An atypical presentation of diabetic myonecrosis

Diabetic myonecrosis complicated by emphysematous pyomyositis and abscess caused by Escherichia coli: a case report

BACKGROUND

Necrotizing myopathies and muscle necrosis can be caused by immune-mediated mechanisms, drugs, ischemia, and infections, and differential diagnosis may be challenging.

CASE PRESENTATION

We describe a case of diabetic myonecrosis complicated by pyomyositis and abscess caused by Escherichia coli. A white woman in her late forties was admitted to the hospital with a 1.5 week history of bilateral swelling, weakness, and mild pain of the lower extremities and inability to walk. She had a history of type 1 diabetes complicated by diabetic retinopathy, neuropathy, nephropathy, and end-stage renal disease. C-reactive protein was 203 mg/l, while creatinine kinase was only mildly elevated to 700 IU/l. Magnetic resonance imaging of her lower limb muscles showed extensive edema, and muscle biopsy was suggestive of necrotizing myopathy with mild inflammation. No myositis-associated or myositis-specific antibodies were detected. Initially, she was suspected to have seronegative immune-mediated necrotizing myopathy, but later her condition was considered to be explained better by diabetic myonecrosis with multifocal involvement. Her symptoms alleviated without any immunosuppressive treatment. After a month, she developed new-onset and more severe symptoms in her right posterior thigh. She was diagnosed with emphysematous urinary tract infection and emphysematous myositis and abscess of the right hamstring muscle. Bacterial cultures of drained pus from abscess and urine were positive for Escherichia coli. In addition to abscess drainage, she received two 3-4-week courses of intravenous antibiotics. In the discussion, we compare the symptoms and findings typically found in pyomyositis, immune-mediated necrotizing myopathy, and diabetic myonecrosis (spontaneous ischemic necrosis of skeletal muscle among people with diabetes). All of these diseases may cause muscle weakness and pain, muscle edema in imaging, and muscle necrosis. However, many differences exist in their clinical presentation, imaging, histology, and extramuscular symptoms, which can be useful in determining diagnosis. As pyomyositis often occurs in muscles with pre-existing pathologies, the ischemic muscle has likely served as a favorable breeding ground for the E. coli in our case.

CONCLUSIONS

Identifying the etiology of necrotizing myopathy is a diagnostic challenge and often requires a multidisciplinary assessment of internists, pathologists, and radiologists. Moreover, the presence of two rare conditions concomitantly is possible in cases with atypical features.

Diabetic Muscle Infarction: An Uncommon Diabetic Complication With a Lack of Standardized Treatment

Diabetic muscle infarction (DMI) is a rare yet serious complication that has been strongly associated with uncontrolled diabetes, although other risk factors are unclear. DMI is an uncommon complication of diabetes with a lack of structured guidelines for evaluation or management. End-stage renal disease (ESRD) could have further implications in patients with DMI in terms of management given that nonsteroidal anti-inflammatory drugs (NSAIDs), which have been shown to reduce the recovery times and recurrence of DMI, could be contraindicated. We present a rare case of DMI in an African American man with ESRD who presented for new-onset right lower-extremity pain and swelling. We discuss the challenges involved with the diagnosis and treatment of this rare condition. This case adds to the knowledge of DMI, which is limited because of the low incidence of this condition, and it helps us understand how this condition affects the African American population and patients with ESRD.

A new therapeutic approach with tocilizumab in a 39-year-old patient with recurrent diabetic myonecrosis

We report the case of a 39-year-old female patient with acute painful swelling of the left thigh and symmetric muscle weakness in both upper legs. The patient had a history of long-standing, poorly controlled type 1 diabetes which required dialysis. Serum inflammatory markers were highly elevated. Magnetic resonance imaging (MRI) indicated necrotic or inflammatory colliquation. As antibiotic therapy did not lead to clinical improvement, a successful anti-inflammatory therapy with prednisolone was initiated. Three months later, the patient presented with a new onset of progressive and painful muscle swelling of the right thigh. MRI showed pronounced swelling of the right adductor muscles and inflammatory markers were massively elevated. In the absence of autoantibodies or any infectious agents and the recurrent symptomatology, relapsing diabetogenic myonecrosis was diagnosed. Initially, clinical improvement could only be achieved with high-dose glucocorticosteroids. Intravenous immunoglobulins did not show an effect, whereas serological and clinical remission was achieved after we administered tocilizumab intravenously. Diabetic myonecrosis is a rare complication of long-term, poorly controlled diabetes mellitus. Acute muscle pain and elevated inflammatory markers should prompt suspicion. Contralateral muscle involvement is also suggestive of the disease. The optimisation of diabetes treatment is crucial in order to prevent further disease complications.

Upper-Limb Diabetic Myonecrosis: Atypical Presentation of a Rare Complication

BACKGROUND Myonecrosis is an uncommon complication of poorly controlled diabetes, predominantly involving the lower limbs. It is an atypical presentation in the upper limbs. Here, we report a rare case with atypical involvement of the upper limbs. CASE REPORT A 53-year-old diabetic woman presented with left arm pain for the past week. She was not compliant with her medications. The patient denied any history of trauma or injection. Physical examination revealed a warm, tender, and erythematous swelling on the medial side of the left arm and was otherwise unremarkable. Her glycemic control was poor, with Hb A1C of 9.6%. Duplex ultrasonography demonstrated no evidence of fluid collection or thrombosis. An initial MRI (without contrast) report was misleadingly suggestive of polymyositis. Orthopedic consultant urged the patient to transfer to the operating room for aspiration of a probable infectious nidus, which resulted in a dry tap. Despite confusing radiological clues, ischemic myonecrosis was suspected, and second MRI studies (with contrast) reported necrosis. Tissue biopsy (the criterion standard) was withheld to avoid the risk of delayed healing or superimposed infection. Meanwhile, the patient received supportive treatment and achieved full recovery within 1 month. CONCLUSIONS Diabetic myonecrosis should be suspected in any poorly controlled diabetic patient presenting with otherwise unexplained muscle pain without any evidence of infection. Diagnosis can be made by MRI, leaving very few indications for invasive procedures. Analgesics and glycemic control are the mainstays of treatment.