Cerebral sparganosis with intracerebral hemorrhage: a case report

Neuroimmunology of Common Parasitic Infections in Africa

Parasitic infections of the central nervous system are an important cause of morbidity and mortality in Africa. The neurological, cognitive, and psychiatric sequelae of these infections result from a complex interplay between the parasites and the host inflammatory response. Here we review some of the diseases caused by selected parasitic organisms known to infect the nervous system including Plasmodium falciparum, Toxoplasma gondii, Trypanosoma brucei spp., and Taenia solium species. For each parasite, we describe the geographical distribution, prevalence, life cycle, and typical clinical symptoms of infection and pathogenesis. We pay particular attention to how the parasites infect the brain and the interaction between each organism and the host immune system. We describe how an understanding of these processes may guide optimal diagnostic and therapeutic strategies to treat these disorders. Finally, we highlight current gaps in our understanding of disease pathophysiology and call for increased interrogation of these often-neglected disorders of the nervous system.

Multispecies reservoir of Spirometra erinaceieuropaei (Cestoda: Diphyllobothridae) in carnivore communities in north-eastern Poland

Background

Spirometra erinaceieuropaei is a diphylobothriid tapeworm with a complex life-cycle including definitive, intermediate and paratenic (transport) hosts. Multiple routes of parasite transmission often make it impossible to determine what type of host a specific infected animal is considered to be. Spargana larvae cause sparganosis, a severe food- and water-borne disease mainly found in Asia. In Poland, Spirometra sp. was reported in large carnivores in Białowieża Primeval Forest for the first time in the 1940s and was recently confirmed as S. erinaceieuropaei in several mammals and snakes using molecular methods.

Methods

In total, 583 carcasses of 9 carnivore species were necropsied between 2013 and 2019 in north-eastern (NE) Poland. The larvae of S. erinaceieuropaei (spargana) were isolated from subcutaneous tissue, counted, and preserved for genetic analyses. We calculated the prevalence and intensity of infection. To assess spatial variation in S. erinaceieuropaei infection probability in NE Poland, we applied a generalized additive model (GAM) with binomial error distribution. To confirm the species affiliation of isolated larvae, we amplified a partial fragment of the 18S rRNA gene (240 bp in length).

Results

Spirometra larvae were found in the subcutaneous tissue of 172 animals of 7 species and confirmed genetically as S. erinaceieuropaei. The overall prevalence in all studied hosts was 29.5% with a mean infection intensity of 14.1 ± 33.8 larvae per individual. Native European badgers and invasive raccoon dogs were characterized by the highest prevalence. An analysis of parasite spread showed a spatially diversified probability of infection with the highest values occurring in the biodiversity hot spot, Białowieża Primeval Forest.

Conclusions

Our study revealed that various mammal species (both native and non-native) can serve as S. erinaceieuropaei reservoirs. The frequency and level of infection may differ between selected hosts and likely depend on host diversity and habitat structure in a given area. Further studies are needed to assess the distribution of the parasite throughout Europe and the environmental and biological factors influencing infection severity in wild mammals.

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.

Human sparganosis, a neglected food borne zoonosis

Human sparganosis is a food borne zoonosis caused by the plerocercoid larvae (spargana) of various diphyllobothroid tapeworms of the genus Spirometra. Human infections are acquired by ingesting the raw or undercooked meat of snakes or frogs, drinking untreated water, or using raw flesh in traditional poultices. More than 1600 cases of sparganosis have been documented worldwide, mostly in east and southeast Asia. Sporadic cases have been reported in South America, Europe, and Africa, and several cases have been described in travellers returning from endemic regions. Epidemiological data suggest that the increased effect of sparganosis on human health is because of greater consumption of raw meat of freshwater frogs and snakes. This Review provides information about the Spirometra parasites and their lifecycles, summarises clinical features, diagnosis, and treatment of human sparganosis, and describes geographical distribution and infection characteristics of Spirometra parasites in host animals.

Angiographic findings in 2 children with cerebral paragonimiasis with hemorrhage

Hemorrhagic events associated with cerebral paragonimiasis are not rare, especially in children and adolescents; however, angiographic evidence of cerebrovascular involvement has not been reported. The authors describe angiographic abnormalities of the cerebral arteries seen in 2 children in whom cerebral paragonimiasis was associated with hemorrhagic stroke. The patients presented with acute intracerebral and subarachnoid hemorrhage. Angiography revealed a beaded appearance and long segmental narrowing of arteries, consistent with arteritis. In both patients, involved vessels were seen in the area of the hemorrhage. The vascular changes and the hemorrhage, together with new lesions that developed close to the hemorrhage and improved after praziquantel treatment, were attributed to paragonimiasis. Further study of the frequency and mechanism of hemorrhagic cerebrovascular complications associated with cerebral paragonimiasis is needed.

Parasitoses of the human central nervous system

Cerebral involvement in parasitoses is an important clinical manifestation of most of the human parasitoses. Parasites that have been described to affect the central nervous system (CNS), either as the dominant or as a collateral feature, include cestodes (Taenia solium (neurocysticerciasis), Echinococcus granulosus (cerebral cystic echinococcosis), E. multilocularis (cerebral alveolar echinococcosis), Spirometra mansoni (neurosparganosis)), nematodes (Toxocara canis and T. cati (neurotoxocariasis), Trichinella spiralis (neurotrichinelliasis), Angiostrongylus cantonensis and A. costaricensis (neuroangiostrongyliasis), Gnathostoma spinigerum (gnathostomiasis)), trematodes (Schistosoma mansoni (cerebral bilharziosis), Paragonimus westermani (neuroparagonimiasis)), or protozoa (Toxoplasma gondii (neurotoxoplasmosis), Acanthamoeba spp. or Balamuthia mandrillaris (granulomatous amoebic encephalitis), Naegleria (primary amoebic meningo-encephalitis), Entamoeba histolytica (brain abscess), Plasmodium falciparum (cerebral malaria), Trypanosoma brucei gambiense/rhodesiense (sleeping sickness) or Trypanosoma cruzi (cerebral Chagas disease)). Adults or larvae of helminths or protozoa enter the CNS and cause meningitis, encephalitis, ventriculitis, myelitis, ischaemic stroke, bleeding, venous thrombosis or cerebral abscess, clinically manifesting as headache, epilepsy, weakness, cognitive decline, impaired consciousness, confusion, coma or focal neurological deficits. Diagnosis of cerebral parasitoses is dependent on the causative agent. Available diagnostic tools include clinical presentation, blood tests (eosinophilia, plasmodia in blood smear, antibodies against the parasite), cerebrospinal fluid (CSF) investigations, imaging findings and occasionally cerebral biopsy. Treatment relies on drugs and sometimes surgery. Outcome of cerebral parasitoses is highly variable, depending on the effect of drugs, whether they are self-limiting (e.g. Angiostrongylus costaricensis) or whether they remain undetected or asymptomatic, like 25% of neurocysticerciasis cases.

CT and MR characteristics of cerebral sparganosis

BACKGROUND AND PURPOSE

Sparganosis is a rare parasitic infection in humans by a larval cestode of the genus Spirometra. Preoperative diagnosis of cerebral sparganosis in the past has been very difficult. Our objective was to evaluate the CT and MR features of cerebral sparganosis in order to make a definite diagnosis.

MATERIALS AND METHODS

We retrospectively reviewed 25 patients (13 male and 12 female; age range, 9-83 years) who proved to have cerebral sparganosis. Fifteen patients underwent MR imaging: 2 patients had CT scanning, and the remaining 8 had both CT and MR scanning. We focused on evaluating the imaging features on CT and MR.

RESULTS

All patients showed edema and degeneration of cerebral white matter. All but 1 had a unilateral lesion. Twenty-two patients had ipsilateral ventricular dilation. The new finding was a tunnel sign, approximately 4 cm in length and 0.8 cm in width, column or fusiform shaped on postcontrast coronal and sagittal MR images (n = 10). Thirteen patients showed bead-like enhancement, but solitary ring enhancement was common on the CT images (n = 2). The wall of the ring and tunnel appeared isointense or slightly hyperintense on T2-weighted images. Punctate calcifications were seen in 6 patients on CT images but only in 3 patients on the MR images. Hemorrhage was seen in 4 patients on the MR images. An intact whitish, stringlike, living worm was found (n = 5).

CONCLUSION

The most characteristic finding was a tunnel sign on postcontrast MR images. The most common finding was bead-shaped enhancement. MR is superior to CT in demonstrating the extent and number of lesions, except punctate calcifications. Combined with clinical data and enzyme-linked immunosorbent assay, the preoperative diagnosis of cerebral sparganosis could be established on MR imaging.

Neuroimaging and pathological findings in a child with cerebral sparganosis

The authors report the case of a 6-year-old boy with cerebral sparganosis due to infection with a plerocercoid tapeworm larva of Spirometra mansoni. Magnetic resonance imaging revealed an area of irregular long T2 signal in the right frontal lobe. When compared with images obtained 2 years earlier, the lesion appeared to have migrated into the parietal lobe. During surgery for the removal of a granuloma, the parasite was discovered and excised. Following surgery, the patient's neurological deficits markedly improved. The authors review the pathological and imaging features of cerebral sparganosis.

Sparganum mansoni parasitic infection in the lung showing a nodule

Reported herein is a 57-year-old man infected by Sparganum mansoni, a kind of tapeworm, showing a solitary nodule of the middle lobe of the right lung. Because a transbronchial biopsy could not diagnose the nodule, a right middle lobectomy was performed on suspicion of malignant tumor. The lesion was diagnosed as sparganosis by histological and immuno-serological examinations. Histological examination revealed granulomatous inflammation with neutrophil and eosinophil infiltration around the worm and interstitial pneumonia surrounding the nodule. Moreover, vasculitis with foreign body giant cell was seen around the lesion. To the authors' knowledge this is the second case of sparganosis limited in the lung, and the current report presents the first detailed histological description of a pulmonary sparganosis case.

Surgical removal of a live worm by stereotactic targeting in cerebral sparganosis. Case report

A 64-year-old man presented with generalized tonic clonic convulsion followed by weakness of the right lower extremity. He had a medical history of hypertension, hyperlipidemia, and right cerebellar infarction. Computed tomography (CT) showed a small high density nodule with an enhanced perifocal low density area in the left occipital lobe. T1-weighted magnetic resonance (MR) imaging showed a ring-shaped and partial string-like nodule with enhancement by gadolinium. T2-weighted MR imaging showed the white matter of the left occipital lobe as high intensity. CT and MR imaging seemed to indicate metastatic brain tumors, although cortical atrophy and ventricular dilation were recognized. Left parietal craniotomy was performed under stereotactic targeting to obtain a definitive diagnosis. During manipulation at the center of the targeted lesion, a white, tape-like body was found and recognized to be a live worm. Serological testing revealed strong immunopositivity against Spirometra mansoni. The infection route in the present case was probably through eating raw chicken meat. Cerebral sparganosis is extremely rare but should be considered in the differential diagnosis of metastatic brain tumors, especially in endemic areas.

Neuroparasitic infections: cestodes, trematodes, and protozoans

Parasitic infection of the nervous system can produce a variety of symptoms and signs. Because symptoms of infection are often mild or nonspecific, diagnosis can be difficult. Familiarity with basic epidemiological characteristics and distinguishing radiographic findings can increase the likelihood of detection and proper treatment of parasitic infection of the nervous system. This article discusses the clinical presentation, diagnosis, and treatment for some of the more common infections of the nervous system caused by cestodes, trematodes and protozoans: Echinococcus spp., Spirometra spp. (sparganosis), Paragonimus spp., Schistosoma spp., Trypanosoma spp., Naegleria fowlerii, Acanthamoeba histolytica, and Balamuthia mandrillaris.

Tapeworms

Tapeworms are among the oldest afflictions of humans. They continue, even today, to be an important cause of morbidity and mortality, worldwide. Taenia saginata and Taenia solium infections are still common in many developing countries. Diphyllobothrium latum infections, are decreasing, but this tapeworm, transmitted to humans through the eating of raw salmon, can cause severe anemia. Hymenolepis and Dipylidium infections may occur to children. Hydatid disease is a common cause of morbidity, especially among immigrant groups from endemic areas of the Mediterranean; the liver is the most common site of a hydatid cyst. Although surgery has been the mainstay of therapy, drug therapy and percutaneous aspiration have been used more frequently in recent years. praziquantel and albendazole are the two most useful drugs against various tapeworm infections.