Spontaneous intramuscular hemorrhage in cancer-associated dermatomyositis: a case and literature review

Background: Dermatomyositis (DM) is a systemic autoimmune disease with characteristic cutaneous manifestations and muscle weakness of the trunk, symmetrical proximal muscles of the limbs. Spontaneous intramuscular hemorrhage (SIH) is a rare but life-threatening complication of DM. The pathogenetic mechanism and management of intramuscular hematoma in these patients remains unclear. Here we discuss a case of recurrent hemorrhage in a patient with DM, and reviews the relevant literature in order to make timely diagnosis and treatment. Case presentation: The patient is a 53-year-old male who presented with rashes, muscle weakness and dysphagia and was diagnosed with DM. During treatment, he developed SIH of the arm and right psoas major muscle, MRI showed extensive edema of the right shoulder girdle muscle and muscle groups of the upper arm, CT scan showed new-onset hematoma formation in the right psoas major muscle. The detection of D-dimer, TAT, PIC and t-PAIC indicated that he has thrombosis and hyperfibrinolysis. Blood transfusion and supportive treatment was immediately performed, the hematoma did not expand. Abdominal distension has not been relieved after active treatment. Electronic gastroscopy found gastric sinus ulcer, histopathology of biopsy showed signet-ring cell carcinoma. Conclusions: : Patients with cancer-associated DM have an increased risk of thrombosis, conventional anticoagulation therapy is not recommended. If the patient has a high risk of thrombosis and needs drug intervention, it is important to dynamic monitor the coagulation parameters during anticoagulation therapy. Especially when the D-dimer is high, it is uncertain whether the patient is in the state of thrombosis or hyperfibrinolysis, the detection of TAT, PIC, t-PAIC can help to determine whether to initiate anticoagulation therapy.