A full-term infant presented with severe abdominal distention. Supine radiograph of the chest and abdomen show a large rim-calcified mass representing a meconium pseudocyst (Fig. 1, thick arrows). The irregular linear calcifications, mostly in the left upper quadrant, are calcified meconium in the peritoneal cavity adherent to bowel walls (small arrow). Surgical and pathological findings confirmed small bowel obstruction secondary to segmental volvulus with walled-off small-bowel perforation and pseudocyst formation.

Fig. 1
figure 1

Supine radiograph of the chest and abdomen

Full size image

Meconium peritonitis is caused by antenatal bowel perforation with spillage of meconium into the peritoneum causing a sterile peritonitis and formation of dystrophic calcifications [1]. Common causes of bowel obstruction and perforation include meconium ileus, bowel atresia, and segmental volvulus. When the extruded meconium becomes walled off, it can form a rim-calcified mass representing meconium pseudocyst [2].