Differences in methylation profiles between long-term survivors and short-term survivors of IDH-wild-type glioblastoma.

Background: Patients with glioblastoma (GBM) have a median overall survival (OS) of approximately 16 months. However, approximately 5% of patients survive >5 years. This study examines the differences in methylation profiles between long-term survivors (>5 years, LTS) and short-term survivors (<1 year, STS) with isocitrate dehydrogenase (IDH)-wild-type GBMs. Methods: In a multicenter retrospective analysis, we identified 25 LTS with a histologically confirmed GBM. They were age- and sex-matched to an STS. The methylation profiles of all 50 samples were analyzed with EPIC 850k, classified according to the DKFZ methylation classifier, and the methylation profiles of LTS versus STS were compared. Results: After methylation profiling, 16/25 LTS and 23/25 STS were confirmed to be IDH-wild-type GBMs, all with +7/-10 signature. LTS had significantly increased O6-methylguanine methyltransferase (MGMT) promoter methylation and higher prevalence of FGFR3-TACC3 fusion (P = .03). STS were more likely to exhibit CDKN2A/B loss (P = .01) and higher frequency of NF1 (P = .02) mutation. There were no significant CpGs identified between LTS versus STS at an adjusted P-value of .05. Unadjusted analyses identified key pathways involved in both LTS and STS. The most common pathways were the Hippo signaling pathway and the Wnt pathway in LTS, and GPCR ligand binding and cell-cell signaling in STS. Conclusions: A small group of patients with IDH-wild-type GBM survive more than 5 years. While there are few differences in the global methylation profiles of LTS compared to STS, our study highlights potential pathways involved in GBMs with a good or poor prognosis.

Review of 20 years of adult medulloblastoma treatment: Chemotherapy prescription trends and survival.

Background: The historic standard of care for adult medulloblastoma has been considered surgery and radiation, while chemotherapy is increasingly being prescribed. This study reviewed 20-year chemotherapy trends at a high-volume center, as well as overall and progression free-survival. Methods: Adults with medulloblastoma treated at an academic center from January 1, 1999 to -December 31, 2020 were reviewed. Patient baseline data were summarized and Kaplan-Meier estimators were used for survival. Results: Forty-nine patients were included; median age was 30 years and male: female ratio was 2:1. Desmoplastic and classical histologies were most common. Of all patients, 23 (47%) were high risk and 7 (14%) metastatic at diagnosis. Only 10 (20%) received initial chemotherapy, of which 70% were high risk and 30% metastatic, with most treated from 2010 to 2020. Forty percent of initial chemotherapy patients received salvage chemotherapy for recurrence or metastases (of all patients, 49% required salvage). Initial chemotherapy regimens were mainly cisplatin/lomustine/vincristine, and at recurrence cisplatin/etoposide. Median overall survival was 8.6 years (95% CI 7.5-∞), with 1-, 5-, and 10-year survival at 95.8%, 72%, and 46.7%. Median overall survival for those who did not receive initial chemotherapy was 12.4 years and 7.4 years for those who did (P-value .2). Conclusions: Twenty years of adult medulloblastoma treatment was reviewed. Initial chemotherapy patients, most of whom were high risk, trended towards worse survival, but this was nonsignificant. The ideal timing and choice of chemotherapy for adult medulloblastoma is unknown-challenges of administering chemotherapy following photon craniospinal irradiation may have prevented it from becoming routine.

Neurocognitive impairment, neurobehavioral symptoms, fatigue, sleep disturbance, and depressive symptoms in patients with newly diagnosed glioblastoma.

Background: In addition to poor survival rates, individuals with glioblastoma (GBM) are at risk of neurocognitive impairment due to multiple factors. This study aimed to characterize neurocognitive impairment, neurobehavioral symptoms, fatigue, sleep disturbance, and depressive symptoms in newly diagnosed GBM patients; and to examine whether neurobehavioral symptoms, fatigue, sleep, and depressive symptoms influence neurocognitive performance. Methods: This study was part of a prospective, inception cohort, single-arm exercise intervention in which GBM patients underwent a neuropsychological assessment shortly after diagnosis (median 4 weeks; ie, baseline) and 3, 6, 12, and 18 months later, or until tumor progression. Here, we present baseline data. Forty-five GBM patients (mean age = 55 years) completed objective neurocognitive tests, and self-report measures of neurobehavioral symptoms, fatigue, sleep disturbance, and depressive symptoms. Results: Compared to normative samples, GBM patients scored significantly lower on all neurocognitive tests, with 34 (76%) patients exhibiting neurocognitive impairment. Specifically, 53% exhibited impairment in memory retention, 51% in executive function, 42% in immediate recall, 41% in verbal fluency, and 24% in attention. There were high rates of clinically elevated sleep disturbance (70%), fatigue (57%), depressive symptoms (16%), and neurobehavioral symptoms (27%). A multivariate regression analysis revealed that depressive symptoms are significantly associated with neurocognitive impairment. Conclusions: GBM patients are vulnerable to adverse outcomes including neurocognitive impairment, neurobehavioral symptoms, fatigue, sleep disturbance, and depressive symptoms shortly after diagnosis, prior to completing chemoradiation. Those with increased depressive symptoms are more likely to demonstrate neurocognitive impairment, highlighting the need for early identification and treatment of depression in this population.

Bevacizumab for Cerebral Radionecrosis: A Single-Center Experience.

BACKGROUND: Cerebral radionecrosis, a subacute or late effect of radiotherapy, can be debilitating and difficult to treat. Steroids can reduce symptoms, but have significant long-term side effects. Bevacizumab has been shown to reduce edema and other radiologic features associated with radionecrosis and improve patient symptoms. We report our experience using bevacizumab for cerebral radionecrosis. METHODS: We retrospectively reviewed the charts of all patients treated at our institution with bevacizumab for non-glioma-associated cerebral radionecrosis. We recorded change in symptoms, change in steroids, change in performance status, time to tumor progression, and time to death. We delineated the volume of necrosis pre- and post-bevacizumab on T1-post-gadolinium and fluid-attenuated inversion recovery (FLAIR) MRI scans. RESULTS: We identified 15 patients, 8 with brain metastases, 6 with meningioma, and 1 with nasopharyngeal carcinoma. Most received four doses of bevacizumab, 7.5 mg/kg q 3 weeks × 4 doses. Neuroimaging demonstrated a reduced T1 gadolinium-enhancing volume and edema in 14/15 patients (the average reduction in T1-post-gadolinium volume was 3.0 cm3, and average reduction in FLAIR volume was 27.9 cm3). There was no appreciable change in patient performance status. Steroid doses decreased in five of nine patients. There was a high rate (26%) of adverse events, including pulmonary embolism, stroke, and wound dehiscence. The median progression-free survival was 6.5 months. CONCLUSION: Although bevacizumab is commonly prescribed for cerebral radionecrosis, in our retrospective cohort, the clinical benefits were modest and there was significant toxicity.

Tratamiento ortodóncico-quirúrgico de pacientes con asimetría facial / Orthodontic-surgical treatment of patients with facial asymmetry

Introducción: la asimetría facial es una condición notoria en el tercio inferior de la facie del sujeto y entre los tercios medio y superior, en este último será menos evidente esta condición, de tal manera que podría considerarse como una de las molestias de mayor incidencia en pacientes con necesidades o no de terapia or- todóncica. Objetivo: evaluar mediante una revisión de la literatura los tratamientos ortodóncico-quirúrgicos de pacientes con asimetría facial. Material y métodos: la literatura se seleccionó mediante una búsqueda en las bases de datos electrónicas: PubMed, Scopus, Web of Science. Las palabras clave utilizadas fueron: facial asymmetry, asymmetry, surgical treatment, surgical orthodontic treatment. La búsqueda se restringió a artículos en inglés publicados del año 2011 al 2021. Resultados: después de aplicar los criterios de inclusión y exclusión en total se obtuvieron y revisaron 27 artículos. Se realizó la revisión de literatura del tratamiento ortodóncico-quirúrgico en pacientes con asimetría facial. Conclusión: es preciso el abordaje ortodóntico quirúrgico para la corrección de la asimetría facial, del protocolo dependerá la situación clínica y la elección de tratamiento ortodóntico quirúrgico, lo que brindará mejoras significativas en la simetría facial (AU)

Introduction: facial asymmetry, is a notorious condition in the lower third of the subject's facie and between the middle and upper thirds, in the latter this condition will be less evident; in such a way, it could be considered as one of the discomforts of greater incidence in patients with needs or not of orthodontic therapy. Objective: to evaluate by means of a literature review the orthodontic-surgical treatment of patients with facial asymmetry. Material and methods: the literature was selected through a search in the following electronic databases: PubMed, Scopus, Web of Science. The keywords used were: facial asymmetry, asymmetry, surgical treatment, surgical orthodontic treatment. The search was restricted to articles in English published from 2011 to 2021. Results: after applying the inclusion and exclusion criteria, a total of 27 articles were obtained and reviewed. The literature review of orthodontic-surgical treatment in patients with facial asymmetry was performed. Conclusion: surgical orthodontic approach is necessary for the correction of facial asymmetry, the protocol will depend on the clinical situation, the choice of surgical orthodontic treatment, which will give significant improvements in facial symmetry (AU)

Opinion & Special Article: Glioma Classification: How to Interpret Molecular Markers in a Diffuse Glioma Pathology Report.

Diffuse infiltrating gliomas are the most common malignant brain tumors in adults. The 2021 World Health Organization classification for central nervous system tumors (CNS5 WHO) has significantly altered the rules for classification and grading of diffuse gliomas. Clinicians, including neurology residents and neurologists, will have to consider the changes that include the introduction of new tumor types, allotting established tumor types to other groups, and substituting previously essential morphological features for additional molecular markers. For example, in the current classification, glioblastoma is defined as isocitrate dehydrogenase (IDH)-wildtype, grade 4. Whereas, a grade 4 IDH-mutated astrocytic glioma is referred to as astrocytoma, IDH-mutated, grade 4. Additionally, potential targeted treatments, based on the underlying molecular alterations, have become therapeutic options for diffuse gliomas. For clinicians, it is important to know the rationale for why these options are only available for specific tumors. Due to the emphasis of molecular markers in the CNS5 WHO classification, interpretation of a pathology report and understanding of its clinical implications can be challenging. This review describes the most important molecular alterations in glioma, summarizes the recent changes in the CNS5 WHO classification for glioma, and presents a stepwise approach for trainees and neurologist to decipher a glioma pathology report.

Geriatric Pharmacology Case Series: Direct Oral Anticoagulants for Older People With Cancer.

This case study focuses on the treatment of a patient with cancer-associated venous thromboembolism (VTE). This is a common complication of cancer that can result in substantial morbidity and mortality. The case reviews the approach of analyzing older people with cancer-associated VTE and its treatment options.

Plasma rico en plaquetas autólogo tópico para el tratamiento de la úlcera de pie diabético / Autologous platelet rich plasma for the treatment of diabetic foot ulcer

Background: Diabetic foot ulcer is one of the frequent complications of diabetes. 15% to 25% develop ulcers at some point in their lives. The existing evidence on the efficacy of topical autologous platelet-rich plasma (PRP) for the treatment of diabetic foot ulcers was assessed. Method: A search for randomized controlled clinical trials comparing autologous topical PRP vs standard care and placebo was carried out in Pubmed, Cochrane, Lilacs, and Clinical Trials databases. For dichotomous outcomes, relative risk analysis, 95% CI, and the Mantel-Haenszel method were used; for continuous outcomes, the mean difference and inverse variance method were calculated. Results: The result of the search was 153 studies, 28 duplicates were excluded, 59 by title and abstract, and 52 by reading the article. 14 studies were included in the review, 8 for qualitative review and 6 for quantitative. Six studies with a complete ulcer-healing outcome at the end of the intervention were evaluated, out of a total of 415 participants (relative risk 1.24 CI [1.11, 1.40]). The outcome epithelialized area at the end of the intervention, measured in cm², was not reported. A single study measured quality of life and pain. Conclusion: There is evidence of the beneficial effect of topical autologous PRP for the healing of diabetic foot ulcers, however, studies of higher methodological quality, greater production of clinical trials in Latin America, and assessment of the quality of life and pain are needed.

Antecedentes: La úlcera de pie diabético constituye una de las complicaciones frecuentes de la diabetes. Del 15% al 25% de los pacientes presentan úlceras en algún momento de su vida. Se valoró la evidencia existente sobre la eficacia del plasma rico en plaquetas (PRP) autólogo tópico para el tratamiento de úlcera de pie diabético. Método: Se llevó a cabo a partir de datos de Pubmed, Cochrane, Lilacs y Clinical Trials, búsqueda de ensayos clínicos aleatorizados controlados que compararon PRP autólogo tópico frente a cuidados estándar y placebo. Para los resultados dicotómicos se usó el análisis de riesgo relativo, con intervalos de confianza del 95% y el método de Mantel-Haenszel; para los resultados continuos, se calculó la diferencia de medias y método de varianza inversa. Resultados: El resultado de la búsqueda fue 153 estudios, se excluyeron 28 duplicados, 59 por título y abstract y 52 por lectura de artículo. Se incluyeron 14 trabajos en la revisión, 8 para revisión cualitativa y 6 para cuantitativa. Se valoraron 6 estudios con desenlace de curación completa de úlcera al final de la intervención, sobre un total de 415 participantes (riesgo relativo 1.24 [IC 95%: 1.11 a 1.40]). No se informó el desenlace área epitelizada al final de la intervención medida en cm². Un solo estudio midió calidad de vida y dolor. Conclusión: Existe evidencia del efecto beneficioso del PRP autólogo tópico para la curación de úlcera de pie diabético; no obstante, se necesitan estudios de mayor calidad metodológica, mayor producción de ensayos clínicos en Latinoamérica y valoración de calidad de vida y dolor.

Esquemas terapéuticos y factores asociados a mortalidad en pacientes con cuadro severo de COVID-19 atendidos en Hospital Nacional Alberto Sabogal Sologuren 2020 / Therapeutic regimens and factors associated with mortality in patients with severe COVID-19 infection treated at the Hospital Nacional Alberto Sabogal Sologuren, 2020

RESUMEN Objetivo: Explorar el esquema terapéutico y factores asociados a mortalidad en pacientes con un cuadro severo de COVID-19 atendidos en el Hospital Nacional Alberto Sabogal Sologuren en 2020. Materiales y métodos: Estudio observacional, analítico de caso-control y prospectivo. Fueron incluidos los pacientes que ingresaron al hospital con un cuadro severo de COVID-19 entre junio a septiembre de 2020 y fueron clasificados en dos grupos: el grupo caso (61 pacientes fallecidos) y el grupo control (60 sobrevivientes que recibieron el alta hospitalaria). Los datos fueron analizados en el software estadístico Stata(R) y se realizó análisis bivariado y multivariado con regresión logística, nivel de confianza del 95 %. Resultados: En pacientes con cuadro severo de COVID-19, la edad mayor de 60 años está asociada a la mortalidad (p=0,035; OR=2,21 IC: [1,05-4,63]). Los esquemas terapéuticos fueron variados, los participantes que recibieron metilprednisolona a dosis altas tuvieron mayor probabilidad de morir en comparación a los que recibieron otros corticoides (p=0,001; OR ajustado=5,18 IC: [1,94-13,83]). El tratamiento con azitromicina por más de cinco días incrementa la probabilidad de fallecer en comparación a los que la tomaron por menos días (p=0,000; OR ajustado=7,14 IC: [2,22-22,99]). El modelo multivariado tenía una probabilidad predictiva de mortalidad de 73,06 % para los pacientes con cuadro severo de COVID-19. Conclusiones: Los esquemas terapéuticos que incluyen administración de metilprednisolona a dosis altas y azitromicina por más de 5 días incrementan la probabilidad de fallecer en los pacientes con una presentación severa de COVID-19. Además, la edad mayor a 60 años estuvo asociada a la mortalidad en los pacientes analizados en el estudio.

ABSTRACT Objective: To explore the therapeutic regimen and factors associated with mortality in patients with severe COVID-19 infection treated at the Hospital Nacional Alberto Sabogal Sologuren in 2020. Materials and methods: An observational, case-control, analytical and prospective study conducted in patients with severe COVID-19 infection at hospital admission between June and September 2020. The study population was classified into two groups: case group (61 deceased patients) and control group (60 discharged patients). Data were analyzed using Stata statistical software. Bivariate and multivariate logistic regression analyses were performed with a 95 % confidence level. Results: As for patients with severe COVID-19 infection, ages older than 60 years are associated with mortality (p = 0.035; OR = 2.21; CI: [1.05 - 4.63]). Different therapeutic regimens were included in the research: patients who received high-dose methylprednisolone had more probability of dying compared to those who received other corticosteroids (p = 0.001; adjusted OR = 5.18; CI: [1.94 - 13.83]). Patients who were treated with azithromycin for more than five days had more probability of dying compared to those that took it for fewer days (p = 0.000; adjusted OR = 7.14; CI: [2.22 - 22.99]). The multivariate model showed a 73.06 % predictive probability of mortality for patients with severe COVID-19 infection. Conclusions: The therapeutic regimens that include the administration of high-dose methylprednisolone and azithromycin for more than five days increase the probability of dying in patients with severe COVID-19 infection. Furthermore, ages over 60 years were associated with mortality in the patients who participated in the study.

Outcomes of presumed malignant glioma treated without pathological confirmation: a retrospective, single-center analysis.

BACKGROUND: Tissue diagnosis is essential in the usual management of high-grade glioma. In rare circumstances, due to patient preference, performance status, comorbidities, or tumor location, biopsy is not feasible. Sometimes a biopsy is nondiagnostic. Many neuro-oncology clinics have patients like this, but these patients' outcomes and responses to treatment are not known. METHODS: We retrospectively reviewed records from adult patients diagnosed with presumed high-grade glioma of the brain without definitive pathology, diagnosed between 2004 and 2016. We recorded several clinical variables including date of first diagnostic imaging and date of death. RESULTS: We identified 61 patients and subclassified them to brainstem glioma (n = 32), supratentorial presumed glioblastoma (n = 24), presumed thalamic diffuse midline glioma (n = 2), gliomatosis cerebri (n = 2), and cerebellar glioma (n = 1). Most brainstem glioma patients had no biopsy because of tumor location. Supratentorial presumed glioblastoma patients had no biopsy predominantly because of comorbidities. Median survival, from first diagnostic imaging, was 3.2 months (95% CI: 2.9 to 6.3 months) in the supratentorial glioblastoma group and 18.5 months (95% CI: 13.0 to 44.1 months) in the brainstem group. Treatment with radiation or chemotherapy did not alter the median survival of the supratentorial glioblastoma group (hazard ratio 1.41, uncorrected P = .5). CONCLUSIONS: Patients with imaging diagnoses of high-grade glioma have similar, if not worse, survival than those with pathological confirmation. Based on these uncontrolled data, it is unclear how effective radiation or chemotherapy is in this population.

Chimeric cells of maternal origin do not appear to be pathogenic in the juvenile idiopathic inflammatory myopathies or muscular dystrophy.

INTRODUCTION: Microchimeric cells have been studied for over a decade, with conflicting reports on their presence and role in autoimmune and other inflammatory diseases. To determine whether microchimeric cells were pathogenic or mediating tissue repair in inflammatory myopathies, we phenotyped and quantified microchimeric cells in juvenile idiopathic inflammatory myopathies (JIIM), muscular dystrophy (MD), and noninflammatory control muscle tissues. METHOD: Fluorescence immunophenotyping for infiltrating cells with sequential fluorescence in situ hybridization was performed on muscle biopsies from ten patients with JIIM, nine with MD and ten controls. RESULTS: Microchimeric cells were significantly increased in MD muscle (0.079 ± 0.024 microchimeric cells/mm(2) tissue) compared to controls (0.019 ± 0.007 cells/mm(2) tissue, p = 0.01), but not elevated in JIIM muscle (0.043 ± 0.015 cells/mm(2)). Significantly more CD4+ and CD8+ microchimeric cells were in the muscle of patients with MD compared with controls (mean 0.053 ± 0.020/mm(2) versus 0 ± 0/mm(2) p = 0.003 and 0.043 ± 0.023/mm(2) versus 0 ± 0/mm(2) p = 0.025, respectively). No differences in microchimeric cells between JIIM, MD, and noninflammatory controls were found for CD3+, Class II+, CD25+, CD45RA+, and CD123+ phenotypes, and no microchimeric cells were detected in CD20, CD83, or CD45RO populations. The locations of microchimeric cells were similar in all three conditions, with MD muscle having more microchimeric cells in perimysial regions than controls, and JIIM having fewer microchimeric muscle nuclei than MD. Microchimeric inflammatory cells were found, in most cases, at significantly lower proportions than autologous cells of the same phenotype. CONCLUSIONS: Microchimeric cells are not specific to autoimmune disease, and may not be important in muscle inflammation or tissue repair in JIIM.

Epizootiology of Tacaribe serocomplex viruses (Arenaviridae) associated with neotomine rodents (Cricetidae, Neotominae) in southern California.

The objective of this study was to advance our knowledge of the epizootiology of Bear Canyon virus and other Tacaribe serocomplex viruses (Arenaviridae) associated with wild rodents in California. Antibody (immunoglobulin G [IgG]) to a Tacaribe serocomplex virus was found in 145 (3.6%) of 3977 neotomine rodents (Cricetidae: Neotominae) captured in six counties in southern California. The majority (122 or 84.1%) of the 145 antibody-positive rodents were big-eared woodrats (Neotoma macrotis) or California mice (Peromyscus californicus). The 23 other antibody-positive rodents included a white-throated woodrat (N. albigula), desert woodrat (N. lepida), Bryant's woodrats (N. bryanti), brush mice (P. boylii), cactus mice (P. eremicus), and deer mice (P. maniculatus). Analyses of viral nucleocapsid protein gene sequence data indicated that Bear Canyon virus is associated with N. macrotis and/or P. californicus in Santa Barbara County, Los Angeles County, Orange County, and western Riverside County. Together, analyses of field data and antibody prevalence data indicated that N. macrotis is the principal host of Bear Canyon virus. Last, the analyses of viral nucleocapsid protein gene sequence data suggested that the Tacaribe serocomplex virus associated with N. albigula and N. lepida in eastern Riverside County represents a novel species (tentatively named "Palo Verde virus") in the genus Arenavirus.

SIG, Teledetección y modelo basado en variables oceanográficas aplicados a la pesqueria de la Pota (Dosidicus gigas) en Pita, 2010 - 2011 / GIS, Remote Sensing and prototype based in oceanographic variables applied to the fishery of the Humbold squid ( Dosidicus gigas) in Paita, 2010 - 201

En este trabajo se presenta el resultado de la aplicación de los Sistemas de Información Geográfica (SIG), en el análisis de las variables oceanográficas temperatura y clorofila a, sobre la ubicación de las zonas de pesca. Se utiliza el SOFTWARE ARC GIS 9,2, en el se ha superpuesto las capas de temperatura clorofila a y capturas por parte de las embarcaciones artesanales que se dedican a la pesca de pota. Los resultados obtenidos nos demuestran que hay una correlación entre la ubicación de las zonas de pesca y la distribución de la temperatura superficial del mar y además con la concentración de clorofila a. Se determino el rango de ubicación de temperatura entre 16 y 23°C, siendo la temperatura optima en función a las descargas entre 18 y 20°C. La clorofila a por su parte osciló para la mayores descargas entre 1 y 2 mg/m3, pero el rango en el que se le pesco fue entre 0,5 y 2 mg/m3. Podemos decir que es posible realizar el seguimiento de algunas pesqeurías a través de la combinación de algunos parámetros oceanográficos y el manejo de software de Sistemas de Información Geográfica.

In this work presents the results of the application of Geographic Information systems (GIS) in the analysis of oceanographic variables: temperature and chlorophyll A, on the location of the fishing areas. It is used SOFTWARE ARC GIS 9.2, on which it has been put on top the layers of chlorophyll A and temperature catch by the artisanal vessels engaged in fishing for Humboldt squid. The final results show us that there is a correlation between the location of the fishing areas and the distribution of sea surface temperature and also with the concentration of chlorophyll A. It was determined the location of temperature range between 16° and 23°C, being the optimum temperature according to discharges between 18° and 20° C. Meanwhile, ChlorophyllA varies for greater shock ranged from 1 to 2 mg/m3 but the range in which it was fished it was between 0.5 and 2 mg/ m3. We can say that it is possible to monitor some deep-sea fisheries through the combination of some oceanographic parameters and software management of Geopraphic Information System.

Increased microchimeric CD4+ T lymphocytes in peripheral blood from women with systemic sclerosis.

Recent studies have demonstrated the presence of microchimeric cells in peripheral blood and skin lesions from patients with systemic sclerosis (SSc). In a previous study we found that some peripheral blood CD3+ cells from female patients with SSc contained male DNA. Here, peripheral blood samples from 47 patients with SSc (30 with diffuse cutaneous SSc and 17 with limited cutaneous SSc) and 22 healthy controls were sorted for CD4+ and CD8+ T cells. Both positively and negatively selected populations were analyzed for male DNA by quantitative PCR. Analysis of Y chromosome sequences in the sorted cells demonstrated the presence of microchimerism in 82.9% of SSc patients compared to 63.6% of controls. The numbers of CD4+ and CD8+ T cells were found to be significantly higher in the SSc patients than in controls. Furthermore, patients with dcSSc were observed to have significantly more CD4+ microchimeric T cells than the controls. In the CD8+ T-cell population, there was a trend toward more microchimeric cells in the patients but this did not reach significance. These results support the hypothesis that microchimeric CD4+ T cells may be involved in the pathogenesis of SSc.