Efficacy and safety of ketamine for pediatric and adolescent super-refractory status epilepticus and the effect of cerebral inflammatory conditions

OBJECTIVE

To investigate the short-term benefits and adverse effects of ketamine in the treatment of pediatric and adolescent super-refractory status epilepticus (SRSE), with a focus on the inflammatory etiology.

METHODS

This retrospective observational cohort study included a consecutive series of 18 pediatric to adolescent patients with SRSE admitted between 2008 and 2023 and treated with ketamine. Seizure frequency per hour before and after ketamine administration and response rate were calculated. Neurological decline, catecholamine administration, and adverse effects were also assessed. The patients were divided into inflammatory and non-inflammatory etiology groups.

RESULTS

The median age at SRSE onset was 1 year 5 months (range: 11 days-24 years), and 78% of the patients were male individuals. The median duration of treatment was 7.5 days (interquartile range: 2.8-15.5 days). Fifteen (83%) patients achieved >50% seizure reduction. The median seizure frequency before and after ketamine treatment was 5.9 and 0.9, respectively, showing a significant reduction in seizure frequency (p < 0.0001). Ten patients had inflammatory etiologies including bacterial meningitis (n = 2), viral encephalitis (n = 3), and febrile infection related epilepsy syndrome (n = 5). The inflammatory etiology group required a longer treatment duration (p = 0.0453) and showed lower seizure reduction (p = 0.0264), lower response rate (p = 0.0044), and higher neurological decline (p = 0.0003) than the non-inflammatory etiology group. Three (17%) patients experienced transient adverse events requiring intervention within 24 h of initiating ketamine administration.

CONCLUSIONS

Ketamine administration was associated with fewer serious adverse events and a reduced seizure frequency. Additionally, inflammatory conditions may weaken the efficacy of ketamine in patients with SRSE.

COVID-19 relapse associated with SARS-CoV-2 evasion from CD4+ T-cell recognition in an agammaglobulinemia patient

A 25-year-old patient with a primary immunodeficiency lacking immunoglobulin production experienced a relapse after a 239-day period of persistent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Viral genetic sequencing demonstrated that SARS-CoV-2 had evolved during the infection period, with at least five mutations associated with host cellular immune recognition. Among them, the T32I mutation in ORF3a was found to evade recognition by CD4⁺ T cells. The virus found after relapse showed an increased proliferative capacity in vitro. SARS-CoV-2 may have evolved to evade recognition by CD4⁺ T cells and increased in its proliferative capacity during the persistent infection, likely leading to relapse. These mutations may further affect viral clearance in hosts with similar types of human leukocyte antigens. The early elimination of SARS-CoV-2 in immunocompromised patients is therefore important not only to improve the condition of patients but also to prevent the emergence of mutants that threaten public health.

Acute and Postacute Clinical Characteristics of Coronavirus Disease 2019 in Children in Japan

BACKGROUND

The clinical features of coronavirus disease 2019 (COVID-19) in children have been changing because of the emergence and rapid spread of variants of concern (VOC). The increase in cases infected with VOC has brought concern with persistent symptoms after COVID-19 in children. This survey aimed to analyze the clinical manifestations and persistent symptoms of pediatric COVID-19 cases in Japan.

METHODS

We analyzed the clinical manifestations of pediatric COVID-19 cases reported between February 2020 and April 2022 in Japan, using a dedicated database updated voluntarily by the members of the Japan Pediatric Society. Using the same database, we also analyzed persistent symptoms after COVID-19 in children who were diagnosed between February 2020 and November 2021.

RESULTS

A total of 5411 and 1697 pediatric COVID-19 cases were included for analyzing clinical manifestations and persistent symptoms, respectively. During the Omicron variant predominant period, the percentage of patients with seizures increased to 13.4% and 7.4% in patient groups 1-4 and 5-11 years of age, respectively, compared with the pre-Delta (1.3%, 0.4%) or Delta period (3.1%, 0.0%). Persistent and present symptoms after 28 days of COVID-19 onset were reported in 55 (3.2%).

CONCLUSIONS

Our survey showed that the rate of symptomatic pediatric COVID-19 cases increased gradually, especially during the Omicron variant predominant period, and a certain percentage of pediatric cases had persistent symptoms. Certain percentages of pediatric COVID-19 patients had severe complications or prolonged symptoms. Further studies are needed to follow such patients.

Life-threatening pneumothorax after release from isolation with COVID-19 pneumonia

Pneumothorax was previously considered as a complication of severe coronavirus disease 2019 (COVID-19) pneumonia. However, it is now known that pneumothorax can develop in other cases. Here, we describe the case of a patient who developed tension pneumothorax after release from isolation from COVID-19 pneumonia. The patient was admitted to our hospital with severe COVID-19 pneumonia on the 10th day after onset. Ventilatory management was carried out on the first day of admission; however, the patient was weaned off the next day. The treatment course was uneventful. On the morning of discharge from the hospital, the patient experienced sudden dyspnea. Chest radiography revealed a large left-tension pneumothorax with a mediastinal shift to the right. As this finding required immediate attention, a chest tube was inserted. Chest computed tomography (CT) showed an airspace in the left thoracic cavity and subpleural thin-walled cystic lesions, such as bullae in the left lobe. One month later, chest CT showed resolution of the cystic lesions. The development of pneumothorax in COVID-19 pneumonia should be considered not only in cases of severe illness, but also after release from isolation. Recently, revisions to measures against COVID-19 have been considered worldwide, including shortening of the isolation period and reviewing the identification of all cases. This is an educational report demonstrating that life-threatening pneumothorax may develop after release from isolation due to COVID-19 pneumonia.

Comparative whole-genome sequence analysis of a BoNT/B5-producing Clostridium botulinum isolate from an infant botulism case of unknown source in Osaka, Japan

A case of infant botulism of unknown origin, not involved in honey consumption, occurred in Osaka, Japan in 2020. A Clostridium botulinum type B strain named Osaka2020 was isolated from a stool sample of the patient. To clarify the epidemiology of the case, we performed whole-genome sequencing (WGS) of the isolate and compared it with strains from other sources. WGS analysis revealed that isolate Osaka2020 was classified into ST133 of a new sequence type, B5 subtype, and its toxin gene was encoded in a ∼274 kb plasmid. This plasmid was closely related to the pCLJ plasmid from strain 657Ba in the USA, reported to be conjugatively transferable to other strains. Moreover, isolate Osaka2020 also possesses another smaller plasmid that was common with some type A(B) infant botulism isolates in Japan. The phylogenetic tree from whole-genome SNP analysis showed that isolate Osaka2020 was the most closely related to a type B infant botulism isolate that occurred in Japan 10 years ago. Although no epidemiological connection among the two cases was confirmed, there is possibility that the cases are attributed to common causes such as some environmental substance.

A case of bilateral limbic and recurrent unilateral cortical encephalitis with anti-myelin oligodendrocyte glycoprotein antibody positivity

BACKGROUND

Anti-myelin oligodendrocyte glycoprotein (MOG) antibody can be detected not only in acute disseminated encephalomyelitis or optic neuritis but also in limbic or cortical encephalitis. However, no previous reports have demonstrated a relapsing case of these two types of encephalitis.

CASE REPORT

An 11-year-old girl presented with fever, headache, abnormal behavior, focal impaired awareness seizures (FIAS) on the left side, and MRI hyperintensities in the bilateral amygdala, hippocampus, and right posterior temporal cortex. The symptoms were alleviated with two courses of intravenous methylprednisolone (IVMP) and one course of immunoglobulin. At 16 years of age, the patient returned with left-sided headache and MRI hyperintensities in the left temporal, parietal, and insular cortices, which improved after 3 courses of IVMP. Oral prednisolone (PSL) was tapered over 6 months, when FIAS reappeared on the right side of the body. MRI showed recurrence in the same regions as in the second episode. She received 3 courses of IVMP, followed by gradually tapered PSL without relapse for 1.5 year. Anti-MOG antibodies were positive in both serum and the cerebrospinal fluid prior to treatment in all three episodes.

CONCLUSION

Our results revealed that anti-MOG antibody-related bilateral limbic and unilateral cortical encephalitis can manifest with a variety of phenotypes over time in the same patient.

Longitudinal electroencephalogram findings predict acute neurological and epilepsy outcomes in patients with hemorrhagic shock and encephalopathy syndrome

OBJECTIVE

Hemorrhagic shock and encephalopathy syndrome (HSES) is a severe subtype of acute encephalopathy with a poor prognosis. The association between electroencephalogram (EEG) findings and neurological outcomes in patients with HSES, including the onset of epilepsy, remains unclear.

METHODS

Thirty-two children with HSES registered in a database of Osaka City General Hospital between 2003 and 2018 were included in this study. The EEG findings which consisted of continuity, reactivity, state change, voltage, rhythmic and periodic patterns, and electrographic or electroclinical seizures, in the onset phase were evaluated for patient outcome. Patients who avoided acute death were investigated for epilepsy by a longitudinal EEG. Seizure types were determined by ictal video recordings.

RESULTS

We analyzed EEG findings in the onset phase of 30 patients. Severely to extremely abnormal EEG pattern (deteriorated continuity more than discontinuous pattern, presence of generalized abnormal low voltage slow wave, and presence of generalized rhythmic and periodic patterns) in the onset phase correlated with poor outcome (p = 0.0024). Subsequently, 9/23 patients (39%) developed epilepsy, of which a total of eight had epileptic spasms. A significant correlation between interictal epileptic discharges and the development of epilepsy was observed as early as within three months (p = 0.0003).

CONCLUSIONS

EEG pattern in the onset phase may be useful to predict the neurological prognosis in the acute stage. Moreover, this study demonstrated that longitudinal EEG findings after the acute phase of HSES were significantly related to the development of epilepsy. EEG findings are useful for predicting acute prognosis and epilepsy in patients with HSES.

The clinical characteristics of pediatric coronavirus disease 2019 in 2020 in Japan

BACKGROUND

The COVID-19 pandemic has affected the lives of people of all ages. Most reports on pediatric cases suggest that children experience fewer and milder symptoms than do adults. This is the first nationwide study in Japan focusing on pediatric cases reported by pediatricians, including cases with no or mild symptoms.

METHODS

We analyzed the epidemiological and clinical characteristics and transmission patterns of 840 pediatric (<16 years old) COVID-19 cases reported between February and December 2020 in Japan, using a dedicated database which was maintained voluntarily by members of the Japan Pediatric Society.

RESULTS

Almost half of the patients (47.7%) were asymptomatic, while most of the others presented mild symptoms. At the time of admission or first outpatient clinic visit, 84.0% of the cases were afebrile (<37.5°C). In total, 609 cases (72.5%) were exposed to COVID-19-positive household members. We analyzed the influence of nationwide school closures that were introduced in March 2020 on COVID-19 transmission routes among children in Japan. Transmission within households occurred most frequently, with no significant difference between the periods before and after declaring nationwide school closures (70.9% and 74.5%, respectively).

CONCLUSIONS

COVID-19 symptoms in children are less severe than those in adults. School closure appeared to have a limited effect on transmission. Controlling household transmission from adult family members is the most important measure for prevention of COVID-19 among children.

Intrathecal dexamethasone therapy for febrile infection-related epilepsy syndrome

OBJECTIVE

Increasing reports suggest a role for immunological mechanisms in febrile infection-related epilepsy syndrome (FIRES). The objective of this study was to elucidate the efficacy and safety of intrathecal dexamethasone therapy (IT-DEX).

METHODS

We assessed six pediatric patients with FIRES who were administered add-on IT-DEX in the acute (n = 5) and chronic (n = 1) phases. We evaluated clinical courses and prognosis. We measured cytokines/chemokines in cerebrospinal fluid (CSF) from FIRES patients at several points, including pre- and post-IT-DEX, and compared them with control patients with chronic epilepsy (n = 12, for cytokines/chemokines) or with noninflammatory neurological disease (NIND, n = 13, for neopterin).

RESULTS

Anesthesia was weaned after a median of 5.5 days from IT-DEX initiation (n = 6). There was a positive correlation between the duration from the disease onset to the introduction of IT-DEX and the length of ICU stay and the duration of mechanical ventilation. No patient experienced severe adverse events. Seizure spreading and background activities on electroencephalography were improved after IT-DEX in all patients. The levels of CXCL10, CXCL9, IFN-γ, and neopterin at pre-IT-DEX were significantly elevated compared to levels in epilepsy controls, and CXCL10 and neopterin were significantly decreased post-IT-DEX, but were still higher compared to patients with chronic epilepsy. IL-6, IL-8, and IL-1β were significantly elevated before IT-DEX compared to epilepsy controls, though there was no significant decrease post-treatment.

INTERPRETATION

IT-DEX represents a therapeutic option for patients with FIRES that could shorten the duration of the critical stage of the disease. The effect of IT-DEX on FIRES might include cytokine-independent mechanisms.

DWI scoring system for prognosis of acute encephalopathy with biphasic seizures and late reduced diffusion

PURPOSE

The aim of this study was to predict neurological outcomes for acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) using diffusion-weighted imaging (DWI), and assess relationships between anatomical sites of lesions and their outcomes.

MATERIALS AND METHODS

We assessed DWI abnormalities and neurological outcomes in 30 patients with AESD, and classified patients into severe and non-severe groups according to their neurological outcomes. We also established a DWI scoring system as follows: zero for normal, and one for lesion at each location. Differences between the severe and non-severe groups were examined, and receiver operating characteristic (ROC) curve analysis was performed.

RESULTS

Nine (30%) patients were classified into the severe group. On DWI, patients in the severe group were more likely to have temporal lobe (P = 0.014), perirolandic (P = 0.008), and corpus callosum (P = 0.0008) lesions than those in the non-severe group. The total DWI scores were significantly higher in the severe group than those in the non-severe group (P = 0.0002). ROC curve showed an area under the curve of 0.929, with a cutoff value of five, sensitivity of 88.9%, and specificity of 81.0%.

CONCLUSION

Patients with severe AESD had more extensive DWI abnormalities than those with non-severe AESD. Our DWI scoring system may be useful for the prediction of outcomes of AESD. Widespread lesions seemed to have stronger influence on outcomes than each lesion location.

An unusual manifestation of Sjögren syndrome encephalitis

Sjögren syndrome (SS) is a systemic inflammatory and autoimmune disease characterized by systemic disorders of the exocrine glands, predominantly the salivary and lacrimal glands. Here, we report a 4-year-old boy who presented with the repetition of generalized tonic-clonic seizures for 1-2 min. Initially, he was diagnosed with idiopathic autoimmune encephalitis and was treated with steroids. He was eventually diagnosed with SS based on the examination results, such as inflammatory cell infiltration into the minor salivary glands and positive serum anti-SSA/Ro antibody. Although central nervous system complications are rare in pediatric SS, this condition should be considered in the differential diagnosis when a patient presents with idiopathic autoimmune encephalitis of unknown cause. Furthermore, SS can occur in relatively young children and can present without imaging abnormalities.

Distinct genetic clades of enterovirus D68 detected in 2010, 2013, and 2015 in Osaka City, Japan

The first upsurge of enterovirus D68 (EV-D68), a causative agent of acute respiratory infections (ARIs), in Japan was reported in Osaka City in 2010. In this study, which began in 2010, we surveyed EV-D68 in children with ARIs and analyzed sequences of EV-D68 strains detected. Real-time PCR of 19 respiratory viruses or subtypes of viruses, including enterovirus, was performed on 2,215 specimens from ARI patients (<10 years of age) collected between November 2010 and December 2015 in Osaka City, Japan. EV-D68 was identified in 18 enterovirus-positive specimens (n = 4 in 2013, n = 1 in 2014, and n = 13 in 2015) by analysis of viral protein 1 (VP1) or VP4 sequences, followed by a BLAST search for similar sequences. All EV-D68 strains were detected between June and October (summer to autumn), except for one strain detected in 2014. A phylogenetic analysis of available VP1 sequences revealed that the Osaka strains detected in 2010, 2013, and 2015 belonged to distinct clusters (Clades C, A, and B [Subclade B3], respectively). Comparison of the 5' untranslated regions of these viruses showed that Osaka strains in Clades A, B (Subclade B3), and C commonly had deletions at nucleotide positions 681-703 corresponding to the prototype Fermon strain. Clades B and C had deletions from nucleotide positions 713-724. Since the EV-D68 epidemic in 2010, EV-D68 re-emerged in Osaka City, Japan, in 2013 and 2015. Results of this study indicate that distinct clades of EV-D68 contributed to re-emergences of this virus in 2010, 2013, and 2015 in this limited region.

Non-invasive diagnosis of cutaneous leishmaniasis by the direct boil loop-mediated isothermal amplification method and MinION™ nanopore sequencing

Cutaneous leishmaniasis (CL) is gaining attention as a public health problem. We present two cases of CL imported from Syria and Venezuela in Japan. We diagnosed them as CL non-invasively by the direct boil loop-mediated isothermal amplification method and an innovative sequencing method using the MinION™ sequencer. This report demonstrates that our procedure could be useful for the diagnosis of CL in both clinical and epidemiological settings.

Characteristic neuroradiologic features in hemorrhagic shock and encephalopathy syndrome

Hemorrhagic shock and encephalopathy syndrome is a devastating disease, but the pathogenesis remains unclear. The aim of this study was to examine the usefulness of neuroimaging in establishing a diagnosis and elucidating the pathogenesis. We analyzed the neuroradiologic features of 22 patients who fulfilled the Levin criteria. All patients underwent brain computed tomography (CT), and 14 patients underwent brain magnetic resonance imaging (MRI) including diffusion-weighted imaging in 10 patients. Initial CT showed normal findings in 14 of 18 (78%) patients, but subsequently hypodensities appeared in bilateral watershed zones and progressed to whole brain edema. MRI revealed cytotoxic edema, showing hyperintensities in bilateral watershed zones on diffusion-weighted imaging with a low apparent diffusion coefficient. Serial neuroimaging showed characteristic features of a widespread brain ischemic event mainly in watershed zones in hemorrhagic shock and encephalopathy syndrome.

[A clinical study on high-dose erythropoietin therapy for acute encephalopathy or encephalitis]

OBJECTIVE

We performed high-dose erythropoietin therapy (hEPO) for acute encephalopathy or encephalitis (AE), and evaluated its safety and efficacy.

METHODS

We performed hEPO in AE patients with widespread lesions demonstrated by diffusion-weighted imaging, and prospectively investigated changes in hemoglobin levels, adverse events, changes in images, and developmental quotients.

RESULTS

All four patients showed neither an increase in the hemoglobin level nor adverse event possibly related to hEPO. One patient with acute encephalitis showed resolution of the lesion and normal developmental quotient. Two patients who had acute encephalopathy with febrile convulsive status epilepticus showed mild cerebral atrophy in the recovery phase;one had a normal developmental quotient. The patient with acute necrotizing encephalopathy including a brainstem lesion avoided acute-phase death.

CONCLUSION

Two patients showed no sequelae despite images indicating widespread abnormality. hEPO could be performed safely in patients with AE, however further trials are necessary concerning its efficacy.

[Clinical evaluation of six patients with anti-NMDAR encephalitis]

OBJECTIVE

We examined the clinical course and the prognosis of patients with anti-NMDAR encephalitis.

METHODS

We retrospectively evaluated the patients who has distinctive clinical features as anti-NMDAR encephalitis based on their medical records.

RESULTS

There were two male and four female patients with anti-NMDAR encephalitis. They were aged between 13 and 16 years. One of the six, 14 years female patient was negative for anti-NMDAR antibody. All four female patients with anti-NMDAR encephalitis had an ovarian tumor. Neurocognitive dysfunction and epilepsy remained in one female patient with right temporal lobe lesion and one male patient with celebellar abnormalities had mild mental impairment. In three patients including two patients who were examined abdominal MRI for the first time after recovery from the encephalitis, overian tumors became apparent during follow-up. In one of other patients, overian tumors had a tendency to increase in size after recovery.

CONCLUSION

Sequellae were seen in two cases that have abnormalities in brain MRI. As to ovarian tumor, it was considered to be necessary to checkup pelvic MRI for at least four years after the onset of encephalitis.

[Salmonella]

Nontyphoidal salmonella causes infectious gastroenteritis, and sometimes causes bacteremia and meningitis. Gastroenteritis associated with nontyphoidal salmonella, in which fever, diarrhea, vomiting and abdominal cramps, is a common disease. The major way of transmittion is food of animal origin, for example egg. That is the reason why precausion is so important such as wash hands before cooking, avoid eating raw egg and wash the cooking utensils after contact raw foods. In this report, I presented the rare severe case of encephalitis caused by salmonella infection.

[Clinical study of patients undergoing paperless electroencephalography in emergency room]

Fifty-eight patients who visited the emergency room of our center with febrile convulsions and impaired consciousness, and underwent paperless electroencephalography soon after arrival. They consisted of 25 male and 33 female children, ranging in age from 5 months to 15 years and 4 months, with a mean age of 4 years and 10 months. The final diagnoses were poor responsiveness associated with fever and febrile delirium in 5 patients, febrile convulsions in 26, encephalitis/encephalopathy in 24, convulsions associated with mild gastroenteritis in 2, and aseptic meningitis in 1. The appearance of spindle wave within 24 hours after admission was considered to be a favorable prognostic factor, whereas generalized high-amplitude delta waves without fast-wave components and dysrhythmic flat basic waves were considered poor prognostic factors. We conclude that bed-side paperless electroencephalography is useful for the evaluation of changes in the brain function and course of treatment.

Human herpesvirus 6 (HHV-6) is transmitted from parent to child in an integrated form and characterization of cases with chromosomally integrated HHV-6 DNA

We obtained 7,566 peripheral blood mononuclear cell (PBMC) samples from 2,332 individuals and screened them for human herpesvirus infection. We identified five individuals who persistently harbored high copy numbers of human herpesvirus 6 (HHV-6) DNA in their PBMCs. HHV-6 DNA was also detected in other somatic tissues of these individuals. Five additional cases were identified among their family members. For two of these families, chromosomally integrated HHV-6 DNA (CIHHV-6) was detected in the PBMCs by fluorescence in situ hybridization. The prevalence of CIHHV-6 among all the subjects was 0.21%. The HHV-6 DNA was variant B in four families and variant A in one family. Antibodies to immediate early antigen and glycoprotein B were detected in 57 and 14% of individuals with CIHHV-6 and in 0 and 60% of healthy volunteers without CIHHV-6, respectively. HHV-6 could not be isolated from PBMCs with CIHHV-6. These cases shared no clinical features, and included three healthy individuals. Our data suggest that CIHHV-6 is rare but detectable in the general population and that hereditary transmission is one of the routes of HHV-6 transmission.

Enhancement of immunity against VZV by giving live varicella vaccine to the elderly assessed by VZV skin test and IAHA, gpELISA antibody assay

The enhancement of immunity against varicella-zoster vaccine (VZV) by subcutaneous injection of a live varicella vaccine was assessed by the VZV skin test for cell-mediated immunity (CMI), and immunoadherence hemagglutination assay (IAHA) and gpELISA antibody assays in the elderly people of 50-79 years of age. A total of 127 subjects were examined: 79 aged 50-59, 25 aged 60-69, and 25 aged 70-79. All were seropositive by the gpELISA assay (one was seronegative in the IAHA antibody assay). In contrast, a notable decline was observed in the VZV skin test with increasing age. Negative reaction was observed in 16/79 (20.2%) of the subjects in their 50s, 12/25 (48.0%) in their 60s and 14/25 (56.0%) in the 70s. After the vaccination, the results of the VZV skin test changed from negative to positive in 15/16 (91.8%) of subjects in their 50s, 11/12 (91.7%) in their 60s and 12/14 (85.7%) in their 70s. The mean antibody titer in the IAHA and the gpELISA increased approximately two-fold after the vaccination in each group. Immunity to VZV in 35 elderly subjects who were vaccinated previously was followed up for 4 years. All were positive by the VZV skin test after the previous vaccination. After 4 years, 31 (88.6%) were positive by the skin test, 4 were negative and became positive after revaccination. Although this study was uncontrolled open study, the results suggest that administering live varicella vaccine to the elderly is effective for enhancing immunity, particularly CMI to VZV.

Recognition of a novel stage of betaherpesvirus latency in human herpesvirus 6

Latency-associated transcripts of human herpesvirus 6 (H6LTs) (K. Kondo et al. J. Virol. 76:4145-4151, 2002) were maximally expressed at a fairly stable intermediate stage between latency and reactivation both in vivo and in vitro. H6LTs functioned as sources of immediate-early protein 1 at this stage, which up-regulated the viral reactivation.

Human herpesvirus 6B infection of the large intestine of patients with diarrhea

Four patients had severe diarrhea after undergoing stem cell transplantation. Human herpesvirus 6B (HHV-6B) DNA was detected in large intestine tissue specimens and in peripheral blood mononuclear cells. In situ hybridization was positive for HHV-6B DNA in the nuclei of goblet cells and, sometimes, in the histiocytes in the submucous region of the large intestine, which suggests that HHV-6B may infect and reactivate in these cells.

High incidence of human herpesvirus 6 infection with a high viral load in cord blood stem cell transplant recipients

Human herpesvirus 6 (HHV-6) infection in recipients of cord blood stem cell transplants (CBSCTs) was estimated by semiquantitative and real-time quantitative polymerase chain reaction (PCR) and reverse-transcription PCR. Of the CBSCT recipients, 7 (70%) of 10 had active HHV-6 infection after transplantation, and all 7 were inferred from their age to have already had a primary infection. Because HHV-6 DNA is seldom detected in cord blood, these cases were considered likely to represent reactivation. In contrast, the 3 patients without HHV-6 infection were all believed to be naive regarding HHV-6 primary infection because of their age and the results of PCR assays given before the transplantation procedure. The incidence of HHV-6 infection after transplantation was significantly higher (P <.05) than after bone marrow (BM) transplantation and peripheral blood stem cell (PBSC) transplantation, when recipients without primary HHV-6 infection prior to transplantation were excluded (CBSCT, 100%; BMT/PBSCT, 56.3%). Real-time PCR revealed a higher level of viral DNA in the peripheral blood mononuclear cells from CBSCT recipients than from BMT/PBSCT recipients or patients with exanthem subitum (P <.05). HHV-6 mRNA of the U79/80 gene was also detected by reverse-transcription PCR in all analyzed patients with HHV-6 infection. Its detection was correlated with the emergence of viral DNA in the plasma and symptoms such as fever and rash. Thus, HHV-6 infection was more frequent and the viral load was higher in CBSCT recipients with prior primary infection.

Strong interaction between human herpesvirus 6 and peripheral blood monocytes/macrophages during acute infection

Human herpesvirus 6 (HHV-6) encodes a viral chemokine and chemokine receptors that may modify the functions of monocytes/macrophages (MO/M phi) during productive HHV-6 infection. The interactions between HHV-6 and MO/M phi during acute infection, however, remain poorly understood. In this study, we investigated the tropism of HHV-6 in peripheral blood mononuclear cells (PBMCs) during acute infection. We detected 637 +/- 273 copies of viral DNA in 10(4) MO/M phi. in contrast, in 10(4) CD4+ T cells, which have been reported to be viral carriers during the acute infection of HHV-6, we found only 115 +/- 42 copies of viral DNA. Consistent with these data, virus was isolated from MO/M phi an order of magnitude more frequently than from CD4+ T cells. Viral mRNA U79/80, which indicates viral replication, was detectable in the MO/M phi. In addition, the mRNAs that encode viral chemokine receptors U12 and U51, which may modify the function of MO/M phi, were expressed in the cells. Therefore, productively infected MO/M phi may be the dominant cell population that is responsible for HHV-6 viremia during acute HHV-6 infection. The strong interaction of HHV-6 with MO/M phi may be partly responsible for the pathogenesis of this virus.

Foscarnet therapy for ganciclovir-resistant cytomegalovirus retinitis after stem cell transplantation: effective monitoring of CMV infection by quantitative analysis of CMV mRNA

We report three pediatric patients with ganciclovir-resistant cytomegalovirus (CMV) retinitis who were successfully treated with foscarnet. The patients were recipients of hematopoietic stem cell transplantation (SCT) from HLA-mismatched donors. Because these patients had developed or experienced progressive CMV retinitis during ganciclovir therapy, they received foscarnet therapy at 60 mg/kg every 8 h. Their retinitis resolved promptly after initiating foscarnet therapy, suggesting foscarnet's effectiveness in treating ganciclovir-resistant CMV infection. The amount of CMV mRNA was quantitatively measured using an NASBA technique, which amplified the beta2.7 transcripts specific for CMV replication. This technique was useful for monitoring disease activity in a more rapid and sensitive manner than the PCR assay for CMV DNA.

Epidemiological study of human herpesvirus-6 and human herpesvirus-7 in pityriasis rosea

BACKGROUND

Pityriasis rosea (PR) is a common papulosquamous skin disorder that is suspected to have an infectious aetiology.

OBJECTIVES

We aimed to study the role of human herpesvirus (HHV)-7 and HHV-6 in the pathogenesis of PR.

METHODS

We performed seroepidemiological studies (indirect immunofluorescence test) and polymerase chain reaction (PCR) analysis for HHV-6 and HHV-7 in patients with PR. Seventy-two serum samples and 37 samples of peripheral blood mononuclear cells (PBMC) from 44 patients with PR were obtained. Twenty-five patients with other skin disorders such as drug eruption, urticaria or herpes zoster were studied as controls in the PCR analysis.

RESULTS

HHV-7 DNA was detected in 13 of 30 (43%) samples of PBMC of the patients with PR and 14 of 25 (56%) samples of PBMC of controls. HHV-6 DNA was detected in six of 29 (21%) patients with PR and nine of 23 (39%) controls. Thus there was no difference in the prevalence of HHV-6 or HHV-7 in PBMC between patients with PR and those with other skin disorders. In the seroepidemiological study, two cases of at least a fourfold rise in titre and five cases of a fourfold decrease in titre to HHV-7 antibody, and two cases of a fourfold rise in titre and two cases of a fourfold decrease in titre to HHV-6 antibody, were observed in 24 patients with PR. This seroepidemiological study revealed antibody responses consistent with active infection in several PR patients, but the greater proportion of the patients had no definite increase in the antibody titres.

CONCLUSIONS

We conclude that HHV-7 and HHV-6 may play a part in some patients with PR, but that other causative agents may exist. Further analyses are needed to determine the causative agents of PR.

[Infantile T cell acute lymphoblastic leukemia complicated by thrombotic microangiopathy and human herpes virus 6 infection after allogeneic peripheral blood stem cell transplantation using CD34-positive cells]

We report on a 19-month-old boy with refractory T-cell acute lymphoblastic leukemia who underwent allogeneic peripheral blood stem cell transplantation using positively selected CD34 cells from his HLA two-loci mismatched mother. The conditioning regimen consisted of busulfan (140 mg/m2/d for 2 days), total body irradiation (12 Gy) and melphalan (210 mg/m2). The patient received cyclosporin A for graft-versus-host disease (GVHD) prophylaxis. The CD34-positive cells were separated using an immunomagnetic cell-separation system (Isolex 50). The number of infused CD34-positive cells was 4.4 x 10(6)/kg. Successful engraftment was confirmed on day 14 by fluorescent in situ hybridization of X chromosomes. The patient experienced severe diarrhea due to thrombotic microangiopathy (TMA) following acute GVHD, and died on day 71 of human herpes virus type 6 pneumonitis. Stem cell transplantation using CD34 positively selected cells from HLA-mismatched related donors may be a useful treatment with low incidence of severe GVHD, but many problems remain to be overcome, including severe viral infections and TMA.

Pseudotumorous enlargement of the paracaval portion of the caudate lobe: a report of two cases with CT and MR appearance

The computed tomographic (CT) and magnetic resonance appearance of pseudotumorous enlargement of the paracaval portion (PCP) of the caudate lobe of the liver are presented in two cirrhotic patients. The enlarged PCP was hyperattenuated on precontrast CT and hyperintense on T1-weighted images. The middle and right hepatic veins were displaced around the PCP. The presence of a portal vein branch penetrating the center of the enlarged PCP was important to distinguish it from other hepatic masses in the two patients.

High-resolution MR imaging evaluation of hepatocellular carcinoma

PURPOSE

To determine the utility of high-resolution MR imaging for hepatocellular carcinoma.

MATERIALS AND METHODS

High-resolution MR images with a 512 matrix in a right to left frequency encoding direction were obtained in 20 consecutive patients with known or suspected hepatocellular carcinoma (HCC). Six series of breath-hold images of the entire liver [T1- and T2-weighted fast spin echo sequences, T1-weighted fast low-angle shot gradient echo sequence and three-phased contrast-enhanced dynamic study using the latter) were obtained using a phased-array multicoil.

RESULTS

HCC was depicted in 15 patients on the MR images, and the diagnosis was confirmed at pathology in 13 and at imaging in the other two. In the remaining five patients, HCC was correctly ruled out with MR imaging.

CONCLUSION

High-resolution MR imaging is a promising method in the evaluation of HCC.

[Metabolism of 99mTc-ethyl cysteinate dimer (99mTc-ECD) in blood--mainly in vitro]

Metabolism of 99mTc-ethyl cysteinate dimer (99mTc-ECD) in blood was studied mainly in vitro. When 99mTc-ECD was mixed with blood taken from 12 subjects, the octanol extraction ratio of ECD (y) decreased rapidly and the octanol extraction ratio-time profile well fitted a monoexponential curve (y = Ae-kt/1000, A, k: constant, t: time after mixing). The k value and hematocrit (Ht) were significantly correlated (k = 0.376Ht-3.27, r = 0.897, p less than 0.001), therefore, it was suggested that the majority of the enzyme which dissolves ECD exists in red blood cells. When ECD was mixed with blood, there were more hydrophilic products of ECD in plasma than those generated by the enzyme in plasma. In vivo input function of 99mTc-ECD was calculated by arterial blood sampling and octanol extraction. The duration of effective input was relatively short, which was attributed to rapid decrease of octanol extraction ratio in vivo.

[67Ga scintigraphic study of a case of recurrent extra-abdominal desmoid tumor]

A case of extra-abdominal desmoid tumor was studied with 67Ga scintigraphy. Extra-abdominal desmoid tumors show an aggressive clinical course with tendency of recurrence in high percentage. On 67Ga scintigraphy, our case revealed a hot spot which is useful of recurrence. 67Ga scintigraphic study was useful in searching for local and recurrence after surgery.

[Clinical evaluation of serum CEA levels in uterine cervix cancer]

Serum CEA levels were measured in the blood of 98 patients with uterine cervix cancer before, during, and after treatment to investigate the relationship among the CEA level, the extent of the disease, and recovery. The CEA level rose as the disease progressed. Although there was no significant difference in the survival rates of patients with various CEA levels, those who returned to normal levels after treatment recuperated better. There was not clear evidence that CEA levels are clinically significant. However, it can be concluded that CEA levels at pre- and post-treatment times are helpful in the early detection of disease, prognosis, and in predicting recurrence or metastasis.