Familial pulmonary fibrosis: a heterogeneous spectrum of presentations / Fibrose pulmonar familiar: um espectro heterogêneo de apresentações

ABSTRACT Objective: To describe the clinical, functional, and radiological features of index cases of familial pulmonary fibrosis (FPF) in Brazil. Methods: We evaluated 35 patients with FPF - of whom 18 (51.4%) were women - with a median age of 66.0 years (range, 35.5-89.3 years). All of the patients completed a standardized questionnaire, as well as undergoing pulmonary function tests and HRCT of the chest. In 6 cases, lung tissue samples were obtained: from surgical biopsies in 5 cases; and from an autopsy in 1 case. Results: A history of smoking and a history of exposure to birds or mold were reported in 45.7% and 80.0% of the cases, respectively. Cough and marked dyspnea were reported by 62.8% and 48.6% of the patients, respectively. Fine crackles were detected in 91.4% of the patients. In 4 patients, the findings were suspicious for telomere disease. The median FVC and DLCO, as percentages of the predicted values, were 64.9% (range, 48.8-105.7%) and 38.9% (range, 16.0-60.0%), respectively. Nine patients had reduced DLCO despite having normal spirometry results. Regarding HRCT, patterns typical of usual interstitial pneumonia were found in 6 patients (17.1%). In 25 cases (71.5%), the HRCT features were consistent with a diagnosis other than idiopathic pulmonary fibrosis. In 11 cases (31.4%), the radiological patterns were uncharacteristic of interstitial lung disease. Of the six lung tissue samples analyzed, four showed interstitial pneumonia with bronchiolocentric accentuation, and, on the basis of the clinical and radiological data, the corresponding patients were diagnosed with hypersensitivity pneumonitis. Conclusions: Patients with FPF can present with a wide variety of clinical features. Most HRCT scans of these patients exhibit patterns not typical of usual interstitial pneumonia. The family history of fibrotic lung diseases should be investigated in all patients under suspicion, regardless of their age.

RESUMO Objetivo: Descrever as características clínicas, funcionais e radiológicas de um grupo de casos índice diagnosticados com fibrose pulmonar familiar (FPF) no Brasil. Métodos: Trinta e cinco pacientes com FPF (18 mulheres; 51,4%), com mediana de idade de 66,0 anos (variação: 35,5-89,3 anos), responderam a um questionário padronizado e foram submetidos a testes de função pulmonar e TCAR de tórax. Tecido pulmonar foi obtido para revisão em 6 casos: a partir de biópsias cirúrgicas em 5 e de autópsia em 1. Resultados: Antecedentes de tabagismo e de exposição a aves ou mofo foram referidos por 45,7% e 80,0% dos casos, respectivamente. Tosse e dispneia significante foram referidas por 62,8% e 48,6% dos pacientes, respectivamente. Estertores finos foram detectados em 91,4% dos indivíduos. Em 4 pacientes, os achados levantaram suspeitas de doença dos telômeros. As medianas da CVF e da DLCO foram, respectivamente, de 64,9% (variação: 48,8-105,7%) e 38,9% (variação: 16,0-60,0%) em porcentagem dos valores previstos. Apesar de espirometria normal, 9 pacientes exibiram DLCO reduzida. Em relação às TCAR, padrões típicos de pneumonia intersticial usual foram encontrados em 6 pacientes (17,1%). Em 25 casos (71,5%) os achados tomográficos foram mais consistentes com um diagnóstico de não relacionado a fibrose pulmonar idiopática. Em 11 pacientes (31,4%) o padrão radiológico foi incaracterístico para doença pulmonar intersticial. Das seis amostras de tecido pulmonar analisadas, quatro mostraram pneumonias intersticiais com acentuação bronquiolocêntrica e, em função de outros dados clínicos e radiológicos, pneumonite de hipersensibilidade foi diagnosticada. Conclusões: Pacientes com FPF podem apresentar características clínicas diversas. A maioria das TCAR desses pacientes exibe padrões não típicos de pneumonia intersticial usual. A pesquisa da história clínica de outros casos de pneumopatias fibrosantes na família deve ser feita em todos os pacientes em investigação, independentemente da idade.

THPO gene variants in patients with acquired aplastic anemia

ABSTRACT Background: Human aplastic anemia is a hematologic disease characterized by low peripheral blood cell counts associated with reduced numbers of hematopoietic stem and progenitor cells and a hypocellular bone marrow. Thrombopoietin (THPO) regulates megakaryocytes, but it also stimulates hematopoietic stem and progenitor cells. Biallelic mutations in the THPO gene have been reported in a family with recessive inherited aplastic anemia. Methods: This study screened 83 patients diagnosed with acquired aplastic anemia and 92 paired healthy controls for germline variants in the THPO gene using Sanger sequencing. Results: Three common single nucleotide polymorphisms were identified in patients and controls at comparable allele frequencies. There was no correlation between the single nucleotide polymorphism carrier status and platelet counts at diagnosis. Conclusion: The presence of THPO polymorphisms is comparable between patients with acquired aplastic anemia and healthy individuals.

Splicing factor SF3B1 mutations and ring sideroblasts in myelodysplastic syndromes: a Brazilian cohort screening study

ABSTRACT Background: Myelodysplastic syndromes (MDS) comprise a group of malignant clonal hematologic disorders characterized by ineffective hematopoiesis and propensity for progression to acute myeloid leukemia. Acquired mutations in the gene encoding RNA splicing factor 3B subunit 1 (SF3B1) are highly associated with the MDS subtypes presenting ring sideroblasts, and represent a specific nosological entity. The effects of these mutations on clinical outcomes are diverse and contrasting. Methods: A cohort of 91 Brazilian MDS patients, including patients with ring sideroblasts in the bone marrow, were screened for mutations in the SF3B1 hotspots (exons 12-15) by direct Sanger sequencing. Results: SF3B1 heterozygous mutations were identified in six patients (7%), all of them with ring sideroblasts, thus confirming the association between SF3B1 mutations and myelodysplastic syndrome subtypes bearing this morphologic feature (frequency of 6/13, p-value < 0.0001). Conclusion: This is the first screening of SF3B1 mutations in a cohort of Brazilian myelodysplastic syndrome patients. Our findings confirm that mutations in this splicing gene correlate with bone marrow ringed sideroblasts.

Shwachman-Diamond syndrome: first molecular diagnosis in a Brazilian child

Herein the first molecular diagnosis of a Brazilian child with Shwachman-Diamond Syndrome is reported. A 6-year-old boy was diagnosed with cystic fibrosis at the age of 15 months due to recurrent respiratory infections, diarrhea and therapeutic response to pancreatic enzymes. Three sweat tests were negative. At the age of 5 years, he began to experience pain in the lower limbs, laxity of joints, lameness and frequent falls. A radiological study revealed metaphyseal chondrodysplasia. A complete blood cell count showed leukopenia (leukocytes: 3.1-3.5 x 103/µL), neutropenia (segmented neutrophils: 15-22%), but normal hemoglobin, hematocrit and platelet count. A molecular study revealed biallelic mutations in the Shwachman-Bodian-Diamond Syndrome gene (183-184TA-CT K62X in exon 2 and a 258+2T-C transition) confirming the diagnosis of Shwachman-Diamond Syndrome. A non-pathologic, silent nucleotide A to G transition at position 201 was also found in heterozygosis in the Shwachman-Bodian-Diamond Syndrome gene. This is the first report to describe a Brazilian child with molecular diagnosis of Shwachman-Diamond Syndrome, a rare autosomal recessive disorder characterized by exocrine pancreatic insufficiency, intermittent or persistent neutropenia and skeletal changes. Other characteristics include immune system, hepatic and cardiac changes and predisposition to leukemia. Recurrent bacterial, viral and fungal infections are common. The possibility of Shwachman-Diamond Syndrome should be kept in mind when investigating children with a diagnosis of cystic fibrosis and normal sweat tests.