The clinical presentation of renal hydatid disease is usually
non-specific and related to the mass effect of the enlarging
cyst. Abdominal and lumbal pain is the most frequent
presenting symptom
4. The only pathognomonic sign of
renal hydatid disease is hydatiduria, which occurs when the
cyst communicates with the collecting system; this has been
reported in 5% to 28% of patients
5,6 Preoperative
definitive diagnosis for renal hydatid disease is difficult even
when all investigations were performed. The diagnosis is
usually made with imaging and serologic studies.
There is no specific laboratory finding of renal hydatid
disease. Moderate eosinophilia is non-specific, although
present in 20-50% of cases. Indirect hemagglutination test
and enzyme-linked immunosorbent assay are the most
sensitive tests, although they commonly provide both falsepositive
and negative results3. Recently counter
immunoelectrophoresis against arch-5 gained wide
acceptance7.
However, despite modern imaging methods, isolated
renal hydatid disease might still cause diagnostic dilemma
like mentioned as in our first case. Among imaging studies,
CT is the most valuable diagnostic examination8. CT
findings include a thick, calcified cyst wall, a unilocular cyst
with detached membrane, multiloculated cystic formation
with mixed density, and daughter cysts with lower density
than the mother cyst9.
Medical management of renal hydatidosis is far from
being a realistic alternative to surgery and should be
considered as adjuvant therapy. Pretreatment with
albendazole is very important as the cyst material becomes
nonantigenic, decreasing the chance of anaphylaxis.
Pretreatment also decreases tension in the cyst wall; thus,
reducing the risk of spillage. The recommended dose of
albendazole is 400 mg twice daily for 4 weeks2. However,
we administered albendazole after surgery in our first case
Surgical options include simple cystectomy, pericystectomy,
partial or total nephrectomy. Cyst removal without
contamining the patient is the goal of therapy because rupture
of a cyst also causes alergic manifestations that vary from
pruritus and urticaria to anaphylactic shock even death10
Before the main surgical procedure three different scolocidal
agents can be injected into the cysts; 3% hypertonic saline
solution, 10% povidon iodine solution, and 95% ethanol. A safely cleavage plane have been to obtained between cyst and
normal renal tissue. Renal sparing surgery is possible in a
significant proportion of cases - as in our cases. Total
nephrectomy is inevitable in case of significantly destroyed
renal parenchyma by pressure from cyst2.
Gupta et al.11 described a rare case of isolated renal
hydatid cyst presenting as perinephric and iliopsoas abscess
and discussed the dilemma in diagnosis. An another interesting
case of a giant renal hydatid cyst is presented in our
second case. Patient presented with the complaint of right
flank pain for three years and for a pain in right gluteal region
for a year. The big cystic mass detected at kidney and gluteal
region.
A serologic survey is necessary for the follow-up of operated
patients. It increases the efficiency of the treatment.
Specific antibodies increase 4 to 6 weeks after surgery, after
which they decrease slowly for the next 12 to 18 months.
Persistently high specific antibody titers or a secondary increase
in the antibody titers 6 to 12 months after surgery
indicate a relaps12.
Our conclusion is that not all hydatid cysts present
with the charasteristic radiological findings and hydatid cysts
can be found in unusual localization. In order to prevent
iatrogenic echinococcal dissemination all precautions must be
taken during operation.