Fetus in Fetu: A Rare Presentation in an Adult Female

Abstract

A report of Fetus in fetu (FIF) by Murtaza et al.1 in Oman Medical Journal 25 (2010) was an interesting presentation. One must congratulate the authors for a good presentation. There are however some areas to be highlighted for the benefit of the scientific world. The patient presented by Murtaza A at al.1 is not the oldest patient in the literature to date. Hoeffel at al.2 review shows that only four of 88 reported cases (4.5%) have been described in patients 10 years of age or older, with the oldest reported case occurring in a 47year old man.3 The patient presented by Murtaza A et al.1 was 30 years old. Various authors up to 2007 have quoted less than 100 reported cases as aftermath of Hoeffel at al.2 extensive review published in 2000, which documented 88 cases. A similar but more recent review of reported FIF from 1806 to 2007 by Rahman GA et al.4 isolated one hundred and sixty (161) cases with the ages of diagnosis ranging from 16 Weeks in utero to the oldest of 47 years. Braimoh et al.5 in 2008, described comprehensively the distribution of the 170 published cases of FIF by site of occurrence (1806 to July 2008) and found the occurrence of abdominal location in 80.3%. Unlike the Hoeffel et al with 4.5% above the age of 10 years, Rahman GA et al.’s review had twelve of the 160 reported cases (7.5%) described in patients 10 years of age and above.4 Interestingly the patient reported by Murtaza A et al.1 is from Nagpur, India. In the 2007,4 review 25.6% of cases were from Asia with 37.5% of cases from Asian Countries coming from India. It was found to be rare in Africa, where only three cases were reported before 2007 (all from South Africa). However, two cases were reported from Nigeria in 2008.5,6 The West African sub region with largest population of blacks and the largest twinning rate in the world had no documented case before 2007.4 The size of cases excised weighed between 13 grams and 2000 grams,4 the case reported by Murtaza A et al.1 is one of the largest. We agree with Murtaza A et al1 that computer tomography (CT) is a very useful imaging modality but may not be the most reliable. Although there has been limited report on the use of magnetic resonance imaging (MRI) in the diagnosis of FIF probably due to the rarity of the entity, MRI, which has major advantages of allowing imaging in the saggital and coronal planes and capability to identify insufficiently calcified vertebrae and vertebral axis7 seems to be the ideal technique for demonstrating the wide range of tissue within such lesion. In reviewing the literature, most case reports up to 1980 showed that the preoperative diagnosis of FIF was made only in 16.7% of cases and in fact up to mid-1990s, fewer than a quarter of the cases were diagnosed prior to surgery2 because CT and MRI scans were not performed. Both of which, have enhanced the accuracy of preoperative diagnosis.