Care of a child with human herpesvirus-6B encephalitis after chimeric antigen receptor T-cell therapy / 中国实用护理杂志

Summarizing the nursing experience of a child with HHV-6B encephalitis after umbilical cord blood transplantation and CAR-T therapy. The child was 4 years old and was diagnosed with acute T lymphocytic leukemia on May 28, 2021. Nursing points: meticulously observe symptoms for early diagnosis and treatment; develop a specialized management plan, implement individualized care; enhance medication management to improve the quality of care; establish a shared decision-making communication model to prevent hospital-acquired infections; provide patient-centered care for lumbar puncture; assess the needs of the child and family, alleviate negative emotions; improve pre-discharge preparation, emphasize continuity of care. With proactive treatment and careful nursing, the child′s condition improved, and they were discharged. Follow-up for six months showed the child in a sustained remission state with no adverse sequelae, and normal life resumed.

A case of human herpesvirus 6B encephalitis after liver transplantation and literature review / 国际生物医学工程杂志

Human herpesvirus-6 (HHV-6) is a ubiquitous virus. The incidence of HHV-6 after liver transplantation is estimated to be 22% ? 54%; it may present with fever, hepatitis, pneumonia, encephalitis, and myelosuppression and has a poor prognosis. HHV-6(+) recipients had a mortality rate of 29%, significantly higher than that of HHV-6(?) recipients (6%). Since most infections are asymptomatic, HHV-6 monitoring is not routinely performed in clinical practice, which means clinicians often ignore the diagnosis of HHV-6 and eventually delay diagnosis and treatment. In this paper, a case of human herpesvirus 6B encephalitis after liver transplantation was retrospectively analyzed, and the literature related to this disease was reviewed to improve the understanding of this disease.

A case of human herpesvirus 6 severe encephalitis followed by secondary anti-N-methyl-D- aspartate receptor encephalitis in an infant / 中华神经科杂志

Human herpesvirus 6 encephalitis (HHV-6) is relatively rare in children with normal immune function, and its secondary autoimmune encephalitis is even more rarely reported. A previously healthy 1-year-old boy who presented with fever, convulsions and partial status epilepticus was reported. He was diagnosed with severe HHV-6 encephalitis by next generation sequencing of cerebrospinal fluid pathogens. After aggressive antiviral treatment, the symptoms improved, but his condition recurred again with frequent involuntary movements and was finally diagnosed with secondary anti-N-methyl-D-aspartate receptor encephalitis. After treatment with gamma globulin, high-dose cortico-steroids and rituximab, his condition got stable but was left with encephalomalacia, developmental delay and intractable epilepsy in the long term.

Síndrome de reacción a drogas con eosinofilia y síntomas sistémicos asociado a herpesvirus humano 6. Caso pediátrico tratado con ciclosporina y corticoides / Drug reaction with eosinophilia and systemic symptoms syndrome associated with human herpesvirus 6. A pediatric case treated with cyclosporine and corticosteroids

La reacción a drogas con eosinofilia y síntomas sistémicos es una reacción adversa cutánea rara, potencialmente grave. Puede presentar fiebre, erupción cutánea polimorfa, edema facial y/o linfoadenopatías. La reactivación del virus herpes humano tipo 6 se asocia a un curso más grave y/o prolongado.Un lactante de 22 meses en tratamiento con fenobarbital presentó lesiones eritematopapulares, fiebre, leucocitosis, proteína C reactiva elevada y alteración de pruebas hepáticas. Se realizó biopsia de piel compatible con reacción adversa a drogas. Se trató con corticoides sistémicos e inmunoglobulina intravenosa sin respuesta. La reacción en cadena de la polimerasa para virus herpes humano tipo 6 resultó positiva. Se inició ciclosporina más prednisona, con buena respuesta. Existe poca evidencia del uso de ciclosporina en adultos, cuando los corticoides sistémicos son inefectivos. Este es el primer reporte pediátrico Podría ser una alternativa efectiva o un complemento de los corticosteroides sistémicos cuando no responde a tratamientos convencionales.

Drug reaction with eosinophilia and systemic symptoms is a rare and potentially serious skin adverse reaction, with fever, polymorphous skin rash, facial edema, and/or lymphadenopathy. Reactivation of human herpes virus type 6 has been associated with a more severe and/or prolonged course. A 22-month-old infant under phenobarbital treatment developed erythematous-papular lesions, fever, leukocytosis, elevated C-reactive protein, and abnormal liver tests. The skin biopsy was compatible with an adverse drug reaction. Treatment with systemic corticosteroids and intravenous immunoglobulin had no response. Polymerase chain reaction for human herpesvirus type 6 was positive, and cyclosporine plus prednisone was started with a good response. There is little evidence for the use of cyclosporine in adults when systemic corticosteroids are ineffective. This is the first report of pediatric drug reaction with eosinophilia and systemic symptoms treated with cyclosporine, which could be an effective alternative or an adjunct to systemic corticosteroid therapy unresponsive to conventional treatments.

Infección por Herpes virus Humano tipo 6 relacionado con manifestaciones dermatológicas y fatiga crónica: serie de casos / Human Herpesvirus type 6 infection related to dermatological manifestations and chronic fatigue: case series

Resumen Introducción: Las manifestaciones clínicas más frecuentes causadas por el Herpes Virus Humano Tipo 6 (HHV-6) ocurren en niños menores de 2 años, presentan lesiones en piel tipo roséola o exantema súbito. En adultos, las manifestaciones clínicas relacionadas a HHV-6 son muy variables, y pueden sobreponerse con otras afecciones. Objetivo: Presentar una serie de casos de pacientes diagnosticados con infección activa por HHV-6, quienes mostraban manifestaciones neurológicas, dermatológicas y de fatiga crónica. Materiales y métodos: Se realizó análisis de historias clínicas de 6 pacientes que fueron diagnosticados con infección activa por HHV-6, a través de métodos moleculares. Resultados: Se reportan 6 pacientes que fueron diagnosticados con infección activa por HHV-6 mediante métodos moleculares, quienes presentaron manifestaciones clínicas comunes tales como: fiebre, cefalea, depresión, decaimiento, pérdida de memoria y concentración, dolor fibromuscular, dolor poliarticular, sueño no reparador, exantema, nevus rubí, liquen plano y parestesias. Conclusiones: A través de esta serie de casos se espera resaltar la importancia de identificar la infección activa por HHV-6 a través de métodos moleculares, y sensibilizar a la comunidad médica sobre el papel que juega el virus en la evolución de diversas patologías.

Abstract Introduction: The most frequent clinical manifestations of Human Herpesvirus 6 (HHV-6) in children under 2 years of age are roseola-like skin lesions and sudden rash. In adults, the clinical manifestations associated with HHV-6 are highly variable and can overlap with other conditions. Objective: To present a case series of patients diagnosed with active HHV-6 infection, who showed neurological, dermatological and chronic fatigue manifestations. Materials and methods: An analysis of medical records of 6 patients who were diagnosed with active HHV-6 infection through molecular methods was performed. Results: 6 patients were diagnosed with active HHV-6 infection using molecular methods, who had common clinical manifestations such as fever, headache, depression, tiredness, loss of memory and concentration, fibromuscular pain, polyarticular pain, nonrestorative sleep, rash, ruby nevus, lichen planus and paresthesia. Conclusions: This case series highlights the importance of identifying active HHV-6 infection through molecular methods and creating awareness in the medical community of the role that the virus plays on the development of diverse pathologies.

Serum levels of matrix metalloproteinase-2, -9, and vitamin D in patients with multiple sclerosis with or without herpesvirus-6 seropositivity

ABSTRACT In recent years, extreme attention has been focused on the role of human herpesvirus-6 (HHV-6) in multiple sclerosis (MS) pathogenesis. However, the pathogenesis of MS associated with HHV-6 infection remains unknown. In this study, we measured the serum levels of matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9), and vitamin D levels in MS patients with HHV-6 infection and MS patients without HHV-6 infection. Five hundred sixty (including 300 females and 260 males) MS patients along with 560 healthy subjects were analyzed for HHV-6 seropositivity using enzyme-linked immunosorbent assay (ELISA). Subsequently, we measured the serum levels of MMP-2, MMP-9, and vitamin D levels in MS patients with HHV-6 infection and MS patients without HHV-6 infection by ELISA. About 90.7% of MS patients (508/560) were seropositive for HHV-6, while 82.3% (461/560) of healthy subjects were seropositive for this virus (p = 0.001). Moreover, there was a significant increase in the levels of MMP-2, MMP-9, and lower vitamin D in the serum samples of MS patients when compared with healthy subjects. Additionally, we demonstrated that the MMP-9 levels in seropositive MS patients were significantly higher than seronegative MS patients (p = 0.001). Finally, our results demonstrated that the mean of expanded disability status scale (EDSS) in seropositive MS patients was significantly higher in comparison to seronegative MS patients (p < 0.05). In conclusion, we suggest that the HHV-6 infection may play a role in MS pathogenesis.

Research progress on human herpesvirus 6 infection after liver transplantation / 器官移植

Human herpesvirus 6 (HHV-6) may establish lifetime latency after initial invasion of the host, and liver transplant recipients may experience reactivation of latent infection during immunosuppression. HHV-6 infection in liver transplant recipients could lead to fever, hepatitis, encephalitis and graft dysfunction, and indirectly increases the risk of progression of liver fibrosis due to cytomegalovirus (CMV), hepatitis C virus (HCV) infection. At present, the pathogenesis of HHV-6 infection after liver transplantation has not been systematically elucidated, and effective prevention and treatment strategies are still lacking. This article provided a review for the research progress on the pathogenesis, risk factors, diagnosis and treatment of HHV-6 infection after liver transplantation.

Human herpesvirus 6A active infection in patients with autoimmune Hashimoto's thyroiditis

ABSTRACT Background: Hypothyroidism due to Hashimoto's thyroiditis (HT) is the commonest autoimmune endocrine illness in which antibodies against thyroid organ result in inflammation. The disease has a complex etiology that involves genetic and environmental influences. Viral infections may be involved in triggering of the disease as their molecular mimicry enhance autoimmune responses. Human herpesvirus-6 (HHV-6) is recognized for its contribution to some autoimmune diseases. Objective: In the current study, the prevalence of HHV-6 active infection in patients with HT and with non-autoimmune thyroid disorders were compared with patients with euthyroidism. In addition, a correlation between presence of HHV-6 infections and HT was investigated. Methods: A total of 151 patients with clinically and laboratory confirmed HT, 59 patients with non-autoimmune thyroid disorders, and 32 patients with normal thyroid function were included in the study. For further confirmation of HT disease, all the precipitants were tested for anti-thyroid peroxidase (TPO), and anti-thyroglobulin (TG) antibodies. For detection of both HHV-6 types A and B, nested PCR and restriction enzyme digestion were used. HHV-6 DNA positive samples were further investigated by DNA sequencing analysis. Results: HHV-6A DNA was found in serum sample of 57 out of 151 patients (38%) with HT, which was significantly more often than in patients with non-autoimmune thyroid disorders (p = 0.001). However, HHV-6 DNA was not detected in serum samples of euthyroid subjects. Conclusions: The results support a possible role for active HHV-6A infection, demonstrated by the presence of HHV-6 DNA in sera, in the development of HT.

Encefalopatía por virus herpes 6 como complicación de exantema súbito / Encephalopathy due to human herpesvirus 6 infection as exanthema subitum complication

La principal manifestación clínica del herpesvirus 6 es el exantema súbito (también conocido como roséola o sexta enfermedad) y el síndrome febril. Las manifestaciones en el sistema nervioso central no son infrecuentes en la infección por herpesvirus 6, y su fisiopatología no está esclarecida, pero precisan diagnóstico y tratamiento temprano para evitar secuelas potencialmente graves. Se presenta el caso de una niña inmunocompetente de 2 años con cuadro de encefalitis como complicación de infección por herpesvirus 6. Se destaca la importancia del diagnóstico oportuno a fin de instaurar un adecuado tratamiento y seguimiento para evitar complicaciones secundarias a la afectación del sistema nervioso central.

The main clinical manifestation of human herpesvirus 6 is exanthema subitum (also known as roseola infantum) and febrile syndrome. Central nervous system manifestations are not unusual in herpesvirus 6 infection, and even though the pathophysiology is not clear, they need to be early diagnosed and treated in order to avoid potentially serious damage. We present the case of an immunocompetent 2-year-old girl with encephalitis as a complication of herpesvirus 6 infection. We want to emphasize the significance of an early diagnosis and treatment in order to prevent further complications due to the central nervous system extension.

Recovery without Neurological Sequelae in Fulminant Cerebral Edema in Pediatric Encephalitis with Human Herpesvirus Type 6 / 대한소아신경학회지

Viral encephalitis can lead to serious neurological sequelae and death among younger children. It is also known that the mortality rate in encephalitis with cerebral edema or transtentorial brain herniation is higher. A 4-year-old boy visited our emergency department exhibiting mental change. The patient had a high fever for four and a whole-body rash for three days prior to his visit. He had displayed irritable symptoms and been vomiting for six hours before his visit, accompanied by seizure. After 13 hours of admission, the patient's right pupil became fixed and fully dilated, and the left pupil also became fixed and fully dilated within 30 minutes. Brain computed tomography (CT) was performed immediately, and severe brain swelling with transtentorial brain herniation was found. The mannitol dose was increased and dexamethasone was also added. Hyperventilation was performed through intubation to reach PaCO₂ levels of 25 to 30mmHg. Fifteen hours later, pupillary reflex was observed and the cerebral edema and transtentorial brain herniation was found to be improving in follow-up brain CT. He was transferred to a general ward after 11 days and discharged on the thirteenth hospital day without any neurological sequelae. Human herpesvirus type 6 (HHV-6) was detected in the serological polymerase chain reaction (PCR) examination.

Association of occupational medicamentosa-like dermatitis induced by trichloroethylene and infection with human herpesvirus 6 and cytomegalovirus / 中国职业医学

OBJECTIVE: To explore the potential association between occupational medicamentosa-like dermatitis induced by trichloroethylene( OMDT) and past infection,reactivation and recent infection of human herpesvirus 6( HHV6) and human cytomegalovirus( HCMV). METHODS: Twenty OMDT patients were recruited as case group by using judgment sampling method. Twenty healthy workers occupationally exposed to trichloroethylene for more than half a year were randomly selected as exposure group. Twenty healthy people with no exposure history to trichloroethylene were randomly selected as control group. The enzyme linked immunosorbent assay was used to qualitatively determine the titer of HHV6 and HCMV immunoglobulin( Ig) G,Ig M antibodies from serum samples of these subjects. The polymerase chain reaction was used to qualitatively detect HHV6 and HCMV DNA from whole blood DNA samples of these subjects. The differences of previous infection rate,reactivation rate and recent infection rate of HHV6 and HCMV among these three groups of patients with different clinical types of OMDT were analyzed. RESULTS: The prevalence of HHV6 and HCMV infection in the case group was higher than that in the control group,and the difference was statistically significant( 65. 5% vs 20. 0%,75. 0% vs15. 0%,P < 0. 017). The reactivation rate of HHV6 and HCMV in the case group was higher than that in the control group,but the difference was not statistically significant( P > 0. 017). The recent infection rate of HHV6 and HCMV in the case group was not significantly different from that in the control group( P > 0. 017). There was no significant difference in the past infection rate,reactivation rate and recent infection rate of HHV6 and HCMV between the exposure group and the control group( P > 0. 05),meanwhile in different clinical types of OMDT patients( P > 0. 05). CONCLUSION: OMDT may be associated with past infection of HHV6 and HCMV.

Reactivation of human herpesvirus 6 and its clinical significance / 白血病·淋巴瘤

Human herpesvirus 6 (HHV-6) is recognized as a ubiquitous dsDNA virus in human with widespread cell tropism in vivo, which could induce lifelong latent infection and be reactivated in some immunocompromised individuals leading to serious diseases. With the increasing application of hematopoietic stem cell transplantation (HSCT), it is obvious that HHV-6 reactivation has a close relationship with several complications including encephalitis after transplantation. On the other hand, among about 1 % infected people, HHV-6 and subtelomeric region of cell chromosomes in the state of endogenous persistent infection play a part in activated virus infection. As the detection methods make a great progress in HHV-6 detection, clinical data reveals the relationship between HHV-6 reactivation and lots of chronic diseases, especially lymphoma, leukemia as well as some chronic hematopoietic and immunological diseases.

Significance of PCR detection of HHV6 in gastro biopsy on the course of diarrhea in patients with severe diarrhea after allogeneic hematopoietic stem cell transplantation / 中华血液学杂志

Objective@#To investigate the clinical significance of PCR detection of human herpesvirus 6 (HHV6) in gastro biopsy on the course of diarrhea in patients with severe diarrhea after allogeneic hematopoietic stem cell transplantation (HSCT) .@*Methods@#Data from a cohort of 45 HSCT recipients (including age, sex, transplantation conditions, graft-versus-host disease, treatments, clinical signs, outcome, HHV6, and other infections) performed between 2015 and 2016 were collected. Univariate analysis was used to evaluate influences between the different parameters.@*Results@#Of the 45 enrolled recipients, 21 patients (46.7%) presented HHV6 positive in gastro-biopsy during the analyzed period. The incidence of CMV viremia in the positive HHV6 group was comparable with that in the negative HHV6 group. But the incidence of EBV viremia in the positive HHV6 group was significantly higher than in the negative HHV6 group (P=0.028) . 44 out of 45 patients with severe diarrhea were given antiviral treatment with foscarnet and/or ganciclovir, the latter didn’t influence the course of the diarrhea.@*Conclusions@#Positive PCR results in GI tract samples didn’t necessarily reflect reactivation of HHV6. Further studies are needed to define the significance of HHV6 for GI tract symptoms after allo-HSCT.

Predicting Factors of Roseola Infantum Infected with Human Herpesvirus 6 from Urinary Tract Infection

PURPOSE: The aim of this study was to compare the clinical and laboratory features of infants with roseola infantum due to human herpesvirus 6 (HHV6) infection and those with urinary tract infection (UTI). METHODS: We retrospectively reviewed the medical records of children who were hospitalized at Cheil General Hospital and Women's Health Care Center, College of Medicine, Dankook University, and diagnosed as having HHV6 infection or UTI. RESULTS: Among the infants admitted between September 2014 and May 2016, 92 (male, 45 and female, 47) were included in the study and divided into a HHV6 infection group (n=50) and a UTI group (n=42). The relative risk of UTI compared with that of HHV6 infection increased with pyuria (P<0.001), increased with leukocytosis (mean white blood cell [WBC] count, 15,048±5,756/mm³ vs 87,916±54,056/mm³; P<0.001), increased with C-reactive protein (CRP) level (4.89±4.85 mg/dL vs 1.04±1.76 mg/dL; P<0.001), and younger age (6.3±3.2 months vs 18.3±12.6 months; P<0.001). The relative risk of HHV6 infection compared with that of UTI increased with fever duration (4.3±1.7 days vs 2.8±1.7 days; P<0.001) and decreased with platelet (PLT) count (373±94×10³/mm³ vs 229±90×10³/mm³; P<0.001). No significant differences were found between the HHV6 groups according to the presence or absence of pyuria. CONCLUSION: Pyuria, age, fever duration, WBC count, CRP level, and PLT count were the differentiating factors of HHV6 infection from UTI. However, sterile pyuria can occur in children with HHV6 infection. In the presence of pyuria, CRP level and PLT count were the strong predictors of UTI compared with HHV6.

Optimisation of a quantitative polymerase chain reaction-based strategy for the detection and quantification of human herpesvirus 6 DNA in patients undergoing allogeneic haematopoietic stem cell transplantation

Human herpesvirus 6 (HHV-6) may cause severe complications after haematopoietic stem cell transplantation (HSCT). Monitoring this virus and providing precise, rapid and early diagnosis of related clinical diseases, constitute essential measures to improve outcomes. A prospective survey on the incidence and clinical features of HHV-6 infections after HSCT has not yet been conducted in Brazilian patients and the impact of this infection on HSCT outcome remains unclear. A rapid test based on real-time quantitative polymerase chain reaction (qPCR) has been optimised to screen and quantify clinical samples for HHV-6. The detection step was based on reaction with TaqMan® hydrolysis probes. A set of previously described primers and probes have been tested to evaluate efficiency, sensitivity and reproducibility. The target efficiency range was 91.4% with linearity ranging from 10-106 copies/reaction and a limit of detection of five copies/reaction or 250 copies/mL of plasma. The qPCR assay developed in the present study was simple, rapid and sensitive, allowing the detection of a wide range of HHV-6 loads. In conclusion, this test may be useful as a practical tool to help elucidate the clinical relevance of HHV-6 infection and reactivation in different scenarios and to determine the need for surveillance.

Profound CD4+ T lymphocytopenia in human immunodeficiency virus negative individuals, improved with anti-human herpes virus treatment / Linfocitopenia T CD4+ grave, en individuos negativos para virus de immunodeficiencia humana, mejoró con tratamiento antivirus herpes humanos

Lymphocytopenia and CD4+ T lymphocytopenia can be associated with many bacterial, fungal, parasite and viral infections. They can also be found in autoimmune and neoplastic diseases, common variable immunodeficiency syndrome, physical, psychological and traumatic stress, malnutrition and immunosuppressive therapy. Besides, they can also be brought into relation, without a known cause, with idiopathic CD4+ T lymphocytopenia. Among viral infections, the Retrovirus, specially the human immunodeficiency virus, is the most frequently cause. However, many acute viral infections, including cytomegalovirus and Epstein Barr virus can be associated with transient lymphocytopenia and CD4+ T lymphocytopenia. As is well known, transient lymphocytopenia and CD4+ T lymphocytopenia are temporary and overcome when the disease improves. Nonetheless, severe CD4+ T Lymphocytopenia associated with chronic infections by human herpes virus has not been reported. We describe 6 cases of human immunodeficiency virus negative patients, with chronic cytomegalovirus and Epstein Barr virus infections and profound lymphocytopenia with clinical symptoms of cellular immunodeficiency. These patients improved rapidly with ganciclovir or valganciclovir treatment. We claim here that it is important to consider the chronic human herpes virus infection in the differential diagnosis of profoundly CD4+ T lymphocytopenia etiology, when human immunodeficiency virus is absent, in order to start effective treatment and to determine, in future studies, the impact of chronic human herpes virus infection in human beings' health.

Múltiples enfermedades bacterianas, micóticas, parasitarias y virales pueden asociarse con linfocitopenia y linfocitopenia CD4+. También enfermedades autoinmunes, neoplásicas, inmunodeficiencia común variable, estrés físico, sicológico o traumático, la malnutrición y el tratamiento con inmunosupresores. Esta condición también se presenta sin causa aparente y es conocida como linfocitopenia T CD4+ idiopática. Entre las infecciones virales, los retrovirus, especialmente el virus de inmunodeficiencia humana, es la más frecuente causa, pero muchas otras infecciones virales agudas, entre ellas, la mononucleosis por citomegalovirus y por Epstein Barr virus, se asocian con linfocitopenia total y linfocitopenia T CD4+, que son transitorias y se recuperan cuando la enfermedad mejora. Una linfocitopenia grave asociada con infección crónica por virus herpes humanos y que mejore con el tratamiento de ellos, no ha sido publicada. Se describen 6 pacientes, negativos para virus de inmunodeficiencia humana, con linfocitopenia total y linfocitopenia T CD4+ graves y con manifestaciones clínicas de inmunodeficiencia celular, quienes respondieron rápidamente al tratamiento con ganciclovir o valganciclovir. Es importante considerar la infección crónica por virus herpes humanos en el diagnóstico diferencial de la etiología de la linfocitopenia T CD4+ en individuos no infectados por el virus de inmunodeficiencia humana, para iniciar un tratamiento efectivo de los pacientes y determinar en futuros estudios el impacto de la infección crónica por herpes virus en la salud humana.

Early HHV-6 replication is associated with morbidity non-related to CMV infection after kidney transplantation

Human herpesvirus type 6-(HHV-6) has been associated with morbidity after liver transplantation. OBJECTIVE: The aim of this study was to determine the HHV-6 seroprevalence among donor-recipient pairs, analyze the incidence of early active infection, its clinical manifestation, interaction with CMV, and the related morbidity in the first year after kidney transplantation. METHODS: 46 donor-recipient pairs had IgG evaluated by ELISA before transplantation: HHV-6(Pambio - USA) and CMV-(Roche - USA). A frozen whole blood sample collected weekly (from the 1st to the 6th week) was retrospectively tested for HHV-6 viral load (VL) determination by real time quantitative PCR (qPCR, Nanogen - Italy). Patients were preemptively surveyed for CMV by pp65 antigenemia (Ag, APAAP, immunohistochemistry, Biotest - Germany) from the 4th to the 12th week after transplantation. Active infection was defined as qPCR-HHV6+ (viral-load/mL-VL) and Ag+ (+cells/100.000 granulocytes), for HHV-6 and CMV, respectively. DCMV was defined as simultaneous positive antigenemia and suggestive signs/symptoms. Concerning +qPCR-HHV6, associated factors, clinical manifestation, interaction with CMV and morbidity were searched. RESULTS: Pre-transplant HHV-6 seroprevalence was significantly higher among kidney recipients compared to their donors (82.6x54.8%; p = 0.005 [3.9 (1.4-10.4)]). Active infection by this virus occurred in 26.1% (12/46), with no association with previous IgG (p = 0.412). Median VL was 125 copies/mL (53-11.264), and the median Ag was 21 +cells (2-740). There was no association between HHV-6 and CMV activation after transplantation (p = 0.441), neither concerning DCMV (p = 0.596). Median highest Ag+ and days of ganciclovir treatment were similar between qPCR-HHV6 + or - (p = 0.206 and p = 0.124, respectively). qPCR-HHV6+ was associated with higher incidence of bacterial (p = 0.009) and fungal (p = 0.001) infections, and higher number (p = 0.001) of hospital admission and longer duration of hospitalization over the first 6 and 12 months post-transplantation (p = 0.033 and p = 0.001). CONCLUSION: Latent HHV-6 infection is more common among recipients than donors before transplantation. Early active infection by this pathogen after transplantation does not increase DCMV incidence or severity during the first 3 months of follow-up. However, early HHV-6 replication is associated with other infections and hospitalizations in the first year.

Drug-induced hypersensitivity syndrome with human herpesvirus-6 reactivation.

A 45-year-old man, on carbamazepine for the past 3 months, was referred as a case of atypical measles. On examination, he had high-grade fever, generalized itchy rash, cough, vomiting and jaundice. A provisional diagnosis of drug hypersensitivity syndrome to carbamazepine was made with a differential diagnosis of viral exanthema with systemic complications. Laboratory investigations revealed leukocytosis with eosnophilia and elevated liver enzymes. Real-time multiplex polymerase chain reaction (PCR) on throat swab and blood was suggestive of human herpesvirus-6 (HHV-6). Measles was ruled out by PCR and serology. The diagnosis of drug-induced hypersensitivity syndrome (DIHS) was confirmed, which could explain all the features manifested by the patient. HHV-6 infects almost all humans by age 2 years. It infects and replicates in CD4 T lymphocytes and establishes latency in human peripheral blood monocytes or macrophages and early bone marrow progenitors. In DIHS, allergic reaction to the causative drug stimulates T cells, which leads to reactivation of the herpesvirus genome. DIHS is treated by withdrawal of the culprit drug and administration of systemic steroids. Our patient responded well to steroids and HHV-6 was negative on repeat real-time multiplex PCR at the end of treatment.

Recent progress of elucidating the mechanisms of drug hypersensitivity

Recent technical approaches to investigating drug hypersensitivity have provided a great deal of information to solve the mechanisms that remain poorly understood. First, immunological investigations and in silico analysis have revealed that a novel interaction between T cells and antigen-presenting cells, namely the pharmacological interaction concept, is involved in drug recognition and the hapten theory. Second, progress in immunology has provided a new concept of CD4+ T cell subsets. Th17 cells have proven to be a critical player in acute generalized exanthematous pustulosis. Our recent findings suggest that this subset might contribute to the pathogenesis of Stevens-Johnson syndrome/toxic epidermal necrolysis. Third, alarmins, molecules associated with innate immunity, are also associated with exaggeration and the persistence of severe drug hypersensitivity. The latest innovative techniques are providing a new landscape to examine drug hypersensitivity.

Detection of Human Herpesvirus-6 (HHV-6) in Cerebrospinal Fluid of a Patient with Fatal Status Epilepticus / 대한소아신경학회지

Human herpesvirus-6 (HHV-6) often causes mild illnesses, but is rarely associated with encephalitis or other fatal neurological conditions. We report a girl who died of a intractable status epilepticus from HHV-6. A 14-month-old girl presented with focal motor seizures in right extremities evolving to generalized convulsive status epilepticus. She had a history of mild diarrhea for 4 days and high fever for 2 days. Although she was treated with lorazepam, phenytoin, phenobarbital, and continuous midazolam infusion, generalized seizures continued for 3 hours after arrival. She became seizure free, but remained unconscious and ended up to death at the 44 days of hospitalization. The CSF HHV-6 DNA PCR turned out to be positive.