A 28-year-old man presented with fever, myalgia and swelling of the left forearm. The history was remarkable for cystic fibrosis, pulmonary and renal transplants complicated by rejection, compensated diabetes mellitus, and hemodialysis fistula on the left forearm. Two days later, the fever disappeared, but the patient complained of sudden onset diplopia and left ocular pain. Neurologic examination revealed a left abduction deficit, consistent with left abducens nerve palsy (Fig. 1a).

Fig. 1
figure 1

Clinical presentation: left abducens nerve palsy (a). Axial T2-BLADE MRI image of the mid left forearm shows diffuse swelling and hyperintensity of the muscles and subcutaneous tissue consistent with inflammatory oedema (b)

Full size image

Pharmacologic history included mycophenolate mofetil, tacrolimus, prednisone, antihypertensive drugs, and insulin. Blood studies showed high CRP (9.38 mg/dl; n.v. <0.5) and procalcitonin (95.56 ng/ml; n.v. 0.002–0.06). Blood cultures were negative. Treatment with daptomycin 6 mg/kg/day every other day and meropenem 1 g/day was started. Viral and antibody testing were negative. A brain MRI without contrast was normal. T2-weighted MRI of the left forearm revealed hyperintensity of the muscular and subcutaneous tissues, consistent with inflammatory edema (Fig. 1b). Two weeks later, blood studies showed normal CRP (0.42 mg/dl; n.v. <0.5) and near normal procalcitonin (2.57 ng/ml; n.v. 0.02–0.06). Six weeks later, ocular motility was normal, and an MRI of the left forearm showed reduction of muscle edema. The sixth cranial nerve (abducens nerve) innervates the lateral rectus muscle, which is responsible for abducting the eye [1]. Abducens nerve palsies occur more frequently in children while they are unusual in young adults [2, 3]. The leading causes of acquired abducens nerve palsy are neoplasm and trauma [2, 4]. Inflammatory palsies are less frequent and can recover after appropriate treatment, as was the case in our patient [2].