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Pyloric stenosis

Case contributed by Dr Suman Bandhu


Projectile, non bilious vomiting 2 weeks. Voracious appetite with no weight gain. No response to treatment for gastroesophageal reflux.

Patient Data

Age: 5 weeks
Gender: Male

Ultrasound images of upper abdomen dedicated for the pylorus of the stomach

The stomach pylorus is prominent, clearly identified medial and posterior to the gall bladder. The pyloric canal is lengthened to a length of 18-20 mm. A single muscle wall measures 5 mm. The pyloric transverse diameter is 16 mm. There is mild shouldering at the proximal end of the pylorus. The pylorus resembles the uterine cervix. (cervix sign)

A diagnosis of hypertrophic pyloric stenosis was made based on the ultrasound and clinical picture.

Case Discussion

Hypertrophic pyloric stenosis is idiopathic thickening of muscular layer of the pyloric canal with failure of relaxation of the pylorus.

Presentation is at 4-6th week of life, with projectile, non bilious vomiting and voracious appetite. In persistent undiagnosed cases serious symptoms of dehydration and hypochloremic alkalosis, electrolyte imbalance and failure to thrive. This becomes a medical emergency and urgent preoperative electrolyte balance correction is needed to prevent peri-operative risk.

Surgical pyloromyotomy is the treatment of choice. This is usually laparoscopic.

Ultrasound is the modality of choice for diagnosis.

The hypertrophic pylorus is better seen than the normal pylorus, medial and posterior to the gall bladder.

Dynamic ultrasound shows static appearance of pylorus over time with failure of relaxation of the pylorus. Distal passage of gastric contents is not demonstrable.

The most specific ultrasound sign is a single muscle layer thickness of more than 3 mm. Other signs are pyloric length more than 15 mm and transverse diameter more than 13 mm.

Based on the imaging and clinical picture a diagnosis of pyloric stenosis was made.

The patient underwent urgent surgical pyloromyotomy. The symptoms disappeared and the baby gained weight after surgery.

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Case information

rID: 80181
Published: 16th Jul 2020
Last edited: 16th Jul 2020
Inclusion in quiz mode: Included

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