Osteomalacia oncogénica secundaria a tumor mesenquimal fosfatúrico del pie / Oncogenic osteomalacia secondary to phosphaturic mesenchymal tumour of the foot

RESUMEN La osteomalacia oncogénica es un síndrome metabólico paraneoplásico caracterizado por hipofosfatemia debida a la pérdida renal de fosfato, con nivel bajo de vitamina D. Este trastorno está asociado con la liberación de factores fosfatúricos por células tumorales, especialmente el factor de crecimiento fibrolástico 23 (FGF23). Las neoplasias relacionadas con la osteomalacia oncogénica suelen ser tumores pequeños de linaje mesenquimatoso y pueden ser difíciles de localizar en algunos casos debido a su tamaño y ubicación poco accesible al examen físico. Presentamos a un paciente que desarrolló fracturas vertebrales y de cadera debido a osteomalacia oncogénica asociada con un tumor mesenquimatoso fosfatúrico del tejido graso profundo de la planta del pie, que finalmente se diagnosticó después de 3 años del inicio de los síntomas, cuando el tumor pudo ser localizado por el rastreo gammagráfico óseo con pentatreótido marcado con indio-111 y por las imágenes de resonancia magnética nuclear.

ABSTRACT Oncogenic osteomalacia is a paraneoplastic metabolic syndrome characterised by a low phosphates in the blood due to renal phosphate losses with inadequately normal or low vitamin D levels. This disorder is associated with the release of tumour cell-secreted phosphaturic factor, most notably fibroblast growth factor 23 (FGF-23). The neoplasms related to oncogenic osteomalacia are usually small tumours of mesenchymal lineage, and they may be difficult to locate in the physical examination in some cases, due to their size and inaccessible location. The case is presented of a patient who developed vertebral and hip fractures due to oncogenic osteomalacia associated with a phosphaturic mesenchymal tumour of the deep fat tissue in the sole of the foot. This was finally diagnosed after 3 years of the onset of symptoms after being located by bone scintigraphy with Indium-111 labelled pentetreotide and magnetic resonance imaging.

Timing of onset affects arthritis presentation pattern in antisyntethase syndrome.

OBJECTIVES: To evaluate if the timing of appearance with respect to disease onset may influence the arthritis presentation pattern in antisynthetase syndrome (ASSD). METHODS: The patients were selected from a retrospective large international cohort of ASSD patients regularly followed-up in centres referring to AENEAS collaborative group. Patients were eligible if they had an antisynthetase antibody testing positive in at least two determinations along with arthritis occurring either at ASSD onset (Group 1) or during the course of the disease (Group 2). RESULTS: 445 (70%; 334 females, 110 males, 1 transsexual) out of the 636 ASSD we collected had arthritis, in the majority of cases (367, 83%) from disease onset (Group 1). Patients belonging to Group 1 with respect to Group 2 had an arthritis more commonly polyarticular and symmetrical (p=0.015), IgM-Rheumatoid factor positive (p=0.035), erosions at hands and feet plain x-rays (p=0.036) and more commonly satisfying the 1987 revised classification criteria for rheumatoid arthritis (RA) (p=0.004). Features such as Raynaud's phenomenon, mechanic's hands and fever (e.g. accompanying findings) were more frequently reported in Group 2 (p=0.005). CONCLUSIONS: In ASSD, the timing of appearance with respect to disease onset influences arthritis characteristics. In particular, RA features are more common when arthritis occurs from ASSD onset, suggesting an overlap between RA and ASSD in these patients. When arthritis appears during the follow-up, it is very close to a connective tissue disease-related arthritis. Also, the different prevalence of accompanying features between these two groups is in line with this possibility.

Spontaneous pneumomediastinum complicating interstitial lung disease, associated with clinically amyopathic dermatomyositis and positive anti-MDA5 antibodies / Neumomediastino espontáneo como complicación de enfermedad pulmonar intersticial, asociada con dermatomiositis clínicamente amiopática y anticuerpos anti-MDA5 positivos

Abstract Clinically amyopathic dermatomyositis comprises a special group of patients within the spectrum of dermatomyositis characterized by the presence of typical skin lesions, minimal or absent muscle involvement, and increased risk of interstitial lung disease. The antibodies directed against the protein encoded by melanoma differentiation-associated gene 5 (MDA5) are present in a significant proportion of patients with clinically amyopathic dermatomyositis, who develop rapidly progressive interstitial lung disease, with high mortality and frequently complicated by the onset of spontaneous pneumomediastinum. A case is presented of an African patient with anti-MDA5 positive clinically amyopathic dermatomyositis and interstitial lung disease with tomography pattern of organizing pneumonia who developed spontaneous pneumomediastinum during its clinical course.

Resumen La dermatomiositis clínicamente amiopática comprende un grupo especial de pacientes dentro del espectro de la dermatomiositis, caracterizados por la presencia de lesiones cutáneas típicas, compromiso muscular mínimo o ausente y riesgo aumentado de enfermedad pulmonar intersticial. Los anticuerpos dirigidos contra la proteína codificada por el gen asociado con la diferenciación del melanoma 5 (MDA5), están presentes en una proporción importante de pacientes con dermatomiositis clínicamente amiopática, los cuales desarrollan enfermedad pulmonar intersticial rápidamente progresiva, con elevada mortalidad y que se complica frecuentemente con la aparición de neumomediastino espontáneo. Presentamos el caso de una paciente de origen africano con dermatomiositis clínicamente amiopática anti-MDA5 positiva y enfermedad pulmonar intersticial con patrón tomográfico de neumonía organizada, que desarrolló neumomediastino espontáneo durante su evolución.