King Edward Memorial Hospital - Departments: Radiology

Radiology

Case of the Month

Case No. :	40
Month :	April
Year :	2002
Contributor :	Dr. Soni Chawla

Other Cases

Clinical Features | Discussion | Symptoms |Signs | Investigation | Sonography | Complications

Clinical Features:

A 24-year-old woman presented to the emergency department of this hospital with a history of four months’ amenorrhea and pain in the abdomen -mainly in right hypochondriac region, fever and vomiting for past three days. The pain was colicky, intermittent, with high grade fever and non-bilious vomiting about 6-8 times a day. The patient was pale and febrile with a pulse of 104/min; the blood pressure was 110/70mm of Hg. There was tenderness in the right hypochondriac region and the Murphy’s sign positive. The fundus uterus was felt above pubic symphysis.

Her blood investigations revealed hypochromic, microcytic anemia and leucocytosis.

Radiological examination: A sonographic examination of the abdomen was performed first. On placing the probe over the right hypochondriac region, a tubular, tram-like echogenic structure with wriggling motions was noticed in the common bile duct (CBD) [fig1].

Fig. 1

During the ultrasound examination, the patient suddenly became restless as she experienced a severe agonizing colicky pain in the right hypochondrium. She also had tachycardia, palpitations and perspiration. At this time, the tubular echogenic structure in the CBD was moving with active wriggling motion from the CBD through the cystic duct and reached the gall bladder lumen [Figs 2,3,4].


Fig. 2	Fig. 3

Fig. 4

The gall bladder was distended with peri-cholecystic fluid and the sonographic Murphy’s sign was positive. The intrahepatic biliary radicles were normal.

A similar tubular structure was noted in the duodenum which was confirmed by a high frequency superficial probe. The rest of the abdominal scan was normal. A normal live intra-uterine gestation of a gestational age of about 15-16 wks was also seen.

Based on the history, clinical findings, laboratory investigations and sonographic findings, a diagnosis of acute cholecystitis in a case of biliary ascariasis in a pregnant woman with anemia was made.

The patient was put on conservative line of management and given anti helminthic drugs. Following this, the patient responded well. She vomited two worms and passed four to five worms in her stools. The patient was discharged after six days. A repeat sonogram showed no worms in biliary system, gallbladder or elsewhere in the abdomen.

Discussion

Ascariasis is caused by the parasite - Ascaris lumbricoides - commonly called the round worm. The prevalence is as high as 1 in 4 of the world’s population. More than 1 billion people are infected with the intestinal round worm. The prevalence is about 90%. in the Ganges valley.

The adult male worm measures about15-25cm in length and adult female about 25-35cm.The female lays about 200,000 eggs per day. The life cycle is as follows: [Fig 5]

Symptoms:

Early [4-16 days of ingestion of eggs]:	-Fever -Cough -Wheezing.
Late[6-8week after ingestion ]:	--Vague abdominal complaints such as: cramping, nausea, vomiting. -Small bowel obstruction. -Pancreatitis. -Cholecystitis -Appendicitis.

Signs:

Passage of abdominal worms from migration or in stools.
-wheezing .
-mild abdominal tenderness.

Investigations:

1. Stool examination -eggs and adult worms.
2. Chest Radiograph-Loeffler's syndrome
3. Abdominal radiograph-calcified worms
4. Sonography
5. Barium examination-ribbon like filling defects
6. ERCP-diagnostic as well as therapeutic.
7. CT Scan of abdomen-to evaluate complications .

Sonography shows following signs :

1.Inner tube sign-The worm is seen as a thick non shadowing echogenic stripe with a central anechoic tube (GIT of the worm).

2.Stripe sign-Thin, non-shadowing stripe without an inner tube .

3.Spaghetti sign-Overlapping longitudinal interfaces in the main bile duct due to coiling of a single or several worms in the CBD.

4.Bulls Eye sign-Seen as echogenic halo around anechoic centre on transverse scan of the worm.

5.Segmentation-The worm seems to be segmented due to wriggling movements on real time USG.

6.Fragementation-Dead worms are seen as multiple fragments.

7.Wriggling motion in real time USG-The most diagnostic sign.

Complications :

1.Intestinal obstruction or perforation
2.Acute cholecystitis
3.intermittent biliary obstruction
4. Liver abscess
5.stricture of hepatic ducts

10% of patients having abdominal ascariasis have biliary ascariasis. 40%of these patients having biliary ascariasis develop dreaded complications if not diagnosed and treated in time.

The diagnosis being simple by means of USG where in a high index of suspicion is required to pick up various signs seen on USG and treatment being antihelminthic drugs.