Franco J, Anaya J: The autoimmune tautology with a focus on antiphospholipid syndrome. Lupus 23: 1273, 2014.
Koike T: Antiphospholipid syndrome: 30 years and our contribution. Int J Rheum Disease 18: 233, 2015.
Miyakis M, Lockshin T, Atsumi D, et al: International consensus statement on an update of the classification criteria for definite antiphospholipid syndrome. J Thromb Haemost 4: 295, 2006.
Gerosa M, Meroni PL, Erkan D: Recognition and management of antiphospholipid syndrome. Curr Opin Rheumatol 28: 51, 2016.
Gomez-Puerta JA, Cervera R: Diagnosis and classification of the antiphospholipid syndrome. J Autoimmun 48: 20, 2014.
Lauvao LS, Goshima KR, Leon LR, et al: Superficial femoral artery thrombosis as a cause for distal embolism in primary antiphospholipid syndrome. J Vasc Surg 48: 47, 2008.
Amaya-Amaya J, Rojas-Villarraga A, Anaya JM: Cardiovascular disease in the antiphospholipid syndrome. Lupus 23: 1288, 2014.
Chen YG, Peng CK, Dai MS, et al: Reconcilable differences: idiopathic antiphospholipid syndrome. Am J Med 128: 471, 2015.
Giannakopoulos B, Krilis SA: The pathogenesis of the antiphospholipid syndrome. N Engl J Med 368: 1033, 2013.
de Groot PG, Urbanus RT: Antiphospholipid syndrome: not a noninflammatory disease. Semin Thromb Hemost 41: 607, 2015.
Lally L, Sammaritano L: Vasculitis in antiphospholipid syndrome. Rheum Dis Clin North Am 41: 109, 2015.
Davies GE, Triplett DA: Corticosteroid-associated blue toe syndrome: role of antiphospholipid antibodies. Ann Intern Med 113: 893, 1990.
Merashli M, Noureldine MHA, Uthman I, et al: Antiphospholipid syndrome: an update. Eur J Clin Invest 45: 653, 2015.
Yin H, Orietta BM, Delgado-Vega AM, et al: Association of STAT4 and BLK, but not BANK1 or IRF5, with primary antiphospholipid syndrome. Arthritis Rheum 60: 2468, 2009.
Cervera R, Serrano R, Pons-Estel G, et al: Morbidity and mortality in the antiphospholipid syndrome during a 10-year period: a multicenter prospective study of 1000 patients. Ann Rheum Dis 74: 1011, 2015.
Cervera R, Piette JC, Font J, et al: Antiphospholipid syndrome: clinical and immunologic manifestations and patterns of disease expression in a cohort of 1, 000 patients. Arthritis Rheum 46: 1019, 2002.
Lim W: Thrombotic risk in the antiphospholipid syndrome. Semin Thromb Hemost 40: 741, 2014.
Galli M: Treatment of the antiphospholipid syndrome. Auto Immun Highlights 5: 1, 2013.
Kazzaz NM, McCune WJ, Knight JS: Treatment of catastrophic antiphospholipid syndrome. Curr Opin Rheumatol 28: 218, 2016.
O'Keeffe ST, Woods BO, Breslin DJ, et al: Blue toe syndrome causes and management. Arch Intern Med 152: 2197, 1992.
Hirschmann JV, Raugi GJ: Blue (or purple) toe syndrome. J Am Acad Dermatol 60: 1, 2009.
Wingo JP, Nix ML, Greenfield LJ, et al: The blue toe syndrome: hemodynamics and therapeutic correlates of outcome. J Vasc Surg 3: 475, 1986.
Karmody AM, Powers SR, Monaco VJ, et al: Blue toe syndrome: an indication for limb salvage surgery. Arch Surg 111: 1263, 1976.
Belsky J, Alvey H, Bencze ATB, et al: Blue toe syndrome, ischemic pain treated with digital block. Emerg Med Clin North Am 10: 637, 2015.
Abdelmalek MF, Spittell PC: 79-year-old woman with blue toes. Mayo Clin Proc 70: 292, 1995.
Sharifkazemi MB, Zamirian M, Aslani A: Blue toe syndrome. J Cardiovasc Surg 8: 975, 2007.
Lee BY, Brancato RF, Thoden WR, et al: Blue digit syndrome: urgent indication for digital salvage. Am J Surg 147: 418, 1984.
Choi KH, Yoo J, Huh JW, et al: Blue toe syndrome as an early sign of disseminated intravascular coagulation. Ann Dermatol 28: 400, 2016.
Pengo V, Banzato A, Bison E, et al: Labratory testing for antiphospholipid syndrome. Int J Lab Hematol 38: 1, 2016.
Noureldine M, Khamashta M, Merashli M, et al: Musculoskeletal manifestations of the antiphospholipid syndrome. Lupus 25: 451, 2016.
Lim W: Antiphospholipid syndrome. Hematology 15: 675, 2013.
Andrade D, Tektonidou M: Emerging therapies in antiphospholipid syndrome. Curr Rheumatol Rep 18: 22, 2016.
Pericleous C, Rahman A: Domain I: the hidden face of antiphospholipid syndrome. Lupus 23: 1320, 2014.
Schattner A, Teshler M, Kozac N: Odd spot for a clot: primary antiphospholipid syndrome. Am J Med 126: 217, 2013.
Antiphospholipid syndrome is an autoimmune disease characterized by vascular thrombosis involving both the arterial and venous systems that can lead to tissue ischemia or end-organ damage. Much of the literature describes various symptoms at initial presentation, but isolated tissue ischemia manifesting as a solitary blue toe is unusual. We discuss a case of a 23-year-old man who presented to the emergency department with a solitary blue fourth digit with minimal erythema and edema, who was suffering from exquisite pain. Following an extensive workup, the patient was diagnosed with antiphospholipid syndrome with thrombi of the vasculature in their lower extremity. With therapeutic anticoagulation, the patient's symptoms subsided and amputation of the digit was prevented.