Meningomielitis asociadas a infección por herpes virus humano 7: Comunicación de dos casos / Meningomyelitis associated with infection by human herpes virus 7: Report of two cases

Human herpesvirus 7 (HHV-7) may cause encephalomyelitis in immune competent adults. We report two patients infected by the virus. A 34-year-old male presenting with paraparesis and a sensitive deficiency located in D6 dermatome. Cerebrospinal fluid had 35 white blood cells per mm³ and 75 mg protein per dl. A PCR-microarray examination was positive for HHV-7. The patient was treated with prednisolone and ganciclovir with full recovery. A 27-year-old male presenting with headache, fever and diarrhea. Cerebrospinal fluid analysis showed 160 cells per mm³ and 75 mg protein per dl. Viral RNA detection was positive for HHV-7. The patient was managed with analgesia and rest and was discharged with the diagnosis of viral meningitis. Our communication supports the notion that HHV-7 may be considered as pathogen factor in humans, even in immune competent ones.

Diagnosis and quantitative detection of HSV DNA in samples from patients with suspected herpes simplex encephalitis

Diagnosis of herpes simplex encephalitis (HSE) is based on the detection of herpes simplex virus (HSV) DNA in patients' CSF samples. HSV DNA quantitation has the potential for estimating the effects of antiviral therapy. The aim of this study was to diagnose HSV DNA in HSE suspected patients and the quantitative analysis of its genome using real-time PCR to assess the value of the viral load in the course of antiviral treatment. The CSF samples were collected from 236 consecutive HSE suspected patients from November 2004 to May 2008. Upon DNA extraction, the samples were analyzed by Real-Time PCR assay. A set of primers amplified a common sequence of HSV glycoprotein B gene. The copy numbers of unknown samples were expressed via a standard curve drawn with a known amount of amplified cloned plasmid. Of the 236 samples, 137 (58 percent) came from males and 99 (42 percent) from females. The HSV genome was detected in 22 (9.3 percent) patients by PCR, 13 males/ 9 females. Serial CSF samples were available from 10 of the 22 patients. The range of the HSV DNA copy numbers in the clinical samples ranged from 2.5 × 10² to 1.7 × 10(6) copies/mL of CSF. Quantitative PCR results can be helpful in evaluating the efficacy of antiviral therapy in the above-mentioned patients. There is an association between the initial viral load and the duration of treatment course.

review article on herpes simplex encephalitis

Herpes Simplex encephalitis [HSE] is a life threatening outcome of Herpes simplex virus [HSV] infection of the central nervous system [CNS]. HSV accounts for 2-5 percent of all cases of encephalitis. One third of cases occur in those younger than 20 years old and one half in those older than 50 years old. Clinical diagnosis is recommended in the encephalopathic, febrile patients with focal neurological signs. However, the clinical findings are not pathogonomic because numerous other diseases of CNS can mimic HSE. Diagnosis should be confirmed based on medical history, analysis of cerebrospinal fluid [CSF] for protein and glucose contents, the cellular analysis and identifying the pathogens by serology and Polymerase Chain Reaction [PCR] amplification .The diagnostic gold standard is the detection of HSV DNA in the cerebrospinal fluid by PCR. But negative results need to be interpreted regarding the patients clinical signs and symptoms and the time of CSF sampling. Spike and slow wave patterns is observed in Electroencephalogram [EEG]. Neuroimaging, especially Magnetic Resonance Imaging [MRI] is essential for evaluating the patients, which shows temporal lobe edema or hemorrhage. All patients with HSE should be treated by intravenous Acyclovir [10mg/kg q8hr for 14-21 days]. After completing therapy, PCR of the CSF can confirm the elimination of replicating virus, assisting further management of the patient

Encefalitis: ¿cuáles y cómo tratar? / Encephalitis: which are and how to treat?

La causa más frecuente de encefalitis es la infección viral que invade el SNC por vía sanguínea (p ej.: enterovirus) , nervios periféricos (p ej.: rabia) y menos frecuentemente, vía nervio olfatorio (p ej.: amebas de vida libre). El compromiso focal de las células nerviosas explica las variaciones sintomáticas. En nuestro medio ningún virus predomina ostensiblemente y las características epidemiológicas y clínicas pueden crear confusión inicial. La encefalitis herpética es una emergencia neurológica por la necesidad de un diagnóstico precoz, para instalar el tratamiento específico. El VHS-1 es importante en niños y los adultos; VHS-2 en el neonato. El rendimiento del aislamiento viral en el LCR es bajo, la RPC tiene una sensibilidad aproximada de 91 por ciento y alta especificidad permaneciendo positiva hasta cinco a siete días después de iniciada la sintomatología y/o el tratamiento. El EEG es sensible pero poco especifico. La RM es el examen imagenológico indicado en etapa aguda; la TAC permite controlar la evolución. La biopsia cerebral se reserva para casos con falta de respuesta objetiva al tratamiento. El aciclovir reduce la letalidad y las secuelas de la encefalitis herpética, dosis de 60 mg/kg/d en recién nacidos han elevado su sobrevida. Valaciclovir y famciclovir, con similar actividad antiviral, podrían emplearse para prolongar el efecto antiviral más allá de 21 días. En la encefalitis por enterovirus las manifestaciones cutáneas o la miocarditis pueden orientar el diagnóstico etiológico inicialmente. Se debate la capacidad de Mycoplasma pneumoniae para producir trastornos del SNC, si bien invade el LCR, no se ha logrado definir su rol patógeno. Menos importantes son VHH-6, virus de Epstein-Barr, adenovirus, Bartonella henselae, Cryptococcus neoformans, Leptospira sp. y otros. Es posible que nuevos tratamientos específicos estimulen el desarrollo de tecnologías que nos permitan conocer mejor los reales agentes de encefalitis aguda en nuestro país.