Diplopia and myalgia: potential heralding symptoms of polyarteritis nodosa

Polyarteritis nodosa initially presenting as ocular motility impairment and diplopia with subsequent development of bilateral central retinal artery occlusion: A case report

Purpose

Polyarteritis nodosa (PAN) is a systemic vasculitis of unknown etiology affecting medium- and small-sized arteries and can present with varied organ involvement, including ocular manifestations. Here, we report a unique case of PAN that initially presented with diplopia and ocular motility impairment, with subsequent development of bilateral central retinal artery occlusion (CRAO), a rare ocular manifestation of PAN.

Observations

A 58-year-old man presented with left abduction impairment and diplopia, which initially improved without intervention. However, similar symptoms recurred in the right eye later. The patient presented to the ophthalmology department and was initially suspected of having orbital myositis related to IgG4 disease owing to elevated IgG4 levels. Subsequently, the patient developed bilateral CRAO, confirmed using fundus fluorescein angiography, resulting in remarkable visual loss. Despite negative autoantibodies, a high inflammatory response, and symptoms suggestive of systemic involvement (myalgia, hematuria, muscle weakness, and gastrointestinal symptoms), PAN was diagnosed following laparotomy for intestinal perforation, revealing vasculitis in the medium-to-small arteries.

Conclusions and importance

This case underscores the importance of considering a possible diagnosis of PAN in patients with ocular motility impairments and diplopia, even in the absence of classic systemic symptoms. PAN can rapidly progress to severe visual dysfunction, including bilateral CRAO, as observed in this case. Consequently, early recognition and treatment of PAN are crucial, given its potentially severe complications and poor prognosis. Further, this report contributes to the limited literature on PAN, emphasizing the need for awareness of the rare ocular manifestations of systemic vasculitis.

Severe Disabling Myalgia as an Initial Presentation of Polyarteritis Nodosa

BACKGROUND

Polyarteritis nodosa (PAN) is a form of necrotizing vasculitis affecting medium or small blood vessels with multiorgan involvement. Although myalgia is a clinical feature of PAN, severe disabling myalgia as the initial presentation is rarely noted.

CASE PRESENTATION

We present a case of 54-year-old male with recently detected chronic kidney disease admitted with progressive severe disabling muscular pains predominantly over calves with constitutional symptoms for seven weeks. He was weak to mobilize out of the bed. Later, he developed a vasculitic rash, unilateral ulnar claw, and bilateral foot drop. His skin and muscle biopsies showed evidence of vasculitis. His renal and mesenteric artery CT angiogram revealed stenosed segment of the celiac artery without evidence of visible aneurysms elsewhere. He completed six cycles of intravenous cyclophosphamide pulse therapy with high-dose oral prednisolone with good response. With continuation of aggressive immunosuppression and rehabilitation for five months, the patient improved and was able to walk without support.

CONCLUSION

Musculoskeletal predominant PAN, even though rare, needs to be considered in patients presenting with disabling muscle pain and weakness. These features may herald over days to months along with constitutional symptoms before other systems getting affected. Early recognition of such symptoms and initiating specific treatment would be important for better outcomes.