Situs inversus totalis and ultrastructure of respiratory cilia: report of a cadaveric case.

Situs inversus totalis is the complete reversal of positions of major thoracic and abdominal organs. The present study reports the reversed structures and histology of the epithelium of bronchus of a female cadaver 87 years of age, which was found during the dissection in a medical course of gross anatomy. Opening the thoracic cage, the apex of heart was projected to the right side (dextrocardia) while the right and left lungs were alternated. Intra-abdominal organs were also completely alternated, as the liver situated on the left while spleen on the right and the same as the abdominal intestinal tract. The superior and inferior vena cavae located on the left side and drained blood into the left atrium. The azygos vein was on the right. The histology of the epithelium of bronchus and the transmission electron microscopy of the cilium ultrastructure were normal. Cardiac displacement seems to be associated with malrotation of the heart tube leads to dextrocardia and causes the inversion of positions of the thoracic and abdominal organs. The incidence of situs inversus totalis is approximately 1:10,000 and may be associated with primary ciliary dyskinesia (PCD) which refers to the dysfunction of cilia. PCD is also known as Kartagener syndrome (KS) which is characterized by situs inversus, bronchiectasis, chronic sinusitis and infertility, KS represents 20-25% of situs inversus totalis. However in the present study, the histology and ultrastructure of cilia appear normal.