence of primary pulmonary tuberculosis or it can ...
A fetal hydrocoele refers to an hydrocoele present in utero.
They may be sonographically identified in ~ 15% of male fetuses in the third trimester 6.
Often result from a patent processus vaginalis. They are more frequently unilateral.
Fournier gangrene is a necrotising fasciitis of the perineum. It is a true urological emergency due to the high mortality rate but fortunately the condition is rare.
Fournier gangrene is typically seen in diabetic men aged 50-70 but is rarely seen in women. Other than age, predisp...
Ganglioneuromas are fully differentiated neuronal tumours that do not contain immature elements and potentially occur anywhere along the peripheral autonomic ganglion sites.
On imaging, usually, they present as well-defined solid masses and can be quite large at presentation. Generally, they a...
The term germinoma usually refers to a tumour of the brain (WHO Classification of CNS tumours), but can also refer to similar tumours of the ovary and testis.
dysgerminoma of the ovary
seminoma of the testis
All three tumours share similar histology.
Granulomatosis with polyangiitis (GPA), previously known as Wegener granulomatosis, is a multisystem systemic necrotising non-caseating granulomatous vasculitis affecting small to medium sized arteries, capillaries and veins, with a predilection for the respiratory system and kidneys 3.
The renal manifestations of granulomatosis with polyangiitis (GPA) (previously known as Wegener's granulomatosis) are occult on imaging, especially when compared to the pulmonary changes. Approximately half of GPA patients have kidney disease at presentation. Granulomatosis with polyangiitis (We...
Granulomatous prostatitis is a nodular form of chronic prostatitis. It is usually diagnosed on biopsy.
Several classification systems exist. A frequently used clas...
Haematuria occurs when blood enters the urinary collecting system. There are many aetiologies for haematuria, and they range from benign and transient to gravely concerning. Haematuria can derive from the kidneys, ureters, bladder, prostate (in men), or urethra. Imaging can often be useful to de...
Hereditary breast and ovarian cancer (HBOC) syndrome is caused by mutation to either BRCA1 or BRCA2 genes. These patients have an increased risk of breast cancer, ovarian cancer, pancreatic cancer and prostate cancer. However, these gene mutations are not the only cause of hereditary breast canc...
HIV-associated nephropathy (HIVAN) is commonly seen in patients with HIV/AIDS and leads to end stage renal disease (ESRD). The diagnosis is not imaging-based and must be confirmed by renal biopsy.
HIVAN is seen in patients at advanced stages of HIV and AIDS, but it can also be see...
An horseshoe adrenal gland is very rare anomaly. It is also sometimes called a butterfly adrenal gland, fused adrenal gland or midline adrenal gland.
It is the solitary adrenal gland that is present in the midline with the fused portion either passing between the aorta and the inferior vena cav...
Hutch diverticula are congenital bladder diverticula, seen at the vesicoureteric junction, in the absence of posterior urethral valves or neurogenic bladder. They are though to result from a weakness in the detrusor muscle anterolateral to the ureteral orifice.
The occur almost e...
Hydroceles are acquired or congenital serous fluid collection between the layers of the tunica vaginalis surrounding a testis or spermatic cord. They are the most common form of testicular enlargement, and present with painless enlargement of the scrotum. On all modalities, hydrocoeles appear as...
Hydrocoele of the canal of Nuck is a rare condition in female children caused by a failure of complete obliteration of the canal of Nuck 1. The canal of Nuck is an abnormal patent pouch of peritoneum extending anterior to the round ligament of the uterus into the labia majora 2. Incomplete oblit...
Hypospadias refers to type of congential malformation affecting the male external genitalia.
The estimated prevalence is ~2 (range 0.2-4.1) per 1000 live births.
The urethral meatus is abnormally positioned proximally and ventrally to its normal position.
It is though...
Idiopathic retroperitoneal fibrosis (IRF) is a subtype of retroperitoneal fibrosis where no obvious cause is found. It includes a spectrum of diseases which are characterized by fibroinflammatory tissue encasing the abdominal aorta and the iliac arteries. This process may extend into the retrope...
Idiopathic scrotal calcinosis (ISC), sometimes called dystrophic scrotal calcinosis, is a rare benign condition characterized by superficial calcifications within the skin of the scrotum of unclear etiology, typically affecting men aged 20-40. The condition is primarily cosmetic, but may recur ...
Imperforate hymen is a congenital condition in which the hymen is without a normal central opening.
It happens in 0.1% of the female population, usually an isolated finding.
Primary amenorrhea with cyclic lower abdominal pain during menarche age. An imperforat...
Inflammatory myofibroblastic tumours (IMT), also known as plasma cell granulomas, are rare neoplasms that have a diverse spectrum of biological behaviour.
It can occur at any age and there is currently no recognised gender predilection.
Composed of spindle cells (key ...
Intrarenal reflux (IRR) involves intrarenal extension of vesicoureteral reflux (VUR) into the tubular system of the kidney.
IRR occurs in 3-10% of cases and can lead to renal injury, which may eventually result in renal scarring. The condition can be diagnosed by micturating cystourethrography ...
Intratesticular varicocele is a rare entity, occurring in ~2% of symptomatic population.
It is defined as dilated intratesticular veins seen in relation to the mediastinum testis and extending peripherally. It is usually seen in the presence of ipsilateral extratesticular varicocele....
Jackstone calculus is the name assigned to the appearance of a subset of urinary calculi.
Jackstone calculi are almost always composed of calcium oxalate dihydrate. They are nearly always created, and thus, located, in the bladder rather than the upper urinary tract.
They are compos...
Juxtaglomerular cell tumour (JGCT) is an infrequent renal tumour of the juxtaglomerular cells. These cells secrete renin and often cause severe hypertension and hypokalaemia.
JGCT affects all age groups, but is most common in adolescents and young adults, with peak prevalence in t...
Lacuna magna (a.k.a. sinus of Guérin) is a congenital blind-ended pouch located dorsal to navicular fossa of penis separated by fold and both share an external common opening to external urethral meatus. This diverticulum is located above and parallel to the urethra.
Although it ...
Leiomyoma of the urinary bladder is a rare benign tumour predominantly found in women, although men can also be affected. The most common presenting complaints are urinary voiding symptoms such as obstruction and irritation.
It exhibits characteristics similar to those of uterine leiomyomas on...
Leukoplakia of the urinary tract is a squamous metaplasia of the urothelium (keratinisation).
Clinically the condition presents with haematuria in one-third of cases, dysuria, frequency and nocturia, and thus it can mimic cystitis. Passage of the desquamated keratinised ...
Lithium-induced renal disease is characterised by a progressive decline in renal function, evidenced by increasing serum creatinine and decreased creatinine clearance. The lithium salt causes direct injury to the renal tubules. The duration of lithium therapy increases the risk of progression to...
Localised cystic renal disease (LCRD) or localised cystic kidney disease is an uncommon, non-familial, non-progressive disease characterised by clusters of cysts within normal renal parenchyma. It can be confused with unilateral autosomal dominant polycystic kidney disease (ADPKD), multilocular ...
Lymphangioleiomyomatosis (LAM) is a rare multi-system disorder that can occur either sporadically or in association with the tuberous sclerosis complex (TSC) and is often considered a forme fruste of TSC.
It almost exclusively affects women of child-bearing age 7. The estimated in...
Macronodular adrenal hyperplasia refers to a morphological type of adrenal hyperplasia in which there is adrenal enlargement in the form of large distinct nodules. It can be congenital or acquired.
A specific subtype under this entity is adrenocorticotropin independent macronodular adrenocortic...
Maiden waist deformity is the appearance of the deviation of bilateral ureters. This typically occurs in retroperitoneal fibrosis. In this condition, there is medial drawing of the ureter due to deposition of fibrous tissue in the lumbosacral junction. Due to involvement of both ureters, the cou...
Malacoplakia of the urinary tract is an uncommon chronic granulomatous inflammatory disease of the bladder wall. Malakoplakia (meaning "soft plaque") can affect any organ, but the urinary bladder is the commonest location.
Malacoplakia has a peak incidence in middle age and has a ...
Medullary sponge kidney is a sporadic condition where the medullary and papillary portions of the collecting ducts are dysplastic, and dilated and in most cases develop medullary nephrocalcinosis.
The incidence of medullary sponge kidney is estimated at ≈1:5000.
Mixed gonadal dysgenesis (MGD) is a type of gonadal dysgenesis characterised by gonadal asymmetry, and/or sex chromosomal mosaicism, as well as retained Müllerian ducts.
Depending on the chromosomal composition, patients may have testes and/or streak gonads.
Mixed epithelial and stromal tumour (MEST) of the kidney is an uncommon and recently recognised distinct neoplasm that should be distinguished from other renal neoplasms.
There is a female preponderance 10:1 1 with tumours occurring predominantly in middle-aged peri-menopausal wo...
Moth eaten calyx refers to the ragged, feathery calyceal outline due to irregular erosions of the calyx. It is one of the earliest excretory urographic appearance of genitourinary tuberculosis.
This appearance is due to necrotizing papillitis, which may further progress to form medu...
A mulberry stone is one of the types of urinary tract stones. It is formed of calcium oxalate dihydrate. It can be considered as a subset of a jackstone calculus which has a spiked appearance. When the stone has less well-developed spikes, it may appear to have a mamillated appearance, hence it ...
Multilocular cystic renal tumours (MCRT) are rare benign renal neoplasms occurring in a bimodal age distribution, involving young children and adults in the 4th and 5th decades.
For logical reasons, this article will discuss together the two ends of the spectrum of this disease, cystic partiall...
Neonatal hydronephrosis is most commonly diagnosed antenatally as fetal pylectasis, and in the majority of cases is due to pelvi-ureteric junction (PUJ) obstruction.
pelvi-ureteric junction (PUJ) obstruction (50% of cases 1,6)
vesicoureteric reflux (~20% of cases 5)
Nephroptosis, also known as floating or wandering kidney and ren mobilis, refers to the descent of the kidney more than 5 cm or two vertebral bodies when the patient moves from a supine to upright position during IVU 1-2.
Displacement can also occur medially across the midline, so-called medial...
Orchitis is an infection of the testicle, which is rarely isolated, and when in conjunction with the epididymis is called epididymo-orchitis.
Usually bacteria retrogradely seed into the testis from the bladder or prostate. Can also be secondary to viral infection (e.g. mumps, Coxsack...
A paintbrush appearance describes the streaky appearances of dilated contrast filled tubules within the renal medulla on IVP or CT-IVU. This appearance is characteristic for medullary sponge kidneys.
bouquet of flowers appearance
Papillary cystadenomas of the epididymis are the second most common benign tumours of the epididymis after adenomatoid tumours. They are more common in young men. Approximately 30% of the patients have von Hippel Lindau disease and approximately 10% to 40% of patients with von Hippel-Lindau dise...
A pelvic abscess refers to a collection of pus in the pelvis,
Some of the causes include
pelvic inflammatory disease (tubo-ovarian abscess)
inflammatory bowel disease
pelvic actinomycosis infection
Pelvi-ureteric junction (PUJ) obstruction/stenosis, also known as ureteropelvic junction (UPJ) obstruction/stenosis, can be one of the causes of an obstructive uropathy. It can be congenital or acquired with a congenital PUJ obstruction being one of the commonest causes of antenatal hydronephros...
Peyronie disease is the most common cause of painful penile induration. Fibrous tissue plaques form within the tunica albuginea, causing painful deformity and shortening of the penis. Though clinical diagnosis is usually accurate, the role of imaging is to evaluate extension of plaques, whether ...
Pheochromocytomas are an uncommon tumour of the adrenal gland, with characteristic clinical, and to a lesser degree, imaging features. The tumours are said to follow a 10% rule:
~10% are extra-adrenal
~10% are bilateral
~10% are malignant
~10% are found in children
~10% are familial
Pie in the sky bladder refers to the appearance of contrast opacified floating bladder seen high in the pelvis due to a presence of a large pelvic haematoma. This sign should raise concern regarding the possibility of an underlying urethral injury.
Posterior urethral valves (PUVs), also referred as congenital obstructing posterior urethral membranes (COPUM), are the most common congenital obstructive lesion of the urethra and a common cause of obstructive uropathy in infancy.
Posterior urethral valves are congenital and only...
Post transplant lymphoproliferative/lymphoproliferation disorder (PTLD) is increasing in prevalence as the number and survival length of solid organ and bone-marrow transplant recipients also increases.
It represents a variety of conditions varying from lymphoid hyperplasia to malignancy but is...
The Potter sequence is a constellation of findings demonstrated postnatally as a consequence of severe, prolonged oligohydramnios in utero.
It consists of
pulmonary hypoplasia: often severe and incompatible with life
growth restriction (IUGR)
abnormal facies (Potter fa...
Priapism is a term for a penile erection that occurs longer than desired. It may occur for multiple reasons, and the role of imaging in priapism is to distinguish between ischemic low-flow priapism (95%) and non-ischemic high-flow priapism (5%). In most cases only the corpora cavernosa are affec...
Primary hyperoxaluria, also referred as primary oxalosis, is a congenital autosomal recessive disease related to a liver enzyme deficiency leading to massive cortical nephrocalcinosis and renal failure.
Please, refer on secondary oxalosis for a discussion on the acquired form of hyperoxaluria....
Prostate specific antigen (PSA) is currently used as a tumour marker for prostate adenocarcinoma.
PSA is a 33 kilodalton glycoprotein produced in prostate epithelial cells. Its normal physiologic role is as a liquifying agent for seminal fluid and the normal amount in human serum is usually ver...
Prostatic abscesses can be a rare complication of prostatitis.
It has become relatively uncommon in clinical practice due to antibiotic therapy in those with prostatitis. It tends to affect diabetic and immunosuppressed patients. Most patients tend to present in the 5th to 6th de...
Prostatic calcification is a common finding, especially after the age of 50. They may be solitary but usually occur in clusters 7.
They are rare in children, infrequent below 40, and common in those over 50. Their number and size increase with age 8.
Prostatic carcinoma ranks as the most common malignant tumour in men and the second most common cause of cancer-related deaths in men. Prostatic adenocarcinoma is by far the most common histological type and is the primary focus of this article.
It is primarily a disease of the el...
Prostatic infarction refers to necrosis of the prostate gland tissue from a lack of blood supply.
Histology slices on biopsy specimens may show reactive atypia 3.
prostatic artery embolisation
presumed pelvic ischaemia after
cross-clamping of the aorta for coron...
Prostatitis refers to an infection or inflammation of the prostate gland that presents as several syndromes with varying clinical features. Prostatitis is a clinical diagnosis and imaging is useful to evaluate abscess formation.
The National Institutes of Health (NIH) classified prostatitis in...
Renal amyloidosis is rare as an isolated entity but can be associated with systemic amyloidosis. Renal involvement from amyloidosis in pathological specimens is quite common. However, renal function compromise is rare.
It usually manifests as nephrotic syndrome:
Renal arterial cut-off sign as the name suggests is an abrupt termination of the vascular contrast opacified renal arterial lumen. It may be associated with or without any contrast extravasation
It is seen in a vascular injury like segmental or main renal artery thrombosis or occlusion.
Renal arteriovenous fistulae (AVFs) are anomalous direct communications between arteries and veins in the kidney, which may be confused with a renal arteriovenous malformation (AVM).
The incidence of renal AVF is variable, estimated at 0.3-19% in native kidneys and 6-8% in ren...
Renal cell carcinomas (RCC) are primary malignant adenocarcinomas derived from the renal tubular epithelium and are the most common malignant renal tumour. They usually occur in 50-70-year-old patients and macroscopic haematuria occurs in 60% of the cases.
On imaging, they have a variety of ra...
Renal cysts are a common finding in the kidneys. Findings common to all "simple" renal cysts are well-marginated, thin walls with no enhancement of the cyst. They can be diagnosed on ultrasound, CT, or MRI. A cystic lesion in the kidney that deviates from the typical "simple" cyst appearance sho...
Renal hemosiderosis results from accumulation of hemosiderin in the kidneys.
Renal haemosiderosis is a known complication of the following conditions:
chronic intravascular hemolytic states such as haemolytic anaemias like sickle cell anemia and thalassemia 1,3
paroxysmal nocturnal hemoglo...