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Life-Threatening Hypercalcemia Revealing Diffuse and Isolated Acute Sarcoid-Like Myositis: A New Entity? (A
Arthur Mageau1, Aude Rigolet, Khadija Benali
1From the Département de Médecine Interne, Hôpital Bichat, Université Paris Diderot, PRES Sorbonne Paris Cité, Assistance Publique Hôpitaux de Paris (AM, MPC, TP, KS); Département de Médecine Interne, Centre de référence de pathologie neuromusculaire, Hôpital Pitié-Salpêtrière, Université Pierre et Marie Curie, Assistance Publique Hôpitaux de Paris (AR); Département de Médecine Nucléaire (KB); Département de Médecine Interne, Hôpital Saint Antoine, Université Pierre et Marie Curie, Assistance Publique Hôpitaux de Paris (MC); Département de Radiologie (SL), Hôpital Bichat, Université Paris Diderot, PRES Sorbonne Paris Cité, Assistance Publique Hôpitaux de Paris; Département de Médecine Interne, Hôpital Louis Mourier, Université Paris Diderot, PRES Sorbonne Paris Cité, Assistance Publique Hôpitaux de Paris, EA REMES 7334 Recherche Clinique ville-hôpital, Méthodologies et Société (IM); Département de Neuropathologie et Neurophysiologie, Hôpital Pitié-Salpêtrière, Université Pierre et Marie Curie, Assistance Publique Hôpitaux de Paris (TM); Département Hospitalo-Universitaire FIRE (Fibrosis, Inflammation and Remodelling in Renal and Respiratory Diseases), Université Paris Diderot, PRES Sorbonne Paris Cité (TP, KS); and INSERM U1149, Université Paris Diderot, Laboratoire d'excellence INFLAMEX, PRES Sorbonne Paris Cité (TP, KS), Paris, France.
Abstract:
Up to 50% patients with sarcoidosis display extra-pulmonary disease. However, initial and isolated (ie, without lung disease) acute muscular involvement associated with pseudo-malignant hypercalcemia is very uncommon. We report on 3 cases of life-threatening hypercalcemia revealing florid and isolated acute sarcoid-like myositis.All patients complained of fatigue, progressive general muscle weakness, and weight loss. Laboratory tests showed a severe life-threatening hypercalcemia (>3.4 mmol/L). Hypercalcemia was associated with increased serum level of 1,25-(OH)2 vitamin D and complicated with acute renal failure. One patient displayed acute pancreatitis due to hypercalcemia.In all cases, PET-scan, performed for malignancy screening, incidentally revealed an intense, diffuse, and isolated muscular fluorodeoxyglucose (FDG) uptake consistent with diffuse non-necrotizing giant cells granulomatous myositis demonstrated by muscle biopsy. Of note, creatine phosphokinase blood level was normal in all cases. No patients displayed the usual thoracic features of sarcoidosis.All patients were treated with high dose steroids and achieved rapid, complete, and sustained remission. A review of English and French publications in Medline revealed 5 similar published cases.Steroid-sensitive acute sarcoid-like myositis causing high calcitriol levels and life-threatening hypercalcemia should be recognized as a separate entity.
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