To the Editor:
Raynaud phenomenon (RP) is an episodic vasospasm of the digits that can lead to ulceration, gangrene, and autoamputation with prolonged ischemia. OnabotulinumtoxinA has been implemented as a treatment of intractable RP by paralyzing the muscles of the digital arteries. We report a case of a woman with severe RP secondary to systemic lupus erythematosus (SLE) who was treated with onabotulinumtoxinA injections after multiple treatment modalities failed to improve her condition. We describe the dosage and injection technique used to produce clinical improvement in our patient and compare it to prior reports in the literature.
A 33-year-old woman presented to the emergency department for worsening foot pain of 5 days' duration with dusky purple color changes concerning for impending Raynaud crisis related to RP. The patient had a history of antiphospholipid antibody syndrome (APS) and SLE with overlapping symptoms of polymyositis and scleroderma. She had been hospitalized for RP multiple times prior to the current admission. She was medically managed with nifedipine, sildenafil, losartan potassium, aspirin, alprostadil, and prostaglandin infusions, and was surgically managed with a right-hand sympathectomy and right ulnar artery bypass graft that had subsequently thrombosed. At the current presentation, she had painful dusky toes on both feet though more pronounced on the left foot. She endorsed foot pain while walking and tenderness to palpation of the fingers, which were minimally improved with intravenous prostaglandins.
Physical examination revealed blanching of the digits in both hands with pits in the right fourth and left first digits. Dusky patches overlaid all the toes as well as the superior plantar aspects of the feet (Figure 1). Given the history of APS, a punch biopsy was performed on the left medial plantar foot and results showed no histologic evidence of vasculitis or vasculopathy. Necrotic foci were present on the left and right second metatarsal bones, which were not reperfusable (Figure 2). The clinical findings and punch biopsy results favored RP as opposed to vasculopathy from APS.
FIGURE 1. A and B, Dusky patches on the dorsal aspect of the toes as well as the superior plantar aspect of the feet, respectively, at presentation.
Several interventions were attempted, and after 4 days with no response, the patient agreed to receive treatment with onabotulinumtoxinA. OnabotulinumtoxinA (5 U) was injected into the subcutaneous tissue of the medial and lateral aspects of each of the first and second toes near the proximal phalanges (40 U total). However, treatment could not be completed due to severe pain caused by the injections despite preprocedure regional nerve blocks to both lower extremities, preinjection icing, and lorazepam. Two days later, the patient tolerated onabotulinumtoxinA injections of all remaining digits of both feet (60 U total). She noted slight clinical improvement soon thereafter. One week after treatment of all 10 toes, she reported decreased pain and reduced duskiness of both feet (Figure 3).
FIGURE 2. Punch biopsy of the left medial plantar foot at a site of several dusky patches showed no vasculitis or vasculopathy (H&E, original magnification ×20).
One month later, the patient endorsed recurring pain in the hands and feet. Physical examination revealed reticular cyanosis and increased violaceous patches of the hands; the feet were overall unchanged from the prior hospitalization. At 4-month follow-up, there was gangrene on the left second, third, and fifth toe in addition to areas of induration noted on the fingers. She was repeatedly hospitalized over the next 6 months for pain management and gangrene of the toes, and finally underwent an amputation of the left and right second toe at the proximal and middle phalanx, respectively. She currently is continuing extensive medical management for pain and gangrene of the digits; she has not received additional onabotulinumtoxinA injections.
FIGURE 3. A and B, Reduced duskiness of both feet was demonstrated at 1-week posttreatment with onabotulinumtoxinA injections.
Raynaud phenomenon is a vascular disorder characterized by intermittent arteriolar vasospasm of the digits, often due to cold temperature or stress. Approximately 90% of RP cases are primarily idiopathic, with the remaining cases secondary to other diseases, typically systemic sclerosis, SLE, or mixed connective tissue disease.1 Symptoms present with characteristic changing of hands from white (ischemia) to blue (hypoxia) to red (reperfusion). Episodic attacks of vasospasm and ischemia can be painful and lead to digital ulcerations and necrosis of the digits or hands. Other complications including digital tuft pits, pterygium inversum unguis, or torturous nail fold capillaries with capillary dropout also may be seen.2
Although the etiology is multifactorial, the pathophysiology primarily is due to an imbalance of vasodilation and vasoconstriction. Perturbed levels of vasodilatory mediators include nitric oxide, prostacyclin, and calcitonin gene-related peptide.3 Meanwhile, abnormal neural sympathetic control of α-adrenergic receptors located on smooth muscle vasculature and subsequent endothelial hyperproliferation may contribute to inappropriate vasoconstriction.4