Subacute sclerosing panencephalitis

CSF Interleukins-12, 17 and Interferon-γ Levels in Children with Subacute Sclerosing Panencephalitis

Subacute sclerosing panencephalitis (SSPE) is a devastating fatal condition caused by mutated measles virus. It predominantly affects children of younger age and invariably leads to mortality. Though reported rarely, the disease continues to cause significant morbidity in children. The authors conducted an observational study in which CSF was withdrawn from 24 cases of confirmed SSPE (Dyken's criteria) and interleukin levels were estimated by ELISA method. On analysis, IL-12 was significantly elevated in CSF of stage 3 SSPE patients with p value of 0.02. It was elevated in only 2 patients of stage 3 which is the major limitation of this study. No significant difference was seen in IL-17 and interferon-γ levels between different stages of SSPE in serum and CSF. This study highlights the significant elevation of IL-12 cytokine while other studied cytokines (IL-17/ IFN-γ) were not significantly altered in these patients.

Association of NOD1 and NOD2 Polymorphisms With Susceptibility to Subacute Sclerosing Panencephalitis

Background: Subacute sclerosing panencephalitis is a progressive neurodegenerative disease that is a late complication of measles infection. However, to date, the pathogenesis of subacute sclerosing panencephalitis is still not explained; both viral and host factors seem to be associated. The present study aimed to investigate the relationship between NOD1 and NOD2 gene variants and subacute sclerosing panencephalitis. Methods: The gene variants of NOD1 (rs2075820 and rs2075818) and NOD2 (R334Q and R334W) were explored in 64 subacute sclerosing panencephalitis patients and 70 controls using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Results: The frequencies of the AA genotype and A allele of rs2075820 (NOD1; c.796G>A) polymorphism were lower in patients compared with controls (P = .022 and .014, respectively). The presence of the A allele of rs2075820 may be considered as a protective factor for subacute sclerosing panencephalitis. There was a significant difference between the groups in rs2075818 (NOD1 G/C) polymorphism, and the CC genotype increased the risk of subacute sclerosing panencephalitis by 3.471-fold. The carriers of the C allele of rs2075818 (G/C) had a 1.855-fold susceptibility to subacute sclerosing panencephalitis (P = .018). The GC genotype might be associated with subacute sclerosing panencephalitis susceptibility in the patients compared with patients without having that haplotype (P = .03). Conclusions: Thus, we identified an association between subacute sclerosing panencephalitis and the rs2075820 (NOD1 G/A) and rs2075818 (NOD1 G/C) polymorphisms. These findings implicate a possible effect of this genetic polymorphism in susceptibility to subacute sclerosing panencephalitis, which needs to be confirmed in bigger populations.

IL28B, IL29 and micro-RNA 548 in subacute sclerosing panencephalitis as a rare disease

Subacute sclerosing panencephalitis (SSPE) is a progressive neurodegenerative disease which affects children and young adults, caused by a persistent infection of defective measles virus. IFN-λs (IL-28A, IL-28B and IL-29) are a group of cytokines mediating antiviral responses. It has been shown that IL-29 levels are significantly higher in infected cells with defective measles virus. IL-29 expression is thought to be regulated at post-transcriptional level and miRNA-548 family targets the 3'UTR of the IFNL1 gene. Impaired immune system has an important role as well as viral factors in SSPE. The aim of our study investigates whether IL-28B, IL-29 levels and gene polymorphisms contribute to the damaged immune response leading to the development of SSPE. Also possible association of miR-548 family with IL-29 and SSPE is explored. Frequencies of rs12979860, rs8099917, rs30461, serum levels of IL-28B, IL-29 and expression levels of miR-548b, miR-548c, miR-548i are determined at 64 SSPE patients and 68 healthy controls. Serum IL-29 levels are statistically significant higher in SSPE patients. Allele frequencies of rs8099917 are statistically significant higher in SSPE patients and resulted G allele is found to increase 2.183-fold risk of SSPE. The expression levels of miR-548b-5p, miR-548c-5p and miR-548i are found to be statistically significant higher in SSPE patients. Dramatically increased level of IL-29 seen in patient group indicates that the elevated miR-548 expression is compensatory result of the over-activated immune system response. Further studies referred to IL28, IL29 and related miRNA's will be enlightened the pathogenesis of SSPE.

Measles-induced encephalitis

Encephalitis is the most frequent neurological complication of measles virus infection. This review examines the pathophysiology of measles infection and the presentations, diagnosis and treatment of the four types of measles-induced encephalitis including primary measles encephalitis, acute post-measles encephalitis, measles inclusion body encephalitis and subacute sclerosing panencephalitis. The early symptoms of encephalitis may be non-specific and can be mistakenly attributed to a systemic infection leading to a delay in diagnosis. This review provides a summary of the symptoms that should cause health care workers to suspect measles-induced encephalitis.

Measles, mumps, rubella, and human parvovirus B19 infections and neurologic disease

While the systemic disorders associated with measles, mumps, and rubella viruses and human parvovirus B19 tend to be mild, each virus can produce potentially life-threatening neurologic disease in human hosts, especially when these viruses infect young children. Two of the viruses, rubella and parvovirus B19, can be vertically transmitted to fetuses during maternal infection and cause congenital infection. Neurologic complications are common after intrauterine infection with the rubella virus, a condition known as the congenital rubella syndrome. Two, measles and rubella viruses, can induce "slow viral" infections, serious, disorders that can occur several years after the initial exposure to the virus and typically have fatal outcomes.

A close look at EEG in subacute sclerosing panencephalitis

PURPOSE

To define atypical clinical and EEG features of patients with subacute sclerosing panencephalitis that may require an overview of differential diagnosis.

METHODS

A total of 66 EEGs belonging to 53 (17 females and 36 males) consecutive patients with serologically confirmed subacute sclerosing panencephalitis were included in this study. Patient files and EEG data were evaluated retrospectively. EEGs included in the study were sleep-waking EEGs and/or sleep-waking video-EEG records with at least 2 hours duration. Cranial MRIs of the patients taken 2 months before or after the EEG records were included.

RESULTS

Age range at the onset of the disease was 15 to 192 months (mean age: 80.02 months). Epilepsy was diagnosed in 21 (43%) patients. Among epileptic seizures excluding myoclonic jerks, generalized tonic-clonic type constituted the majority (58%). Tonic seizures were documented during the video-EEG recordings in four patients. Epileptogenic activities were found in 56 (83%) EEG recordings. They were localized mainly in frontal (58%), posterior temporal, parietal, occipital (26%), and centrotemporal (8%) regions. Multiple foci were detected in 26 recordings (39%). Epileptiform activities in the 39 (59%) EEGs appeared as unilateral or bilateral diffuse paroxysmal discharges.

CONCLUSIONS

Recognition of uncommon clinical and EEG findings of subacute sclerosing panencephalitis, especially in countries where subacute sclerosing panencephalitis has not been eliminated yet, could be helpful in prevention of misdiagnosis and delay in the management of improvable conditions.

Epidemiology of subacute sclerosing panencephalitis (SSPE) in Germany from 2003 to 2009: a risk estimation

Subacute sclerosing panencephalitis (SSPE) is a fatal long-term complication of measles infection. We performed an estimation of the total number of SSPE cases in Germany for the period 2003 to 2009 and calculated the risk of SSPE after an acute measles infection. SSPE cases were collected from the Surveillance Unit for Rare Paediatric Diseases in Germany and the Institute of Virology and Immunobiology at the University of Würzburg. The total number of SSPE cases was estimated by capture-recapture analysis. For the period 2003 to 2009, 31 children with SSPE who were treated at German hospitals were identified. The capture-recapture estimate was 39 cases (95% confidence interval: 29.2–48.0). The risk of developing SSPE for children contracting measles infection below 5 years of age was calculated as 1∶1700 to 1∶3300. This risk is in the same order of magnitude as the risk of a fatal acute measles infection.

Ocular findings in subacute sclerosing panencephalitis

PURPOSE

The aim of this study was to evaluate the ocular manifestations of subacute sclerosing panencephalitis (SSPE) and to investigate possible risk factors in a relatively large series of patients.

METHODS

In this prospective study, patients who were diagnosed with SSPE and had undergone ophthalmic examination were included.

RESULTS

Of the 59 patients with SSPE, 25 (42.4%) had ocular findings. Ocular involvement was bilateral in 22 (88%) patients. The most characteristic fundus findings in our patients were chorioretinitis. No significant difference was found between the two groups in terms of age, gender, clinical stage, and ocular findings.

CONCLUSIONS

Although ophthalmological findings do not constitute a part of the diagnostic criteria, and the correlation between the clinical stage of SSPE and the ocular findings is unclear, patients with SSPE should be screened and followed up for ocular involvement.

PD1 as a common candidate susceptibility gene of subacute sclerosing panencephalitis

Although the exact pathogenesis of subacute sclerosing panencephalitis (SSPE) remains to be determined, our previous data suggested a genetic contribution to the host susceptibility to SSPE. During chronic viral infection, virus-specific cytotoxic T lymphocytes display poor effector functions. Since co-inhibitory molecules are involved in the suppression of T lymphocytes, we investigated whether single nucleotide polymorphisms (SNPs) of genes encoding co-inhibitory molecules contributed to a susceptibility to SSPE. Association studies on a total of 20 SNPs in 8 genes (CTLA4, CD80, CD86, PD1, PDL1, PDL2, BTLA and HVEM) and subsequent haplotype analysis of 4 SNPs in the PD1 genes were performed in Japanese and Filipino SSPE patients and controls. Then, we investigated a functional difference in promoter activity of two haplotypes and compared the expression levels of PD1 between SSPE and controls. The frequency of GCG(C) haplotype of PD1 containing -606G allele was significantly higher in SSPE patients than in controls both in Japanese and in Filipinos. The promoter activity was significantly higher in the construct with -606G allele than in that with -606A allele. The expression levels of PD1 were significantly higher in SSPE patients than in the controls. Our results suggested that the PD1 gene contributed to a genetic susceptibility to SSPE.

18F-FDG PET and MRS of the early stages of subacute sclerosing panencephalitis in a child with a normal initial MRI

In subacute sclerosing panencephalitis (SSPE), conventional MRI findings have been reported. However, in the early clinical stages, imaging studies can appear normal. Moreover, with no history of infant measles infection, the diagnosis of SSPE can only be arrived at after extensive investigation that must eliminate a number of neurodegenerative diseases. We report here on (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG PET) and magnetic resonance spectroscopy (MRS) findings in a 14-year-old girl with a normal initial MRI who had not contracted measles. Although (18)F-FDG PET and MRS are not specific or diagnostic for SSPE, these techniques can demonstrate substantial metabolic impairments when MRI findings show no obvious abnormalities, as is often the case in the early stages of this disease.

Macular Retinitis as a First Sign of Subacute Sclerosing Panencephalitis: The Importance of Early Diagnosis

PURPOSE

Subacute sclerosing panencephalitis (SSPE) is a subacute inflammatory and neurodegenerative encephalitis related to the measles (rubeola) virus and usually affecting children and young adults. The overwhelming majority of cases follow a progressive downhill course leading to death, although there have been a few case reports of patients who have apparently gone into remission. Ocular changes occur in up to 50% of SSPE cases. Visual complaints, if present, generally antedate the onset of neurological symptoms by a few weeks or months. Here, we report two cases of SSPE presenting with ocular findings and their prognoses.

METHODS

Case reports. In the first case, a 17-year-old male presenting with macular retinitis, the macular findings were mistaken for a heredodegenerative disorder and diagnosis was postponed until neurological findings took place. He died six months after the appearance of his first ophthalmic symptoms despite intravenous immune globulin and isoprinosine therapy. The second case was a 14-year-old male, who presented with only ophthalmological complaints. His diagnosis was based on both ophthalmological findings and high doses of measles IgG in the cerebrospinal fluid (CSF); isoprinosine and intramuscular beta-interferon therapy was started before the onset of neurological findings and in the follow-up time of about 18 months, neurological findings consistent with SSPE did not develop.

RESULTS

The characteristic finding of macular retinitis in SSPE patients is rapid recovery in about one month without therapy. After improvement, neurological findings take place. Once suspected, the diagnosis of SSPE is easily established by the demonstration of high levels of measles antibody in the serum and CSF. Early diagnosis can be made with typical ocular findings and high IgG titers for rubeola in CSF.

CONCLUSION

We suppose that ophthalmic manifestations, especially macular retinitis, may be useful in the diagnosis and management of SSPE cases with elevated IgG titers for rubeola in CSF. The typical clinical findings must be familiar to every ophthalmologist so that diagnostic pitfalls can be prevented and early therapy started. It may be discussed if early diagnosis and therapy will be possible before neurological signs appear, the prognosis of this relentless disease may show a more favorable course.

Subacute sclerosing panencephalitis (SSPE) presenting as acute disseminated encephalomyelitis in a child

Subacute sclerosing panencephalitis (SSPE) typically presents with progressive mental deterioration, behavioral changes, and myoclonic jerks. Atypical presentations are not unknown and may result in diagnostic delays. A 9-year-old girl presented with poor balance and ataxia following an episode of upper respiratory tract infection. Neurological examination revealed mild hemiparesis and ataxia. Brain magnetic resonance imaging revealed scattered areas of T2 and fluid-attenuated inversion recovery hyperintensities in the white matter consistent with acute disseminated encephalomyelitis. Despite treatment with intravenous methylprednisolone, intravenous immunoglobulins, and plasmapheresis, progressive neurological worsening occurred. Later during the course of her illness, subacute sclerosing panencephalitis was suspected from the appearance of burst-suppression pattern on electroencephalogram, and the diagnosis confirmed by elevated titers of measles antibodies in cerebrospinal fluid. Physicians taking care of children need to be aware of atypical presentations of subacute sclerosing panencephalitis and must have a high index of suspicion to prevent diagnostic delays and avoid unnecessary diagnostic and therapeutic interventions.

Impaired cholesterol biosynthesis in a neuronal cell line persistently infected with measles virus

Measles virus remains a substantial cause of morbidity and mortality, producing acute infection with a potential for development of viral persistence. To study the events underlying acute and persistent measles virus infection, we performed a global transcriptional analysis on murine neuroblastoma cells that were acutely or persistently infected with measles virus. In general, we found that acute infection induced significantly more gene expression changes than did persistent infection. A functional enrichment analysis to identify which host pathways were perturbed during each of these infections identified several pathways related to cholesterol biosynthesis, including cholesterol metabolic processes, hydroxymethylglutaryl-coenzyme A (CoA) reductase activity, and acetyl-CoA C-acetyltransferase activity. We also found that measles virus colocalized to lipid rafts in both acute and persistent infection models and that the majority of genes associated with cholesterol synthesis were downregulated in persistent infection relative to acute infection, suggesting a possible link with the defective viral budding in persistent infection. Further, we found that pharmacological inhibition of cholesterol synthesis resulted in the inhibition of viral budding during acute infection. In summary, persistent measles viral infection was associated with decreased cholesterol synthesis, a lower abundance of cholesterol and lipid rafts in the cell membrane, and inhibition of giant-cell formation and release of viral progeny.

Association of toll-like receptor 3 gene polymorphism with subacute sclerosing panencephalitis

Innate immunity plays an important role in measles virus (MV) infection. MV-derived double-stranded RNA is recognized by toll-like receptor 3 (TLR3), retinoic acid-inducible protein I (RIG-I) and melanoma differentiation-associated gene 5 (MDA5). We investigated whether genes encoding these molecules contributed to the development of subacute sclerosing panencephalitis (SSPE) in Japanese individuals. Four single nucleotide polymorphisms (SNPs) of the three genes (TLR3 rs3775291:Leu412Phe, RIG1 rs277729 and rs9695310, and MDA5 rs4664463) were assessed in 40 SSPE patients and 84 controls. Because the TLR3 SNP showed a positive association with SSPE, three additional SNPs were subjected to haplotype analysis. The frequency of 412Phe allele of TLR3 rs3775291 in SSPE patients was significantly higher than that in controls (P=.03). In haplotype analysis of four SNPs in the TLR3 gene, the frequency of -7C/IVS3+71C/Phe412/c.1377C haplotype was significantly increased in SSPE patients (P=.006, odds ration [OR]: 2.2). TLR3 gene may confer host genetic susceptibility to SSPE in Japanese individuals.

Familial subacute sclerosing panencephalitis associated with short latency

The familial recurrence of subacute sclerosing panencephalitis is rare. The study of such cases and a comparison of intrafamilial with sporadic cases of subacute sclerosing panencephalitis may shed light on important pathogenetic factors. We report on the occurrence of subacute sclerosing panencephalitis in two brothers from rural India, who contracted measles infection simultaneously at ages 3 and 11 years. They developed subacute sclerosing panencephalitis 21 and 37 months later, respectively. A diagnosis of subacute sclerosing panencephalitis was based on history, electroencephalographic changes, and significantly raised levels of cerebrospinal-fluid anti-measles virus immunoglobulin G. A comparison of intrafamilial with sporadic cases of subacute sclerosing panencephalitis revealed that latency in familial subacute sclerosing panencephalitis involved a median of 6.4 years (range, 1.0-10.9), significantly (P < 0.05) shorter than in sporadic cases with a median of 9.7 years (range, 2.7-23.4). This difference was because of significantly later infection with measles virus and an earlier onset of encephalitis. We describe the first siblings affected by subacute sclerosing panencephalitis from the Indian subcontinent. We confirmed a more rapid manifestation of subacute sclerosing panencephalitis after measles virus infection in intrafamilial compared with sporadic subacute sclerosing panencephalitis.

Interleukin (IL)-12, IL-2, interferon-gamma gene polymorphisms in subacute sclerosing panencephalitis patients

Mutated measles virus variants have been claimed as the causing agent for subacute sclerosing panencephalitis (SSPE) developing several years after the recovery from measles infection. However, immune dysfunction may be considered related to a genetic susceptibility to this rare disease. Interleukin (IL)-2 -330 (rs2069 762) and +160 (rs2069 763), IL-12 p40 3' UTR (rs3213113), and interferon (IFN)-gamma +874 (rs2430561) polymorphisms are screened by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and PCR-sequence-specific priming (SSP) methods in 87 SSPE patients and 106 healthy controls (HCs) as candidate genes of susceptibility. The distribution of the IL12B genotypes (rs3213113) showed a trend for a significant difference (P = .053). The frequency of IL12B C allele (P = .04, OR: 1.6) and CC genotype (P = .03, OR: 3.2) were both higher in SSPE patients than in HC. The IL2 -330 genotypes revealed lower frequencies of GG genotype (P = .03, OR: 0.4) as well as G allele (P = .02, OR: 0.6) in SSPE. IL2 -330+160 TG haplotype was more frequent in patients (P = .005, OR: 1.8), whereas GG haplotype was less frequent, compared to controls (P = .02, OR: 0.6). IFNG +874 polymorphism revealed no difference. These findings implicate possible effects of genetic polymorphisms in the susceptibility to SSPE, which need to be confirmed in other populations.

Atypical subacute sclerosing panencephalitis: case report

Subacute sclerosing panencephalitis (SSPE) is a progressive inflammatory disorder of the central nervous system with both poor prognosis and high mortality. The disease has been related to a persistent and aberrant measles virus infection and no effective treatment has been available. We report a case of SSPE with atypical features including seizures at onset and a fulminant course in a 8 years-old boy who had been previously immunized against measles.

Subacute sclerosing panencephalitis: is there something different in the younger children?

Subacute sclerosing panencephalitis is a rare, slow viral infection caused by a defective measles virus. Although it is a rare disease, it is still important in developing countries. The onset is generally between the ages of 5-15 years. We reported the clinical and laboratory profile and nature of 9 patients under the age of 4 years with SSPE. Although it is known that a few patients with SSPE have an acute and rapidly fulminating course, in this study rate of progression was rapidly progressive in 6 patients and progressive in 3 of them on admission. Unfortunately, 4 of them were lost to follow up because of address and/or telephone number alterations. Although the number of patients in this study is not sufficient, we suggest that SSPE patients under the age of 4 years have a poor prognosis as a result of progressive or rapidly progressive course despite medical treatment.

Angiotensin-converting enzyme and angiotensin II type 1 receptor gene polymorphisms in children with subacute sclerosing panencephalitis

Subacute sclerosing panencephalitis (SSPE) is a progressive, debilitating, and fatal brain disorder caused by mutant measles virus infection. Although both viral and host factors seem to be involved in SSPE, the exact pathogenesis remains to be determined. Autoimmune demyelination is characteristic of SSPE. The blood angiotensin-converting enzyme (ACE) activity and angiotensin II (Ang II) levels are associated with the ACE gene polymorphism. Proinflammatory effects of Ang II may contribute to the development of SSPE. The aim of this study was to investigate whether the ACE and Ang II type 1 receptor (AT1R) (A1166C) gene polymorphisms were associated with SSPE. The polymorphisms were investigated by polymerase chain reaction (PCR) in 43 patients with SSPE and 100 healthy controls. The genotype distribution of the SSPE children and healthy controls were as follows: DD 58.1% versus 34.0, ID 37.2% versus 48.0%, and II 4.7% versus 18.0, respectively (P = 0.012). Allele frequencies of patients and controls were D 76.7% versus 58.0%, and I 23.3% versus 42.0%, respectively (P = 0.004). The frequency of DD genotype and D allele were significantly higher in SSPE children compared with controls (P < 0.05). AT1R gene polymorphism distribution was found to be similar in SSPE children and control subjects: AA 55.8% versus 60.7%, AC 37.2% versus 32.1%, and CC 7.0% versus 7.2%, respectively (P > 0.05). In conclusion, the results of this study suggest that the DD genotype of ACE I/D polymorphism may be related to SSPE. Due to small size of this study, further studies with more patients are needed to confirm these results.

The role of immune cells and inflammatory cytokines in Paget's disease and multiple myeloma

The osteoclast (OCL) is the primary cell involved in the pathogenesis of Paget's disease (PD) and the destructive bone process in multiple myeloma (MM). Both of these diseases are characterized by increased numbers of OCLs actively resorbing bone, but they differ in that bone formation is greatly increased in PD and is suppressed in MM. The marrow microenvironment plays a critical role in both disease processes, through the increased expression of inflammatory cytokines that enhance osteoclastogenesis and, in the case of MM, also suppress osteoblast (OBL) activity. In addition, the OCLs in PD are intrinsically abnormal, are markedly increased in number and size, and are hyper-responsive to inflammatory cytokines and 1,25-(OH)2D3. This article discusses the role of immune cells and inflammatory cytokines and chemokines in the increased OCL activity in PD and MM bone disease, as well as the potential role of interleukin-3 in the suppression of OBL activity in MM.

Elevated interleukin-12 and CXCL10 in subacute sclerosing panencephalitis

Immunosuppression associated with measles virus (MV) can be demonstrated by cytokine production failure in subacute sclerosing panencephalitis (SSPE) and may have implications on the pathogenesis of the disease. Cytokines (IL-12, IL-10, IL-4, IL-17, IL-18, IFN-alpha, IFN-gamma) and chemokines (CXCL8, CXCL10, CCL2 and CCL5) were measured in the cerebrospinal fluid (CSF) and serum samples from 60 patients with SSPE, 36 patients with infectious and/or inflammatory (IN) and 28 with other non-inflammatory (NIN) neurological diseases by ELISA. IL-12 p70+p40 was elevated in CSF and sera of SSPE when compared to the NIN group. However, the CSF levels of IL-12 p70 alone were not increased, indicating an increase of p40. The CSF of SSPE patients also showed relatively higher levels of IL-10 than that of the NIN group. CXCL10 levels in CSF were significantly higher in SSPE, whereas CXCL8 was increased in sera compared to NIN. No difference was detected in IFN-gamma, IFN-alpha, IL-17, IL-18, IL-4 or CCL2 and CCL5 levels. These results demonstrate that immune response against MV in SSPE may be impaired, although some T cell/Th1 inducing stimulations are present.

Gene expression profiles in peripheral blood mononuclear cells from patients with subacute sclerosing panencephalitis using oligonucleotide microarrays

To investigate the molecular basis for measles virus persistence in patients with subacute sclerosing panencephalitis (SSPE), the authors used a high-density oligonucleotide microarray, and found that the expression of granulysin in peripheral blood mononuclear cells was significantly lower in the patients than in the controls. By a quantitative reverse transcriptase-polymerase chain reaction, the mRNA levels of granulysin were decreased in 30 SSPE patients, and were increased in 7 measles patients, as compared to the 23 controls. These results imply that granulysin might play a role in the host defense against measles virus and possibly be involved in the pathogenesis or pathophysiology of SSPE.

Paget disease of bone

Paget disease of bone (PD) is characterized by excessive bone resorption in focal areas followed by abundant new bone formation, with eventual replacement of the normal bone marrow by vascular and fibrous tissue. The etiology of PD is not well understood, but one PD-linked gene and several other susceptibility loci have been identified, and paramyxoviral gene products have been detected in pagetic osteoclasts. In this review, the pathophysiology of PD and evidence for both a genetic and a viral etiology for PD will be discussed.

Familial subacute sclerosing panencephalitis in two siblings

Subacute sclerosing panencephalitis is a form of chronic persistent measles encephalitis in childhood which rarely manifests after wild virus infection. One previous case of familial subacute sclerosing panencephalitis in two siblings and a number of reports of subacute sclerosing panencephalitis in one member of monozygous twins have been reported in the literature. This report describes a second sibling set who both contracted subacute sclerosing panencephalitis after concurrent sporadic measles infection. Two nonimmunized brothers developed neuropsychological decline and progressive myoclonic and complex partial seizures after earlier measles infection. Stereotyped periodic 5- to 8-second complexes in the electroencephalogram suggested the diagnosis of subacute sclerosing panencephalitis, subsequently confirmed by intrathecal and serum measles-specific immunoglobulin G synthesis and the presence of rubeola nucleocapsid protein and ribonucleic acid in the biopsied brain. The viral genome has not been further subtyped in either patient at this point. Although a rare event, subacute sclerosing panencephalitis cases involving familial and singular monozygous twins may shed light on a variety of host susceptibility factors and specific viral genotype features predisposing to this disease.

Subacute sclerosing panencephalitis: a case with fulminant course after ACTH

We report a 24-month-old male who developed rapidly progressive subacute sclerosing panencephalitis 17 months after measles infection. This patient had a history of measles infection at the age of 7 months and manifested acute encephalitis 1 month later. Developmental delay observed after encephalitis began to improve after a few months. His control electroencephalogram was normal at the age of 14 months. He was admitted to the hospital with flexor spasms and sudden head drops at the age of 24 months. His electroencephalogram revealed slow waves in the posterior regions of the brain. Vigabatrin was begun; his seizures increased with vigabatrin, and adrenocorticotropic hormone was added to the therapy. After five doses of adrenocorticotropic hormone, his clinical findings deteriorated rapidly. His second electroencephalogram revealed periodic discharges synchronized with myoclonias. He was diagnosed as having subacute sclerosing panencephalitis on the basis of clinical and laboratory findings. He lapsed into a vegetative state within a week and died at the age of 25 months. We report this rapidly progressive case to emphasize the importance of recognition of subacute sclerosing panencephalitis before applying steroids in children with myoclonic seizures.

Fulminant subacute sclerosing panencephalitis:two cases with atypical presentation

From 1972 to 2002, we diagnosed and treated 22 cases of subacute sclerosing panencephalitis. We report on two pediatric patients with fulminant subacute sclerosing panencephalitis who had atypical clinical manifestations. In both patients diagnosis was confirmed by elevated titers of CSF and serum antimeasles antibodies. Patient 1 presented with behavioral disorder, dysarthria, and drop attacks, while Patient 2 presented with partial complex seizures. Mental difficulties, personality changes, or myoclonus were not noticed in Patient 2. In both our patients stage I was not prominent, and stage II was of shortened duration. In spite of treatment with isoprinosine and interferon-alpha, both our patients deteriorated rapidly and died 2.5 and 4 months, respectively, after the onset of neurologic symptoms. Both atypical presentation and rapid clinical course observed in our patients could cause problems in making final diagnosis of subacute sclerosing panencephalitis. Therefore, subacute sclerosing panencephalitis should be included in differential diagnosis of acute unexplained encephalopathic diseases.

Treatment of subacute sclerosing panencephalitis with interferon-alpha, ribavirin, and inosiplex

Subacute sclerosing panencephalitis is an almost universally fatal late complication of measles infection for which there is no established treatment. We report a patient with subacute sclerosing panencephalitis who was bed-bound and ataxic and had a left hemiparesis and frequent myoclonus. He was started on a new regimen consisting of intraventricular interferon-alpha (starting at 100,000 U/m2/day, building up to 1 million U/m2/day), ribavirin (60 mg/kg/day intravenously), and inosiplex (3 g/day) and improved markedly. At 10 weeks, the intraventricular reservoir was removed because of bacterial infection, and he was discharged home on oral ribavirin (1200 mg/kg/day) and inosiplex. He continued to improve as judged by neurologic examination, functional independence measurement, neuropsychometry and single photon emission computed tomography (SPECT) imaging. However, after 10 months, he deteriorated suddenly and died before further intraventricular treatment could be instituted. Further trials are needed to evaluate long-term combination therapy in subacute sclerosing panencephalitis.

Subacute sclerosing panencephalitis in an American-born adult

We describe a case of an adult born in the United States who had subacute sclerosing panencephalitis (SSPE). We discuss the possibility that the patient contracted subclinical measles during the 1989-1991 measles epidemic in the United States.

Subacute sclerosing panencephalitis, a measles complication, in an internationally adopted child

A healthy 13-year-old boy who had spent the first 4.5 years of his life in an orphanage in Thailand before adoption by an American couple became ill with subacute sclerosing panencephalitis and died several months later. The boy had most likely contracted wild-type measles in Thailand. Measles complications are a risk in international adoptions.

A 4-year-old with pica, progressive incoordination, and decreased responsiveness

This article reports a typical case of subacute sclerosing panencephalitis (SSPE). The patient contracted measles as an infant during the 1989 to 1991 United States measles epidemic. At 4 1/2 years of age, he developed behavioral changes and quickly progressed through the typical clinical stages of SSPE. His EEG was characteristic. Serum and CSF measles immunoglobulin G were markedly elevated. He remains alive but is vegetative. To our knowledge, this is the first case of SSPE stemming from the 1989 to 1991 measles epidemic. Because infants--the group at highest risk to develop SSPE--were most severely affected by this measles outbreak, other cases of SSPE stemming from this epidemic may occur.

Subacute encephalopathy in a 5-year-old boy

A 5-year-old boy presented with an acute ataxia and altered mental status. Although he initially recovered from these symptoms, he presented a second time with myoclonus and seizures and rapidly became vegetative. Cerebrospinal fluid studies, magnetic resonance imaging, and brain biopsy all confirmed the presence of subacute sclerosing panencephalitis. Despite courses of therapy with cimetidine, amantadine, ribavirin, and inosine, no clinical improvement has been seen. Clinicians need to be alert to the possibility of subacute sclerosing panencephalitis even in the vaccinated child in the appropriate clinical setting.

Characterization of the inflammatory response during acute measles encephalitis in NSE-CD46 transgenic mice

Expression of the human measles virus receptor, CD46, in the murine central nervous system allows infection and replication by wild-type human measles virus (MV) strains (Rall, G.F., Manchester, M., Daniels L.R., Callahan, E., Belman, A., Oldstone, M.B.A., 1997. A transgenic mouse model for measles virus infection of the brain. Proc. Natl. Acad. Sci. U.S.A. 94, 2243-2248). MV replicates in neurons in focal lesions of the cortex, hippocampus and thalamus, leading to death of the animals. In MV-infected CD46 transgenic mice, infiltration of CD4+ and CD8+ T-lymphocytes, B-lymphocytes and macrophages was seen. Upregulation of MHC class I and class II molecules was observed, along with reactive astrocytosis and microgliosis. Increased chemokine mRNAs, especially RANTES and IP-10, and cytokine RNAs IL-6, TNF-alpha, and IL1-beta were observed. Apoptosis of neurons also was increased. No MV replication or inflammation was seen in similarly inoculated nontransgenic littermates. These results further characterize the MV-induced encephalitis in CD46 transgenic mice and highlight similarities to MV infection of the human CNS.

Measles virus spread and pathogenesis in genetically modified mice

Attenuated Edmonston measles virus (MV-Edm) is not pathogenic in standard mice. We show here that MV-Edm inoculated via the natural respiratory route has a limited propagation in the lungs of mice with a targeted mutation inactivating the alpha/beta interferon receptor. A high dose of MV-Edm administered intracerebrally is lethal for about half of these mice. To study the consequences of the availability of a high-affinity receptor for MV propagation, we generated alpha/beta interferon-defective mice expressing human CD46 with human-like tissue specificity. Intranasal infection of these mice with MV-Edm resulted in enhanced spread to the lungs and more prominent inflammatory response. Virus replication was also detected in peripheral blood mononuclear cells, the spleen, and the liver. Moreover, intracerebral inoculation of adult animals with low MV-Edm doses caused encephalitis with almost inevitably lethal outcome. We conclude that in mice alpha/beta interferon controls MV infection and that a high-affinity receptor facilitates, but is not strictly required for, MV spread and pathogenesis.