Antiphospholipid syndrome is a state of autoimmune-induced hypercoagulability. The uncharacteristically hyperbolic term "catastrophic" is used to describe a case of antiphospholipid syndrome which involves both excessive clotting and excessive bleeding, with consumption of coagulation factors. Like most medical conditions with the words "catastrophic" in the title, the ICU trainee should have wanted to be familiar with this syndrome, even though it had previously never appeared in the fellowship exam papers. And then of course it did appear, as Question 11 from the second paper of 2022, and predictably only 9.6% of the trainees were able to pass this question (even with Angoff marking, which would have lowered the expected pass mark). Non-catastrophic antiphospholipid syndrome has also appeared as a third of Question 7 from the first paper of 2022.
If the time-poor trainee were going to devote any of their precious time to reading about this disease process, they may wish to limit thremselves to only one paper.
That paper should be the 2012 update by Cervera and Espinosa. Unless otherwise stated, everything that follows in this summary is a concentrated distillate of their wisdom. Other more recent resources include Garcia & Erkan (2018).
One would confirm this diagnosis by ordering a lupus anticoagulant and an antiphospolipid antibody assays. Certainly, one could spend hours talking about esoterica like the Russel Viper Venom Time. Instead, I will point to the most recent consensus statement regarding the diagnostic criteria. One requires one clinical criterion (eg. thrombosis) and one laboratory criterion (eg. a positive anti-β2-glycoprotein-I antibody) for a diagnosis of antiphospholipid syndrome, and a few other features to make it "catastrophic".
The complete list of criteria is as follows:
"Definite" CAPS satisfies all 4 criteria, but one wonders whether histopathological confirmation is a sensible criterion to demand. "Probable" CAPS satisfies criteria 1, 2 and 4.
The antiphospholipid syndrome patient is prone to simultaneously clotting and bleeding. The specific list of complication and clinical features depends on the organs most affected. They may include the following:
The CAPS registry (consisting of 280 patients) records the following patterns:
Laboratory features, beyond the serology required for diagnosis, include the following:
Management strategies consist of anticoagulation and immunosuppression, with a stepwise escalation of therapies all the way up to weird stuff like ancrod and various mibs and mabs.
Second line therapies:
Third line therapies:
Garcia, David, and Doruk Erkan. "Diagnosis and management of the antiphospholipid syndrome." New England Journal of Medicine 378.21 (2018): 2010-2021.
Cervera, Ricard. "Antiphospholipid syndrome." Thrombosis research 151 (2017): S43-S47.
Miyakis, Spyridon, et al. "International consensus statement on an update of the classification criteria for definite antiphospholipid syndrome (APS)." Journal of Thrombosis and Haemostasis 4.2 (2006): 295-306.
Cervera, Ricard, and Gerard Espinosa. "Update on the catastrophic antiphospholipid syndrome and the “CAPS Registry”." Seminars in thrombosis and hemostasis. Vol. 38. No. 4. 2012.
Belmont, H. Michael. "Catastrophic antiphospholipid syndrome." Hughes Syndrome. Springer London, 2006. 171-180.
Mehta, Trupti P., Maureen A. Smythe, and Joan C. Mattson. "Strategies for managing heparin therapy in patients with antiphospholipid antibody syndrome." Pharmacotherapy: The Journal of Human Pharmacology and Drug Therapy 31.12 (2011): 1221-1231.