Parasitic infections of the central nervous system in children. Part II: Disseminated infections

Influence of L-carnitine supplementation on serum lipid profile in hemodialysis patients: a systematic review and meta-analysis

BACKGROUND/AIMS

An increasing body of evidence demonstrates that L-carnitine plays a pivotal role in lipid metabolism of hemodialysis (HD) patients. However, there are still some reservations about its benefits. Therefore, we performed a meta-analysis to assess the effects of L-carnitine supplementation on lipid profile in HD patients.

METHODS

Literature search was performed to identify the relevant randomized controlled trials that investigated the effects of L-carnitine on the lipid profile of subjects. Two independent authors used an Excel file to extract data and assess trials quality. The primary effect measure was the difference in means of the final lipid measurements between the intervention and control groups. The meta-analysis was performed with the fixed-effects model or random-effects model according to heterogeneity.

RESULTS

Twelve studies with a total of 391 patients met the inclusion criteria. The use of L-carnitine was not associated with a reduction in the total cholesterol (SMD, -0.11; 95% CI, -0.31 to 0.09), HDL-cholesterol (SMD, 0.01; 95% CI, -0.36 to 0.39), VLDL-cholesterol (SMD, 0.54; 95% CI, -0.06 to 1.14), and the serum triglycerides (SMD, -0.12; 95% CI, -0.36 to 0.12). However, L-carnitine can significantly decrease the LDL-cholesterol (SMD, -0.29; 95% CI, -0.53 to -0.06) in HD patients. In a subgroup meta-analysis, a significant LDL-cholesterol-lowering effect of L-carnitine supplementation was observed in intravenous application group, and patients with longer interventional duration and renal diseases.

CONCLUSION

The limited evidence suggests that there was no effect of L-carnitine on serum total cholesterol, HDL-cholesterol, VLDL-cholesterol and serum triglycerides. By contrast, this meta-analysis suggests a promising effect of L-carnitine on LDL-cholesterol. Further large-scale, well-designed randomized controlled trials are urgently needed

Neurological and ocular fascioliasis in humans

Fascioliasis is a food-borne parasitic disease caused by the trematode species Fasciola hepatica, distributed worldwide, and Fasciola gigantica, restricted to given regions of Africa and Asia. This disease in humans shows an increasing importance, which relies on its recent widespread emergence related to climate and global changes and also on its pathogenicity in the invasive, biliary, and advanced chronic phases in the human endemic areas, mainly of developing countries. In spite of the large neurological affection capacity of Fasciola, this important pathogenic aspect of the disease has been pronouncedly overlooked in the past decades and has not even appear within the numerous reviews on the parasitic diseases of the central nervous system. The aim of this wide retrospective review is an in-depth analysis of the characteristics of neurological and ocular fascioliasis caused by these two fasciolid species. The terms of neurofascioliasis and ophthalmofascioliasis are restricted to cases in which the direct affection of the central nervous system or the eye by a migrant ectopic fasciolid fluke is demonstrated by an aetiological diagnosis of recovered flukes after surgery or spontaneous moving-out of the fluke through the orbit. Cases in which the ectopic fluke is not recovered and the symptoms cannot be explained by an indirect affection at distance may also be included in these terms. Neurofascioliasis and ophthalmofascioliasis cases are reviewed and discussed. With regard to fascioliasis infection giving an indirect rise to neurological affection, the distribution and frequency of cases are analysed according to geography, sex, and age. Minor symptoms and major manifestations are discussed. Three main types of cases are distinguished depending on the characteristics of their manifestations: genuine neurological, meningeal, and psychiatric or neuropsychic. The impressive symptoms and signs appearing in each type of these cases are included. Brain examination techniques and neuroimaging useful for the diagnosis of neurological cases are exposed. Within fascioliasis infection indirectly causing ocular manifestations, case distribution and frequency are similarly analysed. A short analysis is devoted to clarify the first reports of a human eye infection. The affection of related and close organs is discussed by differentiating between cases of the dorsal spine, pulmonary manifestations, heart and vessel affection, findings in blood vessels, skin and dermatologic reactions, cases of ectopic mature flukes, and upper body locations. The clinical complexity of the puzzling polymorphisms, the disconcerting multifocality of the manifestations, and their changes along the evolution of the disease in the same patient, as well as the differences between the clinical pictures shown by different patients, are highlighted. The many syndromes involved are enumerated. The pathogenic and physiological mechanisms underlying neurofascioliasis and ophthalmofascioliasis caused by ectopic flukes and the physiopathogenic processes indirectly affecting the central nervous system and causing genuine neurological, meningeal, psychiatric, and ocular manifestations are discussed. The diagnosis of neurological and ophthalmologic fascioliasis is analysed in depth, including clinical and paraclinical diagnosis, eosinophilia in the blood and cerebrospinal fluid, differential diagnosis from other parasitic infections such as helminthiases and myiases, an update of human fascioliasis diagnosis, and fluke and/or fluke egg recovery by surgery. Diagnostic analyses with faecal and blood samples for fascioliasis patients are updated. Therapy for patients with major neurological manifestations includes both antiparasitic treatments and anti-inflammatory therapeutics. Prognosis in fascioliasis patients with neurological manifestations is discussed, with emphasis on sequelae and fatal cases, and the care of patients with ophthalmologic manifestations is added. Conclusions indicate that neurological cases are overlooked in human fascioliasis endemic areas and also in developing countries in general. In remote zones, rural health centres and small hospitals in or near the human endemic areas do not dispose of the appropriate equipments for neurological analyses. Moreover, physicians may not be aware about the potential relationship between liver fluke infection and neurological implications, and such cases may therefore remain misdiagnosed, even in developed countries. Priority should henceforth be given to the consideration of neurological and ocular affection in human endemic areas, and efforts should be implemented to assess their characteristics and frequency. Their impact should also be considered when estimating the global burden of fascioliasis.

Reviews on trichinellosis (II): neurological involvement

Neurological involvement may occur in 0.2%-52% of cases with trichinellosis, generally in the most severely affected patients. This review focuses on neurotrichinellosis and includes a brief overview of selected cases reported in the literature. Our primary goal was to increase the awareness of infectious diseases specialists, neurologists, and general practitioners about these major complications with possible fatal outcome. Seventy seven of the cases, for which enough details were available, have been pooled for statistical analysis. The mean age of the investigated group was 34.6 ± 16.8 years. Patients with both focal and diffuse manifestations predominated (55.8%), and they were significantly older (40 ± 15.5 years old) than those who presented solely focal (28.9 ± 17.8 years old; p = 0.03) or diffuse lesions (27.9 ± 15.3 years old; p = 0.007). In most of the cases (59.7%), complete recovery was reported, whereas 23.4% of cases had sequelae and 16.9% of the patients died. Patients who died had significantly lower eosinophil counts (13.8% ± 14%) when compared with those who made complete recovery (28.7% ± 18%; p = 0.015) and the cases with sequelae (35% ± 17.9%; p = 0.006). To sum up, trichinellosis must be considered in the differential diagnosis of any patient with encephalitis or other central nervous system malady of ambiguous etiology.

Shunt revision in hydrocephalus

OBJECTIVE

A retrospective analysis of 50 hydrocephalic children having a minimum follow-up of 6 months was carried out to see their etiology, clinical features, complications, incidence of shunt revisions, outcome and the variation from their Western counterparts.

METHODS

Clinical features, image findings and treatment of all the cases were recorded from their discharge summaries. Record of shunt revision complications and outcome was maintained by the principal author. The data of all the cases were analyzed.

RESULTS

The age of children varied from 1 month to 12 yr (mean 2.2 yr). The most common etiology of hydrocephalus was aqueductal stenosis in 18 (36%) children. Post infective hydrocephalus, either of post-tubercular meningitis (TBM) or following bacterial meningitis, remained the cause in 15 children (30%). Congenital TORCH infection was responsible for 3 cases of hydrocephalus making infective etiology as the cause in 18 (36%) cases. Intra 4th ventricular neurocysticercus cyst caused blockade of CSF pathway in 2 children. 15 out of 50 children required shunt revision, either due to infection (8,16%) or shunt obstruction (7, 14%). Multiple shunt revisions were required in 2 children only. These revisions were required due to infection, obstruction or malfunction of the shunt.

CONCLUSIONS

Infective etiology is responsible for hydrocephalus in significant number of children (36%). The possibility of TORCH infection, as a cause of hydrocephalus should be considered even amongst the children of screened mothers during antenatal check-up. Pure intra 4th ventricular neurocysticercus cysts (without intraparenchymal cyst), though rare, can manifest with outlet obstruction. Incidence of shunt revision using Chhabra's medium pressure shunt is very high in children at an average follow up of 1.6 yr. Post infective hydrocephalus is a major cause of delayed milestones, contributing to mental retardation.

Giardia intestinalis and other zoonotic parasites: Prevalence in adult dogs from the southern part of Mexico City

The protozoan Giardia intestinalis is a mammalian-infecting parasite. It produces diarrhoea and malabsorption in its hosts. There is growing evidence that dogs could be reservoirs and play an important role in transmission. In Mexico, there are few data on the frequency of G. intestinalis. Therefore, we studied the small intestine of stray dogs, euthanazed at the "Culhuacan" Control Canine Centre, towards the end of 1997 and during the summer of 1998. We microscopically analysed intestinal contents and mucus samples taken every 3cm. During the cold season (winter), parasites were not found in 38/100 dogs, in contrast to 8/100 through the warm season. We found that 42/100 in winter and 51/100 in summer harboured G. intestinalis. To our knowledge, these G. intestinalis frequencies are the highest found in adult dogs worldwide. The results showed a rise in Ancylostoma spp. from 23/100 to 67/100 during the cold and warm seasons. Toxocara canis frequencies varied between 12/100 and 18/100, respectively. The data suggest that the probability of infection is higher during the hottest months compared to the coldest months of the year. Both puppies and adult dogs are highly infected. Dogs are reservoirs for zoonotic parasites; for this reason, it is imperative for humans to avoid fecal contamination in streets, public gardens and parks.

Toxocariasis of the central nervous system: with report of two cases

Clinical involvement of the nervous system in visceral larva migrans due to Toxocara is rare, although in experimental animals the larvae frequently migrate to the brain. A review of the literature from the early 50's to date found 29 cases of brain involvement in toxocariasis. In 20 cases, various clinical and laboratory manifestations of eosinophilic meningitis, encephalitis, myelitis or radiculopathy were reported. We report two children with neurological manifestations, in which there was cerebrospinal fluid pleocytosis with marked eosinophilia and a positive serology for Toxocara both in serum and CSF. Serology for Schistosoma mansoni, Cysticercus cellulosae, Toxoplasma and cytomegalovirus were negative in CSF, that was sterile in both cases. Improvement of signs and symptoms after specific treatment (albendazole or thiabendazole) was observed in the two cases. A summary of data described in the 25 cases previously reported is presented and we conclude that in cases of encephalitis and myelitis with cerebrospinal fluid pleocytosis and eosinophilia, parasitic infection of the central nervous system should be suspected and serology should be performed to establish the correct diagnosis and treatment.

Neurocysticercosis and acquired cerebral toxoplasmosis in children

Neurocysticercosis, prevalent wherever pigs are raised in the presence of poor sanitation, is the most common identifiable cause of new-onset epilepsy throughout the developing world. As immigration patterns have changed, children with neurocysticercosis are seen throughout the United States. Acute cysticercosis, the most common manifestation in children, reflects the host response to the dying parasite. Children typically present with seizures and have an excellent prognosis. Neuroimaging demonstrates a single ring or nodular enhancing lesion surrounded by edema. Short-term anticonvulsant therapy is indicated, but treatment with antiparasitic agents is not required. Other forms, such as active cysts (intact organism), intraventricular or subarachnoid racemous cysticercosis, and cysticercal meningoencephalitis, are less common manifestations of parasitic infection. Toxoplasmosis, caused by the parasite Toxoplasma gondii, can be acquired by ingestion of infected undercooked meat or from oocytes shed in cat feces. Acquired cerebral toxoplasmosis, due to primary or reactivated infections, rarely occurs in immunocompetent children. In children who are immunodeficient as the result of AIDS, chemotherapy, tissue transplantation, or congenital immunodeficiency, toxoplasmosis may be difficult to distinguish from cerebral lymphoma. A variety of techniques, including neuroimaging, Thallium-201 SPECT, polymerase chain reaction analysis of CSF, and special histological methods, may be used to diagnose acquired toxoplasmosis. Antiparasitic therapy, using pyrimethamine and sulfadiazine, and serial neuroimaging often enable clinicians to differentiate toxoplasmosis from other central nervous system lesions. Toxoplasmosis may respond to other antimicrobials, including macrolide antibiotics, dapsone, clinidamycin, and atovaquone. Suppressive treatment is generally required for life in immunodeficient patients. Immunodeficient children with acquired toxoplasmosis have high rates of mortality and neurological sequelae.

The compromised traveler

Compromised travelers represent a diverse and challenging group of individuals. They include HIV-infected patients who are at risk for potentially adverse reactions to immunizations, and new exposures to enteric water-borne opportunistic pathogens associated with chronic infections. Such travelers may encounter unfamiliar opportunistic fungi and classical tropical infections, such as leishmaniasis, whose pathogenesis can be enhanced by the presence of prior HIV infection. Other immunocompromised groups include those who are functionally or anatomically asplenic, and patients who are iatrogenically immunosuppressed from medications utilized for solid organ transplantation, chemotherapy, or treatment of malignancies. This population of travelers also includes those with diabetes mellitus who may require adjustments in their dosing, administration, and possibly even the types of insulin used on their trips. These patients are also at greater risk for acquisition of tuberculosis, severe community-acquired pneumonia, urinary tract infections, and pyomyositis. Older travelers present both the infectious disease and travel medicine specialist with issues such events, malignancy-related infections, myocardial infarction, and other forms of cardiopulmonary compromise, which the authors address in this article.