Fluid levels are not visible in: (A) Meconeum ileus, (B) Intussusception, (C) Colon pouch, (D) Duodenal obstruction
Answer is A. In meconium ileus meconium is so thick that it is unable to form air-fluid level despite complete small intestinal obstruction (Note the multiple air-fluid level is a feature of mechanical small bowel obstruction & paralytic ileus).