Cerebral sparganosis in children: epidemiological, clinical and MR imaging characteristics

Recent update on cerebral sparganosis: A bibliometric analysis and scientific mapping

Human sparganosis, a parasitic infection prevalent in Asia, can progress to cerebral sparganosis, a severe condition with significant neurological symptoms. Diagnosis and treatment are challenging due to its clinical similarity to other infections, highlighting the need for improved detection and management strategies. The aim of this study was to observe research trends, key contributors, gaps in the existing knowledge, diagnosis challenges, effective treatment options, and prevention strategies, providing recommendations for future research directions and clinical practice improvements on cerebral sparganosis. A bibliometric analysis was conducted by extracting 139 documents from the Scopus database in June 2024. The retrieved data were analyzed using the R package's Bibliometrix (Biblioshiny) and VOSviewer. Spanning 97 different sources, the research exhibited an annual growth rate of 2.5%. Annual scientific production revealed fluctuating research activity with peaks in 2010 and 2011 and notable citation peaks in 1996 and 2005, indicating pivotal studies that significantly influenced subsequent research. Early studies focused on diagnosis and specific parasites, while recent studies (2010-2024) have increasingly addressed clinical outcomes, treatment strategies, and advanced diagnostic techniques. Trends revealed a shift towards clinical and diagnostic advancements, with recent emphasis on diagnostic imaging, immunoassays, and the relationship between cerebral sparganosis and brain tumors. In conclusion, the studies on cerebral sparganosis underscore the potential for enhancing clinical practice by improving diagnostic accuracy, informing treatment decisions, and implementing targeted screening efforts based on epidemiology and risk factors. Recommendation to further study needs to notify the cerebral sparganosis in high-risk countries with similar socioeconomic and cultural characteristics to endemic regions, including Indonesia.

Surgical treatment of a patient with live intracranial sparganosis for 17 years

Background

The incidence of sparganosis, especially intracranial live sparganosis is very low in China. Due to the lack of typical clinical manifestations, it is difficult to make a clear preoperative diagnosis of the disease, which often leads to delays the disease and serious consequences.

Case presentation

A 23-year-old man presented with a 17-year history of intermittent seizures and right extremity numbness and weakness. Magnetic resonance imaging (MRI) showed patchy, nodular and line-like enhancement. Enzyme-linked immunosorbent assay (ELISA) detected positive antibodies to Spirometra mansoni in peripheral blood and cerebrospinal fluid (CSF). In addition, during the operation, an ivory-colored live sparganosis was removed under the precise positioning of neuronavigation, and the patient was diagnosed with cerebral sparganosis. The patient began praziquantel and sodium valproate treatment after the operation, and was followed up for 3 months. There was no recurrence of epilepsy, and the weakness and numbness of the right limb improved.

Conclusion

Nonspecific clinical manifestations often make the diagnosis of cerebral sparganosis difficult, and a comprehensive diagnosis should be made based on epidemiological history, clinical manifestations, ELISA results and imaging findings. Surgery is the preferred method for the treatment of cerebral sparganosis, and more satisfactory results can be achieved under the precise positioning of neuronavigation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07293-7.

Migration characteristics as a prognostic factor in cerebral sparganosis

OBJECTIVE

To differentiate diagnostic and prognostic factors from the clinical material of patients with cerebral sparganosis in central South China.

METHODS

Consecutive patients with cerebral sparganosis from our hospital between 2010 and 2018 were retrospectively enrolled. The clinical manifestations, radiographic features, treatment, and outcomes of these patients were analyzed.

RESULTS

Thirty patients with cerebral sparganosis were included, and foci migration on magnetic resonance imaging was detected in 22 patients, from whom we observed 4 migration modes: interlobar migration (50.0%, 11/22); transmidline migration (27.3%, 6/22); transventricular migration (13.6%, 3/22); and cerebellum-brainstem migration (9.1%, 2/22). The percentage of good outcomes was higher in patients with live worm capture than in those without live worm capture (75.0%, 12/16 vs 33.3%, 2/6). Exposure to preoperative antiparasitic medication was associated with worm migration toward the cortical surface, which led to a higher probability of live worm capture.

CONCLUSIONS

We propose 4 modes of sparganosis migration that are correlated with worm capture and neurologic prognosis. We found that exposure to antiparasitic medication was associated with worm migration toward the cortical surface, leading to a higher probability of live worm capture. These observations suggest a novel significance for preoperative medication of cerebral sparganosis.

Lesionectomy for cerebral sparganosis and concomitant epilepsy: A case series of 15 patients

OBJECTIVE

To report the clinical characteristics and surgical outcomes of patients with cerebral sparganosis and concomitant epilepsy.

METHODS

We retrospectively collected the clinical data of all patients with cerebral sparganosis and concomitant epilepsy who underwent lesionectomy as treatment at Xiangya Hospital, Central South University between January 2015 and August 2019. Seizure outcomes were evaluated according to the International League Against Epilepsy (ILAE) classification. ILAE classes 1 and 2 were defined as favorable seizure outcomes, whereas ILAE classes 3-6 were defined as unfavorable seizure outcomes.

RESULTS

Fifteen patients with cerebral sparganosis and concomitant epilepsy who underwent lesionectomy as treatment met the inclusion criteria. Live worms were surgical removed in 80 % of patients. With a mean follow-up of 2.4 ± 1.1 years, 66.7 % of patients demonstrated favorable seizure outcomes, with improvement of symptoms other than seizures. Longer seizure duration associated with unfavorable seizure outcomes.

CONCLUSIONS

Lesionectomy is an effective treatment for patients with cerebral sparganosis and concomitant epilepsy. Early surgical treatment may offer more benefits to such patients.

A Retrieved Sparganum of Spirometra erinaceieuropaei from a Korean Man during Mechanical Thrombectomy

Human sparganosis is a zoonotic disease caused by infection and migration of the plerocercoid of Spirometra spp. Although sparganosis were reported from most parts of the body, the sparganum parasitizing inside cerebral artery is remarkably uncommon. We report a case of cerebral intravascular sparganosis in an elderly patient with acute ischemic stroke who was diagnosed by retrieving sparganum during mechanical thrombectomy. Finally, the parasites were identified as Spirometra erinaceieuropaei using multiplex PCR and cox1 gene sequencing.

Occurrence of Kalicephalus, Strongyloides, and Rhabdias nematodes as most common gastrointestinal parasites in captive snakes of German households and zoological gardens

Nowadays, snakes established as domestic exotic pets, harboring numerous (zoonotic) gastrointestinal parasites. In this parasitological survey, we used direct saline fecal smears (DSFS) to examine 586 stool samples from 71 different snake species either kept as pets in households or in zoological gardens in Germany. In addition to DSFS, carbol-fuchsin-fecal smears (n = 296), coproantigen ELISA tests (n = 98), and immunofluorescence assays (IFA; n = 77) for the detection reptile Cryptosporidium infections were conducted. Complete dissections of deceased snakes (n = 63) were also performed in order to gain data on endoparasite species burdens affecting domestic snakes. Overall, examined fecal samples contained 20 different parasite taxa: Ancylostomatid Kalicephalus spp. were the most prevalent nematode species (3.3%), followed by Strongyloides/Rhabdias (2.6%), flagellated protozoan trophozoites (e. g., Proteromonadida, Reteromonadida) (2.3%), Monocercomonas spp. (1.9%), Entamoeba spp. (1.4%), unsporulated coccidian oocysts (1.4%), Kapsulotaenia spp. (0.9%), Capillaria spp. (0.7%), indet. trematodes (0.5%), pentastomids (0.5%), spirurids (0.4%), Eimeria spp. (0.4%), ascarids (0.4%), Blastocystis sp. (0.2%), heterakids (0.2%), cestodes (Proteocephalidae) (0.2%), Plagiorchis spp. (0.2%), Cryptosporidium spp. (0.2%), Caryospora epicratesi (0.2%), and Sarcocystis spp. (0.2%). For Cryptosporidium, four carbol-fuchsin-stained smears (1.4%), 12 (12.2%) coproantigen ELISA-examined samples and 5.2% of examined samples were diagnosed with IFA. Fourteen (22.2%) of dissected snakes showed infections with various pathogenic nematode genera and 8 of them (12.7%) died due to protozoan parasitic infections. High prevalences of intestinal protozoan parasites resulting in severe pathological findings observed in dissected snakes call for more detailed investigations on gastrointestinal parasites.

Captive Agamid lizards in Germany: Prevalence, pathogenicity and therapy of gastrointestinal protozoan and helminth infections

Reptiles are becoming popular pets in many parts of the world. They are also known to harbor numerous gastrointestinal parasites. We used faecal smears to examine 748 stool samples from 14 different agamid lizard species. In addition, we used coproantigen ELISA tests (11 samples) and immunofluorescence assays (IFA) (19 samples) to detect reptile Cryptosporidium infections. In 28 cases, veterinarians requested therapy to treat oxyurid- and/or Isospora amphiboluri-infections and resent fecal samples after proposed therapy and anti-parasitic treatments had been applied. We also performed complete dissections of 24 deceased agamas in order to specify protozoan and helminth parasite infections. Overall, the examined fecal samples contained 6 different taxa. Oxyurids (Pharyngodonidae) were the most prevalent nematodes (41.2%), followed by I. amphiboluri (17.0%), Entamoeba spp. (0.8%), Choleoeimeria spp. (0.5%), Trichomonas spp. (0.3%), Cryptosporidium spp. (0.3%) and Strongyloides-like nematodes (0.1%). I. amphiboluri infections were significantly more prevalent (Chi-square test: χ² = 21,5, df = 1, P <  0.001) in juvenile agamid lizards (31.9%) than in adults (14.2%). One of 11 (9.1%) coproantigen ELISA-examined samples was positive for Cryptosporidium. In 10.5% of the samples we found oocysts of Cryptosporidium. Thirteen (54.2%) of necropsied agamid lizards were infected with endoparasites and it is likely that three (12.5%) of them died due to severe parasitic infections. 74.0% of the samples that were submitted after therapy had been applied were negative. The high prevalences and pathological findings of several clinical parasitoses observed in these exotic reptiles calls for more detailed investigations on agamid gastrointestinal parasite fauna.

Follow-up study of high-dose praziquantel therapy for cerebral sparganosis

Background

Cerebral sparganosis is the most serious complication of human sparganosis. Currently, there is no standard for the treatment of inoperable patients. Conventional-dose praziquantel therapy is the most reported treatment. However, the therapeutic outcomes are not very effective. High-dose praziquantel therapy is a useful therapeutic choice for many parasitic diseases that is well tolerated by patients, but it has not been sufficiently evaluated for cerebral sparganosis. This study aims to observe the prognoses following high-dose praziquantel therapy in inoperable patients and the roles of MRI and peripheral eosinophil absolute counts during follow-up.

Methodology

Baseline and follow-up epidemiological, clinical, radiological and therapeutic data related to 10 inoperable patients with cerebral sparganosis that were treated with repeated courses of high-dose praziquantel therapy, with each course consisting of 25 mg/kg thrice daily for 10 days were assessed, followed by analyses of the prognoses, MRI findings and peripheral eosinophil absolute counts.

Principal findings

Baseline clinical data: the clinical symptoms recorded included seizures, hemiparesis, headache, vomiting and altered mental status. Peripheral blood eosinophilia was found in 3 patients. The baseline radiological findings were as follows. Motile lesions were observed in 10 patients, including aggregated ring-like enhancements, tunnel signs, serpiginous and irregular enhancements. Nine of the 10 patients had varying degrees of white matter degeneration, cortical atrophy and ipsilateral ventricle dilation. The follow-up clinical data were as follows. Clinical symptom relief was found in 8 patients, symptoms were eliminated in 1 patient, and symptoms showed no change from baseline in 1 patient. Peripheral blood eosinophilia was found in 2 patients. The follow-up radiological findings were as follows. Motile lesions that were transformed into stable, chronic lesions were found in 8 patients, and motile lesions that were eliminated completely were found in 2 patients.

Conclusions

High-dose praziquantel therapy for cerebral sparganosis is effective. The radiological outcomes of motile lesions are an important indicator during the treatment process, especially during follow-ups after clinical symptoms have improved. Peripheral eosinophil absolute counts cannot be used as an effective prognostic indicator.

Sparganosis is a rare parasitic disease with a high prevalence in East Asia. Because of limited radiological technology and clinical experience, the prevalence of cerebral sparganosis is likely underestimated in developing countries. Cerebral sparganosis is the most serious complication of human sparganosis. Currently, it is generally believed that the most effective treatment for cerebral sparganosis is surgical treatment. However, the choice of treatment is a challenge for inoperable patients, including those with multifocal lesions or lesions in deep structures or important functional areas and those refusing invasive treatment due to personal willingness. Currently, there is no standard for the treatment of inoperable patients. In addition, anthelmintic treatment for sparganosis has rarely been reported in the literature. High-dose praziquantel therapy is a useful therapeutic choice for many cerebral parasitic diseases, including neurocysticercosis, and is well tolerated for patients, but it has not been sufficiently evaluated for the treatment of cerebral sparganosis. This study aims to describe the clinical, radiological and therapeutic data following high-dose praziquantel therapy for ten inoperable patients. All patients reached clinical cure after one to five courses. These results suggest that high-dose praziquantel therapy for cerebral sparganosis could achieve favorable outcomes and that MRI plays an important role in follow-up, especially when clinical symptoms have improved.

Occurrence of health-compromising protozoan and helminth infections in tortoises kept as pet animals in Germany

BACKGROUND

Exotic reptiles such as tortoises, have become increasingly common domestic pets worldwide and are known to host different gastrointestinal parasites. Some of these parasites bear zoonotic potential. In the present survey, we parasitologically examined tortoise faecal samples (n = 1005) from 19 different species held as pets in private German households and German zoological gardens.

METHODS

Saline faecal smears were used to generate prevalence data for potentially health-compromising gastrointestinal parasites. In addition, we performed complete parasitological dissections of dead tortoises (n = 49) to estimate endoparasite burdens precisely.

RESULTS

Analysed tortoise faecal samples contained a broad spectrum of endoparasites. We detected ten taxa of endoparasites; oxyurid nematodes (e.g. Tachygonetria spp.) were the most prevalent parasites in faecal samples (43.18%), followed by ascarids (Angusticaecum spp.) (0.01%), Hexamita spp. (0.007%), Balantidium spp. (0.007%), trichomonads (0.004%), Strongyloides spp. (0.003%), Entamoeba spp. (0.005%), Hartmanella spp. (0.001%), Blastocystis spp. (0.002%), heterakids (0.001%) and Trimitus spp. (0.001%). Additionally, we investigated dead tortoise individuals (n = 49; of 10 different species) for aetiological diagnosis and estimation of endoparasite burden. Of these individuals, 38 (77.6%) were infected with parasites and 14 (28.6%) of them died most probably due to severe parasitic infection. Oxyurid infections correlated positively with calcium deficiency and metabolic bone disease (MBD) as well as nephrosis/nephritis, mainly occurring in juvenile tortoises (< 5 years of age).

CONCLUSIONS

The saline faecal smear technique proved to be efficient in detecting different metazoan and protozoan parasite stages in tortoise faeces. The prevalence of oxyurid infections was particularly high. In combination with pathological findings in clinical oxyuridosis obtained from necropsied animals, our findings call for further, detailed investigations on pathogenesis and immunology of oxyurids in pet reptiles. Coprological analyses for parasite detection should be mandatory before tortoises are transferred to a new owner, animal group, or public and private enclosures such as zoos. We advocate for regular health screenings in pet tortoises and, if parasitic infections are diagnosed, adequate medication or alternative hygiene management should be considered to improve and maintain individual and population health.

Orbital sparganosis in an 8-year boy: a case report

Background

Sparganosis is one of the neglected but important food-borne parasitic zoonoses, with higher prevalence in Asian countries. The infection is commonly located in the subcutaneous tissue, brain, breast, and lung, but fewer reported infections involve the eye. Because the majority of patients with sparganosis are adults, it is likely to be missed in children.

Case presentation

An 8-year-old boy presented to our clinic complaining of a painless ocular mass in his right eye for 1 month. The boy had a history of eating frogs and frog poultice applications to his eyelids. The patient was checked for an elliptical mass near the medial wall of the right eye. Serodiagnosis testing was positive in an enzyme-linked immunosorbent assay. During surgical operation on the patient, calcified parasite eggs and foreign body granulomatous reaction were found using histological examination. Due to early detection and surgery, the patient fully recovered with no damage to his eyesight.

Conclusions

Although rare, ocular sparganosis should be suspected in a mass of the eye when there is a history of eating frogs and frog poultice applications on eyelids. Early surgical resection is important for a good prognosis.

Electronic supplementary material

The online version of this article (10.1186/s12886-018-0675-8) contains supplementary material, which is available to authorized users.

A waterborn zoonotic helminthiase in an Italian diver: a case report of a cutaneous Sparganum infection and a review of European cases

Many waterborne helminthes are opportunistic parasites that can travel directly from animals to man and may contain forms capable of penetrating the skin. Among these, Sparganum is the pseudophyllidean tapeworm that belongs to the genus Spirometra, which is responsible for parasitic zoonosis; it is rarely detected in Europe and is caused by the plerocercoid infective larva. Thus far, only six cases of cutaneous and ocular sparganosis have been reported in Europe; two and four cases have occurred in France and Italy, respectively. Herein, we describe a new case of sparganosis in Italy that affected a male diver who presented to the Bambino Gesù Children's Hospital of Rome. The patient's skin biopsy was submitted to the Parasitology department who, in consultation with Pathology, concluded that the morphologic and microscopic findings were those of Sparganum spp. larvae. The patient recovered following a single dose of 600 mg praziquantel.

The genome of the sparganosis tapeworm Spirometra erinaceieuropaei isolated from the biopsy of a migrating brain lesion

BACKGROUND

Sparganosis is an infection with a larval Diphyllobothriidea tapeworm. From a rare cerebral case presented at a clinic in the UK, DNA was recovered from a biopsy sample and used to determine the causative species as Spirometra erinaceieuropaei through sequencing of the cox1 gene. From the same DNA, we have produced a draft genome, the first of its kind for this species, and used it to perform a comparative genomics analysis and to investigate known and potential tapeworm drug targets in this tapeworm.

RESULTS

The 1.26 Gb draft genome of S. erinaceieuropaei is currently the largest reported for any flatworm. Through investigation of β-tubulin genes, we predict that S. erinaceieuropaei larvae are insensitive to the tapeworm drug albendazole. We find that many putative tapeworm drug targets are also present in S. erinaceieuropaei, allowing possible cross application of new drugs. In comparison to other sequenced tapeworm species we observe expansion of protease classes, and of Kuntiz-type protease inhibitors. Expanded gene families in this tapeworm also include those that are involved in processes that add post-translational diversity to the protein landscape, intracellular transport, transcriptional regulation and detoxification.

CONCLUSIONS

The S. erinaceieuropaei genome begins to give us insight into an order of tapeworms previously uncharacterized at the genome-wide level. From a single clinical case we have begun to sketch a picture of the characteristics of these organisms. Finally, our work represents a significant technological achievement as we present a draft genome sequence of a rare tapeworm, and from a small amount of starting material.

Diagnosis of gastrointestinal parasites in reptiles: comparison of two coprological methods

Background

Exotic reptiles have become increasingly common domestic pets worldwide and are well known to be carriers of different parasites including some with zoonotic potential. The need of accurate diagnosis of gastrointestinal endoparasite infections in domestic reptiles is therefore essential, not only for the well-being of captive reptiles but also for the owners. Here, two different approaches for the detection of parasite stages in reptile faeces were compared: a combination of native and iodine stained direct smears together with a flotation technique (CNF) versus the standard SAF-method.

Results

A total of 59 different reptile faeces (20 lizards, 22 snakes, 17 tortoises) were coprologically analyzed by the two methods for the presence of endoparasites. Analyzed reptile faecal samples contained a broad spectrum of parasites (total occurence 93.2%, n = 55) including different species of nematodes (55.9%, n = 33), trematodes (15.3%, n = 9), pentastomids (3.4%, n = 2) and protozoans (47.5%, n = 28). Associations between the performances of both methods to detect selected single parasite stages or groups of such were evaluated by Fisher's exact test and marginal homogeneity was tested by the McNemar test. In 88.1% of all examined samples (n = 52, 95% confidence interval [CI] = 77.1 - 95.1%) the two diagnostic methods rendered differing results, and the McNemar test for paired observations showed highly significant differences of the detection frequency (P < 0.0001).

Conclusion

The combination of direct smears/flotation proved superior in the detection of flagellates trophozoites, coccidian oocysts and nematode eggs, especially those of oxyurids. SAF-technique was superior in detecting larval stages and trematode eggs, but this advantage failed to be statistically significant (P = 0.13). Therefore, CNF is the recommended method for routine faecal examination of captive reptiles while the SAF-technique is advisable as additional measure particularly for wild caught animals and individuals which are to be introduced into captive collections.

The genome of the sparganosis tapeworm Spirometra erinaceieuropaei isolated from the biopsy of a migrating brain lesion

BACKGROUND

Sparganosis is an infection with a larval Diphyllobothriidea tapeworm. From a rare cerebral case presented at a clinic in the UK, DNA was recovered from a biopsy sample and used to determine the causative species as Spirometra erinaceieuropaei through sequencing of the cox1 gene. From the same DNA, we have produced a draft genome, the first of its kind for this species, and used it to perform a comparative genomics analysis and to investigate known and potential tapeworm drug targets in this tapeworm.

RESULTS

The 1.26 Gb draft genome of S. erinaceieuropaei is currently the largest reported for any flatworm. Through investigation of β-tubulin genes, we predict that S. erinaceieuropaei larvae are insensitive to the tapeworm drug albendazole. We find that many putative tapeworm drug targets are also present in S. erinaceieuropaei, allowing possible cross application of new drugs. In comparison to other sequenced tapeworm species we observe expansion of protease classes, and of Kuntiz-type protease inhibitors. Expanded gene families in this tapeworm also include those that are involved in processes that add post-translational diversity to the protein landscape, intracellular transport, transcriptional regulation and detoxification.

CONCLUSIONS

The S. erinaceieuropaei genome begins to give us insight into an order of tapeworms previously uncharacterized at the genome-wide level. From a single clinical case we have begun to sketch a picture of the characteristics of these organisms. Finally, our work represents a significant technological achievement as we present a draft genome sequence of a rare tapeworm, and from a small amount of starting material.

Magnetic resonance imaging features of pathologically proven cerebral sparganosis

Objective

The purpose of this study was to identify characteristic magnetic resonance imaging (MRI) features of cerebral sparganosis, a rare parasitic disease caused by the plerocercoid larva of Spirometra mansoni.

Methods

This retrospective study reviewed medical records, computed tomography (CT) and MRI scans and pathological specimens from patients with pathologically proven cerebral sparganosis. The location, signal intensity and contrast enhancement characteristics of the lesions were assessed.

Results

Records of 12 patients (seven male and five female; age range 8–35 years) were reviewed. A total of 13 lesions were identified: of the 10 patients with supratentorial lesions, nine had a single lesion and one had bilateral hemispheric lesions. Two patients had a single lesion in the ependyma of the 4th ventricle. All lesions were iso-hypointense on T1-weighted images, slightly hypointense on T2-weighted images and surrounded by extensive oedema. Ten of the 13 lesions demonstrated a ‘string-knots sign’, characterized by a tangled string in a knot-like shape on contrast-enhanced MRI.

Conclusion

A string-knots sign enhancement pattern in cortical–subcortical regions should suggest the diagnosis of cerebral sparganosis.