Hereditary autoinflammatory syndromes: a Brazilian multicenter study.

OBJECTIVE: To evaluate the prevalence of genetic defects in clinically suspected autoinflammatory syndromes (AIS) in a Brazilian multicenter study. METHODS: The study included 102 patients with a clinical diagnosis of Cryopyrin Associated Periodic Syndromes (CAPS), TNF Receptor Associated Periodic Syndrome (TRAPS), Familial Mediterranean Fever (FMF), Mevalonate Kinase Deficiency (MKD) and Pediatric Granulomatous Arthritis (PGA). One of the five AIS-related genes (NLRP3, TNFRSF1A, MEFV, MVK and NOD2) was evaluated in each patient by direct DNA sequencing, based on the most probable clinical suspect. RESULTS: Clinical diagnoses of the 102 patients were: CAPS (n = 28), TRAPS (n = 31), FMF (n = 17), MKD (n = 17) and PGA (n = 9). Of them, 27/102 (26 %) had a confirmed genetic diagnosis: 6/28 (21 %) CAPS patients, 7/31 (23 %) TRAPS, 3/17 (18 %) FMF, 3/17 (18 %) MKD and 8/9 (89 %) PGA. CONCLUSION: We have found that approximately one third of the Brazilian patients with a clinical suspicion of AIS have a confirmed genetic diagnosis.

Pediatric hereditary autoinflammatory syndromes.

OBJECTIVE: To describe the most prevalent pediatric hereditary autoinflammatory syndromes. SOURCES: A review of the literature including relevant references from the PubMed and SciELO was carried out using the keywords autoinflammatory syndromes and child. SUMMARY OF THE FINDINGS: The hereditary autoinflammatory syndromes are caused by monogenic defects of innate immunity and are classified as primary immunodeficiencies. These syndromes are characterized by recurrent or persistent systemic inflammatory symptoms and must be distinguished from infectious diseases, autoimmune diseases, and other primary immunodeficiencies. This review describes the epidemiological, clinical and laboratory features, prognosis, and treatment of the main autoinflammatory syndromes, namely: familial Mediterranean fever; TNF receptor associated periodic syndrome; the cryopyrinopathies; mevalonate kinase deficiency; pediatric granulomatous arthritis; pyogenic arthritis, pyoderma gangrenosum and acne syndrome; Majeed syndrome; and deficiency of interleukin 1 receptor antagonist. The cryopyrinopathies discussed include neonatal-onset multisystem inflammatory disease (also known as chronic infantile neurologic, cutaneous and articular syndrome), Muckle-Wells syndrome, and familial cold autoinflammatory syndrome. CONCLUSIONS: Pediatricians must recognize the clinical features of the most prevalent autoinflammatory syndromes. Early referral to a pediatric rheumatologist may allow early diagnosis and institution of treatment, with improvement in the quality of life of these patients.

Síndromes autoinflamatórias hereditárias na faixa etária pediátrica / Pediatric hereditary autoinflammatory syndromes

OBJETIVO: Descrever as principais síndromes autoinflamatórias hereditárias na faixa etária pediátrica. FONTES DOS DADOS: Foi realizada uma revisão da literatura nas bases de dados PubMed e SciELO, utilizando as palavras-chave "síndromes autoinflamatórias” e "criança”, e incluindo referências bibliográficas relevantes. SÍNTESE DOS DADOS: As principais síndromes autoinflamatórias são causadas por defeitos monogênicos em proteínas da imunidade inata, sendo consideradas imunodeficiências primárias. Elas são caracterizadas clinicamente por sintomas inflamatórios sistêmicos recorrentes ou contínuos e devem ser diferenciadas das doenças infecciosas, autoimunes e outras imunodeficiências primárias. Nesta revisão, foram enfatizadas características epidemiológicas, manifestações clínicas, alterações laboratoriais, prognóstico e terapia das principais síndromes autoinflamatórias: febre familiar do Mediterrâneo; síndrome periódica associada ao receptor de fator de necrose tumoral; criopirinopatias; deficiência de mevalonato-quinase; artrite granulomatosa pediátrica; síndrome de pioderma gangrenoso, artrite piogênica e acne; síndrome de Majeed; e deficiência do antagonista do receptor de interleucina-1. As criopirinopatias discutidas foram: doença inflamatória multissistêmica de início neonatal ou síndrome neurológica, cutânea e articular crônica infantil, síndrome de Muckle-Wells e síndrome autoinflamatória familiar associada ao frio. CONCLUSÕES: É importante que o pediatra reconheça as síndromes autoinflamatórias hereditárias mais prevalentes, pois o encaminhamento ao reumatologista pediátrico pode permitir um diagnóstico precoce e uma instituição de tratamento adequado, possibilitando uma melhora da qualidade de vida dos pacientes.

OBJECTIVE: To describe the most prevalent pediatric hereditary autoinflammatory syndromes. SOURCES: A review of the literature including relevant references from the PubMed and SciELO was carried out using the keywords autoinflammatory syndromes and child. SUMMARY OF THE FINDINGS: The hereditary autoinflammatory syndromes are caused by monogenic defects of innate immunity and are classified as primary immunodeficiencies. These syndromes are characterized by recurrent or persistent systemic inflammatory symptoms and must be distinguished from infectious diseases, autoimmune diseases, and other primary immunodeficiencies. This review describes the epidemiological, clinical and laboratory features, prognosis, and treatment of the main autoinflammatory syndromes, namely: familial Mediterranean fever; TNF receptor associated periodic syndrome; the cryopyrinopathies; mevalonate kinase deficiency; pediatric granulomatous arthritis; pyogenic arthritis, pyoderma gangrenosum and acne syndrome; Majeed syndrome; and deficiency of interleukin 1 receptor antagonist. The cryopyrinopathies discussed include neonatal-onset multisystem inflammatory disease (also known as chronic infantile neurologic, cutaneous and articular syndrome) Muckle-Wells syndrome, and familial cold autoinflammatory syndrome. CONCLUSIONS: Pediatricians must recognize the clinical features of the most prevalent autoinflammatory syndromes. Early referral to a pediatric rheumatologist may allow early diagnosis and institution of treatment, with improvement in the quality of life of these patients.

TNF receptor-associated periodic syndrome (TRAPS): description of a novel TNFRSF1A mutation and response to etanercept.

TRAPS is the most common of the autosomal dominant periodic fever syndromes. It is caused by mutations in the TNFRSF1A gene, which encodes for the type 1 TNF-receptor (TNFR1). We describe here a Brazilian patient with TRAPS associated to a novel TNFRSF1A de novo mutation and the response to anti-TNF therapy. The patient is a 9-year-old girl with recurrent fevers since the age of 3 years, usually lasting 3 to 7 days, and recurring every other week. These episodes are associated with mild abdominal pain, nausea, vomiting and generalized myalgia. Recurrent conjunctivitis and erysipela-like skin lesions in the lower limbs also occur. Laboratory studies show persistent normocytic normochromic anemia, thrombocytosis, elevated erythrocyte sedimentation rate and C-reactive protein. IgD levels are normal. Mutational screening of TNFRSF1A revealed the association of a novel C30F mutation with the common R92Q low-penetrance mutation. The R92Q mutation is seen in 5% of the general population and is associated with an atypical inflammatory phenotype. The patient had a very good response to etanercept, with cessation of fever and normalization of inflammatory markers. Our report expands the spectrum of TNFRSF1A mutations associated with TRAPS, adding further evidence for possible additive effects of a low-penetration R92Q and cysteine residue mutations, and confirms etanercept as an efficacious treatment alternative.

Phenotype-genotype analysis of cryopyrin-associated periodic syndromes (CAPS): description of a rare non-exon 3 and a novel CIAS1 missense mutation.

We describe in this paper the phenotype-genotype analysis of a Brazilian cohort of patients with cryopyrin-associated periodic syndromes (CAPS). Patient 1 presented with an urticarial rash and recurrent fever exacerbated by cold weather, arthritis, and anterior uveitis, thus, receiving a clinical diagnosis of familial cold autoinflammatory syndrome. CIAS1 sequencing identified the T436I mutation, previously associated to a clinical phenotype of chronic infantile neurological cutaneous and articular/neonatal onset multisystem inflammatory disease. Patient 2 developed a papular exanthema with daily fever shortly after birth, frontal bossing, patellae enlargement, and cognitive and motor impairments. Sequencing identified the exceedingly rare G755R CIAS1 mutation in exon 4. Patient 3 developed skin rash and articular symptoms 6 h after birth, followed by aseptic meningitis. He was found to have the novel C148Y missense mutation in CIAS1. This report expands the spectrum of CIAS1 mutations associated to clinical disease, suggests that the same mutation can be associated with different clinical syndromes, and supports the evidence that CAPS patients should always be screened for mutations outside exon 3.

Membrane topology of a multidrug efflux transporter, AcrB, in Escherichia coli.

AcrA/B in Escherichia coli is a multicomponent system responsible for intrinsic resistance to a wide range of toxic compounds, and probably cooperates with the outer membrane protein TolC. In this study, acrAB genes were cloned from the E. coli W3104 chromosome. To determine the topology of the inner membrane component AcrB, we employed a chemical labeling approach to analyse mutants of AcrB in which a single cysteine residue had been introduced. The cysteine-free AcrB mutant, in which the two intrinsic Cys residues were replaced by Ala, retained full drug resistance. We constructed 33 cysteine mutants in which a single cysteine was introduced into each putative hydrophilic loop region of the cysteine-free AcrB. The binding of [(14)C]N-ethylmaleimide (NEM) to the Cys residue and the competition of NEM binding with the binding of a membrane-impermeant maleimide, 4-acetamide-4'-maleimidylstilbene-2,2'-disulfonic acid (AMS), in intact cells were investigated. The results revealed that the N- and C-terminals are localized on the cytoplasmic surface of the membrane and the two large loops are localized on the periplasmic surface of the membrane. The results supported the 12-membrane-spanning structure of AcrB. Three of the four short periplasmic loop regions were covered by the two large periplasmic loop domains and were not exposed to the water phase until one of the two large periplasmic loops was removed.