Human cysticercosis is a neglected tropical parasitic disease due to the tapeworm Taenia solium, common in endemic developing countries. Cysticerci are most commonly found within the central nervous system, but they may also localize in a variety of tissues, including the tongue. Here, we described a case of a 21-year-old woman with a painless, firm, smooth, mucosa-colored nodule located in the lateral region of the tongue was seen by a dentist. An excisional biopsy was performed, and the surgical specimen was examined histomorphologically. The analysis revealed the presence of a cystic lesion containing a serrated larva ( Cysticercus cellulosae) as well as a cystic capsule with predominantly mononuclear inflammation. The morphological findings were consistent with the diagnosis of cysticercosis of the tongue. The patient was followed for 22 months and showed no signs of recurrence.
Infection with Taenia solium, which causes intestinal taeniasis and tissue cysticercosis, comprises two different life cycle stages and clinical entities in the human host. Normally, the adult tapeworm completes the larval phase of its life cycle in pigs and is then transmitted to humans via the ingestion of undercooked contaminated pork; once inside the human host, the parasite develops into a tapeworm in the intestine [
The accidental ingestion of eggs by humans via fecal contamination of the fingers, food or water or through the reflux of proglottids from the intestine leads to the presence of eggs in the stomach, where the resultant embryos penetrate the mucosa and are dispersed by the blood or lymphatics, leading to cysticercosis. In humans, cysticerci are most commonly found within the central nervous system, where they produce a pleomorphic clinical disorder known as neurocysticercosis [
A 21-year-old woman from Poções County (Bahia, Brazil) reported to a private dental center with the chief complaint of a painless nodule on the right side of her tongue that had been present for the past two years. The nodule had increased in size to approximately 3.5 cm in maximum diameter, and clinical examination showed a firm nodule that was covered with normal mucosa (
A preliminary diagnosis of lipoma was made, and an excisional biopsy was performed, with a well-delimited nodule with free surgical margins detected during surgery (
An analysis of hematoxylin/eosin-stained histological sections revealed the presence of a cystic lesion containing a serrated larva (C. cellulosae) with a cuticle and well-defined areolar and cellular layers (
The patient was referred for clinical evaluation. The coproparasitological exam was negative for eggs and proglottids of T. solium and other pathogens. A chest X-ray and computed tomography showed no calcified cystic areas. The patient was followed for 22 months and showed no signs of recurrence.
Parasitic infections are endemic and represent a major public health problem in developing countries. In particular, human infections with T. solium occur worldwide, mainly in rural communities in developing countries in Central and South America, most parts of Asia (including the Indian subcontinent and China), Eastern Europe, and most of Africa, especially in those areas with poor sanitation where humans and animals live in close contact and in those regions where inspection of meat is not strictly enforced. Imported cases mostly occur in developed areas due to immigration from and tourism to endemic regions [
Humans are the definitive host of the adult form of the T. solium helminth, and pigs are the intermediate host of the larval stage. However, humans can become an accidental intermediate host of T. solium when viable eggs of the parasite are ingested. The eggs emerge in the intestine and are transported through the bloodstream to their destination, which is generally the heart [
It is important to stress that the risk of infection is present only when pigs are raised in a rural household environment in the absence of good hygiene, not in industrial herds or in large agricultural areas that are subject to strict sanitary control. In addition, the immigration of people from endemic to non-endemic regions has resulted in an increase in the number of cases in some industrialized countries where this condition was considered to be almost eradicated. The patient described here lives in a small rural town located in the southwest region of Bahia State (Brazil). However, she reported no contact with pigs.
Few cases of cysticercosis involving oral tissues have been reported in the literature. Similar to the present case, the tongue appears to be the most frequently affected site [9,12], and cysticercosis of the tongue should always be included in the differential diagnosis for patients who live in endemic areas and present nodular formations in the mouth. Despite the small number of cases described, the clinical manifestations of oral cysticercosis are consistent with the symptoms observed in the present case, i.e., a firm, slow-growing nodule with well-defined margins covered with normal-color mucosa that is a symptomatic. With respect to age and gender, patients in their second decade of life seem to be more affected [
The differential diagnosis for oral cysticercosis includes salivary gland tumors and mucoceles, in addition to neurofibroma, vascular tumors, fibroma, lipoma, leiomyoma and schwannoma [9,10]. When cysticercosis is diagnosed in oral tissues, serological and coprological tests and imaging exams are essential for the detection of systemic disease [
Fine-needle cytology may aid diagnosis when the larval tegument is aspirated. In the study conducted by Mazhari et al. (2001), 153 patients with cysticercosis were diagnosed using only this technique [
Treatment of cysticercosis might be unnecessary in asymptomatic patients [