Double bubble, double trouble

Congenital duodenal obstruction - Advances in diagnosis, surgical management, and associated controversies

Congenital duodenal obstruction (CDO) occurs due to intrinsic and extrinsic mechanisms but is most often caused by intrinsic duodenal atresia and stenosis. This review will summarize the history, epidemiology, and etiologies associated with the most common causes of CDO. The clinical presentation, complex diagnostic considerations, and current surgical repair options for duodenal atresia and stenosis will also be discussed. Finally, both historical and recent controversies which continue to affect the surgical decision-making in the management of these patients will be highlighted.

Fatal Course of a Male Newborn with Double Duodenal Atresia

Multiple point duodenal atresia is an extremely rare condition with atretic segments in either two or three sites of the duodenum. We report a newborn male patient who presented to our institution with bilious vomiting, nonpassage of meconium, mild abdominal distension, and a palpable epigastric abdominal mass ∼1 × 1 cm. A faint double bubble was found on abdominal X-ray. On exploratory laparotomy, a duodenal cyst due to double duodenal atresia was found and a typical diamond-shaped duodeno-duodenostomy was created. A postoperative contrast study revealed passage of the contrast media into distal intestine. However, the patient died 2 weeks later due to uncontrolled sepsis and pneumonia. Despite the fact that multiple-point duodenal atresia is a rare condition, it should be considered as a differential diagnosis to avoid missed pathology.

Mimics of malrotation on pediatric upper gastrointestinal series: a pictorial review

Intestinal malrotation is a continuum of congenital anomalies due to lack of rotation or incomplete rotation of the fetal intestine around the superior mesenteric artery axis. The abnormal bowel fixation (by mesenteric bands) or absence of fixation of portions of the bowel increases the risk of bowel obstruction, acute or chronic volvulus, and bowel necrosis. The clinical presentation of patients with malrotation without, with intermittent, or with chronic volvulus can be problematic, with an important minority presenting late or having atypical or chronic symptoms, such as intermittent vomiting, abdominal pain, duodenal obstruction, or failure to thrive. The diagnosis is heavily reliant on imaging. Upper GI series remain the gold standard with the normal position of the duodenojejunal junction lateral to the left-sided pedicles of the vertebral body, at the level of the duodenal bulb on frontal views and posterior (retroperitoneal) on lateral views. However, a variety of conditions might influence the position of the duodenojejunal junction, potentially leading to a misdiagnosis of malrotation. Such conditions include improper technique, gastric over distension, splenomegaly, renal or retroperitoneal tumors, liver transplant, small bowel obstruction, the presence of properly or malpositioned enteric tubes, and scoliosis. All of these may cause the duodenojejunal junction to be displaced. We present a series of cases highlighting conditions that mimic malrotation without volvulus to increase the practicing radiologist awareness and help minimize interpretation errors.

Assessment of Toxicological Perturbations and Variants of Pancreatic Islet Development in the Zebrafish Model

The pancreatic islets, largely comprised of insulin-producing beta cells, play a critical role in endocrine signaling and glucose homeostasis. Because they have low levels of antioxidant defenses and a high perfusion rate, the endocrine islets may be a highly susceptible target tissue of chemical exposures. However, this endpoint, as well as the integrity of the surrounding exocrine pancreas, is often overlooked in studies of developmental toxicology. Disruption of development by toxicants can alter cell fate and migration, resulting in structural alterations that are difficult to detect in mammalian embryo systems, but that are easily observed in the zebrafish embryo model (Danio rerio). Using endogenously expressed fluorescent protein markers for developing zebrafish beta cells and exocrine pancreas tissue, we documented differences in islet area and incidence rates of islet morphological variants in zebrafish embryos between 48 and 96 h post fertilization (hpf), raised under control conditions commonly used in embryotoxicity assays. We identified critical windows for chemical exposures during which increased incidences of endocrine pancreas abnormalities were observed following exposure to cyclopamine (2–12 hpf), Mono-2-ethylhexyl phthalate (MEHP) (3–48 hpf), and Perfluorooctanesulfonic acid (PFOS) (3–48 hpf). Both islet area and length of the exocrine pancreas were sensitive to oxidative stress from exposure to the oxidant tert-butyl hydroperoxide during a highly proliferative critical window (72 hpf). Finally, pancreatic dysmorphogenesis following developmental exposures is discussed with respect to human disease.

Congenital duodenal obstruction: causes and imaging approach

Bilious emesis is a common cause for evaluation in pediatric radiology departments. There are several causes of congenital duodenal obstruction, most of which require elective surgical correction, but the potential of malrotation with midgut volvulus demands prompt imaging evaluation. We review the various causes of congenital duodenal obstruction with an emphasis on the approach to imaging evaluation and diagnosis.

True versus Pseudo-Intestinal Malrotation: Case Series and Review

Intestinal malrotation is an anomaly of fetal intestinal rotation that can present with symptoms after birth or in early childhood, but is rarely diagnosed in adults. Patients who have symptomatic presentations require surgery. Other entities may mimic intestinal malrotation and respond to non-surgical management. We present 2 adult cases with the radiological diagnosis of intestinal malrotation: one with true malrotation presenting as a duodenal mass, and another with "pseudo-malrotation" due to altered anatomy. These cases illustrate the importance of recognizing and differentiating these rare adult presentations of true malrotation from "pseudo-malrotation" in regards to their acute management.

Prenatal diagnosis of annular pancreas: reliability of the double bubble sign with periduodenal hyperechogenic band

OBJECTIVE

To evaluate the power of prenatal 2-D ultrasound examination in the 2nd trimester as a method of choice for accurate diagnosis of annular pancreas.

METHODS

Co-incidence of the double bubble sign (often accompanying gastroduodenal dilatation) together with a hyperechogenic band around the duodenum (corresponding with the tissue of annular pancreas) was used as a diagnostic criterion. Findings from postnatal surgery served for verification.

RESULTS

From 7,897 screened pregnancies, annular pancreas was proven in the cases where both signs were present, but never without the hyperechogenic band (N(1) = 3, N(2) = 3, p < or = 0.05). Sensitivity and specificity were 100%.

CONCLUSIONS

More multicentric studies are required to test this approach. The following diagnostic strategy is reasonable at the present time: when the double bubble sign is discovered, always suspect annular pancreas and look for the second sign: hyperechogenic bands around the duodenum. Also look for known associated anomalies, and vice versa, if any of associated anomalies are noted, also search specifically for the signs of annular pancreas.