A congenital condition of complete side-to-side reversal of major thoracic and abdominal organs to a mirror image position, while front-to-back position remains normal. It is rarely symptomatic unless associated with other abnormalities, which may include primary ciliary dyskinesia, Kartagener syndrome, dextrocardia, congenital heart defects, diaphragmatic hernia, and abnormalities of spleen, kidney, and pancreas. Situs inversus is present at birth but may not be diagnosed until a chest x-ray is performed or as symptoms present.