Efficacy of Pre-exposure Treatment With Hydroxy-Chloroquine on the Risk and Severity of COVID-19 Infection

There is a pandemic in the world by COVID-19. Currently, the pharmacological curative or prophylactic treatments for this infection are not known. Recent studies have suggested that Hydroxy-Chloroquine could be effective in vitro and in vivo against COVID-19. The main objective of this study is to assess in patients with autoimmune disease treated with long course Hydroxy-Chloroquine initiated before the pandemic COVID-19 had an independent protective effect on the risk or the severity of infection with COVID-19.

A pre- or post-exposure treatment strategy has been validated in some infectious diseases. In particular, in HIV infection, this type of prophylactic treatment reduces the rate of infection in at-risk populations. The first studies from Chinese show that in case of immunosuppression or immunosuppressive treatment, whatever the causal pathology, COVID-19 infection is more severe. The present study presents a population of patients with lupus (SLE) or Gougerot's disease (SGD) who are treated for a long time, with Hydroxy-Chloroquine. The protective effect against COVID-19 infection of Hydroxy-Chloroquine compared to populations not exposed to this drug requires to be assessed in patients and their control groups under or without immunosuppressive treatments.

It is hypothesized that long-term treatment with Hydroxy-Chloroquine in SLE or SGD taken in its usual indication before the onset of the pandemic could decrease the number of COVID19 infections and/or the intensity of the disease.

Eligibility Criteria:
Inclusion Criteria:

Group with hydroxychloroquine treatment (HC +):

* LED/SG diagnosed
* Treatment with Hydroxy-Chloroquine in the 3 months before and during the outbreak at COVID 19, at least in December 2019. Patients may have treatment with immunosuppressants in combination with Hydroxy-Chloroquine.
* COVID19 diagnostic questionnaire and available serology result.

Group without hydroxychloroquine treatment (HC-) :

* No Hydroxy-Chloroquine intake for more than 12 months

  --\> HC- without an immunosuppressant
* Viral hepatitis C cured for more than 12 months or primitive bile cholangitis (CBP) whose diagnosis is based on international criteria.
* Non-significant liver fibrosis assessed either by historical histology or by fibroscan with non-significant liver fibrosis Metavir - F3 (at last available examination)
* No Hydroxy-Chloroquine, or immunosuppressants have been taken for more than 12 months.
* COVID19 diagnostic questionnaire and COVID19 serology result available.

  --\>HC- with an immunosuppressant
* Diagnosis of LED/SG according to the CAB criteria revised in 1997 or autoimmune hepatitis according to the international criteria validated in 2008.
* Patients treated with immunosuppressants for at least three months before the start of the pandemic at COVID 19, at least since December 2019.
* COVID19 diagnostic questionnaire and available serology result.

Exclusion Criteria:

* Anti-CD20 or Cyclophosphamide taken during the six months prior to the completion of the COVID 19 serology.
* Refusal of a blood test for antibodies to COVID-19.
* Protected adults
* Pregnant or breastfeeding women.
* Lack of health insurance coverage