3. ANOMALIES OF KIDNEY
CLASSIFICATION
A.Anomalies of renal number
1.Bilateral Renal agenesis
2.Unilateral Renal agenesis
3.Supernumerary kidneys
B.Anomalies of renal ascent
1.Simple Renal Ectopia
2.Cephalad Renal Ectopia
3.Thoracic Renal Ectopia
4. C.Anomalies of Renal form & fusion
1.Crossed renal ectopia with & without fusion
2.Horseshoe kidney.
D.Anomalies of Renal Rotation
E.Anomalies of Renal Vasculature
1.Aberrant, Accessory, or Multiple Vessels
2.Renal Artery Aneurysm
3.Renal Arteriovenous Fistula
5. F.Anomalies of Renal Collecting system
1.Bifid pelvis
2.Calcyeal diverticulum
3.Hydrocalycosis & Megacalycosis
4.Infundibulopelvis stenosis
7. TERMS IN CONGENITAL RENAL ANOMALIES
- RENAL AGENESIS: congenital absence of kidney.
- RENAL HYPOPLASIA: Congenitally small kidneys with a reduced
number of nephrons but normal architecture.
- RENAL DYSPLASIA: The presence of malformed renal tissue
elements , including primitive tubules , interstitial fibrosis with
or without the presence of cartilage in the renal parenchyma.
- RENAL HYPODYSPLASIA: Congenitally small kidney with
dysplastic features. Renal hypoplasia is more associated with
dysplasia than without .
8. UNILATERAL RENAL AGENESIS :
- It is common and not usually of any major health consequence ,
as long as the other kidney is healthy.
- It is associated with an increased incidence of mullerian duct
abnormalities of development of female reproductive tract and
can be a cause of infertility.
9. CLINICAL MANIFESTATIONS :
- No other symptoms at all.
- Premature birth
- Low set ears (this is because the ears and kidneys are formed
at same time in fetal development )
- The ureters may also be abnormal.
10. BILATERAL RENAL AGENESIS:
-It is the uncommon and serious failure of both fetus kidneys to
develop during gestation.
-it is more common in infants born to one or both parents with a
malformed or absent kidney .
-Males are commonly affected and most infants that are born
alive don’t live beyond four hours .
12. DIAGNOSIS :
-In a fetal ultrasound there will be a lack of amniotic fluid . Its
detected by USG at 12th week of gestation
13. MANAGEMENT :
- Periodic examinations of the kidney and prompt treatment of
any urinary tract infection is required.
- Blood pressure should be carefully monitored and elevations
treated.
- Dialysis or kidney transplant is preferred when the solitary
kidney has ceased to function.
- Counseling to avoid contact sports where the kidney could be
injured.
14. Supernumerary Kidney
The supernumerary kidney is truly an accessory organ with
its own collecting system, blood supply, and distinct
encapsulated parenchymal mass.
Pain, fever, hypertension, and a palpable abdominal mass are the
usual presenting complaints.
15. Anomalies of Renal Ascent
Simple Renal Ectopia
Failure of mature kidney to reach its normal location.
An ectopic kidney can be found in one of the following positions:
pelvic, iliac, abdominal..
Incidence 1 in 900. (L>R)
Mostly asymptomatic.
.Vague abdominal pain,Renal colic secondary to an obstruction,Hematuria & UTI.
16. Cephalad Renal Ectopia
.Subdiaphragmatic in position i,e immediately beneath the diaphragm near
the level of the 10th thoracic vertebra.
.
.The ureters are longer than normal & urinary drainage is not impaired.
.
Patients usually have no symptoms caused by malposition.
17. Thoracic Kidney
.Intrathoracic ectopia denotes either a partial or a complete protrusion of
the kidney above the level of the diaphragm into the posterior
mediastinum.
-The kidney usually lies in the posterolateral aspect of the diaphragm.
-Asymptomatic.
-Flank pain & Respiratory symptoms.
-The diagnosis is commonly made after a routine chest radiograph shows
the affected hemidiaphragm slightly elevated.
-CT or MRU is currently the imaging modality of choice.
.
18. Anomalies of Renal Form and Fusion
Crossed Renal Ectopia With and Without
Fusion
.When a kidney is located on the side opposite that in which its ureter inserts
into the bladder, the condition is known as crossed renal ectopia.
.90% of crossed ectopic kidneys are fused to their ipsilateral mate.
.2nd MC renal fusion anomaly after horseshoe kidney
.
19. McDonald and McClellan in 1957 proposed the categorization of crossed
renal ectopia into four groups:
1.crossed ectopia with fusion.
2.crossed ectopia without fusion.
3.solitary crossed ectopia.
4. bilaterally crossed ectopia.
20. CLASSIFICATION
When crossed renal ectopia with fusion occurs, the fusion anomalies are
classified as
(1) unilateral fused kidney with inferior ectopia.(MC TYPE)
(2) sigmoid, or S-shaped.
(3) lump, or cake.
(4) L-shaped,or tandem.
(5) disc, shield, or doughnut and
(6) unilateral fused kidneys with superior ectopia.(LEAST COMMON)
21. Horseshoe Kidney
.The horseshoe kidney is the most common of all renal fusion anomalies.
.Result of median fusion of metanephric tissue during early gestation
.1 in 400 individuals
.M:F ratio 2:1
22. Symptoms
.Asymptomatic in 50%
.symptoms typically related to hydronephrosis , infection or calculus formation.
.MC symptom is vague abdominal pain.
.UTI in 30% of patients.
.Calculi in 20% to 80% of patients
23. Diagnosis
PLAIN ABDOMINAL RADIOGRAPH
.low lying kidneys and close to the vertebral column with the lower poles
being more medial than in the normal kidney
USG
.Prenatal ultrasonography detects most horseshoe kidneys
.Postnatal ultrasonography detects the isthmus joining the two lower poles of
the kidneys in the midline.
.scanning horizontally along the midline in a craniocaudal direction,.
24. RADIONUCLIDE SCAN
.Demonstrates the abnormal axis of a horseshoe kidney.
.A continuous band across the midline is observed if the isthmus contains
functioning parenchyma
.
CT and MRU
Characterize the isthmus and further evaluate hydronephrosis.
MRA
Accurately delineate the vascular anatomy for preoperative planning
25. Anomalies of Renal Rotation
.The kidney and renal pelvis normally rotate 90 degrees ventromedially
during ascent so that the calyces point laterally and the pelvis faces medially.
.
.Failure of this allignment leads to malrotation.
• Malrotation is frequently associated with Turner syndrome.
26. Anomalies of Renal Vasculature
Renal Artery Aneurysm
.Rare & overall incidence is 0.1%.
• Mostly asymptomatic
.Treatment of RAA is indicated for those presenting with rupture or at high
risk for rupture.
.Risk factors for RAA rupture are
-Rapidly expanding RAA,
-RAA greater than 2 cm,
-Pregnancy, or those considering pregnancy
.
27. Anomalies of Renal Collecting System
1. Calyceal diverticulum is a cystic cavity within the kidney that is lined by
transitional epithelium and communicates with a calyx or, less commonly,
with the renal pelvis through a narrow isthmus.
2.Hydrocalycosis is a rare cystic dilation of a major calyx with a demonstrable
connection to the renal pelvis.
3.Megacalycosis is defined as nonobstructive enlargement of calyces
resulting from malformation of the renal papillae.
4.Infundibulopelvic stenosis is usually bilateral, and despite extensively
dysmorphic kidney features, the function is either normal or only slightly
affected.
28. Autosomal Recessive (Infantile)
Polycystic Kidney Disease
ARPKD is relatively rapid, symmetrical, and bilateral enlargement of
the kidneys in infants secondary to collecting duct cyst
Genetics
Mutations of a single gene, PKHD1 located on chromosome 6 (6p12)
The gene produces a protein called fibrocystin
(also known as polyductin)
Dysfunction of this protein mediates cystogenesis through dysfunction of the
primary cilia of renal epithelial cells. I
29. Clinical Features
1.Potter facies and deformities of limb
2.Respiratory distress
3.The effected new born has enormous , kidney shaped , hard non bosselated
flank mass and do not trans illuminate
4.Infant serum creatinine & BUN began to rise soon after birth
5.All patients with ARPKD have liver involvement in the form of
congenital hepatic fibrosis and vary in the degree of biliary ectasia and
periportal fibrosis.
30. Evaluation
. 1.In fetus and newborn, ultrasonography identifies bilateral, very
enlarged,diffusely echogenic kidneys, especially when compared with the
echogenicity of the liver .
2.The increased echogenicity is due to the presence of numerous microcysts
(created by tightly compacted, dilated collecting ducts) that result in
innumerable interfaces.
3.If the diagnosis is in doubt, CT is valuable because it is more sensitive to
inhomogeneity (and therefore to tumor) within abdominal masses
31. Treatment
1.No definite cure .
2.Respiratory care can ease or extend the child's life
3.Patients who survive may require treatment for hypertension, congestive
heart failure, renal and hepatic failure.
4.Hemodialysis and renal transplantation must eventually be
considered in many patients.
5.Severely affected neonates may require unilateral or bilateral nephrectomy,
because of respiratory and nutritional compromise
32. Autosomal Dominant (Adult) Polycystic
Kidney Disease
ADPKD is by far the most common inheritable form of renal cystic disease,
with an incidence of approximately 1 in 400 to 1000 live births.
Genetics
1.ADPKD caused by mutation in the genes PKD1 and PKD2.
2.PKD1 has been localized to the short arm of chromosome 16, with its gene
product being polycystin-1. (85% cases)
3.These patients typically have a more rapidly progressive form of the
disease, with cysts usually developing by the age of 20 year and ESRD
occurring in their 50s .
3.The PKD2 gene has been localised to the long arm of chromosome 4 and it
encodes the protein polycystin-2.(15% cases)
33. Clinical Features
Signs or symptoms first occur between the ages of 30 and 50 years .
1.Pain (flank/abdominal)is the most common symptom in adults.
.
2.Flank or abdominal mass.
3.Renal stones(20%).
4.Microscopic or gross hematuria is seen in 50% of patients.
5.UTI or Cyst infection
.
6.Hypertension is the MC clinical manifestation & about 50% of patients of 20
to 35 years age are hypertensive with normal renal function.
7.ESRD
34. Extrarenal Manifestations
1.Hepatic cysts, are the most common extrarenal manifestation of
ADPKD
2.Intracranial aneurysms(10% to 30%),predominantly Berry aneurysm.
3.Cysts may also occur in the seminal vesicles (40%), arachnoid
membrane(8%), and pancreas (5%).
4.Other abnormalities associated with ADPKD are mitral valve prolapse
and colonic diverticulosis
5. The incidence of RCC in ADPKD patients is no higher than that of the
general population.
36. When there is no family history to support a diagnosis of ADPKD, a
presumptive diagnosis can be made
If bilateral renal cysts are present and two or more of the following
symptoms are present as well:
1. bilateral renal enlargement, 2.three or more hepatic cysts,
3.cerebral artery aneurysm, and 4.a solitary cyst of the arachnoid, pineal
gland,pancreas, or spleen
CT or MRI (or both) are helpful and often superior to ultrasonography for
detecting cysts in organs other than the kidney.
37. Treatment and Prognosis
1.There is no definite cure.
2.Current therapy is directed toward lessening the complications of
ADPKD and delaying the onset of ESRD.
3.The complications of ADPKD can be reduced significantly by
controlling hypertension.
4.Tight BP control, the use of ACE inhibitors and/or ARB BP medication, and
the possible use of tolvaptan are the most current treatment options.
5.Chronic pain must be evaluated and entities such as infection, stone, and
tumor treated accordingly.
38. When conservative measures fail, surgical management must be considered.
1.USG or CT guided cyst aspiration,are both diagnostic and therapeutic.
2.Surgical unroofing of multiple or very large cysts can potentially alleviate
symptoms of pain
3.Surgical intervention appears only to improve symptoms and does not
appears to either accelerate the decline of renal function or preserve declining
renal function.
4.Nephrectomy is indicated for symptomatic patients with ESRD.
39. Juvenile Nephronophthisis and
Medullary Cystic Disease Complex
-Juvenile NPH and medullary cystickidney disease (MCKD) describe agroup
of genetic (inheritable) disorders with similar and unique characteristics.
-Similarities include the gross and histopathological appearance of the
kidneys, with the hallmark being interstitial fibrosis.
-Juvenile NPH and MCKD cause polydipsia and polyuria in more than 80%
of patients.
40. Nephronophthisis MCDK
1.AR 1.AD
2.ESRD in childhood or before 20yrs of
age
2.ESRD in 3rd or 4th decade
3.Extra renal manifestation
a)Retinitis pigmentosa
b)cerebellar ataxia
c)liver fibrosis
d)nocturnal enuresis
3.-NOT assosciated with extra renal
manifestations.
-Hypertension is present
41. Multicystic Dysplastic Kidney
MCDK is a developmental anomaly resulting in multiple cysts of varying
sizes,without identifiable normal renal parenchyma.
These kidneys have no function by definition, and usually the contralateral
kidney is normal and exhibits compensatory hypertrophy.
MCDK can be of two types: the infundibulopelvic type, with the atresia
involving the renal pelvis and the ureter, and the less common
hydronephrotic type, in which only the upper ureter is atretic .
42. Clinical Features
.2nd MC cause of an abdominal mass In infants.
.Incidence is 1 per 1000 to 4000 live births with M>F(55%-70%)
.The contralateral system frequently is abnormal.
C/L UPJO is found in 3% to 12% of infants
.C/L vesicoureteral reflux is seen in 18% to 43% of infants
.
.
43. Evaluation
- Prenatal ultrasonography, and in newborns ultrasonography is usually
repeated.
- Haphazard distribution of cysts of various sizes and without visible
communications among the cysts.
44. Treatment and Prognosis
1.Observation
2.Indication for Nephrectomy for MCDK
a)if a cyst has ruptured spontaneously or secondary to trauma (to relieve
pain or hemorrhage).
b) If large MCDKs compromising respiratory and digestive functions.
3.The natural history of MCDK is benign; approximately 40% of MCDKs will
spontaneously involute.
4.MCDK is not associated with an increased risk for
hypertension or neoplasm
45. Simple Cysts
Simple cysts are the most common cystic lesions found in the human
kidney
.
They are usually oval to round; may be solitary or multiple, unilateral or
bilateral; and are filled with plasma like clear or straw-colored fluid
46. Clinical Features
In children and adults, cysts are typically discovered incidentally on
ultrasonography, CT, or urography.
1.Abdominal mass or pain.
2.Hematuria secondary to rupture into the pelvicalyceal system.
3.Hypertension secondary to segmental ischemia.
4. Cysts can rupture into the pelvicalyceal system, maintain a communication,
and become a pseudocalyceal diverticulum.
47. Evaluation
USG criteria for
diagnosis of a classic benign simple cyst :
(1) absence of internal echoes,
(2) presence of a sharply defined, thin, distinct wall with a smooth and distinct
margin
(3) good transmission of sound waves through the cyst with consequent
acoustic enhancement behind the cyst, and
(4) a spheric or slightly ovoid shape
52. ECTOPIC URETER AND URETEROCELE :
- Distinct entities , but share many common features .
-Same underlying developmental mechanisms . .
- Similar clinical presetations .
-Approached in a similar manner.
.
53. :
INCIDENTAL .
- During evaluation for cause of general abdominal pain.
INFECTION
-UTI in first few months of life -MC presentation
INCONTINENCE
Caused by an ectopic ureter in a girl , but never in boys .
-Persistent low volume dampness at all time , child cant remain dry for even
30-60 mintues
54. -PAIN : Uncommonly associated with acute infection , episodic obstruction
of ectopic ureter or bladder pain caused by an obstructing ureterocele.
-PROLAPSE :Ureterocele prolapse unusual , smooth, congested , mucosa
covered interlabial masses protruding from urethra , non circumferential
non lobulated.
-LATE PRESENTATION :Infection , abdominal /flank pain , incontinence ,
stone in ureterocele.
55. EVALUATION
-Physical examination
-USG
.Typical findings-dilated upper pole with ureterlal dilation or dilated single
system.
.bladder images differentiate ureterocele from ectopic ureter-thin walled-
cystic dilation within the bladder,not extending beyond walls.
56. RENAL IMAGING
DMSA-
Gold standard for renal function assessment
IVU
Functional assessment only qualitative.
Ureterocele- a “cobra head” or “spring onion” configuration at bladder
level
VOIDING CYSTOURETHROGRAM (VCUG)
Duplicated collecting systems with lower pole reflux and non refluxing upper
pole , giving an apperance of a “drooping lily
ENDOSCOPIC EVALUATION
57. MANAGEMENT GOALS :
1)Preservation of renal function.
2) Elimination of infection , obstruction and reflux .
3)Maintenance of urinary continence.
4) Minimizing surgical morbidity.
58. DEFINITIVE SURGICAL OPTIONS :
-FOR ECTOPIC URETER: Common sheath reimplantation or
ureteroureterostomy . .
-FOR URETEROCELE :TUI , ureterocele excision and comon sheath
reimplantation or ureteroureterostomy .
59. DUPLEX URETER
-Common anomaly with incidence of 1 in 150births
-Unilateral more common than bilateral
-More common in girls
-In children associated with vesico ureteral reflux
-Two types
a)partial type
b)complete type
-”Weigert Meyer Law”
60. INVESTIGATIONS
-IVU is diagnostic.
-cystoscopy shows double ureteric orifices on same side.
TREATMENT
-Ureteric meatotomy .
-Co existing complications are treated.
-Ureteric reimplantation or partial nephrectomy if causing
incontinence in females.
61. Fibroepithelial Polyps
.Polyps of the ureter may manifest clinically with flank pain or hematuria or
by incidental detection of hydronephrosis.
• The most common site of attachment of a fibroepithelial polyp is at the
UPJ.
• UPJ polyps are best treated with pyeloplasty.
• Ureteroscopic removal of ureteral polyps .
62. Preureteral Vena Cava
Preureteral vena cava is commonly known as circumcaval or retrocaval
ureter.
Circumcaval ureter results from altered vascular, rather than ureteral,
development.
.This disorder involves the right ureter, which typically deviates medially
behind (dorsal to) the inferior vena cava.
.The renal pelvis and upper ureter are typically elongated and dilated in a “J”
or fishhook shape before passing behind the vena cava
. Treatment.
Surgical correction involves ureteral division, with relocation and
ureteroureteral or ureteropelvic reanastomosis.