Autoimmune and autoinflammatory diseases

Systemic autoimmune diseases

Systemic autoimmune diseases affect several organs at once, which is why they belong to internal medicine rather than to an organ specialty. This page describes those that are followed in the department and develops the subjects on which work has been published, first among them Cogan's syndrome, for which Arsène Mekinian coordinated the French national diagnosis and care protocol.

What is a systemic autoimmune disease?

In a systemic autoimmune disease, the immune system attacks the body it should be protecting, and it does so in several organs at the same time. It is this diffuse character that distinguishes them from autoimmune diseases of a single organ and that explains why they are managed by internal medicine: the work consists first in assembling scattered signs, involvement of the skin, the joints, the blood, the lungs, the kidneys, the eye or the ear, into a single diagnosis, then in coordinating the specialties concerned. This page covers systemic lupus, Sjögren's syndrome, myositis, autoimmune cytopenias, bradykinin-mediated angioedema and Cogan's syndrome. Systemic sclerosis, large-vessel vasculitis, antiphospholipid syndrome, VEXAS syndrome and the autoinflammatory diseases have their own pages.

Cogan's syndrome holds a particular place on this page, because it is the disease of the field on which the published work is the most substantial. It is a rare inflammatory disease, classified among the vasculitides, which combines involvement of the eye, most often an inflammation of the cornea called interstitial keratitis, and involvement of the inner ear, with vertigo, tinnitus and rapid loss of hearing. No laboratory test confirms it: the diagnosis is made by ruling out other causes, and it is the hearing involvement, which may become permanent, that governs prognosis. It should not be confused with two other entities that carry the same family name, Cogan-Reese syndrome, which is a disease of the iris, and Cogan type oculomotor apraxia, which is a neurological disease of childhood. Bradykinin-mediated angioedema, another subject developed here, consists of sudden swellings of the skin and mucous membranes due to a molecule called bradykinin, without urticaria and without response to allergy treatments, which distinguishes them from allergic oedema. Autoimmune cytopenias, finally, are destructions by the immune system of the blood cells, platelets, red cells or white cells.

His work on this subject

Cogan's syndrome. The French national diagnosis and care protocol devoted to Cogan's syndrome was published online by the Haute Autorité de santé on 22 April 2024. It was drawn up under the aegis of the reference centre for autoinflammatory diseases and inflammatory amyloidosis (CeRéMAIA) and of the rare autoimmune and autoinflammatory disease network (FAI²R). The page that the FAI²R network devotes to this text states that "it was written under the coordination of Pr Arsène MEKINIAN" [A]. The page of the Haute Autorité de santé states for its part that the protocol was drawn up using a methodology it proposes, but that it did not take part in its preparation and did not validate it [B]. The published version of the protocol appeared in English in La Revue de médecine interne in February 2025, under the title French protocol for diagnosis and management of Cogan's syndrome; the MEDLINE record classes it as a Practice Guideline, it carries 26 named authors, Arsène Mekinian is the 26th and last, and he is its corresponding author 1. Six of the 26 signatories work in the department of internal medicine of Saint-Antoine Hospital according to the addresses in the record. The published text describes the disease as a systemic vasculitis of unknown origin, with a sex ratio close to one, whose most frequent manifestations are ocular and cochleovestibular; it states that 30 to 70% of patients have general manifestations, that a biological inflammatory syndrome is associated in 75% of cases, that no specific autoantibody has been identified, that ocular involvement most often resolves whereas cochleovestibular involvement may be severe and irreversible, that therapeutic management lacks consensus in the absence of a prospective randomised study, that corticosteroid therapy is the first-line treatment and that combination with an anti-TNF should be discussed early 1.

This text rests on a French national study published in 2017 in Autoimmunity Reviews, of which Arsène Mekinian is likewise the last of 24 named authors and the corresponding author 2. The study brings together 40 French patients and 22 cases from the literature, that is 62 patients, of whom 31 women, of median age 37 years with extremes of 2 and 76 years. At diagnosis, 61 of the 62 patients, that is 98%, had audiovestibular symptoms, with bilateral deafness in 41% of them and deafness in 31%; ocular signs were present in 57 patients, that is 92%, including interstitial keratitis in 31 of them, that is 51%. First-line treatment consisted of corticosteroids alone in 43 patients and of corticosteroids combined with an immunosuppressant in 18 patients, with no difference in audiovestibular response between the two, 30% against 22% with a p of 0.8. In all, 61 patients received 126 lines of treatment, including 10 of infliximab. The audiovestibular response was more frequent with infliximab than with conventional disease-modifying treatment or corticosteroids alone, 80% against 39% and 35%, and infliximab was the only significant predictor of audiovestibular improvement, with an odds ratio of 20.7, a 95% confidence interval of 1.65 to 260 and a p of 0.019; the authors conclude that prospective studies remain necessary 2. Three review texts complete this body of work: a review in French published in La Revue de médecine interne in 2021, of which he is 1st of four authors and corresponding author, which sets out the distinction between the typical and the atypical form and the two-year threshold between the two organ manifestations 3; an English-language review published in the European Journal of Internal Medicine in 2025, of which he is 4th and last author, which recalls that there is neither a diagnostic criterion nor a specific biomarker and that the only therapeutic data available come from cases and series 4; and a review published in the Revue du Rhumatisme in 2023, of which he is second and last of the two authors 5.

Bradykinin-mediated angioedema. This body of work runs continuously from 2012 to 2024 and is almost entirely absent from the current version of the page. The French national study of acquired C1 inhibitor deficiency, published in Medicine in 2016, brought together 92 cases, of median age at onset 62 years, with facial oedema and abdominal pain as the most frequent symptoms; 15 patients were admitted to intensive care for laryngeal oedema and one patient died. Anti-C1 inhibitor antibodies were present in 43 patients. The associated diseases were first non-Hodgkin lymphoma in 44 patients, including 24 splenic marginal zone lymphomas, and monoclonal gammopathy of undetermined significance in 24 patients; 3 patients had myeloma, 1 AL amyloidosis, 1 a bronchial adenocarcinoma and 19 no associated disease. Icatibant relieved all 26 patients treated and C1 inhibitor concentrate 19 of the 21 patients treated; 6 patients had a thromboembolic event on tranexamic acid; rituximab prevented attacks in 27 of the 34 patients treated and splenectomy controlled the disease in 7 patients operated on for a splenic marginal zone lymphoma; after a median follow-up of 4.2 years, 52 patients were in remission of their angioedema. Arsène Mekinian is 12th of 14 named authors there 6. The next national cohort, published in 2024 in The Journal of Allergy and Clinical Immunology: In Practice, covers the 41 patients whose acquired deficiency is associated with a monoclonal gammopathy of undetermined significance, over thirty years: 68% had anti-C1 inhibitor antibodies, the monoclonal component was an IgM in 24 patients, an IgG in 11 and an IgA in 6, mean age at first attack was 63 years and at diagnosis 66 years; over a median follow-up of 7 years, 14 patients, that is 33%, progressed to an overt haematological malignancy, including 7 lymphomas and 3 myelomas, which corresponds to an incidence of 4% per patient-year, and 15 patients, that is 35%, were in complete clinical remission of their angioedema at the last visit, 60% of them with a serum monoclonal immunoglobulin that had become undetectable. He is 5th of 35 named authors there 7. Earlier, a series of seven patients treated with rituximab, published in 2012 in the Journal of Clinical Immunology under the collective signature of the reference centre for kinin-mediated angioedema, reported complete clinical efficacy in three patients, partial in two and none in two, with biological normalisation in only two patients; he is 4th of 15 named authors there 8. The rest of this body of work comprises the national study combining hereditary angioedema and lupus, which recorded 6 French patients and 32 cases from the literature, of whom 26 women, with no case of systemic lupus among the six French cases 9; a comparison of attack severity between hereditary angioedema and angioedema induced by angiotensin-converting enzyme inhibitors, in 56 patients and 534 attacks, which shows that involvement of the tongue, the lips and the larynx is significantly more frequent in the drug-induced form, with odds ratios of 8.70, 20.4 and 7.50 10; two French reviews of 2015 on acquired angioedema and on drug-induced angioedema 1112; a description of three cases of hereditary angioedema with a mutation of the F12 gene associated with immune disorders 13; the national study of Gleich syndrome, that is to say episodic angioedema with hypereosinophilia, in 30 patients of median age 41 years, where an abnormal T-cell phenotype was present in 12 patients, that is 40%, and was the only factor associated with a shorter time to the next flare, with a hazard ratio of 4.15 and a confidence interval of 1.18 to 14.66, p equal to 0.02, a work of which he is 2nd of 21 named authors 14; and a 2024 case series on recurrent cervical swelling syndrome 15.

Autoimmune cytopenias. The most structured work concerns immune thrombocytopenia associated with myelodysplastic syndromes and chronic myelomonocytic leukaemia, published in Haematologica in 2021, of which Arsène Mekinian is last of 28 named authors and corresponding author 16. Forty-one patients were included: the thrombocytopenia was chronic in 26 of them, that is 63%, the myelodysplasia was of low risk in 30, that is 73%, and 24 patients, that is 59%, had chronic myelomonocytic leukaemia; an associated autoimmune disease was noted in 10 patients, that is 24%. Compared with patients with primary immune thrombocytopenia, these patients bled more severely at a comparable platelet count; first-line treatment consisted of corticosteroids in 98% and intravenous immunoglobulins in 56%, the immunoglobulins being less often effective than in the primary form; 10% of patients, that is 4, had a multirefractory form, against none in the control group. After a median follow-up of 60 months, overall survival did not differ from that of primary thrombocytopenia, and leukaemia-free survival was better than in patients with myelodysplasia without immune thrombocytopenia 16. On the therapeutic side, a retrospective study of 35 patients treated with vincristine for immune thrombocytopenia, published in 2016, reports an initial response, defined as a platelet count rising above 30 × 10⁹/L, in 86% of patients after a median of seven days, a median duration without failure or relapse of 15 months, but only seven patients with a maintained response at two years and 23% of adverse events, including seven neuropathies; he is 7th of 11 named authors there 17. He is also a co-signatory of a multicentre series of 27 cases of intracranial haemorrhage during adult immune thrombocytopenia 18 and of a multicentre retrospective study of front-line rituximab in autoimmune cytopenias associated with an indolent B-cell clone, published in 2025 in the American Journal of Hematology, whose MEDLINE record, which classes it as a letter, carries no abstract and therefore no figures; he is 45th of 50 named authors there 19. A case of refractory Evans syndrome treated with plasma exchange, of which he is last of five authors, completes this set without constituting proof 20.

Systemic lupus. The most substantial work is recent and joins the haematological ground of the department. Published in January 2026 in JAMA Dermatology, a national multicentre retrospective case-control study, conducted on data from January 1975 to January 2023 under the collective signatures of the EMSED and MINHEMON groups, describes lupus-like manifestations during myelodysplastic syndromes and chronic myelomonocytic leukaemia: 24 patients, of whom 9 women and 15 men, of median age 65 years, 19 systemic lupus and 5 cutaneous lupus, median follow-up 4.5 years; skin involvement was the most frequent manifestation, in 17 patients, that is 71%, and chilblain lupus was its predominant subtype, in 6 patients, that is 35%. Compared with patients with idiopathic systemic lupus, these patients were older, 65 years against 23, more often men, had less renal involvement, 2 cases that is 10% against 27 that is 71%, less joint involvement and fewer anti-double-stranded DNA antibodies, all significant differences. Central histological review reclassified six skin biopsies, that is half of the biopsies reviewed, as cutaneous localisation of the haematological disease, and identical myeloid variants were found in blood and in skin in six of eight patients, which argues for a clonal inflammatory process rather than for classical autoimmunity; lupus treatments were often of little effect whereas treatments directed against the clone, azacitidine or allogeneic transplantation, brought about a parallel haematological and lupus response in five of seven patients. Arsène Mekinian is 24th of 25 named authors of this work 21. His two other signatures in lupus are co-signatures and must be read as such: he is 24th of 49 named authors of a collective exome sequencing work published in 2026 in EBioMedicine, which covered 263 people from 172 families and established a molecular diagnosis in 17 patients from unrelated families, that is 10%, with a yield approaching 33% in syndromic and very early onset forms 22; and 44th of 63 expert signatories of international and multidisciplinary recommendations on the use of biologics in systemic lupus, published in 2017 23. In Sjögren's syndrome, he is 11th of 39 named authors of the ETAP trial, a multicentre double-blind placebo-controlled randomised trial conducted in 17 centres from 24 July 2013 to 16 July 2018: 110 patients were randomised, 55 on tocilizumab and 55 on placebo, and the primary endpoint at week 24 was met in 52.7% of patients on tocilizumab against 63.6% on placebo, a difference of minus 11.4%, the trial concluding that tocilizumab had no effect on systemic involvement or symptoms 24. He is finally 10th of 22 named authors of a deep immunophenotyping work conducted in 206 patients, which identifies two cell populations associated with the occurrence of lymphoma during Sjögren's disease, with a sensitivity of 78.9% and a specificity of 76.8% for their combination 25.

Myositis. Contrary to what the preparatory inventory suggested, he signs in this field a work in a senior author position. Published in March 2025 in RMD Open, a retrospective observational study of patients with inflammatory myositis followed at Saint-Antoine Hospital between 1997 and 2020 included 78 patients, of median age 49 years, 67% of them women: 33 had dermatomyositis, 18 an antisynthetase syndrome, 12 an overlap myositis, 11 an immune-mediated necrotising myopathy and 4 an inclusion body myositis. Cardiac involvement was present at diagnosis in 12 patients, that is 15%, and 15 patients, that is 19%, had a cardiovascular event during follow-up. Patients with cardiac involvement at diagnosis more often had a cardiovascular event, 6 of 12 against 9 of 66, with a p of 0.01, and they had it earlier, median time of 9 months against 84 months, with a p below 0.01. Arsène Mekinian is last of six named authors and corresponding author of this work 26. He is moreover a co-signatory of three collective works on myositis: a multicentre retrospective cohort of 73 patients with cancer-associated dermatomyositis, published in 2025, where he is 10th of 26 named authors 27; the study of 121 cases of anti-MDA5 antibody dermatomyositis published in Neurology in 2020, which isolates three subgroups of differing prognosis among the 83 patients analysed, where he is 29th of 43 named authors 28; and a case-control study nested in a cohort of 234 anti-MDA5 antibody patients, published in 2026, which compares 27 patients treated with the combination of a JAK inhibitor and a calcineurin inhibitor with 52 matched controls and finds no survival benefit, with a hazard ratio of 1.02 and a confidence interval of 0.48 to 2.16, where he is 19th of 48 named authors 29. A case of severe necrotising myositis under the combination of nivolumab and ipilimumab, of which he is last of six authors, completes this list 30.

Where care is organised

These diseases are followed in the department of internal medicine of Saint-Antoine Hospital, AP-HP, Sorbonne Université, attached to the medical and university department devoted to inflammation, immunopathology and biotherapies, designated DHU i2B until about 2019, then DMU 3iD and DMU i3 in the affiliations of his publications. The French national protocol for Cogan's syndrome was drawn up under the aegis of the reference centre for autoinflammatory diseases and inflammatory amyloidosis, CeRéMAIA, and of the rare autoimmune and autoinflammatory disease network, FAI²R [A][B]. The department's publications on angioedema carry, in the address declared by the authors, the mention of the reference centre for kinin-mediated angioedema, CREAK 1112, and the 2012 series on rituximab is signed collectively in the name of that centre 8. The works that cross autoimmune disease and myeloid haematological malignancy are signed in the name of the MINHEMON network 21, the network to which the page devoted to myeloid haematological disorders and inflammation refers.

Care is by construction multidisciplinary. In Cogan's syndrome, it brings together the ophthalmologist for corneal involvement, the ear, nose and throat specialist for cochleovestibular involvement and the internist for general and vascular involvement; the authors of the national protocol come precisely from these three disciplines. In bradykinin-mediated angioedema, it brings together laboratory immunology, which measures the C1 inhibitor and looks for autoantibodies, and haematology, because of the frequency of the associated monoclonal gammopathies and indolent lymphomas 67. In autoimmune cytopenias associated with myelodysplasia and in the lupus manifestations of these same haematological diseases, it brings together internal medicine, clinical and laboratory haematology and, for the cutaneous forms, dermatology and histopathology 1621. Complex decisions belong to the multidisciplinary team meeting and intravenous treatments to the day hospital.

What is not known

On Cogan's syndrome, the state of knowledge is explicitly incomplete, and it is his own texts that say so. There is neither a validated diagnostic criterion nor a specific biomarker, no autoantibody is specific to the disease, and the diagnosis remains one of exclusion 14. No prospective randomised study has been conducted, which deprives the national protocol of an experimental foundation: its therapeutic proposals rest on retrospective series and on published cases 14. The most cited result of this body of work, the superiority of infliximab for the audiovestibular response, comes from a retrospective study that pools 40 French patients and 22 cases from the literature, with only 10 lines of infliximab; its confidence interval, from 1.65 to 260, is very wide, and the authors themselves conclude that prospective studies are necessary 2. This result therefore does not say what should be done for a given patient, and it promises no recovery of hearing. It must be added that the national protocol, although published on the website of the Haute Autorité de santé, has not been validated by it, as the Haute Autorité de santé itself states on the page of the document [B].

On bradykinin-mediated angioedema, all the studies cited are retrospective and none is comparative. The cohort of 92 patients of 2016 and that of 41 patients of 2024 describe associations and courses, they do not demonstrate the effect of a treatment 67. The series of seven patients treated with rituximab in 2012 concludes moreover that efficacy is inconsistent 8. The question of when to treat the underlying haematological disease in order to control the angioedema, and which one to treat, remains open, as does the optimal interval of the haematological surveillance work-up, which the 2024 authors propose to be annual without that interval having been compared with another 7.

On autoimmune cytopenias, the study of 41 patients combining immune thrombocytopenia and myelodysplasia is retrospective and its sample size is small for a subject with so many subgroups; the most surprising result, better leukaemia-free survival in patients with immune thrombocytopenia, has not been independently replicated and its mechanism is not established 16. The vincristine study covers 35 patients without a comparison arm, and its own reading is cautious since only seven patients retained a response at two years 17. The 2025 study of front-line rituximab in cytopenias associated with an indolent B-cell clone is published as a letter and its MEDLINE record carries no abstract: no figure from it can be cited here 19.

On lupus, Sjögren's syndrome and myositis, his position is most often that of a co-signatory within collective works, and the page does not present these studies as his own. The 2026 study of lupus manifestations of myelodysplastic syndromes, where his position is close to that of a senior author, covers 24 patients recruited over nearly fifty years, which permits a description but not an estimate of frequency; the comparison with idiopathic lupus is made with much younger controls, which weighs on the interpretation of the differences observed 21. In Sjögren's syndrome, the ETAP trial is one of the few randomised trials in this field and it is negative: tocilizumab did no better than placebo, and the response rate observed under placebo, 63.6%, is a reminder of the difficulty of assessing a treatment in this disease 24. The cell markers predictive of lymphoma described in 2025 are the results of a single series and have not been validated prospectively or independently 25. In myositis, the cardiological cohort of 78 patients is single-centre, retrospective and spread over 23 years, a period during which the means of cardiac investigation changed, which precludes drawing from it a general incidence rate 26; the 2026 study of the combination of a JAK inhibitor and a calcineurin inhibitor shows no survival benefit and its authors stress that it included the most severe forms 29.

Finally, two framing points. The first concerns the rarity of these diseases. For Cogan's syndrome, the Orphanet entry, which is not his, gives a prevalence of 1 to 9 cases per million inhabitants while indicating that the real prevalence is unknown and that about 300 cases have been reported to date, with a median age at onset between 20 and 30 years; this entry carries as the date of last update of its summary the month of August 2019, that is five years before the national protocol to which it refers [C]. The second point concerns the treatments cited: none of the molecules named on this page has a marketing authorisation in Cogan's syndrome, and their use there is a case-by-case decision within the framework of the national protocol.

References

Published work he has taken part in, on this subject.

General information only. This page does not replace individual medical advice. Updated: 10 September 2026.