Situs ambiguous, levocardia, right sided stomach, obstructing duodenal web, and intestinal nonrotation: a case report

Cilia and Nodal Flow in Asymmetry: An Engineering Perspective

Over the past several years, cilia in the primitive node have become recognized more and more for their contribution to development, and more specifically, for their role in axis determination. Although many of the mechanisms behind their influence remain undocumented, it is known that their presence and motion in the primitive node of developing embryos is the determinant of the left-right axis. Studies on cilial mechanics and nodal fluid dynamics have provided clues as to how this asymmetry mechanism works, and more importantly, have shown that direct manipulation of the flow field in the node can directly influence physiology. Although relatively uncommon, cilial disorders have been shown to have a variety of impacts on individuals from chronic respiratory infections to infertility, as well as situs inversus which is linked to congenital heart disease. After first providing background information pertinent to understanding nodal flow and information on why this discussion is important, this paper aims to give a review of the history of nodal cilia investigations, an overview of cilia mechanics and nodal flow dynamics, as well as a review of research studies current and past that sought to understand the mechanisms behind nodal cilia's involvement in symmetry-breaking pathways through a biomedical engineering perspective. This discussion has the additional intention to compile interdisciplinary knowledge on asymmetry and development such that it may encourage more collaborative efforts between the sciences on this topic, as well as provide insight on potential paths forward in the field.

Dextrocardia With Situs Inversus in a COVID-19 Patient

With an estimated incidence of one in 10,000 to one in 50,000 patients, Situs inversus totalis (SIT) is a rare innate anomaly, portraying a mirror image of the normal anatomy, as the cardiac position and abdominal viscera are completely inverted. Despite the fact that physicians and researchers have been dealing with the SARS-CoV-2 pandemic for three years, there is a lack of published data examining the potential effects of anatomic variations on coronavirus disease 2019 (COVID-19) infection. This study aimed to contribute to this domain by presenting a rare case of a COVID-19 infection coexisting with SIT as one of the very few cases reporting the simultaneous presence of the two pathologies. We sought to present this case of COVID-19 in a quinquagenarian female, in whom SIT was an incidental radiological finding. The reversed anatomy did not seem to affect the clinical progression of the virus. However, due to the lack of scientific evidence, the potential long-term effects, if any, of COVID-19 on SIT cannot be predicted. The recognition of the mirror pattern will offer a personalized treatment plan, reducing the risk of severe complications and management mishaps.

Secundum Atrial Septal Defect Closure via the Transhepatic Approach in a Patient With Situs Ambiguus and a Left-Sided Inferior Vena Cava

Secundum atrial septal defect (ASD) is the most common type of ASD. Symptoms including dyspnea on exertion usually manifest in the third and fourth decade of life. The transcatheter closure is the treatment of choice for secundum ASD. The transfemoral venous approach has been the mainstay. However, this approach can be challenging or impossible in patients with congenital absence or interruption of the inferior vena cava (IVC). The latter has been reported in patients with situs ambiguus and inversus. In this patient population, other forms of venous access such as the transjugular or transhepatic approach are used. We present a unique case of symptomatic secundum ASD in a patient who was incidentally found to have situs ambiguus with a left-sided intact IVC. An initial attempt at the ASD closure via the transfemoral approach was unsuccessful due to acute angulation. A repeat attempt was successful via the transhepatic approach with the guidance of real-time ultrasound, transesophageal echocardiogram, and the involvement of an interventional radiologist. The procedure was well tolerated without any complications. Repeat transthoracic echocardiogram with agitated saline the day after the procedure was negative for interatrial shunting.

Neonatal intestinal obstruction associated with situs inversus totalis: two case reports and a review of the literature

Background

The association of neonatal intestinal obstruction with situs inversus totalis is extremely rare with only few cases reported in the literature to date. This association poses dilemmas in management. We present two such cases (of Indian origin), and briefly discuss the pertinent literature and measures to prevent unfavorable outcome.

Case presentation

Case 1: a 1-month-old preterm (1300 g) male neonate belonging to Hindu (Indian) ethnicity presented with recurrent bile-stained vomiting, non-passage of stools and epigastric fullness. A babygram and upper gastrointestinal contrast studies revealed situs inversus and suggested proximal jejunal obstruction with midgut volvulus. Exploration confirmed situs inversus totalis along with reverse rotation and midgut volvulus. There was a small gangrenous area in the proximal jejunal loop. A Ladd’s procedure, resection of the gangrenous jejunal loop, and jejunojejunal anastomosis was performed. Note was made of the unusual appearance of the intestines suggestive either of fibrous or fatty infiltration. Postoperatively, our patient developed septicemia and died.

Case 2: a 4-day-old female neonate belonging to Hindu (Indian) ethnicity, small (1320 g) for gestation, presented with history of non-passage of meconium since birth, refusal to accept feeds, and episodes of recurrent bilious vomiting with abdominal distension. A plain radiogram revealed situs inversus and proximal jejunal obstruction. Ultrasonography of her abdomen revealed renal dysplastic changes in both her kidneys. Laparotomy confirmed multiple jejunoileal atresias with situs inversus totalis. Resection anastomoses was performed for multiple atresias. Our patient passed a few pellets of meconium stools postoperatively; feeds were started gradually on the sixth day. Our patient gradually developed oliguria and renal failure, followed by respiratory distress and generalized edema requiring ventilatory support. She died later due to multiorgan failure.

Conclusions

Clinicians should have high index of suspicion for malrotation with midgut volvulus or intestinal atresias in neonates of situs inversus presenting with bilious vomiting. The surgical treatment should follow the same surgical principles. In situs inversus, because of transposition of viscera, midgut volvulus may occur in an anticlockwise direction, hence derotation is performed clockwise. Prognosis was poor in our series because of low birth weight, late presentation, presence of gangrenous locus in the small bowel and development of septicemia in our first case and multiorgan fibrosis/dysplasia in our second case. Early diagnosis and timely referral is paramount for favorable outcome.