Introduction
Situs inversus totalis (SIT) is a rare congenital abnormality, where
there is transposition of both the thoracic and the abdominal organs,
thus forming a left-right asymmetrical picture of the normal anatomical
placement of the organs.1 It is kept under an umbrella
term, heterotaxia, which encompasses all congenital disorders associated
with malposition about the left-right axis.2 An
important distinction is from simply situs inversus, where only some of
the major abdominal and thoracic organs are reversed from their normal
anatomical positions.3 SIT is even more of a rare
condition, with an incidence of 1:10,000, and males being affected more
than females (1.5:1).1 Due to this anatomical
asymmetry, it may pose difficulties during diagnostic and therapeutic
procedures.1,3
Situs inversus totalis appears to be familial and laterality is
established early on in the developmental process, during gastrulation.
A protein, namely “Sonic Hedgehog” (Shh) is deemed to be responsible
for the expression of two growth factors, Nodal and Lefty. If these
proteins are released on the right side, the rotation of the heart
occurs to the left side. However, if they are released on the left side,
rotation occurs to the right. A gene named PITX2 has been identified,
which controls the secretion of Shh and Nodal.4 The
exact mechanism behind this is yet unknown, however, it has been
speculated that the mutation in the PITX2 and Nodal gene is responsible
and is also associated with other conditions like primary ciliary
dyskinesia (PCD) and Kartagener syndrome.1,3,4,5
Due to the unique transposition of the anatomical structures in SIT, the
usual causes of abdominal pain may be a misdiagnosis. Similarly, these
patients with cholelithiasis may have a presentation, with left upper
quadrant pain, instead of the usual right, likely posing a diagnostic
dilemma.6,7 Operative management in SIT patients also
presents with technical and ergonomic challenges, especially for
right-handed surgeons.8 The mirror image of the
anatomy causes difficulty in the dissection of the Calot’s triangle,
thus requiring appropriate tweaks to the normal preoperative and
intraoperative setting.8 This report describes a case
of a SIT patient with symptomatic cholelithiasis, managed by
laparoscopic cholecystectomy.