Two case reports of distal upper limb weakness following influenza-like illness: an emerging pattern of para-infectious myositis in adults

Abstract

Background: Myositis is a recognised complication of numerous systemic viral infections including influenza. In adults the typical pattern is characterised by myalgia and marked proximal muscle weakness in upper and lower limbs and resolves slowly over weeks rather than days. Case presentation: Here, we describe two male patients with myositis with an unusual distribution of weakness in the distal upper limbs, which both followed a flu-like illness and resolved spontaneously. Both patients had moderate elevations in creatine kinase, extensive negative serological investigations, normal nerve conduction studies and myopathic changes on electromyography. Conclusions: In the para-infectious context, myositis is an important differential of acute distal upper limb weakness. This unusual pattern of acute muscle weakness should be recognised to avoid unnecessary in treatments. Similar cases in the recent literature in male patients between the ages of 25 to 55 are reviewed and suggest an emerging pattern of para-infectious myositis.

Acute distal and symmetrical myositis of uncertain aetiology-a case report and literature review

“…24 These cases present with a prodromal phase of myalgia followed by involvement of variable patterns of muscle distribution of both upper and lower limbs. 9 The clinical presentation of our case does not t with any of the known subgroups of myositis detailed in Table 1. It lacks the systemic involvement of DM, not typical clinical features of ADM, not the typical proximal distribution of PM, no drug history to suggest NM or the typical age of JM.…”

“…Scaber et al suggested an emerging pattern of para-infectious myositis in adults. 9 They described acute myositis in two male patients with an unusual distribution of weakness in the distal upper limbs, which both followed a u-like illness and resolved spontaneously. The rst case was 38 and the second was 54 years old.…”

Influenza A (H1N1) Encephalitis with Right Axillary Nerve Lesion

“…Bilateral upper extremity weakness, and bilateral hand weakness due to myositis, and bilateral femoral nerve compression due to rhabdomyolysis have been reported. [5][6][7] Although incidence of neurological complications is not definitely known it is predicted to be 4 per 100,000 children in a year. 1 There is no marker to predict the development of neurological complications in patients with influenza-like symptoms.…”