DNB (Std.), Urology,
A fibro-inflammatory mass envelops and
potentially obstructs retroperitoneal structures,
including either or both ureters.
Fibrous, whitish plaque encases aorta, IVC &
their major branches, ureters, other
retroperitoneal structures, at times
intraperitoneal structures including GIT.
Centers around distal aorta at L4-L5 and wraps
around the ureters, leading to hydronephrosis via
extrinsic compression on the ureters or
interference with ureteral peristalsis.
Longitudinal- from renal hilum to pelvic brim(Aotic
bifurcation); may extend into the pelvis,
mediastinum and optic orbit.
Transverse-laterally to outer edge of psoas
AKA- Periureteritis fibrosa/plastica, Chronic
periureteritis, fibrous retroperitonitis, sclerosing
Ureteral obstruction in RPF appears minimal
despite severe renal failure. This suggests that
obstruction relates to impairment of normal
ureteric peristalsis by fibrotic tissue rather than
to mechanical obstruction.
Peak age of incidence: 40-60 years.
Rarely in children.
Male predominance; M:F Ratio 2-3:1
Estimated annual incidence: 1 per 200,000-
No racial predilection.
Idiopathic-70%(Ormond’s disease): Inciting
etiology not defined.
Definitive etiology in 30%.
Exact pathogenesis- unclear.
Good evidence: an immunologic response to
antigens within atherosclerotic plaques.
Vasculitis of adventitial vessels of aorta &
perioaortic small vessels → release of antigens
from atheromatous plaque such as ceroid, a
complex lipoprotein → induces an autoimmune
antigenic response → local inflammation &
Other immunologic events: CD3+ & CD20+
lymphocytes, IgG4-positive plasma cells
Immune reaction to an external agent:
Drugs/chemicals act as haptens-induce
hypersensitivity or immune reaction.
In Carcinoid tumor: result of circulating
serotonin or its metabolites.
Methysergide is a strong serotonin antagonist;
Rebound serotonin release after prolonged intake
may be an alternate mechanism.
Genetic influence- no major role, as no reports of
Non-specific signs & symptoms.
Duration of symptoms prior to diagnosis: 4-6
50% patients present with significant ureteric
obstruction & uremia.
M.C.symptom(92%)-dull, poorly localized,
noncolicky pain in flank, back, or lower abdomen.
Unrelated to posture; relieved by aspirin.
In children, pain may be referred to ipsilateral
hip or gluteal region, resulting in resistance to
Deep venous thrombosis
Weight loss, nausea, vomiting, anorexia, and
Raynaud phenomenon, ureteric colic, hematuria,
claudication, and urinary frequency: Rare.
Hypertension: Present in 50%
Presence of an abdominal mass (occasionally)
Ureteric obstruction with varying degree of renal
insufficiency: Earliest and M.C.organ involved.
Uncommon physical findings due to late
Peripheral edema or thrombosis
Small- or large-bowel obstruction
Spinal cord compression
Hypertension: results from many factors.
An increase in renin release secondary to
In some patients, volume-dependent
hypertension may result from obstructive
Obliteration of psoas shadow & an enlarged
renal outline due to hydronephrosis.
INTRAVENOUS UROGRAPHY (IVU):
The classic triad (18-20%)
1. U/L(20%) or B/L(68%) hydronephrosis,
2. Medial deviation of middle third of ureters,
3. Tapering of ureter at L4/L5 level.
IVU shows medial deviation of middle part of both ureters
Demonstrates poor distensibility of ureter.
Delineates PCS anatomy; performed prior to
stent insertion to decompress the kidneys.
Interestingly, very little resistance is
encountered during ureteric catheterization
despite extensive extrinsic fibrosis.
RGU reveals smooth
narrowing and medial
shift of ureter
Obstruction of lymphatic flow at L3/L4 level,
Opacification of collateral channels,
Nonvisualization of lymphatics above L4 vertebra,
Delay in passage of contrast through iliac and para-
Simple noninvasive modality used to assess
response to therapy.
RPF appears as a retroperitoneal, extensive, well-
defined, hypoechoic mass centered over the sacral
Degree of hydronephrosis and hydroureter may
Doppler ultrasonography has no role in
differentiating benign from malignant RPF.
Most frequently used imaging method for
diagnosis & follow-up of RPF.
o RPF appears as a plaque that is isodense with
o envelops aorta & IVC b/w the renal hila & sacral
o usually extends laterally to incorporate ureters.
o Obliteration of the fat plane between the mass
and the psoas muscle may be observed.
o Plaque may show a variable degree of
enhancement, depending on stage of the disease.
Significant enhancement in the early active
vascular stage, but poor in the late avascular
NCCT scan: periaortic fibrotic reaction associated
with an inflammatory aortic aneurysm &
bilateral ureteric stents
Unenhanced CT in RPF: Note hydronephrosis and
soft tissue mass indistinguishable from the great
MAGNETIC RESONANCE IMAGING:
o T1-weighted images: Both benign and malignant
RPF have low-to-intermediate signal density
o T2-weighted images vary based on disease stage.
Early stage- signal density is high because of
high fluid content & hypercellularity.
o Late-stage disease has low T2 signal intensity as
a result of avascular acellular fibrosis &
decreased fluid content.(majority of plaque is
composed of fibrosis)
WHY MRI IS SUPERIOR TO CT IN RPF:
Independent of patient’s renal functional status.
More accurately distinguishes the plaque from
the great vessels than unenhanced CT.
The disease can be followed without radiation
exposure of repeated CT.
Enhancement ratios can be calculated with
dynamic gadolinium enhancement; can be used
to assess disease activity & monitor treatment
18-FDG PET SCAN:
o 18F-fluorodeoxyglucose positron emission
tomography (F-18 FDG PET) detects glucose
o Degree of inflammation in the plaque, which may
predict response to immunosuppressive therapy
as well as its therapeutic response.
oCan also reveal other sites of disease (thyroid,
thorax) and may help to identify the most
appropriate sites for retroperitoneal biopsy.
Gallium-67 single photon emission–computed
tomography (SPECT) scintigraphy
In the acute phase, RPF may take up gallium-67,
due to binding of gallium-67 to lymphocytes.
o Evaluating responses to medical therapy of RPF.
o Detection of recurrent disease.
o Demonstrates both the mass lesion and its
Core tissue biopsy (histologic confirmation) is
preferred over FNAC assessment.
RPF progresses through 2 clinical stages:
(1) Early inflammatory phase: an inflammatory
infiltrate(both perivascular and diffuse)
contains macrophages, lymphocytes, plasma
cells, and occasional eosinophils; highly
vascular & cellular.
(2) Late fibrotic phase: avascular & acellular with
scattered calcification and fibrous scarring.
consists of myofibroblasts and type-1 collagen.
Submucosal edema and lymphocytic infiltration
may be observed in the ureter.
Malignant RPF: scattered nests of malignant
cells within the inflammatory infiltrate.
Goals of m/m:
1. to preserve renal function.
2. to prevent other organ involvement.
3. to exclude malignancy, and
4. to relieve symptoms.
Treatment of retroperitoneal fibrosis depends
on disease stage at diagnosis, & patient’s
Patients with hydronephrosis and uremia-
Emergency decompression by PCN or Indwelling
Close monitoring for post-obstructive
diuresis(Urea diuresis, Sodium diuresis), renal
function status, & appropriate fluid & electrolyte
Search for inciting cause; offending drugs
Imaging & Biopsy to rule out malignancy.
Empirical therapy includes corticosteroids,
tamoxifen, and azathioprine;
cyclosporin, medroxyprogesterone acetate, and
Glucocorticoids and azathioprine: most useful in
patients with signs of inflammation (eg, raised
ESR and WBC count and positive ANA results)
Beneficial effect: due to anti-inflammatory action & ability
to inhibit fibrotic tissue maturation.
A standard protocol is prednisolone at 40-60 mg/d tapered
to 10 mg/d within 2-3 months and discontinued after 12-24
Prednisolone oral 60 mg on alternate days for 2 months,
tapered to 5 mg daily over next 2 months. The latter dose is
continued for a total of 2 years.
Methylprednisolone pulse therapy (MPPT) at 1 g/d IV for 3
days along with azathioprine or penicillamine.
Steroids can be used in combination with surgery.
Characteristic clinical response to steroid
therapy: resolution of pain and constitutional
symptoms within days after treatment, a rapid
fall of erythrocyte sedimentation rate, and
Tamoxifen increases the synthesis and secretion
of transforming growth factor–beta (TGF-b), an
inhibitory growth factor, by human fetal
fibroblast in vitro.
Other possible mechanisms of action: inhibition
of protein kinase C, reduction of epidermal
growth factor production, inhibition of
calmodulin, and blockage of growth-promoting
Blocks the proliferation of T cells and B cells.
Surgical Management: Open Ureterolysis
Midline, transperitoneal abdominal incision.
Preoperative RGC placement to facilitate
identification & dissection.
Bilateral ureterolysis, even if single ureter
After B/L ureterolysis, repositioning of ureters &
protection from fibrous entrapment.
Lateral retroperitonealisation: retract the
ureters laterally and secure the overlying
peritoneum medially to the psoas muscle to
maintain the ureters in this location.
Intra-peritonealisation: close the peritoneum
behind the ureters so that the ureters may be
displaced anteriorly into the peritoneal cavity.
Omental wrap: In extensive RPF cases,
surround the ureters with omentum and
reposition them within the peritoneal cavity.
Ureteral wrap in PTFE vascular graft/Gore-
Removal of ureteric stents 6-8 weeks after
Postop Steroid therapy may be considered to
High-risk & elderly patients- long term ureteral
Ureterolysis not possible d/t extensive fibrosis &
o Ileal substitution
o Appendix substitution
o Renal autotransplantation.
If lower ureter involved- Boari’s flap.
Poor Kidney function despite salvage
decompression & N contralateral kidney-
Further Outpatient Care:
Biochemical markers (CRP, ESR, renal function)
monitored every 4-8 weeks to assess response.
Radiologic assessment (CT, MRI) performed
every 3 months; once disease stabilized, scanning
can be repeated at 6 months.
Recurrence reported as late as 10 years; thus,
long-term follow-up is necessary.
Renal failure patients- early Nephrology referral
& continued follow-up.