Keywords
disseminated - zoonosis - hydatid disease
Introduction
Hydatid disease is the most widespread zoonosis caused by tapeworm of genus Echinococcus
granulosus and E. multilocularis. While dogs are definitive hosts, sheep, cattle, goats, or humans may act as accidental
intermediate hosts.[1] Embryos released from eggs in the duodenum pass through the mucosa to reach the
liver through the portal venous system. Most of the embryos remain trapped in the
liver (50–70%), though the lungs (20–30%), kidneys (2–3%), spleen (0.8%), central
nervous system (0.5–2%), and bone (<10%) may become secondarily involved.[2]
[3]
[4]
We report an atypical case of a 12-year-old female with hydatid cysts involving the
liver, spleen, kidney, and paraspinal muscles simultaneously. Liver is the most common
site of involvement in adults. However, in over 60% of children, lung is the most
frequent site of disease and less than 10% have concurrent hepatic disease.[4] Multiple cysts occur in only 30% of cases and bilateral pulmonary cysts are rare.
Renal involvement is also infrequent in pediatric disseminated disease, constituting
only 1.9% of all cases.[4]
Case Report
A 12-year-old female was admitted to the Pediatrics Department of Shri Guru Ram Das
Institute of Medical Sciences, Amritsar in Northern India with complaints of abdominal
pain, irritability, vomiting, and prolonged cough in the past 1 year. No history of
tuberculosis contact could be elicited. Routine blood tests, erythrocyte sedimentation
rate, liver and renal function tests, and urinalysis were normal. Patient came from
a rural Indian background where cattle rearing is common practice. At presentation,
she had a temperature of 36.4°C, blood pressure of 110/86 mm Hg, pulse rate of 84
beats per minute, and respiratory rate of 38 breaths per min. Abdominal examination
revealed mild right upper quadrant abdominal tenderness and hepatosplenomegaly. Rest
of the systemic examination was normal.
Laboratory investigations revealed eosinophilia (18%) and the enzyme-linked immunosorbent
assay for antibody against E. granulosus was positive. Plain radiograph showed a large ovoid calcific lesion (calcified pericyst)
projecting over the liver ([Fig. 1]). On ultrasonography of the abdomen, liver was enlarged measuring 22 cm in size
in mid-clavicular line. Three well-defined round to oval thin-walled anechoic cystic
lesions were seen scattered in both lobes of liver (Type 1 Gharbi classification).
No evidence of calcification or hemorrhage was seen within the lesion. One of the
cysts showed few echogenic membranes floating within it (Type 2 Gharbi classification),
another showed fluid collection with septations (Type 3 Gharbi classification), while
one cyst was heterogeneous in echotexture (Type 4 Gharbi classification). Cystic lesion
was also seen in the splenic parenchyma at its upper pole, which showed a thin strand
within it (Type 2 Gharbi classification). Two cystic lesions were also noted at the
upper pole of left kidney (Type 1 and 2 Gharbi classification); one of the cysts appeared
to be communicating with the upper pole pelvicalyceal system. Mild hydronephrosis
with dilated upper ureter was also seen. On contrast-enhanced computed tomography
(CECT) abdomen, ultrasound findings were confirmed. Mild amount of subcapsular fluid
collection was noted ([Fig. 2]). Multiple cystic lesions were also noted in both lung fields, largely on the right
side (Type 1 and 2 Gharbi classification) ([Fig. 3]).
Fig. 1 Plain radiograph shows a large ovoid calcific lesion projected over the liver.
Fig. 2 On contrast-enhanced computed tomography, ultrasound findings were confirmed. All
the cystic lesions showed fluid density. The floating membranes and cyst walls show
mild degree of enhancement on postcontrast images. Left kidney shows few similar cystic
lesions and mild hydronephrosis with dilated upper ureter with abrupt tapering. No
calculus was seen in the ureter.
Fig. 3 Multiple cystic lesions in the visualized part of both lung fields more so on the
right side.
On the basis of the above findings, a provisional diagnosis of hydatid cyst with multiple
organ dissemination was made. Exploratory laparotomy was performed in view of compressive
symptoms caused by the cysts and all accessible cysts were removed. Medical therapy
with albendazole (400 mg q12h) and praziquantel (20 –75 mg/kg/day) was continued for
1 year without any significant complications. The child was regularly followed up
at 6 monthly intervals for 2 years, with no clinical, serological, or radiological
signs of recurrence.
Discussion
Although hydatid disease is widely endemic in the developing countries in South Asia
region,[4] there are only few reports on clinical characteristics and appropriate treatment
of this disease during childhood.[5]
[6] Multiple organ dissemination with hydatid cysts rarely occurs in pediatric patients
even in endemic areas.[7]
[8]
The atypical presentation of our case is demonstrated by the numerous and bilateral
cysts in the lungs along with hepatic, renal, and paraspinal muscle involvement.
The cysts were classified according to Gharbi classification as:
-
Type 1—Pure cystic fluid collection
-
Type 2—Fluid collection with membrane separation
-
Type 3—Fluid collection with septa
-
Type 4—Heterogenous pattern
-
Type 5—Completely calcified
Diagnosis can be easily made by ultrasonography and abdominal CECT.[7]
[9] CECT scan is advantageous over ultrasound as it is more sensitive and accurate,
and can easily detect calcifications, daughter cysts, and hydatid sand.[7]
[9]
Possible routes of primary hydatid infection of spleen include arterial route, venous
route or through systemic dissemination or intraperitoneal spread following ruptured
hepatic hydatid cyst.[10]
[11]
Management of disseminated echinococcus requires a multidisciplinary approach including
albendazole therapy, surgery, and PAIR (puncture, aspiration, injection, and respiration).[2]
[3] In our case, the multiple organ cysts were excised and medical therapy was continued
with albendazole (400 mg q12h) and praziquantel (20 –75 mg/kg/day) for 1 year, due
to extensive disease spread.
There is always a high chance of disease recurrence; therefore, continuation of medical
treatment with an oral benzimidazole antihelmintic agent is recommended for at least
3 months after surgery. Pediatric patients often present with atypical symptoms, as
in our case. Our patient had history of cough for the last 1 year and presented with
acute respiratory distress. Earlier case reports of multiorgan involvement with primary
dissemination have shown different approaches for disease management. Olmez et al
and Kaya et al used surgical approach along with medical treatment for disseminated
disease in children, as in our case.[2]
[6] It has been observed that PAIR procedure is associated with greater efficacy and
lower rates of complications than conventional surgery for the treatment of liver
hydatid cysts. The procedure also has been used successfully in the treatment of other
organs such as lungs and renal hydatid cysts. In the PAIR procedure, metronidazole
can be used with a similar effect as hypertonic saline on the membrane of hydatid
cyst.[6]
Anaphylactic reaction is a common complication of cystic hydatid disease and can occur
due to trauma, intraoperatively or spontaneous nontraumatic leakage of cystic contents.
Rupture of the cyst's contents evokes an allergic reaction that can range from minor
hypersensitivity to a fatal anaphylactic shock.[12]
Conclusion
In endemic areas, hydatid disease with systemic dissemination, though rare, should
be suspected while dealing with pediatric patients presenting with multiple cystic
lesions. History, clinical data, and imaging could assist the physicians to make a
definite diagnosis. Echinococcosis should be treated with either surgery or PAIR along
with an oral benzimidazole antihelmintic agent to remove the cyst successfully without
any complications and decrease the chances of recurrence.
