The Coexistence of Pituitary Adenoma and Rathke’s Cleft Cyst with Situs Inversus Totalis: A case presentation and review of literature

Abstract Background Situs inversus totalis (SIT) is a rare anatomical condition affecting the positioning of internal organs. Rathke’s cleft cyst (RCC) and pituitary adenoma (PA) are the most common brain diseases, but the coexistence of PA and RCC is extremely rare. To our knowledge, SIT with PA and RCC has never been reported. Case presentation We retrospectively analyzed a case of SIT with Cushing's disease and RCC in a 65-year-old woman. The main complaints were centripetal obesity and limb weakness for two months. Heart ultrasonography (USG), chest, and abdominal CT revealed a mirror image of internal organs. In view of the elevated cortisol level, the cortisol suppression tests were applied to confirm the diagnosis of Cushing’s disease. Magnetic resonance imaging (MRI) demonstrated a pituitary microadenoma and a cystic lesion (RCC). Endoscopic endonasal surgery was done and the final pathology confirmed both lesionsascorticotroph adenoma and RCC respectively. However, whole-exome sequencing (WES), including mitochondria, did not return a positive result for adrenocorticotropic hormone (ACTH). At the three months post-operative follow-up, the patient’s weight had decreased by 3.5 kg and symptoms were significantly reduced. PA with co-occurrence of RCC is very rare. Of the patients who underwent PA surgery at the Tangdu hospital from 2015 to 2020, only five cases were reported to also have RCC (0.5%). Conclusions In this single-case study, we describe a woman with confirmed SIT who also has manifestations of hypercortisolism, which was eventually confirmed to be PA combined with RCC. In view of the possibility of a gene mutation leading to SIT during embryonic development, and since RCC and PA are also considered to occur in this period, although this patient did not find any abnormal genetic variations, we still can't rule out that the abnormality in this case is caused by abnormal development of early embryos.