Most individuals with situs inversus will live normally without repercussions. In fact, the abnormal anatomy is typically recognized incidentally when patients receive testing for unrelated health issues.

In the small group of patients with transposition of the great vessels or other congenital heart defects, the clinical presentation will include manifestations due to these specific anomalies.

In patients with Kartagener syndrome, defective cilia motility make it difficult to clear mucosal secretions, a manifestation that predisposes the patient to respiratory infections. Sinusitis is characterized by fever, cough, runny nose, headache, and facial pain.

Physical exam

In those with situs inversus, the location of specific diseases such as appendicitis and cholecystitis will present in different locations. The former will display symptoms in the lower left quadrant and the latter will appear in the upper left quadrant.

• Pain

  LIF pain could be appendicitis, RIF pain could be sigmoid diverticulitis and LUQ pain could be gall bladder related. Bruising over the right flank might mean you are worried about a splenic rupture. [ruralflyingdoc.wordpress.com]

  Abdominal pain is one of the most common complaints for patients in emergency department. It's difficult to make an accurate diagnosis by emergency physician in time, especially in patients with situs inversus totalis. [ncbi.nlm.nih.gov]

  Due to this malrotation diagnosis of the cause of abdominal pain in situs inversus totalis become difficult because pain localization becomes abnormal. [medcraveonline.com]

  In fact, between 18.4% - 31% of patients with situs inversus and midgut malrotation suffering from left-sided acute appendicitis exhibit a right lower quadrant pain [3-6]; the diagnosis often being delayed. [eurorad.org]

• Asymptomatic

  At 9-month follow-up a coronary computed tomography angiography confirmed the viability of all of the grafts, and one year after the operation the patient remained asymptomatic. [ncbi.nlm.nih.gov]

  E E Ekpe U Uwah E E Nyong Abstract Background: Dextrocardia and situs inversus are still rare congenital abnormalities that are asymptomatic and compatible normal life. [ajol.info]

  Presentation Female patient, asymptomatic, routine examination Patient Data Age: 65 Gender: Female Posterior anterior projection, the aortic arch and cardiac silhouette are projected on the right side, gastric bubble is also seen on the right side. [radiopaedia.org]

• Atrial Septal Defect

  It is associated with other complex cardiac anomalies and anatomical defects. A 30-year-old woman with this condition underwent mitral valve replacement and closure of a secundum atrial septal defect. [ncbi.nlm.nih.gov]

  Our patient was diagnosed with VACTER syndrome (horseshoe kidney, anal atresia with fistula, atrial septal defect, ependymal cyst) and SIT. [journals.lww.com]

• Fever

  2981Hasan Qayyum Emergency Department, Sheikh Shakhbout Medical City, Abu Dhabi, UAE Correspondence to Dr Hasan Qayyum; drqayyum{at}doctors.org.uk Abstract A 30-year-old man of African origin presented to our emergency department (ED) with subjective fever [casereports.bmj.com]

  The parents of a 2-year-old boy with a 3-day history of fever took him to the emergency department. The child's temperature fluctuated between 38°C (100.4°F) and 39°C (102.2°F). As part of the workup, chest films were taken. [patientcareonline.com]

  Symptoms of sinusitis include fever, cough, facial pain, congestion, etc. How is situs inversus diagnosed? Most of the patients will be diagnosed with situs inversus accidentally as part of a workup for something else. [symptoma.com]

  Acute rheumatic fever superimposed upon the above, presenting as an acute surgical abdomen and resulting in a left-sided appendectomy. 3. An electrocardiogram showing an upright P wave in Lead 1 in the presence of a left-sided superior vena cava. 4. [annals.org]

  There was no history of fever, vomiting, nausea, or weight loss. She did not report any similar episode in the past. Chest X-ray showed the presence of dextrocardia. [archbronconeumol.org]

• Pulmonary Valve Stenosis

  Associated malformations are variable and may include tetralogy of fallot, transposition of great vessels, pulmonary valve stenosis, ventricular and atrial septal defects, asplenia-polysplenia. [icd9data.com]

  […] right ventricle, total pulmonary venous defect and pulmonary valve stenosis. [ai-online.info]

  Associated malformations are variable and may include tetralogy of fallot, transposition of great vessels, pulmonary valve stenosis, ventricular and atrial septal defects, asplenia-polysplenia. And other defects. [icd10data.com]

  In pulmonary valve stenosis, there is a reduction in blood flow to the lungs due to an obstruction of the heart at the pulmonic valve. [en.wikipedia.org]

• Tachypnea

  […] hair laboratory examination Decreased head circumference Wheezing Round ear Phimosis Moderately short stature Macrodontia Premature birth Right bundle branch block Absent radius Short thumb Triphalangeal thumb Hypoplasia of the radius Bifid scrotum Tachypnea [mendelian.co]

• Abdominal Pain

  Abdominal pain is one of the most common complaints for patients in emergency department. It's difficult to make an accurate diagnosis by emergency physician in time, especially in patients with situs inversus totalis. [ncbi.nlm.nih.gov]

  pain which started on the day of attendance. [casereports.bmj.com]

  Case: 50-years old female with 1 year with history of abdominal pain who was diagnosed with biliary pancreatitis and situs inversus totalis during work-up for epigastric pain. Physical exam present with tenderness in left upper cuadrant. [sages.org]

• Left Lower Quadrant Pain

  62% of the patients presented with left lower quadrant pain, 14% with right lower quadrant pain and 7% with bilateral pain. [mjdrdypu.org]

  Left lower quadrant pain of unusual cause. J Emerg Med. 2001;20:241-245. 2. al-Khadra AS. Images in cardiovascular medicine. Mirror-image dextrocardia with situs inversus. Circulation. 1995;91:1602-1603. [patientcareonline.com]

  Left-sided acute appendicitis with situs inversus totalis: review of 63 published cases and report of two cases. J Gastrointest Surg, 14 (2010), pp. 1422-1428 [2] M.J. Nelson, G.R. Pesola. Left lower quadrant pain of unusual cause. [archbronconeumol.org]

  For example, in a patient with situs inversus, cholecystitis typically causes left upper quadrant pain, and appendicitis causes left lower quadrant pain. [emedicine.com]

• Regurgitation

  Pre-discharge echocardiography showed well-functioning mitral valve with no regurgitation. He was alive and well 6 months later. [academic.oup.com]

  Echocardiography revealed moderate mitral stenosis (MS) and moderate severe aortic stenosis (AS) and aortic regurgitation (AR). [aclr.com.es]

  Abstract Systemic right ventricular (RV) failure in patients with congenitally corrected transposition of the great arteries (ccTGA), a major cause of mortality in the long-term follow-up, is usually induced by concomitant severe morphologically tricuspid regurgitation [ncbi.nlm.nih.gov]

  Expand allCollapse all A 56-year-old male was referred for an esophagogastroduodenoscopy because of chronic heartburn, regurgitation, and epigastric abdominal pain. His past medical history was significant for chronic obstructive pulmonary disease. [cghjournal.org]

• Lower Abdominal Pain

  A 40 year old man was admitted with history of acute left lower abdominal pain, with uncontrolled diabetic keto-acidosis. Clinically, he was diagnosed as acute diverticulitis with localized peritonitis. [journalofmas.com]

  For example, if an individual with situs inversus develops appendicitis, they will present to the physician with left lower abdominal pain, since that is where their appendix lies. [wikidoc.org]

  CASE REPORT A 35-year-old woman was presented to surgical OPD with a history of acute lower abdominal pain, vomiting, and low-grade fever. [ncbi.nlm.nih.gov]

  A 35-year-old woman was presented to surgical OPD with a history of acute lower abdominal pain, vomiting, and low-grade fever. Per abdomen examination revealed tenderness in both iliac fossa with rebound tenderness and rigidity in left iliac fossa. [aeronline.org]

  A 28-year-old male patient presented to the emergency department with a 3 day history of lower abdominal pain and bloody diarrhea. [saudijgastro.com]

• Heart Disease

  Congenital abnormalities, such as primary ciliary dyskinesia, Kartagener type, polysplenia syndrome, biliary atresia, congenital heart disease, and midgut malrotation, as well as vascular anomalies (e.g. absence of retrohepatic inferior vena cava, preduodenal [orpha.net]

  Aug. 8, 2007. http://www.webmd.com/heart-disease/dextrocardia-with-situs-inversus Fuster, Valentin, Alexander, R. Wayne, O'Rouke, Robert, et. Al. The Heart. Chapter 81: Cardiovascular Diseases Caused by Genetic Abnormalities. [health.howstuffworks.com]

  PLAIN RADIOGRAPHIC DIAGNOSIS OF CONGENITAL HEART DISEASE Contents | Previous Condition | Next Condition 6a-1. Dextrocardia. (Legend.) Dextrocardia. The first reported case of dextrocardia was by Fabricius in 1606. [bcm.edu]

  Incidence of congenital heart disease in children born to residents of Olmsted County, Minnesota, 1950–1969. in: third edition. [ajconline.org]

• Pansystolic Murmur

  On his physical examination, grade 4/6 pansystolic murmur was heard all over the precordium, breath sounds were diminished. ECG showed atrial fibrillation (AF) with ventricular rate of 86/min. Chest X-ray showed dextrocardia (Figure 1A and 1B). [aclr.com.es]

  There was cardiac dullness on her right side and pansystolic murmur was heard at the apex. Heart sounds were louder on the right side of her chest. [jmedicalcasereports.biomedcentral.com]

• Heart Murmur

  Upon examination, arrhythmia and heart murmur may raise further suspicion of a cardiac abnormality. Non-cardiac symptoms include impairments of the liver and gastrointestinal tract. [en.wikipedia.org]

• Purpura

  This article aimed to report the coexistence of situs inversus totalis and idiopathic thrombocytopenic purpura. [journal.einstein.br]

  Immune thrombocytopenic purpura is an autoimmune disease with destruction of thrombocytes. This paper is presentation of surgical approach to a case with coexistence of these two conditions. 1. [hindawi.com]

  […] with situs inversus totalis. 61 Wang TT...Chen XD 31948815 2020 20 Hand-assisted laparoscopic radical nephrectomy for renal cell carcinoma in a patient with situs inversus totalis. 61 Chevli EM...Bodkin JJ 31788431 2020 21 Idiopathic thrombocytopenic purpura [malacards.org]

A majority of patients with situs inversus are diagnosed incidentally while undergoing workup for other underlying conditions while just a few cases may actually exhibit a clinical picture suggestive of this anomaly. For all patients suspected to have situs inversus and those with accidental findings, the assessment should include a personal and family history, a physical exam with special focus on the cardiovascular system and abdomen, and imaging studies.

Imaging

There are numerous imaging techniques that can be performed with the CT scan considered to be the confirmatory examination. This imaging modality provides key anatomic information such as the position of the cardiac apex and other organs as well as the branches of the vessels [12].

Complicated cases with cardiac defects are evaluated with MRI [13].

Other useful tools are the echocardiogram, ultrasonography of abdominal organs, and radiography[14] [15] [16] [17] [18].

Prenatal testing

Standard obstetrical ultrasonography is essential in the evaluation of the fetal anatomy. Hence, it will detect any lateralization abnormalities.

It is pertinent that the clinician and ultrasound technician are aware of any positive family history in order to thoroughly screen for this.

• Abnormal ECG

  Recognizing the presence of dextrocardia will also help avoid unnecessary workup for abnormal ECG. The editor of Images in Cardiovascular Medicine is Hugh A. [circ.ahajournals.org]

  Recognizing the presence of dextrocardia and situs inversus will help in preoperative assessment and will simplify interpretation of “abnormal ECG” in case of any postoperative emergency. [oooojournal.net]

No treatment is indicated for situs inversus unless the patient has congenital heart disease and associated complications, in which the specific therapy will depend on the cardiac anomaly and the clinical picture.

In order to provide excellent care to these patients, the medical team should be informed about the patient's anatomy prior to diagnosing abdominal disease or performing any surgical procedure.

Other

In patients with Kartagener syndrome, the bronchiectasis and sinusitis are managed and treated accordingly. For example, therapy should be directed at the facilitation of mucus clearance. Also, respiratory bacterial infections will require antibiotics.

When appearing as an isolated condition, situs inversus is associated with a good prognosis as patients are expected to live healthy lives with a normal life expectancy. If cardiac malformation is present, patients may be at an increased risk for morbidity and mortality depending on the specific type of heart defect. Additionally, congenital syndromes particularly featuring partial situs inversus may include anomalies of the midline axis, kidneys, and biliary structures.

Patients with Kartagener syndrome are susceptible to respiratory infections, which can lead to severe manifestations.

The etiology of this condition is not well elucidated but there are varied inheritance patterns observed across affected families. These mutations are most frequently present as an autosomal recessive trait although the disease has been transmitted through X-linked modes very rarely.

It is believed that the mutated genes responsible for this condition are present on chromosome 12. Specifically, these are the lefty genes, nodal genes as well as ZIC 3, ACVR2B and Pitxz genes [3] [4] [5] [6].

This lateralization defect occurs during embryogenesis when the tube structure that eventually develops into the heart loops in the reverse direction. The consequence is the organ displacement observed in situs inversus.

The incidence of situs inversus is estimated as approximately 1 in 8,000 to 1 in 25,000 live births [7].

In a majority of cases, dextrocardia accompanies situs inversus [8], and this type of the disease exhibits an incidence of 3% to 5% of congenital heart disease.

A commonly associated disorder, Kartagener syndrome, is present in 20% of situs inversus cases. Moreover, situs inversus affects half of individuals with this syndrome [7].

The normal anatomic placement of the heart and abdominal organs is referred to as situs solitus [1]. When the position of these visceral organs is inverted, this is defined as situs inversus. There are two main types of this condition which are classified according to the direction of the cardiac apical position at birth. Situs inversus with dextrocardia refers to an apical position displayed to the right while situs inversus with levocardia indicates that the apex is tilted to the left.

Situs inversus with dextrocardia is also known as situs inversus totalis. In addition to cardiac displacement, this type also features alternated lungs and reversed abdominal organs [9].

The arrangement of situs inversus is projected as a perfect mirror image. Therefore, the connection between the organs remains the same. As a result, they function normally.

Association with other disorders

Situs inversus may exist as an isolated disease but it can also present along with bronchiectasis and sinusitis to form the clinical triad typically observed in Kartagener syndrome. The latter is a result of a ciliary dysfunction. Normally, cilia in a region of the embrio called the node play a key role in establishing a left-right symmetry by producing a gradient in embryonic fluid. As one study reported, the immobility of nodal cilia may be responsible for the development of situs inversus [10].

Situs inversus can present concurrently with other congenital anomalies including renal dysplasia, pancreatic fibrosis, and intrahepatic dysgenesis [11].

Situs inversus is not preventable since it is the result of a genetic disorder.

Patients and unaffected family members may seek counseling to gain an understanding of the condition, what it entails, its possible complications, the possible modes of transmission, and other important details.

Note that clinicians treating individuals with situs inversus should be aware of its presence to avoid any confusion associated with location-dependent differential diagnoses.

Situs inversus refers to a rare condition, in which the thoracic and abdominal organs are positioned as a mirror image of the normal anatomy. Specifically, the term situs is defined as the position of the atrial chambers and the visceral organs [1] [2] whereas inversus describes the reversal of the chest and abdominal organs. Furthermore, this condition is classified into two types which are situs inversus with dextrocardia and situs inversus with levocardia with each representing the particular direction of the cardiac apex. Additionally, situs inversus encompasses various possibilities of disorders depending on whether the inversion applies to all organs or some.

This anatomic defect is caused by malrotation of the heart tube during fetal development. It occurs as a result of genetic mutations, which are often inherited through an autosomal recessive mode.

Individuals with situs inversus are asymptomatic unless they have congenital heart defects or other underlying diseases. Additionally, situs inversus is commonly found in patients with Kartagener syndrome or primary ciliary dyskinesia (PCD).

In most patients, situs inversus is identified coincidentally while undergoing investigative studies for other conditions. The workup includes a full medical and family history, a physical exam, and imaging techniques. The latter includes effective diagnostic tools such as radiography, ultrasonography, computed tomography (CT) scan, and magnetic resonance imaging (MRI).

Individuals without clinical manifestations don't warrant treatment. If concurrent congenital anomalies or other diseases are present, then these will require an appropriate management. Note that all clinicians providing care for the patient in all settings should be aware of the presence of situs inversus.

What is situs inversus?

Situs inversus is a condition in which the heart, lungs, and abdominal organs are reversed in a manner that is a mirror image of what the normal anatomy should appear as. For example, the heart is on the right side of the chest instead of the left. The right and left lungs are switched. The stomach, spleen, liver, and appendix may also be on opposite sides depending on whether the reversal includes all organs or just some.

What causes this condition?

The causes are not fully known but it is understood that there are abnormalities that occur during the fetal development.

Situs inversus is a genetic disease that is inherited in different ways. Most patients inherit this condition through an autosomal recessive pattern. This means that the patient must have two defective genes, thus receiving a bad copy from each parent.

What are the signs and symptoms?

Fortunately, if the patient has no heart defects, then s/he will have no symptoms. However, if there are abnormal heart structures, then the individual will experience complications due to those.

Also, it is important to note that 20% of patients with situs inversus will have Kartagener syndrome, which is a disease that makes it difficult for patients to clear their mucus secretions, which increases the risk of developing respiratory infections such as sinusitis. Symptoms of sinusitis include fever, cough, facial pain, congestion, etc.

How is situs inversus diagnosed?

Most of the patients will be diagnosed with situs inversus accidentally as part of a workup for something else.

There are numerous imaging tests that will diagnose situs inversus including:

• X-ray
• Ultrasound
• CT scan
• MRI
• Echocardiogram

Note that during the obstetric ultrasound, the clinician can detect situs inversus during the examination of the fetal anatomy. The parents will be made aware of the condition.

How is it treated?

When situs inversus exists by itself, there is no required treatment. When it appears with heart anomalies, the patients may require surgery and management of these anomalies.

Are there any special considerations?

The medical team should be aware of patients with situs inversus in order to provide excellent care to the patient.

What is the prognosis?

Again, if situs inversus is alone, there are no health issues. Patients live healthy lives and have a normal life expectancy.

Can it be prevented?

Since this is a genetic disorder, it cannot be prevented. Affected individuals and their family members can seek prenatal counseling to learn about the condition and how it is transmitted to future children.

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