Prevalence of human cryptosporidiosis in the Americas: systematic review and meta-analysis

ABSTRACT Cryptosporidiosis is a disease caused by the Cryptosporidium spp parasite. As some species of Cryptosporidium have a wide host spectrum, the characterization of the pathogen at the species or genotype level is of great importance to define the sources of infection for humans and the potential for public health. This study investigated the diversity of the genus Cryptosporidium spp. in humans from all over the American continent and observed whether the method used to search for the parasite influenced the prevalence found in the Americas. This systematic review was carried out using the Pubmed, Science direct, Lilacs, Scielo, and Scopus databases with publications from January 1, 2010, to December 31, 2020. For data synthesis, the PRISMA flowchart was used and for the meta-analysis we used the MetaXL program. Of the selected publications, 57, 9 and 16 belonged to the region of South, Central and North America, respectively. The prevalence found for South, Central, and North America was 7%, 7%, and 8%, respectively, when analyzing publications that used only the microscopy method. When we analyzed the publications that used immunological and molecular methods, we found prevalences of 10%, 9%, and 21% for South, Central, and North America, respectively. The C. hominis subtype IbA10G2 was the most reported in the American continent, followed by subtype IeA11G3T3 and, for C. parvum, subtype IIaA15G2RI was the most reported. In conclusion, Cryptosporidium spp. is present throughout the American continent and its prevalence is higher when immunological and/or molecular methods are used, in addition to direct microscopic examination.

Use of Cerebrospinal Fluid for the Diagnosis of Neuroinvasive Dengue, Zika, and Chikungunya: A 19-year systematic review

Abstract INTRODUCTION: Cerebrospinal fluid analysis contributes to the diagnosis and neuropathogenesis of neuroinvasive arboviruses. Neurological complications caused by dengue, Zika, and chikungunya infections have high clinical relevance because of their high potential to cause death or neurological deficits. We aimed to evaluate the use of cerebrospinal fluid assays for diagnostic support in neurological disorders associated with dengue, chikungunya, and Zika infections. METHODS: A systematic review was carried out by searching the electronic databases LILACS, PubMed, Scopus, and Embase for articles written in English, Portuguese, or Spanish in the last 19 years. Published studies were reviewed using the terms "dengue," "Zika", "chikungunya", alone or in combination with "cerebrospinal fluid" in the period from 2000 to 2019. RESULTS: A total of 98,060 studies were identified; of these, 1.1% (1,041 studies, 58,478 cases) used cerebrospinal fluid assays for neurological investigations. The most frequent neurological disorders included encephalitis (41.4%), congenital syndromes (17%), and microcephaly associated with Zika virus infections (8.9%). Neuroinvasive disorders were confirmed in 8.03% of 58,478 cases by specific cerebrospinal fluid analyses. The main methods used were IgM-specific antibodies (66%) and reverse transcription-polymerase chain reaction (10%). The largest number of scientific papers (29%) originated from Brazil, followed by India (18.4%) and the United States (14.4%). CONCLUSIONS: Although cerebrospinal fluid analysis is of great importance for increasing neurological diagnostic accuracy and contributes to the early diagnosis of neuroinvasive dengue, chikungunya, and Zika infections, it is underused in routine laboratory investigations worldwide.

Cerebrospinal fluid challenges for the diagnosis of herpes simplex infection in the central nervous system / Desafios do exame do líquido cefalorraquidiano para o diagnóstico de infecção por herpes simplex no sistema nervoso central

Abstract Herpes simplex virus (HSV) is a cause of a severe disease of the central nervous system (CNS) in humans. The demonstration of specific antibodies in the cerebrospinal fluid (CSF) may contribute to the retrospective neurological diagnosis. However, the commercial immunological tests for HSV infection are for use in serum samples. Objective: The aim of the present study was to adapt a commercial kit anti-HSV IgG used for serum samples to be performed with a CSF sample. Methods: Forty CSF specimens from 38 patients with suspected CNS HSV infection were serially diluted for detecting anti-HSV IgG by enzyme immunoassay (EIA). The same samples were also analyzed with the polymerase chain reaction (PCR). Results: The sensitivity of EIA test for HSV was 5% (dilution 1:40) and 65% (dilution 1:2) in CSF, and HSV DNA PCR was 15%. The combined analysis of EIA (dilution 1:2) and PCR increased the sensitivity up to 72.5%. The inflammatory CSF was associated with positive HSV PCR. Conclusions: We demonstrated the importance to adapt serological anti-HSV IgG EIA test for CSF assays to increase the accuracy of the analysis, considering the low concentration of specific antibodies in CSF.

Resumo O vírus herpes simples (HSV) é um dos agentes causadores de uma doença grave no sistema nervoso central (SNC) em humanos. A detecção de anticorpos específicos no líquido cefalorraquidiano (LCR) pode contribuir para o diagnóstico neurológico retrospectivo. Entretanto, os testes imunológicos comerciais são para uso em amostras de soro. Objetivo: Adaptar um kit comercial sorológico anti-HSV IgG para ser utilizado no de LCR. Metodos: Quarenta amostras de LCR de 38 pacientes com suspeita de infecção por HSV no SNC foram diluídas pesquisa de anticorpos anti-HSV IgG pelo método imunoenzimático (EIA). Além disso, as mesmas amostras também foram analisadas por reação em cadeia da polimerase (PCR). Resultados: A sensibilidade do teste EIA para o HSV consistiu em 5% (diluição 1:40) e 65% (diluição 1:2) no LCR, e o PCR do DNA do HSV, 15%. A análise combinada de EIA (diluição 1:2) e PCR aumentou a sensibilidade para 72,5%. Houve associação entre presença do LCR inflamatório e PCR positiva para HSV. Conclusões: Demonstramos a importância na adaptação previa do teste sorológico anti-HSV IgG EIA para ensaios do no LCR, a fim de aumentar a acuracia da análise, considerando a baixa concentração de anticorpos específicos no LCR.

A comparison of nontreponemal tests in cerebrospinal fluid for neurosyphilis diagnosis: equivalent detection of specific antibodies / Uma comparação de testes não treponêmicos no líquido cefalorraquidiano para diagnóstico de neurossífilis: detecção equivalente de anticorpos específicos

ABSTRACT Syphilis is a re-emerging sexually-transmitted infection, caused by the spirochete Treponema pallidum, that may penetrate early into the central nervous system. The venereal disease research laboratory test (VDRL) on the cerebrospinal fluid (CSF) is the most widely used for neurosyphilis diagnosis. We evaluated the performance of two other nontreponemal tests (rapid plasma reagin [RPR] and unheated serum reagin [USR] tests) in comparison with the VDRL in CSF. Methods: We analyzed CSF samples from 120 individuals based on VDRL reactivity in the CSF and the clinical picture of neurosyphilis. Results: High inter-rater reliability was found among all three tests, with equivalent sensitivity and specificity. Intraclass correlation coefficient for absolute agreement was 1 for VDRL versus USR, 0.99 for VDRL versus RPR, and 0.99 for RPR versus USR. Conclusions: Rapid plasma reagin and unheated serum reagin tests were identified as excellent alternatives for neurosyphilis diagnosis.

RESUMO A sífilis é uma infecção reemergente sexualmente transmissível pelo espiroqueta Treponema pallidum, que pode penetrar precocemente no sistema nervoso central. O teste venereal disease research laboratory test (VDRL) no líquido cefalorraquidiano (LCR) é o mais amplamente utilizado para diagnóstico de neurossífilis. Avalia-se o desempenho de dois outros testes não treponêmicos (rapid plasma reagin - RPR and unheated serum reagin - USR tests) em comparação ao VDRL no LCR. Métodos: Foram analisadas amostras de LCR de 120 indivíduos com base no quadro clínico compatível com neurossifilis e reatividade no VDRL no LCR. Resultados: Os testes apresentaram elevada concordância. O coeficiente de correlação intraclasse para concordância absoluta foi de 1 para VDRL versus USR, 0,99 para VDRL versus RPR e 0,99 para RPR versus USR. Conclusões: Os testes rapid plasma reagin e unheated serum reagin foram identificados como excelentes alternativas para o diagnóstico de neurossífilis.

Neurological complications in dengue infection: a review for clinical practice / Complicacoes neurologicas na dengue: uma revisao para a pratica clinica

Dengue is an important global public health problem. The World Health Organization estimates that 2/5 of entire world population are in risk of dengue infection. Almost 50 millions cases occur annually, with at least 20 thousand deaths. The etiological agent of this acute febrile disease is a single-strand positive-sense RNA virus of Flavivirus genus. It is an arboviral disease transmitted by Aedes sp. mosquitoes (Aedes aegypti and A. albopictus). Most infected individuals present asymptomatic infection, but some may develop clinical signs. Therefore, a wide spectrum of illness can be observed, ranging from unapparent, mild disease, called dengue fever, to a severe and occasionally fatal dengue hemorrhagic fever/dengue shock syndrome. Currently, neurological manifestations related to dengue infections are increasingly been observed and appears as a challenge for medical practice. In this study the neurological complications of dengue infection will be reviewed, focusing a better understanding of the disease for the clinical practice.

A dengue é um importante problema de saúde pública. A Organização Mundial de Saúde estima que 2/5 da população mundial encontra-se em risco de desenvolver a infecção. Cerca de 50 milhões de casos ocorrem anualmente, com ao menos 20 mil mortes. O agente etiológico desta doença febril aguda é um vírus RNA, do gênero Flavivirus. Este arbovírus é transmitido pelo mosquito Aedes sp. A maioria dos indivíduos infectados apresenta infecção assintomática, porém alguns desenvolvem sintomas clínicos. Estes manifestações podem variar desde uma doença inaparente, branda, conhecida como febre da dengue, até uma forma severa, sendo fatal em alguns casos como na febre hemorrágica da dengue/síndrome de choque da dengue. Atualmente, manifestações neurológicas associadas à dengue são cada vez mais frequentes, tornando-se um desafio na rotina médica. Neste estudo, as complicações neurológicas da dengue serão revisadas, com ênfase na melhor compreensão acerca da doença para a prática clínica.

HAM/TSP: association between white matter lesions on magnetic resonance imaging, clinical and cerebrospinal fluid findings / HAM/TSP: associação entre lesões de substância branca à ressonância magnética, achados clínicos e do líquido cefalorraquidiano

OBJECTIVE: To investigate the association between clinical data, white matter lesions and inflammatory cerebrospinal fluid (CSF) findings in HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP). METHOD: We studied brain and cervical spinal cord on magnetic resonance imaging (MRI) and CSF examinations of 28 Brazilian HAM/TSP patients. RESULTS: The majority of patients had severe neurological incapacity with EDSS median of 6.5 (3-8). The brain MRI showed white matter lesions (75%) and atrophy (14%). The preferential brain location was periventricular. Cervical demyelination lesions occurred in 11% of the cases, and cervical atrophy in 3.5%. One patient had enhancement lesions on T1 cervical spinal cord MRI. Cases with spinal cord lesions had signs of acute CSF inflammation. The brain white matter lesions predominated in the patients with higher age. CONCLUSION: Our data suggest that an active inflammatory process is associated with the cervical spinal cord lesions in HAM/TSP. The brain abnormalities are not related to the clinical picture of HAM/TSP.

OBJETIVO: Analisar a associação entre aspectos clínicos, lesões de substância branca e reação inflamatória aguda no líquido cefalorraquidiano (LCR) na mielopatia associa ao HTLV-1 (HAM/TSP). MÉTODO: Foram estudadas ressonâncias magnéticas (RM) do encéfalo/medula espinhal cervical e exame do LCR de 28 pacientes com HAM/TSP. RESULTADOS: A maioria dos pacientes apresentava grave incapacidade neurológica, com EDSS 6,5 (3-8). A RM revelou lesões da substância branca (75%) com predominância periventricular e atrofia cortical (14%). Lesões desmielinizantes cervicais ocorreram em 11% dos casos e atrofia em 3,5%. Um paciente apresentou lesão cervical na T1 com captação de contraste. Sinais de inflamação aguda no LCR ocorreram em situações de lesão da medula espinhal cervical. As alterações de substância branca do encéfalo predominaram nos indivíduos com maior faixa etária. CONCLUSÃO: Nossos achados sugerem que processo inflamatório com atividade clínica na HAM/TSP está associado a lesões da medula espinhal cervical. As anormalidades da substância branca encefálicas não são relacionadas ao quadro clínico de HAM/TSP.