Neurocognitive and neuropsychiatric effects of toxocariasis.

Caused by the neuroinvasive nematodes Toxocara canis and Toxocara cati, human toxocariasis has a worldwide distribution with seroprevalence in humans associated with low socioeconomic status and low educational attainment. Third-stage Toxocara larvae can invade human tissues, including the brain and spine, where they can result in encephalitis, meningitis, and inflammation. Toxocara infection in animal models has been associated with cognitive and behavioural changes. In humans, preliminary cross-sectional research suggests that Toxocara seropositivity is associated with worse cognitive function in children and adults. Additional preliminary cross-sectional findings suggest associations between Toxocara seropositivity and neuropsychiatric function, including schizophrenia and neurologic conditions such as epilepsy. Given the widespread distribution of human toxocariasis and early evidence suggesting that it can be associated with cognitive and neuropsychiatric function in humans, additional research regarding the effects of toxocariasis on the human brain is required.

[Cerebral hydatid cyst: Clinical case and review of the literature]. / Quiste hidatídico cerebral: caso clínico y revisión de la literatura.

Hydatid disease is an accidental parasitosis, with brain location being rare. The case is reported of a 33year-old male, with no history of note, who was admitted to hospital with intracranial hypertension syndrome and right hemiparesis. Computed tomography showed a cystic lesion in the left frontal-parietal lobule. Surgery was performed by complete excision of the lesion, with a good outcome. Hydatid disease is a rare condition in the brain. Clinical suspicion is important for an early diagnosis. A review is presented on the pathogenesis, diagnosis and treatment of cerebral hydatid disease.

Parasitic diseases of the central nervous system: lessons for clinicians and policy makers.

Parasitic diseases of the central nervous system are associated with high mortality and morbidity, especially in resource-limited settings. The burden of these diseases is amplified as survivors are often left with neurologic sequelae affecting mobility, sensory organs, and cognitive functions, as well as seizures/epilepsy. These diseases inflict suffering by causing lifelong disabilities, reducing economic productivity, and causing social stigma. The complexity of parasitic life cycles and geographic specificities, as well as overlapping clinical manifestations in the host reflecting the diverse pathogenesis of parasites, can present diagnostic challenges. We herein provide an overview of these parasitic diseases and summarize clinical aspects, diagnosis, therapeutic strategies and recent milestones, and aspects related to prevention and control.

Cerebral paragonimiasis: an unusual manifestation of a rare parasitic infection.

BACKGROUND: Paragonimiasis is a parasitic disease that typically produces a subacute to chronic inflammatory disease of the lung. Although rare in the United States, paragonimiasis is sporadically observed in the immigrant population. Rarely, paragonimiasis can affect the nervous system. This infection is even more unusual in the pediatric population, and therefore can be challenging to diagnose. PATIENTS: Here we present a child with cerebral paragonimiasis. She presented with new onset seizures in the setting of a febrile illness. Magnetic resonance imaging of the brain with contrast revealed a ring-enhancing lesion within the right frontal lobe and a second lesion in the left parietal lobe extending from the cortex to the centrum semiovale. Extensive evaluation including stool ova and parasite analysis confirmed the diagnosis of Paragonimus westermani. She was treated with praziquantel and prednisone and improved both clinically and radiographically. CONCLUSIONS: Cerebral paragonimiasis is diagnosable and treatable and therefore is important to consider in the differential of immigrants presenting with cavitary lung lesions and central nervous system findings.

Cerebral paragonimiasis: a retrospective analysis of 27 cases.

OBJECT: The authors retrospectively analyzed the clinical characteristics, existing problems, and treatment experiences in recently diagnosed cerebral paragonimiasis (CP) cases and sought to raise awareness of CP and to supply reference data for early diagnosis and treatment. METHODS: Twenty-seven patients (22 male and 5 female; median age 20.3 years, range 4-47 years) with CP were diagnosed between September 2008 and September 2013. These diagnoses were confirmed by IgG enzyme-linked immunosorbent assays. Follow-up was performed in 24 cases for a period of 6-56 months. RESULTS: Cerebral paragonimiasis accounted for 21.6% of paragonimiasis cases (27 of 125). The average duration from onset to praziquantel treatment was 69 days. All patients resided in rural areas. Twenty patients had positive lung results, which included visible lung lesions in 14 cases. The lesions were surgically removed in 8 of these cases. Twenty-four patients had high eosinophil counts (≥ 0.08 × 10(9)/L), and eosinophilic meningitis was noted in 17 cases. The rate of misdiagnosis and missed diagnosis was 30.4%. Most symptoms were markedly improved after treatment, but mild movement disorders combined with impaired memory and personality changes remained in a small number of patients. CONCLUSIONS: Clinicians should be alert to the possibility of CP in young patients (4-16 years) with the primary symptoms of epilepsy and hemorrhage. Early diagnosis and timely treatment can reduce the need for surgery and further impairments to brain function. Liquid-based cytological examination of CSF and peripheral blood eosinophil counts can aid in differentiating CP from similar lesions.

Paragonimiasis.

Human paragonimiasis is caused by nine species of Paragonimus, namely, P. westermani, P. africanus, P. heterotremus, P. kellicotti, P. mexicanus, P. siamensis, P. skrjabini, P. skrjabini miyazakii, and P. uterobilateralis. Cerebral or spinal involvements are most common in P. westermani, and can also occur in P. skrjabini, P. skrjabini miyazakii, and P. mexicanus. In P. westermani, cerebral paragonimiasis comprises about 45% of all extrapulmonary paragonimiasis cases, and accounts for about 1% of all paragonimiasis patients. In cerebral paragonimiasis, seizure, headache, visual disturbance, and motor and sensory disturbances are the five major clinical symptoms. The most commonly performed diagnostic procedures for cerebral infections are serological tests to detect circulating antibodies or antigens using ELISA or immunoblotting, and radiological examinations, including plain skull x-rays, brain CT, and MR scans. The drug of choice is praziquantel at the dose of 25mg/kg three times daily for 2-3 days. In severe infections, a second set of treatment may be needed. Triclabendazole can be used in P. uterobilateralis, P. mexicanus, and P. skrjabini infections with the dose of 10mg/kg twice a day; however, its efficacy in P. westermani infection, in particular cerebral infections, remains to be elucidated.

Babesia lengau associated with cerebral and haemolytic babesiosis in two domestic cats.

BACKGROUND: Although reported sporadically from various countries, feline babesiosis appears to be a significant clinical entity only in South Africa, where Babesia felis is usually incriminated as the causative agent. Babesia lengau, recently described from asymptomatic cheetahs, has now possibly been incriminated as the causative agent in two severe clinical cases in domestic cats. FINDINGS: Both cats were euthanised in extremis. While typical feline babesiosis in South Africa is an afebrile disease with a chronic manifestation, there was acute onset of severe clinical signs in both cats and their body temperatures were above the normal range when they were presented for treatment. Haemolytic anaemia was confirmed in one case. To our knowledge, this is the first report of cerebral babesiosis in cats.On reverse line blot 18S rDNA PCR products obtained from both cats showed positive hybridization profiles with the B. lengau species-specific probe. The two partial parasite 18S rRNA gene sequences obtained, showed high sequence similarity (99.9%) to B. lengau. In a representative tree constructed by the neighbor-joining method using the two-parameter model of Kimura the two obtained partial 18S rDNA sequences and that of B. lengau formed a monophyletic group with B. conradae and sequences previously isolated from humans and wildlife in the western USA. CONCLUSION: All clinical cases of feline babesiosis in South Africa are not necessarily caused by B. felis. Other piroplasms, e.g. B. lengau, may be incriminated in clinical cases, especially those occurring outside the known endemic area.

Presumptive central nervous system cuterebriasis and concurrent protein-losing nephropathy in a dog.

OBJECTIVE: To describe the clinical course and successful management of a dog suspected to have central nervous system (CNS) Cuterebra larval migration and concurrent protein-losing nephropathy (PLN). CASE SUMMARY: A 1-year-old castrated male mixed breed dog was diagnosed with presumptive CNS cuterebriasis based on history, progressively deteriorating mentation, seizures, and magnetic resonance images showing a tubular lesion consistent with a migrating Cuterebra tract. Additionally, serum biochemistry and urine analyses revealed the development of a severe PLN. Surgical removal of the Cuterebra was attempted unsuccessfully, and subsequently, the dog was treated with ivermectin, antihistamines, anticonvulsants, and a tapering dose of glucocorticoids. Over several weeks the dog's neurologic status improved and the PLN resolved completely. NEW OR UNIQUE INFORMATION PROVIDED: This case describes successful management of presumptive CNS cuterebriasis in a dog. It is also, to our knowledge, the first report of PLN associated with cuterebriasis in the veterinary literature.

Spine infections.

Infections of the spine represent a rare but potentially debilitating and neurologically devastating condition for patients. Early diagnosis, imaging, and intervention may prevent some of the more critical complications that may ensue from this disease process, including alignment abnormalities, central canal compromise, nerve root impingement, vascular complications, and spinal cord injury. This article reviews the underlying pathophysiologic basis of infection, clinical manifestations, and imaging modalities used to diagnose infections of the spine and spinal cord.

Alzheimer's disease - a neurospirochetosis. Analysis of the evidence following Koch's and Hill's criteria.

It is established that chronic spirochetal infection can cause slowly progressive dementia, brain atrophy and amyloid deposition in late neurosyphilis. Recently it has been suggested that various types of spirochetes, in an analogous way to Treponema pallidum, could cause dementia and may be involved in the pathogenesis of Alzheimer's disease (AD). Here, we review all data available in the literature on the detection of spirochetes in AD and critically analyze the association and causal relationship between spirochetes and AD following established criteria of Koch and Hill. The results show a statistically significant association between spirochetes and AD (P = 1.5 × 10-17, OR = 20, 95% CI = 8-60, N = 247). When neutral techniques recognizing all types of spirochetes were used, or the highly prevalent periodontal pathogen Treponemas were analyzed, spirochetes were observed in the brain in more than 90% of AD cases. Borrelia burgdorferi was detected in the brain in 25.3% of AD cases analyzed and was 13 times more frequent in AD compared to controls. Periodontal pathogen Treponemas (T. pectinovorum, T. amylovorum, T. lecithinolyticum, T. maltophilum, T. medium, T. socranskii) and Borrelia burgdorferi were detected using species specific PCR and antibodies. Importantly, co-infection with several spirochetes occurs in AD. The pathological and biological hallmarks of AD were reproduced in vitro by exposure of mammalian cells to spirochetes. The analysis of reviewed data following Koch's and Hill's postulates shows a probable causal relationship between neurospirochetosis and AD. Persisting inflammation and amyloid deposition initiated and sustained by chronic spirochetal infection form together with the various hypotheses suggested to play a role in the pathogenesis of AD a comprehensive entity. As suggested by Hill, once the probability of a causal relationship is established prompt action is needed. Support and attention should be given to this field of AD research. Spirochetal infection occurs years or decades before the manifestation of dementia. As adequate antibiotic and anti-inflammatory therapies are available, as in syphilis, one might prevent and eradicate dementia.

Dental management of the tropical disease human African trypanosomiasis: an unusual case of pseudobulbar palsy.

Human African trypanosomiasis (sleeping sickness) is a parasitic tropical disease endemic to sub-Saharan Africa. Due to migration and holiday travel patterns cases are increasing in the United Kingdom. The neurological sequelae have dental management implications both directly from the consequent physical disability and indirectly from the oral side-effects of the medications used to manage symptoms. Changes in disease demographics require the dental profession to increase its awareness of migration medicine and the appropriate dental management of such diseases.

Onchocerciasis-related epilepsy? Prospects at a time of uncertainty.

Epilepsy and onchocerciasis (river blindness) constitute serious public health problems in several tropical countries. There are four main mechanisms that might explain a relationship between these two diseases: (i) the presence of Onchocerca volvulus in the central nervous system; (ii) the pathogenicity of various O. volvulus strains; (iii) immunological mechanisms involving cross-reactive immunization or cytokine production during infection; and (iv) the triggering role of insomnia due to itching.

Ophthalmomyiasis (interna posterior) of the posterior segment and central nervous system myiasis: Cuterebra spp. in a cat.

A unilateral ophthalmomyiasis posterior in a 5-year-old female spayed Domestic Long-haired cat of a third or fourth stage instar Cuterebra spp. larvae is reported. The cat was presented for depression and anorexia. The organism was found on physical examination at presentation. The cat was euthanized because of the worsening systemic condition. The larva was demonstrated by histopathology with coagulation necrosis and hemorrhage of the optic nerve, retina and choroid, and anterior uveitis. No significant cerebrum and anterior brain stem lesions were found.

Chronic cerebral paragonimiasis combined with aneurysmal subarachnoid hemorrhage.

A 67-year-old Korean woman attended our hospital complaining of a severe headache. A brain computed tomography scan showed conglomerated, high-density, calcified nodules in the left temporo-occipito-parietal area and high-density subarachnoid hemorrhage in the basal cisterns. Magnetic resonance imaging of the brain shows multiple conglomerated iso- or low-signal intensity round nodules with peripheral rim enhancement. She underwent craniotomies to clip the aneurysm and remove the calcified masses. Paragonimus westermani eggs were identified in the calcified necrotic lesions. Results of parasitic examinations on the sputum and an enzyme-linked immunosorbent assay for P. westermani were all negative. The patient presented with headache and dizziness that had occurred for more than 30 years. She had not eaten freshwater crayfish or crabs. However, she had sometimes prepared raw crabs for several decades. Overall, this case was diagnosed as chronic cerebral paragonimiasis, in which she may have been infected through the contamination of utensils during the preparation of the second intermediate hosts, combined with a cerebral hemorrhage.

Submandibular and intracranial hydatid cyst in an adolescent.

OBJECTIVES: An unusual case of hydatid disease is reported. Review of the pertinent literature did not reveal any hydatid disease located simultaneously in both the intracranial and submandibular glands. This is the first case with hydatid disease occurring in both locations at the same time. STUDY DESIGN: The case of an 18-year-old is presented; the symptoms, findings, methods of diagnosis, and our approach for treatment are discussed; and the literature is reviewed. RESULTS: The intracranial lesion was completely excised by left-sided frontoparietal craniotomy, and the mass in the right side of the submandibular gland was removed through a submandibular approach at the same session. The intact cyst was completely excised. Histological examination of both lesions confirmed the diagnosis of hydatid cyst by. Postoperative recovery was uneventful, and the patient was discharged on the seventh day. CONCLUSIONS: Hydatid cyst should be suspected during the evaluation of cervical masses, particularly in endemic regions. Hydatid disease infestations are best treated with complete excision of the intact cyst.

Infectious myelopathies.

Although infectious myelopathies are rare, timely and accurate diagnosis is essential to improving outcome. There are a number of organisms that may cause infectious myelopathies, including human immunodeficiency virus (HIV), human T-cell lymphotropic virus type I (HTLV-I), herpesviruses, enteroviruses, Treponema pallidum, Mycobacterium tuberculosis, fungi, and parasites. Vacuolar myelopathy, the most common form of spinal cord disease in HIV-infected individuals, is underrecognized clinically. The failure to diagnose this condition is generally a consequence of the attribution of the lower extremity weakness and paresthesias to general debility and concomitant peripheral neuropathy. Tropical spastic paraparesis or HTLV-I-associated myelopathy involves the pyramidal tracts, chiefly at the thoracic level, and results in spastic lower extremity weakness and a spastic bladder. The herpesviruses (varicella-zoster, herpes simplex type 2, cytomegalovirus) and the enteroviruses cause myelitis. Prior to the development of antibiotics, syphilis was the most frequent infectious cause of spinal cord disease. In light of the broad spectrum of pathogens that may affect the spinal cord and the variegate fashion in which these disorders may present, the physician must always consider an infectious etiology in the differential diagnosis for the patient presenting with myelopathy. This review addresses the infectious myelopathies by microorganism.

Clinics in diagnostic imaging (58). Chronic cerebral paragonimiasis.

A 36-year-old Korean man presented with a history of epilepsy. MR imaging of the brain revealed multiple conglomerated round nodules that were hypointense on both T1-and-T2 weighted images. These were located at the left temporal and occipital lobes and had surrounding encephalomalacia. CT scan confirmed the presence of large calcified nodules in the corresponding regions. These imaging findings were typical of chronic cerebral paragonimiasis. The clinical, CT and MR features of cerebral paragonimiasis are reviewed.