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Generalized pustular psoriasis (GPP) is a severe type of psoriasis accompanied by systemic and often life-threatening manifestations. The efficacy of the interleukin (IL)-1 antagonist anakinra in cases of GPP underscores the role of IL-1 in disease pathogenesis. We present a case of a middle-aged man who developed an abrupt and severe form of GPP with severe eosinophilia and cholestatic hepatitis. The patient received salvage treatment with a combination of glucocorticoids, hydroxyurea and imatinib, while administration of the IL-1 inhibitor anakinra resulted in remission of hepatitis and a significant skin improvement. However, due to persistent hypersensitivity skin reactions, anakinra was withdrawn and replaced with the anti-IL-1ß antagonist canakinumab. As a result of canakinumab, the patient's skin completely cleared, while no systemic manifestations recurred. After 1 year of continuous canakinumab therapy, the patient remained virtually free of symptoms, while the drug was well tolerated.
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Anticorpos Monoclonais/uso terapêutico , Fármacos Dermatológicos/uso terapêutico , Proteína Antagonista do Receptor de Interleucina 1/uso terapêutico , Interleucina-1beta/antagonistas & inibidores , Psoríase/tratamento farmacológico , Anticorpos Monoclonais Humanizados , Humanos , Masculino , Pessoa de Meia-Idade , Psoríase/induzido quimicamente , Resultado do TratamentoRESUMO
BACKGROUND: Considering that the innate immune system plays a pivotal role in the pathogenesis of chronic obstructive pulmonary disease (COPD), we hypothesized that functional single-nucleotide polymorphisms (SNPs) of innate immune genes affect the disease phenotype and prognosis. AIM: To elucidate the contribution of common functional TLR2 and TLR4 SNPs and genotypic deficiency of the mannose-binding lectin (MBL) protein, both as single parameters and in combination, in Greek COPD patients. RESULTS: In a cohort of 114 Greek COPD patients, we confirmed that the presence of TLR4-D299G or TLR4-T399I SNPs was significantly associated with an earlier COPD stage (p = 0.003 and p = 0.009, respectively). In comparison, the absence of any analyzed polymorphism, including those of TLR2-R753Q and genotypic MBL deficiency, was significantly associated with a more severe disease phenotype, characterized by more frequent exacerbations (p = 0.045). CONCLUSION: Our findings support the notion that the presence of innate immune SNPs, such as functional polymorphisms of TLRs along with MBL deficiency, might exert a protective effect on the COPD phenotype, similar with other immune-mediated disorders.
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Genótipo , Fenótipo , Polimorfismo Genético/genética , Doença Pulmonar Obstrutiva Crônica/genética , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Imunidade Inata/genética , Masculino , Lectina de Ligação a Manose/deficiência , Lectina de Ligação a Manose/genética , Lectina de Ligação a Manose/imunologia , Erros Inatos do Metabolismo/diagnóstico , Erros Inatos do Metabolismo/genética , Erros Inatos do Metabolismo/imunologia , Polimorfismo de Nucleotídeo Único/genética , Prognóstico , Fatores de Proteção , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/imunologia , Fatores de Risco , Fumar/efeitos adversos , Abandono do Hábito de FumarRESUMO
The factors influencing the heterogeneous clinical manifestation of hereditary angioedema due to C1-INH deficiency (C1-INH-HAE) represent one of the oldest unsolved problems of the disease. Considering that factor XII (FXII) levels may affect bradykinin production, we investigated the contribution of the functional promoter polymorphism F12-46C/T in disease phenotype. We studied 258 C1-INH-HAE patients from 113 European families, and we explored possible associations of F12-46C/T with clinical features and the SERPING1 mutational status. Given that our cohort consisted of related subjects, we implemented generalized estimating equations (GEEs), an extension of the generalized linear model accounting for the within-subject correlation. F12-46C/T carriers exhibited a significantly delayed disease onset (P < 0.001) and did not need long-term treatment (P = 0.02). In a GEE linear regression model, the presence of F12-46C/T was significantly associated with a 7-year delay in disease onset (P < 0.0001) regardless of SERPING1 mutational status. It is concluded that F12-46C/T carriage acts as an independent modifier of C1-INH-HAE severity.
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Fator XII/genética , Estudos de Associação Genética , Angioedema Hereditário Tipos I e II/genética , Polimorfismo de Nucleotídeo Único , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Proteínas Inativadoras do Complemento 1/genética , Proteína Inibidora do Complemento C1 , Análise Mutacional de DNA , Feminino , Genótipo , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Mutação , Fenótipo , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Adulto JovemRESUMO
Genes were isolated using the suppression subtractive hybridization method by stimulation of pro/pre B cells with anti-CD40 and interleukin (IL)-4 to mature S mu-Sepsilon-switched cells. One of the strongly upregulated genes encodes a novel murine CC chemokine we have named ABCD-1. The ABCD-1 gene has three exons separated by 1. 2- and 2.7-kb introns. It gives rise to a 2.2-kb transcript containing an open reading frame of 276 nucleotides. Two polyadenylation sites are used, giving rise to cDNAs with either 1550 or 1850 bp of 3' untranslated regions. The open reading frame encodes a 24 amino acid-long leader peptide and a 68 amino acid-long mature protein with a predicted molecular mass of 7.8 kD. ABCD-1 mRNA is found in highest quantities in activated splenic B lymphocytes and dendritic cells. Little chemokine mRNA is present in lung, in unstimulated splenic cells, in thymocytes, and in lymph node cells. No ABCD-1 mRNA is detected in bone marrow, liver, kidney, or brain, in peritoneal exudate cells as well as in the majority of all unstimulated B lineage cells tested. It is also undetectable in Concanavalin A-activated/IL-2-restimulated splenic T cells, and in bone marrow-derived IL-2-induced natural killer cells and IL-3-activated macrophages. Recombinant ABCD-1 revealed a concentration-dependent and specific migration of activated splenic T lymphoblasts in chemotaxis assays. FACS(R) analyses of migrated cells showed no preferential difference in migration of CD4(+) versus CD8(+) T cell blasts. Murine as well as human T cells responded to ABCD-1. Freshly isolated cells from bone marrow, thymus, spleen, and lymph node, IL-2-activated NK cells, and LPS-stimulated splenic cells, all did not show any chemotactic response. Thus, ABCD-1 is the first chemokine produced in large amounts by activated B cells and acting selectively on activated T lymphocytes. Therefore, ABCD-1 is expected to play an important role in the collaboration of dendritic cells and B lymphocytes with T cells in immune responses.
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Linfócitos B/metabolismo , Quimiocinas CC/biossíntese , Células Dendríticas/metabolismo , Linfócitos T/metabolismo , Sequência de Aminoácidos , Animais , Linfócitos B/efeitos dos fármacos , Sequência de Bases , Antígenos CD40/metabolismo , Linhagem Celular , Quimiocina CCL2/biossíntese , Quimiocina CCL22 , Quimiocina CCL4 , Quimiocina CCL5/biossíntese , Quimiocinas CC/química , Quimiocinas CC/genética , Clonagem Molecular , DNA Complementar , Células Dendríticas/efeitos dos fármacos , Humanos , Insetos , Interleucina-4/farmacologia , Ativação Linfocitária , Proteínas Inflamatórias de Macrófagos/biossíntese , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , RNA Mensageiro , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Homologia de Sequência de Aminoácidos , Linfócitos T/efeitos dos fármacosRESUMO
Phenotype of patients with the aprataxin gene mutation varies and according to previous studies, screening of aprataxin gene could be useful, once frataxin gene mutation is excluded in patients with normal GAA expansion in frataxin gene. In the present study, we sought to determine possible causative mutations in aprataxin gene (all exons and flanking intronic sequences) in 14 Greek patients with sporadic cerebellar ataxia all but one without GAA expansion in frataxin gene (1 patient was heterozygous). No detectable point mutation or deletion was found in the aprataxin gene of all the patients. Our results do not confirm the previous studies. This difference may be attributed to the different populations studied and possible different genetic background. It is still questionable whether the screening for aprataxin mutation in Greek patients' Friedreich ataxia phenotype is of clinical importance; larger, multicenter studies are necessary to clarify this issue.
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Proteínas de Ligação a DNA/genética , Proteínas de Ligação ao Ferro/genética , Mutação , Proteínas Nucleares/genética , Degenerações Espinocerebelares/genética , Repetições de Trinucleotídeos , Adolescente , Adulto , Idade de Início , Criança , Pré-Escolar , Estudos de Coortes , Análise Mutacional de DNA , Éxons , Grécia , Humanos , Íntrons , Fenótipo , Expansão das Repetições de Trinucleotídeos , Adulto Jovem , FrataxinaRESUMO
INTRODUCTION: Leptin is an adipocyte-derived cytokine primarily involved in the regulation of body weight and energy balance. In vivo studies suggest that leptin promotes platelet aggregation and thrombosis. Neutrophils are involved in the crosstalk between inflammation and thrombosis in clinical disorders. Leptin is also involved in the regulation of inflammation. AIM: We examined the in vitro effects of leptin on the expression of tissue factor (TF), the primary initiator of coagulation, in healthy neutrophils. MATERIALS AND METHODS/RESULTS: The effects on TF expression were assayed functionally using a modified prothrombin time (mPT), as well as at mRNA and protein levels. The same experiments were performed in parallel with PBMC. Leptin induced functional TF and increased TF mRNA and protein expression in both cell types, as determined by mPT, real-time RT-PCR, western blot, flow cytometry, immunocytochemistry. Inhibition studies revealed that the effect of leptin on TF expression is mediated, at least in part, by JAK2 and PI3K. Our findings, after neutralising TNFalpha in supernatants of leptin-treated cells, also suggest the involvement of TNFalpha in the leptin-induced TF expression in leukocytes. CONCLUSIONS: This study indicates a novel link between inflammation, obesity and thrombosis by showing that leptin is able to trigger the extrinsic coagulation cascade. This work suggests a possible mechanism of the thrombotic effects of hyperleptinemic-associated clinical disorders.
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Janus Quinase 2/metabolismo , Leptina/imunologia , Leucócitos Mononucleares/enzimologia , Neutrófilos/enzimologia , Tromboplastina/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Coagulação Sanguínea/fisiologia , Humanos , Inflamação/fisiopatologia , Leptina/farmacologia , Leucócitos Mononucleares/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Obesidade/imunologia , Obesidade/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Agregação Plaquetária/efeitos dos fármacos , Agregação Plaquetária/fisiologia , Tempo de Protrombina , RNA Mensageiro/metabolismo , Tromboplastina/genética , Trombose/imunologia , Trombose/metabolismoRESUMO
SETTING: In many cases of extra-pulmonary tuberculosis (EPTB), with the exception of paucibacillary analysed specimens, the suspected site of mycobacterial infection is relatively inaccessible or unknown, making laboratory confirmation of TB laborious and problematic. OBJECTIVE: Two different polymerase chain reaction (PCR) based methods were compared to investigate the validity of bone marrow aspiration material as an easily accessible alternative sample for molecular analysis in EPTB. DESIGN: We amplified the same sequence of IS6110 of Mycobacterium tuberculosis complex in 19 confirmed cases of EPTB using two different nested PCR techniques: one in-house 'classic' PCR and another based on LightCycler technology. RESULTS: Both methods demonstrated the same reliability when performed in samples of infected tissue. However, the LightCycler protocol was superior to the in-house system when applied in bone marrow aspiration material, revealing positivity in 18/19 compared to 13/19 samples of 'classic' PCR. CONCLUSION: The application of an optimised LightCycler nested amplification protocol in bone marrow aspirates may promote diagnostic accuracy in difficult and/or urgent cases of EPTB.
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Medula Óssea/química , Mycobacterium tuberculosis/genética , Reação em Cadeia da Polimerase/métodos , Tuberculose/diagnóstico , Adolescente , Adulto , Idoso , Elementos de DNA Transponíveis , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Mutations in the Bruton's tyrosine kinase (BTK ) gene are responsible for X-linked Agammaglobulinemia (XLA), an immunodeficiency caused by a block in B cell differentiation. Non Isotopic RNAse Cleavage Assay (NIRCA), followed by sequencing was used to screen for BTK mutations in 11 Italian XLA patients. Nine novel mutations were identified: 6 missense (Y39S, L512P, L512Q, R544G, S578Y, E589K), one non-sense (Q260X), one frameshift (1599-1602del GCGC) and one in-frame insertion (2037-2038insTTTTAG), that represents the first case of premature stop codon introduction in the BTK coding frame. These data support the high molecular heterogeneity of BTK gene in XLA disease and provide new insight to the diagnosis and to the role of BTK domain in XLA and in B cell signal transduction and development. Hum Mutat 15:117, 2000.
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Agamaglobulinemia/genética , Proteínas Tirosina Quinases/genética , Cromossomo X , Tirosina Quinase da Agamaglobulinemia , Criança , Pré-Escolar , Ligação Genética , Humanos , Lactente , Itália , MutaçãoAssuntos
Transtornos Mieloproliferativos/genética , Polimorfismo de Nucleotídeo Único , Trombose/epidemiologia , Trombose/genética , Receptor 4 Toll-Like/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Células da Medula Óssea/patologia , DNA/genética , DNA/isolamento & purificação , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos Mieloproliferativos/complicações , Fatores de RiscoRESUMO
BACKGROUND: Urate through Nacht Domain, Leucine-Rich Repeat, and pyrin domain-containing protein 3 (NALP3) dependent caspase-1 activation stimulates macrophages to secrete inteleukin-1ß (IL-1ß). Purinergic receptor P2X7 plays a role in the urate induced NALP3 activation. Urate also enhances adaptive immunity indirectly through its effect on antigen presenting cells. In this study, the direct effect of urate on primary human lymphocytes was evaluated. METHODS: Lymphocytes were cultured with or without monosodium urate crystals in the presence or not of a P2X7 inhibitor. Caspase-1 activity was assessed colorimetrically in cell lysates and IL-1ß was measured in supernatants with ELISA. Whole lymphocyte viability and proliferation, as well as T-cell proliferation were assessed by means of 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) assay and of flow cytometry respectively. RESULTS: Urate induced caspase-1 activation and IL-1ß release by lymphocytes. It also induced proliferation of whole lymphocytes and T-cells as well. P2X7 inhibitor abrogated lymphocyte proliferation. CONCLUSIONS: Urate, a well defined danger signal, stimulates directly human lymphocytes in a P2X7 dependent way. The subsequent IL-1ß secretion could enhance inflammation, whereas expansion of lymphocyte clones could facilitate a subsequent adaptive immune response.
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BACKGROUND: Thromboembolic disease (TED) represents one of the main reasons of morbitity and mortality in Western World. Venous and arterial thrombotic disorders have long been viewed as separate pathophysiological entities. However, in recent times the separate nature of arterial and venous thrombotic events has been challenged. Although inherited thrombophilia's predominant clinical manifestation is venous thrombosis, its contribution to arterial thrombosis remains controversial. Purpose of the study was to evaluate the prevalence of the most common thrombophilic mutations, FV Leiden G1691A-FVL and FII G20210A-PTM and to assess the differences between venous, arterial and mixed thrombotic events. Testing for polymorphism MTHFR C677T and antithrombin, protein C and protein S was also performed. Correlations with dyslipidemia, smoking, obesity, homocysteine and antiphospholipid antibodies were made. METHODS: 515 patients with unprovoked TED, 263 males, median age 44 years, were studied. Patients were divided into three groups: 258 with venous thrombosis (group A), 239 with arterial (group B) and 18 with mixed episodes (group C). All patients were interviewed regarding family history of TED, origin, smoking and dyslipidemia. Body mass index (BMI) had been calculated. Molecular assessment of the FVL, PTM and MTHFR C677T was performed. Antithrombin, protein C, protein S, APCR, homocysteine, antiphospholipid antibodies and lipid profile were also measured. RESULTS: The population studied was homogenous among three groups as regards age (p=0.943), lipid profile (p=0.271), BMI (p=0.506), homocysteine (p=0.177), antiphospholipid antibodies (p=0.576), and positive family history (p=0.099). There was no difference in the prevalence of FVL between venous and arterial disease (p=0.440). Significant correlation of PTM with venous TED was found (p=0.001). The number of positive and negative for MTHFR presented statistically significant difference with a support in arterial disease (p=0.05). Moreover, a 2-fold increase in the risk of venous thrombosis in FVL positive patients (odds ratio: 2.153) and a positive correlation of homocysteine levels with MTHFR C677T (p<0.001) was found. CONCLUSIONS: Correlation of PTM with venous thrombosis was established. Analysis showed no difference in prevalence of FVL between venous and arterial thrombosis, indicating that FVL might be a predisposing factor for arterial disease. A significant increase in MTHFR C677T prevalence in arterial disease was found. In conclusion, young patients with unprovoked arterial disease should undergo evaluation for thrombophilic genes. Identification of these mutations is important in the overall assessment and management of patients at high risk. Findings will influence the decisions of stratified approaches for antithrombotic therapy either primary or secondary thromboprophylaxis, the duration of therapy, the potential for avoiding clinical thrombosis by risk factor modification and the genetic counselling of family members. However, further studies are needed to clarify the nature of the association regarding venous and arterial thrombotic events.
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Linfócitos B/metabolismo , Linfócitos B/patologia , Transtornos Linfoproliferativos/genética , Mutação , Fator 88 de Diferenciação Mieloide/genética , Códon , Humanos , Transtornos Linfoproliferativos/diagnóstico , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , PrognósticoRESUMO
OBJECTIVES: To investigate if pepsin is detected, with an activity assay, in the saliva of patients with a clinical diagnosis of laryngopharyngeal reflux (LPR) and can therefore be used as a diagnostic marker of laryngopharyngeal reflux. STUDY DESIGN: Pilot, prospective study. METHODS: Adult participants with a clinical diagnosis of LPR collected whole saliva samples on regular intervals for a day, and upon experiencing symptoms attributed to LPR. Patients were selected on the basis of presence of severe symptoms and laryngoscopic findings of laryngopharyngeal reflux and symptoms of gastroesopharyngeal reflux. They reported voice disorders, dysphagia, throat clearing, excessive secretions, breathing difficulties, cough, globus sensation and throat pain. Control participants reported the absence of pharyngeal and laryngeal symptoms and of symptoms of gastroesophageal reflux. Saliva samples were assayed with fibrinogen on an agarose gel plate. The detection of pepsin was based on the presence of peptic activity which was qualitatively evaluated. RESULTS: The control participants had negative assays. No saliva samples from the LPR patients, collected at regular sampling, tested positive for pepsin. All the samples collected at the presence of symptoms and following regurgitation episodes tested negative for pepsin. Saliva samples pH ranged from 7 to 8. CONCLUSIONS: Pepsin was not detected, with an activity assay, in the saliva of patients with a clinical diagnosis of LPR. A concentration method might be more sensitive although saliva and swallowing physiology renders the detection of pepsin in the saliva difficult.
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Familial Mediterranean fever (FMF) is a disease characterized by recurrent, self-limiting bouts of fever and serositis and caused by altered pyrin due to mutated MEFV gene. FMF is common in the Mediterranean Basin populations, although with varying genetic patterns. The spectrum and clinical significance of MEFV alterations in Greece has yet not been elucidated. The aim of this study was to analyze the spectrum of MEFV alterations in FMF patients and healthy individuals in Greece. A cohort of 152 Greek FMF patients along with 140 Greek healthy controls was enrolled. Non-isotopic RNase cleavage assay (NIRCA) and sequencing allowed mutational and haplotypic analysis of the entire coding sequence of MEFV. The ARLEQUIN 2.0, DNASP 4.0 and PHYLIP software were used for population genetics analysis. Among patients, 127 (83.6%) carried at least one known mutation. The most common mutations identified were M694V (38.1%), M680I (19.7%), V726A (12.2%), E148Q (10.9%) and E230K (6.1%). The total carrier rate among healthy individuals was 0.7%. The presence of R202Q homozygosity in 12 of the remaining 25 MEFV negative FMF patients might be considered as disease related in Greeks. Population genetics analysis revealed that Greeks rely closer to the eastern rather than western populations of the Mediterranean Basin.
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Proteínas do Citoesqueleto/genética , Febre Familiar do Mediterrâneo/diagnóstico , Febre Familiar do Mediterrâneo/genética , Estudos de Coortes , Análise Mutacional de DNA , Febre Familiar do Mediterrâneo/epidemiologia , Genética Populacional , Genótipo , Grécia/epidemiologia , Haplótipos , Humanos , Mutação , Fenótipo , PirinaRESUMO
Several groups have used high doses of interleukin-2 (IL-2), achieving a significant rate of responses in patients with acute myelogenous leukemia (AML). These results have mainly been observed in AML patients with limited disease (bone marrow blasts < 25%), but this therapy is associated with significant toxicity which is dose-related. In this report we describe a patient with AML in whom conventional chemotherapy had achieved partial remission. This patient received subcutaneously intermediate doses of IL-2 (12 x 10(6)/m2/week) and achieved complete remission which was maintained for eleven months. The side effects of IL-2 were mild. The results of this report document the antileukemic effect of IL-2 in AML with limited disease as well as the efficacy of subcutaneous maintenance treatment for prolonged periods.
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Interleucina-2/administração & dosagem , Leucemia Mieloide Aguda/tratamento farmacológico , Humanos , Injeções Subcutâneas , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/administração & dosagemRESUMO
Histiocytic necrotizing lymphadenitis (HNL), or Kikuchi-Fujimoto disease, is a benign, self-limited disease that predominantly occurs in women. The etiology remains undetermined, although a viral or autoimmune hypothesis has been suggested. The disease usually emerges with cervical lymphadenopathy with or without fever. The diagnosis can be confirmed only by histological findings of lymph node biopsy, characterized by necrosis and histiocytic infiltration without neutrophils. We report a case of a 28-year-old woman with a medical history of two episodes of unexplained pulmonary embolisms (3 and 2 years previously) who was admitted to our hospital because of unilateral cervical lymphadenopathy and mild fever that presented 1 week before admission. A diagnosis of HNL was performed by lymph node biopsy. In parallel, whereas the laboratory tests for inherited thrombophilia were negative, a progressive elevated titer of anti-beta(2) glycoprotein I (GPI) antibodies was established. Because of persistent fever, the patient received a short course of corticosteroid therapy and she recovered completely from the HNL after 2 months. It is noteworthy that to date the patient has displayed an elevated titer of anti-beta(2) GPI antibodies (18 months after the recovery from the HNL). Thus, considering the previous history of venous thrombosis and the presence of antiphospholipid antibodies, the diagnosis of primary antiphospholipid syndrome associated with HNL was made. To our knowledge, this is the first report in the literature describing antiphospholipid syndrome associated with HNL. Moreover, a brief literature review is provided with emphasis on the etiology, clinical course, and pathogenesis of this rare disease entity.
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Síndrome Antifosfolipídica/complicações , Linfadenite Histiocítica Necrosante/etiologia , Corticosteroides/uso terapêutico , Adulto , Anticorpos Antifosfolipídeos/sangue , Síndrome Antifosfolipídica/diagnóstico , Feminino , Linfadenite Histiocítica Necrosante/diagnóstico , Linfadenite Histiocítica Necrosante/tratamento farmacológico , Humanos , Embolia Pulmonar/etiologia , Resultado do TratamentoRESUMO
OBJECTIVES: Extrapulmonary tuberculosis (TB) constitutes the main cause of classic fever of unknown origin (FUO) in many populations. The aim of this study was to improve the diagnostic field of the disease using a nested polymerase chain reaction (PCR) assay, specific for the IS6110 insertion element of Mycobacterium tuberculosis complex, in order to achieve a more timely diagnosis and treatment. SETTING: Twenty-four, HIV-negative classic FUO patients who were admitted to the Regional Hospital of Alexandroupolis between April 1997 and July 1999. SUBJECTS AND DESIGN: The above patients were considered as putative extrapulmonary TB after 3 weeks of in-patient investigation and underwent exhaustive examination for diagnosis of the disease. For this purpose, specimens were obtained from peripheral blood and bone marrow from these patients, as well as from damaged tissues, and analysed by both PCR and conventional methods. Anti-tuberculous treatment was initiated in 16 out of 24 patients and the response to this regimen was considered as the final criterion for diagnosis of tuberculosis. RESULTS: Extrapulmonary TB was established in 11 patients. The PCR-based methodology, when applied to samples derived from bone marrow aspirations and suspected damaged tissues, was able to diagnose 10 of them, whereas the conventional methods were able to detect only two. CONCLUSIONS: Our results confirm the diagnostic value of molecular detection of M. tuberculosis in cases of FUO, thus supporting the application of PCR in tissue samples suspected of bacillus infection. Furthermore, our studies demonstrate that bone marrow aspiration specimens constitute an alternative, easy, safe and reliable source for such PCR analysis.