Background The coexistence of infection and anti-phospholipid syndrome (APS) has been increasingly reported in the literature under the assumption that infection may be a triggering factor for the development of APS.
Objectives To conduct a systematic review of case reports documenting the development of primary APS after a prior infection, and to describe and categorize the clinical and immunological phenotypes in these cases.
Methods We conducted a comprehensive search in electronic databases from inception through October 2013 (Medline, EMBASE, Web of Science, and CENTRAL). We selected publications of case reports: 1) describing APS development after an infection; and 2) published in English, French, or Spanish. Study selection, quality appraisal, and data extraction were performed by two independent researchers. We extracted data on the potentially putative infection, the cases' clinical presentation, and their anti-phospholipid antibodies (APL Ab) profiles.
Results Out of 2,278 citations, only 200 case reports met our inclusion criteria. Two different groups of patients were identified. The first group included patients who presented with specific clinical and immunological findings that fulfilled the diagnostic criteria of primary APS after a definite history with documentation of preceding infection. Various types of bacterial (including spirochetal), viral, parasitic, and fungal infections were reported as preceding or triggering APS. Most commonly reported infections involved Human Immunodeficiency Virus (HIV), hepatitis C virus (HCV) and Mycoplasma pneumonia. Thromboembolic events included neurological, respiratory, and peripheral thrombosis, often with persistent positive APL Ab. The second group included patients who did not fulfil the criteria for diagnosis of APS, but developed transient positive autoimmune APL Ab after an infection. Among this group, 60% developed thromboembolic attacks during the course of the infection, with or without other coagulation disorders. In these latter cases the causal relationship between the development of antibodies and thrombosis was not clearly established, since thrombotic events could also be attributed to the infection itself, or a separate co-existent hypercoagulable state.
Conclusions This review found many reports of APS or APL Ab occurring after a variety of infections, including bacterial, viral, fungal and parasitic agents. A causal relationship cannot be established with these data, but the evidence supports that further longitudinal studies should be conducted to identify the risk of APS after infection with these agents.
Acknowledgements Dr. Suarez-Almazor is the recipient of a K24 career award from the National Institute for Musculoskeletal and Skin Disorders.
Disclosure of Interest : None declared